Acute and subacute toxicity profiling of methanol extract of Combretum dolichopetalum leaf in albino rats

The leaf of Combretum dolichopetalum is widely used in ethnomedicine to treat cases of diarrhea, inflammation and open wound. This study was hence, undertaken to determine the acute and subacute toxicity profile of the plant in albino rat model. A total of 426 g of dried and pulverized leaves of the plant was extracted with 2.5 L of 80% methanol by cold maceration method. A modified up-and-down method was employed for the oral acute toxicity study, with the extract administered at a maximum dose of 4000 mg/kg. For the subacute toxicity study, 18 rats were assigned into 3 groups (n = 6). Group A (control) received distilled water (5 ml/kg), while groups B and C were given 200 and 400 mg/kg of the extract, respectively. All the treatments were delivered orally for 28 days, after which blood samples were collected for hematology and serum biochemistry. Some vital organs were harvested for histological examination. The result of the acute toxicity recorded neither death nor morbidity even at the highest dose of the extract. For the subacute study, 400 mg/kg of the extract caused significant (p < 0.05) increase in total cholesterol and low density lipoprotein cholesterol (LDL-C); and significant (p < 0.05) decrease in high density lipoprotein cholesterol (HDL-C) in the treated rats when compared with the control. The histology slides showed only a mild fatty infiltration of hepatocytes in the group treated with 400 mg/kg of the extract. The results indicate a high safety index of the Combretum dolichopetalum leaf, however prolonged administration of high doses may cause hyperlipidemia.