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Title: Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway

Abstract

Highlights: • eNOS activity is increased in BAECs exposed to X-rays. • ATM is involved in this increased eNOS activity. • HSP90 modulates the radiation-induced activation of ATM and eNOS. - Abstract: In this study, the involvement of ataxia telangiectasia mutated (ATM) kinase and heat shock protein 90 (HSP90) in endothelial nitric oxide synthase (eNOS) activation was investigated in X-irradiated bovine aortic endothelial cells. The activity of nitric oxide synthase (NOS) and the phosphorylation of serine 1179 of eNOS (eNOS-Ser1179) were significantly increased in irradiated cells. The radiation-induced increases in NOS activity and eNOS-Ser1179 phosphorylation levels were significantly reduced by treatment with either an ATM inhibitor (Ku-60019) or an HSP90 inhibitor (geldanamycin). Geldanamycin was furthermore found to suppress the radiation-induced phosphorylation of ATM-Ser1181. Our results indicate that the radiation-induced eNOS activation in bovine aortic endothelial cells is regulated by ATM and HSP90.

Authors:
; ; ;  [1];  [2];  [3];  [4];  [1]
  1. Laboratory of Radiation Biology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818 (Japan)
  2. Laboratory of Biochemistry, Department of Food and Cosmetic Science, Faculty of Bioindustry, Tokyo University of Agriculture, Abashiri 099-2493 (Japan)
  3. Department of Molecular and Medical Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194 (Japan)
  4. Department of Radiological Sciences, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194 (Japan)
Publication Date:
OSTI Identifier:
22416889
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 456; Journal Issue: 1; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ANIMAL CELLS; BIOLOGICAL RADIATION EFFECTS; CATTLE; DNA DAMAGES; HEAT-SHOCK PROTEINS; IRRADIATION; NITRIC OXIDE; PHOSPHORYLATION; PHOSPHOTRANSFERASES; SERINE; X RADIATION

Citation Formats

Nagane, Masaki, Yasui, Hironobu, Sakai, Yuri, Yamamori, Tohru, Niwa, Koichi, Hattori, Yuichi, Kondo, Takashi, and Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp. Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway. United States: N. p., 2015. Web. doi:10.1016/J.BBRC.2014.12.002.
Nagane, Masaki, Yasui, Hironobu, Sakai, Yuri, Yamamori, Tohru, Niwa, Koichi, Hattori, Yuichi, Kondo, Takashi, & Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp. Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway. United States. doi:10.1016/J.BBRC.2014.12.002.
Nagane, Masaki, Yasui, Hironobu, Sakai, Yuri, Yamamori, Tohru, Niwa, Koichi, Hattori, Yuichi, Kondo, Takashi, and Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp. Fri . "Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway". United States. doi:10.1016/J.BBRC.2014.12.002.
@article{osti_22416889,
title = {Activation of eNOS in endothelial cells exposed to ionizing radiation involves components of the DNA damage response pathway},
author = {Nagane, Masaki and Yasui, Hironobu and Sakai, Yuri and Yamamori, Tohru and Niwa, Koichi and Hattori, Yuichi and Kondo, Takashi and Inanami, Osamu, E-mail: inanami@vetmed.hokudai.ac.jp},
abstractNote = {Highlights: • eNOS activity is increased in BAECs exposed to X-rays. • ATM is involved in this increased eNOS activity. • HSP90 modulates the radiation-induced activation of ATM and eNOS. - Abstract: In this study, the involvement of ataxia telangiectasia mutated (ATM) kinase and heat shock protein 90 (HSP90) in endothelial nitric oxide synthase (eNOS) activation was investigated in X-irradiated bovine aortic endothelial cells. The activity of nitric oxide synthase (NOS) and the phosphorylation of serine 1179 of eNOS (eNOS-Ser1179) were significantly increased in irradiated cells. The radiation-induced increases in NOS activity and eNOS-Ser1179 phosphorylation levels were significantly reduced by treatment with either an ATM inhibitor (Ku-60019) or an HSP90 inhibitor (geldanamycin). Geldanamycin was furthermore found to suppress the radiation-induced phosphorylation of ATM-Ser1181. Our results indicate that the radiation-induced eNOS activation in bovine aortic endothelial cells is regulated by ATM and HSP90.},
doi = {10.1016/J.BBRC.2014.12.002},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 456,
place = {United States},
year = {Fri Jan 02 00:00:00 EST 2015},
month = {Fri Jan 02 00:00:00 EST 2015}
}
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