WHY WE DIE: The New Science of Aging and the Search for Immortality
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«Why We Die: The New Science of Aging and the Search for Immortality» is the title of a book by Nobel laureate in Chemistry Venki Ramakrishnan. In 2009, he was awarded the prize for discovering the structure of ribosomes. For many years, Ramakrishnan led the Laboratory of Molecular Biology in Cambridge and the Royal Society in London, striving to unlock the mysteries of aging and death.
In this groundbreaking new study, Ramakrishnan draws some unexpected conclusions. He starts by suggesting that we view aging not as an anomaly but as an inherent part of life. Let’s explore his ideas alongside the authors of Nature magazine, who have dedicated an in-depth article to this scientist’s new book.
WE’VE HIT THE AGE CEILING
We are born, grow, mature, and reproduce. With each passing year, we suffer more from chronic diseases. Eventually, we weaken and die. These are the facts of life. No matter how much we wish otherwise, they are unlikely to change. But perhaps one day, everything will be different for us.
Advances in aging research suggest that death can be postponed — some even believe by hundreds of years. Our fantasies about eternal life are fueled by the invention of cutting-edge anti-aging drugs like analytics. Ramakrishnan tries to assess these hopes and separate fact from fiction soberly.
In the past 100 years, human life expectancy has more than doubled. This was made possible by improved living conditions and innovations in healthcare, particularly antibiotics and vaccines. However, the maximum lifespan has hit its ceiling — 120 years. As we approach that limit, most people inevitably enter a phase where the problems of aging begin to catch up with them.
BROKEN TIME
How can we avoid aging and death? For millennia, this problem has been the subject of speculation, beliefs, and myths. The search for the «elixir of youth» has accompanied humanity throughout history. Modern science, too, has joined this quest.
Aging is what naturally happens to any living organism that survives beyond a specific period. By this time, they’ve typically passed on their genes to the next generation. After that, selective pressure no longer prevents the processes of degradation and decay.
Aging has numerous biological markers: DNA accumulates damage, the ends of chromosomes shorten, proteins clump together, organelles stop functioning correctly, the number of stem cells decreases, and chronic inflammation arises. All of these signs point to increasing chemical damage to molecules.
These «breakdowns» affect virtually every cellular system, including those responsible for maintenance, repair, and regeneration that typically counteract deterioration. This creates a kind of «vicious cycle», initiating cellular aging that inevitably leads to the organism’s death.
UNDERSTANDING WHAT WENT WRONG
Ramakrishnan explains the fundamental processes of aging in language that is accessible even to a lay audience. He believes the main task for researchers is to establish the connections between «everything that has gone wrong».
Is aging caused by a single factor or multiple factors? Which of them is dominant? The scientific community does not have a unified answer. However, most scientists recognize substantial evidence that the ultimate cause is the accumulation of DNA damage. This damage can be caused by a variety of factors, including oxygen radicals, ultraviolet and X-ray radiation, cigarette smoke, chemotherapy drugs, alcohol, many natural metabolites, and even water.
Acknowledging this fact is crucial for identifying reliable biological markers of aging in tissues or blood. Today, these markers can be determined thanks to a groundbreaking scientific discovery — the identification of epigenetic clocks in our genome.
Moreover, this knowledge allows us to target specific processes, potentially enabling us to intervene in the aging process.
THE MAIN SECRET TO A LONG LIFE
Reports about scientific advancements in anti-aging interventions attract public attention, and spark heightened interest from commercial entities. In particular, we’re talking about senolytics — compounds that eliminate aging cells. But there’s one problem with analytics: even scientists themselves aren’t always sure if the research results are reliable. Can they be interpreted as promising, or are they merely preliminary?
Because of this, Ramakrishnan advises against jumping to conclusions. To form an accurate understanding of anti-aging and death-prevention technologies, one must do what few dare: critically assess all literature and consult only trusted experts. Most importantly, rational, independent thinking and common sense should be used.
With this approach, it becomes clear that it’s challenging to add anything new to the list of tips for combating aging. Dietary restriction has long been known to slow aging and significantly extend life. Unfortunately, this practice is unpopular with most people today. The solution may lie in finding drugs that mimic the effects of fasting.
ANALYTICS AREN’T OMNIPOTENT YET
Inhibiting the metabolic enzyme mTOR can extend lifespan, but its effect seems to be limited. A promising alternative could be GLP-1 receptor agonists, which, by reducing appetite and body weight, help treat diabetes and obesity. However, Ramakrishnan’s focus is primarily on senolytics, which have raised overly high expectations among the public.
These drugs show many benefits in mice. However, the situation is far more complex in humans, as cellular aging takes many forms. There are also concerns about the strategy of partially rejuvenating old mice by administering substances derived from the blood of young donors.
Nevertheless, Ramakrishnan views the research on reprogramming adult mouse cells into stem cell-like states as highly promising. Once safety concerns are addressed, such methods could be applied to humans in the distant future.
THE «ELIXIR OF YOUTH» WON’T REPLACE A HEALTHY LIFESTYLE
Ramakrishnan debunks a number of myths found in both scientific and pseudoscientific literature. He notes that the rejuvenation strategy based on cell replacement has a significant limitation: it is not suitable for all tissue types.
Such methods are not appropriate for brain cells, as most neurons must remain alive and functional throughout our lives. While there are protocols for cultivating «mini-brains» — clusters of differentiated neurons — they in no way replicate the vast complexity of real brain tissue.
Ramakrishnan also finds the idea of placing a brain or entire body in liquid nitrogen, waiting for science to resurrect them someday, rather absurd. This, he says, is reminiscent of the ancient Egyptians’ belief that their pharaohs would one day be revived. The Nobel laureate further points out that even his colleagues sometimes fail to distinguish between DNA damage and DNA mutations — the former causes aging, while the latter leads to severe diseases like cancer.
His new book will likely help investors in anti-aging drugs save considerable sums of money. Venki Ramakrishnan reminds us of the futility of chasing after «elixirs of eternal life». It is far more effective to promote a healthy lifestyle and focus on advancing life-extension technologies by intervening in the fundamental aging mechanisms long understood by science.
Original research:
