绝经后骨质疏松症中NOX4/GPX4影响成骨细胞铁死亡机理研究

骨质疏松症是绝经后女性骨骼退变一个重要表现，近些年研究认为：体内铁蓄积是一个新发病因素。关于铁蓄积（铁代谢异常）最新研究提出：细胞铁死亡是铁蓄积重要作用机理，因为铁死亡与凋亡、自噬不同，是线粒体改变且有特殊挽救方法。故我们在骨代谢中开展了铁死亡相关预实验：①在人体骨和成骨细胞中均发现铁死亡现象；②在绝经后骨折患者骨组织蛋白质谱分析中发现：线粒体相关蛋白NOX4在骨松和正常两组间存在显著差异；③在细胞实验中发现：NOX4与铁死亡标志蛋白GPX4相互作用，NOX4存在铁反应元件。因此我们推测：铁蓄积可调控NOX4/GPX4导致成骨细胞铁死亡（骨量降低）。本项目拟运用基因编辑方法构建NOX4敲除动物、细胞模型，采用蛋白质谱、CHIP、Co-IP、双荧光报告基因、分子编辑等方法，观察铁蓄积对成骨细胞NOX4和GPX4影响途径，分析铁死亡与骨松之间逻辑关联，探讨铁死亡在绝经后骨质疏松症中的作用机理。

Osteoporosis is an important manifestation of skeletal degeneration in postmenopausal women. In recent years, studies have suggested that iron accumulation in the body is a new factor. The latest research on iron accumulation (iron metabolism abnormality) proposed that cell ferroptosis is an important mechanism of iron accumulation, because ferroptosis is different from apoptosis and autophagy, which is a mitochondrial change and has special rescue methods. Therefore, we carried out pre-experiments related to ferroptosis in bone metabolism: ① Ferroptosis was found in human bone and osteoblasts; ② In the analysis of protein profile of bone tissue of postmenopausal fracture patients, it was found that the mitochondrial related protein NOX4 was significantly different between the osteoporisis and normal groups; ③ It was found in cellular experiments that NOX4 interacts with the ferroptosis marker protein GPX4, and there are iron-responsive elements in NOX4 gene. Therefore, we speculated that iron accumulation can regulate NOX4 / GPX4 and lead to ferroptosis osteoblasts (decreased bone mass). This project intends to use gene editing methods to construct NOX4 knockout animals and cell models, and to use protein profiling, CHIP, Co-IP, dual fluorescent reporter genes, molecular editing and other methods to observe the effects of iron accumulation on osteoblast NOX4 and GPX4, and analyze the logical relationship between ferroptosis and osteoporosis，and to explore the mechanism of ferroptosis in postmenopausal osteoporosis.