Senescent cells, so called because of the role they play in the aging process, have acquired a bit of a bad reputation.
Yet new research from the Buck Institute suggests that these cells may not be so bad after all.
Reporting in today’s issue of Developmental Cell, Buck Institute scientists have found that, while senescent cells do indeed contribute to cellular aging and age-related diseases, they also play an important role in healing wounds. Furthermore, the team has identified the specific molecule in senescent cells that does the healing—pointing to a new therapy that could harness the good aspects of senescent cells, while flushing out the bad.
As we age, so do our cells. During cellular senescence, cells begin to lose their ability to grow and divide. The number of so-called senescent cells accumulates over time, releasing molecules thought to contribute to aging and age-related diseases such as arthritis and some forms of cancer.
But experiments led by Buck Institute Professor Judith Campisi and postdoctoral fellow Marco Demaria revealed that following a skin wound, cells that produce collagen and that line the blood vessels become senescent, and lose the ability to divide. Instead, they accelerate wound healing by secreting a growth factor called PDGF-AA. And once the wound was healed, the cells lost their senescence and shifted back into their normal state.
Because cellular senescence has long been linked to aging and age-related diseases, some research has been focused on finding ways to flush out senescent cells entirely. But the findings by the Buck Institute team throw a wrench in that idea, by revealing that these cells do in fact serve an important purpose.
According to Campisi, there is still a lot to learn:
“It is essential that we understand the full impact of senescence. The possibility of eliminating senescent cells holds great promise and is one of the most exciting avenues currently being explored in efforts to extend healthspan. This study shows that we can likely harness the positive aspects of senescence to ensure that future treatments truly do no harm.”