Unraveling the Mechanism of Tangmaikang Granules in Treating Diabetic Kidney Disease Based On UPLC-MS/MS, Network Pharmacology, Molecular Docking, Molecular Dynamics Simulations, and Experimental Validation.

Background: Diabetic Kidney Disease (DKD) is a major cause of End-Stage Renal Disease (ESRD) and lacks effective treatments. Tangmaikang Granules (TMK), a multi-herb traditional Chinese medicine formulation, have shown potential in managing DKD. However, the precise active components, molecular mechanisms, and therapeutic advantages of TMK remain unclear.

Objective: This study tests the hypothesis that TMK granules exert protective effects on DKD by targeting multiple pathways involved in oxidative stress, inflammation, and apoptosis in podocytes through a multi-targeted approach. The aim was to identify TMK's bioactive components, evaluate its therapeutic potential, and uncover its molecular mechanisms in DKD.

Methods: The bioactive constituents in TMK were determined through ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Drug targets were identified using SwissTargetPrediction and SuperPred, whereas DKD-associated targets were obtained from the GeneCards, DisGeNET, OMIM, and TTD databases. A Protein-Protein Interaction (PPI) network was constructed, and key targets were identified via topological analysis. Molecular docking and dynamics simulations were performed to evaluate stable binding interactions. GO and KEGG pathway enrichment analyses were conducted to uncover relevant signaling pathways. TMK's effects on oxidative stress, inflammation, and apoptosis in podocytes were assessed using CCK-8, flow cytometry, RT-qPCR, ELISA, and Western blot assays.

Results: Thirty active compounds and 384 potential therapeutic targets were identified, with eight key targets. Pathway enrichment analysis revealed TMK's involvement in AGE-RAGE, EGFR, HIF-1, and apoptosis pathways, affecting inflammatory cytokine responses and oxidative stress. In vitro experiments demonstrated that TMK significantly reduced oxidative stress, inflammation, and apoptosis in podocytes by inhibiting the MAPK and NF-κB pathways.

Conclusion: TMK granules target DKD through a multi-component, multi-target strategy, effectively mitigating oxidative stress and suppressing inflammatory and apoptotic pathways. This study integrates advanced computational and experimental methods, demonstrating TMK's unique therapeutic potential and providing a robust foundation for its clinical application in DKD management.