Suppression of endothelial cell PANoptosis: qingyi decoction targets the TMAO-HMGB1 pathway to mitigate lung injury in acute pancreatitis rats.

Abstract

Trimethylamine N-oxide (TMAO) is linked to the onset and progression of acute pancreatitis (AP). Qingyi decoction (QYD) is widely used in Chinese hospitals for treating AP and its complications. This study aimed to explore the role and mechanism of QYD in alleviating severe acute pancreatitis-associated lung injury (SAP-ALI) by the modulation of the gut microbiota metabolite TMAO. The composition of the QYD was analysed using LC-MS/MS. A lung injury model in rats with SAP was created with a retrograde injection of 5% sodium taurocholate (STC, 50 mg/kg) into the pancreaticobiliary duct. The effects of exogenous TMAO, 3,3-dimethyl-l-butanol (DMB), and QYD on pulmonary microvascular endothelial barrier damage in SAP rats were assessed by ELISA, haematoxylin and eosin staining, transmission electron microscopy, RT‒qPCR, immunohistochemistry, and Western blot analysis. An in vitro model of TMAO-induced damage in HUVECs and a monocyte‒endothelial cell coculture system were created. RNA sequencing (RNA-seq) was employed to determine the impact of TMAO on the gene expression profile of endothelial cells. RT‒qPCR, Western blotting, flow cytometry, TUNEL assays, PI staining, and immunofluorescence were performed to assess whether TMAO induces endothelial cell PANoptosis and the effects of QYD on this process. The critical role of high mobility group box 1 (HMGB1) was investigated using a rescue experiment. The results demonstrated that QYD significantly alleviated pancreatic inflammation and lung injury in SAP rats, reduced TMAO levels, and effectively inhibited HMGB1-mediated pulmonary endothelial dysfunction during SAP. RNA-seq, scRNA-seq analysis and in vitro experiments confirmed that TMAO induced PANoptosis in endothelial cells. Mechanistically, QYD may exert protective effects on SAP-ALI by suppressing the TMAO-HMGB1 pathway that mediates endothelial cell PANoptosis, suggesting a potential therapeutic strategy for SAP.