New sunscreen compound protects against UVA-induced skin aging, cancer

July 21, 2016

While ultraviolet A radiation in sunlight can cause significant harm to the skin, the majority of sunscreens on the market offer limited protection against such damage. But this could change; researchers have identified a compound that they say can shield against ultraviolet A-induced cell damage, skin aging, and skin cancer

Dr. Charareh Pourzand, of the Department of Pharmacy and Pharmacology at the University of Bath, United Kingdom, and colleagues say they hope the compound can be added to sunscreens and other skin care products within 3-4 years.

According to the Skin Cancer Foundation, ultraviolet A (UVA) radiation makes up around 95 percent of the UV radiation that reaches the Earth's surface.

UVA radiation is less intense than ultraviolet B (UVB) radiation, which is the primary cause of sunburn. However, UVA penetrates the skin more deeply than UVB, and it is considered the dominant tanning ray.

UVA radiation - whether from sunlight or tanning booths - penetrates cells in the dermis layer of skin, damaging the collagen fibers, which contributes to wrinkles and liver spots. UVA rays also damage the skin's DNA, which can trigger mutations that lead to skin cancer.

Dr. Pourzand and colleagues explain that UVA rays stimulate excess free iron present in mitochondria, which are structures that produce energy for cells.

This free iron stimulation fuels the production of reactive oxygen species (ROS), which cause damage to cell components - including DNA and proteins - and raise the risk of cell death, skin aging, and skin cancer.

"The role of iron-mediated damage induced upon exposure of skin cells to UVA has been underestimated for many years," notes Dr. Pourzand. "For efficient protection against UVA-induced iron damage of skin, strong chelators are needed, but until now these risked toxic effects caused by non-targeted iron starvation of cells."

'Mitoiron claw' prevented UVA-induced skin cell death

In the Journal of Investigative Dermatology, the researchers describe the development of a compound that can prevent the free iron in mitochondria from reacting to UVA radiation.

Referred to as "mitoiron claw," the newly created compound travels to mitochondria within cells, where it binds to the excess free iron.

For their study, the researchers applied the compound to human skin fibroblast cells and exposed them to 140 minutes of continuous, sea-level UVA radiation.

Unlike untreated skin cells, those treated with the mitoiron claw compound were highly protected against cell damage and death.

Based on their results, the researchers believe the mitoiron claw compound can offer significant protection against UVA radiation.

What is more, they call for the compound to be added to sunscreen and other skin care products - something they hope will occur in the next 3-4 years.

"Our mitochondria-targeted compound [...] can address an unmet need in the skin care and sunscreen fields. This mitoiron claw is a highly effective compound, offering unprecedented protection against UVA-induced mitochondrial damage." Dr. Charareh Pourzand

As well as further investigating the mitoiron claw for its protective effects against UVA-induced cell damage, the team plans to assess whether the compound might be effective against diseases fueled by excess iron in mitochondria, such as Friedreich's ataxia.

http://www.medicalnewstoday.com/articles/311820.php