NPR recently ran a show interviewing a number of people who have given TED talks relating to aging, among them Aubrey de Grey, cofounder of the SENS Research Foundation and coordinator of rejuvenation research programs, and Cynthia Kenyon, whose work on single gene manipulations that extend nematode longevity back in the 1990s arguably kicked off the modern wave of interest in slowing aging. It makes for interesting listening; you should certainly take a little time and at least look at the transcripts.
In these short interviews you can see illustrated the most important division in the modern work aimed at intervention into the aging process: on the one hand the mainstream approach of altering the operation of metabolism so as to slow down aging, based on traditional drug discovery methodologies, and on the other hand the radical, disruptive approach of repairing the damage caused by the normal operation of metabolism, requiring the development of new biotechnologies. The strategy here is to avoid changing the operation of metabolism, because that is very hard and far too little is known of the important details, but rather periodically clean up the consequences of normal metabolic activity in order to prevent that damage from overwhelming and altering biological systems so as to cause degenerative aging.
As I'm sure all of you know by now, I'm greatly in favor of the latter approach because all the signs suggest it should be far more efficient and effective at extending healthy life spans, not to mention producing actual rejuvenation in the old. You can't greatly help the old by slowing down aging: better technologies are needed. Rejuvenation is needed. You can't bring aging under medical control by working on metabolic alteration to slow aging. Repair is needed, not merely dialing down the pace of new damage.
Have you ever wanted to stay young a little longer and put off aging? This is a dream of the ages, but scientists have for a long time thought this was just never going to be possible. They thought, you know, you just wear out - there's nothing you can do about it, kind of like an old shoe. But if you look at nature, you see that different kinds of animals can have really different life spans. Now, these animals are different from one another because they have different genes. So that suggests that somewhere in these genes, somewhere in the DNA, are genes for aging, genes that allow them to have different life spans. So if there are genes like that then you can imagine that if you could change one of the genes in an experiment, an aging gene, maybe you could slow down aging and extend life span. And if you could do that then you could find the genes for aging, and if they exist, and you can find them then maybe one could eventually do something about it.
You would think to extend the life span of an animal for such a long time, you know, you'd have to kind of go around in a way and fix things or shore them up. You'd have to do something for the skin and something for the intestine, something for the nervous system. You'd have to - it would be really hard because old tissues all look old, but they all have their own separate problems. But what's the big surprise is that there are these systemic or system-wide control circuits that you can tap into. And what happens is that there are circulating factors, factors in the blood that can move through the animal and tell all the tissues to slow down their aging. Not to slow down their movement, but to slow down their aging. The great secret of all this is that, you know, all animals are much more similar to one another than they are different. Worms have muscles, they have nerve cells, they have serotonin, they have acetylcholine, they have all the neurotransmitters we have, the very same ones. So what that means is, you can easily interrogate the genome by making mutations to find genes that control things, things that you didn't even know were controlled, like aging. And there are actually hints that gene changes in humans that mimic the effects of these changes in animals may contribute to exceptional longevity to becoming a centenarian, in a human.
RAZ: And we just heard from Dan Buettner. He's an explorer and a researcher who studies Blue Zones. These are the areas of the world where people live much longer than anywhere in the...
AUBREY DE GREY: Well, let me stop you right there. How much? How much? It's very important to look at the numbers here.
RAZ: Aubrey de Grey would argue the handful of extra years you can get from, say, a Blue-Zone lifestyle is really pretty minor.
DE GREY: People often laugh at the U.S.A. on this kind of thing because the U.S.A. spends far more money per capita on healthcare than any other country in the world.
DE GREY: And yet, if you look at the league table of life expectancy, it comes down in the 40s somewhere - like, 45 or whatever. But then if you look at the actual absolute numbers, the difference in lifespan between the U.S.A. and the number-one country, Japan, guess what it is? Just guess. Go on.
RAZ: I don't know - four years, five years.
DE GREY: Indeed, only four years. So you know - and these Blue Zones, you know, they might get another couple of years, but you know, the numbers are so small that we've got to do something that nobody has today.
RAZ: Aubrey is an Evangelist, probably one of the loudest voices for what might be described as the anti-aging movement. He's one of the leaders of a group called the SENS Research Foundation. It funds research into what he calls rejuvenation biotechnologies.
DE GREY: Which means new medicines that don't yet exist that will be able to repair the various types of molecular and cellular damage that the body does to itself throughout life and that eventually contribute to the ill health of old age.
RAZ: Aubrey basically looks at the human body in the same way he sees any other machine. You keep it oiled. You replace parts. You do preventative maintenance, and the machine can keep going a lot longer than it was ever meant to. So instead of just focusing on, say, a cure for cancer, he wants researchers to channel their energy into finding ways to prevent cancer and other diseases from ever developing in the human body in the first place. And he thinks if we could do that...
DE GREY: Basically, the types of things you could die of at the age of a hundred or 200 would be exactly the same as the types of things that you might die of at the age of 20 or 30.
RAZ: An accident, for example.
DE GREY: Exactly.
RAZ: Alzheimer's, dementia, cancer - these diseases occur because as you age, your body gets damaged. Molecules get damaged. Cells mutate. Junk accumulates in your body. All of this is natural. It happens to everyone. And Aubrey believes that that damage can be grouped into seven different categories, all of which could be prevented or at least slowed down.
DE GREY: So for illustration, let me just talk about one category.
DE GREY: Cell loss - what is cell loss? It's simply cells in a particular organ or tissue dying and not being automatically replaced by the division of other cells. Now, it turns out that that is actually an important contributor to certain aspects of aging - Parkinson's disease, for example. Now, the thing is, we know what the fix for that one is. We know that the right way to repair that kind of damage is stem cell therapy. Now, progress in that area has been patchy over the past 20 years that people have been thinking about this. But now, it's going really well. There are a couple of clinical trials going on. And I'm really optimistic. I think most people are very optimistic. I would say that we've got a very good chance of actually totally curing Parkinson's disease with stem cells in the next 10 years, even.
RAZ: But you're arguing that the right investment in certain scientific research couldn't just get us to a hundred or 110, but it could get us to 110, playing tennis.
DE GREY: That's exactly right - in fact, keeping up with your granddaughter on the dance floor.
RAZ: Is that going to happen?
DE GREY: Well, I've just told you it would. You sound as though you don't quite believe me.
RAZ: I do, but you can understand why it still, today, in 2015, sounds like science fiction, right?
DE GREY: Things that are only - have only a 50 percent chance of happening in 20 years from now are supposed to sound like science fiction.