Xuanbi Xuanfuhua Decoction intervenes in pulmonary source sepsis in rats by regulating PANapoptosis-related proteins

Xuanbi Xuanfuhua Decoction(XBXFHD), as an empirical formula developed by Professor Xie Sheng, a National Qihuang Scholar, for the treatment of critical and severe respiratory diseases, has demonstrated definite efficacy in pulmonary sepsis, but its mechanism of action requires further investigation. This study explores the intervention effect of XBXFHD on pulmonary sepsis in rats from the perspective of regulating PANapoptosis. A rat model of pulmonary sepsis was successfully established by combined intratracheal injection of lipopolysaccharide (LPS), Staphylococcus aureus, and Escherichia coli, with control and different dosage drug groups established. HE staining, ELISA, Western blot, and flow cytometry were used to evaluate pathological changes in lung tissue, levels of inflammatory factors, cell apoptosis, expression of pan-apoptosis-related proteins (such as Caspase-3, Bcl-2, ZBP1, RIPK1, RIPK3, MLKL), and the proportion of CD4⁺ T cell subsets (Th17 and Treg). The results showed that XBXFHD significantly reduced alveolar inflammatory infiltration, congestion, and lung injury scores (P < 0.05), decreased the wet-to-dry weight ratio of the lungs, and reduced protein exudation in BALF. At the same time, XBXFHD inhibited the expression of Caspase-3, upregulated the expression level of Bcl-2 (P < 0.01), significantly reduced the apoptosis rate (P < 0.01), and downregulated the mRNA and protein levels of pan-apoptosis-related proteins (high-dose drug group P < 0.01). In addition, the formula reduced the proportion of Th17 (P < 0.01), increased the proportion of Treg (P < 0.05), downregulated the levels of pro-inflammatory factors (such as IL-18, IL-1β, TNF-α), and upregulated the levels of anti-inflammatory factors (such as IL-4, IL-10) (P < 0.05). The drug's effects were dose-dependent. These results indicate that XBXFHD improves pulmonary sepsis-related lung injury by inhibiting PANapoptosis-related proteins, regulating the Th17/Treg immune balance, and reducing inflammatory responses, with dose-dependent effects, providing experimental evidence for the clinical application of this formula.