Never can be sure, but if the 2001 article referenced above is correct then resveratrol should cause apoptosis of senescent cells.
The 2017 article that inspired this Longecity thread tested resveratrol in numerous cultures, Resveratrol and its analogues reduced the number of senescent cells, but the experimenters could not find any products of apoptosis produced in their cultures. However, only a limited number of senescent cells in the cultures reversed, and they did not make sure the entire culture was in replicative senescence. This leaves the door open to question whether the cells reversed were in replicative senescence or not. The cells reversed may very well not have been in replicative senescence. This seems probable to me. The cells in replicative senescence have already completed the preliminaries for apoptosis and are waiting for the final step in which nuclear p53 releases cytochrome-c from the mitochondria. This seems difficult to reverse--but who knows?
Review: Senescent cells with functional telomeres but with nuclear damage are maintained in a non-replicative (senescent) state by p53 while waiting for repair. Inhibiting p53 reverts these cells to non senescence. I think there is some evidence that this non-replicative state may also be induced by adjacency to cells in replicative senescence. So I would expect a certain fraction of "senescent" cells to be in this reversible state.
I've read this paper many times and contributed to that thread, and it is my reading that the rejuvenated cells were still proliferation competent (so not yet irreversibly senescent (seen by the fact they were Ki67 positive). What is more interesting is that resveratrol re-elongates telomeres in (near) senescent cells; this is an older paper showing the same is possible in endothelial progenitor cells:
www.ncbi.nlm.nih.gov/pubmed/18587418
The mechanism is likely through the TERT gene becoming available because of the removal of the telomere tail (through shortening). See;
http://journals.plos...al.pbio.2000016
Resveratrol or its analogues then adjust RNA splicing factors (as per the paper you reference; another telomerase repression mechanism) to permit expression of telomerase. Presumably lengthening of the telomere then halts this process because TERT once again is epigenetically suppressed. Only 5uM of resveratrol was required for this to occur (over 24 hours).
Apoptosis of cancer cells took both a greater concentration 25-150uM) and longer exposure (48-72h) to achieve apoptosis in cancer cells, according to this paper:
www.ncbi.nlm.nih.gov/pmc/articles/PMC4337473
It is doubtful we could achieve such concentrations in the blood using resveratrol, though it might be possible with a more bioavailable analogue such as pterostilbene. I have been experimenting with this for some time. In any case, this would suggest resveratrol is not ideal for Turnbuckle's Turning Back the Clocks protocol.
(Could we cross (post this to that thread, moderators?)
Edited by QuestforLife, 31 May 2018 - 02:25 PM.