Molecular mechanism of Fagopyri Dibotryis Rhizoma in treatment of acute lung injury based on network pharmacology and in vitro experiments

The present study explored the mechanism of Fagopyri Dibotryis Rhizoma(FDR) and its main active components in the treatment of acute lung injury(ALI) based on the network pharmacology and the in vitro experiments. The main active components of FDR were obtained from the TCMSP database and screened by oral bioavailability and drug-likeness. The related target proteins of FDR were retrieved from the PubChem database, and the target genes related to ALI were screened out from the GeneCards database. A protein-protein interaction(PPI) network of compound target proteins and ALI target genes was constructed using STRING 11.0. Ingenuity Pathway Analysis(IPA) platform was used to analyze the common pathways of the potential compound target proteins of FDR and ALI target genes, thereby predicting the key targets and potential signaling pathways of FDR for the treatment of ALI. Finally, the potential pathways and key targets were verified by the in vitro experiments of lipopolysaccharide-induced RAW264.7 cells intervened by epicatechin(EC), the active component of FDR. The results of network pharmacology showed that 15 potential active components such as EC, procyanidin B1, and luteolin presumedly functioned in the treatment of ALI through nuclear transcription factor-κB(NF-κB) signaling pathway, transforming growth factor-β(TGF-β) signaling pathway, and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK) signaling pathway through key targets, such as RELA(P65). The results of in vitro experiments showed that 25 μmol·L~(-1) EC had no toxicity to cells and could inhibit the expression of the p65-phosphorylated protein in the NF-κB signaling pathway to down-regulate the expression of downstream inflammatory cytokines, including tumor necrosis factor-α(TNF-α), IL-1β and nitric oxide(NO), and up-regulate the expression of IL-10. These results suggested that the therapeutic efficacy of FDR on ALI was achieved by inhibiting the phosphorylation of p65 protein in the NF-κB signaling pathway and down-regulating the level of proinflammatory cytokines downstream of the signaling pathways.