ABSTRACT
UNLABELLED: Pterocarpus soyauxii Taub (Papilionaceae) is used in Cameroonian traditional medicine and pharmacopoeia to treat hypertension, diabetes, gastrointestinal parasitizes and cutaneous diseases. AIM OF THE STUDY: The present investigation was carried out to evaluate the safety of an aqueous stem bark extract of Pterocarpus soyauxii by determining toxicity after acute and sub-chronic oral administration in male and female rodents. MATERIALS AND METHODS: The acute toxicity test was conducted in mice. An aqueous extract of barks was administrated by gavage in single doses of 2.5-12.5 g/kg. General behaviour and mortality were examined for up to 7 days. The sub-chronic toxicity test was performed in rats. The plant extract was administered by daily gavage of 150-600 mg/kg for 42 days. Body weight, food and water intakes were followed weekly. Haematological, biochemical and organ parameters were determined at the end of the 42-day administration. RESULTS: In the acute study in mice, oral administration of the aqueous extract of Pterocarpus soyauxii caused dose-dependent general behaviour adverse effects and mortality. The no-observed adverse effect level (NOAEL) of the extract was 5.0 g/kg. The lowest-observed adverse effect level (LOAEL) was 7.5 mg/kg. Mortality increased with the dose, LD(50) was>10.75 g/kg for the mouse. In the sub-chronic study in rats, daily oral administration of the aqueous extract of Pterocarpus soyauxii did not result in death or significant changes in haematological or biochemical parameters, excepted increased hepatic catalase activity (P<0.05) at the dose of 600 mg/kg. No alteration was observed in body weight, food and water intake. Liver, kidney, lung and pancreas histopathology did not reveal morphological alteration. CONCLUSIONS: The results showed that the aqueous stem bark extract of Pterocarpus soyauxii Taub had very low toxicity in oral acute high dose administration and no toxicity in oral sub-chronic low dose administration and indicate that the plant could be considered safe for oral medication.
Subject(s)
Pterocarpus/toxicity , Administration, Oral , Animals , Behavior, Animal/drug effects , Cameroon , Ethnopharmacology , Female , Lethal Dose 50 , Male , Medicine, African Traditional , Mice , Mice, Inbred BALB C , No-Observed-Adverse-Effect Level , Plant Bark/toxicity , Plant Extracts/administration & dosage , Plant Extracts/toxicity , Plants, Medicinal/toxicity , Rats , Rats, WistarABSTRACT
AIM OF THE STUDY: The stem bark of Mammea africana Sabine (Guttiferae) is used in African rain forest to treat various diseases, including diabetes mellitus. We investigated whether Mammea africana extract induced hypoglycaemic activity in rats. MATERIALS AND METHODS: We tested the effects of acute (5h) and sub-acute (21 days) oral administrations of the CH(2)Cl(2)-MeOH stem bark extract of Mammea africana (19-300 mg/kg body weight) on blood glucose levels of normal and streptozotocin (STZ)-induced type 1 diabetic rats. The effects were compared with those of glibenclamide. RESULTS: Acute administration reduced blood glucose in the diabetic rats only (33.87%, P<0.01). Sub-acute treatment for 21 days also reduced blood glucose level in diabetic rats (73.29%, P<0.01). A reduction or stabilization in total serum protein, triglyceride, cholesterol and alanine amino transferase levels was also observed. No effect was observed on body weight loss but food and water intakes were significantly reduced (P<0.01) in diabetic rats. The maximal anti-diabetic effect was obtained with the dose of 75 mg/kg and was more important than that of glibenclamide. CONCLUSION: It can be concluded that extracts of Mammea africana exhibited a significant anti-hyperglycaemic activity and improved the metabolic alterations in STZ-diabetic rats. These results provide a rationale for the use of Mammea africana to treat diabetes mellitus and hypercholesterolemia.
