#35 - Nir Barzilai, M.D.: How to tame aging
Episode Stats
Length
2 hours and 48 minutes
Words per Minute
160.93721
Summary
Nir Barzilai is the founding director of the Institute for Aging Research, the Nathan Schock Center of Excellence in Basic Biology at Albert Einstein, and the Director of the Longevity Genes Project at Cornell University. He is also leading the effort to test metformin in a prospective clinical trial for non-diabetics with respect to aging.
Transcript
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Hey, everyone. Welcome to the Peter Atiyah Drive. I'm your host, Peter Atiyah.
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The drive is a result of my hunger for optimizing performance, health, longevity, critical thinking,
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along with a few other obsessions along the way. I've spent the last several years working with
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some of the most successful top performing individuals in the world. And this podcast
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is my attempt to synthesize what I've learned along the way to help you live a higher quality,
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more fulfilling life. If you enjoy this podcast, you can find more information on today's episode
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Hey, everybody. Welcome to this week's episode of The Drive and Happy New Year to everyone. We took a
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week off, as you probably noticed. So hopefully everybody's ready to jump back into this fun
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stuff. My guest this week is Nir Barzilai. And if you're at all into the space of longevity,
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he'll be no stranger to you. Nir is the founding director of the Institute for Aging Research,
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the Nathan Schock Center of Excellence in Basic Biology at Albert Einstein. He's completed two
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fellowships, one in metabolism at Yale, the other in endocrinology and molecular biology at Cornell.
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He directs the Longevity Genes Project. And in my estimate, Nir is probably the most knowledgeable
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person ever on the genetics of longevity. And we talk a ton about that during this episode.
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He also is leading the effort to test metformin in a prospective clinical trial for non-diabetics
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with respect to aging. And this is referred to as the TAME trial. We get into that obviously in detail
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here and also will use a lot of the data for that in the show notes. This is in many ways,
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I think Nir is probably one of the most insightful people when it comes to understanding the clinical
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benefits of metformin. And we talk about that a ton. We also talk about insulin resistance. I can't
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resist the urge, no pun intended, I guess, to get into sort of a detailed discussion on what IR
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is with sort of people who are really deep in this space. We talk a lot about IGF and growth hormone.
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And I got to tell you, this is a topic that you've probably heard me waffle on a little bit
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because I'm still really kind of on the fence about this relationship of IGF, GH. I think the
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centenarian data point in one direction. I think the epidemiology outside of centenarians point in a
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different direction. And of course, none of this really speaks to the question I get asked constantly,
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which is, do you think administration of growth hormone is beneficial from a lifespan or health
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span perspective, or do you think it's harmful? And truthfully, I've always leaned towards the harmful
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side, but we get into this in detail and near offers some great insights. Certainly for me,
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I was, I was really helped by this process. We do go back and talk about the centenarians.
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And because I'm in the midst, as some of you know, of writing this book, I'm knee deep on all that
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literature. And so it was really great to kind of clarify a few things that I think even if you're
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not steeped in this stuff, what you'll find very interesting. And of course we talk about all of my
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other favorite topics like autophagy, caloric restriction. We even get into a little bit of the stuff
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around NAD and nicotinamide riboside and things like that. So overall, I think this is a bit of a
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technical episode, but not that technical. We've certainly done more technical stuff. The show
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notes will be valuable as always, especially for a show of this nature. So with nothing else to add,
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I'm good. I can't believe not only did you make it down here on time, but you made it down here
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Yeah, this is, I don't know. These days, this weather is so unpleasant, but yeah, you beat
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It's unpleasant for you because you're in California most of the time.
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Yeah, yeah. I think that's part of it. But you're from Israel, so this has to be unpleasant
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Got it. Well, speaking of which, so you were born in Israel. You spent how long there?
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Yes, I served military time. I was a nurse and a medical student. I went to the Technion Medical
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School. I went then to Hadassah Hospital for residency, which I finished. And only then I came
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to the United States. I was at Yale with Ralph DeFronzo doing metabolism. Actually, I was looking
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at the mechanism of action of metformin in 1987 before it was approved for use in the United
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States. There's a serendipitous connection to that later. And then I went to Cornell for an
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endocrine fellowship, and then I was recruited to Einstein. And so my first part of my life was
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metabolism. But then I started doing what I really was interested in, and this is aging and the
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And I remember reading a quote once from you that said, maybe paraphrasing, but metformin is the
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Well, in a way it was, but this is life in retrospect, right? I wasn't really expecting. I was done with
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metformin in 1988. I was done with metformin until it started again about three, four years ago.
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Well, I can't wait to talk about metformin because they're probably, I'm trying to think,
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if I think of four or five exogenous molecules, which is just the terminology I use to describe
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anything that you ingest or take that comes from outside the body. So I would include drugs,
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supplements, hormones, anything in there. But when you lump all of these things together,
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if I were to say, what are the three or four of these that I am asked about the most frequently
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from patients or frankly, anybody, if I'm at a party and I let it slide, what I do for a living,
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the first question is, should I be taking metformin? And there's usually a handful of
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others that they want to know about. Should I be taking nicotinamide riboside? Although they
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usually don't say that. They usually say, should I be taking NAD or something to that effect? So
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it's wonderful that we will be able to speak today because few people can speak about metformin
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the way you can. And so I'm really looking forward to that. But before we go down that path,
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I do still want to kind of understand a little bit more about your journey and your interest
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in endocrinology. Did you know from day one when you entered the field of medicine that this was
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the area that you wanted to study? Yes. I was interested in aging from the time I was pretty
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much 13 and spent weekends with my grandfather who was telling me his life story. And his life story
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wasn't easy. And he did lots of physical things and he dried the swamp and he did this and that.
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And I'm looking at the man who was then 68 years old that walks slowly, he's obese, white hair,
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and he just didn't look like somebody who did everything he told me to do. And you know,
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they say that children have imagination, but most kids don't see their grandparents as what they will
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be, right? They see them as, I don't know how they got there. And this really stuck with me. And I
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started to be interested in the biology of aging. When I was, for example, when I did my residency,
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I always was interested in how, not what's the age of the patient, but does he look older
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or younger than his age? I kind of realized intuitively that there's a chronological age
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and a biological age. And what is this differences between the biological and chronological age?
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And of course, as a physician, it looked like endocrine is a good place to start because you knew that
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there's a lot of endocrinology in aging and you assumed that hormones are going down or some are
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going up. But if you could fix that, maybe you could fix a lot of aging. Now, everything that
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happened in my life was fascinating from the biology of aging. Replacing the hormones wasn't really a part
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of it, but we'll get to it. Going back to the hormone thread, the most obvious example of changes
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in hormones with aging, of course, occur in women where, you know, they have this very abrupt
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change in one of their endocrine systems, this androgen system. Did you think about it even
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more broadly than that? For example, like what was happening in thyroid hormone and what was
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happening in fuel partitioning hormones and other things like that? Oh, absolutely. Absolutely. But
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I'll tell you to the point when there was a discussion whether to do the Women Health Initiative.
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You know, many people thought this is a waste of time. You know, we know that estrogen is good for
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women. There's lots of studies like that. Of course, it's major in aging. And I didn't look at
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this simply for maybe two reasons. One is men are also aging and in several ways similar to women.
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And that's not an estrogen story. And it wasn't, the testosterone decrease wasn't really as dramatic
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as the estrogen decrease. So I didn't, I thought that there's a lot of aging that's done without
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estrogen. Let's start with that. And also you're replacing just one hormone with lots of hormones
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are changing. It didn't look like a good study to me. Well, and especially at the time, and I try to
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temper my criticism for that study by trying to have some empathy for the fact that the investigators were
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dealing with what the treatment protocols were at the time, but to use oral estrogen that's,
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you know, conjugated equine to use synthetic progestin and not even actual progesterone.
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And there, you could come up with a list of 18 things that in retrospect are so obvious why that
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study was a failure. Absolutely true. But the other part of that is that the way to show effect of
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estrogen in animal models was to take their ovaries out and give them estrogen. And then you could show,
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you could do lots of provocation. It was good. So estrogen is a good hormone on a young body,
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but then there were studies that were hardly published, but I was aware of them of taking
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old animal, you know, so you could take the young animals in just one center in Houston. They did it.
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You took the young animal, you took their ovaries out, you gave them estrogen and you employed a stroke
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model. Okay. And when you gave estrogen, the stroke was smaller and everything. When you did the same
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in older animals, the stroke became worse. Okay. And they couldn't publish it for a while because
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they said, well, it's old animals. So they have other diseases or other things, but every experiment
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that had estrogen in old model wasn't, was the opposite. Not only that it didn't affect, it was the
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opposite, which what happened, you know, to the WHI in a certain ways. Yeah. Although I still think
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that the, it was probably the breast cancer that garnered the most headline in the WHI. And actually
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that's an interesting topic, which I'll be going into in great depth on another episode. There's a
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great book that just came out that tackles this, that goes through the history of the WHI. At what
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point, well, let's go back to the Metformin thing actually. So it's 1987 and you're thinking like,
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okay, Metformin is the next line of agent we will use to treat type 2 diabetes.
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So Metformin was already in clinical practice in Europe. Is that correct?
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So Metformin a few years ago was 60 years. So we're talking about, you know, 1950 or something,
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1950, 1960. When I was in Israel, I prescribed Metformin. You know, that was the first line
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for type 2 diabetes. What took so long for it to come to the U.S.?
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That's a terrible story that still continues. You know, the FDA said, we don't know. We don't
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know that Metformin is going to be effective in the population in the United States. So you have to do
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the studies. And it was Bristol-Myers really that got to do the studies. And basically they had to do a
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phase 3 study again to show that Metformin is effective as sulfonylurea as an indication for
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type 2 diabetes. And if even then, the idea was that it will be good only in obese people,
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which happened not to matter much because all the type 2 diabetes in the United States were obese,
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but it was really a matter of regulation. And part of having regulation was that the FDA asked more
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studies to understand the mechanism of aging and Metformin. And in a certain way, maybe they are
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right because Metformin mechanism of action is really complicated. And I'm not sure that today
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as a new drug, it would be approved. Interesting. Where do you think it would fail? In safety or
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efficacy? No, it's not in mechanism. In the inability to elucidate the mechanism.
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Right. When you come to the FDA and you say, you know, we've done that and we've done this in animal
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and we've done this in cells, and you're trying to show what is the major mechanism of action,
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you would have failed. So what I showed in humans is that Metformin targets hepatic glucose production
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or the insulin sensitivity of the liver. And that's the major mechanism of action. Unlike,
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for example, sulfonylurea that increased insulin secretion, right? Or TZDs that increase the insulin
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sensitivity in the muscle more than in the liver. So this was a mechanism that you could pack
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to the FDA, but it's really not the intracellular mechanism of Metformin.
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So at the time, was it understood what Metformin's activity was on complex one of the mitochondria?
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No, not really. This came later. I don't know what year, but it came later. It came when the
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seahorse's assays were developed to show really which mitochondria in which pathway of mitochondria.
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mitochondria, you have changes. Maybe for the listener, explain what a seahorse assay is.
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Seahorse assay is an assay to look at mitochondrial action, whether you extract mitochondria or even
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tissues. It really shows some relationship between oxygen consumption in relationship to polarity.
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And it's very sensitive to look at some of the effects of drugs that are interfering with
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mitochondria action or decreased mitochondrial activity.
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It's almost like the indirect calorimetry of the mitochondria.
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Right, right. Indirect because it's a provocative test, really. So yes.
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Metformin was discovered from a plant as well, correct?
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And it was a French lily, obviously. And this was discovered in the 40s or 50s?
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Correct. The first thing that happened, there was a drug by the name of metformin,
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It's much more potent because unlike metformin, it doesn't need a transporter to get into the cells.
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On the other hand, it was associated with a lot of lactic acidosis.
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And then metformin was a safer part with much less of a lactic acidosis side effects.
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What is the mechanism by which metformin caused lactic acidosis?
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Because in all the use I've seen of metformin clinically, I've never seen a case of it.
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Which is not to say it doesn't happen. I'm sure it does. And you could stack risks by taking someone
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with renal insufficiency, giving them contrast and tons of metformin. But in medical school,
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this was like the board question you got asked every single test. What do you have to worry about
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with lactic acidosis? What's the putative mechanism by which that happens?
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So, first of all, I would tell you that in my study in the 80s, every patient that we gave
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Within the normal range. So, if it's two was the...
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The cutoff. So, it was, you know, between... went from 1.5 towards the two. And sometimes
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even went over the two. But it wasn't really anything associated with acidosis.
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No. No. No onion gap. Not anything like that. And it probably has to do... I don't know that
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I can tell you for sure, but it has to do with what happens when complex one, part of the metabolic
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effect when complex one is inhibited. But there's lots of speculation and I don't really care to
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comment on that. But I think what became clear, there is a whole... we call it endocrinologists,
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call it MALA. It's metformin-associated lactic acidosis. In other words, we moved away
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from metformin-causing lactic acidosis to the association because it's, if anywhere, it described
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more in people that have kidney failures or have heart attacks or something and had lactic acidosis
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and were on metformin too. And that was kind of the association. But it's not clear to me that
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there are truly people who develop lactic acidosis from metformin that is just because of metformin
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and not associated with something else. I'm glad to hear you say that. That's sort of generally
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been my bias, but I'm happy to be corrected if that bias is incorrect. But yeah, I've always
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thought that, frankly, so many of the drugs that we're really interested in now as we look back
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from an aging perspective, whether it be metformin or rapamycin, so many of the negative side effects
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that people typically associate with those drugs are very difficult to isolate from the patients
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in whom those drugs have historically been given. And so it's nice to hear that Mala is now being
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generally recognized as an alternative viewpoint to that. You know, metformin is to me an interesting
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drug from a diabetic standpoint because, and I don't know that this was appreciated in the 80s,
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in fact, I would suspect it was not, because there's really two macro strategies for improving type 2
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diabetes. You can, obviously the highest goal is to control glucose levels, so to regulate the degree
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of glucose in the blood. But you can do that through, at the highest level, two ways. You could
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increase insulin, either exogenously or through increased insulin production pharmacologically,
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or you could reduce glucose. And of course, metformin falls into the latter category of that,
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or increasing muscle insulin sensitivity to enhance glucose disposal. Today, it's generally regarded that
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while both strategies will have an equal benefit on the microvasculature, the glucose lowering by insulin
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lowering, so the less glucose production strategy, has a superior effect on the macrovasculature. And therefore,
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metformin would be a better alternative to, for example, a drug that's going to increase insulin production
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out of the pancreas. Was it appreciated at the time, meaning when you were doing this in the late
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80s, how potentially beneficial this drug was? Well, at that time in the United States, it was all about
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insulin resistance. You know, people like Jerry Riven, Ralph DeFronzo, the people at the NIH, Ron Kahn,
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were all, you know, discovering the insulin receptor, discovering insulin resistance,
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discovering the association of insulin resistance with the metabolic syndrome.
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So it was all, we all had the bias that the major problem with type 2 diabetes is insulin
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resistance. And, you know, we know now that it's a total collaboration. Yeah, you increase
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insulin resistance and the pancreas have to secrete more insulin. And we humans, at least in the condition
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of our environment, obesity, everything, many of us, I would say 40%, cannot deal with it. And we become
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diabetic. There is this starling curve of the pancreas, you know, like for the heart, that you
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increase insulin secretion. And at some point, you cannot increase insulin secretion, you become
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diabetic and then insulin secretion decrease. And so insulin resistance was a major way. And that's why
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metformin was a good place to come with, you know, at least it affects mainly the hepatic glucose
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production rather than the muscle. Although I have to tell you in vitro on muscle specimen,
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Let's talk about this idea of insulin resistance. I think there are a few terms that leave me scratching
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my head more than that one. So this is an example of something where maybe five years ago, I thought
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I really knew what insulin resistance was. And I think today I'm pretty sure I don't know what it is
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in the sense that when you take the typical phenotype of someone who's insulin resistant,
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what do they look like biochemically and anthropomorphologically, right? So they're
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hyperinsulinemic, they have elevated levels of glucose, they probably have some degree of obesity or
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adiposity. So what does that mean? Because clearly their fat cell is quite sensitive to insulin.
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If the fat cell ever became resistant to insulin, you could not re-esterify fatty acids and you would
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have an endless stream of lipolysis exiting fatty acids from the fat cell. So you'd actually be quite
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lean. There's something going on in the muscle that clearly is resistant to the effect of insulin. But
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of course there are both insulin dependent and insulin independent means by which we can dispose
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of glucose. And this is where, coming back to what you said a moment ago, I actually wanted to ask
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you that question, which is, but we'll park it, but the question was, does metformin participate in
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the AMPK driven insulin independent modality of glucose disposal? You're nodding, so I think that's a yes
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and we'll come back to it. And then there's the liver. And this is the one to me that is the most
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complicated and the one I'd like to begin with. So before I ask you to elaborate on the specifically what is
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meant by insulin resistance in the liver, am I a complete moron for not understanding this?
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No, but can I make it a little bit more interesting even? Because I need to bring it to aging.
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I would love to talk about diabetes, but let me just put up front. I'm not sure that the diabetes
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property of metformin are really the aging properties of metformin. Okay. This is my provocation.
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But let me go back to insulin resistance because in 1997, a science paper appeared that made it
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the best day of my life and the worst day of my life. Okay. Wow.
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What was the paper? The paper was taking a nematode. Okay. So a primitive model decreasing
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the insulin sensitivity. This is known as the DAF2 model. And when you do that, the nematode accumulates
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fat in their intestinal cells. So they are becoming visceral obese and they live several times longer.
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So why is it the best day in my life? Because you could, with one genetic manipulation,
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extends lifespan significantly. That meant going from hope, actually from nothing.
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No, that's Gary Rufkin. But at the same time, Cynthia had their DAF16. Tom Johnson has had the
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age one model. There are several papers that came and all of them said, hey, we can change
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a lifespan. And the example was always insulin sensitivity.
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And this mutation, to be clear, because between DAF2, DAF16 and the dietary manipulations,
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there are several permutations of that C. elegans model. But just to make sure I know which paper
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we're talking about, this was only attenuation of DAF2, nothing to DAF16 and nothing to dietary
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Can you just, for the listener, define what is the analog of DAF2, DAF16 in us?
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DAF2 is the insulin receptor. And DAF16 is the FOXO, the FOXO transcription factor. But the point
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is, at that time... Yeah, you took a worm that normally lives two weeks and you turned down its
00:25:23.180
Right, right. But you made it insulin resistant and it was accumulating fat. And what was I bringing
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in to the field? I was saying the major reason for aging is this insulin resistance syndrome. And the
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main part of the insulin resistance is accumulation of visceral fat. And so the premise was good. The
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example was disaster to me. I had the JCI paper at that time in press, really showing with MRI pictures,
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how caloric restriction decreases the visceral fat. I was talking about the biology of those fat and stuff.
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And it was a major paradox for us in the field and how we continue if we're saying insulin resistance is
00:26:12.320
good for longevity and everybody in diabetes knew that this is a disaster. Why am I telling you that? Because
00:26:19.780
I learned later, I was thinking later on experiments that I've done. Oh, so first of all, the experiment
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that I've done that was very conclusive was I took a bunch of rats, 150 actually, and all of them
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underwent surgery after puberty. In some of them, I removed their visceral fat depots by surgery.
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And in the other, it was a sham procedure. So I just moved it, but didn't remove it. And we had three groups
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in the experiment. One was ad libidum feeding. The second was caloric restriction. This is the control.
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They would live 40% better. And the third group was ad libidum feeding of the rats that their visceral fat was
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removed. And I said, you know, without the visceral fat, even with nutrients, they live longer. And
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they actually lived significantly longer than the ad libidum by 20%, but not as much as the caloric
00:27:18.000
restriction. So just to make sure I understand, you had a two to one ratio of your animals because you
00:27:23.580
had... No, I had three groups. Three groups, but one of them was all ad lib feeding of the visceral fat
00:27:29.860
removed. That was... Right. And then of the ones that had sham surgery,
00:27:34.100
they were randomized to ad lib versus CR. Correct. It really showed that visceral fat,
00:27:39.000
the removal of visceral fat had major effect. And when the animals who had the visceral fat removed
00:27:44.980
were autopsied or whatever the word is for rat autopsies, had they figured out a way to reaccumulate
00:27:52.200
visceral fat or where had they accumulated fat? No. In fact, when you do this procedure after puberty,
00:27:58.500
if you do it before puberty, they accumulate visceral fat. Otherwise they don't accumulate much
00:28:03.800
visceral fat. Did they have changes in subcutaneous fat? That's a good question.
00:28:08.420
Mice have it when you do it and rats do not. What did they ultimately succumb to? They all die
00:28:13.800
from the same thing only at different times. Which is what? Cancer? Yeah. It was sprague
00:28:19.060
dolly. So kidney disease and cancers were the leading cause of death. So you basically got half the
00:28:24.880
benefit of CR by doing this operation. By eating ad libidum, but without visceral fat. Yeah.
00:28:32.000
So you understand it's very... Sorry, one other question, Nir. Was there any change in their
00:28:36.440
health span or their spryness? Yes, there was a health span. In fact, what happened to the ad libidum,
00:28:43.160
the ad libidum starts losing weight at the end of their life. And the ad libidum with visceral fat have
00:28:51.280
still gained weight after the others, you know, it was a significant change in weight. And then there's
00:28:57.240
a whole health span, their insulin levels and other things that we've done in parallel. So they were
00:29:02.380
healthy and they were healthier for longer, which is kind of the experiments that we do
00:29:07.220
with animal models. Is it possible to take one of those rats and either through caloric restriction or
00:29:14.860
other dietary restriction, get it to puberty to the point at where you did the surgery,
00:29:19.820
but without any visceral fat. And then ask the question, if they've gone through that period of
00:29:25.360
development without developing visceral fat, do they have somehow protection from the diseases that
00:29:31.360
come even if you feed them ad libidum thereafter? So we did this experiment in Zucker fat animal,
00:29:37.940
Zucker diabetes animal, and we took their visceral fat... Tell people what the Zucker rat looks like.
00:29:44.640
So the Zucker rats are rats that are really, really, really obese, hungry all the time.
00:29:51.980
So they have hyperphagia. They can't stop eating.
00:29:54.160
Right. Because they don't have the leptin receptor. So they are hungry all the time. And they're nasty
00:30:00.700
because you try to come close to them, they think your finger is food. So they're eating all the time.
00:30:06.780
And we did surgery on them before puberty because they became obese really much before puberty.
00:30:12.460
And what happened is by six months, they all become diabetics. Our animals up to four months
00:30:21.220
did not become diabetic. And then between four and six, they became diabetic, although we took
00:30:28.260
their visceral fat. But what we found out that 80% of the visceral fat grew back. So we actually had
00:30:35.780
the perfect experiment. As long as they didn't have visceral fat, they didn't develop diabetes.
00:30:40.280
Once they got the visceral fat, they developed diabetes. But I want to make...
00:30:44.560
And sorry, one other thing. If you took that group and who already developed diabetes with
00:30:49.880
visceral fat, and you just removed the visceral fat, can you reverse the diabetes?
00:30:54.500
No, we've never done this experiment. Don't know. Because we're interested in aging.
00:31:00.700
But I'm telling you all that to make one point, because so far, the paradox just got worse,
00:31:07.220
right? The nematodes with insulin-resistant visceral fat lives longer. And we showed that
00:31:12.280
mammalians live longer if you take this visceral fat and make them insulin-sensitive. Whenever we
00:31:17.720
take visceral fat, we make them more insulin-sensitive, okay? Until I realized one thing. It takes me
00:31:24.600
few hours to make rats insulin-resistant. I give them glucose. I give them free fatty acid. I give
00:31:32.260
them some other things. I can make them insulin-resistant very rapidly. So at first, I used
00:31:38.900
it as, you see, we can do the chronic insulin-resistant in a few hours, okay? You just load
00:31:44.920
them with nutrients, you become insulin-resistant. But then I thought of the aging part. When you get
00:31:51.040
glucose to the muscle, the glucose goes into the muscle, if you're not moving the muscle, it's not
00:31:57.180
going to turn more glucose to energy. It will switch from free fatty acid to glucose, but there's no
00:32:04.020
more glucose burning. So it goes to glycogen, right? And it goes to glycogen, but you keep on putting
00:32:11.360
glucose in the muscle, and there's just so much glycogen that the muscle can store. So the muscle has to
00:32:18.360
become insulin-resistant. Okay? It's a protective mechanism.
00:32:22.480
There's no evidence that the muscle can, in any way, shape, or form, undergo de novo lipogenesis
00:32:33.900
Is there any evidence that muscle can carry out de novo lipogenesis?
00:32:37.500
I don't think so. I don't think so. I'll have to think, because I have a different...
00:32:43.560
I'll have to think about it. But the point is... Okay, but I understand your point. I don't think...
00:32:49.940
If anything, there's no much. The glucose, the muscle tells the glucose, you go somewhere else.
00:32:57.000
So the only organ that can take in a completely excess amount of glucose in the end has to be the liver,
00:33:01.580
because it at least has the capacity to turn excess glucose into fat, whereas all of the other organs
00:33:08.860
That's true. And that's part of, I think, where the glucose is going, okay? To fat and to liver.
00:33:14.320
Okay, so what am I telling you? I'm saying that insulin resistance is a protective mechanism.
00:33:19.980
It's a modulator. It's a stress response. It's something.
00:33:23.420
So now I understand why a stress response mechanism in one animal caused them to live longer,
00:33:31.780
and in another animal, it's a pain in the butt.
00:33:37.100
So I went and I wrote this review with Luigi Ferrucci. I wrote this review where we took
00:33:42.580
all the animals that had problems with their insulin sensitivity, the animals that are insulin
00:33:49.660
resistance and live longer, and the animals with insulin sensitivity that live shorter.
00:33:58.340
And there's a huge list of it. Rapamycin is an example, right? Rapamycin causes insulin
00:34:03.120
resistance, and the animals is the best intervention in rodents. There's a PTB1, a transgenic
00:34:11.080
animals. It's very insulin sensitivity, and it has half the lifespan of a wild-type animal.
00:34:18.620
So when you say insulin resistant or insulin sensitive, are you always referring to muscle?
00:34:22.440
Are you referring to liver? How are you defining them?
00:34:24.880
Well, in this sense, it was everything. It was IRS, for example, IRS-1, IRS-2 knockout,
00:34:32.720
some of them only in the brain. So it was really insulin resistance everywhere.
00:34:38.740
Is IRS-1 found in the muscle and not the liver?
00:34:42.240
No, IRS-1 and IRS-2 are everywhere, but IRS-2 is more in liver and brain.
00:34:48.900
Yeah, they're selective. They sort of have selective expression.
00:34:52.780
Yeah, so I'll just translate. IRS-1, insulin receptor.
00:34:56.420
Substrate. So let's talk about exactly how the muscle takes in glucose. So we are walking around.
00:35:04.240
If I bolus you with glucose right now, and your blood glucose rises from wherever it is right now,
00:35:10.620
90 to 200. Let's say I give you an enormous bolus of glucose, I double it. So you're up to 180
00:35:16.880
milligrams per deciliter. This is a very high, screaming high level, which by the way, only
00:35:20.660
amounts to an extra few grams of glucose. But nevertheless, what is the chain of events that
00:35:25.480
leads to insulin being secreted and the muscle ultimately disposing of that glucose,
00:35:30.300
both actively or passively? Well, there'll be obviously a secretion to insulin that's relative
00:35:36.240
to your glucose level. And so the beta cell is the sensor. Right. And out comes insulin. And now
00:35:42.620
what is insulin doing to the muscle? And insulin through the insulin receptor will get translocation
00:35:49.660
of the glutphor. Those are the glucose transporters that are the major glucose transporters in muscle.
00:35:56.120
It will go from an intracellular pool into the plasma membrane, integrate it, and starts getting
00:36:02.980
glucose like crazy into the cells. And that happens quite passively, meaning once the GLUT4
00:36:07.560
transporter is translocated across the cell membrane, glucose can passively rush in, correct? It doesn't
00:36:13.460
require ATP to bring it in against a gradient of any sort. Correct. And in fact, it has its own
00:36:20.980
intrinsic activity that's not energy dependent. So it can go faster or slower by different ways.
00:36:28.140
Now, is there another method by which without insulin, we can get glucose into a cell that
00:36:33.740
somehow relies on AMP kinase? Not on AMP kinase, but there's non-insulin mediated glucose uptake. In
00:36:41.240
other words, there's a way for glucose to get up without the insulin. And we know that from hyperglycemic
00:36:47.220
clamp and from other things that when we can move the insulin or keep insulin level at basal,
00:36:54.020
and still there's a substantial glucose uptake that's happening. So yeah, we know that.
00:37:06.440
That's true. That's true. This NIMJA is the non-insulin mediated glucose uptake
00:37:11.360
is something that he's exercise dependent to. That's why now I understand your question. Is AMP
00:37:17.940
kinase part of the thing? And I don't know that. Yeah. I only have one patient in my practice who
00:37:24.480
has type 1 diabetes, but he is such an interesting patient because of his incredibly strict dietary
00:37:32.240
control and his unbelievable appetite for exercise. And I've never seen a higher level of adiponectin in
00:37:42.660
a human. I've never seen a higher level of sex hormone binding globulin in a human, which are
00:37:48.420
basically, and we know how much insulin he has because he injects it and he injects so little
00:37:53.160
insulin into himself and yet can seem to, you know, he has a hemoglobin A1C below six using six to eight
00:38:00.780
units of insulin a day. And so what got me, it got, that's what got me very interested in this
00:38:05.540
non-insulin dependent glucose uptake. Yeah. I'm not doing this research anymore.
00:38:11.080
I used to be in front of that. I, glucose itself can modulate glucokinase activity in the liver.
00:38:16.960
There's a lot of things that happening. And of course there's coordination between the fat and
00:38:21.200
the liver. And then I started being interested because we can do things to the hypothalamus and
00:38:28.440
take over this insulin and muscle and fat and liver. We can do it all from the brain.
00:38:36.260
Isn't that amazing? Well, just because I'm so fascinated by this and I think it will help the
00:38:41.760
listener to understand the complexity of what you just said. If I took an animal and put a lesion
00:38:48.000
into the ventral part of the hypothalamus, a normal animal, what could that do? What would that change
00:38:53.940
about its metabolism? Well, that would increase basically food intake and change a lot of the
00:39:01.160
peripheral physiology, but we do basically the opposite. We give insulin to the hypothalamus or
00:39:08.040
glucose or IGF or leptin. Okay. And then we see what happens to the periphery, although in the periphery,
00:39:16.560
those hormone levels are not increasing at all. And not only that, the liver is a good target to follow
00:39:23.300
because what you can do with the liver, you can do selective hepatic vagotomy. And everything that
00:39:30.480
you did through the brain doesn't work anymore because it needs the nerves. Right. So I'll explain
00:39:35.700
to the listener what that means. So the vagus nerve connects the body through this parasympathetic
00:39:41.040
system. And of course, if a patient has a liver transplant, or if you do an operation where you sever the
00:39:46.580
vagus nerve, you sever that connection between the central nervous system and the periphery.
00:39:51.980
Correct. And so we can do it experimentally and it will help us see if it really-
00:40:00.100
Or, yeah, or more nerve only. You know, it's the nerves because we do, it's not only vagotomy,
00:40:06.280
we do a little bit adrenergic too, but it's through the nerves and not through a chemical reaction on the
00:40:12.920
liver. You see, this is the problem with metabolism, Nir. The more I go into it, the less I know.
00:40:20.040
It drives me nuts. My absolute knowledge increases incrementally and my relative knowledge falls
00:40:26.320
precipitously. Well, I think I realized that you know what to ask. So you're undermining your own
00:40:31.960
abilities, but it's really, it's really the integrative metabolism is really very confusing
00:40:37.680
to explain. So we will define insulin resistance at the muscle, whether it be from an aged phenotype
00:40:46.420
or a diabetic phenotype, as a scenario under which a fixed amount of insulin hitting the insulin receptor
00:40:53.380
produces fewer GLUT4 transporters. Is that a fair definition?
00:40:57.960
Well, the definition of insulin resistance is really different and very simple. It's all about
00:41:07.740
the glucose uptake in the muscle, really. It's all about the ability of insulin to clear glucose.
00:41:16.860
Okay. That's the only way we define clinically insulin resistance, although that totally misses the
00:41:24.120
point because those insulin levels have different effects on different tissue. But for us, the
00:41:30.380
insulin sensitivity is totally related to the glucose uptake. So let me give you an example. So
00:41:36.520
when I use an oral glucose tolerance test with my patients, I'm a bit of a stickler. So if they take
00:41:42.620
their 75, you know, grams of glucola, I measure their glucose and insulin at baseline, administer the
00:41:49.040
glucola. 30 minutes later, 60 minutes later, 90 minutes later, and if I'm feeling aggressive, 120
00:41:55.460
minutes later, we remeasure the glucose, the insulin, and the FFA, and maybe even the C-peptide. But for
00:42:01.500
simplifying it, just the glucose and insulin. So let's assume you have two patients who start out with a
00:42:07.180
fasting glucose of 90 milligrams per deciliter and six insulin of IUs of six. They both get their 75 of
00:42:15.220
glucola. And let's, again, simplify this by just looking at one hour, what happens. Both of them at
00:42:20.560
one hour have a rise of glucose from 90 to 130 milligrams per deciliter. One of them did so with a
00:42:28.400
rise of insulin from six to 20. The other did it with a rise of insulin from six to 90. They've both
00:42:36.640
disposed of glucose with equal magnitude. Would you describe them both as equally insulin sensitive?
00:42:44.120
It's a little bit complicated. You know, first of all, so let me just say for aging, 120 is not
00:42:52.960
enough. In elderly, the glucose tolerance goes. So the rise in insulin is changing throughout normal
00:43:01.460
physiology and throughout individuals. And you might have missed some of the insulin peaks earlier on
00:43:09.300
or later on. Yeah. The third, looking at 30 versus 90 is a big insight. And you're right. I mean,
00:43:17.260
Joseph Kraft, who is a pathologist who has done a lot of work on this, he samples to five hours. Now,
00:43:24.600
again, clinically that's challenging in the regular day-to-day practice, but in the laboratory that's
00:43:29.860
feasible. And you're right. You can see so much happening beyond that. But I tried to pick an example
00:43:35.920
that was as egregious enough in its difference that what I'm trying to get is the difference in
00:43:41.140
hyperinsulinemia and whether that factors into how we think about insulin resistance.
00:43:45.480
Right. No, I don't think the clinical world is thinking like that. So I'm actually an active
00:43:52.860
endocrinologist. I still see on Thursdays if I'm in town teaching fellows in diabetes clinic in Montefiore
00:44:00.840
Hospital. So I am involved very much in this field. And I'll tell you that we rarely measure insulin in
00:44:09.560
any of our patients, but that's not really your patients. Okay. I'm talking about what's the use of
00:44:15.820
measuring insulin in type 2 diabetic patients. So it's a different issue. But yeah, this sounds like
00:44:23.420
there's a different insulin response to lower the glucose to the same extent.
00:44:29.540
Because the hypothesis would be that the patient with hyperinsulinemia is now demonstrating. I mean,
00:44:35.380
that's basically a harbinger of the first one who's going to struggle with glucose disposal.
00:44:40.100
That would be my hypothesis is the one who needed 90 units of insulin to dispose of glucose with the
00:44:46.200
same efficacy as the person who needed 30 is sooner rather than later going to have a harder time
00:44:52.140
disposing of glucose. Well, you know, there is another possibility that those are the people who
00:44:58.240
get other diseases first, like heart attacks or stroke. In other words, their insulin resistance
00:45:05.080
will affect a lot the way they do the atherosclerotic plaque and, you know, this hyperinsulinemia on
00:45:14.060
organs that might not be insulin resistant even, right? On cells that not come in insulin resistance.
00:45:19.360
So I would say that they could either the one who become diabetic or the one who are going to get
00:45:25.000
macrovascular disease much faster. Which brings it right back to our observation of glucose versus
00:45:30.740
insulin, micro versus macular vasculature. That's a very good point. So how does insulin signaling work
00:45:37.840
to get glucose into the liver? The liver has a different glucose transporter. It's a GLUT2
00:45:43.560
that is not translocated and that is the major way by glucose gets into the liver. So it's a little
00:45:53.320
bit different, but it's not stimulated the same. So it's constitutively expressed across the membrane?
00:45:59.720
It's not stimulated really by insulin as much. So it's more gradient driven to get the glucose from
00:46:07.240
the circulation into the liver. Yes. And that's where the portal blood is. So there it's very
00:46:13.180
sensitive to the increasing glucose concentrations. Well, that's very interesting because it certainly,
00:46:19.160
I mean, there's lots of evolutionary reasons why that would be a fail safe, right? Given the
00:46:22.820
importance of, you would never, ever want the liver to be denied glucose given that if you ever shut down
00:46:30.660
the liver's ability to make glucose, by my calculation, you could live about six minutes.
00:46:35.100
Yeah. Look, I was an intern of Sheila Sherlock, Dame Sheila Sherlock in England in a Royal Free
00:46:40.960
Hospital, very known pathologist. And she asked a group of us, what's the main role of the liver?
00:46:47.320
And I raised my hand and I said, it's to produce glucose. That would be my answer, by the way.
00:46:51.340
And everybody laughed at me and she threw shocks at them and stuff. And she said, just a minute,
00:46:55.740
why are you saying that? I said, because if you take the liver out and clamp the vessels,
00:47:00.540
the guy will die from hypoglycemia, which is absolutely true.
00:47:04.940
Yeah. Yeah. It's, um, I, you know, maybe it's just because I'm in the midst of writing this
00:47:10.780
chapter for my book about the liver, but I literally yesterday I sat here in my room and,
00:47:16.420
and penned out the calculation of 180 pound person with blood glucose of 180 milligrams per deciliter
00:47:24.020
clamp the liver. How many minutes until they die? It's about four under those, under those conditions.
00:47:30.540
Can you imagine that? Think about like what this beautiful organ has to do.
00:47:34.580
But you know, another thing to consider in your example, right? Uh, so for example, elderly
00:47:42.100
have enough insulin to suppress glucose production. Glucose production is easier to suppress
00:47:49.980
then it's suppressing lower level of insulin than stimulating glucose uptake in the muscle.
00:47:57.480
The liver is more sensitive than the muscle. And so elderly have the ability to suppress
00:48:05.720
hepatic glucose production because they have enough of insulin to do that. But when you start giving
00:48:11.960
them food during the day, they fail and they become glucose intolerant and diabetic. They might have
00:48:18.640
diabetes, although their basal level are well, just because of this, this enough insulin to suppress
00:48:27.840
glucose production and not enough to increase glucose uptake. So the sensitivity of the tissues is really
00:48:34.460
to insulin is really part of what you're describing. If you look at the basal, it's very different when
00:48:41.240
you look at the challenge. That's such, such a great point. Um, and I won't, I won't go down that
00:48:46.940
rabbit hole anymore because I, I, I would love to, but there's so many other things I want to talk
00:48:51.140
about in here. Let's, let's go back to metformin and let's do it now through the context of an
00:48:56.240
anti-aging drug. So there's going to be some people listening to this who already know everything
00:49:00.980
about you. If for no other reason than the efforts you've put into tame, obviously I want to have plenty
00:49:06.700
of time to talk about that, but let's back up for a moment. Tell me when you first realized,
00:49:12.140
Hey, this metformin drug that I worked on 30 years ago, it's not just a great drug for people
00:49:18.180
with diabetes. This could actually be a drug that helps someone without diabetes live longer.
00:49:25.260
So first of all, there were studies on the biology of aging in rodents. And the first guy,
00:49:34.100
which I'll be embarrassed now to forget, he's a guy from Leningrad that was the first to say,
00:49:40.640
I've done a rodent studies and animals with metformin, Anatoly. I'll remember it maybe later.
00:49:49.780
And he showed that a life extension, extension increases in variety of animals to which he gave
00:49:59.480
What was his hypothesis? Do you remember? Why would he, what would he, what drove him to do that?
00:50:07.960
It's even wasn't related to glucose metabolism necessarily. He thought that maybe there's an
00:50:14.120
anti-cancer effect and he looked at that, but then he got models that were hypertensive and they also
00:50:20.360
live longer. So he thought those are different effect. And then he considered to aging. But at that
00:50:25.860
time, this was in the eighties when he started that. And it bothers me that I don't remember his name.
00:50:35.320
I should take more metformin. And he was pushing, he was showing up in meeting and showing. And so
00:50:42.100
people have tried to do it in the United States and they showed that there's a significant effect
00:50:48.140
on insulin. By the way, the effect of insulin in animals is 10%, not like rapamycin is 24%.
00:50:56.620
So there's a milder effects, but in every study, they showed that health span is improved, you know,
00:51:05.460
by 50%. So the effect on longevity was less than the effect of health. By the way, that's perfect for
00:51:12.560
what I'm trying to say. I'm not for longevity. I'm just for health span, right? So if we can leave
00:51:18.360
healthy, healthy, healthy, die, that's fine with me.
00:51:23.500
Squaring, right. Squaring of the longevity. So he started Asimov. His name is Asimov.
00:51:29.640
So that's what Asimov showed. People have started looking at that. There are several studies,
00:51:36.600
three studies that gave it also to nematodes. They also lived longer. And there's several effects
00:51:42.500
on health span in the biology of aging. Now, the reason there's a lot of needle threading here in
00:51:51.980
my story here, okay? But I want to tell you the moment that I knew we have to do this study
00:51:59.900
was a publication, not in a very high impact journal, but it was an amazing study that could
00:52:08.240
be done only in the UK. Because in the UK, you can go into pharmacies and look at prescription
00:52:19.140
that they gave. And you could follow the mortality of those patients.
00:52:28.040
Because the NHS system allows you to centralize everything from prescription to usage to mortality.
00:52:34.860
Exactly. And they're probably, they don't need to be de-identified after mortality. When you're
00:52:43.560
dead, you're not private anymore. So they did this study. So what they've done,
00:52:50.040
there are four arms to this study. They came and took patients who are on sulfonylurea, 12,000 patients,
00:52:58.240
okay? And they matched them to 12,000 people without diabetes. Okay? Same pharmacies, same doctors,
00:53:07.940
controlling for some other things. And of course, the people on sulfonylurea had higher mortality
00:53:16.140
Right. Because of course, they had a reason to be taking the sulfonylurea.
00:53:19.900
Right. They had diabetes. So that's okay. Then they took 78,000 people on metformin and 78,000
00:53:29.600
people who were non-diabetic. Again, matching them.
00:53:33.900
And the 78,000 on metformin was metformin monotherapy.
00:53:39.380
Right. And they watched their mortality. So just to underline again, the people on metformin
00:53:48.600
had diabetes. The control didn't have. They were more obese than the control. They also
00:53:55.100
have more diseases than the control. But they had significant less mortality, 17% less mortality
00:54:03.440
in the metformin group. And, you know, the sulfonylurea group was, okay? So if you get less mortality
00:54:15.880
with metformin, when the setup is diabetes, that really shows that metformin has a very important
00:54:29.040
What was the median dose of metformin in those populations?
00:54:37.260
Well, they intended more, but the average was about 15 milligrams.
00:54:43.820
Yeah. No, 1,000 milligrams. I'm sorry. They, this is a discussion there. I don't think they
00:54:56.380
Because an elegant thing to do if you have 78,000 in your database is now stratified by dose.
00:55:07.380
They couldn't do that. And I really cannot answer you if you can get back to the data or not. I really
00:55:14.480
don't know. The dose we chose came from other studies. But, you know, that's not the only thing
00:55:22.460
What was the time course of that, by the way? Do you know how many-
00:55:27.060
So, five years exposure to metformin or five years of prospective mortality following?
00:55:33.860
No. Well, it's all, it was all a prospective study. Okay? It was all a prospective study. When
00:55:41.580
they started, okay, they went back, they looked at everybody on metformin.
00:55:46.900
Oh, I guess what I'm asking is, do we know how long they needed to be on metformin to achieve
00:55:52.460
Okay. So, we followed them for five years of mortality in a prospective cohort. But they
00:55:58.280
could have been on metformin for five years or 25 years. We don't know.
00:56:02.160
No, no. It's newly prescribed metformin. They were not more than five years.
00:56:09.100
Absolutely. Absolutely. No, they haven't been on metformin before. Those are newly diagnosed
00:56:15.860
So, Nir, that's a pretty, to be blunt, goddamn staggering result.
00:56:21.260
So, my metformin moment, nowhere near as dramatic as yours, basically came out of a research project
00:56:31.080
I did with two analysts in 2013. And I don't even remember what prompted the question. But there
00:56:38.680
was a question we had internally about what was the benefit of metformin. Oh, no, no. Now I remember
00:56:46.460
the question. The question was, was there a relationship between hyperinsulinemia and breast
00:56:51.240
cancer? This was the question we wanted to ask. And as we dug and dug and dug and dug and dug,
00:56:56.480
something kept hitting us over the head over and over and over and over again, which was with or
00:57:02.520
without diabetes, with or without obesity, with or without hyperinsulinemia, any way you sliced and
00:57:09.180
diced the data of people with type 2 diabetes with and without metformin, they got much less breast
00:57:14.340
cancer, which then dug us down a rabbit hole if they seemed to get much less cancer, which was,
00:57:23.860
Right. And there are hundreds of studies that show the association between metformin and less
00:57:30.740
cancers. And not only that, less all cancers, except prostate, by the way. Prostate is hanging there
00:57:37.080
maybe a little bit. And when we went, and I'll tell you later, but when we went to the NCI to make
00:57:43.480
them partners in this TAME study, it was really interesting. Can you tell people what TAME stands
00:57:48.120
for? TAME stands for taming or targeting aging with metformin. And it's a study that's designed to
00:57:54.820
prove the concept that aging can be targeted, but also, or mainly for me, is for the FDA to give an
00:58:02.760
approval to an indication that's like aging. The first time I heard about TAME was actually here
00:58:07.800
in this city. I was having dinner with Steve Osthead. It must've been in 2015, maybe 14, 15.
00:58:14.860
Steve is a gem of a human being. I consider him certainly one of the most important mentors in my
00:58:20.700
exploration of this field of aging. We're partners in many ways. He's a great guy.
00:58:26.080
He is, he is one of these guys that has, his knowledge is out of control. You can't ask him
00:58:32.120
a question that he doesn't know where to go for the answer. I have the highest respect for Steve
00:58:37.400
and can't wait to interview him here as well. But I remember him telling me about this. And my first
00:58:42.360
thought was, Steve, that's a crazy idea. The drug is free. Who the hell is going to pay for this study?
00:58:49.280
NIH can't pay for it because they don't consider aging a disease. Pharma can't pay for it because
00:58:53.720
there's no way to make money on it. I mean, I might pay like 10 cents a year for my supply of
00:58:58.440
metformin. It's a free drug. I said, you're doing the wrong study, man. You got to do this with
00:59:03.700
rapamycin. So talk to me about the challenges of this. This is, you're proposing something that is
00:59:10.660
really never been done before. Can I just ask you, are we going back to metformin? Because you asked
00:59:15.500
me about diabetes, but not metformin in action. Will you ask me later? Absolutely. I cannot wait to
00:59:21.680
dive into metformin. Yeah. We're not going to get off this topic for a while.
00:59:24.880
Yeah. So, so look, if I'm answering now, why metformin and not rapamycin?
00:59:31.320
Oh, you don't need to answer that question. I was just sort of teasing Steve that day.
00:59:34.400
Well, there are people who are asking, and of course, metformin, we have preliminary data.
00:59:40.040
We have the cancer. We have clinical studies, you know, clinical studies of metformin,
00:59:44.900
the diabetes prevention program, it prevents diabetes. The UKPDS, it prevents cardiovascular disease.
00:59:51.680
The Alzheimer literature, there are two clinical studies to suggest that in mild cognitive
00:59:58.780
impairment, it improves some domain, by the way, like name recalling. Asimov.
01:00:04.720
We'll, we'll up, we'll up your dose after dinner.
01:00:08.120
So there's lots of, and safety. Look, if we're going to have a new indication,
01:00:13.660
we don't want to kill anybody on the road. With rapamycin, we won't be sure. And it causes
01:00:19.860
diabetes and it causes a testicular atrophy and cataracts in animals. Okay. So we have to play
01:00:26.340
it safe. So I would only add one caveat in defense of rapamycin, which is with constitutive
01:00:31.100
dosing. Right. And, and you're, you're aware of the studies from John Manick, right? Yes,
01:00:37.180
of course. The last ones. Yes. Okay. So, so my view on rapamycin is it should not be dosed
01:00:42.800
every day. Exactly. It should be selectively dosed to target mTOR complex one, leave complex
01:00:48.480
two alone. Exactly. And I'll, we'll get back to that because I'll tell you what we've done
01:00:53.040
with metformin for the biology of aging part. So that's why the fact, you look, we are a bunch
01:00:59.780
of professors, including Steve Austin. We go to the FDA, by the way, beautiful movie by Ron Howard.
01:01:05.280
He went with us to the FDA, to the Senate. Wait, has it been released yet? This documentary?
01:01:10.400
A year and a half ago. It's called The Age of Aging. It's National Geographic. It's the best
01:01:16.960
movie that was done ever on aging. It's really quite incredible. Ron Howard is narrating it.
01:01:23.300
I remember, I'll tell you what, I was having dinner with Steve at some point during, he was
01:01:28.620
here in New York for that being filmed. Yeah. So, you know, so we're a bunch of professors
01:01:33.140
professors that are coming to the FDA and kind of telling them, you know, you know that aging
01:01:38.520
has biology, but this biology also can be targeted. And they said, so what? We said, well, if you slow
01:01:44.080
aging, then you prevent a bunch of aging-related diseases altogether. And I said, well, we're
01:01:52.160
interested to hear. And we went through this discussion with the FDA. I would say that the
01:01:57.760
most interesting part, and you'll appreciate it because you're diabetes centric. I see you're-
01:02:08.780
But I'm diabetes. I think of diabetes as a great example of what happens when you don't fix things
01:02:15.660
So we told them, basically we came and we said, we'll do a study. And what we're going to see is
01:02:21.580
cardiovascular disease and cancer and Alzheimer's mortality and diabetes. And I said, not diabetes.
01:02:27.040
You said, what do you mean not diabetes? I said, no, diabetes. Look, you diagnose diabetes. First
01:02:32.200
of all, you diagnose it on a chemical test. You know, you decide. And only 40% of them,
01:02:39.620
10 years later, will get complication. We're really not interested in diabetes.
01:02:45.640
Absolutely. Absolutely said it. And by the way, I should add that there's another bunch of people
01:02:52.260
who came to tell the FDA that they should allow metformin for prediabetes because the DPP said
01:02:59.460
metformin prevents diabetes by 30%. And the FDA said, well, if you think that's important,
01:03:06.800
why don't you make the diagnosis of diabetes in 5.8 hemoglobin N1C? You know, it's not up to us
01:03:12.420
to do that. And they wouldn't give them an indication for prediabetes.
01:03:19.620
That's a very counterintuitive point of view when you consider the long-term, not short-term. The
01:03:27.740
short-term cost burden of diabetes is relatively trivial, but it's that long-term cost burden that
01:03:34.360
You know, it's very boring with you because we have the same views. You're right.
01:03:41.860
So, yeah. So, okay. But so we had to adjust our study. We had to take diabetes as one of the
01:03:47.840
outcomes and put in and, you know, just increase the number and take diabetes out. It's not that
01:03:52.940
we're not going to follow diabetes, but the FDA is not interested in diabetes. So the, really the
01:03:58.340
challenge was how do we define aging in a clinical study? Because one view is, well, let's-
01:04:05.000
Because you can't use survival, overall mortality?
01:04:08.500
Well, there's no, there's no biomarkers to aging. All the diseases are, are, their major risk factor
01:04:15.920
is aging, you know? So how do you define it? And we basically did a lot of work and published a lot
01:04:21.620
of work and showed that, okay, let's, let's take somebody who has survived cancer and he's 65 to
01:04:30.020
80 years old. What's his chances of getting cardiovascular disease, cognitive decline,
01:04:38.160
mortality, right? The other things. And let's say it was 10. Okay. And okay. Now let's switch it
01:04:45.700
around. Let's take somebody who had cardiovascular disease. What's his chance of getting cancer and all
01:04:51.220
the others? 10. Okay. Let's take somebody with Alzheimer's. What's his chance? It really, with
01:04:56.720
aging, it doesn't matter. The disease you get first depends on, you know, your genetics and
01:05:04.740
environment. If you have a mother who's diabetic and you're obese, you'll get diabetes first. Okay.
01:05:10.160
But really, because, because we age biologically, you know, in different way, whatever it is, the next
01:05:18.020
disease, you're going to get the next disease. And we don't know what's the next disease, but that's
01:05:22.680
what we're going to prevent. That's sort of like, it's a really interesting idea you propose because
01:05:26.780
it's in lending, you would call that asset value correlation. So you'd say, well, let's say Nir comes
01:05:33.600
to my bank and he has a credit card and he has a car loan and he has a student loan and he has a
01:05:39.900
mortgage and he has a personal business loan. Which one is going to default first? Eh, I don't know.
01:05:45.700
I mean, I could sort of tell you typically people are going to stop paying their credit
01:05:49.340
card before they stop paying their car and their mortgage. But boy, once you default on
01:05:53.620
one, those dominoes start to fall very quickly. And so, so that would have what we would call
01:05:59.000
a very high asset value correlation of default. Yeah. So it's sort of like a, this is the same
01:06:03.500
for disease. Yeah. I think you're right. I'm saying it a little bit different. I'm saying
01:06:08.440
I'm agnostic to the disease. To which the first one is. Yeah. It's just. I'm agnostic. It doesn't
01:06:13.140
matter what you come and what, what you're going to have. I'm going to prevent whatever
01:06:17.200
it is. That's why we have a composite. Okay. A composite. And people get very prickly about
01:06:23.300
composite outcomes. Very. And I got it. I'm going to get on my soapbox for a minute here
01:06:27.840
because this pisses me off to no end when people get all bent out of shape about how you can't
01:06:33.540
have a composite outcome. And this is the bias against aging really. Because in the end,
01:06:40.120
what matters is how long are you alive and how long is your health span optimized?
01:06:45.800
So I'm sorry for, I made that rant as short as I normally could. Normally that would be a 10 minute
01:06:50.620
rant. Well, that would be a 10 minute rant for me too. Okay. Yeah, absolutely. And, and this is where
01:06:57.640
we get into trouble. I'll tell you what the other pieces, but we had our grant reviewed at the NIH and
01:07:04.220
unfortunately. And is this inside any of the groups except NIA? Like is NCI weighing in on this?
01:07:10.400
Yes. Yes. I'll tell you what we've done. I'll tell you what we've done in a second. Let me just
01:07:16.560
make sure that I say that. So our reviewers were not GRSI because we, everybody's involved and we have
01:07:26.500
14 centers. Okay. So everybody's involved. So the reviewers are from other place and they just,
01:07:32.680
they just, just a minute. You're saying that aging can be targeted and one drug can do it.
01:07:38.980
You're crazy. Okay. There's no such thing. Why don't you do three studies? One study is metformin
01:07:45.360
cardiovascular. One study is metformin cancer. One study. And we're saying no, because what are we doing?
01:07:52.020
We're trying to give aging an indication. Suppose we do it. It's just such an anthema to the way they
01:07:58.880
think. And I, I'm not saying that to be critical of them, right? But they're in a silo. I know.
01:08:03.680
Which is if you come to NCI, how can you care about anything but cancer? Right. I know the silos are
01:08:09.760
really, are really killers, but for us, so you, you could say, well, let's do all those studies. But for
01:08:16.080
us, we're calculating the power. I was just about to say the power analysis on that study
01:08:21.840
is going to quadruple your budget. No. Well, for what they do. Yes. For the silos. But for us,
01:08:29.480
it's not only, it's not only the budget. We don't want to stop this study. Let's say
01:08:34.380
that we show in two years that we, we delay cardiovascular disease. It's significant.
01:08:39.280
They'll stop the study. And they said, no, everybody now has to be on metformin,
01:08:42.480
but we wouldn't be able to show the FDA that we are aging. For us, aging is, stop telling us
01:08:51.560
diseases. We are going to have a cluster and we're just going to delay the aging. So we'll get the
01:08:57.600
health span extended by two, three years. That's what we're trying to show you. And the significance
01:09:02.560
is for the cluster, not for the individual disease. And if you tell me to do individual disease,
01:09:07.300
I need triple the, the budgets and I'm not going to get to the FDA with the indication for aging.
01:09:13.260
So it seems to me that the biggest challenge here is not the funding. It's not the study design.
01:09:19.460
It's the conceptual leap. It's, it's a completely different paradigm of how we think about delaying
01:09:26.420
death. Correct. Correct. Where, where do you stand today? So I'll tell you a few things. First of all,
01:09:32.440
we conceived it. I got my friends to what I call a prison, a French prison in Spain somewhere. We
01:09:41.340
were in a parador in the middle of nowhere in Spain for several days saying, what do we have to do in
01:09:48.100
order to open the field for aging, to allow us to get to treatments? And we decided several things,
01:09:55.200
but one of them is to go, to go ahead with time. By the way, I'm saying French prison because the food
01:10:00.280
was good, but it was in Spain. And we started, and I started getting those people, those clinical
01:10:06.940
people together. And we started really thinking through for what it takes, for what it takes.
01:10:12.900
And we had this whole academic and wrote papers in order to say how we're thinking, how we're thinking
01:10:18.760
of cluster of diseases, how we're doing power calculations for targets, aging and stuff like
01:10:24.900
that. We really spend a lot of time with the best people. Now, our friends came to us and said, just a
01:10:31.220
minute, your study is $70 million. If the National Institute of Aging is going to spend $70 million, that
01:10:38.860
means this, the National Institute of Aging is very small. It's just 3% of the budget, although we are 80% of
01:10:44.940
the diseases, right? Then we won't have money for the grants. And I said, well, what I'm going to do is
01:10:51.680
two things. First of all, half of the money is going to come from somewhere else. That's my
01:10:55.400
association with AFAR, where Steve and I are the scientific directors. And for AFAR, I got the
01:11:03.520
other half. So the $35 million is already raised, and that's mostly philanthropic. Right. And then we
01:11:10.240
went among the institutes. So NCI should chip in a bit. NCI, NHLBI, NIDDK. They didn't commit because
01:11:19.300
first they have to see the review, okay? Or they have to have the decision that the NDI wants.
01:11:25.500
I would tell you though, that the NCI director, who's a good friend of mine, is waiting for TAM to
01:11:30.820
come. You know, he's like, where is TAM? So the NCI has committed. It's basically a bunch of
01:11:36.320
contingent commitments. Yeah. I just want to say committed is the wrong word because they didn't
01:11:42.360
have a budget yet and the grant didn't come to them. But I know that they will give them money
01:11:47.100
because their head is, will do it. Yeah. So that's good to hear. So
01:11:53.000
when, realistically, when is the soonest you would begin enrolling for TAM?
01:11:57.740
You know, I'm waiting for something to know next week. And if next week goes well, so I just want
01:12:04.800
to let you know that we have an alternative. The alternative is non-for-profits. That the reason
01:12:11.440
they haven't joined us is that their charter is not to fund anything that the NIH funds. They want
01:12:19.240
something riskier. Of course. So if the NIH is not funding because they feel it's risky,
01:12:25.240
those will fund. So we can start anywhere. And it's, the answer is early 2019. Okay. We're basically,
01:12:33.960
all our centers are ready to go. How many centers? 14. How many subjects? 3,000. Age? 65 to 80. Any
01:12:43.440
limitation on comorbidities? No. In fact, well, there are a lot of limitations, but we're very
01:12:49.500
inclusive. But no existing diagnosis of cancer? No, unless they're cured. Okay. So you could be in
01:12:56.300
remission, but you can't have active cancer. Yes. Is it secondary prevention or primary of heart disease?
01:13:01.180
You could have cardiovascular disease, you know, in the past, if you're okay now. You could have
01:13:07.460
mild cognitive impairment and low speed walk will be a criteria. So in other words, we don't want the
01:13:15.520
people like in my study who will become centenarians because we're wasting time on them. We want people
01:13:23.700
who we know are kind of in the midst of aging. And we know that it's never too late to target aging.
01:13:30.040
So 65 years and up, five years studied, and you're going to randomize one-to-one or two-to-one?
01:13:37.920
One-to-one. And the placebo versus what dose of metformin? Two grams?
01:13:42.540
1,500. So, you know, the, so first of all, I should tell you that Merck company from Germany is
01:13:48.540
giving us the placebo and metformin. Right. So the drug is free. So when, when you say nobody's
01:13:53.520
interested, it's true, it's generic, but actually Merck has the worldwide license for metformin.
01:13:59.740
And they're actually giving supply to lots of studies because they kind of realize that this
01:14:06.140
is good. And do you think there's a difference between generic metformin and branded in terms
01:14:13.160
So they're really, this is kind of a, this isn't necessarily accretive to them because one can buy
01:14:18.980
metformin generically anywhere. They're not going to make more money from giving us the, well, you
01:14:25.020
know, I should say even now, a lot of the metformin suppliers have higher sales and a lot of them are
01:14:33.180
non-diabetic. So this thing, which is, which is bad for me because I don't want too many people to
01:14:40.860
know that, right? I want to do this study. I don't want, and I don't, I want people.
01:14:44.440
Well, you'll have, you know, I don't think hopefully it won't impair your, your recruiting
01:14:47.520
and the power analysis. I mean, it's funny, honestly, near, I would have guessed, but this
01:14:52.660
is, this speaks to the non-linearity and complexity of estimating power. You can't do it without the
01:14:57.500
tables. I would have guessed you needed a bigger end than 1500 in each group. You are using 80 or 90%
01:15:04.820
90% power. But I should tell you, look for every disease, we have almost a 30%,
01:15:10.860
effect. And we, we chose 22% effect. Okay. For every disease, we have preliminary data for the
01:15:18.760
Got it. So you lowered your threshold to call it 20% from 30%. And at 90% power, you've hopefully
01:15:25.960
powered this. You've got buffer both on your power and effect size.
01:15:29.860
Right. And, and again, we don't want to stop this study early either for one effect. So we carefully
01:15:37.580
thought about it. We asked for a grant for six years because we don't want to overdo it.
01:15:45.920
Okay. So it might finish in four or in six, but we have the flexibility to look at that.
01:15:56.440
No, we decided to do only in the U.S. because of communication. And because look, outside of the
01:16:05.940
U.S., people came and said, you know, we'll fund Tain. But how, you know, if they say after two years,
01:16:12.920
we won't fund them, you know, it's very different. Because, because if it's a center, they need to be
01:16:18.560
part of part of the power and we cannot afford to lose them. So we, you know, those and other
01:16:24.240
consideration, we decided to stick with the United States. So let's go back to what we really glossed
01:16:31.560
over, but now I want to dive into. Why do you believe at the cellular mechanistic level, metformin
01:16:38.540
is an anti-aging drug? So let me take you through that in a, I don't want to say schematic way,
01:16:44.860
because we don't have this scheme here, but in a way that maybe I think will be easy to think.
01:16:50.320
So I want to start by saying that studies have shown that some of the effects of metformin are
01:16:58.520
through AMP kinase, and some of them are independent of AMP kinase. Okay. Is it important not for
01:17:07.020
metformin, but I don't know which are the ones who are relevant more for aging. Okay. And it's hard to
01:17:15.980
know, and it'll get complicated in a second more. So metformin gets into the cell through a transporter
01:17:24.180
that's called OCT1. Okay. This transporter is not equally, equal in every cell. So unlike
01:17:33.480
fenformin that goes with other transporters and affect everything, metformin is peculiar in this
01:17:39.980
way, but we have the preliminary data and it binds to complex one in the mitochondria.
01:17:47.520
Does it do so preferentially? Does it gain entry preferentially into the liver in humans?
01:17:53.220
Only in the sense that there's a nice concentration of OCT1 in the liver, but not, not, but it's not,
01:18:00.980
I don't think it's the top other organs have. So basically it's more about OCT distribution
01:18:06.340
and expression maybe than tissue specificity. Well, it's more that I want, I want metformin
01:18:13.540
everywhere. Okay. I want metformin everywhere. And I'll tell you how I kind of proved that.
01:18:21.260
So now metformin binds to complex one in the mitochondria. I'll tell you that metformin has
01:18:27.140
some action, epigenetic action that are independent of the mitochondria. You can do it with what's called
01:18:34.420
row zero cells. You can, you can deplete mitochondria and see and measure things and you can measure
01:18:39.800
things even without mitochondria. Okay. Again, do I need them? What type of epigenetic changes do you
01:18:46.680
see in the row cell? In histone deacetylation. Okay. So I cannot argue that this can be important.
01:18:54.180
It's not important if we use metformin, but it's important if you want to ask me,
01:18:58.480
are the mechanism of metformin AMP dependent, mitochondria dependent.
01:19:05.100
So there's an HDAC property that we may not have even thought of before.
01:19:10.300
So it gets to the mitochondria and in the mitochondria, it basically changes ADP, ATP ratio. And that's,
01:19:18.420
a lot of it is important in the liver, but not only to the extent that there is an activation of AMP
01:19:27.360
kinase. And Nir, is there a demonstrable reduction in NAD to NADH in that cell when complex one is
01:19:36.040
inhibited? Yes. Yeah, absolutely. Those studies have been, have been done. So there's a lot that's
01:19:43.420
going through AMP kinase. And I would tell you that downstream of AMP kinase, there is mTOR. Okay. And
01:19:51.280
it depletes, decrease mTOR activity and increase autophagy. And there's a whole pathway that will
01:19:57.280
go to the pillars of aging. You know, I asked David Sabatini this question a month ago and where he
01:20:04.080
doesn't know the answer, but I'm hopeful that maybe one of the postdocs in his lab will start to figure
01:20:08.760
this out. I'm very curious about what the dose equivalent is between, in terms of purely looking
01:20:16.700
at the readout of mTOR inhibition, what is the dose to dose equivalence of metformin via AMPK versus
01:20:26.580
RAPA directly? And I haven't, I mean, David didn't know the answer, which tells me nobody probably knows
01:20:31.420
the answer. Right. Look, it's, it's really difficult. First of all, for example, lots of the
01:20:36.900
non-AMP kinase activities are on much higher doses of metformin. Well, that's my point is,
01:20:42.760
can you clinically match them? No, because you, you really don't know at the end how much metformin
01:20:49.520
is in the cell. What we're doing now, we're doing isolated cells. In other words, we treated animals
01:20:56.660
with metformin and we're taking isolated cells to just see the variability of, of metformin in
01:21:05.300
individual cells. Even amongst homogeneous tissues? Yeah. Like we take hepatocytes and look at the
01:21:12.620
variability of expression. Yeah. Right. So it's all kind of a important question, but, but the story
01:21:20.420
is still, I'll tell you the story because at the end, I'm going to answer you what is that doing for
01:21:26.160
aging? Okay. And I don't want to rush this story because this is a great story. You take your sweet
01:21:30.920
time. So think about it in a scheme. You have the metformin in the middle, getting through the
01:21:36.580
plasma membrane, getting to the mitochondria. And on the left side, let's say there is the AMP kinase.
01:21:43.420
Okay. Now in the right side. Oh, sorry. Just for the listener, explain what AMP kinase does
01:21:49.240
at the high level. It's, it's a hormone of what it's a hormone of nutrient deprivation. And therefore
01:21:55.740
it tells the body to do what, like when you don't eat for a day, AMPK goes up. Why?
01:22:02.260
Well, but it's also an exercise mimetic pathway, right? Yes. That's what happens with, with exercise
01:22:10.060
really. That was the, the hope of what AMP kinase is doing, but it's a nutrient sensing that is in part
01:22:17.280
upstream of mTOR. Okay. But the other side of metformin is what happens to the mitochondria because
01:22:24.780
in a way, and I hope I won't regret saying it here, but metformin is a weak cyanide.
01:22:32.720
Okay. Look what cyanide acted at complex four. Right. But right. Oh, you just mean more broadly
01:22:40.180
speaking in inhibiting the ETC. Right. It inhibits. So there is less ROS production. Okay. And then
01:22:48.840
there's less inflammation and there's other things that's going just because the mitochondria
01:22:54.780
is less oxidative pathway going down. So this is a great example of why binary thinking doesn't very,
01:23:02.100
doesn't do very well in biology, right? It can't be all or none. Well, so now I can go on and on
01:23:10.420
and connect all those. Please do. To eventually the pillar of aging, but I want to insert another
01:23:18.720
thing because other things are happening. For example, insulin levels goes down, right? Why is
01:23:23.860
it just due to the reduction of hepatic glucose output? I'll tell you why I think. And then also
01:23:29.980
inflammatory factors are going down and there's a whole NF kappa B action of metformin that might be
01:23:38.880
part of the ROS and part could be independent even without mitochondria. Okay. It's that confusing.
01:23:48.180
But this is the point I want to make. I don't know which one of those is important for aging,
01:23:53.660
but parts of what you're measuring is the following. You fix the aging on a cellular level. Okay. So the
01:24:01.540
younger, the cells are younger. A lot of things are correcting themselves.
01:24:07.440
So I think at the end, the lower insulin levels, the low inflammatory are not necessarily a direct
01:24:15.680
effect. And that's why we're, we're fighting all the time about what metformin is doing, because
01:24:19.980
you can measure lots of things, but the things you're measuring are because aging was fixed.
01:24:25.080
And once aging is fixed, then there's whole hemodynamic readjustant or whatever you want to call it.
01:24:33.320
And then you're measuring that everything, and this is not only typical to metformin,
01:24:38.320
this is with rapamycin, with resveratrol, you also can see that there's a lot of things that are
01:24:45.420
improving themselves. And I think we have to get used to the fact that when you have a drug,
01:24:52.940
that we argue what it's doing, because everybody's measuring something, some of it is true,
01:24:58.740
but it's like secondary. It's, you fixed it. How did you fix it?
01:25:02.740
Yeah, it's true, true, and unrelated. And it's funny you mentioned those three,
01:25:05.980
which again, I think speaks to an advantage you have with TAME. So when you look at rapamycin,
01:25:12.800
resveratrol, and metformin, the big advantage of metformin is you already know the dose and the
01:25:20.640
frequency. With rapamycin, over dinner tonight, I'm going to give you my philosophy on the dose and
01:25:27.740
the frequency, and we can discuss it, but I can't demonstrate it to you with anywhere near the
01:25:32.340
validity that you could do the same with metformin. I had a wonderful discussion with David Sinclair,
01:25:38.320
and bioavailability came up on resveratrol, right? So maybe all the trials that say resveratrol is
01:25:43.220
meaningless are simply not looking at what happens if you get enough resveratrol in the right place.
01:25:48.100
And again, it's amazing to me how many times in biology we can make mistakes of the first order
01:25:58.020
because of a third or fourth order omission. And this, I guess I don't think I realized it until you
01:26:05.720
just gave that explanation, the value of effectively millions of patient years worth
01:26:14.020
of data on metformin, not just from a safety standpoint. By the way, billions, it's billions
01:26:19.240
of years. Is it billions? Yeah. So billions of patient year data on metformin. I know that from
01:26:24.900
an FDA standpoint, the highest priority is safety. That's a low bar to cross. The more interesting
01:26:30.620
one from the standpoint of this study is actual efficacy. Right. And it seems like if I'm hearing
01:26:35.680
you correctly, metformin is an amazing B student. Let's not be insulted by that. What do I mean?
01:26:41.120
Are there better ways to inhibit ROS if you want to hammer the ROS chain? Probably. There's clearly
01:26:47.320
better ways to inhibit mTOR if that's all you want to do. Are there better ways to modulate HDAC? Yes,
01:26:53.680
I'm sure there are. But it might be that maybe part of metformin's beauty is it does so many things
01:27:00.260
at a B plus level. Never it's an A student, but it's not a D student. And it's never, you know,
01:27:06.340
I mean, I'm sort of thinking about this sort of in a tongue in cheek way, but it's,
01:27:09.800
it seems to do so many things reasonably well. Well, I call metformin a tool from my perspective.
01:27:16.580
It's just a tool to show that we can target aging because I think that there'll be much better
01:27:23.880
drugs and combination drugs than other in the future. Human lifespan is 115 years. We argue.
01:27:30.400
Maximal lifespan. Yeah, maximal lifespan. We argue because there's somebody 122, but you know,
01:27:35.120
there's a statistic thing. So, okay, we die before the age of 80. So there are 35 years
01:27:40.940
that as a species without, not that we cannot change more, but just now without thinking too much
01:27:48.300
futuristic, long hanging fruit that we can do. And metformin is the perfect tool to start showing
01:27:56.100
the proof of principle here. But the future is much better. It's just, you have to,
01:28:01.900
to pave the road here. This is a beautiful pivot to something else I want to discuss with you,
01:28:07.020
because unfortunately I could talk about metformin for three hours, but there's so many other things
01:28:11.860
I want to discuss with you near based on your work. And you just alluded to one, which is the work that
01:28:17.900
you and your colleagues have done on centenarians has been very influential in my thinking. So as I think
01:28:24.640
about aging clinically, I ask the question, start with the existence principle. What does it mean
01:28:31.640
to live a long life? Is there proof of this having existed? And there is, we have centenarians,
01:28:39.320
they exist. My hypothesis, when I first started reading your literature, which was only about five
01:28:46.780
years ago, my hope, I should say, not my hypothesis. My hope was that whatever genetic benefit
01:28:54.160
they had, which it became very clear to me very quickly, that this wasn't about what they did.
01:29:00.460
In fact, they seem to have almost near immunity to the worst behaviors imaginable. My fear,
01:29:06.300
when I read your first paper, which was a review paper, I can still see it. And I still remember
01:29:11.400
where I was sitting in a Sheridan hotel reading it. My fear was whatever blessing they had,
01:29:20.620
it had nothing to do with chronic disease. And it had to do with something nebulous. And they had
01:29:26.800
complete immunity from chronic disease. And they just died in car accidents. Like they eventually
01:29:31.260
just died because something else tripped them up. And what I took away from your work was no,
01:29:36.220
their genetic gift was a phase shift. And when they got chronic diseases, they still died of heart
01:29:41.840
disease. They still died of cancer. They still died of Alzheimer's disease. They simply got a 20 year
01:29:46.440
bonus, if not more, maybe 29 on average, you could calculate, call it a close to 30 year bonus.
01:29:54.020
Well, of health span. Yes. Yes. Because completely functional life.
01:29:58.060
Because they had compression of morbidity. So it's not only that they lived longer and they lived
01:30:06.920
Quicker at the end of that. And you know, it's interesting, the CDC, the Center for Disease Control,
01:30:11.840
have looked at the last two years cost of life of people, you know, with different stuff. So
01:30:18.000
they looked at people who die at 70 and after a hundred. And the cost of dying after a hundred was
01:30:25.800
third of that of dying in 70. So it's not only in our study, there's actually evidence.
01:30:33.920
To suggest that the medical, and by the way, those, when they were 70, they didn't go to the doctor.
01:30:39.820
Okay. So the, and, and this is the base of this concept that's called the longevity dividend.
01:30:46.520
Okay. What, what will happen to society if we'll actually be healthier for two and a half years?
01:30:51.420
And, and the benefits are immense. You think only of a, you know, so we pay social security more and
01:30:57.500
stuff, but there are seven trillions dollars just in saving of medical costs. If you could just
01:31:02.940
live healthier. So I know you don't spend an enormous amount of time anymore thinking about
01:31:08.060
the centenarians, you know, your literature follow it very closely. You, you definitely are spending
01:31:12.680
much more time talking about and writing about the things that we just discussed, but if you could
01:31:22.840
Well, no, I think that's, what's interesting to people now. And I'm very happy about that,
01:31:27.780
but I just got the, you know, the longevity, the Ibsen longevity price. And my talk was actually
01:31:33.080
about centenarians with a little bit of my hypotalamus stuff that was related to something,
01:31:38.360
but the centenarians are, and we have lots of grants on the centenarians because, you
01:31:44.800
Is that talk, by the way, is it something that people can watch?
01:31:51.480
It's a real, I thought about, about this talk. It was fun for me to give because it was
01:31:55.780
reflective a little bit to, you know, one of the things that's always funny for me is people
01:32:00.980
say, oh, you know, I have, I can measure this thing. I'm sure that centenarians, they have,
01:32:06.680
they have high level because high levels are good. And I had to put into rest the fact that
01:32:12.060
the genetics of centenarians is really great for me. But the phenotype is not because you have a
01:32:20.600
hundred years old and you can measure something that can reflect what brought you here or the fact
01:32:27.260
that 30% of them are going to die in the next year. So it could be a marker of,
01:32:31.820
of death and not of longevity. Yeah. Their phenotype makes, doesn't interest to me. That's
01:32:38.940
why I have their offspring because their offspring will have the phenotype or half of their offspring
01:32:43.320
will have the phenotype. But those things were something that was nice because so many people
01:32:48.340
are saying, you know, we should measure in centenarians. No, we are, we're doing a longitudinal
01:32:51.800
study on their offspring and their offspring are equal everywhere to our control group. They just
01:32:57.220
have half of the diseases. Although you, by the way, that's a really interesting point, Nir. I never
01:33:03.280
once thought of that. I never, what you just said that if I have a hundred year old centenarian in my
01:33:09.160
study and he or she has a CTEP mutation or an APOC3 mutation, and I look at the predictable
01:33:16.700
phenotype because I know what you should have if you have that mutation. Hypofunctioning APOC3 should
01:33:22.640
have low triglyceride, but technically without a little more longitudinal legwork, I don't actually
01:33:28.340
know if what I'm measuring is a result of that. But that said, there must still be some benefit in,
01:33:36.660
you know what, now that I'm saying it, I realize you can't do it. The dream state would be to have
01:33:41.600
health records and phenotypes for centenarians that go 30 years back. In other words, it would be
01:33:46.180
beautiful to follow a centenarian from 70 to a hundred with phenotypic data. So that's why we
01:33:52.380
have the longevity study. It's a longitudinal study of offspring of centenarians and people without
01:33:57.820
longevity. And we're going forward, we're already 10 years into the study and we're starting, you know,
01:34:04.920
to see the differences between those guys. It's different population. They are aging slower. Okay.
01:34:11.120
The children of centenarians. So we have some of these things in mind. What are the most important
01:34:17.680
genetic differences between those either centenarians or offsprings of centenarians
01:34:23.600
and the rest of us? So it's very interesting. And so this is a part that you haven't heard so
01:34:29.640
from, but it's actually the growth hormone IGF axis. We have probably 60% of our centenarians
01:34:39.600
have genomic reasons. So let's explain the normal path of that. So the pituitary gland
01:34:46.560
makes GH. It tells the liver primarily to make IGF. Right. It binds to a receptor, right? In the liver
01:34:53.240
and IGF. And so some of the effects of the growth hormone system are through growth hormone
01:34:58.840
itself. And some of it is through IGF one level. Both of them are decreasing with aging. So in this
01:35:07.940
system, we identify, you know, more than 60%. And I think I'm underestimating. Okay. It's more,
01:35:16.080
it's probably more, but I didn't really calculate who has several mutations. You know, I can calculate
01:35:22.220
how many mutations there are, but not the overlap of the mutation. So I'm saying 60%, but it's the
01:35:27.520
most common genomic alteration in our centenarians. And I have to tell you- And where is it specifically?
01:35:35.160
I'll tell you in a second. And I want to just to tell you, I never, I wrote grants on that
01:35:40.820
because I thought, because there's preliminary data in nature, right? The small dogs live longer
01:35:47.700
and the ponies live longer. And when you mutate growth hormone or, or they're born dwarf,
01:35:53.920
they live longer. And when you give more growth hormone, they live shorter. So there is a lot in
01:35:58.160
nature, but the human data was really confusing. Some diseases, you know, when you have high IGF,
01:36:04.320
you have more cancers, but you have- Less Alzheimer's disease, less cancer. I mean,
01:36:08.520
sorry, less heart disease and less diabetes, but more cancer. Right. And mortality, in mortality,
01:36:13.500
it's like in the middle, you know, a little bit tending to more from, you know, from cancer.
01:36:18.600
By our analysis, which I think pulls all of your data, we found that there was an,
01:36:23.820
a U-shaped mortality curve with the nadir being between 60th and 80th percentile of all-cause mortality.
01:36:31.220
So I want to tell you the problem with this association. On one hand, an individual that
01:36:38.780
age quickly. Okay. Their growth hormone IGF goes down quickly. Okay. So you would measure falsely low
01:36:51.660
IGF-1 level. If you catch them on the wrong side of their aging curve. Right. That wouldn't fit our
01:36:58.120
theory that low IGF is good because that's their, their accelerated aging. Yeah. So this is a problem
01:37:05.920
with an association study like that. We discovered, first of all, that when we take our centenarians,
01:37:15.880
so they're, they're in our study because they've been healthy at age 95, living independently. We take
01:37:21.700
them at any age, but that's what they have to do. And we just look at those with the highest IGF and the
01:37:28.420
lowest IGF-1 level. Those with the lowest IGF-1 level live twice as long. Those are already the
01:37:35.420
centenarians, but only women. Men do not. And every example that I gave you, there's a sex
01:37:43.160
difference. The growth hormone IGF is very sensitive for women or for females.
01:37:48.900
Sorry, Nir, let me ask you another question. It's very difficult clinically to measure GH because
01:37:55.260
So whenever you're saying growth hormone, are you really saying IGF, which is easier to measure?
01:38:00.720
No, because I'm going to talk sooner, but not what I'm measuring, but where the mutations are.
01:38:07.800
Okay. But to repeat what you just said, the difference between men and women, was that based
01:38:16.240
But we discovered in aging, we did a huge faux pas, okay, that we are now correcting. We,
01:38:22.800
we studied in our labs, males only. We had excuses why females are menstruating. We don't know
01:38:30.720
their effects. And we're all discovering, look, even rapamycin that really works everywhere is
01:38:37.760
better in females than males. But ACABOS is in males, right? There are examples where we totally
01:38:46.000
miss the sex effect. And growth hormone IGF is a perfect example, except those mice that are the
01:38:52.780
snail mice or the Ames miles. They have a pituitary problem, which makes them, I think,
01:39:00.560
sex confused. So, you know, they have so many other alterations, but sex difference is important.
01:39:07.320
We also showed that those women with the lowest IGF one level has much less cognitive problems,
01:39:14.260
you know, third of the cognitive deficiencies of those with the highest IGF.
01:39:19.000
All right. Okay. So we had to grab our second round of Topo Chico there, which by the way,
01:39:23.140
I didn't even ask you up front. This is your first time having Topo Chico, right?
01:39:28.120
I mean, this is, there are a few things that bring me as much joy as introducing people to this bottled
01:39:35.060
The Perrier is much milder. I like to feel the bubbles.
01:39:41.280
Well, I would, I think one thing we should consider for TAME is if we can have an arm that also
01:39:47.240
includes Topo Chico. So there's a placebo, there's a metformin, and then there's a metformin plus
01:39:53.060
Topo Chico. And the question, the hypothesis will be, does that somehow enhance lifespan? Because even
01:39:58.900
if it does not, I predict it will enhance happiness.
01:40:01.640
Well, I have to tell you, I'm an advisor to the prime minister of Singapore. Singapore is a place that
01:40:07.160
can, you know, plan the future. And before going, I said, why don't you ask me questions? And one of
01:40:15.880
the questions, shall we put metformin in the water or in sodas? Now, good to ask, you know, the answer
01:40:23.560
is no, obviously, but it's good that you're thinking that way. So metformin...
01:40:29.040
And should you change your mind, I think you now know which soda it should go into.
01:40:36.080
Oh, I'm sure we can, yeah. So back to sort of what you were saying, this IGF male-female
01:40:42.460
disconnect, let's keep going down that rabbit hole.
01:40:44.820
So I was saying that one of the worries about low growth hormone in IGF is the effect on the muscle,
01:40:50.700
because people think that growth hormone affects muscle function, muscle size. And we found that in
01:40:58.140
females and males, the IGF-1 level is not associated with better or worse,
01:41:04.860
lots of muscle function, including grip and getting out of chair and, you know, other things. So maybe
01:41:11.400
the effect of low IGF and aging are just as good as having a higher effect of IGF on muscle. It just
01:41:20.000
weighs itself out. Okay. But then our study is genetics. Okay. That's what we try to do. And
01:41:26.820
several years ago, almost, I guess, a decade ago, we found clusters of mutations in the IGF
01:41:37.240
receptor. Those were new mutations that haven't been found before, but we found them in nine of our
01:41:44.360
centenarians, which was 2% of our centenarians. And that was kind of a proof of concept for us
01:41:51.440
that clusters of mutations that are functional is what we really need to look for, rather than
01:42:01.260
like everybody's doing, doing GWAS and find, you know, something intragenomic somewhere.
01:42:07.020
And this was also the first proof of concept that the growth hormone IGF could be relevant to human
01:42:13.160
aging. People that those 2% of our, those nine people had higher IGF-1 level because they were
01:42:21.940
resistant, right? It's the IGF receptors. They were resistant to IGF. So their level was a little bit
01:42:27.120
higher, but they were significantly shorter than others. Which is a great explanation of how that
01:42:35.220
phenotype would play out. You would say, well, how can they be short statured with high IGF? And the
01:42:41.260
answer is if the IGF isn't as effective at the receptor. Right. But remember that most of our
01:42:47.460
people with low IGF are doing better. By the way, we take the people with the IGF- Sorry, men also,
01:42:53.360
or just women? Two men in those nine people. And by the way, then there are dwarfs, human dwarfs,
01:42:59.100
that are called Laron dwarfs, that live in Ecuador. And Hassi Cohen and Volter Longo and some of the
01:43:07.540
people in Ecuador were looking, basically were trying to find if they live longer, too few of them
01:43:14.320
to really know. But they have less cancer and less diabetes, you know, significantly less. So
01:43:21.300
there's other evidence from humans came after hours that, that there is at least less age-related
01:43:28.040
diseases in those people. They certainly didn't live a better life in any way that we could
01:43:32.200
assess, correct? Right. I mean, we always joked that they weren't happy with the fact that they're
01:43:40.840
short. So they drank a lot, and that's the alcoholism. And then when they crossed the road,
01:43:46.960
nobody saw them. So then- They died of more trauma.
01:43:50.500
But I think it's really not true. So I met some of them. We were in a Vatican conference. Everybody
01:43:58.080
has to bring his patients. And Longo brought somebody from Ecuador, and I brought a centenarian
01:44:03.820
from Rome. And the guy that he brought told a different story. He wasn't unhappy. He was also
01:44:11.740
happily married with a big woman and had children. So I don't know.
01:44:17.700
Is the defect in them at the- Growth hormone receptor.
01:44:22.900
So they make a normal amount of growth hormone. Their liver doesn't acknowledge it.
01:44:26.640
A high amount of growth hormone because it doesn't work.
01:44:28.420
The feedback loop. Yeah. So they have lots of growth hormone, but it's not being expressed
01:44:34.400
Right. And so they have no IGF. So we published last year a paper that took us 10 years to write.
01:44:41.400
And basically, we were looking at a relatively common mutation. I'm saying common because it's
01:44:49.580
like 3-4% in the population where they have a complete deletion of exome 3 in the growth hormone
01:44:56.980
receptor. Okay. So one of the exomes, you know, one of the things that are important for the
01:45:03.560
integrity of this hormone, right, is deleted. And of course, you would think that that means
01:45:11.840
that the growth hormone is less effective. And Giletsmon, who was a fellow with me, brought me
01:45:19.560
this data to suggest that while it's 3-4% in our control population, it's 12% in our centenarians.
01:45:28.480
So I asked, so what's the IGF-1 level? And he showed it's lower. And I said, and what's the
01:45:34.880
height of the people? He said, well, that's the problem. They're much taller. So I said,
01:45:40.260
I cannot do anything with this study. It just makes no sense. I don't know how to write it.
01:45:45.860
So the people with lower IGF, but the mutation was in the exon of...
01:45:50.600
Of the growth hormone receptor. Okay. So they had lower IGF.
01:45:54.120
So it was a dysfunction of the receptor in theory. So less IGF. And we know that it was fully
01:46:00.540
penetrant all their life. In other words, there's no chance that it didn't start showing up until
01:46:05.300
they were an adult. Well, we'll come back to that. But the mutation didn't change.
01:46:10.320
And by the way, just give me some numbers here. How low are their IGFs?
01:46:13.440
I don't remember. Directionally. Like, are we talking about like less than 100?
01:46:19.160
Okay. Yeah. 100 is about the median level of IGF for somebody over 65.
01:46:28.900
Yeah. I think in the studies that I told you, the average or the mean or whatever was 94,
01:46:35.140
something like that. I don't remember to answer about those people. Okay. Now? Okay. So he said,
01:46:41.800
what to do? I said, well, first of all, what you do with genetics, you do replication study.
01:46:46.340
You go to other populations and you see what's going on there. And second, you do a functional
01:46:51.860
study. Let's see if it's really a functional mutation. So it took almost 10 years, right? And
01:46:57.880
in 10 years, we replicated the data in three other populations, in Amish, French, centenarians in the
01:47:07.180
CHS here in the United States. And in all studies, the people that live the longest had much more of
01:47:15.040
those homozygosities in the growth hormone receptor. So that was a great validation.
01:47:21.420
Second, the functional. So Hassi Cohen, my partner in USC, we send him the lymphoblasts of our patients,
01:47:31.360
the affected and not affected. And he is a growth hormone IGF expert. So he incubated them serum-free,
01:47:39.460
so without stimulation, and with growth hormone, and looked both at activation and proliferation
01:47:45.380
by growth hormone. So in serum-free, without stimulation, they had less activation and less
01:47:53.120
proliferation, half of normal, suggesting, yeah, that's the mutation. That's the function.
01:47:59.960
When he incubated them with growth hormone, it totally switched.
01:48:04.440
I'm sorry, but going back, you talked about proliferation, but was there a functional
01:48:09.420
difference in the lymphocyte in addition to its increase in number?
01:48:13.820
No, there's, yeah, the first was activation by phospho-ERC and some of the, okay, some of the-
01:48:23.360
No, no, specific to what growth hormone is doing, but ERC, proliferation, it's a, you know,
01:48:29.840
But when he incubated it with growth hormone, it was the opposite.
01:48:35.440
Rather than this low proliferation, low activation, it was high activation, high proliferation.
01:48:47.480
So with high growth hormone, something has changed in the activation.
01:48:54.020
From low activation, it jumped to high activation for reason with the, you know, the molecular
01:48:58.220
mechanism, the real mechanism we don't know really, but that's what happened when you have
01:49:08.220
And then when growth hormone got down for the rest of their life, they shut off.
01:49:18.380
Then Yuxing Su, who's a geneticist that's working on this, she was interested in microRNA.
01:49:24.360
That's another, you know, epigenetic thing that comes.
01:49:28.240
We haven't been thinking about it, but those are RNA that comes from certain region of the
01:49:33.440
gene and they bind specifically to active region of the gene and they modulate it.
01:49:39.940
Well, 30% of our centenarians have clusters of microRNA that are overexpressed by a lot, by
01:49:52.380
One of them, for example, microRNA 142, that's increased by 35 fold.
01:50:00.240
When you incubate it with cells, it prevents the phosphorylation of the IGF receptor, decreases
01:50:10.780
some other signaling, FOXO signaling, and some other stuff dramatically.
01:50:15.480
So there's a microRNA targeting of the growth hormone IGF receptor in about 30% of our centenarians.
01:50:23.220
Then 22% of our centenarians have mutation in FOXO3A.
01:50:38.160
FOXO3A is another, how would I say, just housekeeper.
01:50:45.540
Housekeeper that lets in good stuff and change things and put things in stop.
01:50:53.440
It's too complicated to go more, but it is part of the insulin IGF.
01:50:57.400
It's very important, the transcription factor at regulating homeostasis, cellular homeostasis.
01:51:04.600
But isn't FOXO the most prevalent genetic difference?
01:51:10.720
If you were to just isolate them by genotype, if you look at CTEP and C3 and FOXO and GH and IGF,
01:51:18.120
I mean, my recollection is that FOXO might be the single most prevalent of the...
01:51:22.180
Well, FOXO, I'm not sure that it's true, but FOXO3A is common in all centenarians' population around the world.
01:51:36.300
In fact, what we're doing now, when we have the exome sequencing of all our subjects,
01:51:45.580
the important thing to do is to assign them to pathways.
01:51:50.700
Because, you know, we're doing something really silly with genetics.
01:51:54.560
When we had this GWAS, we said we have million SNPs around the genome.
01:51:58.560
We'll find the diseases, every disease in the world.
01:52:00.820
And one of the stupidest things we did, we took one SNP at a time.
01:52:10.840
And in certain population, down this pathway, there'll be another SNP that will change the function.
01:52:19.860
Our analysis now is totally different than how we started.
01:52:23.700
But this, you know, I mean, I agree with you completely,
01:52:26.580
but I don't think most of the world is listening near.
01:52:28.680
I mean, if I had a dollar for every time one of my patients came with their, you know, complete sequence
01:52:35.820
and, you know, they want me to interpret them, I have the same discussion so many times.
01:52:45.160
To my last counting, maybe 78 of them have a deterministic relationship with a disease.
01:52:53.660
Because if you had any of them, we would know by now.
01:52:56.920
There's no chance you got here with Huntington's disease and we sort of missed it.
01:53:01.180
Or there's no chance you have some inborn error of metabolism that somehow got missed.
01:53:08.680
And, you know, it's hard to explain to people how multifactorial these issues are.
01:53:16.860
And I find myself, maybe you do as well, somewhat frustrated by these discussions and the overemphasis
01:53:24.000
on this genetic, you know, it's a little bit of the drunk in the streetlight problem, right?
01:53:29.980
When the guy is standing below the streetlight and you say, what are you doing here?
01:53:36.480
And he says, no, but this is where the light is.
01:53:38.360
So let me not increase the complexity, but give you another ammunition, okay?
01:53:44.120
So we did, you know, now several years ago, because of funding, we did our 44 best, you
01:53:52.380
know, first centenarians, their whole genome sequencing.
01:53:59.200
We just have 44 centenarians and we do the whole genome sequencing.
01:54:02.840
And our question was, do centenarians have the perfect genome?
01:54:08.100
I mean, maybe one out of 10,000, they just don't have all this crap from the GWAS, those
01:54:18.240
And we went to this data set that's called ClinVar.
01:54:22.320
ClinVar then had the 15,000 pathogenic mutation that most probably will cause a disease, okay?
01:54:32.840
And our hypothesis is that our centenarians don't have any of those, okay?
01:54:41.320
44 centenarians had more than 230 mutations between them, another five to six mutations
01:54:53.280
And none of them had this disease in 100 years of life.
01:54:57.620
And some of those mutations, I'll give you the best example there for Parkinson and cancer
01:55:06.280
We have two ApoE4 100 years old people that the textbook would say they're demented at
01:55:17.980
Do you think this at all explains the LPA uptick we see?
01:55:22.200
Because, you know, one of my favorite topics is lipidology.
01:55:26.000
And of course, LP little a is a very virulent lipoprotein.
01:55:30.500
And yet centenarians seem to have more of it than the general population.
01:55:34.260
So we actually showed in a paper because we found a way.
01:55:42.560
So basically, obviously, we can have mutations that are protected because they have slow aging
01:55:58.520
So we noticed that when you look cross-sectionally, I hope I can make it very simply.
01:56:06.560
When we put any genotype cross-sectionally, in other words, we have all the ages from 50 to 112 is our oldest.
01:56:20.080
If we see pattern that the genotype is declining with age, we know it's killing people, okay?
01:56:27.480
If we see that it's kind of monotonically increased with age, like with the-
01:56:34.140
Then means the people who are surviving are surviving with this mutation.
01:56:40.340
Like the example of growth hormone receptor going for 3 to 12 in a monotonic way.
01:56:51.540
And this is the most confusing of them all, because I don't see any compelling evidence
01:56:59.000
that LP little a is anything other than atherogenic.
01:57:02.540
And so it begs the question, why would it concentrate in centenarians as opposed to just rise commensurate
01:57:13.500
First of all, we show cross-sectionally that LPA drops until the age of 80 by half.
01:57:26.640
And then you look at that and you kind of try to understand, just a minute, now this thing
01:57:31.820
that killed, now all of a sudden centenarians have even more.
01:57:50.320
Are you saying that the thing that LP little a did for us 500,000 years ago that is no longer
01:57:58.440
beneficial in this lousy environment, the centenarians have managed to tap into its properties of-
01:58:05.440
So what we did, and it's all published in computational biology journals, we took every one of the
01:58:13.540
longevity gene that we have and we did gene-to-gene interaction.
01:58:19.900
In other words, we tried to see if there's interaction between the bad genotype and the
01:58:28.460
And we did it to a variety of those U-shape, right?
01:58:34.680
You know, it goes down with aging and then it's good in centenarians.
01:58:38.500
And we really found statistically significant that LP little A is protected by people who
01:58:47.620
are homozygous to a CTP mutation that is a longevity mutation that we found before.
01:58:55.920
In other words, most of the people with the LP little A that are centenarians were also
01:59:07.220
So I've talked on this podcast a lot about CTEP and its role in reverse cholesterol transport,
01:59:14.000
Talk to me about what does the lipid panel look like for someone who is CTP VV plus or minus
01:59:21.160
So those with CTP VV, they have higher HDL levels.
01:59:27.020
They have larger lipoprotein particle size and they have lower CTP levels.
01:59:37.240
And this CTP has been protective against several age-related disease.
01:59:43.880
And by the way, the two ApoE4 are also CTP VV carriers.
01:59:49.740
So really, the question is, it sounds to me like if you are a CTEP VV, that's a very
01:59:58.500
And the difference, if I remember the data going from 70 to 80, was basically flat.
02:00:03.520
If you're a CTEP VV, it really goes up when you turn 80.
02:00:12.400
Yes, the genotype goes up significantly once you hit 80.
02:00:27.540
First of all, the 8% that have VV, I don't know how many of them will be centenarians,
02:00:41.300
Because the problem with HDL cholesterol is it's just such a dumbass metric.
02:00:45.800
It's so far downstream that it doesn't tell us much.
02:00:49.040
But the hypothesis here would have to be that these people have far more functional HDL
02:00:55.300
Because, I mean, we don't have to rehash this, but anytime you pharmacologically increase HDL
02:01:01.240
cholesterol by inhibiting CTEP, nothing good seems to happen.
02:01:05.400
Because you're actually impairing the reverse cholesterol transport.
02:01:14.800
A functional thing of the HDL probably or the lipoprotein particle side or something else.
02:01:23.340
Why wouldn't the LP little a phenotype or the LPA gene flatline after 80?
02:01:31.600
In other words, I understand why CTEP VV is protective.
02:01:35.620
I don't understand why LP little a should concentrate.
02:01:38.520
I think because the CTP is common and is very protective.
02:01:51.500
But for a person who's born and is going to be a centenarian, for them, it's really not
02:02:09.600
You take 100 people who are going to be centenarians, 100 people who are not, 8% of each of them,
02:02:18.540
Okay, we should do the math on if it's, are we being fooled by the age?
02:02:23.520
Because I do have one alternative hypothesis, by the way.
02:02:33.920
Because the other hypothesis I've often wondered is, depending on, so I'll start with my question
02:02:45.400
Do you know how much heterogeneity is with their Kringle repeats, for example?
02:02:56.500
So the things that we've done are, though we can do, actually we've done a little bit
02:03:06.120
But those calculations are on gene-to-gene interaction, okay?
02:03:10.860
Taking out the people without genotype and without genotype and seeing who are the people,
02:03:16.600
who are the centenarians that stayed with the bed LPA genotype.
02:03:27.560
Yeah, and I have a proteomics done, and maybe we can have some measurement.
02:03:35.740
I wonder if there's a clue to a very vexing question, which is, why is it that some people
02:03:42.060
with high LP little a do not go on to get premature heart disease?
02:03:50.340
And it appears completely uncoupled from the level of their LP little a, which makes
02:03:56.400
me wonder, are there virulent and non-virulent phenotypes that at the level of expression
02:04:06.680
And my question then becomes, is the non-virulent one the one that is concentrating in the centenarians,
02:04:13.740
and are they the population in which we should understand that phenotype so we can better risk
02:04:19.280
stratify the rest of us schleps walking around today, 10% of whom have elevated LP little
02:04:24.920
a, but we don't know how aggressively to treat them.
02:04:27.340
Yeah, I didn't know that there's virulent or non-virulent LP little a.
02:04:31.040
My explanation is totally gene-to-gene interaction.
02:04:36.660
I guess the answer is, is different, is that the people with the, what's the LP little
02:04:47.880
And maybe you can see that's generalized that if you inhibit CTP, the LP little a is less
02:04:55.620
I mean, I think the problem we, I agree with what you're saying.
02:04:58.360
The challenge is we do not have an HDL functional assay.
02:05:01.280
So right now we can measure HDL cholesterol, we can measure HDL particle number, and we
02:05:05.680
can measure HDL size, but none of those come close to telling us how functional the particle
02:05:10.860
Well, I have a collaboration with Dan Rader, who's doing HDL efflux and stuff like that.
02:05:19.440
So maybe, but I'm, you know, that's not my, this is a past life for me.
02:05:30.720
Let's go back to the IGFGH thing, because this one still creates tremendous, let's bring
02:05:37.200
So I'm often asked by patients, Hey, should I be on growth hormone?
02:05:43.880
But if I'm going to be brutally honest, I really don't know.
02:05:47.080
I really have no insight into whether growth hormone is exogenous administered growth hormone
02:05:54.960
Because the clinical data certainly don't give us the answer, right?
02:05:58.260
So the epidemiology, if you're in sort of, you know, Valter's camp is, that would be
02:06:07.000
But again, the epidemiology tell a different story, tell a much more nuanced story that
02:06:11.520
has to do with how high is too high at what age and for what gender and with respect to
02:06:21.020
Well, you can manipulate it, the two easiest ways to manipulate IGF, the three easiest ways
02:06:25.440
to manipulate IGF are to manipulate growth hormone exogenously, manipulate IGF dietarily,
02:06:31.920
predominantly through amino acids, and manipulate insulin to indirectly impair or enhance IGF-binding
02:06:40.200
Well, let me tell you, we just published a paper in Nature a month ago, a study that
02:06:44.860
we're going also for a while, and what we did is we got from EmGen, EmGen, as much as
02:06:52.100
other pharmaceuticals, tried to develop antibodies against IGF receptor because IGF receptor is
02:06:59.240
Yeah, this was the disaster drug that they tested against metastatic pancreatic cancer.
02:07:05.460
But if I recall, there was a very special little gift, which is no CNS penetration.
02:07:15.460
So it failed, but we're interested for aging, right?
02:07:20.220
And not only we're interested for aging, our hypothesis was that IGF, you know, that you
02:07:26.520
need to decrease IGF action in the periphery, but increase it in the brain because of the
02:07:37.940
Murinize means to make it available for a mouse.
02:07:40.920
And we got it and we did a longevity study that we started at 22 months.
02:07:46.640
By the way, remind me in the human study, how much did it lower IGF in the periphery?
02:07:54.300
How much did it lower IGF activity in the periphery?
02:08:08.560
And they rebounded a little bit with IGF, which is not the case with aging because with
02:08:12.700
aging, you don't have the growth hormone secretion.
02:08:16.000
So we gave it to 22 months old animals that are 70, 75 years of age equivalent.
02:08:23.320
We increased their health spend dramatically and we increased their lifespan by 10% at an
02:08:39.920
You basically showed that you didn't change IGF levels in the brain or you actually increased
02:08:48.080
There is a little increase in IGF-1 level in the periphery.
02:08:52.020
And we're assuming that we didn't make it a big, I'm telling you what we thought.
02:08:57.460
We didn't make it such a big deal, but obviously the antibodies do not cross the blood brain
02:09:03.380
barrier, but the IGF wasn't lower if anything was high.
02:09:08.580
So if anything, IGF went up in the periphery because it was being blocked.
02:09:12.300
And therefore a little bit higher in the periphery.
02:09:14.140
So you could have had more CNS activity, less peripheral activity of IGF.
02:09:21.900
In males, we started to do the studies in males.
02:09:24.740
And since we didn't see any major effects and we had relatively little, you know, those
02:09:34.560
So we eventually did the longevity only in females.
02:09:37.720
We don't have data on males, but the extent of health span, and you'll see the paper.
02:09:43.160
It's really, it's a great paper with lots of studies.
02:09:46.420
And it's impressive how much they did better, the females with that.
02:09:53.240
We have all the paths where you ask, what do we do?
02:10:01.020
The only problem for us is aging could be an indication what's before aging.
02:10:07.020
Like we need another indication in order to start selling it before.
02:10:10.400
But what's your hypothesis in those mice, in the female mice, that they, you said they
02:10:20.820
They had a cardio, you know, they had the cardiovascular protection.
02:10:24.940
They have cognitive advantage, functional advantage.
02:10:29.380
The interesting thing between male and female, the difference is the mice, the female mice that
02:10:37.620
were treated with IGF receptor antibody had a lot of, of inflammatory markers, right?
02:10:47.700
And those inflammatory markers were really decreased with aging.
02:10:52.760
In males, we had a little bit more inflammatory markers, but they increased with the IGF treatment.
02:11:03.660
And both the males and the females had an increase in peripheral IGF.
02:11:07.520
Presumably the antibody was working in both of them.
02:11:09.840
But somehow the inflammatory response in males was different.
02:11:18.160
Here's a good example of a drug that was in females.
02:11:21.400
And we have preclinical proof of concept that it's good.
02:11:26.180
But the second is in males, all those have not been shown.
02:11:32.000
And in fact, you know, the functional that I told you functional in women, it looks like
02:11:37.320
the function was better for men with a higher IGF and not with lower, not statistically significant,
02:11:47.900
So I'm telling you from human studies, from genetic studies, I'm telling you growth hormone
02:11:56.280
It should be dangerous for elderly people, for elderly women.
02:12:00.920
With men, I'm ready to say that I'm not sure, you know, I'm not sure.
02:12:06.820
It's not that I've shown that low IGF or growth hormone is better in males, not in my rodent
02:12:16.520
But it's hard to say that giving growth hormone is bad when, you know, by the way, the growth
02:12:23.640
hormone receptor story is a lot of them are males.
02:12:30.120
I mean, this is such a layer of sophistication to this question, which I've largely sort of
02:12:35.980
decided that I can't come up with a compelling reason for exogenous growth hormone.
02:12:41.480
But I also can't see much evidence clinically that it's killing people.
02:12:45.460
But of course, I think disproportionately the data are in men.
02:12:48.720
What do you think explains this sex difference between men and women?
02:12:51.940
I think I'm really, if you look at this inflammatory panel, lots of cytokines in lots of animals,
02:12:59.280
I'm not sure, we don't have the intellectual link to say what happens, but this is something
02:13:08.820
Because if for some paradoxical way that is sex dependent, low IGF, increased inflammation,
02:13:18.160
we want to know why and we want to know how we can affect it.
02:13:24.220
It would be great if you could repeat the study with younger mice, both male and female again,
02:13:30.500
because, I mean, the most obvious example is the biggest difference between the men and
02:13:35.360
women and women are the sex hormones, and the older they get, that difference is still there.
02:13:40.920
I mean, women will, you know, the female mice would go from having some testosterone to zero
02:13:48.300
But, gosh, the men would probably still have more estrogen than the, the males have more
02:13:58.080
Which makes me wonder if the estrogen, the progesterone, and the testosterone are somehow
02:14:06.440
So there's a, you know, we're working on a grant, because the sex issue is so interesting,
02:14:14.360
we started working on there, lots of models where you can change X and Y chromosomes and stuff like
02:14:21.380
that, and, you know, we're looking at the way to look at the, because it's, I don't think it's
02:14:26.660
usually as simple as the sex hormones, you know, I think we're missing a whole biology,
02:14:33.160
a whole biology, and whatever is the sex hormones, I don't understand the inflammation in that either.
02:14:39.900
But by the way, your idea of doing it in young is good.
02:14:42.820
Mgen sold this IGF receptor and we cannot get, we cannot get more samples, but we're interested
02:14:51.200
Wait, wait, Mgen sold the rights to the human antibody.
02:15:00.900
To like a private company that we're unable to get people to, though I have to say it's
02:15:06.840
not our major priority now, but, and we have some consultants that are trying to get it
02:15:14.500
So, you know, it's still an issue, but I'll tell you, if I had to develop a treatment,
02:15:18.840
I would rather use the micro RNA 142 because the IGF receptor antibody didn't work in cancer,
02:15:28.420
but maybe the micro RNA penetrates better in another way.
02:15:32.800
And maybe that's the way to decrease IGF receptor in, you know, in cancers.
02:15:38.320
So anyhow, but I really answered you that, yeah, there are things that we could do to affect
02:15:44.680
I mean, what do you think about sort of all the, to me, the most obvious way to manipulate
02:15:49.220
So about once a quarter, I fast for a week with just water only, and it has a profound
02:15:57.380
So for my age, I think I should know these numbers off by heart, but plus or minus two
02:16:03.820
standard deviations of IGF at my age is about 90 to 250.
02:16:10.460
And if I take my, if I measure my IGF level before a fast, right before a fast, it might
02:16:30.840
So it sort of falls precipitously during the fast and then slowly rises and then falls
02:16:38.640
And there's part of me that just wonders if a cyclic approach to IGF is a healthier approach
02:16:44.560
than say, constitutively being calorically restricted and just, you know, because you
02:16:49.260
could starve yourself of methionine and eat no protein and live at a lower IGF level of
02:16:56.900
But I wonder if the real game is sort of figuring out this sort of cycle and periods of, just
02:17:02.360
as we think of autophagy, if you're always in a state of autophagy, that's a bad thing.
02:17:07.340
If you never have autophagy, that's a bad thing.
02:17:10.200
So you know about the calorie or the caloric restriction that the NIA funded in three centers?
02:17:17.040
Yeah, Eric Ravison at Pennington was one of the main PIs.
02:17:19.820
One of the things is that IGF level wasn't decreased in those people, right?
02:17:25.140
And we think IGF decrease is really an important part of longevity.
02:17:33.200
And maybe I'm digressing because I'm sure you talked about it more, that what we're doing
02:17:40.840
We're doing intermittent fasting because in our rodents, we would bring the food in the
02:17:46.280
morning, they were hungry, they would eat all the food, you know, the 60%, whatever we
02:17:52.980
gave to it, Libidon, and they were fasting for 23 hours.
02:18:02.700
But in Eric Ravison's studies, they didn't have low IGF because it wasn't caloric restriction
02:18:07.760
They gave them just less food throughout the day.
02:18:10.420
And I think that was a big mistake that we realized we were doing.
02:18:16.640
I think what we're trying to do at Einstein is we're doing a study.
02:18:22.040
We know that autophagy is improved quite fast in fasting rodents.
02:18:35.780
And by the way, we can do with Anna Maria Cuervo, we can take T lymphocytes and look at the
02:18:44.260
And they actually reflect also autophagy in the brain.
02:18:49.280
What are you looking at specifically in the assay?
02:18:51.800
Well, there are several things because there are several autophagies, right?
02:18:55.980
So macro autophagy or chaperone mediated autophagy.
02:19:09.760
You know, like for example, if a rodent is fasting for 24 hours, especially a mouse,
02:19:17.480
I mean, that's, gosh, that's probably the equivalent of a human fasting for a week.
02:19:22.140
Presumably autophagy is highly, highly, highly upregulated.
02:19:25.620
If you give the mouse a little bit of chow and then measure that assay, does it obfuscate,
02:19:32.240
does it erase the fact that they've been, does it create the illusion, I guess I should
02:19:36.420
say, that it's erased, that they've had this high period of autophagy?
02:19:42.020
You know, Anna Maria Cuervo did, and I don't know the answer.
02:19:47.760
And, but the important thing is to find the time course in humans so that we can really
02:19:53.160
say, for example, what I'm doing basically is I'm trying not to eat after dinner until
02:20:02.640
But do you really, I mean, so first of all, how hard is it to get an IRB at Einstein to
02:20:06.740
No, no, no, we have IRB, we just wrote a grand, we need money for that.
02:20:12.000
Yeah, I guess, you know, I have a whole framework around nutrition, which I'm happy to kind
02:20:15.640
of walk through as we inhale our dinner tonight.
02:20:18.900
Have you decided, by the way, if you want Indian, Turkish, Persian, Greek, all of the
02:20:27.100
You know, because it's raining out, so I guess one of the things we could do to the closest.
02:20:33.380
So my concern with time-restricted feeding, which I practice quite liberally, is I'm worried
02:20:39.760
it is not a significant enough deprivation of nutrients in humans.
02:20:44.360
In other words, I think Sachin's data is so impressive in mice, you know, but I think that
02:20:50.420
for a mouse to go 16 hours without eating is an enormous task.
02:20:55.160
It might be the equivalent of us not eating for three days.
02:20:57.820
And now that said, I'm struggling to see a downside of time-restricted feeding.
02:21:03.340
And I know that, you know, Valter and others have said time-restricted feeding is somehow
02:21:10.900
But this is a very interesting question you're asking.
02:21:13.460
I would argue it's the most interesting question of all.
02:21:15.700
Because if we understand the time course of that, all of a sudden we can program nutrient
02:21:24.060
And have you looked at that assay in the presence of rapamycin or metformin?
02:21:30.140
But metformin, Ana Maria Cuervo is using metformin as the control for autophagy.
02:21:40.240
So that's what I'm talking about in vitro assays.
02:21:47.800
The one thing I should say, I just don't want to forget anything.
02:21:55.680
It just reminded me, it's back to the metformin studies.
02:21:58.200
So our reviewers were saying, you know, okay, all the data on the biology that you showed
02:22:07.780
And we don't know that the biology is relevant to humans.
02:22:12.440
Although, of course, the preliminary data in humans are much better than in rodents, right?
02:22:19.220
So we had a clinical study, a small clinical study, which we took 15 people that are 75
02:22:26.720
years old, and we gave some of them metformin for six weeks and other placebos, and then
02:22:36.980
And we took it at the end of each period, we took biopsy from their muscle and biopsy from
02:22:46.940
And we looked at the transcript and the metabolomics, but mainly the transcripts in the tissues to
02:22:59.560
First of all, when they brought me their clinical results, you know, insulin, HOMA, glucose, and
02:23:06.520
all, there were significant effects in many of them, statistically significant effects,
02:23:15.840
And then we found out that the people who were last on metformin, although it was half of
02:23:21.960
the people, had much more significant results than the whole 15 people.
02:23:29.800
The people in the crossover who started, who went placebo to metformin.
02:23:48.620
And the reason is that probably the two weeks washover is not enough.
02:23:58.700
Okay, so if you got metformin and then placebo, you didn't really, you went halfway back.
02:24:06.760
Also, by the way, because metformin is associated with weight loss and they lost a little weight,
02:24:11.380
that on itself really made them on the second part.
02:24:17.860
What do you think explains the weight loss phenotype of metformin?
02:24:22.020
So when I started taking metformin, which was 2010, I didn't mess around.
02:24:33.360
I mean, I took 2,500 milligrams first thing every morning.
02:24:37.960
And after a month, I lost quite a bit of weight.
02:24:43.280
I mean, the thought of eating was repulsive to me.
02:24:47.320
You know, I was exercising a lot and doing all my usual shenanigans.
02:24:50.380
But I clearly ate less just because of that low-grade feeling of nausea.
02:25:07.980
And I see far less of that nausea, and I see far less weight loss.
02:25:13.200
What other mechanisms do you think it could explain the weight loss?
02:25:19.060
You know, just like ketones, you get a little bit-
02:25:21.340
An additional substrate, an additional substrate.
02:25:24.080
But look, I started metformin several years ago because I was pre-diabetic.
02:25:36.000
And I was just surprised after three months to realize that I lost, you know,
02:26:00.260
And I probably didn't eat as much, totally not noticing it.
02:26:08.340
I tell patients not to expect that because I don't like the idea of patients thinking
02:26:14.080
To me, that sort of is not the right way to think about it.
02:26:18.660
And by the same token, I have had, I should be clear, I've had also some patients who
02:26:23.140
have, they've come back and they've lost 10 pounds.
02:26:27.120
This is not, you know, this is someone that by everybody's standard would be completely
02:26:32.620
You know, BMI is 24, body composition is reasonable, and comes back in, you know, in
02:26:40.180
But I guess for in my, at least in my practice, that seems to be the exception and not the rule.
02:26:46.820
You know, I guess, of course, you wish that was more than a two by two, two week.
02:26:55.260
And we're doing longer study with longer washing period because we want to get away from
02:27:00.220
But back to metformin, I said that's one thing is this metformin last issue.
02:27:05.440
The second thing that we showed that most of the transcript changes were relative to
02:27:11.800
You know, in fat, it was more free fatty acid metabolism and the muscle was more pyruvate
02:27:18.660
In other words, there wasn't the metformin, you know, the metformin part.
02:27:23.180
But in both tissues, there were genes that are not metabolic genes, you know, like BRCA1 or
02:27:30.880
myofibril genes and other things that are related to aging, but they are not metabolic.
02:27:38.860
In other words, the concept that metformin is not only metabolic, it's aging, okay?
02:27:46.060
You know, some other gene, genes that are associated with DNA repair changed significantly.
02:27:55.760
Did you see in the muscle, by the way, if you still have biopsies, I'd be very curious to
02:28:00.320
know if the lactate transporter out of the muscle, I'm blanking on it, it's MCT2.
02:28:07.920
In other words, as people make more and more lactate in the muscle, do they get more and
02:28:12.240
more efficient at shuttling it back to the liver?
02:28:23.080
It didn't come up, I'll tell you, it didn't come up as a winner, but that doesn't mean it's
02:28:28.340
And you looked at genome or you looked at messenger as well?
02:28:38.100
Well, if it was highly, I mean, there are hundreds of changes, okay?
02:28:43.560
Yeah, maybe this was underpowered to see that difference.
02:28:47.140
So I can still answer you, I can still answer you specifically.
02:28:55.000
You know, if I take that and see that it can be, without taking into account that there
02:29:04.080
The other thing, though, what you do with transcript, you look at upper regulators of the system,
02:29:14.220
So if you look at the upper regulators, you get back to the same things that are affecting aging.
02:29:20.500
AMP kinase, mTOR, all those pathways were affected by metformin, except that what you measured below is the tissue-specific effects.
02:29:36.660
And so we really connected not only the clinical data, but the biological data in humans to the TAMES study.
02:29:46.540
You know, a few years ago when my father was diagnosed with cancer, I immediately put him on metformin.
02:29:54.100
And, you know, in his infinite wisdom, his primary care doctor took him off it because, you know, why would you put him on metformin?
02:30:01.820
And in the end, my father decided his primary care doctor knows much more than I do, and so remains off metformin.
02:30:09.300
But certainly this discussion, because I, you know, I probably know more about metformin than the average person,
02:30:15.040
but this discussion has been completely illuminating.
02:30:17.560
There's one other thing I want to ask you about, which is all of the discussion around NAD.
02:30:24.260
What is your take right now based on the state of the science that we have,
02:30:28.560
which admittedly I think we're just scratching the surface of, as far as first and foremost,
02:30:35.000
just at the mechanistic level, what is your belief that orally administered nicotinamide riboside
02:30:43.520
I don't know if you've seen it, but Josh Rabinowitz's paper over the summer would suggest,
02:30:48.880
So wouldn't this sort of call into question the companies, there's two of them right now,
02:30:54.940
Chromadex and Elysium, that sell basically nicotinamide riboside plus or minus terastilbene.
02:31:03.620
What do you think explains the reported efficacy of those agents in light of Rabinowitz's NAD tracer study?
02:31:10.480
First of all, the Rabinowitz study was also criticized, okay?
02:31:16.640
Time course and other things, which, okay, I'm just saying that.
02:31:22.320
But I think really the biggest issue here, I want just to use this opportunity to say
02:31:28.680
that a lot of what we're doing is not based on clinical studies, okay?
02:31:35.700
And it really just underlines the fact that unless you do a clinical study, you can remain guessing.
02:31:45.840
Now, I'll tell you, I'm taking a good preparation of NMN, okay?
02:31:51.340
Tell the listener the difference between NR and NMN, because they're both precursors to NAD,
02:32:05.920
Okay, but in theory, one is slightly more stable than the other.
02:32:08.440
Right, it's a stability issue, availability issue, but they'll fight.
02:32:12.460
And we don't know which is the better, and we don't know which gets to the tissue, right?
02:32:29.160
You say that as you hold up a bottle of Topo Chico.
02:32:35.060
Okay, but what I'm doing now is I'm opening my Fitbit, okay?
02:32:39.960
And one of the things that the Fitbit has is sleep, okay?
02:32:46.660
No, I use something called Aura, which works much better.
02:32:51.740
Do you get also the deep sleep and the REM and all that?
02:32:56.120
Since I started taking NMN, and it might be a coincidence, so I have to stop it and start again, but my sleep has been much better.
02:33:08.100
That means I have, in the beginning of the night, I have much more deep sleep, and at the end of the night, I have much more REM.
02:33:14.400
And I thought, if there's anything I can say about it, is that just because of this association, okay?
02:33:32.940
Do you take the NMN by itself, or do you also pair it with terastilbene or another sirtuin activator?
02:33:49.280
He's from St. Louis, and he has his own patents and studies in Japan on NMN.
02:33:58.040
And he tells me, unprovoked, he says, you know, I have 200 subjects, and one of the interesting things is their sleep patterns improve.
02:34:06.580
They get more deep sleep in the beginning of the night and more REM at the end of the night.
02:34:10.900
In other words, he tells me what I've noticed, and it makes me just think and maybe believe and maybe hope that something is getting into the cells and that there's a real effect, at least on sleep.
02:34:31.380
But really, my answer is, we don't really know enough.
02:34:36.600
It's very hard to measure effect because this NAD goes and goes away.
02:34:46.800
And without clinical studies that are really well controlled, I think it's going to be hard to just support that.
02:34:59.000
And that's me as a conservative scientist and one who says that even metformin, that everybody says, you have enough data.
02:35:06.900
No, we have to do the clinical study to prove that.
02:35:11.380
And it seems to me that intravenous administration of NAD is also not particularly helpful, though it seems quite popular in the sense that I haven't seen compelling evidence that giving NAD intravenously makes its way into the cell either.
02:35:29.220
So I think the development, the interesting development will be to develop a drug and the drug will be a precursor that will get into the blood.
02:35:44.520
So if you could give NR or NMN sublingually or intravenously, that strikes me as very interesting.
02:35:51.640
Saying that there's a lot of data in rodents where also you look, you give it in different ways.
02:35:59.560
You give it some in water, but some are gavage.
02:36:02.560
And maybe that's different because one of the problems, maybe if you go deep enough.
02:36:11.120
So, you know, but the in vivo studies are good studies.
02:36:22.860
There's a lot more I want to sort of pick your brain on, but we could also just sit down and do this again sometime.
02:36:29.260
I want to make sure you've said at least as much as you want to say about metformin.
02:36:33.100
Because I think that to me is, you know, you're at this point arguably one of the world's experts on a drug that, just to put this in perspective,
02:36:41.020
I think Lou Cantley, who is obviously a close mutual friend of ours, and James Watson, who I don't know personally,
02:36:47.960
have both said quite publicly that metformin may have already saved more patients' lives from cancer than all other cancer drugs combined,
02:36:59.340
This is a drug that I think with each passing day, more and more people are beginning to learn about, beginning to ask questions about.
02:37:07.740
And my hope is that if nothing else, this podcast is a place that people can listen to this episode if they can't go and read 16 of your papers.
02:37:16.640
And they don't necessarily want to get, you know, that far down the rabbit hole.
02:37:20.940
But to hear it from you and not from me or some other schmuck who doesn't know much,
02:37:25.920
I want to make sure that if there's anything else you want to say about metformin that you say so.
02:37:30.600
And so is there anything else that you want to add?
02:37:32.340
Well, let me do one practical thing and one a little bit more philosophical, okay?
02:37:37.980
The practical thing that really surprised me, I was giving a talk somewhere for lay people.
02:37:45.420
So it was organized by a university and they invited people and to their surprise, there were 300 people in the audience.
02:37:54.860
And by the way, my talk wasn't about metformin.
02:37:57.980
My talk, the titles of my talk is usually how to die young in a very old age.
02:38:03.760
That's what my title is usually, if I can get away with it, that's a good title.
02:38:09.360
So people are coming and as they're entering, some of them come to me and say, so how much metformin should I take?
02:38:15.720
Okay, so I started talking and all of a sudden I said, let me ask you something.
02:38:21.520
Who here in the audience is non-diabetic and is on metformin?
02:38:29.000
And please, you know, you don't have to, just if you choose to.
02:38:43.780
So, you know, in other words, the prophecy is out, which makes me a little bit worried about the study.
02:38:53.020
When we first, Wall Street Journal is the first that picked on Tame, wrote an article, the next week we had 3,000 phone calls and emails of people volunteering to the study, which is what we need to do the study.
02:39:09.860
But just cut your, you trim that budget from 70 million down to 65, you cut all the recruiting costs out.
02:39:19.540
Then you realize, just a minute, those people, first of all, we didn't advertise.
02:39:25.820
And second, they'll do, they're doing other things.
02:39:30.660
You know, it's like with the estrogen bias, they're probably exercising and stuff like that.
02:39:34.480
And then when I started getting emails, like I'm volunteering to the study as long as I'm not on the placebo, I thought, you know, if people care so much, if they'll figure out they're not on metformin, they'll just get metformin.
02:39:49.460
So from recruiting the 3,000, we, we outload those, those are not in my study, right?
02:39:58.560
So I want to say that still, we haven't done the study.
02:40:10.760
We don't know if it's safe as it is in young people.
02:40:13.740
And so we don't have really a clinical study with evidence that this is good.
02:40:20.940
And I'm, I'm just worried now that part of the reason to do this study is because if it's not good, people should know also, right?
02:40:37.160
So I said before that I was invited to the Vatican.
02:40:43.060
And I'm, I'm very close to Cardinal Ravassi, who's a number four in the pontiffs.
02:40:50.840
He's, he's in charge of science and on arts that is including science.
02:40:55.560
And it's interesting because the Vatican basically says, we don't want to be in a Galileo Galilei situation again.
02:41:03.160
We don't want to be in a situation where the science is so right and we're so wrong that we don't know what to do with it.
02:41:09.440
And so they called me and they said, you know, we have a meeting in the Vatican.
02:41:20.200
And then I'm going on and saying, am I, am I the keynote speaker?
02:41:23.480
And they said, the keynote speakers are the Pope and Joe Biden, who was vice president.
02:41:36.880
Joe Biden goes up and explains his cancer initiative and how difficult it is.
02:41:43.000
Because when you have cancer, you have in the cancer, maybe five other genomes.
02:41:48.120
And they're also different than every other cancer like that in the world.
02:41:53.960
Then comes the Pope and says, you know, I still hope that there'll be one little pill cheap for everyone in the world that will cure whatever cancer they wear.
02:42:10.780
But then I go up and I say, well, there is actually a cheap pill like that.
02:42:18.340
And I don't know if it cures any cancer in the world, but it can prevent a lot of the cancers in the world.
02:42:24.860
And actually, it has a side effect that it also can prevent a lot of other diseases in the world.
02:42:30.300
So it was like, you know, going back to aging and the risk of aging for age-related diseases and how impactful and cheap it could be compared to treating cancer or something like that.
02:42:48.900
So I think the prevention of aging is really a good place to be.
02:42:54.600
And I think because we went from hope to promise and we have to realize the promise, I think life is going to be very different in the next decade with our advance.
02:43:04.700
Last question, and not to end on a downer, but let's try to figure out where a blind spot could be.
02:43:13.580
Obviously, you and I share more in common in terms of philosophy and points of view than I even realized before we spoke.
02:43:22.960
So, you know, I'll tell you what's my optimism.
02:43:27.580
You know, we have, the European have nine pillars of aging and we have seven pillars of aging and they're all interconnected.
02:43:38.180
And when I say interconnected, I just spent the time with Anna Maria Cuervo this morning.
02:43:44.220
When she fixed autophagy, she fixes also metabolism.
02:43:50.980
Okay, there, when you start doing things in any one of those pillars, you start improving the others.
02:44:01.680
Now, where we could be wrong is we don't know what is the impact of each of those pathway in humans.
02:44:13.900
But I think our fallback is that we all age, the advantage of in aging is that aging is universal.
02:44:27.440
Every animal has the skin, the hair, the skeletal, the frailty.
02:44:41.380
You give it to any animal, it almost delays the aging there.
02:44:48.820
I think that maybe some pathways will not be so effective.
02:44:56.200
But I think we have to affect three, four, and we're right on our way to do better.
02:45:04.380
And in the TAME study, will it be one-to-one, male-to-female?
02:45:10.760
And have you powered it such that men and women are different animals?
02:45:13.740
Well, no, because all our data on metformin, and we looked carefully to the DPP and other,
02:45:19.660
they didn't see any gender effects on any of the outcomes.
02:45:24.620
So you're powered as though the genders don't have a significant...
02:45:40.620
But then when I woke up this morning, I was like, there is no way we are postponing this
02:45:44.740
discussion because I cannot wait to have this discussion.
02:45:51.680
It was, you know, it was great because you asked really great questions.
02:45:56.580
And also, I'm now quite hungry and I'll be happy to have dinner with you now.
02:46:01.300
Oh, we are going to put together a seminar on how not to calorically restrict.
02:46:10.540
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02:46:18.260
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02:46:22.380
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02:46:28.480
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02:46:31.360
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02:46:49.560
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