Regardless of the multi-billion anti-wrinkles market size and the numerous sales and marketing claims, so far it is said that nothing can prevent the skin from aging- perhaps maybe just long-term religious sunscreen application. Damage from years of UV exposure among other age-related facilitators drains the skin of its stem cells and the process cannot be slowed down or stopped.
But there is hope on the horizon as of April 3rd, 2019 with the published study that provides highlights on how the skin loses its stem cells and its ability to renew them. If further reveals two chemicals that just might be able to prevent the loss.
The study led by a stem cell professor from Tokyo medical and dental university, Emi Nishimura, disclosed that UV exposure and aging play a huge role in stem cell depletion of an important collagen protein. Skin aficionados might be able to identify collagen as key in maintaining skin elasticity, strength, and youthfulness. When damaged cells are no longer able to divide, they are automatically forced to grow old. As more cells become weak, the skin no longer has healthy ones to replace them which leads to having thin skin and wrinkles.
A dermatology professor at Harvard David Fisher says it is an elegant study but will also involve a lot of mechanistic insights and potential actionable practical aspects that promote youthfulness. Our skin is divided into the epidermis and the dermis. The epidermis is what we see on the surface and we perceive as the skin while the underlying dermis consists of hair follicles, sweat glands, connective tissue, and blood vessels.
The top layer of the skin is constantly replaced by the self-replenishing stem-cell pool located at the basal level. The stem cells are connected by tissue to the basement membrane that links the dermis to the epidermis. The key concern of the study is to establish why the body loses more stem cells as we grow older.
The study suggests that cells divide vertically once damaged by toxins as well as the normal aging process. The weak cells have weak roots as well and are unable to strongly attach to the basement membrane. The neighboring healthy cells gang up and push the weak ones to the bottom forcing them to mature.
Biochemistry professor from the University of Colorado, James DeGregori explains that the purge is a quality control measure where damaged stem cells are pushed off the island as if they are all fighting for a position to anchor to the basement membrane.
At first, this kind of competition is healthy because the skin can get rid of malfunctioning, weaker cells keeping wrinkles at bay. Unfortunately with time the weaker cells outnumber the healthy ones and strike an unhealthy balance since the skin cannot automatically rejuvenate effectively.
The linchpin used in this process is collagen 17- critical for rooting stem cells to the membrane. As the cells become weaker they lose collagen 17 protein and therefore lose their grip to the basement membrane and are kicked out by healthy cells.
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