Ameliorative effects of aqueous and methanol extracts of Hibiscus sabdariffa calyx (Zobo) on haematology and lipid profile of Wistar rats exposed to lead-induced toxicity

Hibiscus sabdariffa calyx extract and lead toxicity

Abstract

Abstract

Exposure to lead toxicity has been reported to cause harmful effects to humans and animals, with the most deleterious effects on the haematopoietic cells. In this study, therefore, the potential ameliorative effects of a local plant extract, Hibiscus sabdariffa (Zobo), on lead toxicity were evaluated. Forty-two 6-week-old male Wistar rats with an average weight of 140g were used for the study. The rats were divided into 7 groups of 6 rats per group. Group A, served as the control, received only distilled water. Group B received 100 mg/kg of lead acetate only, while Group C received 100 mg/kg of lead acetate and 200 mg/kg of aqueous extract of Hibiscus sabdariffa. Group D received 100 mg/kg of lead acetate and 400 mg/kg of aqueous extract of Hibiscus sabdariffa, Group E received 100 mg/kg of lead acetate and 50 mg/kg of Hibiscus sabdariffa methanol extract while Group F received 100 mg/kg of lead acetate and 100 mg/kg of Hibiscus sabdariffa methanol extract, Group G was given 100 mg/kg of lead acetate and 100 mg/dL of ascorbic acid, concurrently, per os per day for 28 days by gastric gavage. Blood samples were collected at days 14 and 28 for haematology, erythrocyte osmotic fragility and plasma biochemistry. The results showed that 200 mg/kg of aqueous extracts and 50 and 100 mg/kg of methanol Hibiscus sabdariffa ameliorated anaemia (haematinic activity), lymphocytosis and increased erythrocytes' osmotic fragility caused by both acute and subacute lead toxicity. The results from plasma biochemistry confirmed the antilipidaemic and anticholesterolaemic effects of the extracts. In conclusion, the study demonstrated that lead toxicity induced anaemia, dyslipidaemia and hypercholesterolaemia, which were ameliorated by low doses of Hibiscus sabdariffa calyx (Zobo) extracts.