WOUND-HEALING ACTIVITY OF DIOSCOREA PRAEHENSILIS IS ASSOCIATED WITH UPREGULATION OF VEGF GENE EXPRESSION IN A RAT MODEL

Abstract

A wound is a physical injury that compromises the integrity of the skin or underlying tissues. A significant cost is associated with the management of chronic wounds worldwide. Dioscorea praehensilis (DP) is used traditionally to treat inflammatory conditions, scorpion bites, dyspepsia, and ulcers. We evaluated the wound-healing properties of the crude methanol extract of Dioscorea praehensilis in rats. We investigated its effect on vascular endothelial growth factor (VEGF) gene expression to understand its mechanism. DP rhizomes were extracted by maceration in 80% methanol. Ointment formulation was done using the Simple Ointment BP formula at varying concentrations of DP (2.5%, 5%, and 10%). Excision wounds sized about 300 mm2 were made with the aid of surgical scissors. Treatment was done for fifteen days. Silver sulfadiazine and simple ointment BP were used as positive and negative controls, respectively. The rate of wound contraction was measured at a three-day interval. The mechanism of the wound-healing property was investigated by evaluating VEGF gene expression in rat aortic rings cultured in 75, 125, 250, 500, and 1000 µg/mL of DP. DP ointment exhibited an inverse dose-dependent wound-healing effect, i.e, activity decreasing as the concentration increased, with the lowest concentration (2.5%) yielding the highest activity. Furthermore, VEGF gene expression significantly increased in the aortic rings treated with 500 and 1000 µg/mL of DP compared to the negative control. In conclusion, the ability of DP to upregulate the expression of the VEGF gene may contribute to its wound-healing properties in rats.