Iioxidative Stress And Iddm

Recent studies have indicated that ROS such as nitric oxide (NO), superoxide anion radical (02 ), and hydrogen peroxide (H202) are generated by MO in islets or induced in P-cells by cytotoxic cytokines secreted from immunocytes (3,4) (Fig. 1). It has been shown that the expression of inducible nitric oxide

Figure 1 A proposed mechanism of pancreatic (3-cell destruction by oxidative stress in autoimmune diabetes and drug-induced diabetes.

synthase (iNOS) is augmented in (3-cells of NOD mice (14). It has also been suggested that NO was induced by iNOS in the P-cells of human IDDM patients (15). These data indicate that oxidative stress may be one of the effector mechanisms of (3-cell destruction by infiltrating inflammatory cells in autoimmune diabetes.

It has previously been suggested that pancreatic p-cells are especially vulnerable to oxidative stress. In fact, p-cells are selectively destroyed by ROS-generating agents, streptozotocin (STZ) and alloxan (16-18). Such susceptibility to ROS is probably due to low levels of key enzymes scavenging ROS, such as superoxide dismutase (SOD), catalase, and glutathione peroxidase (19-22). Overexpression of Drosophila Cu/Zn SOD in P cells has been shown to confer resistance to alloxan-induced diabetes (23). Antioxidative agents such as nicotinamide (24,25) and vitamin E (26) have been shown to have protective effects against diabetes of NOD mice. Recently, it was reported that transgenic mice overexpressing iNOS in P cells develop insulin-dependent diabetes without insulitis (27). These results suggest that ROS and the antioxidative systems in p-cells play pivotal roles in the destruction of p-cells in the development of autoimmune diabetes.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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