BIOENERGETIC REGULATION OF CARDIAC PROGENITOR CELLS

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 糖酵解和线粒体能量学的重组被认为是干细胞分化所必需的，支持表型特化需要遗传电路和发育生物能量学的协调的观点。这意味着代谢性疾病如糖尿病可能对心脏祖细胞（CPC）特别具有破坏性，从而限制了它们在患病心肌的环境中分化和耐受应激的能力。我们计划研究有丝分裂原在介导CPC分化所需的糖酵解和线粒体能量学变化中的作用。 一般的假设是，有丝分裂原信号与能量的发展线索被破坏，在糖尿病，从而防止分化为心肌细胞的CPC。 具体目标是： 1.检查有丝分裂原对CPC能量学的影响。 由于有丝分裂原，如胰岛素和IGF-1在CPC归巢和分化中发挥重要作用，我们将研究这些有丝分裂原的存在和缺失如何影响糖酵解通量和线粒体生物能量学。将检查胰岛素抵抗对能量学的影响，并通过共聚焦显微镜和流式细胞术监测心肌细胞分化。 2.确定糖酵解如何调节CPC的生长和分化。使用药理学和分子干预（例如，koningic acid和PFK-2敲低或过表达），我们将在模拟正常和糖尿病表型的底物条件下研究糖酵解在CPC生长和分化中的作用。 通过细胞外通量分析检查能量学，并通过GFP-Nkx 2.5的表达测量向心脏谱系的分化。 3.评估重新植入有活力的CPC是否会增加其治疗效果。 具有高糖酵解和/或线粒体能力的CPC将被重新植入梗死的心脏中。 将通过超声心动图评价心肌功能，并通过心脏组织切片中的共聚焦显微镜分析植入。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. A restructuring of glycolysis and mitochondrial energetics is thought to be required for stem cell differentiation, supporting the view that phenotype specification requires the coordination of genetic circuits and developmental bioenergetics. This implies that metabolic diseases such as diabetes may be particularly destructive to cardiac progenitor cells (CPCs), thereby limiting their ability to differentiate and tolerate stress in the milieu of the diseased myocardium. We plan to examine the role of mitogens in mediating the changes in glycolysis and mitochondrial energetics required for CPC differentiation. The general hypothesis is that the developmental cues that relate mitogen signaling with energetics are disrupted in diabetes, thereby preventing differentiation of CPCs into cardiomyocytes. The specific aims are to: 1. Examine the effects of mitogens on CPC energetics. Because mitogens such as insulin and IGF-1 play important roles in CPC homing and differentiation, we will examine how the absence and presence of these mitogens affect glycolytic flux and mitochondrial bioenergetics. The effect of insulin resistance on energetics will be examined, and cardiomyocyte differentiation will be monitored by confocal microscopy and flow cytometry. 2. Determine how glycolysis regulates CPC growth and differentiation. Using pharmacological and molecular interventions (e.g., koningic acid and PFK-2 knockdown or overexpression), we will examine the role of glycolysis in CPC growth and differentiation under substrate conditions that mimic the normal and diabetic phenotype. Energetics will be examined by extracellular flux analysis and differentiation into the cardiac lineage will be measured by expression of GFP-Nkx2.5. 3. Assess whether reimplantation of energetically competent CPCs increases their therapeutic efficacy. CPCs with high glycolytic and/or mitochondrial capacities will be reimplanted in the infarcted heart. Myocardial function will be evaluated by echocardiography and engraftment will be analyzed by confocal microscopy in heart tissue sections.