Potential antidiabetic effect of ethanolic and aqueous-ethanolic extracts of Ricinus communis leaves on streptozotocin-induced diabetes in rats

Abstract

Recently, herbal drugs and their bioactive compounds have gained popularity in the management of diabetes mellitus (DM), which has become an epidemic disease all over the world and is especially prevalent in the Kingdom of Saudi Arabia (KSA). This study aimed to investigate the antidiabetic effect of ethanolic and aqueous-ethanolic extracts of wild Ricinus communis (R. communis) leaves in streptozotocin (STZ) induced diabetic rats. Diabetic rats were administered orally with the mentioned extracts at doses of 300 and 600 mg/kg/BW for 14 days, and the obtained results of different biochemical parameters were compared with normal control, diabetic control and standard drug glibenclamide (5 mg/kg/BW). The obtained results revealed a remarkable and significantly (P < 0.05) reverse effect of the body weight loss, observed when diabetic rats were treated with ethanol and aqueous-ethanol extracts at 300 mg/kg/BW. Administration of the ethanol extract at 600 mg/kg/BW significantly (P < 0.05) reduced the blood glucose level. A significant increase in the AST, ALT and ALP levels (P < 0.05) was observed in the diabetic control and in the experimental groups with glibenclamide which was also significantly (P < 0.05) lowered after treatment with extracts at special doses. Total proteins, albumin, total bilirubin, direct bilirubin, creatinine and urea were also investigated and compared to the corresponding controls. We showed that administration of R. communis extract generally significantly (P < 0.05) ameliorated the biochemical parameters of diabetic rats. Also, the changes in serum electrolyte profile were assessed and the results demonstrate that administration of extracts at concentration of 600 mg/kg/BW generally inhibits the alteration maintain their levels. The obtained data imply the hypoglycemic effects of this plant, which may be used as a good alternative for managing DM and therefore validating its traditional usage in KSA.

Keywords: Antidiabetic activity; Blood glucose level; Electrolytes; Liver enzymes; Ricinus communis; Streptozotocin.

Figure 1. The effect of Ricinus communis leaves extracts on the blood glucose in STZ induced diabetic rats after 2 weeks of treatment.

STZ, Control diabetic rats; STZ + EE300 mg/kg/BW, STZ + Ethanol extract at 300 mg/kg/BW; STZ + AE-300 mg/kg/BW, STZ + Aqueous-ethanol at 300 mg/kg/BW; STZ + E600 mg/kg/BW, STZ + Ethanol at 600 mg/kg/BW; STZ + AE600 mg/kg/BW, STZ + Aqueous-ethanol at 600 mg/kg/BW. *Values are statistically significant at p < 0.05. **Values are statistically significant at p < 0.01. The data were analysed using the parametric method, ANOVA followed by Tukey’s post-hoc test.