GREY hair could be resigned to history after researchers discovered what may cause the colour to drain as you age.
Stem cells vital for maintaining hair colour become “stuck” as people get older, their study found.
GettyNew York University scientists have found what may cause hairs to turn grey, paving the way for new drugs to reverse colour-loss[/caption]
The finding could pave the way for new treatments aimed at preventing the mechanism from happening, they said.
This could lead to ways of preventing greying — or even reversing it.
Dr Qi Sun, of New York University, said: “Our study adds to our basic understanding of how melanocyte stem cells work to colour hair.
“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 greying of human hair by helping jammed cells to move again between developing hair follicle compartments.”
Hair usually starts to gradually lose its colour from around the age of 35, although this can occur earlier.
Colour is produced at the follicle — a pore around the root of the hair — and once a hair starts to grow, it does not change its colour.
As you age, the follicles become less able to produce pigments, meaning when a hair dies and regrows it comes out grey.
So far, no treatment to prevent this has yet been developed, with people using synthetic hair dyes to prevent greys showing through.
The latest study, published in Nature, looked at how stem cells affect follicles’ ability to keep producing colour.
Researchers tested cells in the skin of mice and also found in humans called melanocyte stem cells, or McSCs.
They found colour is controlled by whether pools of McSCs in follicles get the signal to mature and make protein pigments.
During normal hair growth, such cells continually move back and forth as they transit between compartments of the developing hair follicle.
But 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, preventing colouring.
Professor Mayumi Ito said: “It is the loss of chameleon-like function in melanocyte stem cells that may be responsible for greying and loss of hair colour.
“These findings suggest that melanocyte stem cell motility and reversible differentiation are key to keeping hair healthy and coloured.”