Adenylyl Cyclase and Cardiac Interstitium

腺苷酸环化酶和心脏间质

• 批准号: 7217649
• 负责人: PAUL A INSEL
• 金额: $ 38.13万
• 依托单位: VETERANS MEDICAL RESEARCH FDN/SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7217649
• 关键词: adenylate cyclase; biological signal transduction; cardiovascular disorder; cell proliferation; cyclic AMP; disease /disorder model; fibroblasts; fibrosis; immunocytochemistry; isozymes; laboratory mouse; laboratory rat; phenotype; polymerase chain reaction; protein kinase A; protein localization; tissue /cell culture; transfection; western blottings

Cardiac fibrosis, a pathological consequence of cardiac injury, can be manifest either as localized scar or more diffuse interstitial fibrosis. The cells responsible for cardiac fibrosis are cardiac fibroblasts, which numerically are the most prevalent cells in the heart. Cardiac fibroblasts are regulated by hormones, many of which act via plasma membrane receptors, including ones that are linked to heterotrimeric G proteins and G-protein- regulated effectors. One such effector, adenylyl cyclase, catalyzes the formation of cyclic AMP from ATP and is the focus of this proposal. Cyclic AMP has anti-fibrotic actions that include inhibition of the transformation of "resting" cardiac fibroblasts to pro-fibrogenic myofibroblasts. This proposal will test several hypotheses related to the ability of increased cyclic AMP formation, produced by enhanced expression of adenylyl cyclase-6 (AC-6), to alter biochemical and functional activities of cardiac fibroblasts. Studies will be conducted using primary cultures of cardiac fibroblasts and, in addition, will involve the use of an animal model (angiotensin infusion in rats and mice) that produces cardiac fibrosis. The experiments focus on AC-6 with an emphasis on its compartmentation with proximal and distal signaling components as well as impact of increased AC-6 expression on the fibrotic response, as assessed by several phenotypic characteristics. The results should provide proof-of-principle data regarding the potential for therapeutic targeting of cardiac fibroblasts by gene transfer with AC-6 and potentially other AC isoforms. It is likely that targeting of AC-6 to cardiac myocytes via intracoronary delivery of recombinant viral vectors (Project 1) will increase AC-6 expression in fibroblasts. The general hypothesis of Project 2 is that increased expression of AC-6 in cardiac fibroblasts will alter the fibrotic response and favorably modify cardiac remodeling to improve cardiac function in the failing heart.

心脏纤维化是心脏损伤的病理结果，可以表现为局部瘢痕或局部炎症。 弥漫性间质纤维化。引起心脏纤维化的细胞是心脏成纤维细胞， 是心脏中最常见的细胞。心脏成纤维细胞受激素调节，许多 其通过质膜受体起作用，包括与异源三聚体G蛋白和G蛋白- 调节效应器。一种这样的效应物，腺苷酸环化酶，催化环AMP的形成， ATP是本提案的重点。环磷酸腺苷具有抗纤维化作用，包括抑制 将“静息”心脏成纤维细胞转化为促纤维化肌成纤维细胞。该提案将测试几个 与环磷酸腺苷形成增加的能力有关的假设， 腺苷酸环化酶-6（AC-6），以改变心脏成纤维细胞的生化和功能活性。研究将 使用心脏成纤维细胞的原代培养物进行，此外，将涉及使用动物 模型（大鼠和小鼠血管紧张素输注）产生心脏纤维化。实验的重点是AC-6 重点在于其与近端和远端信号成分的区室化以及影响 AC-6表达增加对纤维化反应的影响，如通过几种表型特征所评估的。 这些结果应该提供关于心脏靶向治疗潜力的原理验证数据。 通过用AC-6和潜在的其他AC同种型进行基因转移来制备成纤维细胞。很可能，以AC-6为目标， 通过冠状动脉内递送重组病毒载体（项目1）的心肌细胞将增加AC-6 在成纤维细胞中表达。项目2的一般假设是AC-6在心脏中的表达增加， 成纤维细胞将改变纤维化反应并有利地改变心脏重塑以改善心脏功能。 在衰竭的心脏中发挥作用。