We know today that ageing is a result of several things going on at once. To name a few vectors:
- - Inflammation of the hypothalamus has been correlated to ageing, so we know good communication through all nervous systems (CNS/PSNS/SNS/ANS/PNS) is essential.
- - Therefore we know that chronic desensitization to, and/or reduction of, neurotransmitters, is also a vector for ageing since this vector would make all organs not work optimally.
- - Circadian rhythm that is not "calibrated" can cause chronic damage attributed to ageing (such as the liver doing different circadian operations other than the ones it's supposed to be doing while you're sleeping).
- - Running out of your pool of stem cells.
- - Running out of your telomeres which makes mitosis essentially come to a grinding halt (aka Hayflick limit). This brings us to the next vector:
- - Threshold of senescent:non-senescent cell ratio in any particular organ or tissue is crossed towards being overwhelmingly senescent.
- - etc. etc.
So yes, a high cell turnover rate is one of the ways in which one's body can quickly deteriorate in theory.
Yes; in some circumstances a high turnover rate can be favourable in terms of a tissue or organ as a whole, through the effect of abundance: the younger/less senescent cells will proliferate more-so than senescent ones, and therefore you will remain with more youthful cells while the senescent ones die off without proliferating because all the protein/nutrients will be used up by the more active cells.
In terms of increasing "longevity" of a cell, the closest scientific insight we have for this is the observed/documented effect of "reprogramming" a cell into thinking it's new just like we see in newborn infants (usually by converting the cell back into a stem cell first). So yes, it would be beneficial for sure, though it's still a phenomenon today because this "longevity clock" or "biological clock" mechanism is yet to be fully elucidated/characterized through research.
There are indeed all kinds of pharmaceuticals and nutraceuticals that affect rate of proliferation but without the indication that the drug is meant for anti-ageing; it'd be more of a side-effect. Even food alone affects rates of proliferation. You can search through pathway maps to find which does what. For example: PPAR-delta signaling affects proliferation of skin cells, and arachidonic acid is one of the factors in the pathway map, so peanuts / peanut butter regulate(s) keratinocyte proliferation. etc. etc...
Edited by holdout, 14 July 2014 - 09:51 PM.