The Effects of Vitamin C on Lipoproteins, Apo A-I, Apo B, Malondialdehyde(MDA) and the Assessment of its Interaction with Copper in Hyperlipidemic Patients

Epidemiological studies showed protective effect of vitamin C on improvement of serum lipoproteins and decrease of coronary heart disease(CHD), but its interaction with copper absorption and metabolism is also reported. The aim of the present study was to determine the effects of vitamin C on lipoproteins and its interaction with copper in hyperlipidemic patients. In a double blind placebo trial of parallel design study, 36 hyperlipidemic patients(total cholesterol(TC) and triglyceride(TG) greater than 200 mg/dl) were randomly assigned into two groups to receive daily 500mg vitamin C (study group) or placebo(control group) for 10 weeks. Fasting blood samples were collected at the beginning and at the end of the period. TG, TC, LDL-C, HDL-C were measured enzymatically, apo B and apo A-I immunoturbidometerically, MDA and vitamin C colorimetrically, serum copper via atomic absorption spectroscopy and plasma ceruloplasmin(CP) enzymatically. The obtained data which were analyzed by t-test, paired t-test, chi square and ANOVA, showed that in vitamin C group there was a significant decrease at the end of study in TC, apo B and MDA compared to initial value(P=0.004, P=0.005, P<0.01 respectively). There was a significant increase in blood vitamin C compared to initial value(P=0.001) and compared to control group(P=0.01). There was no significant change in TG, apoA-I, LDL-C and HDL-C, copper and CP during the study. It seemed that LDL particle size became greater due to apo B decrease but LDL-C did not change during the study. Therefore, it can be concluded that 500 mg vitamin C for 10 weeks in hyperlipidemic patients have desirable effects on TC, apo B and possibly LDL size and can decrease the risk of CHD without any interaction with body copper status.