Pod Insights StarTalk Podcast Do We Have to Die? with Venki Ramakrishnan About this episode Why do we die? Do we have to? Neil deGrasse Tyson, Chuck Nice, and Gary O’Reilly explore the paradox of death, the science of aging, and the search for immortality with Nobel Prize-winning structural biologist Venki Ramakrishnan.
Transcript 10,238 words · 5 speakers
Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:00 Neil deGrasse Tyson? Why are you bombing us out with a topic on why we die?
0:02 Gary O'Reilly? Because we have a Nobel Prize winner as our guest.
0:05 Neil deGrasse Tyson? Dude, we have a comedian, it's a happy show.
0:07 Chuck Nice? It is a happy show because we're not talking about me dying on stage for once.
0:13 Neil deGrasse Tyson? Coming up on StarTalk, how and why we die.
0:19 Neil deGrasse Tyson? Welcome to StarTalk, your place in the universe where science and pop culture collide.
0:28 Neil deGrasse Tyson? StarTalk begins right now.
0:32 Neil deGrasse Tyson? This is StarTalk. Neil deGrasse Tyson, your personal astrophysicist, this is special edition, which means we've got Gary O'Reilly. Gary?
0:41 Gary O'Reilly? I'm Neil.
0:42 Chuck Nice? Hey. And we got Chuck Nice.
0:44 Neil deGrasse Tyson? Hey, hey. Okay. What's happening? And special edition specializes in all science that matters to the human condition.
0:52 Gary O'Reilly? Yes.
0:52 Neil deGrasse Tyson? And today's topic is no exception.
0:56 Gary O'Reilly? No.
0:56 Neil deGrasse Tyson? And I, may I give the title of it?
1:00 Gary O'Reilly? Please do.
1:00 Neil deGrasse Tyson? Why we die. Dun dun dun.
1:06 Neil deGrasse Tyson? Why we die. Well, I have no expertise in that other than simply being alive. Right.
1:14 Neil deGrasse Tyson? But I fear death because I'm born knowing only life. Wow, look at that. Yeah. I got that from a movie. Oh, okay.
1:22 Gary O'Reilly? That's okay. So, Lane and I are co-producer on this.
1:26 Neil deGrasse Tyson? Lane Unsworth, our LA producer for StarTalk, yes.
1:29 Gary O'Reilly? We have long wanted to investigate this subject matter.
1:33 Chuck Nice? You want to investigate it, but not firsthand?
1:35 Gary O'Reilly? No.
1:38 Gary O'Reilly? More an observation, more an observation. So if you put it this way, humankind has for millennia asked, why do we die? Followed by, well, why can't we live forever then? And then?
1:50 Neil deGrasse Tyson? It's kind of the same question.
1:51 Gary O'Reilly? Yeah, but, you know, different people. So has evolution programmed us to expire on a certain date? Could we extend the game? Cheat death, play god, if you wish. Millions, if not billions, are spent annually on anti-aging, be it research or products.
2:07 Neil deGrasse Tyson? Millions of dollars.
2:09 Gary O'Reilly? Yes. And so how close are we to unlocking? The mystery of death. So no surprise that the research into proteins is proving to be the key to this mystery.
2:22 Neil deGrasse Tyson? So the building blocks of life may hold the key to death?
2:25 Gary O'Reilly? How about that?
2:26 Neil deGrasse Tyson? Oh, good sentence there. Very good, Chuck. So we have the world's expert on this very subject. Wow. And this is Venky Ramakrishnan. Venky, welcome to Stark Talk.
2:37 Speaker 03 Thank you.
2:37 Neil deGrasse Tyson? Excellent. And you are now based in Cambridge?
2:41 Speaker 03 Yes, England. Say it.
2:44 Neil deGrasse Tyson? I knew, I knew you had to fix that.
2:47 Speaker 03 Wasn't really necessary. It's always basher Brit day here.
2:52 Neil deGrasse Tyson? Yeah, yeah, it is, it is. But we do it lovably.
2:55 Speaker 03 We do, yeah.
2:56 Neil deGrasse Tyson? So you run a small group, but it used to be bigger because you're winding down in your career. A program leader at the M R C?
3:06 Speaker 03 That stands for Medical Research Council.
3:08 Neil deGrasse Tyson? Lab at Cambridge? Yes, and it specializes in bio?
3:13 Speaker 03 Molecular biology.
3:14 Neil deGrasse Tyson? Molecular biology.
3:15 Speaker 03 So it's the M R C lab of molecular biology.
3:17 Neil deGrasse Tyson? Okay, okay. Our name is what we do. But that's like the least of your resume here. So in 2009, you were awarded the Chemistry Nobel Prize. Wow. Why? Are you wearing it under your shirt right now?
3:34 Speaker 03 No.
3:36 Neil deGrasse Tyson? Because that's serious bling, you know? Honestly. You go to the club. Yeah, I would be like the Flavor Flav of Nobel Prize winners. I would never take it off. So a former president of the Royal Society, very important. That's a deal. Organization that basically the first, we think the first in the world to organize the ideas and publications of scientists. Wow. To make it a clearinghouse of peer review.
3:59 Speaker 03 First peer reviewed papers. Also advocated evidence-based science in the 17th century at a time when authority mattered a lot. And they said, authority doesn't matter. Beauty doesn't matter. It's evidence that matters.
4:14 Neil deGrasse Tyson? Very enlightened and important posture. And then you got knighted in 2012. That's three years later. And you, do they knight with an actual sword?
4:27 Speaker 03 Yes, but it's, I think it's blunt.
4:30 Neil deGrasse Tyson? Well, let's just hope. You don't want for the slip up. Right. If there's a little sort of jiggle in the wrist. We wanted to make him a knight, it turned into an execution.
4:43 Gary O'Reilly? Who was on the other end of the sword?
4:45 Neil deGrasse Tyson? Yes.
4:46 Speaker 03 Uh, it was Princess Anne.
4:49 Gary O'Reilly? Oh, cool.
4:49 Neil deGrasse Tyson? Cool. We like it. We love Princess Anne. Yeah.
4:52 Gary O'Reilly? That'll work.
4:52 Neil deGrasse Tyson? Yeah, yeah. Also, you have a book. Um, it's your second book. First one a few years back, The Gene Machine. But what we're especially interested in now is Why We Die. And give me the subtitle of that book, Why We Die.
5:06 Speaker 03 It's called The New Science of Aging and the Quest for Immortality.
5:11 Neil deGrasse Tyson? Well, let's dive right in because you are our world's expert in this. And before we can define death, I guess we should kind of define life and then learn what it is that ceases in life that then brings death upon it.
5:27 Speaker 03 Well, defining life is very hard. It's, you know, you could almost say, quote, Justice Potter Stewart, as, "I can't define it, but I know what I see."
5:38 Neil deGrasse Tyson? Spoken, maybe you don't know. Pornography. Because that's America. He said that of pornography.
5:43 Speaker 03 But the fact is, um, life, most biologists would define it as a system that can self-replicate and evolve. And at least in our world, it's carbon-based. But when we talk about death, it's a little complicated because there are many different kinds of death.
6:04 Neil deGrasse Tyson? Oh.
6:05 Speaker 03 You can have societies dying, cities dying, nations dying. Um, you can have companies dying. But what we're talking about is the death of the individual, which has a-
6:18 Neil deGrasse Tyson? The organism.
6:19 Speaker 03 Of an individual animal or organism.
6:23 Speaker 03 And there's a peculiar paradox there because while you're alive, I mean, right now, millions of cells in your dying, you don't even notice that, okay? That's cell death.
6:34 Neil deGrasse Tyson? Why you gotta tell me that right now?
6:36 Speaker 03 No, they need to die in order to, in order to keep you alive.
6:42 Chuck Nice? Oh, look at that.
6:43 Neil deGrasse Tyson? That's how he got out of that.
6:44 Chuck Nice? Thank you, dead cells.
6:46 Speaker 03 So.
6:46 Neil deGrasse Tyson? To make room for the new cells.
6:48 Speaker 03 To make new room for new cells, actually during development, cells will die at precise points as during development. They've done their bit and then they have to get out of the way.
6:57 Neil deGrasse Tyson? When you say development, mean embryonic?
6:59 Speaker 03 Embryonic development, correct. At the same time, when you die, when you say a person has died, at the point of death, most of you is still alive. That's why you can donate organs.
7:10 Chuck Nice? Right.
7:10 Speaker 03 Okay?
7:11 Gary O'Reilly? So there's the other side of the paradox.
7:13 Neil deGrasse Tyson? Interesting.
7:14 Speaker 03 So, what do we mean by death? Okay? You're gonna have, by the way, since you're an astrophysicist, you're gonna have death of the universe as well, and there's a book coming out on that, or has come out. So, the question is, what do we mean when an individual dies? What we mean is the irreversible loss of that individual's ability to function as a coherent whole. So that means that person can no longer exist as a, as a unit. And that's what we mean by death.
7:44 Chuck Nice? And are you talking physiologically, this person cannot function as a unit? Because there are people who experience brain death, or to an extent, and they keep them on a respirator because a family member says, "I don't want them to die."
8:01 Neil deGrasse Tyson? So there are two examples coming out of Chuck's point. You can be brain dead, but sustained on a respirator, so all your organs are working. And, or, you can be body dead, I suppose, and in the limit, it's like your brain in a jar. Whatever.
8:17 Gary O'Reilly? It can't, it can't happen. But that's more like a pontio presi.
8:20 Speaker 03 That can't, what you said can't happen, because if your body's dead, then it can't feed nutrients to the brain to keep it alive. The brain is the biggest consumer of.
8:29 Neil deGrasse Tyson? Resources.
8:30 Speaker 03 Resources. So, coming back to your point, though, about brain death, that's interesting, because... It used to be that if your heart stopped beating, that was the moment people said you're dead.
8:42 Chuck Nice? Right, right.
8:42 Speaker 03 Then they found out that actually, even if your heart stops beating, they can resuscitate you.
8:46 Chuck Nice? Right.
8:47 Speaker 03 But then they decided, okay, when you no longer have brainwaves and your brain has irreversibly stopped, that's brain death. And that's an interesting case. States in the US used to have different definitions of death. And there was a case where somebody died in California, but her relatives wouldn't accept it. And by New Jersey laws, she was not dead. So they moved the body to New Jersey.
9:13 Chuck Nice? Oh, wow.
9:13 Speaker 03 And she was maintained, as you say, on some sort of artificial device. And then eventually, she died. But this is slightly getting semantic because most people agree that there's a point when the body cannot reverse itself and get back to being alive.
9:33 Neil deGrasse Tyson? Yeah, but that's a statement of the limits of medicine in the day.
9:36 Speaker 03 Today.
9:36 Neil deGrasse Tyson? Right. So I remember, I mean, I read this, that one of the definitions of death is if you do not fog a mirror held up to your mouth.
9:45 Speaker 03 Yeah.
9:46 Neil deGrasse Tyson? And I'm thinking-
9:47 Speaker 03 That's respiratory.
9:48 Chuck Nice? Yeah, that was a long time.
9:49 Neil deGrasse Tyson? I'm thinking, you know, I'm glad that's not when I'm alive. I mean, I'm just thinking, thank you for-
9:55 Chuck Nice? Right, thanks for not being alive back then. Because I'm a light sleeper.
9:59 Neil deGrasse Tyson? Okay, so that tells me that however real our current definitions feel about when someone dies could be modified in the near or distant future.
10:09 Speaker 03 Absolutely. And neither birth nor death are very clearly defined. And I've pointed this out, that they're both somewhat fuzzy. I mean, when is it that you actually are you at birth? And that's the whole argument about abortion and all of that is just about that. And similarly, the point of death is also a little fuzzy.
10:34 Chuck Nice? When you're no longer you.
10:34 Speaker 03 Yeah.
10:34 Chuck Nice? Yeah, that's wild, yeah.
10:37 Gary O'Reilly? So the bit in between is aging.
10:38 Speaker 03 The bit in between is aging. And unfortunately for us-
10:41 Neil deGrasse Tyson? The little bit in between. Your whole life.
10:44 Gary O'Reilly? I may have downplayed that.
10:45 Neil deGrasse Tyson? Okay.
10:45 Speaker 03 And in fact, you start aging even in utero.
10:49 Gary O'Reilly? Interesting.
10:49 Speaker 03 From the time you're conceived, you know, your fertilized egg starts to develop.
10:54 Chuck Nice? Is that why all children are born looking like old men?
10:58 Neil deGrasse Tyson? Winston Churchill. So that's even earlier than a loaf of bread. Cause you know when a loaf of bread starts aging? No. Right when you take it out of the oven. Exactly. Okay. In that moment, it starts getting old. Right. Right, but here.
11:12 Speaker 03 This is in the oven.
11:13 Neil deGrasse Tyson? In the oven, you're getting old. Look at that.
11:25 Speaker 04 Hey, this is Kevin the Sommelier and I support StarTalk on Patreon. You're listening to StarTalk with Neil deGrasse Tyson.
11:39 Neil deGrasse Tyson? Forgive me as an astrophysicist, I hear talk of cells and, and, but then I also hear talk of proteins. So could you distinguish the two of them for me with regard to the role of aging?
11:51 Speaker 03 So aging is, you can think of aging as an accumulation of damage and changes to our molecules, our cells, our tissue and entire organs and the body. And this aging occurs at every one of those levels. So if you think of the molecule that holds all the information necessary to make all of the other molecules in the cell, that's our genes, our DNA. So DNA can be damaged. It can also change, which is not exactly damaged, but it can be modified as we age, typically by adding chemical groups to it, often methyl groups.
12:33 Neil deGrasse Tyson? It's gene editing.
12:35 Speaker 03 It's, uh, it's epigenetics. It's not editing as such. It's not changing the bases. It's not changing the letters of the DNA.
12:44 Neil deGrasse Tyson? That would be gene editing.
12:45 Speaker 03 That would be gene editing.
12:46 Neil deGrasse Tyson? Okay.
12:47 Speaker 03 This is epigenetics, which means sort of on top of, of genetics.
12:52 Neil deGrasse Tyson? Like the epicenter of an earthquake is the point on our surface above where the.
12:57 Speaker 03 Right.
12:57 Neil deGrasse Tyson? Yeah.
12:57 Speaker 03 And so you can, you can modify DNA and that changes. The way in which the program is expressed. So which genes are translated into protein.
13:10 Neil deGrasse Tyson? So this is the playing god part because now you are changing the.
13:15 Speaker 03 No, we're not doing anything. This is happening. This is happening even in utero.
13:20 Chuck Nice? Experiential circumstances can change your epigenetics. Is this the translation control of proteins?
13:26 Speaker 03 It's just part of life and it evolved for probably a very good reason. Mainly, it may have been of a cancer prevention mechanism early in life. We can get into why we have death from an evolutionary point of view. But nevertheless, the DNA program itself ages. You know, damage and modifications change the nature of the genes that you're expressing. Then that results in the proteins which are encoded by DNA.
13:58 Neil deGrasse Tyson? There you go.
13:59 Speaker 03 These are the workhorses of the cell. They carry out all the function. They give out, they give the cell its structure. Almost everything you think of as a property of life, like vision or touch or, you know, or antibodies, they're all proteins and they're all encoded by DNA. But as we get older, the quality of the proteins deteriorates. They're not made at the right time and the right amount. They start aggregating. You know, Alzheimer's is a case where proteins clump up together and form tangles.
14:32 Neil deGrasse Tyson? In the brain.
14:32 Speaker 03 So that also, yeah, in the brain. So that also is a consequence of age. And as a result, things in the cell, larger entities like compartments in the cell, also start to age. One of them are mitochondria, which are, mitochondria were actually bacteria that were swallowed up by a larger cell two billion years ago and then lived in symbiosis. And now, today, mitochondria are specialized as the centers for energy metabolism. It's where oxygen is used to burn sugar effectively and get energy out of it.
15:12 Neil deGrasse Tyson? So it's that kind of chemistry going that far back that accounts for our genetic similarity to life forms that are nothing like us? Like the, you know, we're something like 25% identical genes to a banana?
15:26 Speaker 03 Yes, yes. All eukaryotes came out of that.
15:29 Neil deGrasse Tyson? Yes.
15:30 Speaker 03 Out of that symbiosis.
15:31 Neil deGrasse Tyson? Okay.
15:32 Speaker 03 And so, so you can think of this as an ancient, you know, organelle that's now specialized. And because it's a center for oxygen usage, it can create what are called free radicals or reactive oxygen species, because these are partially reduced oxygen atoms which are chemically very reactive. So there's, you can have a lot of damage.
15:58 Neil deGrasse Tyson? To be clear, if it's fully reduced, that means all the oxygen is where
16:01 Speaker 03 It becomes water.
16:02 Neil deGrasse Tyson? And then you can't, there's nothing else that can
16:04 Speaker 03 Carbon dioxide and water is what you get.
16:06 Neil deGrasse Tyson? Yes, it's fully reduced. Partially, it's, it's, it's basically activated.
16:11 Speaker 03 It's activated, correct.
16:12 Neil deGrasse Tyson? To do things.
16:13 Chuck Nice? And it does damage.
16:14 Speaker 03 Yeah.
16:14 Chuck Nice? Yeah.
16:15 Speaker 03 And so it can cause damage. And mitochondria have preserved a little bit of their own genome. They used to have a much larger genome when they were bacteria, but now that genome is shrunk. In, in humans, they only encode 13 protein genes, but they're essential for the function of mitochondria. And the mechanism to replicate that DNA, to copy that DNA as mitochondria divide, it's not as accurate as, as the mechanism for our own DNA replication. The more errors creep in. And so mitochondrial aging is a big problem with our aging.
16:53 Gary O'Reilly? Is that a single point of failure in terms of
16:55 Speaker 03 It's not a single point. I think aging
16:58 Neil deGrasse Tyson? He's blaming it on the mitochondria.
16:59 Speaker 03 Yeah.
17:01 Gary O'Reilly? Some of them might argue.
17:03 Chuck Nice? Aging is like a cascade failure.
17:06 Speaker 03 But I do like to say that the reason my grandson has a lot more energy than I do is because he has much better mitochondria.
17:14 Chuck Nice? Right. Something's going on with the mitochondria for your skin, because your skin's perfect. I don't know how old you are, but, you know, clearly I look at your hair and I'm like, okay, this guy's old. But, but I look at your skin, I'm like, but he stole his skin off of a teenager.
17:29 Neil deGrasse Tyson? I thought, black don't crack.
17:31 Chuck Nice? That's true, black don't crack.
17:32 Neil deGrasse Tyson? And that includes
17:33 Speaker 03 I think you're absolutely right.
17:35 Neil deGrasse Tyson? The subcontinent.
17:36 Chuck Nice? Yeah, it doesn't make a difference.
17:37 Speaker 03 It's the dark skin.
17:37 Chuck Nice? It's the dark skin.
17:38 Neil deGrasse Tyson? Yeah, it's just melanin.
17:39 Chuck Nice? Yeah, that's just melanin.
17:40 Neil deGrasse Tyson? At the end of the day. So this reduced chemistry that makes it Chemically active that could not have been useful before Earth's atmosphere became oxygen-rich.
17:53 Speaker 03 That's right.
17:53 Neil deGrasse Tyson? So we had, so that-
17:55 Speaker 03 And that happened because of the cyanobacter-
17:57 Neil deGrasse Tyson? Yeah.
18:00 Neil deGrasse Tyson? So cyanobacteria basically turned a carbon dioxide atmosphere into one that had a presence of oxygen. And then anything that needs oxygen can-
18:09 Speaker 03 Can thrive.
18:10 Neil deGrasse Tyson? Can now thrive, but it couldn't before then.
18:12 Speaker 03 That's good.
18:12 Neil deGrasse Tyson? So that helps age date, or time date, I should say.
18:16 Speaker 03 It's about 2 billion years.
18:17 Neil deGrasse Tyson? That helps time date these activities, yeah. Interesting.
18:20 Gary O'Reilly? That's the watershed moment for-
18:21 Neil deGrasse Tyson? Ooh, very, very good.
18:23 Speaker 03 Yeah, look at you.
18:24 Neil deGrasse Tyson? Watershed.
18:24 Speaker 03 I like that, that was good.
18:26 Gary O'Reilly? So there's something called senescent cells, where they age and they secrete these sort of inflammatory-
18:31 Speaker 03 Yeah, so senescent cells are another, I mean, I said you can have aging at every level. And aging at this, at a cellular level is often due to senescence. And senescence is interesting. It may have evolved originally as a anti-cancer mechanism, or as a mechanism to get rid of defective cells.
18:52 Gary O'Reilly? Yeah.
18:53 Speaker 03 So what happens is, if a cell gets DNA damage, it has a number of enzymes to repair the damage, to sense and repair the damage. But if the damage is too extensive, then it triggers pathways to either kill the cell-
19:10 Neil deGrasse Tyson? Right.
19:10 Speaker 03 Commit suicide, or to send it into the state called senescence.
19:14 Gary O'Reilly? Yeah.
19:15 Speaker 03 That can also happen, you know, due to other kinds of stresses. And what senescent cells do is they no longer function normally, and they no longer divide, but they secrete inflammatory compounds. And the purpose is to signal to the immune system that there's something wrong here, and come and repair the damage around this site, maybe it's a wound, or infection, or something.
19:38 Gary O'Reilly? They call the cavalry.
19:39 Speaker 03 And, exactly, call the cavalry.
19:41 Neil deGrasse Tyson? So it has utility-
19:42 Speaker 03 It has, it has utility early in life.
19:44 Neil deGrasse Tyson? Early, until it doesn't.
19:46 Speaker 03 But later in life, you get too many of these events.
19:49 Neil deGrasse Tyson? Right.
19:49 Speaker 03 Build up of senescent cells, systemic inflammation, which causes organ damage, more senescence. And so it's a big problem in aging.
19:59 Chuck Nice? Wow. Yeah, and that's why you see so many medical reports now that talk about the dangers of inflammation.
20:07 Speaker 03 Absolutely.
20:08 Chuck Nice? Totally. Like, it doesn't make a difference what kind of inflammation. The idea is to eliminate inflammation as much as you can, no matter what.
20:15 Speaker 03 Sure. And actually, people know, for example, in the COVID pandemic, the cause of death is often triggered by inflammation.
20:25 Chuck Nice? Right.
20:25 Speaker 03 Not by necessarily directly by the virus.
20:29 Chuck Nice? By the virus itself. It's a reaction. So it's the cytokine storm that was created as a reaction to the virus itself. Cytokine? Cytokine. Please explain. Cytokines are, if I'm not mistaken. Or we can get him to answer. Oh, can you answer that?
20:44 Chuck Nice? Yeah, because I'm not an expert.
20:45 Speaker 03 I'm not an immunologist.
20:50 Chuck Nice? But yeah, the cytokines was released when we respond to what our body thinks is an attack on us. And. Sometimes it goes into overdrive. And goes into overdrive, yeah.
21:02 Gary O'Reilly? Are we anywhere close to being, or is this the epigenetics thing where we can deal with these senescent cells?
21:08 Speaker 03 No, but there is a new field emerging, which is cellular reprogramming.
21:14 Chuck Nice? Ooh, yeah, that sounds sexy.
21:17 Speaker 03 To explain that, if you start from a single fertilized egg, it divides into many cells, becomes something called a blastula, and then, or a blastocyst, and then you, it divides further and further, and then forms specialized stem cells, and each of those specialized stem cells give rise to certain kinds of tissues.
21:41 Chuck Nice? Yes, right.
21:42 Speaker 03 Okay, so some stem cells will only generate cells of the blood system, including white blood cells, red blood cells, and so on. That used to be thought of as unidirectional. You go, you can't go backwards. You can't go back from a skin cell, back to a fertilized egg or an early embryo. But that turned out not to be true. Okay, and I actually, it was done in a natural way when Dolly the Sheep was cloned, but actually even earlier, when John Girdon cloned the skin cell of a frog and cloned an entirely new animal from it.
22:21 Chuck Nice? Wow.
22:22 Speaker 03 And, and that meant that somehow these marks on the DNA had been erased and/or changed.
22:30 Neil deGrasse Tyson? Just historically, that completely changed the public dialogue about our source of stem cells.
22:39 Chuck Nice? Right.
22:39 Neil deGrasse Tyson? Because we, we only were getting them from aborted fetuses.
22:43 Chuck Nice? Blood, yeah.
22:44 Speaker 03 From fetuses.
22:44 Neil deGrasse Tyson? From fetuses. And so that was a complicated ethical issue for many people.
22:50 Chuck Nice? Right.
22:50 Neil deGrasse Tyson? And then, once this, that blew open that whole field.
22:53 Speaker 03 Right, well, that wasn't Girdon and Dolly the Sheep and others, but it was actually Shinya Yamanaka, a Japanese scientist, who showed that if you were to introduce just four factors, these are genes for proteins that regulate other genes.
23:12 Chuck Nice? Got you.
23:13 Speaker 03 If you were able to introduce those four factors, you could take a fully differentiated cell, like a skin cell or a liver cell or a heart cell, and you could make it go backwards in development, all the way back to what's called a pluripotent stem cell. Pluripotent means it can make any tissue.
23:31 Chuck Nice? Right.
23:31 Speaker 03 And so, that eliminated the need for what you said, which is getting...
23:36 Gary O'Reilly? Did he not win a Nobel for that as well?
23:37 Chuck Nice? He better had.
23:38 Speaker 03 He and John Girdon shared a Nobel Prize. And here's an interesting thing. John Girdon's paper for which he won the Nobel Prize was published the year Shinya Yamanaka was born.
23:49 Chuck Nice? No. Wow.
23:51 Speaker 03 That's how far apart they are in age.
23:53 Chuck Nice? And all that time, all that work, and then he just comes along and takes credit for it. Look at that, would you, look at that.
23:59 Gary O'Reilly? We've had, we've had sort of variations of this with David Sinclair, who we've had a guest as a guest, took mice that were blind.
24:07 Chuck Nice? Correct.
24:07 Gary O'Reilly? It sounds like a nursery rhyme.
24:09 Neil deGrasse Tyson? Three of them.
24:09 Gary O'Reilly? Back start.
24:13 Gary O'Reilly? You did it, didn't you?
24:13 Neil deGrasse Tyson? Yeah, yeah. Somebody had to go there.
24:15 Gary O'Reilly? You did.
24:16 Neil deGrasse Tyson? Go, go.
24:17 Gary O'Reilly? And turned them into sight, cured their blindness.
24:21 Speaker 03 Yeah.
24:21 Gary O'Reilly? So, I mean, if that's the case, how far are we from?
24:25 Speaker 03 I would say it's early days. Yeah. Okay.
24:29 Gary O'Reilly? I can tell you that I'm aware that this has happened, and then my question is, just the distance between this and doing other things on a grander scale. Mine's the one thing, larger primates.
24:39 Speaker 03 Yeah, and curing blindness, it's a little further down the line, is what you're saying. It's a little... But, the idea is, we do have, would you say we now have a, not a blueprint, but maybe a template, that we know we can take these programming cells and use them to maybe change our makeup? I think the biggest use of that is in something called regenerative medicine, where if you want to replace tissue that normally can't be replaced, for example, damaged heart muscle in a heart attack, or pancreatic tissue which has been destroyed
25:24 Speaker 03 and you have diabetes, or cartilage, for example, for osteoarthritis. Absolutely. And maybe one day, I'm hoping, even hair.
25:35 Speaker 03 So, if you can... It looks good on you, though. Very few people can pull this off, okay? Anyway, so if you can do that, regenerative medicine is a huge area of research. Yeah. And they're making good progress in some things.
25:50 Neil deGrasse Tyson? Just to be clear, I've always been disappointed in humans for not being able to regenerate limbs the way newts do.
25:56 Speaker 03 Exactly. That's because newts have stem cells all over... All over their body? All over their body. Their whole makeup. Yeah, it's spread out throughout, and so they can...
26:06 Neil deGrasse Tyson? I'm just saying, we're old enough to remember reading biology books, "Humans are the top of the evolution," back when we spoke that way.
26:13 Speaker 03 Unless you lose an arm.
26:18 Neil deGrasse Tyson? I went through the list of all the other animals that do things way better than we do, and I quickly read...
26:24 Gary O'Reilly? It's not a short list.
26:26 Speaker 03 It's humbling to know that we have about the same number of genes as a worm or a weed. Right, yeah, there you go.
26:33 Gary O'Reilly? You put us in our place.
26:34 Neil deGrasse Tyson? Yeah.
26:35 Speaker 03 Anyway, but going back to stem cells, the thing with aging is, can you...
26:41 Speaker 03 Take a fully grown or an aged individual, apply these kinds of factors, and get their tissues or their stem cells to be regenerated. Right. Because one problem with aging is that our stem cells also age. Right. They decline in number and in quality. So if you were able to take, use a method that would somehow either rejuvenate tissue or actually regenerate stem cells, that would be a big thing. And people have done experiments to do this kind of thing in mice. And they say that the mice, I mean, the papers report that the mice look healthier, they seem younger by many criteria and so on. But how to do this safely?
27:25 Speaker 03 And the bald mice, did they get hair back? No, but their fur looked better. Oh, okay, okay. That's not bad. So, so the question is, how can you do this in humans in a way that's safe, that doesn't cause cancer, that is at the right dose and so on? Right. And that's a big challenge. It is. So I, I think it's promising, but like many of these things, you know, the aging field, I should say, is full of hype. Okay? Yeah. And it's very promising, but there's a lot of work to be done before it's ready for prime time. Mm-hmm.
28:00 Gary O'Reilly? Are we at this sort of Frankenstein moment? I mean, you've done a Frankenstein show before with the, let me get his name right, David Andrussevich.
28:07 Speaker 03 Yes.
28:08 Gary O'Reilly? Mm-hmm, mm-hmm. You know, the cells were, we've said there can be death to the organism, but cells will remain alive. And now we've got the Yamanaka factors. Are we getting to that thing when we can create? Or are we just fantasy talking here?
28:24 Speaker 03 You mean, create a new individual?
28:26 Gary O'Reilly? Hmm.
28:27 Speaker 03 Or the same individual?
28:28 Gary O'Reilly? Well, the same individual.
28:29 Speaker 03 You could certainly clone yourself. Right. That's theoretically and practically possible. They've cloned all kinds of mammals. There's no reason why they can't clone a human being. Except that all countries have decided that's a bad thing to do. But that's not the same as rejuvenating the same individual.
28:49 Chuck Nice? Right, right. Which, by the way, for selfish purposes rejuvenation is a hell of a lot better than cloning. Because that clone is not me.
28:59 Speaker 03 Exactly. People forget that.
29:02 Neil deGrasse Tyson? Yeah, and there's all this fantasies of in the multiverse where you have an infinite number of possible molecular outcomes of all organisms, they're imagining themselves in another universe in a way being reincarnated and living forever. It's like, no, that's a different person.
29:19 Chuck Nice? That's just a different person in a different timeline.
29:20 Speaker 03 And by the way, these transhumanists, you know, people who think that they're going to dump their brain into a computer and then maintain their consciousness. A simple question to ask is, what if you make two copies of it? Which one's the real you? And you immediately have a paradox.
29:36 Chuck Nice? Absolutely.
29:37 Gary O'Reilly? The copies that you make will be of you of that moment, but you've in the timeline are still proceeding. They would be stuck.
29:43 Neil deGrasse Tyson? You still get to go to the beach and have friends and your your brain in a jar does not, right?
29:48 Chuck Nice? Oh, gosh.
29:49 Neil deGrasse Tyson? Or your brain in the silicon chip.
29:50 Gary O'Reilly? It's you from whenever it was you created it.
29:53 Neil deGrasse Tyson? So, so I heard long ago, and I checked it out, and I think it's true, that all mammals live for about the same number of heartbeats, except for humans who live two or three times that. Except if you go back far enough in time when we were just living in caves, we were right with all the rest of the mammals. So first, is that true? Second, there are animals, not mammals, that live much longer than we do. I'm thinking of the Galapagos tortoise, for example. So do you guys study other animals to get insight?
30:25 Speaker 03 So there is a whole field devoted to looking at lifespan of different species. And you are right that, at least among mammals, Jeffrey West, who's written a book called "Scale," shows that the number of heartbeats is roughly the same. That has to do with the fact that smaller animals have a higher metabolic rate. They have a faster metabolism. And they almost need to because their surface-to-volume ratio is larger, they dissipate heat more.
30:54 Neil deGrasse Tyson? We did a whole explainer on surface-to-volume ratios.
30:57 Speaker 03 And so they need to maintain a higher metabolic rate. That's one of the reasons.
31:04 Neil deGrasse Tyson? Well, that's only one of the reasons why they have higher heart rate. That's not a reason why they should die sooner.
31:10 Speaker 03 Ah, the why we should die sooner is, has an evolutionary explanation. And that is, evolution doesn't care how long you live. It only cares about fitness. Fitness, in the biological sense, is the likelihood that you're going to be able to successfully pass on your genes.
31:30 Neil deGrasse Tyson? And people always misinterpret that as being physically fit, or stronger, or whatever. Survival of the fittest. I'm in great shape. Yeah, Darwin should have found a different word for that.
31:41 Speaker 03 So, evolution cares about fitness. Now, at the same time, for most of our history, and certainly the history of all other species, resources are limiting. And so, you have to select, do you put more of your resources into maintenance and repair of the individual animal, or do you put it into growth and reproduction? There's always a balance, if you have limited energy. So, in the case of a mouse, which lives about two years in the wild, there's no sense in having a mouse live for 40 years, because long before that, it's going to be eaten.
32:21 Neil deGrasse Tyson? Eaten, yep.
32:22 Speaker 03 Exactly. You beat me there. Or it'll die of starvation, or drought, or something. And so, in the case of a mouse, evolution has favored selection of a species that grows very quickly and reproduces prolifically. That's a mouse. If you get to a large animal, like a bowhead whale...
32:44 Speaker 03 Let's take a, an even, even bigger than an elephant. They can live for two, three hundred years and they have a very relatively slow metabolism.
32:51 Chuck Nice? Wow.
32:52 Speaker 03 An even slower metabolism is not a mammal, but it's still a vertebrate called the Greenland shark. Seven hundred years.
32:59 Gary O'Reilly? Whoa.
33:01 Speaker 03 A vertebrate, living for seven hundred years, very slow metabolism.
33:04 Neil deGrasse Tyson? Wait, wait, wait, wait, wait. How do you know that? We didn't even have marine biology seven hundred years ago.
33:09 Speaker 03 They, they can do things like carbon dating.
33:14 Gary O'Reilly? They cut one open and it was all seven hundred rings.
33:19 Neil deGrasse Tyson? Okay, I'm just, I'm just weird.
33:21 Gary O'Reilly? So you've got the mayfly lives a day.
33:24 Speaker 03 Mayfly lives a day, exactly.
33:25 Gary O'Reilly? And then between that, you've gone from there to a Greenland shark.
33:28 Speaker 03 And your Galapagos. And there are actually other animals that are thought not to even age biologically.
33:33 Gary O'Reilly? What's the immortal jellyfish?
33:34 Speaker 03 Like the hydra and the immortal jellyfish. These things have.
33:37 Neil deGrasse Tyson? Wait, there's an actual animal called the hydra?
33:39 Speaker 03 Yes.
33:40 Chuck Nice? Awesome.
33:40 Neil deGrasse Tyson? Not just in, in.
33:41 Chuck Nice? Not just in G I Joe?
33:42 Neil deGrasse Tyson? No, no.
33:43 Chuck Nice? Oh, no, Marvel.
33:44 Neil deGrasse Tyson? No, no, no, in, in, in.
33:46 Speaker 03 In mythology.
33:47 Chuck Nice? Oh, you mean the real hydra?
33:49 Neil deGrasse Tyson? Yes.
33:49 Chuck Nice? Oh, yeah.
33:50 Speaker 03 This is a freshwater, a small animal. And, and they're full of stem cells, so they're constantly regenerating themselves. But if you followed an individual, it would also age only very slowly. It's just in the wild, it, it, it dies for other reasons before actually aging.
34:07 Chuck Nice? Mm-hmm.
34:08 Speaker 03 So, so there's a whole range.
34:10 Neil deGrasse Tyson? So humans might be the only species that dies of natural causes in the world. I mean, if you want to think about it that way.
34:18 Speaker 03 Possibly, you know.
34:19 Neil deGrasse Tyson? We're apex predator.
34:20 Speaker 03 Yeah.
34:21 Neil deGrasse Tyson? So.
34:22 Speaker 03 Yeah, I think that may be true. In fact, there, there's a book written by Stephen Ostad called Methuselah Zoo, which, where he talks about all these animals.
34:32 Chuck Nice? He loves that title. Methuselah Zoo.
34:34 Neil deGrasse Tyson? Love it.
34:34 Speaker 03 And it's, it's a great book.
34:36 Neil deGrasse Tyson? So that reminds me, because Methuselah's the oldest person in the, in the Bible.
34:40 Chuck Nice? Right.
34:41 Neil deGrasse Tyson? In the, in the.
34:42 Chuck Nice? In the Old Testament.
34:43 Neil deGrasse Tyson? Old Testament Bible. The oldest star we know of in our galaxy is called Methuselah.
34:47 Chuck Nice? It's called Methuselah.
34:47 Neil deGrasse Tyson? Yeah.
34:48 Chuck Nice? Right.
34:48 Neil deGrasse Tyson? So Methuselah had a lot of influence.
34:50 Chuck Nice? Yeah. And that star too is lying about its age.
34:56 Chuck Nice? Who knew that?
34:59 Speaker 03 Anyway, in this book, he points out.
35:02 Neil deGrasse Tyson? Methuselah Zoo.
35:03 Speaker 03 In Methuselah Zoo, he points out how all these species have such different lifespans. And it's because of this evolutionary selection, but it's actually worse than that. It's, the fact is, evolution will select for things that help you early in life, even if they cause a problem later in life. So many of the things that cause aging are related to growth, for example, or to cancer prevention, you know, prevention of, or senescent cell creation. These things all help us early in life, and they're a problem later in life. But evolution doesn't care what happens to you when late in life.
35:42 Neil deGrasse Tyson? When you're not making babies.
35:43 Speaker 03 Right, exactly.
35:43 Chuck Nice? Yeah, because that's the whole deal.
35:45 Gary O'Reilly? So what helps us survive in infancy and then go on to reproduction is the key component of our decline and demise?
35:52 Speaker 03 Not always, not everything, but there are things that happen to us early in life that are selected for early in life that cause aging.
36:00 Chuck Nice? So the real deal is just keep having babies your entire life, uh, and then you'll never age. However, you will eventually kill yourself because of these kids.
36:13 Speaker 03 So we're an outlier, we're an outlier. We live about twice as long as we would based on our size.
36:21 Neil deGrasse Tyson? But only post caveman life, right?
36:23 Speaker 03 Um, yeah, 40,000 years.
36:25 Neil deGrasse Tyson? Exactly, so only, I mean, half of everyone died by 30, and so we're not 2X other mammals at our size, right?
36:33 Speaker 03 Yeah, and one last thing is, there's a group of animals, mammals, the bats, they live much longer, they're about the same size as a mouse, in terms of mass.
36:44 Neil deGrasse Tyson? You're a flea or a mouse.
36:45 Speaker 03 They live about 10 or 20 times as long as a mouse. And the reason is, they can fly around. So that means two things, they can escape predators more easily.
36:57 Chuck Nice? Right.
36:58 Speaker 03 And they can also forage over a much wider area for food. And, and when they roost, they roost in ceilings of caves, so they're not as accessible.
37:08 Gary O'Reilly? They've been designed to survive longer.
37:10 Speaker 03 And so there is worth it for evolution to make them live longer, because they'll still keep producing more babies.
37:16 Chuck Nice? Yeah, so you gotta be grandpa Munster, is basically the deal.
37:21 Neil deGrasse Tyson? Grandpa from the Munsters.
37:22 Chuck Nice? The grandpa from the Munsters, if you wanna live long. Sleep hanging upside down, away from predators.
37:27 Gary O'Reilly? So, if we're looking at aging, we all do it, can't help it, more or less. What have been the attempts to reverse the aging, I'm not talking potions and lotions here, so let's go through the laundry list. The sort of young blood transfusion.
37:44 Chuck Nice? Oh yeah.
37:44 Gary O'Reilly? How successful has that been?
37:46 Speaker 03 It's not incredibly successful, but the science underlying it is solid. If you connect an old rat with a young rat, by that I mean you connect them so that their blood systems.
38:01 Chuck Nice? Sharing the same circulation system.
38:03 Speaker 03 Exactly. Then it turns out that the old animal benefits from the blood of the young animal, but even more so, the young animal suffers from the blood of the old animal.
38:13 Gary O'Reilly? Wow.
38:14 Speaker 03 And so, this means there are factors in blood that change as we age.
38:20 Neil deGrasse Tyson? Such a thing as old blood.
38:22 Speaker 03 Exactly, or young blood, and that's why I call it vampire blood. So, that's the science, and, and the research is now about finding out what these factors are, what they do, and once you know that, you might be able to figure out whether you can use them to our benefit. But, people have not waited for that. What's happened is, the very first time these people from Stanford, Rando and others, published this, they got creepy phone calls from rich people asking you.
38:54 Chuck Nice? Like Keith Richards.
38:56 Speaker 03 And, and companies started sprouting up, getting blood from young donors.
39:04 Speaker 03 And extracting the plasma and selling them up, you know, at $8,000 a pint or something to, you know, rich old people. And one of them, the FDA wanted to shut it down and then they sprouted up under a different name. And it's all, the whole thing was like the Wild West. But there's real science under it and, and, and that's an ongoing area.
39:24 Gary O'Reilly? Okay, stem cells, we've kind of addressed as to how you can through the Yamanaka factors.
39:28 Speaker 03 Yeah.
39:29 Gary O'Reilly? Dial up, dial down.
39:30 Speaker 03 And that's, I would consider that.
39:32 Gary O'Reilly? Yamanaka.
39:32 Neil deGrasse Tyson? What is the Yamanaka factor?
39:34 Gary O'Reilly? The Oscar winning, where he sort of can.
39:36 Neil deGrasse Tyson? You know that Oscar winning?
39:38 Gary O'Reilly? Yes, Oscar winning. He was a bloody good actor. Unbelievably good actor.
39:42 Neil deGrasse Tyson? Nobel Prize winner. Okay, that guy. Right, that guy. Thank you. Okay.
39:46 Gary O'Reilly? The Nobel Prize.
39:47 Neil deGrasse Tyson? Get your prizes straight here. Okay.
39:50 Gary O'Reilly? The calorific restrict, or caloric restriction.
39:54 Speaker 03 Yeah, so.
39:54 Gary O'Reilly? Which is basically fasting.
39:56 Neil deGrasse Tyson? It is.
39:56 Speaker 03 It is. So lots of experiments, starting in mice, but now also in flies, worms, even in single-celled animals like yeast. If you reduce the amount of calories, it turns out that you can, the, the animals live longer, but more importantly, older animals start resembling younger animals in terms of their physiology and their biomarkers. And so the question is, can you mimic caloric restriction? And it turns out that there are many important biochemical pathways that are affected by caloric restriction. One of them is the IGF-1 insulin growth hormone factor.
40:38 Neil deGrasse Tyson? Yeah. Just to be clear, what you're saying, you wouldn't have to imitate calorie reduction, you could just consume fewer calories. So, so what you're trying to do is, we can still eat our cheeseburgers and the blueberry pie dessert. And then you hijack what would be the starvation mechanism biochemically.
41:00 Speaker 03 Exactly.
41:01 Neil deGrasse Tyson? That's intermittent fasting.
41:04 Speaker 03 Yeah.
41:04 Neil deGrasse Tyson? But I don't have to fast.
41:06 Speaker 03 Is this the GOP?
41:07 Chuck Nice? Oh, yeah, the whole point is not to fast, just to restrict you.
41:10 Neil deGrasse Tyson? No, no, no, no. Did you get what I just said? No. What he's saying, that's why I paused on it.
41:15 Speaker 03 Saying, have your cake and eat it.
41:16 Neil deGrasse Tyson? He did have your cake and eat it too.
41:19 Chuck Nice? Yes, but explain your point again, because I missed it.
41:22 Neil deGrasse Tyson? Okay, so the point is, what he said, he just slipped it in.
41:25 Chuck Nice? Right.
41:26 Neil deGrasse Tyson? But, but I caught him.
41:27 Chuck Nice? Okay.
41:29 Neil deGrasse Tyson? He's saying fasting, fasting will prolong your life.
41:33 Chuck Nice? Absolutely.
41:33 Neil deGrasse Tyson? So can we find a way to mimic the biochemistry of that in your body?
41:37 Speaker 03 We can.
41:38 Neil deGrasse Tyson? And the word mimic in that sentence means still eat the cheeseburger.
41:41 Chuck Nice? Right.
41:42 Neil deGrasse Tyson? And but do what the fasting would have done to your biochemistry.
41:45 Chuck Nice? I see, which, yes.
41:46 Neil deGrasse Tyson? Have your cake and eat it.
41:46 Chuck Nice? But you're doing it artificially, is what you're saying.
41:48 Speaker 03 I, in my book, I call it eating your blueberry pie and ice cream and, and getting the benefits.
41:54 Chuck Nice? Nice.
41:55 Neil deGrasse Tyson? And still getting the benefits.
41:56 Chuck Nice? Wait, so have we done this?
41:58 Speaker 03 No, well, there are, there are some drugs.
42:01 Chuck Nice? Okay.
42:01 Speaker 03 No, no, I'm, I'm not working on it.
42:03 Chuck Nice? He's like, I'm out this game.
42:06 Speaker 03 I should say.
42:06 Chuck Nice? He was like, did you see? Yeah, the way he said it. The way he just went like this, no, no, no, not me. They keep trying to keep me working. I'm telling you right now, I'm out.
42:15 Speaker 03 But if you do know how to do it, tell Chuck, because he'll set up a company.
42:18 Chuck Nice? Certainly.
42:18 Speaker 03 No, lots of companies, that's a problem. So anyway, one of the drugs that does this is called rapamycin. It's a, it's the darling of the anti-aging research community.
42:30 Gary O'Reilly? Find, isn't it?
42:31 Speaker 03 Easter Island.
42:32 Gary O'Reilly? Yes.
42:32 Speaker 03 Easter Island is where it's coming.
42:34 Chuck Nice? Yeah, rapamycin, okay, let's do it.
42:36 Speaker 03 Rapamycin was found in the soil of Easter Island in back, from bacteria in, in the soil of Easter Island that produced this compound, which turns out to be an antifungal compound. And then they found out that it may have some properties against cancer. And then eventually they found out that it actually is an immunosuppressor. And that's what made it get FDA approval as an immunosuppressive drug.
43:06 Speaker 03 Then, much later, it was found in a completely different place. It was found that it shuts down a major pathway in the cell. And that pathway is related to the... It's a pathway that senses nutrients. So it's related to caloric restriction. People then said, "Okay, let's see what happens if you give rapamycin to mice," and so on. And mice lived a bit longer, seemed a bit healthier. However, rapamycin is an immunosuppressive drug. So it's going to make you more prone to infections.
43:40 Neil deGrasse Tyson? Like steroids.
43:41 Speaker 03 And it has other side effects as well.
43:43 Neil deGrasse Tyson? Okay.
43:44 Speaker 03 So the question they have is, can you adjust the dosage so you get the benefits against aging without the problems of immunosuppression and so on? And that's still... Jury's still out on that.
44:00 Neil deGrasse Tyson? Yeah. Okay, now, there's also relativity, where you can slow down time for yourself.
44:05 Gary O'Reilly? Oh, well, that's going into space, though.
44:06 Neil deGrasse Tyson? Yeah, well, right.
44:07 Gary O'Reilly? That's one way to defeat aging, right?
44:09 Neil deGrasse Tyson? However, you are still aging. Right. In your own body, one second per second. Right. The difference is, all your friends are aging faster than you. Much faster. Right, so you're not going to live older than you would have as an organism. Right. You'll just live longer than everybody else. Exactly.
44:24 Gary O'Reilly? Isn't that the...
44:25 Neil deGrasse Tyson? And then when you return, all your friends would have been dead. They'd be dead.
44:27 Gary O'Reilly? The Kelly Twins, where they did the experiment.
44:29 Neil deGrasse Tyson? Oh, yes, yes, we had one of them on this program.
44:32 Gary O'Reilly? Yes.
44:32 Neil deGrasse Tyson? Scott Kelly, astronaut who went up. That's right. And... His brother stayed here. Brother stayed here, they're identical twins. And you can calculate how much younger one would have been, like a fraction of a second. That's what he gained? He gained half a second, huh?
44:48 Gary O'Reilly? Does it show?
44:49 Neil deGrasse Tyson? So basically, yeah.
44:52 Neil deGrasse Tyson? I don't remember the fraction, but it was... They were not going so fast that the speed of light...
44:57 Gary O'Reilly? That's the definition of sibling rivalry.
44:59 Neil deGrasse Tyson? Yeah. The most expensive anti-aging regimen ever.
45:24 Neil deGrasse Tyson? So, as you surely know, in physics, we speak of this thing called entropy. Where left to itself, a system will always degrade to lowest energy, highest disorder.
45:41 Speaker 03 The key is left to itself.
45:43 Neil deGrasse Tyson? Yes, yes, so, we can create any manner of complexity on Earth, because we're not a closed system. We're open to the sun. So the sun is gaining entropy by helping us out. Eventually, it's gonna die and nothing's gonna help it.
46:01 Chuck Nice? Right.
46:01 Neil deGrasse Tyson? Right? So, do you guys in molecular biology think of entropy?
46:06 Speaker 03 There's no question that entropic forces exist, but of course, living systems all use external energy to keep it alive. And part of the energy is used to do this maintenance and repair of the damage. But, it never, it's not perfect. And so, eventually, even if you keep repairing DNA damage, repairing cells, getting rid of defective cells, all of that stuff which takes energy, it's not perfect. And eventually, the system gradually decays. But it means it decays at different rates for different species.
46:42 Neil deGrasse Tyson? Interesting. Or different parts, different systems, even within your own body.
46:46 Speaker 03 Oh, that's something that you, that, very interesting. So if you were to, people were to analyze your different organs, they'd find that they all had different ages.
46:55 Chuck Nice? Yes.
46:56 Speaker 03 To say someone's biological age is a number...
46:59 Neil deGrasse Tyson? Different ages mean different time distance from its birth to its death.
47:03 Speaker 03 Correct.
47:04 Neil deGrasse Tyson? Right, because obviously, it's all, physically the same age.
47:07 Speaker 03 Physically, chronologically, chronologically, it's the same age.
47:11 Neil deGrasse Tyson? Yes, but physiologically...
47:12 Chuck Nice? Physiologically, they're at different ages. But it doesn't make a difference, because if I got an old heart and a young pancreas, I'm still gonna die.
47:19 Neil deGrasse Tyson? With my heart issue.
47:20 Chuck Nice? With my heart issue.
47:21 Neil deGrasse Tyson? So that was always what I suspected, that people who live very long, all of their organs somehow are aging at the same rate. Physiologically.
47:31 Speaker 03 Well, I'm not, I don't know if that's true, but maybe they're still aging differently, but the lead organ, the organ that's aging fastest is still slower than other people.
47:41 Neil deGrasse Tyson? Right, right. If they die, it's not gonna be from that. So, given what you just said, I didn't put two and two together here until just now. In the second law of thermodynamics, one of its stipulations is if you have sort of usable energy over here, and you convert it into another kind of energy over here, there's always energy losses, always. That's why you cannot make a perpetual motion machine.
48:07 Speaker 03 Right.
48:07 Neil deGrasse Tyson? All right, and so, the body is all about converting energy of one kind into another. You have chemical energy in food, and you turn it into...
48:16 Speaker 03 ATP.
48:17 Neil deGrasse Tyson? Yeah, exactly. Remind us about that. We all learned it in biology class. The ATP cycle, is that right?
48:23 Speaker 03 ATP is adenosine triphosphate. It's a molecule with high-energy bonds. So you can think of it as a universal currency, just like, in our world, electricity is the universal currency. So you use everything, convert it to electricity, then you can use that for everything. And so the body uses it, so you can think of it as a kind of storable form of energy that it can use.
48:48 Neil deGrasse Tyson? Right, but it's taking energy from one, it's taking energy from one thing and...
48:53 Speaker 03 Right. Typically, in our case, we're getting it from carbohydrates.
48:57 Neil deGrasse Tyson? Yes.
48:58 Speaker 03 And by burning carbohydrates.
48:59 Neil deGrasse Tyson? So it's chemical energy.
48:59 Speaker 03 It's chemical energy.
49:00 Neil deGrasse Tyson? Yeah.
49:01 Speaker 03 So that energy is used to make ATP.
49:04 Neil deGrasse Tyson? Got it. And anything else we make in our body to maintain our body temperature, because we're warm-blooded, to move, so it goes to thermal energy, kinetic energy, and the like.
49:15 Speaker 03 And most of those things involve ATP.
49:19 Neil deGrasse Tyson? And electrical energy. Right, for your brain and your heart, and signaling and all that. So I'm just saying, every time you convert from one form of energy to another, you're getting less energy than you started with. Right. So there is a decay in there.
49:31 Speaker 03 Yeah.
49:31 Neil deGrasse Tyson? Eventually.
49:32 Speaker 03 Interesting, yeah.
49:33 Neil deGrasse Tyson? So you describe this sort of implicit value of death to a species. Because it doesn't need you after a certain point of your fertility. We're beyond that now and we're what we call civilized. And so there are people who want to do anything they can.
49:51 Chuck Nice? To stay alive for as long as they can.
49:53 Neil deGrasse Tyson? To stay alive for as long as they can. And you're in that business scientifically. What is the ethics?
50:00 Speaker 03 I should say, my own lab has never worked on aging. I went from zero to expert in one book.
50:06 Neil deGrasse Tyson? Oh, okay.
50:07 Speaker 03 Okay. My, my lab works on protein synthesis, which is a central component of aging. But I don't actually do aging research myself.
50:17 Neil deGrasse Tyson? Okay, but surely you've thought about the ethics of it.
50:20 Speaker 03 Yeah.
50:20 Neil deGrasse Tyson? Why wouldn't you have?
50:21 Speaker 03 Oh, definitely, yeah.
50:21 Neil deGrasse Tyson? Yes, yes.
50:22 Speaker 03 And I also have no skin in the game, so that's a...
50:25 Neil deGrasse Tyson? Okay.
50:26 Chuck Nice? That means we can get a very, a truly objective...
50:28 Neil deGrasse Tyson? Other than beautifully soft skin.
50:30 Chuck Nice? Right.
50:32 Chuck Nice? I missed that one.
50:33 Neil deGrasse Tyson? Yeah, Chuck, I don't want to be ahead of you on any of this.
50:36 Chuck Nice? That was a good callback. I like it.
50:38 Gary O'Reilly? Chemical laws, biological laws? Any in the way to stop us going from where we are now to potential immortality?
50:45 Speaker 03 Right, so there are two issues. One is, is aging programmed? I mean, are we all programmed to die?
50:50 Gary O'Reilly? Yes.
50:51 Speaker 03 No, because evolution doesn't care about...
50:53 Chuck Nice? It doesn't care about us dying.
50:55 Speaker 03 So there are genes that affect aging, but those genes don't exist in order to make us age. They were selected for some other reason, but they happen to cause us to age. So now that we understand some of the biology of aging, you ask, can we extend that?
51:11 Gary O'Reilly? Yes.
51:12 Speaker 03 And there's no, there are no physical or chemical laws that say that we have to die at 120. I mean, 120 is about the record for humans.
51:24 Chuck Nice? Right.
51:24 Speaker 03 Very few reach that.
51:25 Chuck Nice? And by the way, whenever you see a 120-year-old, they're like, "I am ready to go."
51:31 Speaker 03 Oh, I'm not sure.
51:32 Neil deGrasse Tyson? It's like, "Don't take me to Disney World."
51:36 Chuck Nice? Not all of them, but yeah.
51:37 Speaker 03 There's a woman, Jeanne Calmont, who's the record holder at 122.
51:41 Gary O'Reilly? Oh, she was the smoker and drinker.
51:42 Speaker 03 She was, she used to smoke and drink into our hundreds. And, and reporters, after a while... Used to gather at our house every birthday. And one of the reporters said, well, see you next year, I hope. And you know what she said?
51:57 Neil deGrasse Tyson? What?
51:57 Speaker 03 She said, sure, why not? You look pretty good to me.
52:03 Speaker 03 But there's no physical or chemical law that says, you know, at 120.
52:09 Neil deGrasse Tyson? You gotta go.
52:10 Speaker 03 You gotta go. There are species, as I said, that live 700 years, vertebrates. Of course, the question is, can we change our biology to make us live much longer? And still keep us humans? You don't want to be a very slow metabolic animal like a Greenland shark. You still want to be human and you still want and you want to live much longer. Now, there are people, I would say, at the one end of the anti-aging research community, including perhaps somebody you've had on your show, who think that it's it is possible. You can just keep extending life and that'll buy you enough time to do more research and you'll extend more life.
52:53 Neil deGrasse Tyson? And we eventually, there's a generation that would reach the escape velocity.
52:56 Speaker 03 Exactly.
52:56 Neil deGrasse Tyson? Where the prolonging of your life is one year per year. And then you live forever.
53:02 Speaker 03 Yeah, now, I I'm highly skeptical, as are most scientists in this field. Because aging is a is a multifactorial process. And to be able to do this in a way that's safe, that's efficacious, that actually works, I think is is going to be very, very hard. Certainly not impossible.
53:22 Neil deGrasse Tyson? The Google software that uses AI for folding proteins, which won a Nobel Prize, if if memory serves. Won't that solve all your protein folding problems?
53:33 Speaker 03 No, this is this is different from. I I think AI will have a big influence on biology. And maybe one day it will help with things like aging.
53:44 Neil deGrasse Tyson? One day, 18 months from now. Some time in the distant future. In the future, distant future of AI.
53:50 Speaker 03 What time is it?
53:53 Speaker 03 Let's say I'm highly skeptical, but there is no physical law. But I'd say there's also no physical or chemical law that says you can't colonize other galaxies, or even Mars. And so, you know, whatever Elon may say, it's not gonna happen tomorrow. So I think-
54:13 Chuck Nice? And I think we should get down here, kinda worked out first. I'm sorry, but yeah, why don't we make this place habitable?
54:20 Neil deGrasse Tyson? Alright, so what happens the day we as chiefs escape velocity? What happens to civilization?
54:25 Speaker 03 I think before that, a number of things will happen. For example, more people may live to be a hundred, or well into their nineties or early hundreds. That itself will cause a huge shift in society. For example, fertility rates everywhere are dropping. And so what you're gonna have is-
54:46 Neil deGrasse Tyson? It's an aging of the population.
54:47 Speaker 03 Yeah, society where there's very little turnover. Same people are living longer and longer, very, very slow turnover. To me, that means a less dynamic, less vibrant society. If you look at the history of science, or any fields, even literature, people have done their most creative work when they're young. And it's not just about physiological age. When you're young, you're looking at things fresh, you're not as opinionated, you're not dogmatic, and that allows you to think out of the-
55:22 Neil deGrasse Tyson? You have to convince the old people that they're less useful to society. How do you do that?
55:26 Speaker 03 Well, one of the reasons I'm retiring is because, you know, I decided four or five years ago to close down my lab. It's gonna happen late this year. It's partly because I do believe that when you've had your time, you know, you should step aside and let younger people carry on.
55:46 Chuck Nice? Carry on.
55:46 Neil deGrasse Tyson? When Einstein was given the option to be operated on, basically on his deathbed, he said, "No, my work is done."
55:53 Chuck Nice? My work is done. Yeah, I would've said, "What kind of doctors are you? Save me."
56:00 Gary O'Reilly? What you were talking about is inverting the population pyramid. So it goes from a small peak of aging population to a rather large one and less young people. We are basically diving down a drain here.
56:11 Neil deGrasse Tyson? Well, it would be, it would be, it would be more stable the whole time.
56:14 Speaker 03 More stable. Stable thing would be good, but if the turnover is very slow and people just live for very long. I mean, as people get older, they accumulate power, they accumulate wealth, they accumulate influence. And of course, the three go together. And that then means that it's harder for younger people.
56:36 Neil deGrasse Tyson? To gain entrance.
56:37 Speaker 03 To gain entrance, to make it and so on.
56:40 Neil deGrasse Tyson? Sococultural fact.
56:43 Speaker 03 And that's a, that's a, that's a real problem.
56:46 Chuck Nice? We're seeing that right now in a certain party in, in America where they're like, yo, everybody who is in charge is 80 years old, get out of the way because we have a different way to do things and we want to get to it.
56:59 Speaker 03 And so, so I think societies would be more stagnant and less dynamic and less creative. People will always throw exceptions at me. Oh, so and so was so brilliant, old and late in life. But those are exceptions, you know, that's not what you plan a society around. But here's the problem. If somebody gave you a pill and said, this is going to give you 10 extra years of healthy life. Nobody wants to be sick for 10 years. 10 years of extra healthy life. Would you take it? I know I would.
57:31 Chuck Nice? Yes.
57:32 Speaker 03 Okay. Almost all of us would. And this is the conflict between what we as individuals want and what's good for society.
57:39 Neil deGrasse Tyson? Right. Because at the end of those 10 years, if you're given the option again, you'll probably say yes again.
57:42 Speaker 03 Exactly.
57:43 Chuck Nice? Absolutely. Especially if it's healthy life.
57:46 Neil deGrasse Tyson? So that thought experiment takes the larger question down to its individual parts and you realize people really do want to live forever.
57:54 Chuck Nice? They do, well, because yeah.
57:55 Speaker 03 They do. Because this is, as you say, the only life we know. It's our existence. We, we fear the, the loss of existence. And that's, that's the problem.
58:05 Chuck Nice? But you know, there's, I mean, I'm about to get philosophical. The great thing about death is that when you look at it full on and embrace it for what it is, it allows you to wake up and... Treat each day as something special because you know this thing is going to be over. If you take that away, you know, I don't give a damn.
58:27 Speaker 03 People have said that, that having a finite life gives you the drive, the incentive to accomplish things. Otherwise, there's always tomorrow.
58:36 Chuck Nice? There's always tomorrow.
58:37 Speaker 03 Okay, so that that is true, but at the same time, there's all, there's an old joke. Who would want to live to be a hundred? And the answer is always someone who's ninety-nine.
58:45 Chuck Nice? Exactly.
58:48 Speaker 03 So you may, you may be philosophical about death in the abstract, but you don't want to die next year.
58:53 Chuck Nice? Well, no, yeah, you're absolutely right. I don't want to die, period, you know, because my life is pretty damn good. So, you know, as long as.
58:59 Neil deGrasse Tyson? And we're not talking about people who are so mortally injured or, or ill that death feels like an escape. We're talking about someone who's fully.
59:09 Chuck Nice? Who's vibrant.
59:10 Neil deGrasse Tyson? Vibrant, yes.
59:10 Speaker 03 There's also one aspect of aging research. If you tell, if you ask most of them, they, they'll say, except for some of these outliers, they'll say, oh, we're not about extending lifespan. We're about increasing health in your life. And the idea is that you stay healthy all your life and then suddenly, you know, crash and die. And there's a poem called The One Horse Open Shay.
59:32 Neil deGrasse Tyson? I just learned about that poem. It's, it's the horse that.
59:36 Speaker 03 The carriage was perfectly designed so that it wore out it, all its parts wore out equally.
59:42 Neil deGrasse Tyson? Exactly at the same time.
59:43 Speaker 03 And one, one minute the farmer was riding along, the next minute he was on the ground, surrounded by a bunch of debris. Because his whole carriage collapsed. Now that's what people are, are asking when, when you say, we're going to compress the period of morbidity in old age. And we're just going to suddenly decline and die. Nobody's shown that that can actually happen.
1:00:07 Chuck Nice? Uh, Apple is working on it, believe me.
1:00:10 Speaker 03 Nobody's shown that, so if they increase our health span, it's equally possible that they may extend.
1:00:17 Neil deGrasse Tyson? Good phrase, not lifespan, health span.
1:00:19 Speaker 03 Yeah, but if they do that, if they keep us healthy in old age, it's equally possible that they extend our lives too. And that eventually we still have that slow decline.
1:00:30 Neil deGrasse Tyson? You still have the.
1:00:31 Chuck Nice? You just reach a point where now I'm a hundred and eight and it's all falling apart, but I'm not going to die tomorrow. It's still going to be a slow, hard, most death five years from now.
1:00:39 Neil deGrasse Tyson? Yeah. Of course, if we live forever, we need to find another planet because the population will continue to rise. And we will outstrip the resources of Earth. And possibly Mars, Venus, and anyplace else we search for.
1:00:52 Speaker 03 That isn't quite true.
1:00:53 Neil deGrasse Tyson? What? Well, okay, if birthrate went to zero, then it's not a problem.
1:00:59 Speaker 03 Exactly.
1:01:00 Neil deGrasse Tyson? But who wants that?
1:01:01 Speaker 03 Well, first of all, you're not gonna have complete immortality. You're going to have extended lifespan. So the birthrate simply has to fall in accordance with how much you've increased your lifespan.
1:01:12 Neil deGrasse Tyson? There you go.
1:01:12 Speaker 03 And in fact, if you look at Korea, South Korea.
1:01:16 Neil deGrasse Tyson? It's happening anyway.
1:01:17 Speaker 03 It's happening. People are living longer, and yet the population's going down.
1:01:23 Neil deGrasse Tyson? So Venky, this conversation has been delightful and illuminating and enlightening. I can't wait to die.
1:01:33 Neil deGrasse Tyson? And after we're done with this episode, he's gonna whisper to us that he's 150.
1:01:42 Neil deGrasse Tyson? On this topic of why we die, we covered so many nuances of it. I'm left with very little to offer as a cosmic perspective. What I will say is that, speaking for myself, I, at this stage in my life, value the knowledge that I will die. Because that gives meaning to every day that I'm alive. Knowing that there's one fewer days left in my future. To love, to have new ideas, to make discoveries,
1:02:23 Neil deGrasse Tyson? to embrace all that it is to be alive in this world. If you look at it mathematically, if the knowledge of death is what brings meaning to being alive, then to live forever is to live a life with no meaning at all.
1:02:46 Neil deGrasse Tyson? If you can just put off to tomorrow what you could have done today. Will I think this on my deathbed? If I'm offered a pill that can make me live another 10 years? When I'm on my deathbed, would I take that pill? I don't know. It's kind of easy to talk about death when I'm pretty sure I'm not near it in this moment. But I will say, I reserve the right to revisit the option of living a little longer when I'm on my deathbed. But for now, knowing I'm gonna die is what's keeping me going. And that is a cosmic perspective. Chuck, good to have you, man. Always a pleasure. Gary. Pleasure, my friend. All there.
1:03:30 Neil deGrasse Tyson? This has been StarTalk Special Edition. Topic: Why We Die. Until next time, Neil deGrasse Tyson, your personal astrophysicist. Keep looking up.
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