Investigation of p21 in the molecular mechanisms of lung injury and pulmonary fibrosis

p21在肺损伤和肺纤维化分子机制中的研究

• 批准号: 15590813
• 负责人: FUJITA Masaki
• 金额: $ 1.92万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15590813/
• 关键词: lung injury; pulmonary fibrosis; apoptosis; p21; 肺腺維症; ブレオマイシン; lung injury; pulmonary fibrosis; apoptosis; p21; 肺腺維症; ブレオマイシン

1.Transforming Growth Factor-β1 as an Enhancer of Fas-mediated Apoptosis of Lung Epithelial CellsTransforming growth factor-β1(TGF-β1) has important roles in lung fibrosis and the potential to induce apoptosis in several types of cells. We previously demonstrated that apoptosis of lung epithelial cells induced by Fas ligation may be involved in the development of pulmonary fibrosis. Here we show that TGF-β1 induces apoptosis of primary cultured bronchiolar epithelial cells via caspase-3 activation and downregulation of cyclin-dependent kinase inhibitor p21. Concentrations of TGF-β1 that were not sufficient to induce apoptosis alone could enhance agonistic anti-Fas antibody or recombinant Fas ligand-mediated apoptosis of cultured bronchiolar epithelial cells. Soluble Fas ligand in the bronchoalveolar lavage fluid(BALF) from patients with idiopathic pulmonary fibrosis(IPF) also induced apoptosis of cultured bronchiolar epithelial cells that was significantly attenuated by anti-TGF-β anti … More body. Otherwise, BALF from patients with hypersensitivity pneumonitis(HP) could not induce apoptosis on bronchiolar epithelial cells despite its comparable amounts of soluble Fas ligand. The concentrations of TGF-β1 in BALF from patients with IPF were significantly higher compared with those in BALF from patients with HP or controls. Furthermore, co-incubation with the low concentration of TGF-β1 and HP BALF created pro-apoptotic effects comparable to the IPF BALF. In vivo, the administration of TGF-β1 could enhance Fas-mediated epithelial cell apoptosis and lung injury via caspase-3 activation in mice. Our results demonstrate a novel role of TGF-β1 in the pathophysiology of pulmonary fibrosis as an enhancer of Fas-mediated apoptosis of lung epithelial cells.2.In vivo gene transfer of mutant MCP-1 attenuates pulmonary fibrosisAlveolar epithelial cells are known to be present at the primary site of lung damage in pulmonary fibrosis. Apoptosis has been implicated as being involved in epithelial cell damage and pulmonary fibrosis. Since the cyclin-dependent kinase inhibitor p21 induces G1 arrest and DNA repair, and since it also prevents apoptosis in some cells, we hypothesized that p21 gene transfer may attenuate bleomycin-induced pulmonary fibrosis in mice, the pathogenesis of which likely involves epithelial cell apoptosis. Human p21 protein was expressed in mouse alveolar epithelial cells at 1 to 7 days in vitro and was detected predominantly in lung epithelial cells at 1 to 7 days in vivo after adenoviral transfer of the human p21 gene. Inflammatory cell infiltration and fibrosis had already begun at 7 days in this model. Adenoviral transfer of the human p21 gene at 7days after intratracheal instillation of bleomycin led to a decrease in the number of apoptotic cells, lung inflammation and fibrosis at 14 days. Therefore, the forced expression of p21 exerted both anti-apoptotic and anti-fibrotic effects, which would facilitate the ultimate goal of treatment for pulmonary fibrosis. Less

1。将生长因子-β1转化为FAS介导的肺上皮细胞凋亡的增强子，转化生长因子-β1（TGF-β1）在肺纤维化中具有重要作用，并且有可能诱导几种细胞中凋亡的潜力。我们先前证明，FAS结扎诱导的肺上皮细胞的凋亡可能与肺纤维化的发展有关。在这里，我们表明TGF-β1通过caspase-3激活和细胞周期蛋白依赖性激酶抑制剂p21诱导原代细支气管上皮细胞的凋亡。单独诱导凋亡的TGF-β1浓度可以增强激动性抗FAS抗体或重组FAS配体介导的培养的支气管上皮细胞的凋亡。来自特发性肺纤维化患者的支气管肺泡灌洗液（BALF）中的可溶性FAS配体也诱导了培养的支气管上皮细胞的凋亡，这些细胞上皮细胞被抗TGF-β抗抗体显着减弱。其他，尽管具有可比的固体FAS配体，但患有高敏性肺炎（HP）患者的BALF无法诱导支气管上皮细胞凋亡。与HP或对照患者的BALF患者相比，IPF患者的BALF中TGF-β1的浓度明显更高。此外，与低浓度的TGF-β1和HP BALF共同孵育产生了与IPF BALF相当的促凋亡效应。在体内，TGF-β1的给药可以通过小鼠中的caspase-3激活增强FAS介导的上皮细胞凋亡和肺损伤。我们的结果表明，TGF-β1在肺纤维化的病理生理学中的新作用是肺上皮细胞的FAS介导的凋亡的增强子。2。在突变MCP-1的体内基因转移肺部纤维纤维化的肺泡上皮细胞的肺部纤维化上皮细胞是Lung Firmary Fibriss的原始部位。凋亡已被实施为参与上皮细胞损伤和肺纤维化。由于细胞周期蛋白依赖性激酶抑制剂p21会影响G1停滞和DNA修复，并且由于它也可以预防某些细胞中的凋亡，因此我们假设p21基因转移可能会减弱小鼠博霉素诱导的小鼠肺纤维化，其病原体可能涉及上皮细胞凋亡。人p21蛋白在体外1至7天在小鼠肺泡上皮细胞中表达，并在人类p21基因转移后，在体内1至7天在肺上皮细胞中主要检测到。在该模型中，炎症细胞浸润和纤维化已经在7天开始开始。气管内滴注博来霉素后7天，人类p21基因的腺病毒转移导致凋亡细胞的数量减少，肺部注射和纤维化在14天时的数量减少。因此，p21的强制表达同时发挥了抗凋亡和抗纤维化作用，这将促进治疗肺纤维化的最终目标。较少的