Controllable Adaptive Molybdate-Oligosaccharide Nanoparticles Regulate M2 Macrophage Mitochondrial Function And Promote Angiogenesis via PI3K/HIF-1α/VEGF Pathway to Accelerate Diabetic Wound Healing.

The complex wound environment of diabetic wounds leads to poor treatment efficacy, and the inflammatory disorders and vascular injury are the primary causes of death in such patients. Herein, benefiting from the unique properties of metal ions and oligosaccharide, a sprayable, controllable, adaptive, pH-responsive nanosystem of molybdate and oligosaccharide (CMO NPs) was specially developed as an immunomodulatory and angiogenesis-promotion material for diabetic wound healing. CMO NPs exhibited pH-responsive release of Mo 2+ and oligosaccharide (COS), specifically in response to the alkalescent environment observed in diabetic wounds. CMO NPs provided an anti-inflammatory environment by promoting M2 polarization through significantly stimulating macrophage mitochondrial function. Specifically, CMO NPs with a certain concentration reduced reactive oxygen species (ROS) and tumor necrosis factor α (TNF-α) expression, and upregulated mitochondrial membrane potential (MMP), superoxide dismutase (SOD), and interleukin 10 (IL-10) expression in macrophages. Moreover, CMO NPs facilitated angiogenesis via upregulating the PI3K/HIF-1α/VEGF pathway-a critical process for the formation of new blood vessels that supply nutrients and oxygen to the healing tissue. Remarkably, CMO NPs promoted cell viability and migration of endothelial cells, and enhanced the expression of angiogenic genes (PI3K, AKT, HIF-1α, S6K, VEGF, PDGF-β, TGF-β). In vitro and in vivo studies suggest this simple but powerful nanosystem targeting mitochondrial function has the potential to become an effective treatment for diabetic wound healing. This article is protected by copyright. All rights reserved.