SCIENCE LAB SPECIAL : TURNING GRAY

 

When busy stem cells tire, hair begins to lose its color.

Our hair turns gray when melanin-producing stem cells stop functioning properly. 

A new study in mice, published in the Journal Nature, provides a clearer picture of the Cellular glitches that turn hair gray.

Unlike embryonic stem cells, which develop into all sorts of different organs, adult stem cells have a set path. The melanocyte stem cells in our hair follicles are responsible for producing and maintaining the pigment in our hair.

Each hair follicle keeps immature melanocyte stem cells in storage. When needed, these cells travel from one part of the follicle to another, where proteins stimulate them to mature into pigment-producing cells, giving hair its hue.

The researchers tracked individual cells in mouse fur and found that the stem cells traveled back and forth within the hair follicle, transitioning into and out of their pigment-producing state.

But eventually the stem cells stopped making the journey and thus stopped receiving protein signals to make pigment.

From then on, the new hair growth didn't get its dose of color-producing melanin.

While the study was conducted with rodents, the researchers say their findings should be relevant to humans. [ Kate Golembiewski ]