Preventive role of Withania somnifera on hyperlipidemia and cardiac oxidative stress in streptozotocin induced type 2 diabetic rats
Purpose: The present study was intended to investigate the preventive role of Withania somnifera (WS) on hyperlipidemia and oxidative stress in the heart of streptozotocin (STZ)-induced type 2 diabetic rats.
Methods: Single intraperitoneal injection of STZ (100 mg/kg) was given to 2 days rat pups to induce type 2 diabetes mellitus. Diabetes was confirmed 90 days after the administration of STZ by measuring blood glucose level. WS (200 and 400 mg/kg) was administered orally once a day for 5 weeks after the confirmation of diabetes. Glucose, lactate dehydrogenase (LDH), creatinine kinase (CK), total cholesterol (TCh), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), verylow density lipoprotein cholesterol (VLDL-C) and markers of oxidative stress parameters like lipid peroxidation (LPO), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) were evaluated in the heart of type 2 diabetic rats.
Results: Oral administration of WS for 5 weeks resulted in a significant (P<0.001) reduction in glucose, LDH, CK, TC, TG, LDL-C, VLDL-C levels with significant elevation of HDL-C levels. On the other hand, WS treated diabetic rats significantly (P<0.01-P<0.001) reduced the elevated levels of LPO, increased levels of antioxidant enzymes (i.e, GSH, GPx, GR, GST, SOD and CAT).
Conclusion: These findings propose the role of hyperlipidemia and cardiac oxidative stress in type 2 diabetic rats and suggested protective effect of WS in this animal model.
Keywords: Withania somnifera; Hyperlipidemia; Oxidative stress; Streptozotocin; Type 2 diabetes