Ringseis Robert, Eder Klaus
Institut für Ernährungswissenschaften, Martin-Luther-Universität Halle-Wittenberg, Emil-Abderhaldenstraszligbeta;e 26, D-06108 Halle/Saale, Germany.
J Nutr. 2002 Dec;132(12):3732-5. doi: 10.1093/jn/132.12.3732.
This study was conducted to determine the interaction between the type of dietary fat (coconut oil or salmon oil) and the vitamin E concentration of the diet [10, 20, 40 or 240 mg alpha-tocopherol equivalents (alpha-toc)/kg] in relation to the concentration of 7beta-hydroxycholesterol (7beta-OH) in liver, plasma, LDL and erythrocytes of rats. In the rats whose diet contained salmon oil, the concentration of 7beta-OH was dependent on the dietary vitamin E concentration. Rats whose diet contained 10 mg alpha-toc/kg had significantly higher concentrations of 7beta-OH in all samples studied than those whose diet contained 20, 40 or 240 mg alpha-toc/kg. Increasing the dietary vitamin E concentration from 40 to 240 mg alpha-toc/kg did not reduce the concentration of 7beta-OH in any samples. In the rats whose diet contained coconut oil, the concentration of 7beta-OH was independent of the dietary vitamin E concentration in all samples. The study shows that insufficient vitamin E in the diet increases the formation of 7beta-OH in rats fed salmon oil, whereas a dietary vitamin E supply in excess of the requirement does not lower 7beta-OH concentrations compared with an adequate vitamin E supply.
本研究旨在确定膳食脂肪类型（椰子油或鲑鱼油）与膳食中维生素E浓度[10、20、40或240毫克α-生育酚当量（α-生育酚）/千克]之间的相互作用，以及其与大鼠肝脏、血浆、低密度脂蛋白（LDL）和红细胞中7β-羟基胆固醇（7β-OH）浓度的关系。在饮食中含有鲑鱼油的大鼠中，7β-OH的浓度取决于膳食维生素E浓度。饮食中含有10毫克α-生育酚/千克的大鼠，在所有研究样本中7β-OH的浓度显著高于饮食中含有20、40或240毫克α-生育酚/千克的大鼠。将膳食维生素E浓度从40毫克α-生育酚/千克提高到240毫克α-生育酚/千克，并未降低任何样本中7β-OH的浓度。在饮食中含有椰子油的大鼠中，所有样本中7β-OH的浓度均与膳食维生素E浓度无关。该研究表明，饮食中维生素E不足会增加食用鲑鱼油的大鼠体内7β-OH的形成，而与充足的维生素E供应相比，膳食中维生素E供应超过需求时并不会降低7β-OH的浓度。
