During the theory lunch at the Harvard Department of Sytems Biology “Mechanisms of aging and longevity”, Vadim Gladyshev wanted to talk about many projects being done in his lab. But within 1,5-2 hours he only managed to tell about one project, the one I’ve been doing this year in Moscow – when does aging begin, what is the relationship between mortality and aging, and what is the cause of high early life mortality?
The audience was very lively and Vadim was inundated with questions. He also highlighted main theories of aging: aging as a program, mutation accumulation, antagonistic pleiotropy, free radical theory, disposable theory, and hyperfunction/quasi-program as continued development. Marc Kirschner, the founding chair of the Department of Systems Biology at Harvard Medical School, had been sleeping for half of the lecture, but sometimes suddenly woke up and asked questions that made everyone understand that he, as a developmental biologist, adheres to the theory of programmed aging.
Naturally, the aging theory a scientist abides determines what they think about when aging begins. As usual, Vadim asked this questions suggesting several answers: pre-conception, conception ~ -0.75 y.o., birth – 0 y.o., the age of minimal mortality ~ 9 y.o., the onset of puberty ~12-13 y.o., completion of development ~20 y.o., when aging phenotypes manifest – > 30 y.o. As always, all of the answers had their proponents. However, the onset of puberty and age of minimal mortality were chosen by fewer people than usual since there were not many evolutionary biologists at the lecture.
Walter Fontana who used to study aging in worms is not opposed to the damage accumulation theory Vadim proposes, but he only sees the bottom view in it and wants to see the top, i.e. understand how different maintenance mechanisms fail to clear that damage during life and thus cause aging.
After the lecture, I briefly spoke with him about early mortality. He thinks that humans are like cars – very likely to fail during the first months after the assembly but more durable after first tests, so adaptation is the main cause of early mortality. However, he is not sure what would be the best experiment to prove that. But if fact, he said he didn’t really care when aging begins. He just wants to know the mechanisms of aging.
It was interesting that many people are still sure that aging is defined by increased mortality even though there are multiple examples when aging and mortality are distinct in certain species. And the supporting paper with naked mole rats was published just in 2018 and drew a lot of attention.
Leave a Reply