For context, Irina Conboy (the senior author of this work) has been publishing on the concept of tissue regeneration for a long time now, but I think it's a bi

For context, Irina Conboy (the senior author of this work) has been publishing on the concept of tissue regeneration for a long time now, but I think it's a bit of an exaggeration to consider this line of work to constitute a reversal of aging. This New Atlas article alludes to work done in 2005, which was a paper Irina published in Nature [1] while she was a postdoc in Tom Rando's lab. They had joined the circulatory systems of young and old mice, and showed that this process could improve the regeneration of both blood and muscle. Significantly, they had highlighted a cellular pathway, called Notch, which they said was responsible for this effect. In the years since, Irina has focused on the same models -- regeneration of blood and muscle -- but has been looking for a better way than Notch to explain the original findings. It's clear that there are factors in young blood to which some old cells can respond favorably. Importantly, however, none of these measures actually reverse aging in the ways that matter (lengthening telomeres, correcting oxidative damage, etc). Experimental mice treated this way also don't live any longer than usual, except for the very specific cases where you're treating a disorder that would normally shorten their lifespans. 1: https://www.nature.com/articles/nature03260 https://www.nature.com/articles/nature03260