Glutathione and Lung Fibrosis

谷胱甘肽和肺纤维化

• 批准号: 7691813
• 负责人: RUI-MING LIU
• 金额: $ 34.9万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-25 至 2012-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7691813
• 关键词: Acetylcysteine; Adenoviruses; Aerosols; Affect; Animal Model; Antioxidants; Attenuated; Bleomycin; Cells; Characteristics; Collagen; Cysteine; Deterioration; Disease; Fibroblasts; Fibrosis; Genetic; Glutamate-Cysteine Ligase; Glutathione; Glutathione Disulfide; Human; Immunoprecipitation; Inflammation; Inflammatory; Inflammatory Response; Intraperitoneal Injections; Knock-out; Knockout Mice; Label; Lung; Lung diseases; MAPK14 gene; MAPK8 gene; Matrix Metalloproteinases; Mediating; Modeling; Modification; Molecular; Mus; Oral Administration; Patients; Phosphoric Monoester Hydrolases; Phosphorylation; Physiologic pulse; Plasmin; Plasminogen; Plasminogen Activator; Plasminogen Activator Inhibitor 1; Play; Prevention strategy; Procollagen; Production; Proline; Protease Inhibitor; Protein phosphatase; Proteins; Reactive Oxygen Species; Respiratory physiology; Role; Saline; Signal Transduction; Small Interfering RNA; Staging; Structure of parenchyma of lung; Sulfhydryl Compounds; Supplementation; System; Techniques; Testing; Tetracyclines; Therapeutic; Therapeutic Effect; Time; Tranexamic Acid; Transforming Growth Factor beta; Transforming Growth Factor-Beta Induced Protein IGH3; Transgenic Mice; Virus; Wild Type Mouse; autocrine; collagenase; computerized data processing; cytokine; design; fibrogenesis; inhibitor/antagonist; insight; mRNA Expression; novel; overexpression; prevent; protein function; response

DESCRIPTION (provided by applicant): Lung fibrosis is a characteristic feature and terminal stage of many lung diseases with no efficacious treatment. The concentration of glutathione (GSH), the most abundant intracellular free thiol and an important antioxidant, is decreased in both experimental fibrosis and human fibrotic diseases. Importantly, aerosol or oral administration of GSH or N-acetylcysteine (NAC), a precursor of GSH, attenuates lung fibrosis in experimental fibrosis models and slows the deterioration of lung functions in patients with lung fibrotic diseases, indicating a potential therapeutic value of GSH/NAC for pulmonary fibrotic diseases. Nonetheless, the efficacy and mechanism underlying the therapeutic effects of GSH/NAC remains equivocal. Specifically, it is unclear whether GSH/NAC exerts its therapeutic effects by suppressing early-stage inflammatory response or whether it has direct antifibrotic activity and therefore can also block the progression of fibrosis in later stages of the disease. TGF-( is a most potent and ubiquitous profibrogenic cytokine. Our previous studies showed that TGF-( decreased GSH and increased reactive oxygen species (ROS) production in fibroblasts and in a lung fibrosis model while GSH/NAC supplementation inhibited TGF-(-stimulated collagen accumulation by blocking the expression of plasminogen activator inhibitor 1 (PAI-1), a protease inhibitor, and thus stimulating collagen degradation. Increasing GSH in lung ELF in tetracycline inducible lung specific glutamate cysteine ligase (GCL) transgenic mice also inhibits TGF-(-induced PAI-1 expression and lung fibrosis. Preliminary studies further show that TGF-( induces protein thiol modifications and inhibits the activity of JNK-directed phosphatases, associated with a stimulation of JNK/p38 phosphorylation while GSH blocks TGF-( activation of JNK and p38 MAPKs, which mediate TGF-( induction of PAI-1 expression. Therefore, we hypothesize that GSH/NAC can block fibrosis progression by attenuating TGF-('s fibrotic signaling and stimulating collagen degradation. Three specific aims are proposed that couple cell and animal models with pharmacologic and genetic approaches to elucidate the molecular mechanisms whereby GSH/NAC antagonizes TGF-(-induced lung fibrosis. Aim 1 will determine whether GSH/NAC can block the progression of late stage lung fibrosis induced by constitutively active TGF-( in GCL transgenic mice or NAC treated wild type mice. Aim 2 will determine whether GSH/NAC stimulates collagen degradation as well as the expression/activities of plasmin and the collagenases in TGF-( treated wild type and PAI-1 knockout mice. The bleomycin-induced lung fibrosis model will be used to further test our hypothesis. Aim 3 will focus on the molecular mechanisms whereby GSH/NAC antagonizes TGF-( fibrogenesis using mouse and primary human lung fibroblasts. Effect of GSH/NAC on TGF-(-induced thiol modifications and the activity of JNK/p38 directed phosphatases as well as the relationship between inhibition of the phosphatases and JNK/p38 activation/PAI-1 induction will be studied systematically. The results from these studies will provide new insight into the molecular mechanisms underlying TGF-('s fibrogenesis and GSH/NAC antifibrogenic effects, which will enable the design of more efficacious strategies for prevention and treatment of these fibroproliferative disorders. PROJECT NARRATIVE: Lung fibrosis is a characteristic feature and terminal stage of many lung diseases with no efficacious treatment. This project will test a novel hypothesis that glutathione, the most abundant intracellular free thiol and an important antioxidant, and N-acetyl cysteine (NAC), a precursor of GSH, can block fibrosis progression by attenuating the fibrogenic signals of TGF-(, a most potent and ubiquitous profibrogenic cytokine, and stimulating collagen degradation. The results from these studies will provide new insight into the molecular mechanisms underlying TGF-('s fibrogenesis and GSH/NAC antifibrogenic effects, which will enable the design of more efficacious strategies for prevention and treatment of these fibroproliferative disorders.

描述（申请人提供）： 肺纤维化是许多肺部疾病的特征和晚期阶段，目前尚无有效的治疗方法。谷胱甘肽 (GSH) 是细胞内最丰富的游离硫醇和重要的抗氧化剂，在实验性纤维化和人类纤维化疾病中，谷胱甘肽 (GSH) 的浓度都会降低。重要的是，气雾剂或口服 GSH 或 N-乙酰半胱氨酸（NAC）（GSH 的前体）可减轻实验纤维化模型中的肺纤维化，并减缓肺纤维化疾病患者肺功能的恶化，这表明 GSH/ 的潜在治疗价值NAC 用于肺纤维化疾病。尽管如此，GSH/NAC 治疗效果的功效和机制仍然不明确。具体而言，尚不清楚GSH/NAC是否通过抑制早期炎症反应发挥治疗作用，或者是否具有直接的抗纤维化活性，因此也可以阻止疾病后期纤维化的进展。 TGF-( 是一种最有效且普遍存在的促纤维化细胞因子。我们之前的研究表明，TGF-( 减少了成纤维细胞和肺纤维化模型中的 GSH 并增加了活性氧 (ROS) 的产生，而补充 GSH/NAC 则抑制了 TGF-(- 刺激)通过阻断纤溶酶原激活剂抑制剂 1 (PAI-1)（一种蛋白酶抑制剂）的表达，从而刺激肺 ELF 中的胶原蛋白降解，从而增加胶原蛋白的积累。四环素诱导的肺特异性谷氨酸半胱氨酸连接酶（GCL）转基因小鼠也能抑制TGF-(诱导的PAI-1表达和肺纤维化。初步研究进一步表明，TGF-(诱导蛋白硫醇修饰并抑制JNK定向磷酸酶的活性，相关刺激 JNK/p38 磷酸化，而 GSH 则阻断 TGF-( JNK 和 p38 MAPK 的激活，从而介导TGF-( 诱导 PAI-1 表达。因此，我们假设 GSH/NAC 可以通过减弱 TGF-( 的纤维化信号传导并刺激胶原蛋白降解来阻止纤维化进展。提出了三个具体目标，将细胞和动物模型与药理学和遗传学方法结合起来，以阐明 GSH/NAC 拮抗 TGF-诱导的肺纤维化的分子机制。目标 1 将确定 GSH/NAC 是否可以阻止晚期肺纤维化的进展GCL 转基因小鼠或 NAC 处理的野生型小鼠中由组成型活性 TGF-( 诱导的纤维化。目标 2 将确定 GSH/NAC 是否刺激胶原蛋白降解以及TGF-(处理的野生型和 PAI-1 敲除小鼠中纤溶酶和胶原酶的表达/活性。博莱霉素诱导的肺纤维化模型将用于进一步检验我们的假设。目标 3 将重点关注 GSH/NAC 的分子机制使用小鼠和原代人肺成纤维细胞拮抗 TGF-( 纤维形成。GSH/NAC 对 TGF-( 诱导的硫醇修饰和 JNK/p38 定向活性) 的影响将系统地研究磷酸酶以及磷酸酶的抑制与 JNK/p38 激活/PAI-1 诱导之间的关系。这些研究的结果将为 TGF-β 纤维形成和 GSH/NAC 抗纤维形成作用的分子机制提供新的见解，从而能够设计出更有效的策略来预防和治疗这些纤维增殖性疾病。项目叙述：肺纤维化是许多肺部疾病的特征和晚期阶段，没有有效的治疗方法，该项目将测试一个新的假设：谷胱甘肽是最丰富的细胞内游离硫醇。一种重要的抗氧化剂，N-乙酰半胱氨酸 (NAC)（GSH 的前体）可以通过减弱 TGF-（一种最有效且普遍存在的促纤维化细胞因子）的纤维化信号并刺激胶原蛋白降解来阻止纤维化进展。研究将为 TGF-β 纤维化和 GSH/NAC 抗纤维化作用的分子机制提供新的见解，这将有助于设计更有效的策略来预防和治疗这些疾病纤维增生性疾病。