Carboxymethyl cellulose/sericin-based hydrogels with intrinsic antibacterial, antioxidant, and anti-inflammatory properties promote re-epithelization of diabetic wounds in rats

Diabetic wound healing encounters significant challenges due to the extreme oxidative stress resulting from excessive inflammation and microbial infections, disrupting the typical cascade of wound healing and thwarting the re-epithelialization of skin tissues. Benefiting from the biological activities of carboxymethyl cellulose (CMC) and sericin, we thus fabricated multifunctional hydrogels of CMC-Sericin. The hydrogel revealed high swelling performance alongside its porous structure. The incorporation of sericin bestowed the CMC-Sericin hydrogels with a prominent capacity to scavenge free radicals and antibacterial activity. In vivo investigations using diabetic full-thickness excision wounds demonstrated the capability of CMC-Sericin dressing to enhance diabetic wounds in rats treated or untreated with insulin concurrently. Furthermore, histopathological examinations manifested the skin tissue regeneration evidenced by the development of skin appendages like hair follicles and collagen deposition after treatment with CMC-Sericin hydrogel. Moreover, the levels of antioxidant parameters, including GSH and SOD, were substantially augmented and associated with a significant diminution in lipid peroxidation, implying a decrease in oxidative stress in the tissues. Beyond that, CMC-Sericin dressing downregulated the pro-inflammatory markers and upregulated the heat shock proteins, indicating the restoration of physiological features in cells. Strikingly, CMC-Sericin dressing remarkably promoted the healing of diabetic wounds without insulin treatment.