Cryogenic 3D printed hydrogel scaffolds loading exosomes accelerate diabetic wound healing

Diabetic wounds represent a pressing concern affecting the health and quality of life of patients. Despite the continuous improvement in therapeutic strategy, diabetic wounds remain a worldwide challenge. Vascular dysfunction, in part due to hyperglycemia, is a well-identified factor contributing to inadequate healing in diabetic wounds. In the current study, we utilize an extrusion-based cryogenic 3D printing technology to construct decellularized small intestinal submucosa (SIS) combined with mesoporous bioactive glass (MBG) and exosomes to fabricate a produce a 3D scaffold dressing (SIS/MBG@Exos) which permits sustained release of bioactive exosomes. The SIS/MBG@Exos hydrogel scaffolds possess a good 3D structure with an suitable porosity, biocompatibility and hemostasis ability, which could promote the proliferation, migration and angiogenesis of Human umbilical vein endothelial cells (HUVECs). The results of diabetic wounds in vivo indicate that the SIS/MBG@Exos hydrogel scaffolds accelerate diabetic wound healing through increasing the blood flow of wounds and stimulating the angiogenesis process of the diabetic wound. The SIS/MBG@Exos hydrogel scaffolds also promote granulation tissue formation, well-organized collagen fiber deposition, functional new blood vessel growth, factors promoting wound healing. Taken together, this research presents a promising novel strategy for the treatment of diabetic wounds.