Peptide TRPV1 Channel Blocker, HCRG21, Effectively Suppresses Inflammation in a Calcipotriol-Induced Allergic Dermatitis Model

As a result of application of hydrogels with 0.05 and 0.005% HCRG21 calcipotriol-induced inflammatory swelling and flaking of the auricle were significantly reduced. As a result of application of hydrogels with 0.05 and 0.005% HCRG21 calcipotriol-induced inflammatory swelling and flaking of the auricle were significantly reduced. Treatment with HCRG21 normalized peripheral blood parameters in mice, including total white blood cell count and basophil percentage. In addition, treatment with gels containing HCRG21 resulted in a decrease in the level of proinflammatory cytokines: interleukin-23 (IL-23) and macrophage-derived chemokine (MDC) by 1.5 and 2 times, respectively, compared to the control group of animals. According to the results of histological analysis of the auricle of mice, treatment with peptide-containing gels enhanced the regeneration of the affected skin area, reducing hyperkeratosis, hyperplasia of the epidermis and dermis, and tissue hypervascularization. Thus, the discovered anti-inflammatory and regenerative effect of HCRG21 in the calcipotriol-induced allergic dermatitis model determines the potential of the peptide as a dermatotropic drug.