Evaluation of antidiabetic activity of aqueous extracts of formulations produced from leafy vegetables and soumbara in rats

In Sub-Saharan Africa and more particularly in Côte d'Ivoire, many ethnobotanical studies have shown the pharmacological activities of the genera Leptadenia, Ocimum and Parkia against diabetes. Formulations made from leafy vegetables (Leptadeniahastata, Ocimumgratissimum) and soumbara are a very interesting and valuable natural source of valuable bioactive compounds that can be beneficial in the prevention of diabetes and its complications. In this context, the objective of this study is to evaluate the toxicity and to estimate the possible antidiabetic effect of the aqueous extracts of the various formulations on the weight and the glycaemia in rats rendered diabetic by alloxan. Before looking for the potential antidiabetic effect in vivo, an analysis of acute oral toxicity in rats was undertaken. The results showed that no mortality and no clinical signs of toxicity were observed in all rats. The lethal dose (LD50) obtained was greater than 5000 mg/kg bw, which made it possible to classify the aqueous extracts in category 5 of non-toxic substances by the oral route. After induction of diabetes, treatment with aqueous extracts of the different formulations was administered to diabetic rats orally at a daily dose of 50, 100 and 200 mg/kg for 28 days. The results obtained showed a marked increase in the body weight of the rats from -3.39% to 3.96%; 0.06% to 5.96% and 0.25 to 6.58% of baseline weights, respectively for doses of 50, 100 and 200 mg/kg bw and a significant drop in blood glucose (p < 0 .01) from 41.94 to 49.53% in rats treated with the aqueous extract at a dose of 50 mg/kg bw; from 56.43 to 65.03% in rats treated with the aqueous extract at a dose of 100 mg/kg bw and from 60.86 to 68.89% in rats treated with the aqueous extract at a dose of 200 mg/kg bw, compared to diabetic control rats. However, the F2 and F3 formulations at doses of 100 and 200 mg/kg bw showed better antidiabetic activity. In conclusion, the present study suggests that the aqueous extract of the F3 formulation at the dose of 200 mg/kg bw has a beneficial effect on the control of diabetes by protecting these rats against the massive loss of body weight and by significantly reducing the blood sugar.