ABOLISHING INCREASES IN INSULIN SENSITIVITY IN POSTMENOPAUSAL WOMEN

消除绝经后女性胰岛素敏感性的增加

• 批准号: 6303488
• 负责人: KATARINA T BORER
• 金额: $ 0.02万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-12-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6303488
• 关键词: adipose tissue; aging; clinical research; coronary disorder; disease /disorder proneness /risk; exercise; hormone biosynthesis; human subject; hypertension; insulin sensitivity /resistance; noninsulin dependent diabetes mellitus; obesity; postmenopause; women's health

Inactivity and excessive and inappropriate caloric intake stimulate development of visceral obesity that is associated with increased risks of type 2 (non-insulin-dependent) diabetes, hypertension, and coronary heart disease (CHD). Both exercise and dietary restriction have been successfully used as a means of body fat loss. In addition, exercise, with or without fat loss, can reduce risks of diabetes, hypertension, and CHD but its effects have not been consistent. In particular, there is little consensus regarding the effects of exercise intensity on either insulin sensitivity, body fat loss, or risks of hypertension and CHD. Our premise is that if exercise is to be used effectively to prevent or reduce different health risks or to be used as a tool in mechanistic analyses of hormone action, a better understanding of dose-dependent effects of exercise intensity is needed. Our pilot study, initiated two years ago, tested the hypothesis that exercise training at high walking intensities could increase basal pulsatile growth hormone (GH) secretion. The preliminary results supported this hypothesis, but in addition revealed that increases in training intensity attenuate increases in insulin sensitivity (assessed with an indirect measure of insulin sensitivity) that usually accompany exercise training. The goals of the present study are to (1) replicate in a larger group of 18 subjects the observed attenuation of insulin sensitivity at high training intensities with the more specific test of insulin sensitivity, Bergman's frequently sampled intravenous glucose tolerance test (FSIVGTT); (2) determine whether the effect of exercise intensity on insulin sensitivity is a consequence of, or independent of, changes in body fat mass and distribution; (3) replicate in a larger group of 18 subjects the observed increases in pulsatile GH secretion between 15 and 30 weeks of exercise training at high training intensities, and (4) collect some preliminary information on the effects of exercise intensity on plasma lipids (HDL-cholesterol , LDL-cholesterol, and triglycerides) which also constitute a risk of developing CHD.

无活动性和过度和不适当的热量摄入刺激内脏肥胖的发展，这与2型（非胰岛素依赖性）糖尿病，高血压和冠心病（CHD）的风险增加有关。 运动和饮食限制都已成功用作体内脂肪减少的手段。 此外，运动，无论有或没有脂肪流失，都可以降低糖尿病，高血压和冠心病的风险，但其影响并不一致。特别是，关于运动强度对胰岛素敏感性，体内脂肪的损失或高血压和CHD风险的影响几乎没有共识。我们的前提是，如果要有效地使用运动来预防或降低不同的健康风险或用作激素作用机械分析的工具，则需要更好地了解运动强度的剂量依赖性效果。 我们两年前发起的试点研究检验了以下假设：高步行强度下的运动训练可以增加基础搏动生长激素（GH）分泌。初步结果支持了这一假设，但此外表明，训练强度的提高减弱了通常伴随运动训练的胰岛素敏感性（以间接量的胰岛素敏感性评估）。本研究的目标是（1）在较大的18名受试者中复制，观察到的高训练强度下胰岛素敏感性的衰减具有更具体的胰岛素敏感性测试，伯格曼经常采样静脉葡萄糖耐受性测试（FSIVGTT）； （2）确定运动强度对胰岛素敏感性的影响是否是体内脂肪质量和分布变化的结果； （3）在一个较大的18名受试者组中复制，在高训练强度下，观察到的搏动性GH分泌增加了15至30周的锻炼训练，以及（4）收集一些有关运动强度对血浆脂质的影响的初步信息（HDL-胆固醇，LDL-cholestretol，LDL-胆固醇和triglycerides），这也构成了CHD的风险。