Skin wound healing is complex and involves the processes of many factors, among which angiogenesis and inflammatory responses play important roles. New blood vessels provide nutrition and oxygen for skin wound repair. Cytokines in skin wounds, which include pro-inflammatory and anti-inflammatory factors, can modulate the inflammatory response. Therefore, treatment strategies that promote angiogenesis and modulate the inflammatory response in skin wounds can accelerate skin wound healing. This study explored the effects of peptide Ser-Ile-Lys-Val-Ala-Val (SIKVAV)-modified chitosan hydrogels in skin wound healing. General observation demonstrated that SIKVAV-modified chitosan hydrogels promoted the contraction of skin wounds compared with the negative and positive controls. Masson's trichrome staining indicated that peptide-modified chitosan hydrogels accelerated the deposition of more collagen fibers in the skin wounds compared with the negative and positive controls. Immunohistochemistry assays showed that more myofibroblasts were deposited and more angiogenesis was found in skin wounds treated with peptide-modified chitosan hydrogels compared with the negative and positive controls. In addition, qRT-PCR assays showed that peptide-modified chitosan hydrogels promoted the expression of TGF-β1 (transforming growth factor-β1) mRNA and inhibited the expression of TNF-α (tumor necrosis factor-α) mRNA and IL-1β (Interleukin-1β) mRNA and IL-6 (Interleukin-6) mRNA in skin wounds. Taken together, these results indicate the potential of SIKVAV-modified chitosan hydrogels in skin wound healing as complex biomaterials.
Keywords: SIKVAV; angiogenesis; chitosan hydrogel; cytokine; skin wound healing.