Effect of Dietary Zinc Supplementation on Type 2 Diabetes Mellitus in Adult Male Albino Rats

Background: Diabetes mellitus [DM] is one of the most prevalent and dangerous diseases affecting public health worldwide. Frequent urine causes the body to lose zinc through hyperzincuria, hypozincemia, and reduced absorption, which results in zinc [Zn] insufficiency. Objective: The aim of this work was to study effect of dietary zinc administration on type 2 DM induced by alloxan in adult male albino rats fed on the high fructose diet [HFD]. Materials and Methods: The study included 32 adult male albino rats, divided into four equal groups: Group 1 [Control] received 1 ml normal saline/day by gavaging, Group 2 [Zn group] received 100 mg/kg/day Zn by gavaging, group 3 [diabetic], where diabetes was induced by alloxan as well as high fructose diet [HFD], Group 4 [diabetic with Zn supplement], where diabetic rats received 100 mg/kg/day Zn by gavaging. At the end of the experiment, rats were sacrificed, blood samples were obtained to measure fasting blood glucose [FBG], insulin level, glycated hemoglobin [HbAlc], homeostasis Model Assessment for Insulin resistance [HOM-IR], liver enzymes [Alanine transaminase [ALT], Aspartate transaminase [AST]], lipid profile, oxidative stress markers [Malonhydialdehyde [MDA], total antioxidant capacity [TAC], catalase [CAT] activity, Glutathione Peroxidase activity [GPX]] and serum creatinine. Histopathological study of liver and pancreatic tissues were performed. Results: Alloxan injection led to a significant increase of blood glucose, HbA1c, cholesterol, TG and LDL levels, liver enzymes and MDA while insulin, HDL, catalase and GPX levels were significantly decreased significantly compared to the control and ZN-supplemented groups. ZN supplementation led to a significant improvement of all laboratory parameters. The results were supported by the results of histological examinations. Conclusion: The study clarifies the beneficial effect of Zinc supplementation in diabetic rats as Zn improved the state of hyperglycemia, oxidative stress, dyslipidemia and liver dysfunction induced by DM.