Hypoglycemic and hypolipidemic effects of the aqueous fresh leaves extract of Clerodendrum capitatum in Wistar rats

Diabetes mellitus, the most common endocrine disorder of carbohydrate metabolism, is treated in the African traditional phytotherapies with the cold water decoction of Clerodendrum capitatum (CC). In the current study, the hypoglycemic and hypolipidemic effects of fresh leaves aqueous extract of CC were studied in four groups of six adult Wistar rats per group and weighting 120 - 150 g, by administering graded oral doses (100, 400 and 800 mg/kg/day) of the extract for 14 days. On the 15th day, the fasted rats were anesthetized under inhaled halothane and blood samples obtained through cardiac puncture. Phytochemical analysis of CC extract was conducted using standard procedures while the preliminary acute oral toxicity study was also conducted using limit dose test of Up and Down Procedure at a limit dose of 5000 mg/kg body weight/oral route. Results of the study showed CC to cause significant (p < 0.05, p < 0.001) dose dependent hypoglycemic and hypolipidemic effects but had no effect on the pattern of weight gain in the treated rats. Although no lethal effect was recorded with CC oral administration for up to 5000 mg/kg body weigh/oral route, but there was an associated transient somatomotor and behavioral toxicities. Phytochemical results revealed the presence of saponins, flavonoids, alkaloids, tannin, glycosides and reducing sugars in the extract. Thus, the folkloric use of Clerodendrum capitatum in the treatment of suspected type 2 diabetics has a positive correlation with scientific data generated in this study. (C) 2007 Elsevier Ireland Ltd. All rights reserved.