Although gray hair has become more and more accepted in recent years, it is still a very visible sign of aging that some people don’t want to publicize. Therefore, despite a lot of research being done on chromoproteins, it still seems to be somewhat of a gray area.
A breakthrough may be on the horizon, as researchers led by a team at the NYU Grossman School of Medicine are studying these melanocyte stem cells (McSCs), which humans also harbor, in mice. They found that the movement of these cells along the follicle is key to cellular changes along the follicle and thus pigmentation. Over time, the system breaks down and they become ‘stuck’ in one place, unable to evolve into the types of cells that can be induced to produce color.
“It is possible that loss of the chameleon-like function of melanocyte stem cells is the cause of graying and loss of hair color,” said Ronald O. Perelman, principal investigator at the Department of Dermatology and Cytology. Mayumi said. Biology at NYU Langone Health.
McSCs migrate between different compartments in the developing hair follicle, exposing them to different levels of protein signals that affect maturation, and exhibit great plasticity as they age.
However, as hair ages, sheds and grows back, the number of MCSCs increases and they become ‘stuck’ in a compartment called the follicle bulge, allowing WNT proteins to migrate into the reproductive compartment, the original location to help hair grow. You won’t be able to go back. to pigment cells.
“Our study adds to our basic understanding of how melanocyte stem cells color hair,” said Qi, principal investigator and postdoctoral fellow at NYU Langone Health. Dr Sun said. “The newly discovered mechanism raises the possibility that the same fixed arrangement of melanocyte stem cells also exists in humans. By doing so, we present a potential pathway to reverse or prevent graying of human hair.
Previously, researchers linked WNT signaling and stimulation of mature McSCs to produce pigment. Stem cells ‘attached’ to the follicular bulge compartment, which is located directly above the embryonic compartment, were shown to be trillion-fold less exposed to WNT signaling.
To demonstrate the hair growth-shedding-regrowth cycle, the researchers plucked out the hairs of mice to force them to regrow. What they found was that McSCs packed into follicular bulges increased from 15% to nearly 50% during the forced aging cycle. was. Cells that migrated between compartments, on the other hand, continued to mature and produce pigment over the two-year study period.
Although mouse model findings do not yet provide a rapid solution to age-related gray hair, they pave the way for studies on the movement of McSCs to halt or reverse the process.
“These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and pigmented,” said NYU Langone’s professor of cell biology. Mr Ito said.
Researchers now aim to test the best way to return McSCs to the reproductive compartment to produce pigment once again.
The study was published in a journal Nature.
Source: NYU Grossman School of Medicine
