Plasma from Young Pigs Halves Old Rats' Epigenetic Age
lifespan.io
lifespan.io
That said, this is the output of a very interesting experiment that ran through the Covid period. Katcher believes that they identified blood exosomes (called by the abbreviation E5) as an important factor in relative youthfulness of tissues and organs, and that this mechanism is fairly conserved in mammal species.
Interestingly, a wholy different lab, working in cardiology, confirmed last year (again, in rats), that exosomes from young animals heal old rats' hearts. [0]
Of course it is too early to say that exosomes are a fountain of youth for humans, but the results seem very interesting and the science behind them rigorous.
Katcher himself, who turns 80 this year, experimented with E5 in topical form on the back of his right hand. Left hand was left alone as a "control" of sorts. The difference is quite visible [1].