呼吸链复合体Ⅲ电子漏在电离辐射诱导肺成纤维细胞分化中的作用及其发生机制研究

项目名称： 呼吸链复合体Ⅲ电子漏在电离辐射诱导肺成纤维细胞分化中的作用及其发生机制研究

项目编号： No.81472912

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 陈晓红

作者单位： 中国人民解放军第三军医大学

项目金额： 75万元

中文摘要： 主要由肺成纤维细胞（LF）分化而来的肌成纤维细胞（MFB）在肺纤维化发生、发展过程中发挥着关键作用。新近发现，电离辐射诱导LF分化依赖于细胞活性氧（ROS）水平，而线粒体电子漏程度是决定细胞ROS水平的关键因素。以电子漏为切入点，探讨电离辐射诱导LF分化机制的相关研究，尚未见报道。基于前一自然基金项目发现呼吸链电子漏在电离辐射诱导LF分化中发挥了关键作用，且电子漏可能主要发生于呼吸链复合体Ⅲ，本项目拟应用细胞能量代谢实时测定、Blue native-page、RNAi等先进技术手段，结合动物和细胞模型，系统研究辐射后LF线粒体功能状态、复合体Ⅲ结构功能及超分子复合物稳定性、构成比的变化等科学问题，旨在明确呼吸链复合体Ⅲ底物端电子漏在电离辐射致LF分化中的重要地位，阐明复合体Ⅲ电子漏发生的生化及分子机制，为探寻放射性肺纤维化的防治新措施提供新思路。

中文关键词： 电子漏；成纤维细胞；电离辐射；分化；肺纤维化

英文摘要： Myofibroblasts，mainly differentiated from lung fibroblasts, play a pivotal role in the pathogenesis of pulmonary fibrosis.Recently,it was suggested that radiation-induced fibroblast differentiation into myofibroblasts was mediated by reactive oxygen species (ROS). It has been shown that the electron leak from mitochondrial respiratory chain is the primary source of ROS generation in nonphagocytic cells. However, the precise roles of the electron leak in radiation-related lung fibroblasts differentiation have yet to be determined. Sponsored by the Natural Science Foundation of China, our previous studies have shown that the increasing of electron leak from the respiratory chain play an important role in the fibroblast differentiation into myofibroblast induced by ionizing irradiation.Morever, the results of our study indicated that the electron leak may come from complex III of the respiratory chain. That improving of the electron leak may become the new strategy of inhibiting fibroblast differentiation induced by radiation. In this project, by using cellular bioenergetics analysis, blue native-PAGE, RNAi and other technological methods, the mitochondrial dysfunction,such as basal oxygen consumption,glycolysis rates, ATP production, and respiratory capacity induced by radiation will be explored. Also, the the changes of the components in complex Ⅲ and the construuction of supermolecular complex will be stuided. Based on the results of the study, the key role that the electron leak from complex Ⅲof the respiratory chain may contribute to driving fibroblasts differentiation will be elucidated. And the molecular mechanisms responsible for the electron leak in response to radiation will be clarified. Thus new strategies for the prevention and treatment of radiation-induced lung fibrosis will be provided from the experiments.

英文关键词： electron leak;fibroblasts;irradiation;differentiation;lung fibrosis