title: Homocysteine injures vascular endothelial cells by inhibiting mitochondrial activity.
abstract: The aim of the present study was to investigate the role of homocysteine (Hcy) in the pathogenesis of pulmonary embolism (PE) and the associated molecular mechanisms in human umbilical vein endothelial cells (HUVECs). Hcy contents were detected with high-performance liquid chromatography. Apoptosis was detected by flow cytometry using Annexin-V staining. Cytochromecoxidase (COX) activity was assessed with an enzyme activity assay, and the expression levels of COX 17 were determined by western blot analysis. Intracellular reactive oxygen species levels were measured using a microplate reader with a fluorescence probe. The results demonstrated that, compared with the control group, the serum Hcy levels were significantly elevated in the PE group, suggesting that Hcy may be an indicator for PE. Following treatment with Hcy, the apoptosis rate was markedly elevated in HUVECs. Moreover, Hcy decreased COX activity and downregulated the expression of COX 17 in HUVECs. Furthermore, Hcy increased the ROS levels in these endothelial cells. However, all the above-mentioned physiopathological changes induced by Hcy in HUVECs could be restored by folic acid. In conclusion, the results of the present study demonstrated that Hcy inhibited COX activity, downregulated COX 17 expression, increased intracellular ROS levels and enhanced apoptosis in endothelial cells.
authors.affiliation: Intensive Care Unit, The People's Hospital of Laiwu, Laiwu, Shandong 271199, P.R. China.
authors.forename: Fengyong
authors.initials: F
authors.lastname: Yang
authors.affiliation: Intensive Care Unit, The People's Hospital of Laiwu, Laiwu, Shandong 271199, P.R. China.
authors.forename: Xiujing
authors.initials: X
authors.lastname: Qi
authors.affiliation: Intensive Care Unit, The People's Hospital of Laiwu, Laiwu, Shandong 271199, P.R. China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Gao
authors.affiliation: Intensive Care Unit, The People's Hospital of Laiwu, Laiwu, Shandong 271199, P.R. China.
authors.forename: Xingju
authors.initials: X
authors.lastname: Yang
authors.affiliation: Burn Center, Shanghai Hospital, Second Military Medical University, Shanghai 200433, P.R. China.
authors.forename: Xingfeng
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Intensive Care Unit, The People's Hospital of Laiwu, Laiwu, Shandong 271199, P.R. China.
authors.forename: Chonghao
authors.initials: C
authors.lastname: Duan
authors.affiliation: Department of Thoracic Surgery, The People's Hospital of Laicheng, Laiwu, Shandong 271199, P.R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Zheng
keywords: apoptosis; cytochrome c oxidase; homocysteine; pulmonary embolism; vascular endothelial cells