Biochemical Study on the Effect of Coffee and Cinnamon on the Streptozotocin induced Diabetes in Rats

Abstract

Type 2 diabetes mellitus is a major endocrine disorder and a deadly disease in human beings. According to the recent estimations, the prevalence of diabetes in the world, would reach to 552 million people in 2030. This disease is characterized by hyperglycemia, atherosclerosis, and abnormal lipid profile and also induces several chronic complications such as retinopathy, nephropathy, and neuropathy that results in burdening heavy load on these patients and society. Dyslipidemia, a main risk factor for cardiovascular diseases as well as increase in generation of reactive oxygen species (ROS) and occurrence of oxidative stress which results in destruction of insulin producing β-cells in pancreatic langerhans islets, all have critical role in pathogenesis and progression of diabetes mellitus. Although chemical antidiabetic drugs such as biguanides and sulphonylureas are available at the present time, they might cause several side effects e.g. hypoglycemia, liver toxicity, dyslipidemia and increase in blood pressure. Since using of medicinal plants is more financial, and they have different varieties of effective compounds as well as lower side effects in comparison to synthetic drugs and also because of recommendations of world health organization (WHO), in recent years, there has been renewed interest in using hypoglycemic traditional plants. There are many medicinal herbs which have been recommended for the treatment of diabetes. The main objective of this study was to deduce of better methods of herbal treatment and comparing treatments by cinnamon, green and black coffee alone or by mixing herbs together on the STZ induced diabetes in rats. For rats administration of single herbs, 100 ml of boiling distilled water are poured to 10 grams of each natural compound (black , green coffee or cinnamon) was lift to cool then each rat is administered by gavage for 90 days. For rats administration of combined herbs, 50 ml of boiling distilled water are poured to 10 grams of each natural compound (black , green coffee and cinnamon) was lift to cool then each rat is administered by gavage for 90 days. Sixty four female albino rats were weighed and divided into eight equal groups; 6 groups were treated orally one time daily for 90 days. Group 1: group serves as untreated controls. Group 2: group was rendered control STZ induced diabetic rats. Group 3: group was rendered STZ induced diabetic rats administered black coffee extract by gavage. Group 4: group was rendered STZ induced diabetic rats administered green coffee extract by gavage. Group 5: group was rendered STZ induced diabetic rats administered cinnamon extract by gavage. Group 6: group was rendered STZ induced diabetic rats administered black coffee and cinnamon extracts by gavage. Group 7: group was rendered STZ induced diabetic rats administered green coffee and cinnamon extracts by gavage. Group 8: group was rendered STZ induced diabetic rats administered black ,green coffee and cinnamon extracts by gavage. After 3 months from the treatments, rats of each group were fasted overnight before blood sampling and sacrificed under diethyl ether anesthesia. The following parameters were estimated: serum glucose, serum insulin, serum total cholesterol, triacylglycerols (TAG), high density lipoprotein-cholesterol (HDL-cholesterol) , blood urea nitrogen, creatinine , uric acid , malondialdehyde (MDA) , paraoxinase (PON) , reduced glutathione (GSH), nitric oxide ,low density lipoprotein- cholesterol , very low density lipoprotein- cholesterol and homeostasis model assessment of insulin resistance (HOMA IR) were calculated.