According to a recent study published in the journal Nature, gray hair may be reversible if melanocyte stem cells (McSCs) are not stuck in one place. The study was led by researchers from New York University's Grossman School of Medicine. These McSCs are responsible for producing the protein that pigments hair, but when they get stuck in the hair follicle bulge compartment, they are unable to generate the necessary protein to produce pigment cells. As a result, hair loses its color and turns gray.
The study was conducted on mice, and it was found that McSCs can move between compartments of developing hair follicles in a healthy state. The different compartments allow McSCs to mature and pick up the necessary protein to regenerate into pigment cells, which continuously color hair as it grows. The McSCs can shift between maturity levels over time as they move between compartments, a unique characteristic of these cells. However, if McSCs get stuck in the hair follicle bulge compartment, they become unable to move back to the germ compartment, where the WNT proteins encourage the cells to regenerate into pigment cells. This leads to the absence of pigment cells, resulting in gray hair.
Mayumi Ito, the senior investigator and professor in the Ronald O. Perelman Department of Dermatology and Department of Cell Biology at NYU Langone Health, explains in a news release that the loss of chameleon-like function in melanocyte stem cells may be responsible for the graying and loss of hair color. She also notes that the motility and reversible differentiation of melanocyte stem cells are crucial in maintaining healthy and colored hair.
The study's findings suggest that if the melanocyte stem cells continue to move or if they can be stimulated to start moving again when stuck, it could lead to more colorful hair worldwide.
According to Qi Sun, a postdoctoral fellow at NYU Langone Health, "Our study contributes to our fundamental understanding of how melanocyte stem cells work to color hair. The newly discovered mechanisms raise the possibility that a similar fixed positioning of melanocyte stem cells may exist in humans. If so, it provides a potential pathway to reverse or prevent gray hair by aiding stuck cells to move again between developing hair follicle compartments."
Sun explains that McSCs are specifically responsible for pigment production and are distinct from the cells responsible for hair growth. As a result, hair can continue to grow even without pigment. The study conducted by NYU revealed that as the hair regrowth process ages, the number of McSCs that become lodged in the follicle bulge increases. At certain points, this non-pigment producing follicle bulge can contain up to 50 percent of all McSCs.
The mobile McSCs that retain their pigment-producing abilities can still create color. However, as the ever-shifting requirements of McSCs break down over time, the increase in gray hair coincides with aging. While stress has also been linked to graying hair, unrelated research conducted by Harvard suggests that stress merely accelerates the hair regrowth pattern, which in turn speeds up the aging process for hair follicles.
The NYU study explains that for unknown reasons, the melanocyte stem cell system fails earlier than other adult stem cell populations, which results in hair graying in most humans and mice.
The next step for the NYU team involves investigating ways to get McSCs moving again once they are stuck, as moving cells produce pigment. This could mean the end of gray hair.
0 Comments