Heart Disease Risk Factors In African Americans

非裔美国人的心脏病危险因素

• 批准号: 6673625
• 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/6673625
• 关键词: African American; body composition; cardiovascular disorder risk; clinical research; fatty acid metabolism; free fatty acids; gender difference; glucose tolerance; glucose tolerance test; hormone regulation /control mechanism; human subject; insulin sensitivity /resistance; obesity

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 will be 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.

肥胖、糖尿病和心脏病的特点是对作为葡萄糖调节激素的胰岛素产生抵抗。非裔美国人，特别是非裔美国女性，尤其遭受这三种疾病的困扰。我们认为，对胰岛素抑制脂肪分解能力的敏感性的性别差异导致非裔美国女性肥胖、糖尿病和心脏病的加速发展。这项研究的假设是，非裔美国男性对胰岛素作为葡萄糖调节激素有抵抗力，对胰岛素作为脂肪调节激素有抵抗力。相比之下，非裔美国女性对胰岛素这种葡萄糖调节激素有抵抗力，但对胰岛素这种脂肪调节激素敏感。经常采样的静脉内葡萄糖耐量试验用于测量胰岛素作为葡萄糖调节激素的作用。不幸的是，没有胰岛素作为脂肪调节激素的作用指标。因此，我们正在通过在频繁采样的葡萄糖耐量测试中获取游离脂肪酸来开发该指数。我们的目标是能够通过一项测试来获取有关胰岛素两种作用的信息。然而，在频繁采样的静脉内葡萄糖耐量测试过程中，游离脂肪酸对胰岛素敏感性指数的制定涉及复杂的数学模型，需要进行验证。 在我们努力制定该指数的过程中，我们研究了非裔美国人体内脂肪含量和分布的性别差异。身体脂肪的分布对胰岛素和身体脂肪之间的相互作用有重大影响。我们使用连续切片计算机断层扫描和双 X 射线吸收测定法 (DXA) 确定非裔美国人的中央身体脂肪分布存在性别差异。这些研究结果将于 2002 年 11 月发表在《美国临床营养学杂志》上。此外，我们发现肥胖的葡萄糖不耐症非洲裔美国女性的 β 细胞分泌胰岛素受到损害，这项工作于 2001 年发表在《糖尿病护理》上。现在，我们将重点放在频繁采样的静脉内葡萄糖耐量试验中游离脂肪酸谱的性别差异。其目的是，这种游离脂肪酸通过复杂的建模过程起作用将导致游离脂肪酸对胰岛素敏感性指数的发展。需要制定该指数，以便充分检验研究假设。