Michio Kaku is a futurist, popularizer of science, and theoretical physicist, as well as a bestselling author and the host of two radio programs. He is the co-founder of string field theory (a branch of string theory), and continues Einstein’s search to unite the four fundamental forces of nature into one unified theory. He holds the Henry Semat Chair and Professorship in theoretical physics and a joint appointment at City College of New York and the Graduate Center of C.U.N.Y. He is also a visiting professor at the Institute for Advanced Study in Princeton and is a Fellow of the American Physical Society.
Kaku launched his Big Think blog, "Dr. Kaku's Universe," in March 2010.
Question: Do you think the enzyme Telomerase could be used to reverse the aging process in our lifetime? (Submitted by Paul Cellura)
Michio Kaku: Paul, Telomerase hit the headlines; however, I think we have to put it into perspective. It is not the fountain of youth; however, it is a significant breakthrough. We have to put it into a much larger perspective.
First of all, we know that DNA is sort of like a shoelace. It has plastic tips at the end. Every time a cell reproduces, the tips get shorter and shorter and shorter until finally they fray. And you know that your shoelace, without the plastic tips will simply fall apart. That’s what happens inside a cell. A cell, for example, your skin cell, will divide about 60 times, that’s called a Hayflick Limit. Then the cell goes into senescence and eventually dies.
So in some sense, every cell has a biological clock. It is doomed to die after about 60 reproductions. However, Telomerase can eliminate some of the contraction of the chromosomes and the chromosomes can maintain their length. So at first you may say, “ah-ha! We can now defeat the biological clock.” But not so fast, first of all, cancer cells also use Telomerase. Cancer cells are immortal. Cancer cells are immortal and that’s precisely why they kill you. Why are cancer cells so dangerous? Because they are immortal. They grow and they grow and they grow until they take over huge chunks of your body, meaning that your bodily functions cannot be performed and you die. So we have to make sure that when you hit ordinary cells with Telomerase that you don’t also trigger cancer in the process.
Now, also you have to realize that genes are also very essential for the aging process. It turns out that we know what aging is. Aging is the buildup of error. That’s all aging is. The build up of genetic and cellular error. And cells begin to age; they begin to get sluggish because genetic mistakes start to build up. Now cells; however, have a repair mechanism. They can repair damage to their cells; otherwise we would all basically rot very soon after birth. However, even the repair mechanisms eventually get gummed up and then the cell really starts to get old as a consequence. So then the question is, can you accelerate cell repair? That is another branch of gerontology which is being looked at using genes and using chemicals to accelerate the repair mechanisms.
For example, if I take any organism on the planet Earth from yeast cells to spiders, insects, rabbits, dogs, and even monkeys now. And I reduce their caloric intake by 30%, they live 30% longer. In fact the only organism which has not yet been deliberately tested by scientists are homo sapiens. All the other species obey this basic rule. You starve them to death, they live longer. This is independent of Telomerase. This is a function of the wear and tear that we have on the cells. And this is the only known way of actually deliberately extending the lifespan of any organisms almost at will.
Now, what we want is a genetic way of mimicking this mechanism without having to starve yourself because how many people do you know would be willing to starve themselves in order to live 30% longer? Not too many. So then the question is, are there genes that control this process. And the answer is apparently, yes. There’s something called the Sirtuin genes, Sir2 being the most prominent of them. They in turn stimulate certain enzymes, among them Resveratrol, which is found in red wine, for example. So this does not mean that drinking red wine or taking Telomerase is the fountain of youth. I don’t think that anyone has the fountain of youth yet. What I am saying is, we are now finding pieces of the fountain of youth, tantalizing clues that mean that perhaps in the coming decades, we might be able to actually unravel the aging process. We don’t have it yet. Don’t go out to the drug store and stock up on these kinds of chemicals and enzymes thinking you’re going to live forever. However it is conceivable that in the coming decades we’ll come very close to finding it.