Stress May Make You Itch

Berlin, Germany — Current research suggests that stress may turn on immune cells in your skin, resulting in inflammatory skin disease. The related report by Joachim et al., “Stress-induced Neurogenic Inflammation in Murine Skin Skews Dendritic Cells towards Maturation and Migration: Key role of ICAM-1/LFA-1 interactions,” appears in the November issue of The American Journal of Pathology.

Skin provides the first level of defense to infection, serving not only as a physical barrier, but also as a site for white blood cells to attack invading bacteria and viruses. The immune cells in skin can over-react, however, resulting in inflammatory skin diseases such as eczema and psoriasis.

Psychological stress directly effects skin through the “brain-skin connection”, resulting in common stress-induced responses such as excessive sweating or flushing. In patients suffering from inflammatory skin conditions, stress can either trigger or increase the severity of outbreaks.

Researchers lead by Dr. Petra Arck of Charité, The University of Medicine Berlin, hypothesized that stress could exacerbate skin disease by increasing the number of immune cells in the skin. In order to test this hypothesis, they repeatedly exposed mice to sound stress. Dr. Arck’s group found that exposure to stress resulted in higher numbers of mature white blood cells in the skin. Furthermore, blocking the function of two proteins that attract immune cells to the skin, LFA-1 and ICAM-1, prevented the stress-induced increase in white blood cells.

Taken together, the data from Joachim et al suggest that immune cells may “play a pivotal role in initiating and perpetuating skin inflammation in response to stress.” Future studies will aim to identify how stress turns on immune cells, with the goal of preventing this response in people with chronic skin disease.