PKC Isozymes in Hypoxia-Induced Fibroblast Proliferation

缺氧诱导的成纤维细胞增殖中的 PKC 同工酶

• 批准号: 7330312
• 负责人: MITA DAS
• 金额: $ 34.91万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-05-01 至 2008-09-23
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7330312
• 关键词: 1-Phosphatidylinositol 3-Kinase; Acute; Address; Animals; Antisense Oligonucleotides; Anus; Appearance; Biochemical; Biochemical Pathway; Blood flow; Cell Nucleus; Cell Proliferation; Cells; Chemicals; Chronic; Condition; Control Animal; Cytoplasm; Development; Dominant-Negative Mutation; Exhibits; Extracellular Signal Regulated Kinases; Family; Family member; Fibroblasts; Fibrosis; Figs - dietary; Genes; Goals; Growth; Heart failure; Hypertension; Hypoxia; In Vitro; Isoenzymes; Lead; Lung; Lung diseases; Mediating; Mediator of activation protein; Mitogen Activated Protein Kinase 1; Mitogen-Activated Protein Kinases; Molecular; Neonatal; Nuclear; Nuclear Envelope; Nuclear Export; Nuclear Localization Signal; Nuclear Protein; Nuclear Proteins; Nuclear Translocation; Obstruction; Pathway interactions; Peptides; Phosphatidylinositols; Phosphoinositide-3-Kinase, Catalytic, Gamma Polypeptide; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphorylation Site; Phosphotransferases; Population; Property; Protein Dephosphorylation; Protein Kinase C; Pulmonary Hypertension; Pulmonary Vascular Resistance; Pulmonary artery structure; Regulation; Research Personnel; Rest; Role; Signal Pathway; Signal Transduction; Signaling Protein; Small Interfering RNA; Specificity; Stimulus; Therapeutic; Threonine; Translating; Tumor Suppressor Proteins; Tunica Adventitia; Vascular Diseases; cell type; citrate carrier; day; expectation; expression vector; extracellular; human MAPK14 protein; improved; inhibitor/antagonist; insight; member; novel; programs; promoter; research study; response

Chronic hypoxia induces dramatic fibro-proliferative remodeling in the pulmonary artery (PA)adventitia that is especially impressive during the neonatal period and clearly contributes to the marked increase in pulmonary vascular resistance observed. One of the key mediators of these responses is protein kinase C (PKC) ¿ (zeta) which regulates hypoxia-inducible genes. To study the adventitial remodeling, we used PA adventitial fibroblasts cultured from neonatal control (Fib-C) and hypoxic pulmonary hypertensive calves (Fib-H) and compared the effects of hypoxia on PKC¿-related signaling pathways. We have observed that acute hypoxic exposure induces translocation of nuclear PKC¿ into the nuclear membrane and the cytoplasm selectively in Fib-C, but not in Fib-H. In Fib-C, PKG; inhibition results in sustained activation of extracellular signal-regulated kinases, ERK1/2, whereas it blocks ERK1/2 activation in Fib-H. The mechanisms by which PKC¿ can diversify its own biochemical properties in response to chronic hypoxia remain unexplored. Although PKC¿ suppresses the hypoxia-induced proliferation of Fib-C, it translates the hypoxic signal into replicative responses in Fib-H. The molecular mechanisms that confer the ability of PKC¿ to perform opposing functions, especially in proliferative responses, are unknown and will be examined here. We also found that PKC^ regulates MAP kinase phosphatase-1 (MKP-1) expression only in Fib-C, but not in Fib-H. The biochemical pathways responsible for uncoupling of PKQ; from the regulation of MKP-1 expression in Fib-H are not known. The aforementioned questions will be addressed by the following specific aims: 1) The development of hypoxic pulmonary hypertension leads to the appearance of fibroblasts with modified nuclear localization, activation and target specificity of PKC¿; 2) An altered functional role of PKC¿ as a growth regulator, promotes enhanced proliferation of fibroblasts from chronically hypoxic animals; 3) Nuclear PKC^-mediated growth-suppressing activity of MKP-1 is absent in fibroblasts isolated from the adventitial compartment of chronically hypoxic animals. Successful completion of the proposed experiments will provide new insights into the role of PKCf; and MKP-1 in pulmonary vascular diseases and could lead to the development of improved therapeutic strategies for the treatment of pulmonary diseases caused by chronic hypoxia.

慢性缺氧会引起肺动脉（PA）膜的戏剧性纤维增生重塑 在新生儿期间特别令人印象深刻，显然有助于明显增加 观察到肺血管阻力。这些反应的关键介体之一是蛋白激酶C （Zeta）（Zeta）调节低氧诱导基因。为了研究冒险重塑，我们使用了PA 从新生儿对照（FIB-C）和低氧肺高血压小牛培养的外膜成纤维细胞 （FIB -H）并比较了缺氧对PKCC相关信号通路的影响。我们已经观察到 急性低氧暴露会诱导核PKC易位到核膜和 在FIB-C中有选择性的细胞质，但在FIB-H中不选择。在fib-c中，pkg;抑制作用导致持续激活 细胞外信号调节的激酶，ERK1/2，而它阻断了FIB-H中的ERK1/2激活。这 PKC响应慢性缺氧而使PKCS多样化的机制多样化 尽管PKC抑制了缺氧引起的Fib-C的增殖，但它翻译了 在FIB-H中的复制响应中低氧信号。会议的分子机制 执行相反的功能，尤其是在增殖的反应中，未知，将被检查 这里。我们还发现PKC^调节MAP激酶磷酸酶-1（MKP-1）仅在Fib-C中的表达，但是 不在fib-h中。导致PKQ解偶联的生化途径；根据MKP-1的调节 FIB-H中的表达尚不清楚。理由问题将通过以下解决 具体目的：1）低氧肺高血压的发展导致外观 PKC¿的核定位，激活和目标特异性的成纤维细胞的； 2） PKC€作为生长调节剂的功能作用改变了，促进了增强 慢性低氧动物的成纤维细胞； 3）核PKC^介导的生长抑制 从从冒险室分离出的成纤维细胞中，MKP-1的活性不存在 长期缺氧动物。拟议的实验的成功完成将提供新的 对PKCF的作用的见解；肺血管疾病中的MKP-1，可能导致发展 改善了治疗由慢性缺氧引起的肺部疾病的治疗策略。