[Mechanism of Panax notoginseng saponins in treating diabetic kidney disease based on network pharmacology and experimental verification]

This study aims to investigate the therapeutic effect and mechanism of Panax notoginseng saponins(PNS) on diabetic kidney disease(DKD) based on network pharmacology, molecular docking, animal experiments. Network pharmacology was employed to screen the potential targets, and STRING was employed to build the protein-protein interaction network. Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses were carried out for the core targets screened out, and a ″components-targets-pathways″ visualization network was constructed to predict the potential mechanism of PNS in treating DKD. Five active ingredients were screened from PNS, the core targets of which for treating DKD were AKT1, STAT3, ESR1, HSP90AA1, MTOR, et al. The KEGG enrichment analysis showed that the pathways related to PNS for treating DKD included the pathway in cancer, chemical carcinogenesis-receptor activation, and PI3K-AKT signaling pathway. GO analysis revealed that protein binding, homologous protein binding, enzyme binding, and ATP binding were the main biological processes involved in the treatment of DKD with PNS. Male 6-week-old db/db mice were randomized into model, dapagliflozin, and low-dose and high-dose PNS groups, with 10 mice in each group. Ten 6-week-old db/m mice were used as the control group. Mice were administrated with corresponding drugs or distilled water(control and model groups) by gavage once a day for 8 weeks. The body weight, fasting blood glucose, kidney index, microalbuminuria, creatinine, microalbuminuria/creatinine ratio, and urea nitrogen content in the urine of mice were determined. Hematoxylin-eosin(HE) staining, periodic acid-Schiff(PAS) staining, and Masson staining were performed to observe the protective effect of PNS on the renal tissues in db/db mice. The results showed that PNS could significantly reduce the fasting blood glucose level and improve the renal damage in db/db mice. Western blot results showed that PNS down-regulated the protein levels of p-AKT1 and p-STAT3 and decreased the p-AKT1/AKT1 and p-STAT3/STAT3 ratios. In addition, high-dose PNS down-regulated the protein level of PIK3CA. In conclusion, PNS may exert the kidney-protecting effects in DKD by inhibiting STAT3 via the PI3K-AKT signaling pathway.