Nagyová A, Mongiellová V, Krivosíková Z, Blazícek P, Spustová V, Gajdos M, Dzúrik R
Institute of Preventive and Clinical Medicine, Bratislava, Slovak Republic.
Physiol Res. 2002;51(5):457-64.
The decreased oxidizability of plasma lipoproteins is related to the increased vitamin E intake and its association with a relatively lower incidence of coronary heart disease has been proposed. We investigated the effect of the in vivo vitamin E supplementation on the oxidizability of serum lipids in patients with ischemic heart disease and a moderate hypercholesterolemia. Thirty-two patients (16 males and 16 postmenopausal women) participated in this placebo-controlled, randomized trial. They were treated with 400 mg vitamin E/day for 6 weeks. The copper-induced serum lipid oxidizability ex vivo was assessed by measuring conjugated diene formation at 245 nm. We also measured vitamin E, malondialdehyde (MDA) and uric acid concentrations in the plasma. Because of observed significant differences in parameters of serum lipid oxidizability (lag time and maximal rate of oxidation), plasma alpha-tocopherol and MDA levels between male patients and postmenopausal women supplemented with vitamin E, the results were compared between both genders. Six weeks of vitamin E supplementation significantly increased plasma vitamin E levels (by 87 %) in male patients but in postmenopausal women only by 34 %. Concomitantly with increased plasma levels of vitamin E the decrease in plasma MDA levels was observed in male patients (decrease by 20 %; p=0.008), but in postmenopausal women the decrease did not attain statistical significance. Plasma uric acid levels were not apparently changed in placebo or vitamin E supplemented groups of patients. The changes in ex vivo serum lipid oxidizability after vitamin E, supplementation have shown a significantly prolonged lag time (by 11 %; p=0.048) and lowered rate of lipid oxidation (by 21 %; p=0.004) in male patients in comparison with postmenopausal women. Linear regression analysis revealed a significant correlation between plasma vitamin E levels and the lag time (r=0.77; p=0.03) and the maximal rate of serum lipid oxidation (r=-0.70; p=0.05) in male patients. However, in postmenopausal women the correlations were not significant. We conclude that 400 mg vitamin E/day supplementation in patients with ischemic heart disease and a moderate hypercholesterolemia influenced favorably ex vivo serum lipid oxidation of male patients when compared with postmenopausal women. The observed differences between both genders could be useful in the selection of the effective vitamin E doses in the prevention of coronary heart disease.
血浆脂蛋白氧化能力降低与维生素E摄入量增加有关，并且有人提出这与冠心病发病率相对较低存在关联。我们研究了体内补充维生素E对缺血性心脏病合并中度高胆固醇血症患者血清脂质氧化能力的影响。32名患者（16名男性和16名绝经后女性）参与了这项安慰剂对照的随机试验。他们接受了为期6周、每日400毫克维生素E的治疗。通过测量245纳米处共轭二烯的形成来评估铜诱导的离体血清脂质氧化能力。我们还测量了血浆中维生素E、丙二醛（MDA）和尿酸的浓度。由于观察到补充维生素E的男性患者和绝经后女性在血清脂质氧化能力参数（滞后时间和最大氧化速率）、血浆α-生育酚和MDA水平上存在显著差异，因此对两性结果进行了比较。补充维生素E六周后，男性患者血浆维生素E水平显著升高（升高87%），而绝经后女性仅升高34%。与血浆维生素E水平升高同时，男性患者血浆MDA水平下降（下降20%；p = 0.008），但绝经后女性的下降未达到统计学意义。安慰剂组或补充维生素E组患者的血浆尿酸水平无明显变化。与绝经后女性相比，补充维生素E后离体血清脂质氧化能力的变化显示男性患者的滞后时间显著延长（延长11%；p = 0.048），脂质氧化速率降低（降低21%；p = 0.004）。线性回归分析显示男性患者血浆维生素E水平与滞后时间（r = 0.77；p = 0.03）以及血清脂质最大氧化速率（r = -0.70；p = 0.05）之间存在显著相关性。然而，在绝经后女性中，这些相关性不显著。我们得出结论，与绝经后女性相比，缺血性心脏病合并中度高胆固醇血症患者每日补充400毫克维生素E对男性患者的离体血清脂质氧化有有利影响。观察到的两性差异可能有助于在预防冠心病时选择有效的维生素E剂量。
