It has been said that aging is “a privilege not given to many,” but gray hair usually comes with that privilege.Gray hair can also be caused by stress, but scientists may be closer to figuring out exactly why even the most colorful hair turns gray with age. A study published April 19 in the journal Nature Certain stem cells have the unique ability to move between the growth compartments of the hair follicle, but as they age they stall and lose their ability to mature and maintain hair color.
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of melanocyte stem cell (McSC) are involved in the generation and maintenance of pigment in hair follicles. All hair follicles store immature melanocyte stem cells, and when needed, the cells migrate from one part of the hair follicle to another. Within these follicle compartments, McSCs are exposed to protein signals that affect varying levels of maturation as a person ages. increase.
according to studywhich McSC mouse cellsas the hair ages, sheds, and then grows repeatedly, more McSCs become trapped in a stem cell compartment called the follicle bulge. Nor can it return to the original location where the WNT protein would have encouraged the regeneration of pigment cells.
“Our study advances our fundamental understanding of how melanocyte stem cells color hair,” said study co-author Qi Sun, a computer engineer at New York University. increase. said in a statement“The newly discovered mechanism raises the possibility that the same fixed arrangement of melanocyte stem cells also exists in humans. We present potential pathways for reversing or preventing graying of human hair.
To learn more about how stem cells behave during different stages of hair growth, the team tracked and imaged individual cells in mouse fur. Not only did the stem cells actually bounce back and forth within the follicle, they transitioned to a mature, pigment-producing state and exited the follicle again as they migrated.
Over time, the McSCs become unable to sustain this process, causing the hair to fall out and grow back, straining the hair follicle. It stopped receiving protein signals. From then on, new hair growth does not get the melanin needed to produce hair color.
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To further investigate this effect, reams plucked hair from mice to stimulate a faster growth cycle. This experiment resulted in an accumulation of McSCs stuck in reservoirs that no longer produced melanin, turning their fur from a dark brown to a unique salt and pepper color.
Co-author Mayumi Ito, a pharmacologist and cell biologist at NYU, said, “Loss of the chameleon-like function of melanocyte stem cells may be responsible for gray hair and hair color loss. said in a statement“These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and pigmented.
The team’s next steps include investigating how to restore the motility of these stem cells back to the pigment-producing compartment.Until then consider Participating in the “Gray Hair Revolution” of people embracing those beautiful gray strands.