In Vivo Subacute Toxicity and Antidiabetic Effect of Aqueous Extract of<i>Nigella sativa</i>

Abstract

<i>Context. Nigella sativa</i> seeds are usually used as traditional medicine for a wide range of therapeutic purposes. <i>Objective.</i> To investigate the subacute toxicity of NS aqueous extract and select its lowest dose to study its antidiabetic effect. <i>Methods.</i> 5 AqE.NS doses (2, 6.4, 21, 33, and 60 g/Kg) were daily administered to mice by gavage. Biochemical parameters measurements and histological study of the liver and the kidney were performed after 6 weeks of supplementation. Thereafter, and after inducing diabetes by alloxan, rats were treated by 2 g/Kg of AqE.NS during 8 weeks. Metabolic parameters were measured on sera. A horizontal electrophoresis of plasmatic lipoprotein was conducted. Glycogen, total lipids, and triglycerides were measured in the liver. TBARS were evaluated on adipose tissue, liver, and pancreas. <i>Results.</i> AqE.NS showed no variation in urea and albumin at the 5 doses, but hepatotoxicity from 21 g/Kg was confirmed by histopathological observations of the liver. In diabetic rats, AqE.NS significantly decreased glycemia, TG, T-cholesterol, LDL-c, and TBARS and showed a restored insulinemia and a significant increase in HDL-c. Results on the liver indicated a decrease in lipids and a possible glycogenogenesis. <i>Conclusion.</i> AqE.NS showed its safety at low doses and its evident antihyperglycemic, antihyperlipidemic, and antioxidant effect.