Effect of combined supplementation with alpha-tocopherol, ascorbate, and beta carotene on low-density lipoprotein oxidation.
Effect of combined supplementation with alpha-tocopherol, ascorbate, and beta carotene on low-density lipoprotein oxidation.
复制标题
联合补充α-生育酚、抗坏血酸和β-胡萝卜素对低密度脂蛋白氧化的影响。
DOI：
10.1161/01.cir.88.6.2780
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发表时间：
1993
期刊：
影响因子：
37.8
通讯作者：
Grundy,SM
中科院分区：
文献类型：
--
作者：
Jialal,I;Grundy,SM
背景越来越多的数据支持氧化低密度脂蛋白（Ox-LDL）的促动脉粥样硬化作用。抗坏血酸、α-生育酚和 β 胡萝卜素等抗氧化微量营养素可以通过饮食措施有利地控制其水平，而不会产生副作用，可能是抑制 LDL 氧化的安全方法。事实上，体外研究表明，所有三种抗氧化剂都可以抑制 LDL 氧化。本研究旨在确定联合补充 α-生育酚、抗坏血酸和 β 胡萝卜素对 LDL 氧化的安全性和抗氧化作用。 方法和结果 联合补充 α-生育酚 (800 IU/天) 加抗坏血酸 (1.0 g/天) 和 β 胡萝卜素 (30 mg/天) 对铜催化 LDL 氧化的影响进行了随机、对两组 12 名男性受试者进行为期 3 个月的安慰剂对照研究。在基线和 3 个月时获取血样，用于检测脂蛋白谱、抗氧化剂水平和 LDL 分离。安慰剂和联合抗氧化疗法均未产生任何副作用或对血浆脂蛋白谱产生不利影响。与安慰剂相比，联合抗氧化疗法导致血浆抗坏血酸和脂质标准化α-生育酚和β-胡萝卜素水平显着增加（分别为2.6、4.1和16.3倍）。在基线时，硫代巴比妥酸反应物质 (TBARS) 测定和共轭二烯的形成证明，LDL 氧化的时程曲线和动力学没有显着差异。然而，在 3 个月时，联合补充导致滞后期延长两倍，氧化率降低 40%。联合抗氧化剂组还与仅接受 800 IU α-生育酚的组进行了比较。尽管联合抗氧化剂组的抗坏血酸和β-胡萝卜素水平显着高于单独补充α-生育酚的组，但两组之间的LDL氧化动力学没有显着差异。 结论联合补充抗坏血酸、β-胡萝卜素和α-生育酚在抑制LDL氧化方面并不优于单独补充高剂量的α-生育酚。因此，在未来涉及抗氧化剂的冠状动脉预防试验中，α-生育酚疗法应受到青睐。
BACKGROUNDData continue to accumulate supporting a proatherogenic role for oxidized low-density lipoprotein (Ox-LDL). Antioxidant micronutrients such as ascorbate, alpha-tocopherol, and beta carotene, levels of which can be favorably manipulated by dietary measures without side effects, could be a safe approach in inhibiting LDL oxidation. In fact, in vitro studies have shown that all three antioxidants can inhibit LDL oxidation. The present study was undertaken to ascertain both the safety and antioxidant effect of combined supplementation with alpha-tocopherol, ascorbate, and beta carotene on LDL oxidation.METHODS AND RESULTSThe effect of combined supplementation with alpha-tocopherol (800 IU/d) plus ascorbate (1.0 g/d) and beta carotene (30 mg/d) on copper-catalyzed LDL oxidation was tested in a randomized, placebo-controlled study in two groups of 12 male subjects over a 3-month period. Blood samples for the lipoprotein profile, antioxidant levels, and LDL isolation were obtained at baseline and at 3 months. Neither placebo nor combined antioxidant therapy resulted in any side effects or exerted an adverse effect on the plasma lipoprotein profile. Compared with placebo, combined antioxidant therapy resulted in a significant increase in plasma ascorbate and lipid standardized alpha-tocopherol and beta carotene levels (2.6-, 4.1-, and 16.3-fold, respectively). At baseline, there were no significant differences in the time course curves and kinetics of LDL oxidation as evidenced by the thiobarbituric acid reacting substances (TBARS) assay and the formation of conjugated dienes. However, at 3 months, combined supplementation resulted in a twofold prolongation of the lag phase and a 40% decrease in the oxidation rate. The combined antioxidant group was also compared with a group that received 800 IU of alpha-tocopherol only. Although the combined antioxidant group had significantly higher ascorbate and beta carotene levels than the group supplemented with alpha-tocopherol alone, there were no significant differences between the two groups with respect to LDL oxidation kinetics.CONCLUSIONSCombined supplementation with ascorbate, beta carotene, and alpha-tocopherol is not superior to high-dose alpha-tocopherol alone in inhibiting LDL oxidation. Hence, alpha-tocopherol therapy should be favored in future coronary prevention trials involving antioxidants.