EXPOSURE to sunlight releases a compound from the skin that can alleviate symptoms of eczema, Scottish researchers have found.

The molecule, called nitric oxide, works by dampening inflammation, which causes itchy skin associated with the condition.

Scientists say their findings pave the way for new therapies which mimic the effects of the sun’s rays and could help patients avoid light therapy, which can have damaging side effects on the skin such as raising cancer risk.

Lead researcher Dr Anne Astier, of the Medical Research Council Centre for Inflammation Research at Edinburgh University, said: “Our findings suggest that nitric oxide has powerful anti-inflammatory properties and could offer an alternative drug target for people with eczema.”

Tests on healthy volunteers found that exposing a small patch of skin to UV light triggers a release of nitric oxide into the blood stream.

Further studies found the chemical activates specialised immune cells called regulatory T cells, which act to dampen ongoing inflammation.

The Edinburgh University team found patients with eczema saw the increased number of these cells in their blood following light therapy fitted with disease improvement.

Researchers say their findings could lead to new therapies for the condition, which affects around one in five children and one in 20 adults in the UK.

People with severe forms are often prescribed tanning lamps to help manage their symptoms, but these can cause skin burning, accelerated ageing and increased risk of cancer.

Professor Richard Weller, senior lecturer in dermatology at Edinburgh University, said: “It is clear that the health benefits of sunlight stretch far beyond vitamin D and we are starting to fill in these blank spaces.”

The study is published in the Journal of Allergy and Clinical Immunology.

Last year, scientists at the same university revealed they believe the body’s own natural defences could be used to create a new treatment for a common form of eczema.

Atopic dermatitis, which affects around one in five children and one in 20 adults in the UK, causes chronic and itchy lesions on the face, scalp and limbs as well as broken skin, which makes patients more susceptible to picking up infections.

The team found that sufferers from the condition lack a naturally-occurring protective compound in their skin cells, known as human beta-defensin 2 (hBD2). When hBD2 was applied, scientists discovered it helped the skin to remain intact and strengthened protection.