London - Scientists may have found a way of taking the sting out of sunburn.
They have pinpointed the chemical that makes the skin painful and itchy hours after being in the sun.
The discovery could lead to enhanced sun creams that provide extra protection against burning and so reduce the odds of skin cancer.
Most cases of sunburn are caused by the sun’s UVB rays. In moderation, this type of light is beneficial, as it boosts the body’s levels of vitamin B.
But in excess, it damages the skin’s outermost layers, ageing the skin and raising the odds of cancer.
The research, from Duke University in North Carolina, focused on a molecule called TRPV4 which is present in large amounts in the skin’s outer layer.
Using mice and samples of human skin, the scientists showed the chemical to be key to the pain and damage of sunburn.
For instance, mice genetically-engineered to lack TRPV4 in their skin, suffered few effects when exposed to UVB rays.
In contrast, normal mice were extremely sensitive to touch and their skin blistered.
An experimental drug had the same effect.
Applied to the animals’ paws, it blocked TRPV4 from working, and protected the fine skin on the creatures’ paws from UV rays.
Research on human skin samples was also promising, the journal Proceedings of the National Academy of Sciences reports.
The researchers say more work is needed but envisage sun screens containing TRPV4-blockers to protect against burning.
Wolfgang Liedtke, one of the study’s senior authors, said: “I think we should be cautious because we want to see what inhibition of TRPV4 will do to other processes going on in the skin.
“I could imagine it being mixed with traditional sunblock to provide stronger protections against UVB exposure.”
British experts described the research as “very interesting”.
Matt Gass, of the British Association of Dermatologists, said anything that cut the odds of skin cancer would have a “profound impact”.
He added: “Clearly this research is at an early stage, but we would welcome further study into this area to substantiate this suggestion.
“Skin cancer is the most common cancer in the UK, and one of the fastest growing cancers in young people – any progress in helping to prevent it would be an important step.”
The research could also lead to new treatments for other types of pain, including the hard-to-treat pain often suffered by people involved in road accidents.
Dr Liedtke, who works in a pain clinic that treats victims of car crashes and gun shots, said: “We have discovered a novel explanation for why sunburn hurts.
“If we understand sunburn better, we can understand pain better because what plagues my patients day in and day out is what temporarily affects otherwise healthy people who suffer sunburn.” - Daily Mail