A recent study led by the University of California, Irvine, has revealed that senescent pigment cells in skin moles can actually stimulate robust hair growth, challenging the previous belief that these cells hinder regeneration. The findings of the study, published in the journal Nature, may provide a roadmap for the development of new therapies for androgenetic alopecia, a common form of hair loss in both men and women.
The research focused on understanding the role of molecules called osteopontin and CD44 in activating hair growth within hairy skin moles, known as nevi. Despite accumulating large numbers of senescent pigment cells, these nevi displayed strong hair growth.
Androgenetic alopecia, commonly known as male or female pattern baldness, is a genetic condition characterized by progressive hair follicle thinning, resulting in the production of finer and shorter hair strands over time. Men typically experience receding hairlines and balding on the top of the head, while women often have overall hair thinning, particularly at the crown.
The study found that senescent pigment cells in nevi produce high levels of a signaling molecule called osteopontin. This molecule triggers dormant and small hair follicles to activate their stem cells, leading to robust growth of long and thick hair strands. The research challenges the notion that senescent cells are solely detrimental to regeneration and aging, highlighting the positive aspect of cellular senescence.
Hair follicle growth is regulated by the activation of stem cells, which divide and enable follicles to generate new hair in a cyclical manner. Following each growth phase, there is a dormant period during which the follicle’s stem cells remain inactive until the next cycle begins.
The findings of this study open up new possibilities for developing targeted molecular therapies that leverage the role of osteopontin and CD44 in promoting hair growth. While further research is needed, this discovery provides valuable insights into the mechanisms underlying hair growth and may pave the way for more effective treatments for androgenetic alopecia in the future.