Background: Various medicinal plants have been studied using modern scientific approaches. These plants have a variety of properties and various biological components that can be used to treat various diseases. However, harmful effects of plants are common clinical occurrence. Objective:This study was designed to investigate toxicological assessment of acute and chronic methanol leaf extract of Vernonia bipontini Vatke (V.bipontini V) on blood, liver and kidney tissues of mice. Methods: Lethal dose (LD) at which 50% of experimental mice died and long term toxicity of methanolic leaf extract of V. bipontini V were determined. Some hematological and biochemical parameters were evaluated. Then, liver and kidney tissues of each animal were taken and processed for light microscopy. Results: Almost all mice treated with 800mg/kg methanol leaf extract of V. bipontini V showed swellings on the left part of abdominal region related to location of spleen, mild diarrhea and enlargement of spleen. The LD50 of the methanol leaf extract of V. bipontini V was 2130.6±1.5mg/kg. Treatment with 800mg/kg body weight of methanol leaf extract significantly decreased body, liver and kidney weights, red blood cells (RBC), haemoglobin (Hgb), mean cell haemoglobin (Mch), Mchc, platelet and significantly increased serum aspartate transferance (AST), vatanine tranferance(ALT) and alkaline phosphate (ALP) levels while 400mg/kg dose had no effect on these parameters. The reduced organ weights did not correlate with loss of body weight at 800mg/kg of methanol leaf extract of the plant. Light microscope observations of liver tissue of mice treated with 800mg/kg of the methanol leaf extract revealed dilated sinusoids, nuclear enlargement, lots of bi-nucleation of hepatocytes, peripheral cramped chromatin, shrinkages (single cell death) of hepatocytes, fragmentation of hepatocytes while no histopathological changes were observed in liver and kidney of mice treated at 400mg/kg. Kidney tissue sections of mice did not show significant histopathological changes at 400mg/kg. However, at 800mg/kg kidney sections showed increased cellularity of glomerulus, urinary space obliteration and enlarged macula densa. Conclusion: This study suggests that the methanol leaf extract may have been phytotoxic to liver that resulted in a rise in serum AST, ALT and ALP levels.

The present paper evaluates the acute and chronic toxicity of aqueous crude leaf extract of Vernonia bipontini Vatke (V. bipontini V) in mice model. Leaves of the plant were collected from Bale, Ethiopia, dried under shade, crushed into powder and soaked in water to yield the extract. Lethal dose of aqueous leaf extract of the plant was determined using nine groups of mice to which the aqueous leaf extracts of V. bipontini V was administered at doses ranging from 1250 to 3250mg/kg. All animals were closely observed for any physical and behavioral alterations for acute toxicity evaluation. For long-term toxicity evaluation, animals were subjected to oral administration of the extract at 400 and 800mg/kg, at 24 hours intervals for 45 days. The treated animals survived for 45 days. Body weights of the mice were recorded. Blood sample was collected from experimental and control groups for hematological studies and biochemical analysis on the 46 th day after anesthesia. The liver and kidney of each animal were taken and examined by light microscope for any anatomical abnormalities. The LD 50 was found to be 2500.62±5.24 mg/kg. The extract had no significant effect on liver and kidney weights, hematological (RBC, WBC, platelet, Hgb, Hct, Mcv, Mcv and L) and biochemical parameters such as liver AST, ALT and ALP; and kidney urea at all doses (P>0.05). Light microscope examination of liver and kidney tissue of mice treated with 400 and 800mg/kg of the extract did not show structural abnormalities. The results suggest that the extract of this plant may be safe, even when administered at a dose of 800mg/kg for 45 days. This is in agreement with the traditional claim of the water preparation of V. bipontini Vatke leaves.