Biotechnology Journal International

The effects of black cumin seed or curcumin on blood glucose level, lipid peroxidation and gene expression of selected antioxidant enzymes and insulin like growth factor-1 (IGF-1) in diabetic rats were studied. Thirty two rats were assigned into four groups (8 rats in each). Rats of first group were non diabetic whereas rats of the second group were rendered diabetic by streptozotocin (STZ). Both groups served as negative and positive controls, respectively. Rats of the third and fourth groups were rendered diabetic and received oral Turmeric (1g/kg b.w.) and Black cumin seed (2g/kg b.w.), respectively for 6 weeks. Diabetic rats showed significant increase of blood glucose, thiobarbituric acid reactive substances (TBARS) and activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD) compared to the control non diabetic group. Gene expression of GPX and SOD was increased significantly in diabetic untreated rats compared to the control non diabetic group. The administration of either black cumin seed or curcumin to diabetic rats normalized significantly their blood sugar level and TBARS values and increased the activities of examined antioxidant enzymes. In addition, both plants treated rats showed significant increase in mRNA expression of IGF-1 and SOD compared to non-diabetic and diabetic untreated rats. Black cumin seed and curcumin was antidiabetic therapy, induced hypoglycemia by up-regulation of IGF-1 gene and ameliorate the diabetes induced oxidative stress via increasing the activities and gene expression of antioxidant enzymes.