Evaluation of collagen type I and III, TGF-β1, and VEGF gene expression in rat skin wound healing treated by alginate/chitosan hydrogel containing crocetin

Skin tissue engineering is one of the popular strategies are used to improve the wound healing process. In this study, different concentration of Crocetin (Crot) were loaded into a three-dimensional (3D) alginate (Alg) and chitosan (CS) hydrogel to improve wound healing process. After hydrogel preparation, it is characterized with different experiments such as morphology evolution, water absorption, cumulative release, weight loss, hemo- and cytocompatibility, cell viability, and antibacterial properties. Then, the therapeutic role of the prepared hydrogel was investigated in a full-thickness dermal wound in a rat model with analyzing RNA expression and histology. The results showed that fabricated hydrogels had sufficient porosity and the weight loss test verified the appropriate biodegradability of the prepared hydrogel (about 90% after 14 days) that can release enough of the Crot without any toxicity effect. In addition, the in vivo findings showed that the alginate/chitosan/crocetin 150 µM group had the highest wound closure percentage, re-epithelialization, and gene expression. Furthermore, rt-PCR revealed that 150 µM crocetin increased the expression of Collagen type I, III, VEGF, and TGF-β mRNA. Overall, this research indicates that 3D Alg/CS hydrogels containing 150 µM crocetin may be used in the clinic to treat skin injuries.