Turning back the clock is an ideal that many share, yet few realize can actually happen.
Scientists have recently demonstrated that mice can reverse aging through cellular reprogramming. This process involves altering DNA without altering its identity or losing identity over time.
Human trials have demonstrated that interventions such as caloric restriction, plant-based diets, exercise and drugs like metformin can significantly reverse or delay biological aging processes – leading to greater healthspan and longevity for individuals.
How it works
Since Ponce de Leon went in search of his Fountain of Youth, humans have sought ways to turn back time. Although many have found ways to slow aging, turning back time remains an unfulfilled goal; however, new research may provide the means to do just that; at least in mice.
Yamanaka factors transform adult cells back into pluripotent stem cells, enabling them to regenerate into any cell type within the body and regrow after injury or disease. Sinclair and colleagues discovered in their earlier research that injecting these pluripotent genes into damaged retinal ganglion cells of aged mice’ eyes rejuvenated those neurons; more recently Sinclair’s lab has demonstrated it’s possible to rejuvenate muscle, brain and kidney cells as well as rejuvenating an entire mouse’s body!
Scientists have used Yamanaka factors to successfully reprogram cells in test tubes; however, to apply their concept to human beings they have had to iron out some kinks in the process – for instance determining whether the genes responsible for reprogramming also control aging and mutation rates without leading to cancerous proliferation of human cells.
To achieve this goal, they accelerated the rate at which DNA breaks occur during normal cell aging, taking care to ensure most breaks occurred outside the coding regions of genes so as to prevent mutations from arising. At this point in time they activated epigenetic factors to pause gene activity and coordinate repairs; once completed they deactivated them again.
Results
Scientists already possess methods of “reversing aging” in lab mice, while their goal is to develop a pill capable of doing the same for humans. If successful, the implications could be profound: not only would you get back your 20s but you might also be able to treat diseases such as cancer and neurodegenerative conditions more effectively – all thanks to rejuvenation! Bringing back youthful vitality could make all the difference between regretful lives and lives full of promise.
An international team of researchers has discovered how to reverse the signs of aging in mice. Their study shows that breakdown in DNA regulation – or epigenetics – causes mice to age; by restoring this process reversed all signs of aging in them. Their results appear this week in Cell magazine.
Scientists used a high-throughput screening system to search for molecules that can reverse cellular senescence without altering genetic code of cells. After searching extensively for such molecules, six chemical cocktails were identified that successfully reversed it within less than a week, decreasing estimated chronological age by several years without losing cellular identity or leading to any loss of identity in cells.
They conducted an in-vitro real-time genome-wide transcript assay to analyze reprogramming cocktails. Their analysis demonstrated that these treatments reset chromatin structures, restored youthful gene expression patterns and reversed transcriptional signatures associated with senescence. OSK proved particularly powerful at restoring NCCs back to youthful states without altering genome wide transcript profiles or altering transcriptional signatures, effectively reversing all signs of aging without altering cell identity or leading to any loss in cell identity.
Findings suggest that OSK could be an effective strategy for pro-longevity interventions. Other means for reversing cell senescence are also being explored, including using drugs that target JAK-STAT signaling pathways; however, human trials remain years away due to time requirements to test compounds safely and scale them up for clinical use.
Conclusions
Researchers across the world are actively engaged in efforts to reverse aging time and many are optimistic that humans may live longer, healthier lives as a result. Unfortunately, however, the science involved here is complex, so it may take years before definitive treatments for anti-ageing can be developed and tested safely on humans in clinical trials.
Research demonstrates that predicted biological age – an indicator of epigenetic clock ticking- is responsive to various pro-longevity interventions in human and animal models, such as caloric restriction, plant-based diets, recreational physical activity and exercise programs as well as certain drugs (doxazosin for antihypertensive purposes and alpha-ketoglutarate as an alpha-ketoglutarate metabolite) which may decelerate or reverse an individual’s biological age.
Kyoto University scientist Shinya Yamanaka made history when his groundbreaking experiment showed how returning cells back to a pluripotent state with just four genes (OSK) can reverse cellular aging and reset gene expression patterns that had become dysfunctional over time. This discovery has since inspired numerous labs around the world to utilize OSK for reprogramming aged cells and restoring earlier gene expression patterns.
Chemical epigenetic rejuvenation experiments that restore youthful gene expression patterns without altering cell identity suggest that older cells contain information to reset their biological ages in accordance with the Information Theory of Aging. By unlocking and reading this data more efficiently, more effective rejuvenation methods could be developed more rapidly.
Genetic age reversal experiments – in which scientists use gene expression reprogramming techniques to erase all signs of aging from an older animal’s genome – provide further proof that epigenetic mechanisms underlying gene expression reprogramming can indeed reset an organism’s biological age. Furthermore, they demonstrate how chemical reprogramming may partially reverse senescent cell chromatin structures that have become dysfunctional over time.
Darren writes and edits about biology, history, science fiction and more. Based in Portland Oregon with his cat, Darren currently resides there while working on his book about science communication – previously writing for Gizmodo, Paste Magazine and several other publications.
Reversing the effects of aging has long been an intriguing idea in cultures, religions, and sci-fi stories alike. But actually turning back the clock to our 20s? Perhaps scientists — or perhaps one day the Ship of Theseus itself – may one day accomplish that feat.
Bottom Line
At present, it remains too soon to assert that biological age can be reversed; however, scientists are developing methods of countering at least some of the negative consequences associated with growing older.
Anti-aging medicines that actually work will likely take decades before reaching the market; but in the meantime, simple lifestyle adjustments could help extend and improve life span.
If that doesn’t work, there is always the “Ship of Theseus” approach – replacing your biological body with synthetic parts – but this path is best left for sci-fi writers and philosophers, rather than scientists; most practical advice suggests sticking with things such as healthy diet and exercise instead.