Topical Application of Robusta Coffee Extract Gel Enhances Angiogenesis, Fibroblast, Collagen Density, and Epithelial Thickness on Wound Healing of Skin Graft in Rats

Abstract

Skin graft is a reconstructive procedure commonly used to cover defects or wounds. The majority of post-skin graft treatments use topical agents or the application of modern dressings. However, these treatments have been considered to have disadvantages, such as being limited and expensive. Abundant natural ingredients can be used as alternatives to aid the healing process, one of which is robusta coffee. Robusta coffee is reported to contain active ingredients such as CGA, flavonoids, and saponins. This study aimed to prove the wound healing effect of robusta coffee extract in gel dosage form on the skin graft model in rats. Thirty male Long Evans rats were divided into three groups: negative control (gel base), positive control (1% kojic acid gel), and 5% robusta coffee extract gel (RCEG). A 2 x 2cm split-thickness skin graft was harvested from the dorsal skin of the rat and then fixed to the split-thickness wound at the donor site. Skin graft tissues were taken by biopsy on days 7, 14, and 21 for histopathological evaluation by assessing angiogenesis, fibroblasts, collagen density, and epithelial thickness. Our results found that the number of blood vessels, fibroblast cell count, collagen density percentage, and epithelial thickness were significantly higher in the 5% RCEG group on days 7, 14, and 21 compared to the control group. In conclusion, topical application of 5% RCEG can enhance wound healing of skin graft by improving angiogenesis, fibroblasts, collagen density, and epithelial thickness.