VITAMIN C SUPPLEMENTATION AND VASCULAR ENDOTHELIAL FUNCTION IN OBESE/INSULIN

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。患心脏病和中风的风险随着糖尿病而急剧增加。先前的研究表明，与2型糖尿病相关的心脏病和中风的大部分风险是在糖尿病发作之前产生的。中年和老年超重的成年人患2型糖尿病和心脏病的风险增加。我们现在知道，排列在血管中的细胞通过释放帮助血管扩张（增加尺寸以携带更多血液）和分解血栓的物质，在预防心脏病方面发挥着重要作用。在肥胖和糖尿病患者中，这些细胞不能正常工作，导致扩张和分解血凝块的能力受损，增加了心脏病和中风的风险。最近的证据表明，补充维生素C可能有助于改善血管健康。这项研究的目的是确定维生素C补充剂是否可以提高血管扩张和释放一种物质的能力，这种物质有助于打破中年和老年超重个体的血栓，这些人患2型糖尿病和心血管疾病的风险增加。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The risks for heart attach and stroke increases dramatically with diabetes. Prior research indicates that much of the risk for heart disease and stroke associated with type 2 diabetes is generated prior to the onset of diabetes. Middle-aged and older overweight adults are at an increased risk of developing type 2 diabetes and heart disease. We now know that cells that line our blood vessels play an important role in preventing heart disease by releasing substances that help the vessel dilate (increase in size to carry more blood) and break down blood clots. In obese and diabetic individuals these cells do not function properly resulting in an impaired ability to dilate and break down blood clots increasing the risk of heart attach and stroke. Recent evidence suggests that vitamin C supplementation may be beneficial in improving the health of blood vessels. The purpose of this study is to determine whether vitamin C supplementation can improve the ability of blood vessels to dilate and release a substance that helps to break down blood clots in middle-aged and older overweight individuals at increased risk for type 2 diabetes and cardiovascular disease.