Preneoplastic lesion preventive and hepatoprotective effects of <i>Terminalia brownii</i> fresen stem extracts in experimental rat Model

Abstract

Terminalia brownii Fresen (Combretaceae) is a multipurpose medicinal plant used for various therapeutic applications including cancer. There is a need to validate extracts of this plant in order to provide scientific evidence for its claimed traditional use. Powdered stem of T. brownii was extracted using water and 70% ethanol. Acute toxicity of the two extracts was assessed in male Wistar rats. Nine groups of Wistar rats each with a sample size of five rats were given intraperitoneal (ip) injections of 1,2-dimethylhydrazine (DMH) (20 mg/kg) weekly for five consecutive weeks to induce colon preneoplastic lesion while a normal control group received ip injection of normal saline. At the end of the fifth week, each group of rats was treated by oral gavage aqueous or 70% ethanol extract of T. brownii stem, at 250 mg/kg, 500 mg/kg and 750 mg/kg dose daily for four weeks, or oral capecitabine at 30 mg/kg/day for fourteen days. The rats that took normal saline ip injection and one group of rats that took DMH injection were given the same amount of normal saline orally for four weeks. At the end of the experimental period (nine weeks), biochemical and histological analysis were performed. The findings of the study indicate that the incidence of multiple plaque lesions (MPLs) in DMH only treated group was 100%, while it was 0% in normal saline group. Groups which were treated with T. brownii extract showed a significant reduction in MPL incidence. Especially, the 750 mg/kg hydroethanolic T. Brownii extract treated group showed no incidence of MPL similar to the capecitabine treated and normal control groups. Significant elevation of liver function parameters were recorded in capecitabine treated groups, while lower levels were noted in groups treated with T. brownii extracts. This study showed that T. brownii extracts have preneoplastic lesion preventive effect and hepatoprotective potential in experimental rat model. The aqueous extract showed a better hepatoprotective activity than the hydroethanolic extract, whereas the later demonstrated superior chemopreventive potential to the former. Further studies on chemical elucidation are required to identify and develop lead compounds.

Keywords: Terminalia brownii, dimethylhydrazine, multiple plaque lesions, preneoplastic, hepatoprotective