[JPLeRouzic]

And some cells do not reproduce (neurons, etc), so you have to keep them in good shape, except this is impossible. For example 1/3 people are infected with Herpes virus which stays in their neurons.

In addition some cells reproduce only a few times, often only during youth.

And there is sometimes involution like in thymus.

[jayGlow]

those cells reproduce at some point, I imagine that if aging can be reversed new cell growth could also be stimulated.

[JPLeRouzic]

> "those cells reproduce at some point,"

No some cells never reproduce, for example motor neurons.

> "I imagine that if aging can be reversed new cell growth could also be stimulated."

I have a hard time to imagine how to replace a up to one meter/yard long cell with sometimes hundred of synapses which is surrounded by cells such as astroglia and microglia that are equally important.