Baicalin inhibits monosodium urate crystal‐induced pyroptosis in renal tubular epithelial cell line through Panx‐1/P2X7 pathways: Molecular docking, molecular dynamics, and in vitro experiments

Abstract Pyroptosis is a programmed cell death process that frequently occurs in many diseases, including hyperuricemic nephropathy (HN). In HN, a range of stimuli mediates inflammation, leading to the activation of inflammasomes and the production of gasdermin D (GSDMD). Baicalin (BA), a natural flavonoid renowned for its antioxidant and anti‐inflammatory properties, was investigated for its role in HN in this study. Initially, HN‐like inflammation and pyroptosis were induced in HK‐2 cells with treatment of monosodium urate (MSU), followed by the BA treatment. The expression of pyroptosis‐associated genes, Panx‐1 and P2X7, at both mRNA and protein levels was assessed through real‐time polymerase chain reaction (RT‐qPCR) and Western blotting (WB) without or with BA treatment. The results showed that expression of Panx‐1 and P2X7 at mRNA and protein levels was increased in MSU‐treated HK‐2 cells, which subsequently decreased upon the BA treatment. Further experiments showed that BA could combine NLRP3 inflammasome and GSDMD, destabilizing GSDMD protein. Moreover, BA protected the cell membrane from MSU‐induced damage, as evidenced by Hoechst 33342 and PI double staining, lactate dehydrogenase (LDH) assays, and electron microscopy observations. These results suggest that BA is involved in the regulating Panx‐1/P2X7 pathways and thus inhibits pyroptosis, highlighting its potential therapeutic effect for HN.