Supplementation of zinc mitigates the altered uptake and turnover of 65Zn in liver and whole body of diabetic rats.

Diabetes is a life threatening disease and its onset is linked with both environmental and genetic factors. Zinc metabolism gets altered during diabetes and results in many complications. The present study was designed to elucidate the effects of zinc supplementation on the biokinetics of (65)Zn in whole body, liver and its biodistribution in diabetic rats. The animals were divided into four groups viz; normal control; diabetic (single intraperitoneal injection of alloxan 150 mg/kg body weight); zinc treated (227 mg/l in drinking water); and diabetic + zinc treated. To carry out biokinetics study, each rat was injected intraperitoneally with 0.74 MBq radioactivity of (65)Zn following 4 weeks of different treatments and the radioactivity was determined by using a suitably shielded scintillation counter. Alloxan induced diabetic rats showed a significant decrease in both the fast (Tb(1)) and slow (Tb(2)) components of biological half-life of (65)Zn which, however, were normalized in whole body (P > 0.05) following zinc supplementation. In case of liver, Tb(2) component was brought back to the normal but Tb(1) component was not increased significantly. The present study indicates that the paucity of zinc in the tissues of the diabetic animals was due to decreased retention of tissue zinc as evidenced by increased serum Zn, hyperzincuria and increased rate of uptake of (65)Zn by the liver. Zinc supplementation caused a significant improvement in the retention of zinc in the tissues and is therefore likely to be of benefit in the treatment of diabetes.

Effectiveness of Zinc Supplementation on Lithium-Induced Alterations in Thyroid Functions.

Lithium is an integral drug used in the management of acute mania, unipolar and bipolar depression, and prophylaxis of bipolar disorders. Thyroid abnormalities have been associated with treatment with lithium. Zinc is an essential trace element that plays a role in several biological activities. Therefore, the present study was aimed at investigating the potential role of zinc in the thyroid gland following lithium administration to explore the role of zinc under such conditions. To achieve this goal, male Wistar rats (150-195 g) were divided into four groups: Group 1 animals were fed standard pellet feed and tap water ad lib; Group 2 rats were fed lithium in the form of lithium carbonate through diet at a concentration of 1.1 g/kg body weight; Group 3 animals received zinc treatment in the form of zinc sulfate (ZnSO4·7H2O) at a dose level of 227 mg/L mixed with drinking water of the animals; and Group 4 animals were given lithium and zinc in a similar manner as was given to the animals belonging to groups 2 and 4 respectively. The role of zinc on thyroid functions in lithium-treated rats was studied after 2, 4, and 8 weeks of different treatments. Zinc has been observed to have the capability to nearly normalize the altered 2-h uptake of 131I, biological and effective half-lives of 131I, and circulating T4 levels that were altered after lithium treatment. The present study concludes that zinc may be an effective agent in normalizing the adverse effects caused by lithium on thyroid functions.

Study of life style habits on risk of type 2 diabetes.

BACKGROUND: Diabetes mellitus has become one of the great epidemics of our time. AIM: Characterized by derangement of carbohydrate, protein and fat metabolism. Diabetic patients may have some other habits like drinking, smoking, lack of physical activity. In the present study, we have tried to study the effect of all these habits on lipid profile and antioxidative enzymes, i.e., catalase and superoxide dismutase. MATERIALS AND METHODS: Different kits and standard biochemical methods were used to estimate all these parameters. RESULTS: Diabetics as well as diabetic individuals who were engaged in drinking, smoking and regular physical exercise showed a significant rise in glucose levels compared to normal subjects. Similarly, cholesterol, triglyceride and high-density lipoprotein cholesterol levels and activity of catalase were found to be increased in all diabetic subjects, but that of superoxide dismutase decreased as compared to normal subjects. In all cases, exercise has a beneficial effect. Furthermore, females were more prone to destructive effects of diabetes than males. CONCLUSION: We can conclude that smoking and drinking by diabetic subjects further deteriorates the effects of diabetes, while regular physical exercise has beneficial effects.

Effect of zinc on hepatic drug metabolism under ethanol toxicity.

The effects of zinc on drug-metabolizing enzymes in the liver were examined in male Wistar rats following ethanol intoxication. Rats were orally fed 3 mL of 30% ethanol daily for either two, four, or eight weeks and were orally administered zinc sulfate (ZnSO4.7H2O) at a dose level of 227 mg/L. Levels of reduced glutathione (GSH) and the activities of cytochrome P-450, cytochrome b(5), NADPH cytochrome-C-reductase and glutathione-S-transferase (GST) were determined in liver after two, four, and eight weeks. Significant elevation was observed in the activities of the enzymes of the mixed function oxidase system in response to toxicity induced by ethanol at all the intervals. These effects of were ascribed to the enhanced activity of the microsomal ethanol oxidizing system and the associated increase in reactive oxygen species production. Zinc supplementation to these ethanol-intoxicated animals resulted in normalization of these elevated values significantly, but still they do not attain normal levels. Significant increase was observed in reduced glutathione content in animals after four and eight weeks of ethanol feeding, which appeared to be further elevated in combined zinc and ethanol treatment. Significant elevation in the activity of GST was illustrated on ethanol-fed animals at all the three treatment intervals. Furthermore, the activity of this enzyme was only moderately normalized following zinc treatment. This was accredited to the antioxidant potential of zinc, as well as its ability to induce metallothionein content, which provide protection against the toxic effects of ethanol. To conclude, zinc was able to normalize the effects of ethanol in the liver.