In recent years, hypersensitivity reactions to the Shuanghuanglian injection have attracted broad attention. However, the componential chief culprits inducing the reactions and the underlying mechanisms involved have not been completely defined. In this study, we used a combination of approaches based on the mouse model, human umbilical vein endothelial cell monolayer, real-time cellular monitoring, immunoblot analysis, pharmacological inhibition, and molecular docking. We demonstrated that forsythoside A and forsythoside B contributed to Shuanghuanglian injection-induced pseudoallergic reactions through activation of the RhoA/ROCK signaling pathway. Forsythoside A and forsythoside B could trigger dose-dependent vascular leakage in mice. Moreover, forsythoside A and forsythoside B slightly elicited mast cell degranulation. Correspondingly, treatment with forsythoside A and forsythoside B disrupted the endothelial barrier and augmented the expression of GTP-RhoA, p-MYPT1, and p-MLC2 in a concentration-dependent manner. Additionally, the ROCK inhibitor effectively alleviated forsythoside A/forsythoside B-induced hyperpermeability in both the endothelial cells and mice. Similar responses were not observed in the forsythoside E-treated animals and cells. These differences may be related to the potential of the tested compounds to react with RhoA-GTPγS and form stable interactions. This study innovatively revealed that some forsythosides may cause vascular leakage, and therefore, limiting their contents in injections should be considered.
Influenza A virus (IAV) infection triggers excessive activation of PANoptosis—a coordinated form of programmed cell death integrating pyroptosis, apoptosis, and necroptosis—which contributes to severe immunopathology and acute lung injury. However, the molecular regulators that drive PANoptosis during IAV infection remain poorly understood. In this study, we integrated bulk and single-cell RNA sequencing (scRNA-seq) datasets to dissect the cellular heterogeneity and transcriptional dynamics of PANoptosis in the influenza-infected lung. PANoptosis-related gene activity was quantified using the AUCell, ssGSEA, and AddModuleScore algorithms. Machine learning approaches, including Support Vector Machine (SVM), Random Forest (RF), and Least Absolute Shrinkage and Selection Operator (LASSO) regression, were employed to identify key regulatory genes. scRNA-seq analysis revealed that PANoptosis activity was primarily enriched in macrophages and neutrophils. Integration of transcriptomic and computational data identified cathepsin B (CTSB) as a central regulator of PANoptosis. In vivo validation in an IAV-infected mouse model confirmed elevated expression of PANoptosis markers and upregulation of CTSB. Mechanistically, CTSB may facilitate NLRP3 inflammasome activation and promote lysosomal dysfunction-associated inflammatory cell death. These findings identify CTSB as a critical mediatoCTSBr linking lysosomal integrity to innate immune-driven lung injury and suggest that targeting CTSB could represent a promising therapeutic strategy to alleviate influenza-associated immunopathology.
Rhein, the active ingredient of rhubarb, a medicinal and edible plant, is widely used in clinical practice. In this work, we investigated the alterations of 14 bile acids and hepatic transporters after rats were administered rhein for 5 consecutive weeks. There was no obvious injury to the liver and kidney, and there were no significant changes in biochemical indicators. However, 1,000 mg/kg rhein increased the liver total bile acid (TBA) levels, especially taurine-conjugated bile acids (t-CBAs), inhibited the expression of Farnesoid X receptor (FXR) and (bile salt export pump) BSEP mRNA, and upregulated the expression of (cholesterol 7α-hydroxylase) CYP7A1 mRNA. Rhein close to the clinical dose reduced the amounts of TBAs, especially unconjugated bile acids (UCBAs), and elevated the expression of FXR and multidrug resistance-associated protein 3 (Mrp3) mRNA. These results denote that rhein is not toxic and is safe to use at a reasonable dose and timing.