Editor's Note:
This article was translated by the Time School Institute in an interview with Dr. Steven Austad, a renowned scholar in the fight against decay.
Steven Austad is an atypical aging scientist, majoring in English literature, after graduation, he has opened a rental car, worked as a journalist, and worked as a wildlife trainer in Hollywood for several years, returning to school to study biology at the age of 30, but now he is the president of the Foundation for the Preservation of Life for Healthy Aging Research at the University of Alabama at Birmingham, co-principal investigator of the Nathan Shock Center Coordination Center of the National Institute on Aging, and has published 5 monographs and more than 200 academic papers. Covering almost every aspect of the biological aging process from the cellular level to the population level, he became one of the most prominent experts in the field of aging science.
In the interview, Dr. Steven Austad said that he is a big believer in rapamycin and metformin, firmly believing that the combination of drug intervention and a healthy lifestyle is the only way to fight aging; opposing the popular belief that "calorie restriction" can prolong life; and working to find more suitable laboratory animals outside of mice for clinical research... In his eyes, human life expectancy is expected to increase to 150 years!
Original link:
https://www.lifespan.io/news/dr-steven-austad-on-aging-in-wild-and-lab-animals/
Q
As a scientist, your life experience is rich and colorful, how did you finally get involved in the biology of aging?
A
I studied English literature as an undergraduate, wanted to be a novelist, and after repeatedly running into a wall, I recognized reality — I wasn't that piece of material at all. Frustrated, I tried a lot and eventually stayed in Hollywood to train wildlife, I trained lions, tigers, elephants and bears, and so on, and that time revived my interest in biology. Instead of risking my life to study animal behavior, why not go back to campus and do research in a safer and more scientific way?
I only started graduate school in animal behavior at the age of 30, and then turned to longevity research because of a chance opportunity: a possum project during my post-Doctoral period. The project itself has nothing to do with aging, but I found that young, healthy, energetic possums will gradually age in just a few months, suffering from cataracts, muscle atrophy, parasites in the body...
It all happened so fast that I couldn't help but wonder, how quickly the body ages is determined by it. Whether it's a dog, a frog or a bird, how does it grow from a fertilized egg to a healthy, mature body? And why can't this healthy mature body be young forever? It was these questions that opened the door for me to study the biology of aging.
Q
What is your current research topic or research direction?
A
I've always had a topic of interest in which animals are best suited for aging research. I'm working on new animal models, after all, when it comes to mammal research, the first thing that comes to mind in the entire biomedical industry is mice. But there are as many as 5,000 species of mammals, and although mice have their advantages, why are they more researchable, typical or specific than other animals?
For example, metformin generally increases the lifespan of Caenorhabditis elegans, but has no effect on its close relative, the Diplodocus oleraceae. If the response of two closely related nematodes to the same drug is still so different, how much reference value can the results of drug experiments for nematodes be for humans?
Similarly, we don't know if the results of the experiments found in mice have any correlation with humans.
Currently, cancer therapies that work in mice tend to be ineffective in humans, with failure rates as high as 90 percent; more than 300 studies have successfully cured Alzheimer's disease in mice, but so far, these experiments and drugs have had zero success stories in humans. So we do need to include more species (at least two, ideally up to four) in clinical studies to save a lot of time and money spent on human clinical trials.
Illustration: Mouse versus rat
For example, if rapamycin is injected into mice, mice, close relatives rats and distantly related possums at the same time, if they all show little side effects and longer lifespan, then we have reason to believe that the experimental results are transferable, that is, rapamycin has the same life extension effect in humans.
Conversely, if experiments prove that many substances can prolong the lifespan of mice, but none of them are effective for humans, perhaps people will lose confidence in medical anti-aging, thinking that it is impossible to use medicine to intervene in aging and prolong the healthy life and longevity of humans.
Q
You don't seem to agree with the calorie restriction life extension method that is currently popular in the industry?
A
Yes, there are many reasons for this, the most important one being that healthy eating and weight control, while beneficial, don't necessarily prolong life.
From the results of the current research on rodents alone, we do not know whether it is to make obese animals no longer obese to make them healthier, or to make normal-weight animals thinner and thus healthier, in other words, whether abnormally low weight helps to prolong life.
No one can say for sure, after all, two previous monkey studies have come to the opposite conclusion: the researchers let normal-weight monkeys lose weight, and found that there was no effect on survival; in another study, researchers fed monkeys fat, found that many indicators gradually began to be abnormal, and then reduced the weight to normal levels, and found that the indicators were normal again. But this only means that normal weight is good for health, but it does not prove that blind calorie restriction has any life extension effect.
But I think that according to the current experimental results, reasonable fasting, that is, completing the whole day's eating in 12 hours, will be good for prolonging life, that is, the meaning of calorie restriction is not calorie intake, but in the intake time. As long as you stuck the eating time point within 12 hours, you don't have to go on a diet too harshly.
Q
You have previously proposed that there is a hard limit to our human lifespan, about 100 to 120 years, do you think we have a chance to achieve the so-called extreme life extension?
A
Depending on how the "limit" is defined, I think there are indeed limits to human longevity, and unless there are major discoveries and breakthroughs, we won't see anyone who is 200 or 1000 years old. On the other hand, if we delve into human biology, I'm confident that we can extend lifespans by 20 percent.
So I think that human life expectancy is not 80 years, but 100 years. So far, we have achieved this goal in many experimental animals. Frankly, the idea of creating humans who can live 500 or 1,000 years is crazy in my opinion, but a 20% or so life extension is not an out-of-reach goal.
Q
Let's talk about your famous bet with Jay Olshansky. Is the stakes still there? Have the expectations of the two of you changed in some way?
A
Jay Olshansky and I originally made a bet in 2001. We deposit $150 each into one investment account. People born in 2001 will be 150 years old if they live to 2150. If someone does live to be 150 years old by then, then my descendants will get the full savings from the investment account; if not, then his descendants will get all the savings. In 2015, at the urging of journalists, we doubled our bets.
Steven Austad (left) and Jay Olshansky (right)
At the historical growth rate of the stock market, by 2150, the value in the account will be about $1 billion. I'm very confident of winning this bet, and of course he might be very confident because in 2001, when we bet, no one lived past 122. Today, 20 years later, no one still lives past 122.
But on the other hand, I'm focusing on the effects of life extension interventions in all animals. 150 years old is 20% longer than 122 years old, and once an intervention is discovered that can extend human life by 20%, I am likely to win the bet.
But there's another thing that makes me happy: We used to think that to really have a significant impact on longevity, interventions had to start early; but now we're finding out that's not the case, because drugs like rapamycin can still have a significant impact on lifespan when mice started at age 60 or 70.
Once the intervention is in place, perhaps we can start with an intervention in a person's 50s and have them live to be 150 years old. I suspect that ta may be a Japanese woman, because at present women generally live longer than men, and Japanese are the longest-lived human race. In addition, I think that by 2150, human life expectancy can reach one hundred years.
Q
Whether practically or theoretically, what do you think are the most promising anti-aging interventions today?
A
I think gene therapy is outdated. The anti-aging interventions I prefer are combination medications, supplemented by lifestyle interventions.
The reason is that combination drugs can fight each other's side effects. For example, one of the side effects of rapamycin is that it can cause diabetes, and that happens to be the benefit of metformin. I believe that by combining combination drugs with the right lifestyle, the future prospects must be good.
Q
As a veteran of the field of anti-aging, do you think that the population concerned about longevity is still small, the longevity proposition has been misunderstood for a long time, or there is a shortage of funds?
A
At present, many private investors are interested in the longevity field, and the problem of financial constraints will gradually ease. The number of people working on longevity is growing, albeit modestly. But one of the lingering problems in the field of anti-aging is that there are always pseudo-scientists pretending to be experts, after all, 2,000 years ago, there were scammers sitting in the back seat of a carriage selling things like immortal pills and immortal potions.
But at the same time, significant progress is being made in the field of anti-aging: we are indeed gradually understanding the aging process and its internal mechanisms.
More money, more scholars, brighter research avenues, etc. have all given me more confidence, and I think the anti-aging field will be vibrant, continue to evolve, and truly contribute to human longevity in the next few decades.
—— TIMEPIE ——