miR-152: A Novel Regulator of Diabetic Cardiomyopathy

描述(由申请人提供)：本提案描述了一项为期五年的职业发展计划，为候选人Ioannis Karakikes博士成为一名独立调查员做好准备。该项目将以Karakikes博士作为基础细胞和分子生物学家的背景为基础，提供分子心脏病学和多模式心脏成像方法方面的专业知识。导师是罗杰·哈贾尔博士，他是西奈山医学院的医学教授和心血管研究中心主任。拟议的导师是心脏生理学和心脏基因治疗方面的专家。K99阶段将包括主要导师的有组织的指导、与咨询委员会的补充会议、正式的课程作业、具有挑衅性的研究项目和职业过渡计划。在他的初步研究中，Karakikes博士开发并验证了一套分子和细胞生物学工具来研究microRNAs(MiRNAs)在糖尿病心肌病发病机制中的潜在作用。Karakikes博士已经确定了几个与糖尿病心肌病相关的miRNAs，然而，拟议的研究将集中在miRNA-152(miR-152)的详细特征上。在初步研究中，Karakikes博士已经证明，miR-152的过度表达深刻地改变了体外培养的原代心肌细胞的葡萄糖摄取，并诱导了肥大反应和收缩功能障碍。在研究方法上，卡拉基克斯博士将在这些发现的基础上，验证miR-152在体内调节心脏收缩能力和心室重塑的假设。到目前为止，候选人已经积累了对miRNA调节的心功能进行拟议的全面分析所需的技术能力。为了解决该项目的总体目标，建立了一个可诱导的心脏特异性miR-152转基因小鼠模型。这一模型将被用来表征miRNA在心脏功能、心室重构中的作用，并确定其靶基因。在K99阶段的特定目标1和2中，候选人将使用多参数成像、血流动力学和电生理学方法评估miR-152过度表达小鼠的心功能。这些研究将与心脏组织样本的详细组织学和分子分析相结合。在R00片段的特定目标3和4期间，候选人将使用一套全面的分子方法来确定miR-152的特定目标基因和可能的调控网络，这些网络介导糖尿病心脏的病理重构。卡拉基克斯博士的最终目标是利用这些信息开发治疗糖尿病相关心脏功能障碍的新疗法。总之，这项拟议的工作将阐明新的基于mi-RNA的心血管功能和病理生理学机制。此外，这项工作将为卡拉基克斯博士作为独立研究员最终开展的关于miR-152和其他miRNAs在心脏功能中的作用的未来研究提供基础。

DESCRIPTION (provided by applicant): This proposal describes a five-year career development program to prepare the Candidate, Dr. Ioannis Karakikes, for a career as an independent investigator. This program will build on Dr. Karakikes' background as a basic cell and molecular biologist by providing expertise in molecular cardiology and multimodality cardiac imaging methodologies. The mentor is Dr. Roger Hajjar who is Professor of Medicine and Director of the Cardiovascular Research Center at the Mount Sinai School of Medicine. The proposed mentor is an expert in cardiac physiology and cardiac gene therapy. The K99 phase will consist of structured mentorship by the primary mentor, complementary meetings with an advisory committee, formal coursework, a provocative research project and a program of career transition. In his preliminary studies, Dr. Karakikes has developed and validated a set of molecular and cell biology tools to study the potential role of microRNAs (miRNAs) in the pathogenesis of diabetic cardiomyopathy. Dr. Karakikes has identified several diabetic cardiomyopathy- associated miRNAs, however, the proposed studies will focus on the detailed characterization of miRNA-152 (miR-152). In preliminary studies, Dr. Karakikes has demonstrated that miR-152 overexpression profoundly altered glucose uptake and induced a hypertrophic response and contractile dysfunction in primary cardiomyocytes in vitro. In the research approach, Dr. Karakikes will build on these findings to test the hypothesis that miR-152 regulates cardiac contractility and ventricular remodeling in vivo. To date the Candidate has accrued the technical competencies necessary to conduct the proposed comprehensive analysis of miRNA modulated cardiac function. To address the overall goal of the project, an inducible cardiac- specific miR-152 transgenic mouse model was generated. This model will be used to phenotypically characterize the role of miRNA in cardiac function, ventricular remodeling and to determine its target genes. In Specific Aims 1 and 2 of the K99 phase, the Candidate will assess cardiac function in miR-152 overexpressing mice using multiparametric imaging, hemodynamic and electrophysiological methodologies. These studies will be coupled with detailed histological and molecular analysis of cardiac tissue samples. During Specific Aims 3 and 4 of the R00 segment, the Candidate will use a comprehensive set of molecular approaches to identify the specific target genes for miR-152 and possible regulatory networks that mediate pathological remodeling in the diabetic heart. Dr Karakikes' ultimate goal is to use this information to develop novel therapeutic modalities for diabetes-related cardiac dysfunction. Collectively, the proposed work will elucidate novel mi-RNA-based mechanisms underlying cardiovascular function and pathophysiology. In addition, this work will provide a foundation for future studies on the role of miR-152 and other miRNAs in heart function to be eventually carried out by Dr. Karakikes as an independent investigator.