“New evidence” has been discovered that shows how acute stress can lead to hair going grey prematurely, scientists have claimed.
The research, which was published in the journal Nature, was conducted by a team from Harvard University in Massachusetts, US.
While studying the pain experienced by mice when injected with the toxin resiniferatoxin, they discovered that the subjects’ fur had turned white within a four-week period.
This inspired them to delve further into the role stress plays in causing hair to grey at an accelerated rate.
The scientists exposed the mice to several different kinds of stressors, including pain, psychological stress and restraint.
Each stressor was found to result in a depleted number of melanocyte stem cells (MeSCs).
Melanocyte cells, which can be found on every individual hair follicle, produce the pigment melanin, which determines hair colour.
A person’s supply of MeSCs is reduced over time, thus resulting in their hair going grey or white as they age.
While previous research has shown an association between stress and premature greying, the exact biological mechanism has remained uncertain.
During their study, the Harvard researchers noted that the stress experienced by the mice activated their sympathetic nervous system, which triggered the release of the neurotransmitter noradrenaline.
The team discovered that the release of noradrenaline caused the MeSCs to “move away” from the hair follicles, thus making the hair go grey as a consequence.
Dr Ya-Chieh Hsu, a professor of regenerative biology at Harvard and a senior author on the study, said the study lays “the groundwork for understanding how stress affects other tissues and organs in the body”.
“Understanding how our tissues change under stress is the first critical step towards eventual treatment that can halt or revert the detrimental impact of stress,” Dr Hsu said, adding: “We still have a lot to learn in this area.”
In addition to assessing the impact of the release of the neurotransmitter noradrenaline, the researchers also found that when the mice were exposed to stress in their experiments, a specific gene caused a protein called CDK to encode.
When the mice were injected with a drug which hinders the encoding of CDK, this prevented their fur from turning white.
Dr Thiago Mattar Cunha, a co-author of the study and a researcher with the Centre for Research on Inflammatory Diseases in Sao Paulo, Brazil, explained the significance of this discovery.
“This finding shows that CDK participates in the process and could, therefore, be a therapeutic target,” Dr Cunha stated
“It’s too soon to know whether it will actually become a target some day in clinical practice, but it’s worth exploring further.”
The researchers said that while their findings may not provide a cure for grey hair, it is significant in helping to understand how stress impacts various areas of the body