Genetic modification of heart performance

心脏功能的基因改造

• 批准号: 7751173
• 负责人: JOSEPH Mark METZGER
• 金额: $ 11.13万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2011-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7751173
• 关键词: Accounting; Adult; Affinity; Binding; Binding Proteins; Buffers; Calcium-Binding Proteins; Cardiac; Cardiac Myocytes; Country; Diastolic heart failure; Ectopic Expression; Engineering; Etiology; Failure; Family; Functional disorder; Gene Transfer; Genetic; Goals; Hand; Health; Heart; Heart failure; Human; In Vitro; Mammals; Medical; Modification; Muscle Cells; Muscle Fibers; Myocardium; Parvalbumins; Patients; Performance; Population; Positioning Attribute; Protein Isoforms; Proteins; Public Health; Range; Rate; Recombinant adeno-associated virus (rAAV); Recombinants; Relative (related person); Relaxation; Research; Research Personnel; Rodent; Sarcoplasmic Reticulum; Technology; Testing; Time; Variant; aged; combinatorial; improved; in vivo; mutant; novel; programs; research study; sorcin; vector

DESCRIPTION (provided by applicant): The long-range goal of this proposal is to identify, develop, and implement new experimental strategies that target improvement in diastolic performance in the failing myocardium. Health relevance derives from our focus on diastolic heart failure, which is a significant and growing medical problem in this country. There are few clinically effective treatments for diastolic heart failure, underscoring the relevance of this research to public health. We recently identified the Ca2+ binding protein parvalbumin (Parv) as a unique candidate to correct diastolic dysfunction in failing hearts. We showed that a key feature of Parv resides in the rather delicate trade-off between improvements in relaxation performance and diminution in contractility. This proposal will investigate two new strategies to correct diastolic dysfunction while retaining systolic performance. Two proteins demonstrated recently to improve Ca2+ release from the sarcoplasmic reticulum (SR) and enhance systolic function, but not diastolic function, are S100A1 and Sorcin. In complementary experiments, we will implement and test Parv isoforms and mutant Parvs that have biochemically determined variations in Mg2+ /Ca2+ binding affinities, to assess whether these novel Ca2+ buffers could correct diastolic dysfunction and preserve systolic performance. The Specific Aims are: Aim 1. To determine if dual gene transfer of Parv with either S100A1 or Sorcin will hasten relaxation performance and enhance contractility in adult cardiac myocytes in vitro. Hypothesis: Co-gene transfer of Parv with S100A1 or Sorcin will accelerate relaxation rate while maintaining or enhancing contractility in normal and failing myocytes. Aim 2. To test the contractile effects of Parv isoforms and mutants that have naturally occurring or engineered modifications in E-F hand Ca2+/Mg2+ binding affinities in myocytes in vitro. Hypothesis: Compared to wild-type alpha-Parv, Parv isoforms/mutants with biochemically determined increases in Mg2+ binding affinity will hasten relaxation performance without compromising contractility, even at high [ Parv] (0.5 mM). Aim 3. To use recombinant adeno-associated vectors (AAV6) for efficient (near 100% cardiac myocytes) and stable (months) expression of wild-type and modified Parvs in vivo. Hypothesis: Parvs with heightened Mg2+ affinities relative to wild-type Parv will enhance long-term diastolic performance and preserve systolic performance in the failing heart in vivo.

描述（由申请人提供）：本提案的长期目标是识别、开发和实施新的实验策略，以改善衰竭心肌的舒张性能为目标。健康相关性源于我们对舒张性心力衰竭的关注，舒张性心力衰竭是美国一个重要且日益严重的医疗问题。舒张性心力衰竭的临床有效治疗方法很少，强调了这项研究与公共卫生的相关性。我们最近确定了钙离子结合蛋白parvalbumin（Parv）作为一个独特的候选人，以纠正心脏舒张功能障碍。我们发现Parv的一个关键特征在于放松性能的改善和收缩性的降低之间的相当微妙的权衡。本提案将研究两种新的策略，以纠正舒张功能障碍，同时保持收缩性能。S100 A1和Sorcin是最近发现的两种能改善肌浆网Ca 2+释放并增强收缩功能而非舒张功能的蛋白质。在补充实验中，我们将实施和测试Parv同种型和突变Parv，其在Mg 2 + /Ca 2+结合亲和力方面具有生化测定的变化，以评估这些新型Ca 2+缓冲剂是否可以纠正舒张功能障碍并保持收缩性能。具体目标是：目标1。研究Parv与S100 A1或Sorcin双基因转染是否能促进离体成年心肌细胞的舒张性能和增强收缩性能。假设：Parv与S100 A1或Sorcin的共基因转移将加速舒张速率，同时维持或增强正常和衰竭心肌细胞的收缩性。目标2.检测Parv亚型和突变体在体外肌细胞中对E-F和Ca 2 +/Mg 2+结合亲和力的天然存在或工程修饰的收缩作用。假设：与野生型α-Parv相比，具有生物化学确定的Mg 2+结合亲和力增加的Parv同种型/突变体将加速松弛性能而不损害收缩性，即使在高[ Parv]（0.5 mM）下。目标3.使用重组腺相关载体（AAV 6）在体内有效（接近100%心肌细胞）和稳定（数月）表达野生型和修饰型Parvs。假设：相对于野生型Parv具有升高的Mg 2+亲和力的Parv将增强体内衰竭心脏的长期舒张性能并保持收缩性能。