title: Decreased DJ-1 leads to impaired Nrf2-regulated antioxidant defense and increased UV-A-induced apoptosis in corneal endothelial cells.
abstract: OBJECTIVE
  To investigate the role of DJ-1 in Nrf2-regulated antioxidant defense in corneal endothelial cells (CECs) at baseline and in response to ultraviolet A (UV-A)-induced oxidative stress.
  
  
  METHODS
  DJ-1-deficient CECs were obtained by transfection of an immortalized normal human corneal endothelial cell line (HCECi) with DJ-1 small interfering RNA (siRNA) or by isolation of CECs from ex vivo corneas of DJ-1 knockout mice. Levels of reactive oxygen species (ROS), protein carbonyls, Nrf2 subcellular localization, Nrf2 target genes, and protein interaction between Keap1/Nrf2 and Cul3/Nrf2 were compared between normal and DJ-1-deficient CECs. Oxidative stress was induced by irradiating HCECi cells with UV-A, and cell death and levels of activated caspase3 and phospho-p53 were determined.
  
  
  RESULTS
  DJ-1 siRNA-treated cells exhibited increased levels of ROS production and protein carbonyls as well as a 2.2-fold decrease in nuclear Nrf2 protein when compared to controls. DJ-1 downregulation led to attenuated gene expression of Nrf2 and its target genes HO-1 and NQO1. Similar levels of Nrf2 inhibitor, Keap1, and Cul3/Nrf2 and Keap1/Nrf2 were observed in DJ-1 siRNA-treated cells as compared to controls. Ultraviolet A irradiation resulted in a 3.0-fold increase in cell death and elevated levels of activated caspase3 and phospho-p53 in DJ-1 siRNA-treated cells compared to controls.
  
  
  CONCLUSIONS
  Downregulation of DJ-1 impairs nuclear translocation of Nrf2, causing decreased antioxidant gene expression and increased oxidative damage. The decline in DJ-1 levels leads to heightened CEC susceptibility to UV-A light by activating p53-dependent apoptosis. Targeting the DJ-1-Nrf2 axis may provide a potential therapeutic approach for enhancing antioxidant defense in corneal endothelial disorders.
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Cailing
authors.initials: C
authors.lastname: Liu
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Yuming
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Irene E
authors.initials: IE
authors.lastname: Kochevar
authors.affiliation: Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.
authors.forename: Ula V
authors.initials: UV
authors.lastname: Jurkunas
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis / Q000502:physiology* / Q000528:radiation effects; D002478:Cells, Cultured; D015536:Down-Regulation; D042783:Endothelial Cells / Q000378:metabolism / Q000528:radiation effects; D004728:Endothelium, Corneal / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000172:deficiency / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D051267:NF-E2-Related Factor 2 / Q000378:metabolism*; D015513:Oncogene Proteins / Q000172:deficiency / Q000502:physiology*; D018384:Oxidative Stress / Q000502:physiology*; D000071617:Protein Deglycase DJ-1; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D047908:Intracellular Signaling Peptides and Proteins; D051267:NF-E2-Related Factor 2; D015513:Oncogene Proteins; D017382:Reactive Oxygen Species; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1
keywords: DJ-1; Nrf2; corneal endothelial cells; oxidative stress; ultraviolet A light
references.citation: Am J Pathol. 2010 Nov;177(5):2278-89
references.pmid: 20847286
references.citation: Photochem Photobiol Sci. 2013 Aug;12(8):1310-8
references.pmid: 23364620
references.citation: J Biol Chem. 2008 Feb 15;283(7):4022-30
references.pmid: 18042550
references.citation: J Biol Chem. 2006 Jul 28;281(30):20940-20948
references.pmid: 16731528
references.citation: Invest Ophthalmol Vis Sci. 2012 Aug 24;53(9):5806-13
references.pmid: 22836768
references.citation: Invest Ophthalmol Vis Sci. 2003 Feb;44(2):594-9
references.pmid: 12556388
references.citation: J Invest Dermatol. 2006 Mar;126(3):667-75
references.pmid: 16374481
references.citation: Exp Dermatol. 2010 Feb;19(2):81-8
references.pmid: 20067521
references.citation: Science. 1999 Dec 10;286(5447):2169-72
references.pmid: 10591651
references.citation: Free Radic Biol Med. 2006 Feb 15;40(4):641-50
references.pmid: 16458195
references.citation: Science. 2003 Jan 10;299(5604):256-9
references.pmid: 12446870
references.citation: Biochem Biophys Res Commun. 1997 Feb 13;231(2):509-13
references.pmid: 9070310
references.citation: Photochem Photobiol. 2003 Oct;78(4):361-71
references.pmid: 14626664
references.citation: Proc Natl Acad Sci U S A. 2007 Sep 11;104(37):14807-12
references.pmid: 17766438
references.citation: Diabetes. 2013 Dec;62(12):4088-97
references.pmid: 23974919
references.citation: Ophthalmology. 2007 Aug;114(8):1453-60
references.pmid: 17320180
references.citation: Free Radic Biol Med. 1995 Apr;18(4):721-30
references.pmid: 7750796
references.citation: Proc Natl Acad Sci U S A. 2004 Jul 13;101(28):10446-51
references.pmid: 15229324
references.citation: PLoS One. 2011 Apr 20;6(4):e18044
references.pmid: 21533127
references.citation: Oxid Med Cell Longev. 2013;2013:351895
references.pmid: 24489983
references.citation: Hum Mol Genet. 2012 Jul 1;21(13):3013-24
references.pmid: 22492997
references.citation: PLoS One. 2013 Aug 23;8(8):e73169
references.pmid: 24058414
references.citation: Redox Biol. 2014 Feb 23;2:535-62
references.pmid: 24634836
references.citation: Neurol Sci. 2003 Oct;24(3):159-60
references.pmid: 14598065
references.citation: Cell. 2009 May 1;137(3):413-31
references.pmid: 19410540
references.citation: J Histochem Cytochem. 2002 Mar;50(3):341-51
references.pmid: 11850437
references.citation: PLoS Genet. 2013 Apr;9(4):e1003412
references.pmid: 23593018
references.citation: Photochem Photobiol. 1999 Oct;70(4):380-90
references.pmid: 10546543
references.citation: Proc Natl Acad Sci U S A. 1994 Oct 11;91(21):9926-30
references.pmid: 7937919
references.citation: Transplantation. 1999 Mar 27;67(6):800-8
references.pmid: 10199726
references.citation: Invest Ophthalmol Vis Sci. 2008 Jul;49(7):2956-63
references.pmid: 18378575
references.citation: N Engl J Med. 2010 Sep 9;363(11):1016-24
references.pmid: 20825314
references.citation: Cornea. 1988;7(1):2-18
references.pmid: 3280235
references.citation: Cell Growth Differ. 2001 Feb;12(2):61-83
references.pmid: 11243467
references.citation: Free Radic Biol Med. 2013 Sep;64:4-11
references.pmid: 23880293
references.citation: J Biol Chem. 2010 Jul 9;285(28):21258-68
references.pmid: 20427290
references.citation: Proc Natl Acad Sci U S A. 2006 Oct 10;103(41):15091-6
references.pmid: 17015834
references.citation: PLoS One. 2012;7(11):e49083
references.pmid: 23185296
references.citation: Eur J Cancer. 1999 Dec;35(14):2003-9
references.pmid: 10711242
references.citation: Mol Cell Proteomics. 2012 Jun;11(6):M111.015032
references.pmid: 22207702
references.citation: Eur J Neurosci. 2010 Mar;31(6):967-77
references.pmid: 20377612
references.citation: Diabetologia. 2014 Jan;57(1):204-13
references.pmid: 24186494
references.citation: Arch Biochem Biophys. 2006 Oct 1;454(1):7-15
references.pmid: 16962985
references.citation: PLoS One. 2012;7(7):e40501
references.pmid: 22792356
references.citation: Invest Ophthalmol Vis Sci. 2013 Oct 15;54(10):6724-34
references.pmid: 24030461
references.citation: Am J Respir Crit Care Med. 2008 Sep 15;178(6):592-604
references.pmid: 18556627
references.citation: J Biochem Mol Toxicol. 2008 Feb;22(1):63-76
references.pmid: 18273910
references.citation: Invest Ophthalmol Vis Sci. 2011 Dec 02;52(13):9291-7
references.pmid: 22064994
references.citation: J Biol Chem. 2006 Apr 21;281(16):10816-24
references.pmid: 16517609
references.citation: Proc Natl Acad Sci U S A. 2013 Apr 9;110(15):6085-90
references.pmid: 23530187