Antiaging comment

A mouse's neurons, when transplanted to an animal with twice the lifespan, lives twice as long only limited by its new host lifespan. The genetic repair and maintenance genes that allow single mouse cells to live twice as long as mice themselves live are present in virtually each and every mouse cell. The difference is one of gene expression, but the mechanisms lie dormant in every cell waiting for a drug or drug combination to unlock their potential.

Even in humans some humans have lived 50+~% longer than average, their neurons with them from birth and mostly identical to the rest of the human population. That same potential to live at least 50+% longer is present in each and every human cell from the entire species. If we go by the neuron transplant, a human neuron might last over two centuries in a longer lived host, and some have speculated that neurons are ageless but succumb to disease due to aging of the supporting glial and vascular cells.

In insects of the same species up to 10 fold difference in lifespan is observed, again between members of the same species. All due to gene expression differences, the same happens within a body at a cellular level, some cells lasting months while others last over 120+years(and could probably last longer if not for host death)

Once again a drug or drug combo could unlock these repair and maintenance mechanisms in the rest of the cells of the body.-source