Integrated network analysis, proteomics, and experimental validation reveal the mechanisms underlying the renoprotective effects of salvianolic acid A against diabetic nephropathy.

ETHNOPHARMACOLOGICAL RELEVANCE Salvianolic acid A (SAA), a major bioactive constituent of Salvia miltiorrhiza, has attracted considerable attention because of its diverse pharmacological activities in metabolic and vascular disorders. Diabetic nephropathy (DN) is one of the most serious microvascular complications of diabetes and remains a leading cause of end-stage renal disease worldwide. Although increasing evidence has demonstrated the renoprotective effects of SAA, the precise molecular mechanisms underlying its therapeutic actions in DN remain incompletely understood.

Aim

OF THE STUDY This study aimed to systematically investigate the therapeutic mechanisms of SAA against DN by integrating network pharmacology, quantitative proteomics, molecular docking, and experimental validation.

Materials And Methods

Potential therapeutic targets and signaling pathways of SAA in DN were identified through network pharmacology and quantitative proteomic analyses. A high-fat diet/streptozotocin-induced DN rat model was established to evaluate the renoprotective effects of SAA in vivo. Renal function, histopathological alterations, inflammatory responses, oxidative stress, mitochondrial homeostasis, autophagy-related proteins, and macrophage polarization were assessed. Molecular docking was performed to validate the interactions between SAA and key target proteins.

Results

SAA significantly improved renal function and attenuated histopathological injury in DN rats. In addition, SAA reduced oxidative stress, suppressed inflammatory responses, restored mitochondrial homeostasis, and inhibited M1 macrophage polarization. Integrated network pharmacology and proteomic analyses identified the PI3K/Akt/mTOR signaling pathway as a critical target of SAA, which was further supported by molecular docking and experimental validation. Mechanistically, SAA inhibited PI3K/Akt/mTOR activation and restored autophagy-related signaling, thereby alleviating renal injury in DN.

Conclusion

SAA exerts renoprotective effects against DN through modulation of PI3K/Akt/mTOR-mediated autophagy and macrophage polarization, leading to attenuation of oxidative stress, inflammatory responses, mitochondrial dysfunction, and macrophage polarization. These findings provide mechanistic insights into the therapeutic potential of SAA and support its further development as a candidate treatment for DN.