[Plasma oxysterols and vitamin E concentrations and lipid profile in morbidly obese women]

Morbid obesity (BMI > or = 40 kg/m2) is accompanied by lipid disturbances which may be involved in the increased incidence of atherosclerosis, arterial hypertension and non-insulin-dependent diabetes mellitus. The aim of the study was to assess concentrations of total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, triglycerides (TG), products of cholesterol peroxidation--oxysterols, and the major lipophilic antioxidant--vitamin E, in morbidly obese women without coexisting diseases. The study was performed in 11 morbidly obese women (BMI 42.21 +/- 2.21 kg/m2) and 11 healthy volunteers (BMI 23.0 +/- 2.31 kg/m2). Obese women demonstrated higher concentrations of TG (2.03 +/- 0.78 vs. 0.99 +/- 0.37 mmol/l; p < 0.05), 7-ketocholesterol (7-K) (89.85 +/- 63.03 vs. 41.90 +/- 17.33 ng/ml; p < 0.05) and 7-hydroxycholesterol (7-OH) (456.04 +/- 199.22 vs. 132.37 +/- 53.96 ng/ml; p < 0.05), and lower HDL-cholesterol level (0.74 +/- 0.10 vs. 1.30 +/- +/- 0.17 mmol/l; p < 0.05) compared to the control group, while there were no significant differences between the two groups in concentrations of TC, LDL-cholesterol and vitamin E. Plasma vitamin E/(TC + TG) ratio was lower in obese women (6.42 +/- 2.61 vs. 10.76 +/- 4.57 mumol/mmol; p < 0.05). Tocoferols concentration correlated positively with TG (r = 0.45; p < 0.05) and negatively with 7-OH (r = -0.44; p < 0.05) levels. Moreover, concentration of 7-K correlated positively with the level of HDL (r = 0.54; p < 0.05). In conclusion, despite normal TC and LDL-cholesterol concentrations, there are disturbances in cholesterol peroxidation processes, with the rise in oxysterol levels and the decrease in vitamin E concentration in lipoproteins, which may be involved in the increased incidence of cardiovascular diseases in morbidly obese women.