Expression of ICAM-1 and VCAM-1 in aortic endothelial cells of rats after exposure to Single-Walled Carbon Nanotubes
Objective To determine the sustainability of rat aortic vascular endothelial cells (RAEC) damage induced by single wall carbon nanotube and clarify the molecular mechanisms of vascular damage by the expression level of ICAM-1 and VCAM-1. Methods Aortic endothelial cells were exposed to different doses of SWCNT (0.80, 1.60, 3.12, 6.25, 12.50, 25.00, 50.00, 100.00, 200.0μg/ml) at different time. The oxidative damage and cell viability of aortic endothelial cells were evaluated by measuring the contents of GSH , LDH and MTT value respectively. Adhension phenomenon between RAEC and PBMC was observed by SEM and adhension assay was performed by detecting the protein content measured by Bradford method. Enzyme-linked immune assay and RNA Isolation and Reverse Transcription -Polymerase Chain Reaction (RT-PCR) methods were used to detect the expression of ICAM-1 and VCAM-1 of RAECs. Immunohistochemical method was used to detect the nucleus translocation of NF-κB/P65. Results The exposure to SWCNT can result in severe cell viability such as MTT value and oxidative damage of AECs such as GSH decreasing and LDH increasing with the dose and time of SWCNT exposure. Scanning electron-microscope directly showed RAEC-PBMC adhesion as well as the existence of the secondary tethering phenomenon. The ICAM-1 and VCAM-1 expression increased with the time and dosage of SWCNT exposure. SWCNT could directly induce the adhesion between RAEC to PBMC at almost the same time and in almost the same mode as ICAM-1 and VCAM-1 expressions. High-dose groups (50,100,200μg/ml) produced much severer damage and higher level of ICAM-1 and VCAM-1 proteins in endothelium than low-dose group (0.8μg/ml) (p＜0.01). The results of RT-PCR showed the expression of ICAM-1 and VCAM-1 mRNA also increased with the dose and time of SWCNTs exposure. The results of immunohistochemical showed that the nucleus translocation of NF-κB/P65 of SWCNT exposure (100μg/ml )was higher than that of control group and N-acetylcysteine pretreated before SWCNT exposure group (p＜0.05),Conclusions The direct exposure of SWCNT could promote RAEC to induce oxidative stress and then to express ICAM-1 and VCAM-1, hence provided physical basis for the adhesion of RAEC to PBMC. The occurrence of the secondary tethering further expanded and consolidated the adhesion. The nucleus translocation of NF-κB/P65 after SWCNT exposure can be inhibited by N-acetylcysteine which may indicate that the high expression of ICAM-1 and VCAM-1 mRNA mediated by oxidative stress in rat aortic endothelial cells may play an important role in SWCNT-induced vascular endothelium damage.
SWCNT rat aortic endothelial cells oxidative damage adhesion assay ICAM-1 VCAM-1 NF-κB/P65
Lin Zhiqing Xi Zhuge Chao Fuhuan Yang Danfeng Zhang Huashan Lin Bencheng Zhang Wei Liu Huanliang Sun Xin
Tianjin Insititute of Health and Environmental Medicine, Tianjin.P.R. China, 300050
国际会议
天津
英文
108-122
2007-07-17（万方平台首次上网日期，不代表论文的发表时间）