title: Multiwall carbon nano-onions induce DNA damage and apoptosis in human umbilical vein endothelial cells.
abstract: Growing evidence has indicated the potential adverse effects on cardiovascular system of some nanomaterials, including fullerenes. In this study, we have evaluated the biological effects of multiwall carbon nano-onions (MWCNOs) (average size of 31.2 nm, ζ potential of 1.6 mV) on human umbilical vein endothelial cells (HUVECs). It was found that MWCNOs exhibited a dose-dependent inhibitory effect on cell growth; EC50 was 44.12 μg/mL. Thus, three concentrations were chosen (0.2, 1, and 5 μg/mL) for further experiments. Flow cytometry analysis revealed that 1 and 5 μg/mL MWCNOs could induce apoptosis in HUVECs, the apoptotic rates were 12% and 24% at 24 h after exposure. On the other hand, MWCNOs did not affect the cell cycle distribution during 24 h period. Using γH2AX foci formation as an indicator for DNA damage, it was shown that 5 μg/mL MWCNOs can induce γH2AX foci formation in HUVECs at 6, 12, and 24 h after treatment, whereas 0.2 μg/mL MWCNOs induced γH2AX foci formation only at 6 h after treatment. In addition, all three concentrations of MWCNOs induced the generation of reactive oxygen species (ROS), and inhibition of ROS generation can partially decrease the γH2AX foci formation induced by MWCNOs. Taken together, these data first suggested that MWCNOs can induce DNA damage and apoptosis in HUVECs, and that ROS might be involved in this process.
authors.affiliation: Department of Toxicology, Zhejiang University School of Public Health, 866 Yu-Hang-Tang Road, Hangzhou, Zhejiang 310058, China.
authors.forename: Yuying
authors.initials: Y
authors.lastname: Xu
authors.forename: Shuang-Ying
authors.initials: SY
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Gu
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.forename: Yi-Fan
authors.initials: YF
authors.lastname: Zheng
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.forename: Lihong
authors.initials: L
authors.lastname: Xu
authors.forename: Xin-Qiang
authors.initials: XQ
authors.lastname: Zhu
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D004249:DNA Damage; D005434:Flow Cytometry; D037741:Fullerenes / Q000633:toxicity*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D037741:Fullerenes; D017382:Reactive Oxygen Species