Atelocollagen-based hydrogel loaded with Cotinus coggygria extract for treatment of type 2 diabetic wounds

Abstract Diabetes, a chronic metabolic disease, causes complications such as chronic wounds, which are difficult to cure. New treatments have been investigated to accelerate wound healing. In this study, a novel wound dressing from fibroblast-laden atelocollagen-based hydrogel with Cotinus coggygria extract was developed for diabetic wound healing. The antimicrobial activity of C. coggygria hexane (H), dichloromethane (DCM), dichloromethane:methanol (DCM-M), methanol (M), distilled water (DW) and traditional (T) extracts against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis and Candida albicans , as well as their cytotoxic effects on fibroblasts were determined. While fibroblast growth was significantly ( p < 0.05) promoted with DCM (121.41 ± 1.04%), M (109.40 ± 5.89%) and DW (121.83 ± 6.37%) extracts at their lowest concentrations, 2000 μg ml −1 DCM and 7.8 μg ml −1 T extracts had both non-cytotoxic and antifungal effects. An atelocollagen-based hydrogel was produced by thermal crosslinking, and its pore size (38.75 ± 7.67 μm), water content (96.63 ± 0.24%) and swelling ratio (27.21 ± 4.08%) were found to be suitable for wound dressings. A significant increase in the deoxyribonucleic acid amount (28.27 ± 1.41%) was observed in the plain hydrogel loaded with fibroblasts after 9 d of incubation, and the hydrogel had an extensively interconnected cellular network. The hydrogels containing DW and T extracts were applied to wounds generated in an in vitro 3D type-2-diabetic human skin model. Although the incubation period was not sufficient for closure of the wounds in either of the treatments, the hydrogel with T extract stimulated more fibroblast migration. In the fibroblast-laden version of the hydrogel with T extract, no wound closure was observed but more keratinocytes migrated to the wound region. These positive outcomes underline the potential of the developed wound dressing as a powerful alternative to improve diabetic wound healing in clinical practice.