19 upvotes, 1 direct replies (showing 1)
View submission: Question about Retinol-A and Trentonoin and other Retinoids
Tretinoin user and scientist here, so I can speak from multiple angles.
Telomeres are DNA sequences at the ends of your chromosomes, not proteins. Telomerase is a protein that controls how long the telomeres are. There's no way to tell at what point you telomeres will reach the point of "no return" (called, "replicative senescence"), because it differs across cell types and likely individuals, too.
Your skin is composed of multiple layers, and the layer that's relevant to this discussion is the epidermis. The base of your epidermis contains a layer of stem-like cells. Skin cell "turnover" is regulated by the differentiation of these stem-like cells, which is effectively a maturation process. "Mature" cells in this layer of the skin are known as keratinocytes. At the end of this process, the cells have completely died: they have lost their nuclei, and all that is left is keratin protein. Eventually, this layer is shed/falls off in a process known as desquamation.
Topical retinoids promote differentiation/maturation of keratinocytes in the upper layer of your skin, speeding up desquamation/shedding. (I'm not sure if it directly affects the stem cells, too.) In the case of acne patients, for example, this helps to expel acne blemishes more quickly then would otherwise occur. In this context, I think retinoids also reduce inflammation. From an aging perspective, retinoids promote collagen deposition and vascularization of the skin (improving blood flow), effectively making our skin more elastic and "youthful" looking. (I'm not sure though if these outcomes are related to the effects on cell turnover or if they are biologically unrelated effects.)
Eventually, topical retinoids will start to lose their effectiveness, because biology will take over, so to speak. However, these are all very gradual processes that occur over decades, so you won't wake up in say, five years, and suddenly find that they no longer work, especially if you're only 29. (I am 30 and they still work amazingly for me.) Ultimately, retinoids can slow down the *effects* of aging, but they can't stop such a complex, multi-faceted process.
Edit = clarity.
Comment by q-ka at 27/12/2021 at 15:49 UTC
2 upvotes, 1 direct replies
Interesting as hell thanks for filling the gaps in my knowledge…. So for clarity there’s no worry that in using them that it will accelerate the point at which deep wrinkling will occur, for the luxury of no light wrinkles and age marks now and for the next X amount of years ??? Correct?
If I understand correctly there will just be a point where you reach that age where your body starts to degrade faster and faster and speed of desquamation wont assist in plumper skin and reduced aging signs ?