Researchers have identified a protein which both protects our skin from sun damage and keeps it moisturised. The work, which was partly funded by the EU's Sixth Framework Programme (FP6), has been published online by the journal Nature Cell Biology. Ultraviolet rays from the sun can damage our skin in a number of ways. As well as causing sunburn and damaging our immune system, they can cause skin cancer. According to the International Agency for Research on Cancer, in 2006 there were almost 60,000 cases of melanoma, the most dangerous type of skin cancer, in the EU25, and over 13,000 deaths. This latest piece of research investigates the role of the protein caspase-14 in maintaining the 'stratum corneum', a layer of flattened dead cells that act as a protective barrier for our skin. It is well known that caspase proteins are involved in inflammation processes as well as programmed cell death. However, until now the function of caspase-14, which is concentrated in the skin, had remained unclear. To find out more, the researchers created mice which were unable to produce caspase-14, and compared them with normal mice. The mice lacking the caspase-14 gene had skin that was shiny and wrinkled from dehydration due to the loss of water via the skin. Furthermore, the skin of these mice was highly sensitive to damage from ultraviolet B radiation. Analyses revealed that the composition of the stratum corneum of the mice without caspase-14 was different to that of the normal mice. The researchers found that caspase-14 is responsible for processing filaggrin, which in turn is responsible for aggregating keratin and other proteins in the upper layer of the epidermis to form the stratum corneum. The researchers hope their findings will help the pharmaceutical industry develop new products to protect our skins from the twin threats of moisture loss and UVB damage.
Belgium, United States