Heart Disease Risk Factors In African Americans

非裔美国人的心脏病危险因素

• 批准号: 6983896
• 负责人: Anne E Sumner
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6983896
• 关键词: African American; body composition; cardiovascular disorder risk; clinical research; computed axial tomography; diabetes mellitus; fatty acid metabolism; free fatty acids; gender difference; glucose tolerance; glucose tolerance test; hormone regulation /control mechanism; human subject; insulin sensitivity /resistance; mathematical model; obesity; photon absorptiometry

Obesity, diabetes and heart disease are characterized by resistance to insulin as a glucoregulatory hormone. African Americans, particularly African American women suffer disproportionately from these three conditions. We believe that sex differences in sensitivity to insulin?s ability to suppress lipolysis contribute to the accelerated development of obesity, diabetes and heart disease in African American women. The hypothesis of this research is that African American men are resistant to insulin as a glucoregulatory hormone and resistant to insulin as a fat regulatory hormone. In contrast, African American women are resistant to insulin as a glucoregulatory hormone but sensitive to insulin as a fat regulatory hormone. The frequently sampled intravenous glucose tolerance test is used to measure insulin?s action as a glucoregulatory hormone. Unfortunately there is no index of insulin?s action as a fat regulatory hormone. Hence we are working on the development of this index by obtaining free fatty acids during the frequently sampled glucose tolerance test. Our goal is be able to do one test to obtain information about both actions of insulin. However, the development of an index of free fatty acid sensitivity to insulin during the frequently sampled intravenous glucose tolerance test involves sophisticated mathematical modeling and will need to be validated. As we work towards developing this index, we have studied sex differences in body fat content and distribution in African Americans. The distribution of body fat has a major impact on the interaction between insulin and body fat. We determined using serial slice computerized tomographic scans and dual X-ray absorptiometry (DXA) that there are sex differences in central body fat distribution in African Americans. These findings were published in the American Journal of Clinical Nutrition in November 2002. In addition, we have found that beta cell secretion of insulin is impaired in obese glucose intolerant African American women and this work was published in Diabetes Care in 2001. Now we are concentrating on sex differences in the free fatty acid profile during the frequently sampled intravenous glucose tolerance test. It is the intent that this free fatty acid work through the complicated process of modeling will lead to the development of an index of free fatty acid sensitivity to insulin. The development of this index is required so the research hypotheses can be fully tested. Further we are investigating the ability of insulin and lipid related variables to predict heart disease risk in African Americans.

肥胖，糖尿病和心脏病的特征是胰岛素耐药性作为葡萄糖调节激素。在这三个条件下，非洲裔美国人，特别是非裔美国妇女遭受不成比例的痛苦。我们认为，对胰岛素抑制脂解的敏感性的性别差异有助于非裔美国妇女肥胖，糖尿病和心脏病的加速发展。这项研究的假设是，非洲裔美国男性对胰岛素具有抗糖调节激素的抵抗力，并且抗胰岛素作为脂肪调节激素具有抵抗力。相比之下，非洲裔美国妇女对胰岛素具有抗糖调节激素的抵抗力，但对胰岛素作为脂肪调节激素敏感。经常采样的静脉葡萄糖耐量测试用于测量胰岛素的作用，作为葡萄糖调节激素。不幸的是，没有胰岛素作用指数作为脂肪调节激素。因此，我们正在通过在经常采样的葡萄糖耐受性测试中获得游离脂肪酸来开发该指数。我们的目标是能够进行一项测试，以获取有关两种胰岛素作用的信息。然而，在经常采样的静脉葡萄糖耐受性测试期间，游离脂肪酸敏感性的指数的发展涉及复杂的数学建模，需要进行验证。当我们努力开发该指数时，我们研究了非洲裔美国人体内脂肪含量和分布的性别差异。人体脂肪的分布对胰岛素和体内脂肪之间的相互作用有重大影响。我们使用串行切片计算机断层扫描和双X射线吸收法（DXA）确定，非裔美国人中央体内脂肪分布存在性别差异。这些发现发表在2002年11月的《美国临床营养杂志》上。此外，我们发现胰岛素的β细胞分泌在肥胖的葡萄糖不耐受的非洲裔美国妇女中受到损害，这项工作于2001年发表在糖尿病护理中。现在，我们专注于自由脂肪酸在经常进行散布的散布性测试中的性别差异。目的是，这种游离脂肪酸通过复杂的建模过程起作用，将导致发展自由脂肪酸对胰岛素敏感性的指数。需要该指数的开发，以便可以对研究假设进行全面检验。此外，我们正在研究胰岛素和脂质相关变量预测非裔美国人心脏病风险的能力。