Anti-inflammatory screening of ethanolic leaf extract of Vernonia arborea Buch. –Ham.in formalin induced albino wistar rats

Context: The therapeutic potential of the genus Vernonia has been well documented over the years. However the pharmacological potential of the plant Vernonia arborea (Asteraceae) has been relatively less explored. Objective: To investigate the anti inflammatory effect of the ethanol leaf extract of V. arborea against formalin induced inflammation in rats. Materials and methods: Formalin induced inflammation method was used to induce inflammation in rats.0.1 ml/kg body weight (b.w.) of formalin was administered to the rats via sub-plantar injection to induce inflammation. The rats were pretreated with ethanol leaf extract of V. arborea at concentrations of 100, 200 and 300 mg/kg b.w. once daily for 30 days. Indomethacin (25 mg/kg b.w.) was used as standard drug. Biochemical and hematological parameters along with levels of antioxidant enzymes were evaluated. Results: Administration of formalin reduced antioxidant enzyme levels, total RBC and Hb. Pretreatment with ethanol leaf extract of V.arborea at dose dependent levels significantly increased (p<0.05)the levels of the above parameters. A significant increase (p<0.05) in paw thickness, level of serum enzymes (Aspartate transaminase, Alanine transaminase, Alkaline phosphatase and Creatine kinase), Lipid peroxide and leucocytes was observed in the rats induced with formalin, while these levels were normalized on pretreatment with ethanol leaf extract of V.arborea. Conclusion: The results of the present investigation demonstrate the antioxidant and anti-inflammatory potential of the ethanol leaf extract of V.arborea. However, it is imperative to isolate and purify the active principles involved in the pharmacological potency of this plant and determine its mechanism of action.