Washington: A new research has found that processes that age and damage skin are impeded by dilute bleach solution.
The study was conducted on mice by researchers at the Stanford University School of Medicine, but if shown to work similarly in humans, the inexpensive, widely available household chemical could provide a new way to treat skin damage caused by radiation therapy, excess sun exposure or aging.
Thomas Leung, MD, PhD, an instructor in dermatology at Stanford and a pediatric dermatologist at Lucile Packard Children's Hospital and his colleagues knew that many skin disorders, including eczema and radiation dermatitis, have an inflammatory component. When the skin is damaged, immune cells rush to the site of the injury to protect against infection. Because inflammation itself can be harmful if it spirals out of control, the researchers wondered if the bleach (sodium hypochlorite) solution somehow played a role in blocking this response.
To find out, they homed in on a molecule called nuclear factor kappa-light-chain-enhancer of activated B cells, or NF-kB, which is known to play a critical role in inflammation, aging and response to radiation.
When activated by signalling molecules, it enters the cell's nucleus and binds to DNA to control gene expression. When inactive, it is sequestered in the cytoplasm, away from the DNA.
Leung wondered if there could be a link between the effect of the dilute bleach solution and NF-kB's role in skin. He exposed human keratinocytes, or skin cells, to 0.005 percent bleach for one hour before treating them with a signaling molecule that normally activates NF-kB function.
He found that exposure to the solution blocked the expression of two genes known to be regulated by NF-kB. The effect was reversible, however - waiting 24 hours after the bleach treatment restored NF-kB's ability to activate expression of the target genes.
Leung and his colleagues tested the effect of daily, 30-minute baths in bleach solution on laboratory mice with radiation dermatitis. They found that the animals bathed in the bleach solution experienced less severe skin damage and better healing and hair regrowth than animals bathed in water.
The study is published in the Journal of Clinical Investigation.