Novel peptide inhibits inflammation by suppressing of protease activated receptor-2

We synthesized and investigated the effects of a novel peptide B, RRFSLLRY as a novel PAR-2 antagonist. Peptide B decreased calcium levels in HaCat cells stimulated with trypsin and PAR-2 activator (SLIGKV) and cytokeratin 14 and PCNA was decreased by peptide B. Peptides B also reduced the expression of inflammatory cytokines such as TNF-α and interleukin-6. Significant increase of oxazolone-induced transepidermal water loss (TEWL) was decreased by the addition of peptide B in hairless mice. These findings suggest that the anti-inflammatory effect of peptide B is due to inhibition of PAR-2 signaling. Skin safety of peptide B was demonstrated by performing MTT assay and human repeated insult patch test. Our findings indicate that peptide B might have potential as an anti-inflammatory agent without irritating skin for use in cosmetics and medical treatment of dermatologic disorders.