Evaluation of sub-acute toxicity profile of Combretum dolichopetalum (E&L) methanol leaf extract in Wistar rats

Abstract

This study evaluated the safety of the ethnomedicinal plant, Combretum. dolichopetalum methanol extract (CDME) in Wistar rats using the sub-acute toxicity model. Twenty-four adult male Wistar rats were randomly divided into 4 groups of 6 rats each. Group A (control) received 5% dimethylsulfoxide (DMSO) at 5 ml/kg, while groups B -D received CDME at 50, 100 and 200 mg/kg, respectively. All treatments were administered orally and once daily for 28 consecutive days. The haematological profile, liver and kidney function tests, lipid profile as well as antioxidant status were evaluated. The 50 mg/kg extract significantly (P<0.05) reduced the red blood cell count, packed cell volume, haemoglobin, but had no effect on leucocytic profile of rats. There was no significant difference (P>0.05) in leucocyte profile between the control and groups given the extract. At 200 mg/kg, CDME significantly (P<0.05) increased total protein, alkaline phosphatase (ALP) and aspartate transaminase (AST) compared to the control group. Triglyceride, high density lipoprotein (HDL-C) and very low density lipoprotein (VLDL-C) were significantly (P<0.05) increased by the extract at both 100 and 200 mg/kg while low density lipoprotein (LDL-C) was significantly (P<0.05) decreased by the extract at those doses compared to the control. Urea level was significantly higher (P<0.05) in rats dosed at 100mg/kg while creatinine levels was not increased by the extract. The antioxidants Superoxide dismutase and glutathione reductase were significantly (P<0.05) higher in rats at all doses of the extract while serum catalase level was significantly lower (P<0.05). We conclude that Combretum dolichopetalum could cause a reduction in erythrocyte parameters and should be administered with caution in anaemic conditions as well as in liver diseases.