血浆和低密度脂蛋白中α-生育酚含量之间缺乏相关性，但γ-生育酚和类胡萝卜素的相关性较高。

Lack of correlation between the alpha-tocopherol content of plasma and LDL, but high correlations for gamma-tocopherol and carotenoids.

作者信息

Ziouzenkova O, Winklhofer-Roob B M, Puhl H, Roob J M, Esterbauer H

机构信息

Institute of Biochemistry, University of Graz, Austria.

出版信息

J Lipid Res. 1996 Sep;37(9):1936-46.

PMID:8895059

Abstract

In 59 healthy human subjects (37 male and 22 female) the concentrations of the lipid-soluble antioxidants alpha- and gamma-tocopherol, alpha- and beta-carotene, lycopene, cryptoxanthin, canthaxanthin, and lutein + zeaxanthin were determined in plasma (mumol/L) and in isolated low density lipoproteins (LDL) (mumol/mmol cholesterol). Plasma alpha-tocopherol concentrations were significantly correlated with plasma total cholesterol concentrations (r2 = 0.51, P < 0.0001) yet not with the LDL alpha-tocopherol content (r2 = 0.05, ns). Plasma gamma-tocopherol concentrations were weakly correlated with plasma total cholesterol (r2 = 0.12, P < 0.003) and both absolute and cholesterol standardized plasma gamma-tocopherol concentrations correlated strongly with the LDL gamma-tocopherol content (r2 = 0.58 and r2 = 0.72, respectively). In contrast, carotenoid concentrations did not correlate with cholesterol concentrations, but their LDL content correlated significantly with the respective plasma concentrations (r2 = 0.67 to 0.92, all P < 0.0001). In a subgroup of study subjects (n = 13) the distribution of vitamin E and carotenoids among LDL was calculated. The proportion of plasma alpha- and gamma-tocopherol found in LDL was 48 +/- 7 (range, 36-61%) and 41 +/- 7%, respectively, suggesting that LDL was in most of these subjects not the main carrier for these antioxidants. The lipophilic carotenoids, however, were predominantly carried by LDL (e.g., beta-carotene: 87 +/- 10%), whereas the proportion of the more polar ones carried by LDL was much smaller (e.g., lutein + zeaxanthin: 36 +/- 6%). The results of this study show that plasma alpha-tocopherol concentrations are not predictive for the alpha-tocopherol content of LDL in nonsupplemented individuals. This finding could have implications in interpreting the cause of the inverse relationship between plasma alpha-tocopherol and risk of atherosclerosis.

摘要

在59名健康人体受试者（37名男性和22名女性）中，测定了血浆（μmol/L）和分离的低密度脂蛋白（LDL）（μmol/mmol胆固醇）中脂溶性抗氧化剂α-生育酚、γ-生育酚、α-胡萝卜素、β-胡萝卜素、番茄红素、隐黄质、角黄素和叶黄素+玉米黄质的浓度。血浆α-生育酚浓度与血浆总胆固醇浓度显著相关（r2 = 0.51，P < 0.0001），但与LDL中α-生育酚含量无关（r2 = 0.05，无显著性差异）。血浆γ-生育酚浓度与血浆总胆固醇呈弱相关（r2 = 0.12，P < 0.003），血浆γ-生育酚的绝对浓度和胆固醇标准化浓度均与LDL中γ-生育酚含量密切相关（分别为r2 = 0.58和r2 = 0.72）。相比之下，类胡萝卜素浓度与胆固醇浓度无关，但其LDL含量与各自的血浆浓度显著相关（r2 = 0.67至0.92，均P < 0.0001）。在一组研究对象（n = 13）中，计算了维生素E和类胡萝卜素在LDL中的分布。LDL中血浆α-生育酚和γ-生育酚的比例分别为48±7（范围为36 - 61%）和41±7%，这表明在大多数这些受试者中，LDL不是这些抗氧化剂的主要载体。然而，亲脂性类胡萝卜素主要由LDL携带（例如，β-胡萝卜素：87±10%），而LDL携带的极性较强的类胡萝卜素比例则小得多（例如，叶黄素+玉米黄质：36±6%）。本研究结果表明，在未补充维生素的个体中，血浆α-生育酚浓度不能预测LDL中α-生育酚的含量。这一发现可能对解释血浆α-生育酚与动脉粥样硬化风险之间的负相关关系的原因具有重要意义。