The Study Of Antioxidant Status In Patients With Type 2 Diabetes Mellitus

Oxiidative stress is postulated to be increased in patients with diabetes mellitus. Accumulating evidence suggests that oxidative cell injury caused by free radicals contributes to the development of both macroangiopathy [2) and microangiopathy *3' occurring as complications of diabetes mellitus.Diabetes is well known to induce changes in the tissue content and activity of antioxidant enzymes.[41 l:>1On the other hand, extracellullar fluids lack protection by the antioxidant enzymes but contain various antioxidants that delay or inhibit the oxidative process by their presence at a much lower concentration than that of an oxidizable substrate. ' Recent studies have documented that hyperglycemia can cause generation of oxygen radicals, increased oxidative stress, and accumulation of lipid peroxidation products, such as malondialdehyde ( MDA ) in the blood of diabetic animals and patients.'7118'The relationship between oxidative stress and diabetic patients is still debated. This is largely due to the lack of goodtools to assay the level of oxidative stress. We have measured the serum concentrations of SOD, GSH-PX, MDA, T-AOS, and estimated AOR( SOD/MDA) in 174 Type 2 diabetic patients and 42 well-matched healthy subjects. The serum levels of SOD, T-AOS, GSH-PX were decreased in Type 2 DM. But MDA was increased. They all correlated well with the duration of disease and age. They all correlated with FPG and UMA except for GSH-PX. The increased MDA concentration was correlated with the degree of hyperlipidemia existed in Type 2 DM. We also found that in the early stage of the disease, the SOD and GSH-PX levels were not decreased. On the other hand, the GSH-PX was increased. This suggests an adaptive rather than a deleteriuos phenomenon. In the newly diagnosed patients with DKA, the SOD, GSH-PX levels were increased. There were also evidences suggesting that oxidative stress may be an important pathogenetic factor in the development of diabetic vascular complications.In conclusion, about this problem we need meta-analysis of the existing studies and we also need prospective randomized long-term clinical studies.