Scientists are making great strides toward slowing the aging process, but still have much work ahead.
Scientists have achieved impressive success using mice. By mixing blood from young and old animals, scientists were able to inject old animals with fresh cells from younger ones.
Scientists then reversed its epigenome – which comprises chemicals that regulate gene expression – and used this knowledge to make its cells appear younger.
What is aging?
The science of aging is still in its infancy; as a field, it only recently received its due attention. Prior to this point, aging was simply accepted as part of life; an inevitable gradual progression from youthful health through frailty and disease until death finally claimed our bodies. Thanks to this paradigm shift, scientists now possess a deeper knowledge of its processes that lead to it as well as potential causes.
One of the main theories of aging is that it occurs as a result of biological byproducts known as free radicals, produced as part of cell metabolism. If these chemical compounds build up in your body, they can damage DNA and proteins leading to an acceleration in biological aging processes that will ultimately accelerate with age.
There are various strategies available for manipulation to reduce or even reverse aging in humans. Researchers have discovered that their bodies produce new cells more slowly to replace old ones while simultaneously repairing damaged proteins; this approach has only proven successful with mice thus far and its safety and efficacy may still need further study before being applied to humans.
Other researchers have attempted to reset the genes that control aging. By exposing mice to four Yamanaka factors known to restore youthful genes, some researchers have been successful at turning back time and turning off clocks in mice. Unfortunately, however, their experiments were not as fruitful as some had anticipated and have even led to tumor formation in some instances.
Even in spite of setbacks, many remain hopeful about the future of aging research. Some have even gambled their money on anti-ageing products like supplements purporting to lengthen telomeres and slow cellular aging.
While searching for the Fountain of Youth can be an exhausting scientific pursuit, it is also crucial to keep in mind the moral questions at play in its search. Even if immortality were scientifically feasible, would we pursue it anyway? Vadim Gladyshev from Harvard University’s Center on Aging has written extensively on these ethical concerns in his book published this past summer.
How does aging occur?
Human aging is caused by both intrinsic and extrinsic factors. Intrinsic aging occurs within cells, the building blocks of our bodies. Over time, as cells divide, damage accumulates that renders them less healthy or inoperable and leads to cell death or breakdown, leading to cell aging. Extrinsic factors include environment, diet, stress levels and lifestyle habits which all play a part in how quickly humans age.
Scientists have studied the causes of aging for decades, and currently there are various theories as to why we age. One theory, called the programmed theory, suggests that certain genes turn on and off over time to cause our cells to age; another theory, known as the endocrine theory, indicates how hormones play a role by altering cell growth and repair processes; while finally the cellular theory proposes that genetic and environmental factors combined together cause our bodies to age over time.
Scientists recently unveiled an exciting discovery, showing they can use mice and human cells alike to reverse the aging process and thus possibly slowing or even reversing many diseases of aging, such as cancer and cardiovascular disease.
Sinclair led a team that found a way to reconfigure cells’ backup copies of epigenetic instructions, eliminating corrupt signals that cause premature aging. They did so using a drug that cuts DNA at 20 locations throughout their genome before quickly repairing it – mice receiving this treatment experienced dramatic improvements in cell health as well as acting younger than expected compared to biological age.
Sinclair lab researchers decided to attempt reverting adult skin cells back into embryonic or pluripotent stem cells by genetically adding three of four Yamanaka factors into a harmless virus, then injecting this virus directly into damaged retinal ganglion cells at the back of mouse eyes; within days these injected cells rejuvenated themselves by producing new axons reaching deeper into its brain.
Sinclair and his colleagues have employed this technique to reverse aging in muscle and brain cells, including rejuvenating neurons in mice’s brains to extend memory retention and learning capabilities. His lab has demonstrated this effect.
How can science reverse aging?
Rewinding time has long been an aspiration of humanity’s, evident in myths and religions around the globe as well as numerous films and fiction works. Reversing aging has proven difficult through scientific inquiry – however scientists continue their efforts in an attempt to reverse aging; recent findings may make a big impactful statement about human health!
Over the past decade, research on aging has flourished to an extraordinary degree with billions being invested globally in this research field. But one key challenge remains: developing means to halt cell aging without killing it or turning into cancer cells. One promising solution may lie with stem cells known as Induced Pluripotent Stem (iPS) cells; researchers recently conducted groundbreaking work that showed this method can reprogramme these cells back into a youthful state.
Kyoto University biologist Shinya Yamanaka won the Nobel Prize for his groundbreaking experiment that demonstrated how four factors can transform adult cells back into pluripotent stem cells – cells capable of forming any cell in the body – through just four factors. He used these cells to treat progeria, or premature aging. As a result, rejuvenated mice lived longer lives with improved eyesight.
Scientists have since used this technique on various parts of the body. Sinclair’s lab used this approach by injecting three Yamanaka factors into a harmless virus which targeted retinal ganglion cells in mouse eyes – revitalizing them to improve vision while stimulating new connections between brain neurons.
Altos Biopharma, one company working on this issue, plans to create a drug that would stimulate iPS cells to mature more quickly and reduce the risk of diseases associated with age such as Alzheimer’s or heart disease.
Tony Wyss-Coray from Stanford Neuroscience has conducted experiments using parabiosis – injecting older mice with blood from young animals- to rejuvenate their brains and prevent age-related mental declines. By creating new neural circuitry supporting memory and learning processes he hopes that parabiosis will spur.
What are the risks of reversing aging?
Legends have long spoken of a Fountain of Youth and humans have long dreamed of slowing or even reversing aging. Now scientists may have finally made progress towards turning back time – rejuvenating worn out organs in aged mice to make them act younger again.
These new findings mark a landmark achievement in biogerontology, raising hope that diseases related to aging may one day be treatable while remaining symptoms of a larger problem that hasn’t yet been addressed. At present, researchers only seek solutions for individual ailments like heart disease or Alzheimer’s but don’t address what leads up to those conditions – the aging process itself remains unknown and untreated.
Scientists have several options available to them when it comes to combatting aging, all centered on altering cellular signaling pathways. Some studies attempt to replicate the anti-ageing effects of caloric restriction; other projects focus on undoing mutations which accumulate over time and disrupt normal cell functioning; but perhaps most excitingly is something called “cellular reprogramming,” where scientists take fully developed cells and use genetic resetting technology to restart their development.
Researchers have succeeded in reverse aging the laboratory animal Caenorhabditis elegans, and are working on ways to implement it with other species such as mice, monkeys, and primates. Furthermore, researchers are exploring whether human reverse aging is even possible and, if so, what method they could employ to accomplish it.
Reversing aging research may generate considerable buzz, yet scientists not involved with those studies caution that any claims of making someone younger are premature. New work with mice relies on reprogramming genes to reverse epigenetic changes that accompany age, but that does not amount to returning someone back to embryonic stage zero.
Researchers have made progress toward decelerating aging in mice through rejuvenating organs, but even so have seen them succumb to age-related diseases and die. So while decelerated aging should be pursued as an ideal, we must also think through what this might mean in terms of turning back time for people, making them younger, healthier, and free from risk of disability and disease.
