Active Components and Mechanism of Rhei Radix et Rhizoma on Renal Fibrosis Based on Network Pharmacology / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the active components, potential targets and signaling pathways of Rhei Radix et Rhizoma in the treatment of renal fibrosis based on the network pharmacology method, and then to verify the target genes in vitro. Method:Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and Traditional Chinese Medicine Integrated Database (TCMID) were retrieved to obtain the main active ingredients of Rhei Radix et Rhizoma. The potential anti-renal fibrosis targets of Rhei Radix et Rhizoma were predicted by similarity ensemble approach (SEA), Swiss Institute of Bioinformatics (SIB) and GeneCards Database. Target protein-protein interaction (PPI) network was constructed by using String Version 10.5 database. David 6.8 software was used for gene ontology (GO) enrichment analysis and the Kyoto Encyclopedia of genes and genomes (KEGG) pathway enrichment analysis of the key targets. Cytoscape Version 3.6.0 software was used for visualized analysis of PPI network, active ingredient-key target network and the ingredient-target-signal pathway network. In combination with Malachards database, the signal pathways with high correlation with renal fibrosis were screened. Then, cell experiments were used for verification HK-2 cells were selected to establish fibrosis model by transforming growth factor-β1 (TGF-β1) stimulation. The cells were treated with rhein for 48 hours. Western blot assay was used to detect the protein expression level of hypoxia inducible factor-1 α (HIF-1 α), vascular endothelial growth factor (VEGF), and platelet-derived growth factor receptor-α (PDGFR-α). Protein expression levels of E-cadherin and α smooth muscle actin (α-SMA) were detected by immunofluorescence. Apoptosis was detected with flow cytometry. Result:Totally 17 active ingredients of Rhei Radix et Rhizoma and 424 targets of anti-renal fibrosis effect were screened out, including five key targets protein kinase B(Akt)1, mitogen activated protein kinases 3(MAPK3), epidermal growth factor receptor(EGFR), interleukin(IL)-6 and VEGFA in turn. The biological process of GO enrichment mainly involved signal transduction, cell proliferation and apoptotic process. The results of KEGG pathway enrichment showed that phosphatidylinositol 3-kinase(PI3K)/Akt, HIF-1, VEGF, and forkhead transcription factor (FoxO) pathways were related to the anti-renal fibrosis mechanism of Rhei Radix et Rhizoma. Results of the in vitro experiment proved that rhein could inhibit the expression of E-cadherin, α-SMA, HIF-1α, VEGF and PDGFR-α. In addition, rhein inhibited apoptosis induced by TGF-β1 in HK-2 cells. Part of the prediction results of network pharmacology were verified. Conclusion:This study reflects the multi-component, multi-target and multi-pathway mechanism characteristics of Rhei Radix et Rhizoma. The mechanisms of its anti-renal fibrosis effects may be related to inhibiting HIF-1 α / VEGF /PDGFR-α signaling pathway, apoptosis and epithelial-mesenchymal transition (EMT) of renal tubular epithelial cells.