IFSCC Magazines, 12 (2009) (1) 25–30
Approximately 40% of the population (all skin categories and phototypes) complain of sensitive skin. Sensitive skin is healthy but overresponsive, meaning it reacts faster and more intensely to several parameters including environmental factors such as temperature changes and the sun, use of cosmetic products, and certain medicines. It experiences discomfort, tingling, burning and intolerance to certain types of products, a condition referred to as neurosensitivity characterized by a lower threshold of tolerance. Currently, all of the causes are not known but an increase in the permeability of the stratum corneum and an exaggeration of the nerve response are considered to be involved in the phenomenon of sensitive skin. Lifestyle factors including tobacco, alcohol, stress, fatigue and emotions also have an effect. A new synthetic tetrapeptide, N-acetyl-L-tyrosyl-L-prolyl-L-phenylalanyl-L-phenylalaninamide (Ac-YPFF-NH2), mimicking a natural opioid peptide was developed with the aim to decrease skin nerve ending stimulation. This tetrapeptide was demonstrated in vitro to reduce cutaneous overreactivity by decreasing release of calcitonin gene-related peptide from sensory neurons via an agonist effect on the μ opioid receptors and in vivo to improve the comfort of sensitive skin by decreasing unpleasant sensations and pain induced by heat and capsaicin. This tetrapeptide targeting an exaggerated nerve response helps to relieve sensitive skin by normalizing the tolerance threshold for environmental factors or certain topically applied uncomfortable products or skincare treatments.
Keywords: Calcitonin gene-related peptide, μ opioid receptor, nerve endings, peptide, sensitive skin