The Role of C-Kit Positive Cardiac Progenitors in Maternal Diabetes-Induced Heart Defects and the Therapeutic Values of These Cells

项目摘要 先天性心脏病是最常见的出生缺陷。妊娠期糖尿病是 一种与冠心病和心脏功能障碍增加五倍相关的非遗传因素。潜在的 糖尿病引起的冠心病和心功能不全的机制尚不清楚，但有一种机制可能 包括通过高糖水平抑制心脏生成。C-Kit+心脏祖细胞(CPC)现在 正在研究作为成人心力衰竭患者刺激心功能的潜在治疗选择。 我们的初步研究已经确定，糖尿病和高血糖在体外都会诱导一系列 C-kit+CPC中的细胞功能障碍，这与糖尿病诱导的冠心病的病因有关。消除c- 在心脏发生过程中，KIT+CPC导致类似于糖尿病妊娠后代的CHDS。同样 重要的是要确定在母亲糖尿病暴露期间对 出生后衍生的c-Kit+CPC将用于我们即将进行的基于自体的c-Kit+CHD试验。 因此，我们假设糖尿病患者的高血糖导致c-kit+细胞功能障碍。 它导致心脏间隔缺陷，限制了心脏重构的作用。 Natal在受损心脏上衍生c-kit+CPC。减少细胞压力或DNA甲基化或 C-kit+CPC中组蛋白乙酰化可缓解母体糖尿病引起的冠心病，并改善 体外扩增的c-kit+CPC恢复旁分泌功能的治疗价值。研究 都是专为揭示糖尿病或高血糖对c-kit+CPC的作用而设计的。目标1将 确定细胞应激诱导的c-kit+CPC功能障碍是否与致畸有关 产妇糖尿病的症状。我们假设糖尿病触发细胞凋亡并减少c-kit+的细胞增殖 通过细胞应激，损害心脏间隔和临界心脏间隔的功能 调节因子：第二心域前体细胞和心脏神经脊细胞。目标2将决定是否 C-kit+CPC中组蛋白乙酰化和DNA甲基化增强介导的不良反应 母体糖尿病对心脏生成和这些祖细胞的印记。我们假设 糖尿病降低的sirtuin脱乙酰酶2(SIRT2)导致DNA高甲基化导致c-kit+CPC 严重涉及心脏间隔改变和不良印迹的细胞功能障碍。目标3将 检测子代c-kit+CPC及其外切体的治疗能力 非糖尿病和糖尿病母亲的心肌梗死模型和糖尿病患者胚胎心脏 怀孕了。我们假设母体糖尿病患者的后代c-kit+cpc的能力较低。 在修复由miR-34a上调引起的CHDS和心功能障碍方面，miR-34a上调改变了分泌组和 外切体谱与非糖尿病母亲相比，并保持高水平的细胞应激，组蛋白 CPC治疗中的乙酰化和DNA甲基化。

Project Summary Congenital heart defects (CHDs) are the most common birth defects. Pregestational maternal diabetes is a noninherited factor associated with a five-fold increase in CHDs and cardiac dysfunction. The underlying mechanism of diabetes-induced CHDs and cardiac dysfunction is unknown but one mechanism may involve inhibition of cardiogenesis by high glucose levels. c-Kit+ cardiac progenitor cells (CPCs) are now being studied as a potential treatment option for adult heart failure patients for stimulating cardiac function. Our preliminary studies have determined that both diabetes and high glucose in vitro induce a spectrum of cellular dysfunction in c-kit+ CPCs, that is implicated in the etiology of diabetes-induced CHDs. Eliminating c- kit+ CPCs during cardiogenesis led to CHDs resembling those in diabetic pregnancy offspring. Equally important is to determine the adverse programming effect caused during maternal diabetic exposure on the postnatal derived c-kit+ CPCs which will be used in our upcoming autologous based c-kit+ CHD trial. Therefore, we hypothesize that high glucose in diabetes induces cellular dysfunction in c-kit+ CPCs, which contributes to cardiac septation defects and limits the remodeling effect of post- natal derived c-kit+ CPCs on damaged hearts. Reducing cellular stress or DNA methylation or histone acetylation in c-kit+ CPCs alleviates maternal diabetes-induced CHDs, and improves the therapeutic value of ex vivo expanded c-kit+ CPCs by restoring their paracrine function. Studies are designed specifically to reveal the diabetes or high glucose on c-kit+ CPC function. Aim 1 will determine whether cellular stress-induced c-kit+ CPCs dysfunction contributes to the teratogenicity of maternal diabetes. We hypothesize that diabetes triggers apoptosis and reduce cell proliferation of c-kit+ CPCs through cellular stress, which impairs cardiac septation and the function of critical cardiac septation regulators: second heart field progenitors and cardiac neural crest cells. Aim 2 will determine whether enhanced histone acetylation and DNA methylation in c-kit+ CPCs mediate the adverse effects of maternal diabetes on cardiogenesis and imprinting on these progenitors. We hypothesize that diabetes-reduced sirtuin deacetylase 2 (SIRT2) causes DNA hypermethylation leading to c-kit+ CPCs cellular dysfunction that critically involve in altered cardiac septation and adverse imprinting. Aim 3 will determine the therapeutic abilities of offspring derived c-kit+ CPCs and their exosomes from nondiabetic and diabetic mothers in a myocardial infarction model and embryonic hearts of diabetic pregnancy. We hypothesize that offspring derived c-kit+ CPCs from maternal diabetics have lower abilities in repairing CHDs and cardiac dysfunction due to miR-34a up-regulation, which alters secretome and exosome profiling compared with nondiabetic mothers, and retain high levels of cellular stress, histone acetylation and DNA methylation during CPC therapies.