Evaluation of wound healing activity of Allamanda cathartica. L. and Laurus nobilis. L. extracts on rats

ABSTRACT

BACKGROUND: Allamanda cathartica. L. is a perennial shrub used in traditional medicine for treating malaria and jaundice. Laurus nobilis. L. is a tree and has been used for its astringent, healing and diuretic properties. The objective of this study was to investigate the aqueous extracts of Allamanda and Laurus nobilis to evaluate their wound healing activity in rats.METHODS: Excision and incision wound models were used to evaluate the wound healing activity of both the extracts on Sprague Dawley rats. In each model, animals were divided into four groups of 10 animals each. In both the model, group 1 served as control and group 2 as reference standard. In an excision wound model, group 3 animals were treated with Allamanda (150 mg kg-1 day-1) and group 4 animals were treated with Laurus nobilis (200mg kg-1 b.w day-1) for 14 days respectively. In the case of incision wound model, group 3 and 4 animals were treated with the extracts of Allamanda and Laurus respectively for 10 days. The effects of vehicles on the rate of wound healing were assessed by the rate of wound closure, period of epithelialisation, tensile strength, weights of the granulation tissue, hydroxyproline content and histopathology of the granulation tissue.RESULTS: The aqueous extract of Allamanda promoted wound healing activity significantly in both the wound models studied. High rate of wound contraction (P < .001), decrease in the period of epithelialisation (10.2 ñ0.13), high skin breaking strength (440.0 ñ 4.53), significant increase in the weight of the granulation tissue (P <.001) and hydroxyproline (P < .001) content were observed in animals treated with the aqueous extract of Allamanda. Histological studies of the granulation tissue from the Allamanda treated group showed the presenceof a lesser number of inflammatory cells, and increased collagen formation than the control.