Iron overload induced death of osteoblasts in vitro: involvement of the mitochondrial apoptotic pathway

作者：Qing Tian, Shilei Wu, Zhipeng Dai, Jingjing Yang, Jin Zheng, Qixin Zheng, Yong Liu · 发表于：PeerJ · 年份：2016 · DOI：10.7717/peerj.2611 · 被引用次数：79 · 研究领域：Bone Metabolism and Diseases、Iron Metabolism and Disorders、Trace Elements in Health

BACKGROUND: Iron overload is recognized as a new pathogenfor osteoporosis. Various studies demonstrated that iron overload could induce apoptosis in osteoblasts and osteoporosis in vivo. However, the exact molecular mechanisms involved in the iron overload-mediated induction of apoptosis in osteoblasts has not been explored. PURPOSE: In this study, we attempted to determine whether the mitochondrial apoptotic pathway is involved in iron-induced osteoblastic cell death and to investigate the beneficial effect of N-acetyl-cysteine (NAC) in iron-induced cytotoxicity. METHODS: The MC3T3-E1 osteoblastic cell line was treated with various concentrations of ferric ion in the absence or presence of NAC, and intracellular iron, cell viability, reactive oxygen species, functionand morphology changes of mitochondria and mitochondrial apoptosis related key indicators were detected by commercial kits. In addition, to further explain potential mechanisms underlying iron overload-related osteoporosis, we also assessed cell viability, apoptosis, and osteogenic differentiation potential in bone marrow-derived mesenchymal stemcells(MSCs) by commercial kits. RESULTS: Ferric ion demonstrated concentration-dependent cytotoxic effects on osteoblasts. After incubation with iron, an elevation of intracelluar labile iron levels and a concomitant over-generation of reactive oxygen species (ROS) were detected by flow cytometry in osteoblasts. Nox4 (NADPH oxidase 4), an important ROS producer, was also ...