A Tetrahedral DNA Framework-Based Mitochondrial Anchoring System Promotes Diabetic Wound Healing via Mitophagy and Mitostress Regulation

The dysfunction of mitochondria is a prominent factor of the inflammatory microenvironment that delays diabetic wound healing. However, existing methods have limitations of inadequate regulation of mitochondrial function. Herein, a tetrahedral DNA framework-based mitochondrial anchoring system was constructed to regulate mitophagy and mitostress in diabetic wounds. This system, which is fabricated based on tetrahedral framework nucleic acids (tFNAs), is covalently linked with Rhodamine 19 to further load resveratrol, realizing the mitochondria-targeted delivery of resveratrol and sustained drug release. It can activate superoxide dismutase (SOD) to effectively scavenge mitochondrial ROS and promote mitophagy to eliminate damaged mitochondria, thus rescuing cell viability under oxidative stress, promoting cell migration, and upregulating angiogenesis and extracellular matrix-related proteins. In a diabetic skin defect model, TRh-RSV markedly accelerates wound healing by enhancing the regeneration of connective tissues and skin appendages and upregulating mitophagy. These effects are mediated through the suppression of mitochondrial oxidative stress and the concomitant modulation of mitophagy. This study highlights the potential of this system not only for the treatment of refractory diabetic wounds but also for other diseases associated with mitochondrial dysfunction.