The stem cell research results could lead to treatment that halts or reverses the process.
Scientists believe they have discovered the mechanism for hair turning gray, which could help develop a treatment to alter cells to reverse or halt the process.
A new study suggests stem cells may get stuck as hair ages and lose their ability to mature and maintain hair color.
Specific stem cells – which can develop into many different cell types – have a unique ability to transition between growth compartments in follicles. These cells lose the ability to move with age, resulting in grayness.
The research focused on cells in the skin of mice and also found in humans, called melanocyte stem cells, or McSCs.
The scientists, led by researchers from New York University Grossman School of Medicine, suggested that if their findings hold for humans, they could open up a potential way to reverse or prevent gray hair.
The study’s lead investigator, Qi Sun, a postdoctoral fellow at NYU Langone Health, said: “The newfound mechanisms raise the possibility that the same fixed-positioning of melanocyte stem cells may exist in humans.
“If so, it presents a potential pathway for reversing or preventing the grain of human hair by helping jammed cells to move again between developing hair follicle compartments.”
Hair color is controlled by whether continually multiplying pools of McSCs within hair follicles get the signal to become mature cells that make the protein pigments responsible for color.
Researchers found that during average hair growth, the cells continually pivot between compartments of the developing hair follicle. In these compartments, McSCs are exposed to signals that influence maturity.
Researchers found that McSCs transform between their most primitive stem cell state and the next stage of their maturation, depending on their location.
According to the findings, as hair ages, sheds, and then repeatedly grows back, increasing numbers of McSCs get stuck in the stem cell compartment called the hair follicle bulge, where they remain.
A senior investigator on the study, Mayumi Ito, said: “It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for grain and loss of hair color.”
SOURCE: THE GUARDIAN