Toxicity Assessment of Cashew Nut Shell Methanol Extract on Hematology and Redox Status in Lungs and Liver of Wistar Rats

This study examines the effects of Cashew nut shell methanol extract (CNSME) on hematology, antioxidant parameters and histopathology in lungs and liver of rats. Forty-five male Wistar rats were used for the study, being divided into nine groups - A, B, C, D, E, F, G, H and I (five rats per group). The groups were orally intubated with corn oil (Control), 50, 100, 150, 200, 250, 300, 350 and 400 mg/kg of CNSME, respectively, every other day. After twenty-eight days, the rats were sacrificed under chloroform anesthesia. Blood was collected into EDTA bottles for determination of red blood cell (RBC) and mean corpuscular hemoglobin (MCH). Lungs and liver were excised and divided into two portions each. One portion was fixed in 10% formalin for histology, while the other was processed into homogenates for spectrophotometric assays of Superoxide dismutase (SOD) and catalase activities. The CNSME slightly reduced RBC, and increased MCH levels relative to controls. Both SOD and catalase were increased in lungs and liver, and reduced in liver and lungs, respectively by CNSME against controls. Rats given 250 and 400 mg/kg of CNSME showed degenerated pulmonary parenchyma in lungs, whereas liver showed heamoragic congestion in central venules, pyknotic hepatocytes and fibrosis. These lesions were not observed in controls and rats given 50 mg/kg of CNSME. In conclusion, high doses of cashew nut shell methanol extract could induce cytological damage in lungs and liver of rats via redox disruption, without any adversely effect on the red blood cell groups