Network pharmacology and experimental validation of andrographolide’s renoprotective effects on diabetic nephropathy via AGEs-RAGE signaling and mitophagy pathways

Abstract Diabetic nephropathy (DN) is a severe diabetic complication, manifested by glomerulosclerosis, renal interstitial fibrosis and inflammation. Andrographolide (AD) is a natural compound with multiple pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, etc. However, the mechanism of AD on DN remains elusive. In this study, we integrated network pharmacology and in vitro experiments to investigate the potential targets and pathways of AD on DN, and to confirm its renoprotective effects on renal tubular epithelial cells. We screened 198 potential targets of AD and 3791 related targets of DN from public databases, and obtained 107 common targets of AD-DN. We built the protein-protein interaction network of the common targets, and performed GO and KEGG enrichment analysis, and identified 7 core targets (STAT3, IL6, PIK3CA, JUN, CASP3, MAPK1, ERBB2) and several key pathways (AGEs-RAGE signaling pathway, mitophagy, etc.) of AD-DN. We then used a high-glucose induced mouse glomerular podocyte (MPC-5) model to validate the effects of AD on DN. We found that AD could significantly reduce the cell proliferation, inflammatory factors, ROS levels, inhibit the matrix remodeling, apoptosis and autophagy of cells, and regulate the expression of core target proteins and genes of cells. Moreover, we found that STAT3 played a vital role in the process of AD treating DN, and its blockade by WP1066 could significantly weaken the renoprotective effect of AD. Our study revealed the potential mechanism of AD on DN, and provided new evidence for its clinical application.