The protective effect of Zataria multiflora Boiss. hydroalcoholic extract on TNF-α production, oxidative stress, and insulin level in streptozotocin-induced diabetic rats

Oxidative stress leads to reactive oxygen species (ROS) overproduction, which causes tissue injury in diabetic patients. The aim of this study was to evaluate the effects of Zataria multiflora extract on TNF-α, oxidative stress products, and insulin levels as well as lipid profile in diabetic rats. Rats were randomly divided into 6 groups of 10 animals. Diabetes was induced by a single injection of streptozotocin (STZ). Control and diabetic control rats orally received 1 mL/day of normal saline, whereas the other three groups received 250, 500 and 1000 mg/kg/day of Z. multiflora extract, and one non-diabetic group orally received 1000 mg/kg/day Z. multiflora extract, for 28 days. At the end of the treatment course, rats were anesthetized and their serum samples were analyzed for TNF-α, malondialdehyde (MDA), super oxide dismutase (SOD), total antioxidant capacity (TAC), lipid profile, total plasma protein, blood glucose, insulin, and liver enzymes levels. Our results showed that cholesterol, LDL, TG, MDA and TNF-α levels decreased, but HDL, SOD, TAC, and total protein increased significantly in the diabetic group receiving 1000 mg/kg Z. multiflora compared to the diabetic control group (P<0.05). Moreover, blood glucose level was significantly reduced following administration of different concentrations of Z. multiflora. Liver sections of diabetic rats treated with Z. multiflora 1000 mg/kg showed normal hepatocytes and restoration of liver architecture. Z. multiflora extract ameliorated oxidative stress, TNF-α serum level, lipid abnormality, blood glucose, and liver damage in rats with diabetes mellitus.