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: 6850816
• 负责人: Grazyna Nowak
• 金额: $ 21.9万
• 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 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6850816
• 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(摘自申请者的摘要)：本项目的长期目标 研究是为了阐明调节恢复的机制 肾近端小管细胞(RPTC)的生理功能 毒物引起的伤害。肾脏暴露于多种药物和毒物 导致急性肾功能衰竭(ARF)。RPTC是许多人的主要目标 肾毒物和损伤后肾脏的恢复通过 未损伤的RPTC的再生及亚致死性RPTC的修复 用于治疗ARF的治疗策略往往由于穷人而不成功 了解调节RPTC再生和修复的机制。这个 这项建议的目的是阐明蛋白质的三种主要同工酶的作用。 蛋白激酶C(PKCx、PKCo和PKCc)在RPTC功能修复中的作用 毒物引起的伤害。在我们的细胞再生和修复的体外模型中 (改良培养条件下的兔RPTC原代培养) 暴露于苯系物后恢复线粒体和转运功能 氧化剂(叔丁基氢过氧化氢，TBHP)，但不是卤代烃 (二氯乙烯-L-半胱氨酸)。对这些功能的抑制 接触TBHP后亚致死性RPTC伴发 蛋白激酶C(PKC)活性下降。TBHP前PKC的激活 暴露加速了恢复，而抑制PKC则阻止了 RPTC功能。DCVC暴露后缺乏RPTC修复伴随 DCVC暴露前PKC活性和PKC激活的持续抑制 促进RPTC功能的恢复。因此，这一点的中心假设 认为PKCA、PKC6和PKCc在血管修复中起着关键作用。 毒物损伤后RPTC的线粒体和转运功能 这些功能的恢复有赖于 PKC介导的信号转导。具体目标我将检查在 主要PKC同工酶的活性、蛋白水平和亚细胞定位 在中毒伤害后和恢复期间。《特定目标2》将演示 中毒后线粒体和运输功能的恢复 损伤通过PKCA、PKCS和/或PKCE介导。特定目标III将 确定参与调节RPTC功能恢复的途径 由PKC提供。完成这些目标将使我们更好地理解 PKC同工酶在RPTC功能修复中的作用 预防ARF或加速ARF恢复的代理。