Evaluation of Acute Toxicity and Hypoglycaemic and Hypolipidaemic Effects of Cyathula prostata (Linn.) Blume Weeds on Adult Rats
S. O. Ogbonnia *
Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
G. O. Mbaka
Department of Anatomy, Lagos State University College of Medicine, Ikeja, Lagos, Nigeria.
O. E. Akinsande
Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
D. A. Otah
Department of Physiology, College of Medicine of the University of Lagos, Idi-Araba, Lagos, Nigeria.
T. A. Ayeni
Department of Pharmacognosy, Faculty of Pharmacy, University of Lagos, Idi-Araba, Lagos, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Objectives: The study aimed at evaluating the acute toxicity and hypoglycaemic and hypolipidaemic effects of Cyathula prostata plant used locally in the treatment of various diseases including diabetes.
Materials and Methods: The toxicity of the extract was evaluated in Swiss albino mice by feeding the animals with the graded doses of the extract between 1.0 to 20.0 g/kg body weight (bwt) and continuously observed for the first 4 h, then hourly for the next 12 hand 6 hourly for the next 56 h (72 h, acute toxicity). Diabetes was induced in the male and female Wistar rats with alloxan monohydrate, at the dose of 150 mg/kg, dissolved in normal saline and administered intraperitoneally (i.p). The plasma glucose levels of the induced animals were monitored with a Glucometer (MERCK) after 72 h. The animals with plasma glucose level ≥200 mg/dl were classified as diabetic and were included in the study. The diabetic animals were randomly distributed into five groups of 5 animals each. The first group was normal not treated but received acacia 2% w/v solution. The second group was induced but not treated while the remaining four groups were treated with the reference drug, glibenclamide, (600 µg-1 kg bwt)/ the extract in graded doses of 75, 150 and 250 mg/kg bwt respectively for 30 days.
Results: The animals that received 20 g/kg bwt of the extract survived beyond 24 hrs, therefore the LD50 could be assumed to be above 20 g -1 kg bwt. The plasma level of alanine aminotransferase (ALT) was found to have significantly (p≤0.05) increased in the extract treated compared to the negative control whereas aspartate aminotransferase (AST) level showed marked decrease with dose. However, hepatic tissue histology at the highest extract dose treatment showed mild portal hepatitis with hepatocytes vacuolization and sinusoidal congestion. There were no significant changes (p≥0.05) in protein and creatinine levels. There were significant (p≤0.05) reduction in the plasma glucose, cholesterol, triglycerides and LDL levels while a significant increase in HDL levels was observed. The tissue histology of pancreas showed significant survivor of beta cells in the extract treated groups.
Conclusion: The extract was observed to have beneficial effect on alloxan-damaged pancreas as beta cells showed signs of recovery.
Keywords: Acute, toxicity, hypoglycaemic, hypolipidaemic, Cyathula prostata.