A Systematic Study of the Mechanism of Acacetin Against Sepsis Based on Network Pharmacology and Experimental Validation.

Sepsis is a dysregulated systemic response to infection, and no effective treatment options are available. Acacetin is a natural flavonoid found in various plants, including Sparganii rhizoma, Sargentodoxa cuneata and Patrinia scabiosifolia. Studies have revealed that acacetin potentially exerts anti-inflammatory and antioxidative effects on sepsis. In this study, we investigated the potential protective effect of acacetin on sepsis and revealed the underlying mechanisms using a network pharmacology approach coupled with experimental validation and molecular docking. First, we found that acacetin significantly suppressed pathological damage and pro-inflammatory cytokine expression in mice with LPS-induced fulminant hepatic failure and acute lung injury, and in vitro experiments further confirmed that acacetin attenuated LPS-induced M1 polarization. Then, network pharmacology screening revealed EGFR, PTGS2, SRC and ESR1 as the top four overlapping targets in a PPI network, and GO and KEGG analyses revealed the top 20 enriched biological processes and signalling pathways associated with the therapeutic effects of acacetin on sepsis. Further network pharmacological analysis indicated that gap junctions may be highly involved in the protective effects of acacetin on sepsis. Finally, molecular docking verified that acacetin bound to the active sites of the four targets predicted by network pharmacology, and in vitro experiments further confirmed that acacetin significantly inhibited the upregulation of p-src induced by LPS and attenuated LPS-induced M1 polarization through gap junctions. Taken together, our results indicate that acacetin may protect against sepsis via a mechanism involving multiple targets and pathways and that gap junctions may be highly involved in this process.

Pirfenidone attenuates homocysteine­induced apoptosis by regulating the connexin 43 pathway in H9C2 cells.

Pirfenidone (PFD) is an anti­fibrotic agent that is clinically used in the treatment of idiopathic pulmonary fibrosis. PFD has been shown to exert protective effects against damage to orbital fibroblasts, endothelial cells, liver cells and renal proximal tubular cells; however, its effect on myocardial cell apoptosis remains unclear. The present study aimed to characterize the effects of PFD on homocysteine (Hcy)­induced cardiomyocyte apoptosis and investigated the underlying mechanisms. H9C2 rat cardiomyocytes were pre­treated with PFD for 30 min followed by Hcy exposure for 24 h. The effects of PFD on cell cytotoxicity were evaluated by CCK­8 assay. The apoptosis rate of each group was determined by flow cytometry. The protein and mRNA levels of connexin 43 (Cx43), Bax, B­cell lymphoma­2 (Bcl­2) and caspase­3 were measured by western blot analysis and reverse transcription­quantitative PCR, respectively. The present results demonstrated that the apoptotic rate increased following Hcy exposure, whereas the apoptotic rate significantly decreased following PFD pre­treatment. Furthermore, the ratio of Bax/Bcl2 was upregulated following Hcy exposure, and Hcy upregulated the expression levels of cleaved caspase­3 and Cx43. Notably, these effects were prevented by PFD. Additionally, the effects of PFD were inhibited by the Cx43 agonist, AAP10. In summary, the findings of the present study demonstrate that PFD protects H9C2 rat cardiomyocytes against Hcy­induced apoptosis by modulating the Cx43 signaling pathway.