CALCIUM ION DEPENDENT PHOSPHOKINASE C ISOFORMS IN ADAPTATION/INFLAMATION

适应/炎症中钙离子依赖性磷酸激酶 C 亚型

• 批准号: 6296720
• 负责人: ANIRBAN BANERJEE
• 金额: $ 21.07万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6296720
• 关键词: adenosine; apoptosis; calcium ion; cytotoxicity; heart cell; heart function; human tissue; immunocytochemistry; inflammation; isozymes; laboratory rat; macrophage; myocardial ischemia /hypoxia; neutrophil; protein kinase C; protein localization; trauma

PKC isoforms differ in structure, CA++ dependency (cPKC) and regulation by lipids, but are present in all tissues examined. The specific combination of isoforms expressed are characteristic of that cell phenotype. This suggests that these isoforms do not have overlapping functions. Although functional cardioprotection induced by preconditioning is inhibited by PKC inhibitors, it is not clear what roles the isoforms play. Several PKC- linked stimuli, including Ca++ preconditioning, mediate different patterns of isoform translocation to different myocellular compartments. Several lines of evidence suggest that each receptor stimulated, isoform-profile encodes distinct mechanisms of protection. Comparison of different post- injury outcomes indicates that stimuli conferring preconditioning against post-ischemic mechanical dysfunction do not automatically protect against cell-death. Further, different degrees of functional protection against progressively severe ischemia indicates that preconditioning stimuli differ in their potency. Significantly, outcomes such as functional protection do not appear to be simply correlated with either the number of isoform engaged or the extent of translocation, indicating the importance of spatially precise isoform translocation, for the correct duration. This leads to the hypothesis that 'PKC' mediated mechanisms of protection or inflammation may be encoded by distinct combinations of PKC isoforms in specific compartments. In this proposal we will build on previous work on cardiac functional protection to 1. evaluate the efficacy of a set of preconditioning stimuli against cardiac apoptosis and infarction that occurs after severe ischemia. Map the spatial and temporal translocation for each isoform engaged by this set of cardiac stress, receptor, and direct PKC-linked stimuli. 3. Determine the specific role of the cPKC isoforms in mediating mechanisms of cardioprotection against post-ischemic dysfunction, infarction and apoptosis. Several heart cells including resident leukocytes express cPKC isoforms. Neutrophils and macrophages are important in systemic post-traumatic inflammation and when stimulated by appropriate receptor, are known to involves PKC in their cytotoxic functions. We will therefore investigate whether PKC linked receptors also translocate unique isoform profiles in these inflammatory leukocytes, by 4. determining the spatial and temporal translocation of isoforms after prototypic inflammatory stimuli and 5. assessing the role of the cPKC isoforms in mediating the cytotoxicity of appropriately stimulated isolated human neutrophils and rat macrophages.

PKC 同工型在结构、CA++ 依赖性 (cPKC) 和调节方面有所不同 脂质，但存在于所有检查的组织中。具体组合 表达的亚型是该细胞表型的特征。这 表明这些亚型不具有重叠的功能。虽然 预适应诱导的功能性心脏保护被 PKC 抑制 抑制剂，目前尚不清楚异构体发挥什么作用。几个 PKC- 相关刺激，包括 Ca++ 预处理，介导不同的模式 异构体易位到不同的肌细胞区室。一些 一系列证据表明，每个受体都受到刺激，亚型分布 编码不同的保护机制。不同后期的比较 损伤结果表明，刺激会导致预适应 缺血后机械功能障碍不会自动预防 细胞死亡。此外，不同程度的功能保护 逐渐严重的缺血表明预处理刺激 它们的效力不同。值得注意的是，诸如功能性等结果 保护似乎并不简单地与数量相关 参与的异构体或易位的程度，表明重要性 空间精确的同种型易位，持续时间正确。 这导致了“PKC”介导的保护机制的假设 或者炎症可能是由 PKC 同种型的不同组合编码的 特定隔间。在本提案中，我们将以之前的工作为基础 心脏功能保护 1. 评估一组的功效 针对心脏细胞凋亡和梗塞的预处理刺激 发生在严重缺血后。绘制空间和时间易位图 对于这组心脏应激、受体和参与的每个亚型 直接 PKC 相关刺激。 3.确定cPKC的具体作用 异构体在缺血后心脏保护介导机制中的作用 功能障碍、梗塞和细胞凋亡。 包括常驻白细胞在内的几种心脏细胞表达 cPKC 同工型。 中性粒细胞和巨噬细胞在系统性创伤后恢复中很重要 炎症并且当受到适当的受体刺激时，已知 PKC 参与其细胞毒功能。因此我们将调查 PKC 相关受体是否也会将独特的亚型谱易位 这些炎症白细胞，通过 4. 确定空间和时间 原型炎症刺激后异构体的易位和 5. 评估 cPKC 亚型在介导细胞毒性中的作用 适当刺激分离的人中性粒细胞和大鼠巨噬细胞。