Functional role of IP3 receptors in the regulation of cardiac myofibroblasts

IP3受体在心肌成纤维细胞调节中的功能作用

• 批准号: 10650161
• 负责人: Gaetano Santulli
• 金额: $ 41.75万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10650161
• 关键词: Ablation; Adult; Animal Model; Arrhythmia; Attenuated; Autophagocytosis; Autophagosome; Biology; Calcium; Calcium Channel; Cardiac; Cardiac Myocytes; Cardiovascular Diseases; Cells; Data; Development; Embryo; Endoplasmic Reticulum; Event; Extracellular Matrix; Fibroblasts; Fibrosis; Functional disorder; Genes; Genetic Recombination; Goals; Heart; Heart Diseases; Heart failure; Human; Hypertrophy; ITPR1 gene; In Vitro; Inflammation; Inflammatory; Inflammatory Response; Inositol; Investigation; Ischemia; Knockout Mice; Link; Mammals; Measures; Mediating; Mission; Mitochondria; Modeling; Molecular; Mus; Myocardial Infarction; Myocardial Ischemia; Myocardial dysfunction; Myofibroblast; Pathogenicity; Pathway interactions; Phenotype; Play; Protein Isoforms; Public Health; Regulation; Reperfusion Therapy; Role; Signal Transduction Pathway; Site; Stimulus; Techniques; Testing; Therapeutic; Time; United States; United States National Institutes of Health; Up-Regulation; coronary fibrosis; endoplasmic reticulum stress; experimental study; genome wide association study; healing; heart function; human disease; in vivo; innovation; inorganic phosphate; ischemic injury; knock-down; loss of function; mitochondrial dysfunction; mortality; mouse model; novel; pharmacologic; receptor; release of sequestered calcium ion into cytoplasm; response; tool

Cardiovascular disorders remain the first cause of mortality in US, with myocardial infarction (MI) and subsequent heart failure as the major sequela underlying such lethality. Recent studies have reinforced the concept that cardiac fibroblasts (FBs), which are less investigated than cardiomyocytes, are much more than simple regulators of extracellular matrix turnover; indeed, these cells (and their activated phenotype, myoFBs) seem to be key players in heart failure progression. Although relatively understudied, myocardial fibrosis remains one of the major pathophysiologic features of ischemic cardiac disorders. Inositol 1,4,5-trisphosphate receptors (IP3Rs) are intracellular calcium release channels located on the endoplasmic reticulum (ER), the main calcium reservoir within the cell. While the role of IP3Rs in cardiomyocytes has been previously investigated, especially in the context of hypertrophy and arrhythmias, their exact function in the activation of cardiac FBs following an ischemic insult has not been explored hitherto. Human and murine FBs express all three isoforms of IP3Rs and their activity and levels are modulated by several stimuli. We hypothesize that IP3Rs play a key role in the activation of cardiac FBs in the infarcted heart and in the present proposal we will test this hypothesis in vivo, ex vivo, and in vitro. We have preliminary data showing that IP3R expression (all isoforms) is increased in cardiac FBs following MI. Moreover, genome-wide association studies revealed a significant association between IP3- mediated signal transduction pathways and ischemic heart disease. However, definitive functional studies examining the mechanistic role of IP3Rs in cardiac fibrosis in vivo are missing. Using a Cre/lox recombination technique, we generated a novel mouse model (IP3RKO) in which IP3Rs are ablated in activated cardiac myoFBs. This model provides an exquisite tool to evaluate the functional contribution of IP3R to cardiac fibrosis and allows us to overcome the difficulties encountered following the knockdown or KO of a single IP3R gene. Our preliminary studies show that following MI, IP3RKO mice display a significantly reduced fibrosis and attenuated myocardial dysfunction compared with control IP3RCre and IP3Rflox littermates. We will further assess the functional relationships between IP3Rs and cardiac fibrosis in primary isolated cardiac FBs at different time points and in response to established stimuli, in order to assess their proliferative, migratory, secretory, and contractile capacity. Additionally, we will examine IP3R-mediated responses in murine embryonic FBs and human cardiac FBs. To delineate the molecular mechanisms underlying the observed phenotype, we propose to explore the following calcium-mediated pathways: mitochondrial dysfunction, autophagy, ER stress, and inflammation. The proposed studies are highly significant and innovative as they will: (a) provide the first assessment of the functional role of IP3R in post-MI cardiac FBs using a specific Cre/lox KO model; (b) delineate previously unrecognized connections between IP3R and autophagy in the pathophysiology of cardiac fibrosis; (c) identify innovative therapeutic strategies that specifically target excessive post-ischemic cardiac fibrosis.

心血管疾病仍然是美国死亡的首要原因，其中包括心肌梗死（MI）和随后的 心力衰竭是这种致命性的主要后遗症。最近的研究加强了这样一个概念， 心脏成纤维细胞（FB）比心肌细胞研究得少， 调节细胞外基质周转;事实上，这些细胞（及其活化表型，myoFB）似乎 成为心力衰竭进展的关键因素。尽管相对而言研究不足，心肌纤维化仍然是 缺血性心脏病的主要病理生理特征。肌醇1，4，5-三磷酸受体（IP 3Rs） 是位于内质网（ER）上的细胞内钙释放通道，内质网是主要的钙储存库 在细胞内。虽然先前已经研究了IP 3R在心肌细胞中的作用，特别是在心肌细胞中。 在肥大和心律失常的背景下，它们在心脏FB激活中的确切功能， 迄今为止还没有研究过局部缺血损伤。人和鼠FB表达IP 3R的所有三种同种型 并且它们的活性和水平由几种刺激调节。我们假设，IP 3R发挥了关键作用， 在本发明中，我们将在体内测试这一假设， 体内和体外。我们有初步的数据表明，IP 3R表达（所有亚型）增加，在心脏 MI后的FB。此外，全基因组关联研究揭示了IP 3- 介导的信号转导通路与缺血性心脏病的关系。然而，明确的功能研究 研究IP 3R在体内心脏纤维化中的机制作用是缺失的。使用Cre/lox重组 技术，我们产生了一种新的小鼠模型（IP 3RKO），其中IP 3R在激活的心脏myoFB中被消融。 该模型提供了一个精致的工具来评估IP 3R对心脏纤维化的功能贡献，并允许 我们克服了单个IP 3 R基因敲除或KO后遇到的困难。我们的初步 研究表明，MI后，IP 3RKO小鼠显示出显著减少的纤维化和减弱的心肌纤维化。 与对照IP 3RCre和IP 3Rflox同窝仔相比，我们将进一步评估功能 在不同时间点的原发性分离心脏FB中IP 3Rs与心脏纤维化之间的关系， 对既定刺激的反应，以评估其增殖，迁移，分泌和收缩 容量此外，我们还将检测小鼠胚胎FB和人心脏中IP 3R介导的反应， FBI为了描述所观察到的表型的分子机制，我们建议探索 以下钙介导的途径：线粒体功能障碍，自噬，ER应激和炎症。的 拟议的研究非常重要和创新，因为它们将：（a）对 使用特异性Cre/lox KO模型，IP 3 R在MI后心脏FB中的功能作用;（B）描述先前 在心脏纤维化的病理生理学中IP 3R和自噬之间未被认识到的联系;（c）鉴定 创新的治疗策略，专门针对过度缺血后心脏纤维化。

项目成果

Therapeutic concordance improves blood pressure control in patients with resistant hypertension.

治疗一致性可改善难治性高血压患者的血压控制。

• DOI: 10.1016/j.phrs.2022.106557
• 发表时间: 2023-01
• 期刊: Pharmacological research
• 影响因子: 9.3
• 作者: Trimarco V;Izzo R;Mone P;Lembo M;Manzi MV;Pacella D;Falco A;Gallo P;Esposito G;Morisco C;Santulli G;Trimarco B
• 通讯作者: Trimarco B

Vitamin C and Cardiovascular Disease: An Update.

• DOI: 10.3390/antiox9121227
• 发表时间: 2020-12-03
• 期刊: Antioxidants (Basel, Switzerland)
• 作者: Morelli MB;Gambardella J;Castellanos V;Trimarco V;Santulli G
• 通讯作者: Santulli G