الفهرس 
Introduction and aim of workOnly 14 pages are availabe for public view
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Abstract
This study was performed to elucidate the effect of type I diabetes mellitus and its treatment with insulin alone or insulin in combination with chromium picolinate on improving the antioxidant and glycemic status as well as the effect of these drugs on the levels of Glutathione peroxidase (GPx) gene expression.
Rats were injected with streptozotocin at a dosage of 60 mg/kg body weight after overnight fasting for diabetes induction, and then rats were treated with insulin alone in a dose rate of 1 IU/100 gm body weight subcutaneously or insulin and fed on diets supplemented with chromium picolinate (400 mcg/kg of diet).
After the end of the experiment (6 weeks) the animals were anesthetized for collection of blood and liver samples which was used to determine glucose and insulin level in serum, malondialdehyde (MDA) level in serum and liver, superoxide dismutase (SOD) activity and reduced glutathione (GSH) level in erythrocyte lysate and liver and glutathione peroxidase gene expression in hepatic tissue.
STZ injection increased glucose and decreased insulin level in serum, increased MDA content of both serum and liver and decreased reduced glutathione concentration and superoxide dismutase activity in erythrocyte lysate and liver, as well as lowered Glutathione Peroxidase (GPx) gene expression in liver compared to the control group. Insulin injection decreased glucose and increased insulin level in serum, decreased MDA content of both serum and liver and increased reduced glutathione concentration and superoxide dismutase activity in erythrocyte lysate and liver, as well as normalized Glutathione Peroxidase (GPx) gene expression in liver, while supplementation of chromium picolinate and insulin decreased glucose and increased insulin level in serum, decreased MDA content of both serum and liver, reaching normal concentration and increased reduced glutathione concentration and superoxide dismutase activity in erythrocyte lysate and liver.
Glutathione Peroxidase (GPx) gene expression in liver was significantly increased compared to the control group and insulin treated group.
The obtained result indicated that, chromium picolinate has antioxidant properties which demonstrated through increasing the activity of SOD and GSH level. At the same time, the gene expression level of GPx was upregulated in the liver. It also decreased lipid peroxidation which represented by MDA that indicated its ability for scavenging ROS. These previous results revealed that chromium has antioxidant effect beyond its role as a cofactor for insulin function. Combination of both insulin and chromium picolinate improved glycemic state and adverse effects and complications resulting from diabetes through enhancement antioxidant mechanisms than insulin alone.