Differential response to acute low dose radiation in primary and immortalized endothelial cells. (October 2013)

• Record Type: Journal Article
• Authors: Rombouts, Charlotte; Aerts, An; Beck, Michael; De Vos, Winnok H.; Van Oostveldt, Patrick; Benotmane, Mohammed Abderrafi; Baatout, Sarah
• Is Part Of: International journal of radiation biology. Volume 89:Number 10(2013:Oct.)
• Page Start: 841
• Page End: 850
• Publication Date: 2013-10
• Subjects: Radiation -- Physiological effect -- Periodicals; Radiobiology -- Periodicals; 571.45
• DOI: 10.3109/09553002.2013.806831
• Languages: English
• ISSNs: 0955-3002

Abstract

<abstract> <title>Abstract</title> <p> <italic>Purpose</italic>: The low dose radiation response of primary human umbilical vein endothelial cells (HUVEC) and its immortalized derivative, the EA.hy926 cell line, was evaluated and compared.</p> <p> <italic>Material and methods:</italic> DNA damage and repair, cell cycle progression, apoptosis and cellular morphology in HUVEC and EA.hy926 were evaluated after exposure to low (0.05–0.5 Gy) and high doses (2 and 5 Gy) of acute X-rays.</p> <p> <italic>Results</italic>: Subtle, but significant increases in DNA double-strand breaks (DSB) were observed in HUVEC and EA.hy926 30 min after low dose irradiation (0.05 Gy). Compared to high dose irradiation (2 Gy), relatively more DSB/Gy were formed after low dose irradiation. Also, we observed a dose-dependent increase in apoptotic cells, down to 0.5 Gy in HUVEC and 0.1 Gy in EA.hy926 cells. Furthermore, radiation induced significantly more apoptosis in EA.hy926 compared to HUVEC.</p> <p> <italic>Conclusions</italic>: We demonstrated for the first time that acute low doses of X-rays induce DNA damage and apoptosis in endothelial cells. Our results point to a non-linear dose-response relationship for DSB formation in endothelial cells. Furthermore, the observed difference in radiation-induced apoptosis points to a higher radiosensitivity of EA.hy926 compared to HUVEC, which should be taken into account when using these cells as models for studying the endothelium radiation response.</p> </abstract>