A report posted in the journal Science by the Boston-based Dana-Farber Cancer Institute traces the loss of hair colour to the gradual dying off of adult stem cells, called melanocytes, that provide a reservoir for the renewal of pigment-manufacturing cells.
The discovery was made while scientists were researching the origins of malignant melanoma, a potentially deadly form of skin cancer if it is not detected early enough.
Also diminishes shine
The scientific team said that its research showed that the loss of melanocytes not only leads to a greying of the hair, but it also diminishes hues that give the hair shaft a shiny, healthier and more youthful looking appearance.
Melanocytes, which manufacture and store the pigment that combines with hair-making cells called keratinocytes to colour the hair, are specialised cells spawned by colourless melanocyte stem cells.
What actually happens during the greying process is that the melanocyte cells not only become depleted, they also make errors as they age, turning into 'fully committed' pigment cells that position themselves in the wrong part of the hair follicle, thus leading to a loss of pigmentation.
However, although the findings have helped crack the reason why hair follicles actually go through the greying process, the scientific team claims that its research is concentrated on finding how melanocytes proliferate uncontrollably in skin cells to form tumours, rather than pursuing the greying process.
It is not our goal
''Preventing the greying of hair is not our goal,'' emphasises David Fisher, MD, PhD, director of the Dana-Farber Program in Melanoma, and senior author of the Science paper.
''Our goal is to prevent or treat melanoma, and to the extent that this research is revealing the life cycles of melanocytes, which are the cells that become cancerous in melanoma, we would love to identify a signal that would make a melanoma cell stop growing.''
The discovery and the fact that the team will not be pursuing the reasons behind the greying process any further, suggests there might be significant opportunities for cosmetic and personal care researchers to take up where the research has left off, in an effort to make further progress in the field.
This could in turn lead to more effective dyes to cover grey hair, or possibly the discovery of treatments to either reverse or prevent the greying process, although this kind of treatment is still thought to be some way off.
Hair care is rapidly becoming a part of the growing anti-ageing phenomenon as formulators race to include SPFs and a host of restorative ingredients in shampoos, conditioner and styling products. – (Decision News Media, March 2007)