Protein Kinase C in the Repair of Cellular Functions

蛋白激酶 C 在细胞功能修复中的作用

• 批准号: 6517907
• 负责人: Grazyna Nowak
• 金额: $ 21.51万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-01 至 2006-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6517907
• 关键词: acute renal failure; biological signal transduction; enzyme activity; isozymes; kidney; laboratory rabbit; protein kinase C; protein localization; regeneration; renal toxin; renal tubule; tissue /cell culture

DESCRIPTION (Adopted from the Applicant's Abstract): The long-term goal of this research is to elucidate the mechanisms that regulate the recovery of physiological functions in renal proximal tubular cells (RPTC) following toxicant-induced injury. Kidney exposure to a variety of drugs and toxicants results in acute renal failure (ARF). RPTC are the major target for many nephrotoxicants and the recovery of the kidney following injury occurs through the regeneration of the non-injured and repair of sublethally-injured RPTC. Therapeutic strategies used to treat ARF are often unsuccessful due to the poor understanding of the mechanisms regulating RPTC regeneration and repair. The goal of this proposal is to elucidate the role of 3 major isozymes of protein kinase C (PKCx, PKCo, and PKCc) in the repair of RPTC functions following toxicant-induced injury. In our in vitro model of cell regeneration and repair (primary cultures of rabbit RPTC grown in improved culture conditions) RPTC recover their mitochondrial and transport functions following exposure to an oxidant (tertbutylhydroperoxide, TBHP) but not a halocarbon (dichlorovinyl-L-cysteine, DCVC). Inhibition of these functions in sublethally-injured RPTC following TBHP exposure is accompanied with the decrease in protein kinase C (PKC) activity. Activation of PKC prior to TBHP exposure accelerates recovery while inhibition of PKC prevents the return of RPTC functions. Lack of RPTC repair after DCVC exposure is accompanied by sustained inhibition of PKC activity and PKC activation prior to DCVC exposure promotes recovery of RPTC functions. Therefore, the central hypothesis of this proposal is that PKCa, PKC6, and PKCc play a pivotal role in the repair of mitochondrial and transport functions of RPTC following toxicant injury and that the recovery of these functions depends on re-establishment of PKC-mediated signaling. Specific Aim I will examine the alterations in the activity, protein levels and subcellular localization of major PKC isozymes after toxicant injury and during recovery. Specific Aim II will demonstrate that the recovery of mitochondrial and transport functions following toxicant injury is mediated through PKCa, PKCS and/or PKCe. Specific Aim III will identify pathways that are involved in regulation of recovery of RPTC functions by PKC. Completion of these aims will result in a better understanding of the role of PKC isozymes in the repair of RPTC functions and may help to identify agents that protect against ARF or accelerate recovery from ARF.

描述（摘自申请人的摘要）：本项目的长期目标 研究的目的是阐明调节恢复的机制 肾近端小管细胞 (RPTC) 的生理功能 毒物引起的损伤。肾脏接触多种药物和毒物 导致急性肾衰竭（ARF）。 RPTC 是许多人的主要目标 肾毒物和损伤后肾脏的恢复是通过 未受伤的 RPTC 的再生和亚致死损伤的 RPTC 的修复。 用于治疗 ARF 的治疗策略常常因效果不佳而失败。 了解调节 RPTC 再生和修复的机制。这 该提案的目标是阐明蛋白质的 3 个主要同工酶的作用 激酶 C（PKCx、PKCo 和 PKCc）在 RPTC 功能修复中的作用 毒物引起的损伤。在我们的细胞再生和修复的体外模型中 （在改进的培养条件下生长的兔 RPTC 的原代培养物） RPTC 暴露于环境后恢复线粒体和运输功能 氧化剂（叔丁基过氧化氢，TBHP），但不是卤化碳 （二氯乙烯基-L-半胱氨酸，DCVC）。抑制这些功能 TBHP 暴露后亚致死损伤的 RPTC 伴随着 蛋白激酶 C (PKC) 活性降低。在 TBHP 之前激活 PKC 暴露可加速恢复，而抑制 PKC 可防止恢复 RPTC 功能。 DCVC 暴露后 RPTC 修复的缺乏伴随着 DCVC 暴露前持续抑制 PKC 活性和 PKC 激活 促进 RPTC 功能的恢复。因此，本研究的中心假设 建议认为 PKCa、PKC6 和 PKCc 在修复中发挥关键作用 毒物损伤后 RPTC 的线粒体和转运功能 这些功能的恢复取决于重建 PKC 介导的信号传导。具体目标 我将检查 主要 PKC 同工酶的活性、蛋白质水平和亚细胞定位 中毒后和恢复期间。具体目标 II 将展示 有毒物质后线粒体和运输功能的恢复 损伤是通过 PKCa、PKCS 和/或 PKCe 介导的。具体目标 III 将 确定参与 RPTC 功能恢复调节的途径 由 PKC 提供。完成这些目标将有助于更好地理解 PKC 同工酶在 RPTC 功能修复中的作用，可能有助于识别 预防 ARF 或加速 ARF 恢复的药物。