Table of Contents
Summarised by Centrist
Scientists are investigating whether cellular rejuvenation could one day treat disease, extend healthy life and possibly reverse aspects of ageing. Susan Dominus reports in The New York Times Magazine that the field is no longer purely speculative, but it remains far from proving full-body age reversal in humans.
The core idea comes from early development. Dominus writes that embryos appear to undergo “natural rejuvenation”, with cells returning to “a kind of ground zero of youth” after conception. Scientists hope to copy part of that process in adult cells.
The research has produced striking lab results. Scientists have restored old human skin cells to a younger state in a dish, rejuvenated diseased mice, strengthened their muscles and turned grey fur black. One 2016 mouse study by Juan Carlos Izpisua Belmonte extended the animals’ lives by 30%. He said: “Aging may not have to proceed in one single direction.”
The main technique involves resetting epigenetic markers, which help tell cells which genes to switch on or off. Shinya Yamanaka’s four “Yamanaka factors” showed cells could be pushed back toward a stem-cell-like state, but the article notes the risk bluntly: “Nobody wants to be a blob of stem cells.”
That risk is central. Earlier mouse experiments caused organ failure and tumours. Some researchers say full use of the Yamanaka factors is not realistic in clinics because “the cancer risks were too high.”
The first human safety trials are now underway, led by Life Biosciences, testing a rejuvenation therapy for glaucoma in up to 18 people. The eye is seen as a more contained target than the whole body.
Scientists disagree on how far the science can go. David Sinclair talks about “age reversal”, while Altos Labs frames its work more narrowly as reversing “disease, injury and the disabilities that occur throughout life.”
Eric Verdin of the Buck Institute warns: “It’s a very different thing to regress a localized disease and to actually revert aging.”
