Introduction: The aim of the present study was to determine the susceptibility of lipids to Cu-induced peroxidation in diluted plasma and its relation with plasma lipids and lipoproteins in a group of healthy men. Materials and Methods: In 100 healthy men volunteers (age range 20-55 years with a mean of 36. 8± 10. 3 years), fasting plasma levels of lipoprotein (a) [Lp (a)], total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), and triglycerides (TG) were assayed. The Cu2+-induced lipid peroxidation was evaluated. Lipid oxidation was estimated by monitoring the change of conjugated dienes in the diluted plasma following the addition of Cu2+. The kinetic curves of the accumulation of lipid peroxide products were prepared, and a number of quantitative parameters including lag time, time of maximal oxidation rate (T-max), and maximal accumulation of absorbing products (OD-max) were evaluated. Results: The TG concentrations were positively correlated with lag time and T-max (r=0. 33, P < 0. 01 and r=0. 24, P < 0. 05) respectively. Also, TC and LDL-C were positively correlated with OD-max (r=0. 28, P < 0. 01 and r=0. 26, P < 0. 05 respectively), and HDL-C was negatively correlated (r=-0. 23, P < 0. 05) with T-max. No significant correlation was observed between other variables and lipid oxidizability parameters. Conclusions: Results of this research indicate that TG increased the resistance of LDL and VLDL against initiation of lipid oxidation. In addition, HDL-C induced the susceptibility of lipid oxidizability.

Objective: Diabetes is the most common metabolic disease. One of the most common problems in diabetic patients is atherosclerotic cardiovascular disease which induced by hyperlipidemia. Also there has been currently great interest in the potential contribution of oxidative stress in development of diabetes complications. The present study was performed to associate between lipid oxidizability and serum lipid levels in diabetic patients.Materials and Methods: In this study, 55 diabetic patients in Yazd Diabetes Research Center were chosen. Lipid oxidizability, HbA1c and serum lipid levels were analyzed in patients. Lipids were measured by enzymatic method. HbA1c was estimated by the ion exchange chromatography. The lipid oxidation procedure was performed by addition of CuCl2. The kinetics of conjugated dienes formation was monitored by spectrophotometer and parameters such as ODmax, Lag Time, Vmax and Tmax were analyzed.Result: In present study, there was no association between lipid oxidizability and serum lipids levels. Also there was no association between lipid oxidizability parameters and HbA1c.Conclusion: This study showed that high levels of blood lipids such as cholesterol and triglyceride do not have any effect on maximal amount of lipids peroxide products accumulation and maximal rate of oxidation during the lipid oxidation course.