Stem cell discovery could help stop, or reverse, age-related gray hair.
While gray hair has been increasingly embraced in recent years, it remains a very visible sign of aging that some would prefer not to broadcast. And despite a lot of research into the mechanism that causes melanin-producing stem cells to run out of steam (and therefore the color pigment protein), it’s still somewhat of a, er, gray area.
A breakthrough could be around the corner, with researchers led by a team from NYU Grossman School of Medicine studying these melanocyte stem cells (McSCs) in mice, which humans also possess. They found that the movement of these cells along the hair follicle is key to their transformation and, in turn, their pigmentation. Over time, the system breaks down and they become ‘stuck’ in one spot, unable to evolve into the type of cell that can be coaxed into producing color.
“It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for graying and loss of hair color,” said study senior investigator Mayumi Ito, a professor in the Ronald O. Perelman Department of Dermatology and the Department of Cell Biology at NYU Langone Health.
McSCs show great plasticity as they age and move between different compartments of the developing hair follicle, which expose the McSCs to varying levels of maturity-influencing protein signals.
But as hair ages, sheds and grows back, MCSC numbers swell and they get ‘stuck’ in a compartment called the hair follicle bulge, which prevents them from moving back to their original position – the germ compartment – where WNT proteins would help them develop into pigment cells.