REGULATION OF FAT METABOLISM DURING EXERCISE IN HUMANS

人体运动过程中脂肪代谢的调节

• 批准号: 2147792
• 负责人: MICHAEL G CARLSON
• 金额: $ 10.92万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-30 至 1999-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2147792
• 关键词: adipose tissue; bioenergetics; body composition; catecholamines; dietary lipid; esterification; exercise; fatty acid metabolism; free fatty acids; gas chromatography mass spectrometry; gender difference; glucagon; glucose metabolism; glycerol; hormone regulation /control mechanism; human subject; insulin; lipolysis; muscle metabolism; obesity; palmitates; propranolol; radioimmunoassay; somatostatin; somatotropin

Free fatty acids (FFA) mobilized from adipose tissue stores represent a major fuel source during prolonged exercise in humans. The aims of the studies in this proposal are 1) to evaluate the relative contributions of adipose tissue lipolysis and FFA reesterification to FFA availability during exercise, 2) to examine the nutritional and hormonal factors which regulate FFA mobilization in exercising men and women of average physical fitness, and 3) to assess the mechanisms by which changes in FFA availability affect glucose homeostasis during exercise in humans. Specifically, these studies will address 1) the potential gender differences in fat mobilization during equivalent exercise, 2) the influence of changes in dietary fat on FFA availability, 3) the effects of obesity and body fat distribution on fat mobilization during exercise, and 4) the relative roles of insulin, glucagon, and catecholamines in the regulation of FFA availability in exercising men and women. All subjects will be studied under basal postabsorptive conditions, during 2h of submaximal exercise on a cycle ergometer, and 90 min of post-exercise recovery. Isotopic tracer methods ([2H5] glycerol, [1-14C] palmitate, [3- 3H] glucose) will be utilized to trace lipolysis, FFA turnover, and glucose kinetics. Rates of FFA and glucose oxidation will be assessed by indirect calorimetry. Rates of FFA reesterification will be calculated from the rates of lipolysis, FFA turnover, and FFA oxidation. The pancreatic/pituitary clamp and glucose clamp techniques will be utilized in these studies to examine the isolated effects of the exercise-induced changes in insulin, glucagon, and catecholamines on FFA mobilization and glucose metabolism during exercise. These studies will be the first to address the potential gender differences in the in vivo lipolytic response to exercise and the nutritional and hormonal regulation of lipolysis and FFA reesterification during exercise in humans. A better understanding of the factors that influence fat mobilization during exercise will be relevant to the clinical application of exercise in the treatment of obesity, diabetes mellitus, and insulin-resistant states.

从脂肪组织店动员的游离脂肪酸（FFA）代表 长期运动期间的主要燃料来源。目的 该提案中的研究是1）评估 脂肪组织脂解和FFA重新酯化至FFA的可用性 在锻炼过程中，2）检查营养和荷尔蒙因素 调节FFA动员在运动平均身体的男人和女人中 健身和3）评估FFA变化的机制 可用性会影响人类运动过程中的葡萄糖稳态。 具体而言，这些研究将解决1）潜在性别 同等运动期间脂肪动员的差异，2） 饮食脂肪变化对FFA可用性的影响，3） 肥胖和体内脂肪分布在运动过程中动员脂肪动员，并且 4）胰岛素，胰高血糖素和儿茶酚胺在 在行使男性和女人方面的FFA可用性调节。所有主题 将在基础释放状态下进行研究，在2小时内 在周期测量计上次最大锻炼，运动后90分钟 恢复。同位素示踪剂方法（[2H5]甘油，[1-14C]棕榈酸酯，[3- 3H]葡萄糖将用于追踪脂肪解，FFA周转和 葡萄糖动力学。 FFA和葡萄糖氧化的速率将通过 间接量热法。将计算FFA重新酯化率 从脂解，FFA周转率和FFA氧化的速率中。这 将使用胰腺/垂体夹和葡萄糖夹技术 在这些研究中，以检查运动引起的孤立作用 FFA动员和胰岛素，胰高血糖素和儿茶酚胺的变化 运动过程中的葡萄糖代谢。这些研究将是第一个 解决体内脂肪解反应的潜在性别差异 运动以及脂解的营养和荷尔蒙调节 FFA在人类运动期间重新化。更好地理解 影响运动过程中脂肪动员的因素将是 与运动在治疗中的临床应用有关 肥胖，糖尿病和胰岛素耐药性状态。