As we age, the appearance and structure of our skin changes. This is plain for all to see—we can usually estimate a person’s age simply by looking at their skin. Young skin is full of molecules that keep it thick, plump, and supple, such as collagen and elastin. Over time, the skin produces less and less of the substances. Consequently, aging skin is thinner and it loses its strength and elasticity. As such, the skin develops fine lines and deep wrinkles. It also becomes lax and begins to sag.
Scientists know that the quantity of collagen, elastin, and other proteins make the difference between young and old skin. Not surprisingly, doctors have been trying for decades to increase the levels of these molecules in the skin in an effort to reverse the signs of aging skin. Some approaches work for short periods of time. For example, laser and intense pulsed light treatments can stimulate the skin to produce these youthful molecules. Another approach is to directly inject collagen and other substances into the skin. The Holy Grail of skin rejuvenation, however, is to find a way to make the skin naturally produce more of these substances. Recent research suggests that stem cells could be the answer.
Researchers collected mesenchymal stem cells from umbilical cords. This tissue is removed and discarded after a woman gives birth to a baby. The scientists then collect the tiny sacs called exosomes from these umbilical cord stem cells. Exosomes are densely packed with proteins, RNA, and other important molecules that are important for growth in rejuvenation. The researchers then simply applied these exosomes to samples of human skin to see if they could influence skin rejuvenation.
The first remarkable finding of this research was that exosomes taken from umbilical cord mesenchymal stem cells were absorbed into human skin. Why is this important? Because it means that if exosomes are used as a potential treatment, they can be placed on the skin rather than injected into the skin. The second remarkable finding is that exosomes, once they cross into the skin, are taken up by skin cells (human dermal fibroblasts). Once inside the skin cells, the exosomes take over the cells, in a way. They prompt the cells to produce more collagen and elastin than normal. The exosome-treated skin cells also attract other cells to the skin. We know from other work that more collagen, more elastin, and more cells within the skin leads to plumper, fuller, more elastic skin.
While clinical trials are needed to confirm this research, this work strongly suggests that the exosomes from umbilical cord-derived mesenchymal stem cells have the ability to rejuvenate human skin. Perhaps most impressively, these potential skin rejuvenating exosomes can be applied topically, such as within a cream or ointment. Thus, patients could receive the potential benefits of this treatment, while avoiding painful injections. Again, more work needs to be done before this research becomes a routine treatment, but the results are quite promising.
Reference: Kim, YJ. et al. (2017). Exosomes derived from human umbilical cord blood mesenchymal stem cells stimulate rejuvenation of human skin. Biochemical and Biophysical Research Communications. 2017 Nov 18;493(2):1102-1108.