[Susceptibility of LDL to lipid peroxidation in non-insulin-dependent diabetes mellitus with or without macroangiopathy].

Since oxidized LDL may play a role in the genesis of atheroma, which is the primary complication of non-insulin-dependent diabetes mellitus (NIDDM), we investigated whether the LDL of diabetic patients were more prone to oxidation than those of healthy controls. We therefore studied the susceptibility of LDL to oxidation by phenylhydrazine (LDL-PO) in NIDDM patients with or without macroangiopathy, and in controls. Results showed that the LDL of patients with macroangiopathy (n = 50) were more susceptible to oxidation than those of both NIDDM patients without vascular complications (n = 50) and controls (n = 50). In diabetic patients, there was a positive correlation between LDL-PO and the following parameters: total cholesterol, triglycerides, LDL cholesterol, apolipoprotein B. In contrast, there was no correlation between LDL-PO and the parameters of glycemic control (fasting glucose, HbAlc). After analyzing the composition of LDL, it appeared that LDL-PO values in diabetic patients were positively correlated with those of all LDL constituents. The increase in LDL-PO observed in the group of NIDDM patients with macroangiopathy could be a consequence of an increase in the LDL triglyceride content in these patients.