Immortality is one step closer, thanks to the work of a team scientists who recently managed to rejuvenate aging mice by causing their overly ripe cells to revert to their embryonic state. While the researchers say they’re still nowhere near ready to trial this sort of thing in humans, their work does at least raise the possibility of a future in which aging – and possibly death – is less than inevitable. As the years go by, the DNA in our cells picks up molecular tags called epigenetic marks, which alter the way that genes are expressed and lead to biological deterioration. By removing these epigenetic tags, therefore, it may be possible to cause our withered chromosomes to return to their original state, undoing the ravages of old age. Using mice that had been bred to suffer from premature aging, the researchers activated four genes – known collectively as the Yamanaka factors – that are normally expressed in embryonic stem cells, in the hope of rejuvenating the mice’s withered cells. Not only did this leave the mice with healthier skin, hearts, and other internal organs, but it also increased their lifespan by more than a third. The team then used the same technique on healthy mice that had been injected with cobra venom, which caused significant damage to their muscle tissue, and found that expression of Yamanaka factors in these mice increased muscle regeneration. Finally, the researchers removed all the insulin-producing cells from the pancreas of another set of mice, and discovered that activating the same four genes caused the animals to replenish these cells much faster than those that didn’t receive the treatment. Describing their work in the journal Cell, the team report that activating this set of four embryonic genes appears to cause mature cells to revert back to stem cells – naïve, innocent and as yet unspoiled by the corruptions of life. If a similar effect can be achieved in humans, then it may actually be possible to one day stop aging in its tracks. Source
