Total glucosides of paeony inhibit NLRP3/caspase-1/GSDMD-mediated inflammation and pyroptosis in C3H/HeJ mice with alopecia areata

Abstract

One of the most prominent causes of alopecia areata (AA) is chronic inflammation of the hair follicles. Inhibiting cellular pyroptosis, a form of inflammatory programmed cell death, is crucial for reducing follicular inflammation in the skin. Total glucosides of paeony (TGP) possess anti-inflammatory properties across a broad range of illnesses. However, the role of TGP in AA and its relationship to pyroptosis remain unclear. A chronic unpredictable mild stress (CUMS) approach was used to create an AA mouse model. TGP suspension and MCC950 were administered to AA mice via gavage. HE staining, ELISA, immunohistochemistry, immunofluorescence, RT-qPCR, and Western blotting were performed to detect pathological changes in the skin and investigate the levels of inflammatory factors and pyroptosis-related proteins, as well as the potential mechanisms of TGP’s effects. TGP reduced hair loss, increased the number of hair follicles in skin tissues, and decreased inflammatory markers (IL-6, TNF-α, IL-18, and IL-1β) in AA mice. MCC950 significantly reduced the levels of NLRP3/caspase-1/Gasdermin D (GSDMD)-mediated pyroptosis-related proteins (NLRP3, ASC, caspase-1 p10, and GSDMD-N), as well as inflammatory factors. TGP markedly inhibited NLRP3/caspase-1/GSDMD-mediated cellular pyroptosis in a concentration-dependent manner. TGP suppresses the NLRP3/caspase-1/GSDMD signaling cascade in the skin tissues of AA mice, thereby reducing cellular pyroptosis and inflammation. TGP may be a potential therapeutic agent for AA.