Wound healing activity of hydromethanolic Dioscorea bulbifera extract on male wistar rat excision wound models

Abstract

IntroductionWound healing is a complex physiological process that involves a series of coordinated events that recover structural and functional tissue integrity. The desire to promote nature-based solutions has led to the screening of various plants and herbs for their wound healing potentials with results showing the enhancement of various aspects of the wound healing process. Dioscorea bulbifera possesses a wide range of applications in folk remedies. In traditional Chinese medicine, it is used in the treatment of mumps, goitre, sore throat, gastric cancer and carcinoma of the rectum alone or in combination with other plants. The present study evaluated the effect of hydromethanolic extract of Dioscorea bulbifera (HEDB) on wound size, percentage of wound contraction and tissue hydroxyproline in male Wistar rat excision wound models. MethodsTwenty-five (25) male Wistar rats (180–200 g) were used for the study. They were divided into five (5) groups comprising five (5) animals per group. A circular excision wound (1.5–2 cm) was experimentally induced in each animal following ketamine anaesthesia. Groups I and II served as negative and positive controls and were treated with topical administration of distilled water and petroleum jelly respectively. Groups III, IV and V served as the experimental groups and were treated with 200, 400 and 800 mg/kg of HEDB topically. The diameter of the wound was measured and the wound area and percentage of wound contraction were calculated. Tissue hydroxyproline was determined using tissue excised from the healed portion of the dorsal surface of the animals via coulometric standard procedures. ResultsData from the study indicates that animals in the experimental groups (III, IV and V) had an earlier wound closure compared to the control. Animals treated with 200 mg/kg HEDB (Group III) showed complete wound closure by day 17, whereas animals treated with 400 mg/kg (Group IV) and 800 mg/kg HEDB (Group V) groups achieved complete wound closure by the 18th and 20th day of the experiment respectively. Similarly, all the animals in the experimental groups had significantly increased percentage of wound contraction compared to negative control (P < 0.05). Tissue hydroxyproline was significantly raised amongst the animals treated with 200 and 800 mg/kgHEDB compared to the negative control (p < 0.05). DiscussionEvidence from the study has shown that HEDB possesses potent wound healing activity as the present study has demonstrated that it reduced wound area, and increased wound contraction and tissue hydroxyproline on experimentally induced excision wound male Wistar rat models. These findings provide scientific evidence that validates the traditional medicinal application of Dioscorea bulbifera in promoting wound healing.