Network pharmacology based research into the effect and mechanism of Xijiao Dihuang decoction against sepsis

Sepsis is a critical illness that contributes a high mortality, while Xijiao Dihuang decoction (XJDHT) has been used in treatment against sepsis for many years by clinical doctors. Clinical studies confirmed a good efficacy of XJDHT against sepsis. The aim of this study is to observe the efficacy of XJDHT in sepsis model rats and macrophages activated by LPS, and to verify the underlying mechanisms. The key components of XJDHT and its targets against sepsis were analyzed and selected by network pharmacology. The potential mechanisms that XJDHT regulates the progress of sepsis were verified in sepsis rats and NR8383 cell lines. XJDHT at a dose of 25 mg/kg was administrated to rats which endured cecal ligation and perforation (CLP). After MTT assay, XJDHT at a dose of 4 mg/mL was selected to treat NR8383 cell lines activated by LPS. In vivo experiment, the survival of the rats was assessed. The content of cytokine in serum were assessed by Enzyme-linked immunosorbent assays (ELISA). Contents of cytokine and key molecules in relative signaling pathway were assessed by immunohistochemical method. The pathway protein expressions were detected by Western blotting. In vitro experiment, immunofluorescence was used to assess the content of cytokine and signaling pathway. A total of 42 targets of XJDHT against sepsis were identified by network pharmacology. After eliminating overlapping compounds and proteins, there were 8 compounds in XJDHT that associating with the 42 sepsis-related targets. NF-κB and HIF-1α signaling pathway were recognized to play important role for XJDHT against sepsis. XJDHT improved survival rate in the XJDHT group compared with the model group. The contents of IL-6 increased in the model group compared with the control group with ELISA and immunohistochemistry, while XJDHT reduced the content of IL-6. The expressions of p65 and HIF-1α reduced significantly in the XJDHT group compared with the model group. In vitro study, the content of IL-6 elevated significantly after LPS stimulation, while XJDHT reduced this increase. Furthermore, expressions of protein of p65 and HIF-1α decreased significantly compared with the LPS group. To conclude, our study demonstrated that XJDHT at a dose of 25 g/kg is capable of improving the survival of sepsis via regulating the NF-κB and HIF-1α signaling pathway.