Multifunctional nanofibrous membranes enhance diabetic wound healing by inhibiting endothelial pyroptosis and regulating macrophage polarization

Persistent oxidative stress and aberrant inflammatory responses are major contributors to delayed wound healing in diabetic patients. Endothelial cell pyroptosis, a form of inflammatory programmed cell death, plays a critical role in vascular dysfunction and impaired tissue regeneration in diabetic wounds. Targeting endothelial pyroptosis therefore represents a promising therapeutic strategy. This study aims to develop a multifunctional nanofibrous scaffold capable of suppressing oxidative stress-induced endothelial pyroptosis while modulating the inflammatory microenvironment to promote angiogenesis and diabetic wound repair.

In this study, a pH-responsive nanoplatform based on zinc–imidazolate metal–organic frameworks (ZIF-8) was constructed for the controlled delivery of luteolin (Lut), a natural flavonoid with anti-inflammatory and antioxidant properties. The physicochemical characteristics, drug-loading efficiency, and pH-responsive release behavior of Lut@ZIF-8 nanoparticles were systematically evaluated. The effects of Lut@ZIF-8 on oxidative stress, endothelial pyroptosis, and angiogenic function were investigated in vitro, while therapeutic efficacy was further assessed in a diabetic mouse wound model using Lut@ZIF-8-loaded fibrous scaffolds.

Lut@ZIF-8 nanoparticles exhibited uniform morphology, high drug-loading efficiency, and sustained drug release under mildly acidic conditions mimicking the diabetic wound microenvironment. In vitro, Lut@ZIF-8 effectively suppressed reactive oxygen species accumulation and inhibited endothelial cell pyroptosis by downregulating the activation of NLRP3 inflammasome components, including caspase-1 and GSDMD, thereby preserving endothelial barrier integrity and angiogenic capacity. In vivo, Lut@ZIF-8-loaded scaffolds significantly reduced inflammatory cytokine expression, enhanced collagen deposition, promoted neovascularization and re-epithelialization, and ultimately accelerated wound closure in diabetic mice.

The pH-responsive Lut@ZIF-8 nanoplatform effectively modulates oxidative stress and endothelial cell pyroptosis in diabetic wounds, thereby promoting angiogenesis and tissue regeneration. This strategy provides a promising and innovative therapeutic approach for the treatment of chronic diabetic wounds.