Elucidating the therapeutic targets and multi-target mechanisms of salvianolic acid A for diabetic nephropathy.

Diabetic nephropathy (DN) is a leading cause of chronic kidney disease. Salvianolic acid A (SAA) has shown promising therapeutic potential against DN, yet its underlying mechanisms and precise molecular targets remain incompletely elucidated. Potential targets of SAA were predicted using SwissTargetPrediction and SuperPred, with its drug-like properties evaluated by ADMET analysis. Diabetic nephropathy (DN)-related targets were collected from GEO, CTD, and GeneCards databases. Shared targets underwent GO and KEGG enrichment analyses. Core targets were identified through topological analysis in Cytoscape, machine learning, and Mendelian randomization validation. Molecular docking and dynamics simulations assessed the binding affinity and stability between SAA and core targets. Single-cell RNA sequencing data revealed their cell type-specific expression in kidney tissues. Experimental validation was performed using an in vitro high glucose-induced podocyte injury model analyzed by RT-qPCR. The intersection of 212 drug targets with 5,097 disease targets yielded 134 potential therapeutic targets for salvianolic acid A in DN. Machine learning and Mendelian randomization further identified eight targets with causal relationships to DN. Molecular docking demonstrated strong binding affinities of salvianolic acid A to the domains of FYN, AKR1B1, TNF, GALK1, HMGCR, MAP2K2, SCN4A, and ITGA5. Single-cell analysis revealed distinct expression patterns across different renal cell types. In vitro experiments demonstrated that SAA effectively protected podocytes from HG-induced injury. SAA alleviates diabetic nephropathy through multi-target mechanisms, influencing key genes involved in disease progression. This study provides a systematic elucidation of the therapeutic basis for SAA and supports its further clinical development.