APO B KINETICS PRE AND POST TRAINING IN ELDERLY ADULTS

本研究项目的主要目的是检验 运动训练对载脂蛋白B（apoB）动力学参数的影响 老年人的新陈代谢。 血浆低密度水平升高 脂蛋白胆固醇（LDL-C）和载脂蛋白B与 冠心病和心肌梗死的风险增加。 在 此外，血浆LDL-C和apoB存在年龄相关性增加 浓度的因此，心血管事件的风险增加 在老年人中，至少可以部分地解释为与年龄相关的 影响apoB代谢。 血浆中的ApoB水平是 它们的生产率以及它们的生产率 分解代谢 然而，apoB代谢的变化发生在 还没有很好地表征。 运动训练可降低LDL-C和apoB血浆水平 在健康成年人中的浓度。 然而， 运动引起的apoB浓度的有益变化 不清楚 具体而言，本项目的目的是澄清 运动训练是否会减少产量和/或增加产量 含有载脂蛋白B的脂蛋白的催化剂，从而增强 老年人的心血管风险特征。 在16周的运动训练前后，总胆固醇， 甘油三酯、血浆脂蛋白（VLDL、IDL、LDL）和载脂蛋白B 水平将被确定。 apoB的合成速率将是 通过测量运动训练前后的 静脉输注[1- 13 C]亮氨酸的掺入率 从血浆中分离的VLDL、IDL和LDL的apoB部分。 血浆和 apoB [1- 13 C]亮氨酸富集将通过气相色谱法测定 质谱，并用于解决多房室模型的 载脂蛋白B代谢先前由助理研究者开发。 本方案的结果将描述运动训练如何 调节含apoB脂蛋白的合成速率， 增加对老年人胆固醇代谢的了解。

The major objective of this research project is to examine the effects of exercise training on kinetic parameters of apolipoprotein B (apoB) metabolism in elderly adults. Elevated levels of plasma low density lipoprotein cholesterol (LDL-C) and apoB have been associated with an increased risk of coronary heart disease and myocardial infarction. In addition, there is an age related increase in plasma LDL-C and apoB concentrations. As such, the increased risk for cardiovascular events in the elderly may be explained at least in part, by the age related effect on apoB metabolism. ApoB levels in plasma are a function of the rate at which they are produced as well as the rate at which they are catabolized. Nevertheless, the changes in apoB metabolism occurring with aging have not been well characterized. Exercise training has been shown to decrease LDL-C and apoB plasma concentration in healthy adults. The underlying mechanism, however, for the exercise-induced salutary changes in apoB concentration remains unclear. Specifically, the purpose of this project is to clarify whether exercise training decreases production and/or increases catabolism of apoB containing lipoproteins, thus enhancing cardiovascular risk profile in elderly adults. Before and after sixteen weeks of exercise training, total cholesterol, triglyceride, plasma lipoprotein (VLDL, IDL, LDL) and apolipoprotein b levels will be determined. The synthesis rate of apoB will be determined before and after exercise training by measuring the incorporation rate of intravenously infused [1-13C] leucine into the apoB fraction of VLDL, IDL and LDL isolated from plasma. Plasma and apoB [1-13C] leucine enrichment will be determined by gas chromatography mass spectrometry, and used to solve the multi compartmental model of apoB metabolism previously developed by the associate investigators. The results of this protocol will characterize how exercise training regulated the synthetic rate of apoB containing lipoproteins and will add to understanding of cholesterol metabolism in the elderly.