Lowering of resistance to oxidation of VLDLP and some subfractions of LDLPin patients with non-insulin-dependent diabetes mellitus

Aim. To investigate composition of very low density lipoproteins (VLDLP) an d some subfractions of low density lipoproteins (LDLP), and their resistanc e to oxidation in patients with non-insulin-dependent diabetes mellitus (NI DDM) varying in severity compared to healthy subjects. Materials and methods. 26 NIDDM patients and Id healthy controls. VLDLP and subfractions of LDLP were isolated by ultracentrifugation. The lipoprotein s were assayed for protein, cholesterol, initial products of lipid peroxida tion (LPO). After autooxidation of lipoproteins, fluorimetry examined the d egree of the oxidant modification. Results. The initial level of LPO products was elevated in VLDLP and light subfractions of LDLP in severe and moderate NIDDM patients. Even in mild NI DDM, resistance to oxidation of dense LDLP subfractions was low and continu ed to decrease with aggravation of the disease. High ratio cholesterol/ pro tein occurred in VLDLP and subfractions of LDLP from patients with severe N IDDM. Conclusion. it is shown that subnormal resistance to oxidation of LDLP dens e subfractions even in mild NIDDM is an informative diagnostic criterion of risk factor to develop atherosclerosis.