Researchers Uncover Molecule Responsible for Sunburn Pain

Image courtesy of WebMD

Welcome back to my general dermatology blog. An interesting new breakthrough in sunburn research recently made waves in the scientific community. According to a study published in the Proceedings of the National Academy of Sciences, the red skin developing from sunburn is caused by a molecule called TRPV4. This molecule, which is abundant in the skin’s epidermis, could be blocked to greatly protect against the pain caused by sunburn.

This discovery originated from a collaboration between researchers at Duke University, the University of California-San Francisco, and Rockefeller University’s Laboratory of Mammalian Cell Biology and Development. Rockefeller University researchers discovered TRPV4, an ion channel shown to be involved in other pain processes, more than ten years ago.  Duke’s Wolfgang Liedtke and Rockefeller’s Elaine Fuchs recently began testing the role of TRPV4 in the epidermis by building a mouse model missing TRPV4 in the outermost layer of its skin. The mouse’s hind paws, which most closely resemble human skin, were exposed to UVB rays. According to the researchers, unlike normal mice, the mutant mice showed little tissue injury and sensitivity.

Researchers then uncovered the sequence of events in the pain pathway. They found that UVB exposure on the skin activates TRPV4, which causes an influx of calcium ions into the skin cells, which then brings in endothelin (the molecule causing pain and itching in humans), which causes TRPV4 to send additional calcium into skin cells. Finally, researchers attempted to blow the pain pathway by applying GSK205 (a compound that selectively inhibits TRPV4) to the hind paws of normal mice. After doing so, the mice were resistant to the pain-inducing and skin-disrupting effects of sunburn.

These results seem to suggest that blocking TRPV4 channels could keep the epidermis from communicating with the skin’s sensory neurons and ease pain from sunburn. Additional tests will be necessary, but TRPV4 could be a new target for treating and preventing sunburn. TRPV4 might also potentially combat chronic sun damage such as skin cancer and skin photo-aging. For now, however, make sure you are still wearing sunscreen.

View Rockefeller University’s press release here: http://newswire.rockefeller.edu/2013/08/08/researchers-find-molecule-that-causes-sunburn-pain/

Thanks for reading,

Sudhir Polisetty 

You can learn more about me on LinkedIn or read more of my dermatology blog posts on my Wordpress blog: http://sudhirpolisetty.wordpress.com/