The Platelet Metabolome in Obesity

描述(由申请人提供)：这项有指导的研究科学家发展计划的主要目标是在代谢组学和血栓形成研究领域创造一个密集的研究培训环境，在不久的将来导致独立的研究。该项目将在代谢失调和血栓形成方面具有专业知识的知名导师与一位在健康和疾病中的血小板分子表型方面具有经验的新兴年轻研究人员联合起来。该申请得到了对候选人的坚定机构承诺、稳健的培训环境和指导计划以及支持每个具体目标的初步数据的支持。因此，该提案是对努力增加代谢组学研究网络和能力的指导学员倡议的回应。该提案的中心研究假设是，肥胖通过涉及丝裂原蛋白-2(MFN-2)的机制诱导血小板代谢组和转录组的协调变化。这些变化导致了血小板的高反应性，从而增加了肥胖背景下血栓形成的风险。这项研究假设将通过三个特定的目标进行测试，这三个目标在主题上相关，但不依赖于彼此完成。特定的 目的1确定丝裂原蛋白-2在血小板代谢组-转录组网络中的作用及相关的功能活性。通过特异性地敲除血小板中的MFN-2，这些研究将揭示MFN-2在控制线粒体融合/分裂、代谢应激以及血小板的体外和体内功能方面的作用。他们还将确定最惠国待遇是否会改变基本的 代谢组和转录组或激活的代谢组足迹。特殊目标2将建立在第一个目标的基础上，但仍将独立测试血小板MFN-2在肥胖小鼠模型中的作用。假设MFN-2缺陷的血小板对高脂环境更敏感(即不能代偿)。因此，MFN-2缺陷的血小板将表现出过度的代谢应激和功能反应，这与无法在代谢物和转录物水平上进行补偿是一致的。第三个具体目标是将在老鼠身上获得的功能和机制数据扩展到人类。具体地说，这些研究将确定肥胖者和正常体重受试者分离的血小板中MFN-2的表达(即mRNA和蛋白质)和相关的线粒体活动是否不同。AIM 3还将确定肥胖是否会导致预测血小板高反应性的血小板代谢组和转录组的协调变化。对人类受试者的研究将产生新的临床相关信息，这些信息可能解释为什么肥胖者的血小板容易发生血栓。总之，这些临床前和临床研究将在促进研究事业发展的环境中探索新陈代谢和血栓研究的新范式。

DESCRIPTION (provided by applicant): The primary goal of this Mentored Research Scientist Development Proposal is to create an intensive research training environment in the field of metabolomics and thrombosis research that will lead to independent investigation in the near future. This project unites established mentors that have expertise in metabolic dysregulation and thrombosis with an emerging young investigator who has experience in the molecular phenotyping of platelets in health and disease. The application is supported by strong institutional commitment to the candidate, a robust training environment and mentoring plan, and preliminary data that supports each of the specific aims. Thus, the proposal is responsive to the mentored trainee initiative that strives to increase the network and capacity of metabolomics research. The central research hypothesis of the proposal is that obesity induces coordinate changes in the platelet metabolome and transcriptome through mechanisms that involve mitofusin-2 (Mfn-2). These changes lead to platelet hyperreactivity and, as a result, increased risk for thrombosis in the setting of obesity. This research hypothesis will be tested with 3 specific aims that are thematically related but do not rely on one another for completion. Specific aim 1 will determine the role of mitofusin-2 on the platelet metabolome-transcriptome network and related functional activities. By specifically knocking down Mfn-2 in platelets, these studies will reveal the roles for Mfn-2 in controlling mitochondrial fusion/fission, metabolic stress, and the in vitro and in vivo function of platelets. They will also determine if Mfn- 2 alters the basal metabolome and transcriptome or the activated metabolome footprint of platelets. Specific aim 2 will build on the first aim but nonetheless independently test the role of platelet Mfn-2 in a mouse model of obesity. It is hypothesized that Mfn-2 deficient platelets will be more susceptible (i.e., fail to compensate) to a high fat environment. As a result, Mfn-2 deficient platelet will display exaggerated metabolic stress and functional responses that are consistent with an inability to compensate at the metabolite and transcript level. The third specific aim will extend the functional and mechanistic data obtained in mice to humans. Specifically, the studies will determine if Mfn-2 expression (i.e., mRNA and protein) and related mitochondrial activities differs in platelets isolated from obese and normal weight human subjects. Aim 3 will also determine if obesity induces coordinate changes in the platelet metabolome and transcriptome that predict platelet hyperreactivity. Studies in human subjects will result in new, clinically relevant information that may explain why platelets are prone to thrombose in obese individuals. Together, these preclinical and clinical studies will explore new paradigms in metabolism and thrombosis research in an environment that enhances research career development.