Abstract: Objective To screen potential traditional Chinese medicine and their active monomer ingredients for treatment of diabetic nephropathy (DN) through the mechanism of caspase-1-mediated pyroptosis. Methods Using the Chinese Medicine System Pharmacology Analysis Platform (TCMSP), we screened traditional Chinese drugs and their active monomer components targeting caspase-1, and searched for the potential gene targets of the monomer components using GeneCards database. Cytoscape was used to construct the monomer compound-gene target network. Gene ontology (GO) functional enrichment analysis and Kyoto Gene and Gene Encyclopedia (KEGG) pathway enrichment analysis were used to predict the molecular mechanism of the screened traditional Chinese medicine and monomers. In SD rat models of diabetic mellitus (DM), we tested the therapeutic effect of ginsenoside Rh2 (daily dose of 20 mg/kg for 12 weeks) by examining renal pathology with HE staining and detecting the expressions of pyroptosis marker proteins caspase-1, GSDMD, IL-1β and IL-18 in the renal tissues using Western blotting, the serum levels of IL-1β and IL-18 and activities of cathepsin B and cathepsin L. Results Ginsenoside Rh2 could effectively dock with caspase-1 molecule. Fourteen targets were identified in ginsenoside Rh2 target network. GO function enrichment analysis revealed 27 GO terms associated with molecular function (4 terms), cell component (10 terms) and biological process (13 terms). KEGG pathyway enrichment analysis identified 4 signaling pathways involving lysosomes, glycosaminoglycan degradation, galactose metabolism, and sphingolipid metabolism pathways. In the animal experiment, treatment with ginsenoside Rh2 significantly alleviated renal pathologies and down-regulated the expressions of pyroptosis marker proteins (cleaved caspase-1, GSDMD-N, IL-1β and IL-18) (P<0.05 or 0.01), lowered serum levels of IL-1β and IL-18 (P<0.01), and enhanced the activities of cathepsin B and cathepsin L in the serum of the diabetic rats. Conclusion Ginsenoside Rh2 may inhibit caspase-1-mediated pyroptosis through the lysosome pathway to improve kidney damages in rat models of DN.

Key words: diabetic nephropathy, pyroptosis, caspase-1, network pharmacology, ginsenoside Rh2, lysosome pathway