Multi-Omics Analysis Reveals the Protection of Gasdermin D in Concanavalin A-Induced Autoimmune Hepatitis.

Autoimmune hepatitis (AIH) is a progressive inflammation-associated liver injury. Pyroptosis is a novel inflammatory programmed cell death wherein gasdermin D (GSDMD) serves as the executioner. Our work challenged mice with concanavalin A (ConA) to try to unveil the actual role of GSDMD in AIH. After ConA injection, mice exhibited more severe liver damage characterized by a lower survival rate, more extensive hepatocyte necrosis and apoptosis, and higher serum transaminase levels, indicating the protection of GSDMD in ConA-induced AIH. Furthermore, the mice exhibited higher hepatic expression and serum levels of inflammatory cytokines (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], and interleukin-17A [IL-17A]) and more infiltration of macrophages and neutrophils after ConA treatment than did wild-type (WT) mice. mice with AIH showed increased hepatic l-glutamine levels but decreased glycerophospholipid metabolites levels. L-glutamine levels showed positive correlations while glycerophospholipid metabolites showed negative associations with liver injury indexes and inflammation markers. We further observed a destroyed intestinal barrier in mice after ConA injection as indicated by decreased transcriptional expressions of , , , and . ConA-treated mice also exhibited higher serum LPS binding protein (LBP) concentrations and hepatic and mRNA levels. Further fecal 16S rRNA gene sequencing demonstrated decreased relative abundances of and but increased relative abundances of and in mice with AIH. was negatively correlated with liver injury and inflammation indexes and positively associated with , , and levels. was positively related to liver injury and inflammatory cytokines and negatively correlated with gut barrier indexes. Our study provides the first direct clues to the protective role of gasdermin D (GSDMD) in autoimmune hepatitis (AIH). We demonstrated that knockout exacerbated concanavalin A (ConA)-induced AIH in mice. It may be due to the destroyed intestinal barrier and changes in certain intestinal microbes and hepatic metabolites resulting in increased liver injury and inflammation in ConA-treated mice. This finding suggested a nonnegligible role of GSDMD in AIH and also confirmed its physiological nonpyroptosis effects on the host. The role of GSDMD in autoimmune liver diseases or other liver diseases is complex and intriguing, deserving deep investigation.