Proteomic determinants of direct measures of insulin sensitivity

胰岛素抵抗(IR)的后果不仅包括2型糖尿病，还包括一系列 代谢异常使发生危及生命的动脉粥样硬化并发症的风险增加一倍 包括心肌梗塞、缺血性中风和外周动脉疾病。流行率IR为 随着西方人口变得更重、更久坐不动，这一数字正以惊人的速度增长。当再有一个人 考虑到除#年肥胖症流行外，发展中国家正在进行的流行病学转变 在发达国家，IR对全球公共卫生的影响无疑是深远的。很少有药理作用 存在改善胰岛素敏感性和降低IR和新近发生的并发症风险的选择 对IR替代指标的基因组研究已经产生了令人失望的新线索数量。此外， 迫切需要开发更准确的基于血液的IR诊断测试。长期的 本研究的目的是发现和验证新的胰岛素抵抗的蛋白质标志物。 接受过两种直接测量胰岛素“黄金标准”之一的人的血液 敏感性：胰岛素抑制试验(IST)或正常血糖钳夹(EC)。这些信息将被用于 识别新的IR分子通路，这些通路可以作为药物靶点，并发展统计学 与直接测量胰岛素敏感性估计的IR程度高度相关的模型。在AIM 在这项提议中，2100名在斯坦福大学接受IST或 胰岛素敏感性与心血管疾病(RISC)关系的EC及Uppsala 成人男性纵向研究(ULSAM)研究将使用一种 利用称为邻近度扩展分析的新技术的新兴平台。这 这项技术可以准确、可靠地定量血浆中的蛋白质，甚至可以精确到股骨头或 大气压水平。我们将进一步验证在这些受试者中识别的顶部信号在另外的~300个非- 欧洲受试者和来自斯坦福大学的300名受试者的子集，他们在减肥后接受了第二次IST 或使用噻唑烷二酮。在目标2中，我们将使用 孟德尔随机化的原理，我们将量化经过验证的标记所提供的改进 识别IR并发症风险受试者的常规方法。在目标3中，确认关联 在自然界中看似有因果关系的蛋白质之间，将通过敲除基因来进一步检查 在人类细胞系中产生这些与IR相关的蛋白质。这些细胞系将包括脂肪细胞， 肝细胞和骨骼肌细胞。这项研究是关于血浆蛋白质组与直接相关的最大研究。 最早提出的胰岛素敏感性测量方法。这些发现有望产生重要的机械论见解。 探讨了红外光谱的分子基础，为血液诊断试验的发展奠定了基础 这可以非常可靠地检测出IR并发症的低风险或高风险的受试者。

The consequences of insulin resistance (IR) include not only type 2 diabetes mellitus but also a cluster of metabolic abnormalities that double the risk of developing life-threatening complications of atherosclerosis including myocardial infarction, ischemic strokes, and peripheral arterial disease. The prevalence IR is increasing at an alarming rate as western populations become heavier and more sedentary. When one further considers the ongoing epidemiological transitions in developing countries in addition to the obesity epidemic in developed countries, the worldwide public health impact of IR is undoubtedly profound. Few pharmacological options exist that improve one’s insulin sensitivity and decrease the risk of complications from IR and recent genomic studies of surrogate measures of IR have yielded a disappointing number of new leads. Furthermore, a critical need exists for the development of more accurate blood-based diagnostic tests for IR. The long-term objective of the proposed research is to discover and validate novel protein markers of IR circulating in the blood of individuals who have undergone either one of the two ‘gold standard’ direct measures of insulin sensitivity: an insulin suppression test (IST) or a euglycemic clamp (EC). This information will be used to identify novel molecular pathways of IR that can be targeted pharmacologically and to develop statistical models that correlate highly with the degree of IR as estimated by direct measures of insulin sensitivity. In aim 1 of this proposal, the blood of 2100 white/European subjects who have undergone an IST at Stanford or an EC in the Relationship between Insulin Sensitivity and Cardiovascular Disease (RISC) and the Uppsala Longitudinal Study of Adult Men (ULSAM) studies will be measured for the presence of 981 proteins using an emerging platform that leverages novel technology referred to as the proximity extension assay. This technology allows for the accurate and reliable quantification of proteins in plasma down to the femtomolar or attomolar level. We will further validate the top signals identified in these subjects in an additional ~300 non- European subjects and a subset of 300 subjects from Stanford who underwent a second IST after weight loss or use of a thiazolidinedione. In aim 2, we will examine validated signals from Aim 1 for causality using the principal of Mendelian randomization, and we will quantify improvements afforded by validated markers over conventional measures in identifying subjects at risk of complications from IR. In aim 3, validated associations between proteins that appear causal in nature will be further examined through knockdown of the genes producing these proteins in human cell lines relevant to IR. These cell lines will include adipocytes, hepatocytes, and skeletal myocytes. This study is the largest study of the plasma proteome in relation to direct measures of insulin sensitivity ever proposed. Findings are expected to yield important mechanistic insights into the molecular basis of IR and provide the foundation for the development of a blood-based diagnostic test that can very reliably detect subjects at low or high risk of complications from IR.