ROLE OF CYCLIC AMP IN CYST CELL PROLIFERATION

环AMP在囊肿细胞增殖中的作用

• 批准号: 6493080
• 负责人: JARED JAMES GRANTHAM
• 金额: $ 16.2万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6493080
• 关键词: G protein; MDCK cell; apoptosis; autosomal dominant trait; cell proliferation; clinical research; cyclic AMP; disease /disorder model; enzyme activity; epithelium; human subject; immunocytochemistry; kidney cell; laboratory mouse; laboratory rat; mitogen activated protein kinase; polycystic kidney; protein localization

Description: (Taken directly from the application) Autosomal dominant polycystic kidney disease (ADPKD) is a slowly progressive renal disorder characterized by the development and steady enlargement of innumerable epithelial cysts that are derived from renal tubules. Proliferation of tubule epithelial cells is an important process in the generation and enlargement of cysts. New evidence indicates that ADPKD cyst epithelial cells may be unusually sensitive to a mitogenic action of cyclic ANT. This project is based on our new findings that cAMP stimulates the in vitro proliferation of ADPKD cyst epithelial cells and that PD98059, a highly selective inhibitor of the mitogen-activated-ERK-pathway, blocks these effects of the nucleotide. By contrast, cells of normal human kidney cortex (HKC) do not proliferate in response to cAMP in vitro. The central thrust of this project is to test the hypothesis that: In ADPKD, renal cyst enlargement is accelerated by elevated levels of intracellular MAP. This nucleotide, through the activation of protein kinase A, stimulates the MAP kinase pathway leading to sustained epithelial mitogenesis and cellular proliferation. The following Specific Aims will test this hypothesis: 1) Epithelial cells from human ADPKD cysts and normal human kidney cortex (HKC), and cAMP sensitive and insensitive strains of NOCK cells will be used to determine the dependence of proliferation on intracellular concentrations of cAMP and the role of apoptosis in the overall proliferative response; 2) Determine the level of involvement of ERK 1,2, MEK and Raf-I in the cAMP-mediated increase in proliferation of responsive renal epithelial cells; 3) Determine the involvement of Rap-I and B-Raf in cAMP-mediated increase in proliferation of responsive renal epithelial cells; 4) Determine if changes in intracellular cAMP levels in situ alter the rate of disease progression in Han: SPRD rats and CD1 pCY mice with inherited forms of PKD. Achievement of these aims requires application of the techniques of molecular biology, cell biology, biochemistry, pharmacology and cellular and integrative physiology. These studies will yield new insights into the molecular mechanisms governing the enlargement of renal cysts and provide a framework for the design of therapeutic measures to combat the progressive destruction of renal parenchyma by cysts.

描述：(直接取自申请)常染色体显性遗传性多囊肾病(ADPKD)是一种进展缓慢的肾脏疾病，其特征是来自肾小管的无数上皮性囊肿的发展和稳定增大。肾小管上皮细胞的增殖是囊性病变发生和扩大的重要过程。新的证据表明，ADPKD囊上皮细胞可能对周期ANT的促有丝分裂作用异常敏感。这个项目是基于我们的新发现，即cAMP刺激ADPKD囊上皮细胞的体外增殖，而PD98059，一种高选择性的丝裂原激活ERK途径的抑制剂，阻断了核苷酸的这些作用。相比之下，正常人肾皮质(HKC)的细胞在体外不会对cAMP产生反应而增殖。该项目的中心目的是验证这样的假设：在ADPKD中，细胞内MAP水平的升高加速了肾囊肿的扩大。这种核苷酸通过蛋白激酶A的激活，刺激MAP激酶途径，导致持续的上皮有丝分裂和细胞增殖。1)人ADPKD囊上皮细胞和正常肾皮质(HKC)上皮细胞，以及cAMP敏感和不敏感的Nock细胞株将被用来确定细胞内cAMP浓度对增殖的依赖性以及细胞凋亡在整体增殖反应中的作用；2)确定ERK 1，2，MEK和Raf-I在cAMP介导的反应性肾上皮细胞增殖增加中的参与水平；3)确定Rap-I和B-Raf是否参与cAMP介导的反应性肾上皮细胞的增殖增加；4)确定细胞内cAMP水平的变化是否改变了遗传性PKD的HAN：SPRD大鼠和CD1 pCY小鼠的疾病进展速度。这些目标的实现需要应用分子生物学、细胞生物学、生物化学、药理学以及细胞和综合生理学等技术。这些研究将为控制肾囊肿大的分子机制提供新的见解，并为设计治疗措施提供一个框架，以对抗囊肿对肾实质的渐进性破坏。