Scientists discover mechanism behind changing colour of skin and hair

Vitiligo, the most common type of skin pigment disorder, affects about 1% of the population. The disorder causes disfiguration and is “marked by the loss of skin pigmentation, leaving a blotchy, white appearance.” New research conducted by a team at NYU Langone Medical Center indicates a possible treatment for these diseases.  

The cells responsible for skin and hair pigmentation are known as melanocyte stem cells. They are highly regulated by cell signaling, part of the endothelin receptor type B (EdnrB) and the Wnt signaling pathways. For the first time, these scientists have been able to investigate the regeneration properties of these cells.  

To analyze the exact effects of EdnrB and Wnt signaling pathways, scientists used mice that were bred to be deficient in the EdnrB pathway. These mice exhibited premature grey hair. Through stimulation of the EdnrB pathway, scientists were able to increase the amount of melanocyte stem cell pigment production by 15 times. After this, the mice’s initially white skin became dark. 

The Wnt component was also determined to be crucial. When this component was blocked in tests with mice, test subjects exhibited “stalled stem cell growth and the maturing of stem cells into normally functioning melanocytes.” The resulting mice were greyish in colour, exhibiting a lack of pigment.  

The NYU team plans to continue studies on this matter, to discover how they can exploit these cells to force regeneration and thus a natural change in the colour of the skin/hair it is associated with. Such a development could allow us to solve many different types of pigment disorders.