CD44-Targeted Chitosan Nanoparticles Delivering Ginsenoside Rg1 Restore Mitochondrial Homeostasis in Diabetic Kidney Disease via AMPK/mTOR-Mediated Regulation of Autophagy and Pyroptosis

Objective Mitochondrial dysfunction and dysregulated cell death are key drivers of diabetic kidney disease (DKD) progression. This study aimed to construct CD44-targeted chitosan (Cs) nanoparticles encapsulating ginsenoside Rg1 (CD44-Cs@Rg1) for targeted delivery, and to evaluate their ability to regulate autophagy, pyroptosis, and mitochondrial function in DKD. Methods CD44-Cs@Rg1 nanoparticles were synthesized using a covalent modification strategy. Their targeting uptake, effects on GSDMD-mediated pyroptosis, autophagic flux, and energy metabolism were systematically evaluated in renal tubular epithelial cells under high-glucose (HG) conditions and in DKD mouse models. Mitochondrial function was assessed by Western blotting, immunostaining, MitoSOX, JC-1, and ATP assays. Transcriptomic profiling and pharmacological interventions were applied to elucidate the involvement of the AMPK/mTOR signaling axis. Results CD44-Cs@Rg1 nanoparticles were efficiently internalized by renal tubular epithelial cells, significantly reducing pyroptosis while restoring autophagic flux through AMPK activation and mTOR inhibition. These effects improved mitochondrial membrane potential, reduced reactive oxygen species accumulation, and enhanced ATP production. In vivo , CD44-Cs@Rg1 treatment markedly ameliorated renal dysfunction and histopathological injury in DKD mice. Transcriptomic and protein-level analyses consistently revealed enrichment of pathways related to AMPK signaling, autophagy, and energy metabolism. Conclusion CD44-targeted Cs nanoparticles enable precise delivery of ginsenoside Rg1 to renal tubular cells in DKD, restoring mitochondrial homeostasis and regulating autophagy–pyroptosis balance via the AMPK/mTOR axis. This nanotherapeutic platform demonstrates strong translational potential for DKD treatment.