title: Decline in DJ-1 and decreased nuclear translocation of Nrf2 in Fuchs endothelial corneal dystrophy.
abstract: OBJECTIVE
  This study sought to determine factors involved in nuclear factor erythroid 2-related factor 2 (Nrf2) regulation and their response to oxidative stress in Fuchs endothelial corneal dystrophy (FECD) and normal corneal endothelial cells (CECs).
  
  
  METHODS
  FECD corneal buttons were obtained from transplantations and normal human corneas from tissue banks. Oxidative stress was induced by tert-butyl hydroperoxide (tBHP). Protein and mRNA levels of Nrf2, DJ-1, p53, and Kelch-like ECH-associated protein1 (Keap1) were investigated using Western blotting and real-time PCR. Immunoprecipitation was used to detect levels of oxidized DJ-1 protein and Cullin 3- (Cul3)-regulated degradation of DJ-1 in immortalized FECD (FECDi) and normal CEC (HCECi) cell lines. Nrf2 subcellular localization was assessed by immunocytochemistry.
  
  
  RESULTS
  Nrf2 protein stabilizer, DJ-1, decreased significantly in FECD CECs compared with normal, whereas Nrf2 protein repressor, Keap1, was unchanged at baseline but increased under oxidative stress. Under oxidative stress, normal CECs upregulated DJ-1 protein synthesis, whereas FECD CECs did not. DJ-1 decline correlated with increased DJ-1 oxidative modification and carbonylation in FECDi as compared with HCECi. Increased labeling of immunoprecipitated DJ-1 protein with anti-Cul3 antibody indicated enhanced DJ-1 degradation in FECDi as compared with HCECi. Following tBHP treatment, Nrf2 translocated from cytoplasm to nuclei in normal CECs, whereas Nrf2 nuclear localization was not observed in FECD.
  
  
  CONCLUSIONS
  Decreased levels of DJ-1 in FECD at baseline and under oxidative stress correlate with impaired Nrf2 nuclear translocation and heightened cell susceptibility to apoptosis. Targeting the DJ-1/Nrf2 axis could yield a mechanism to slow CEC degeneration in FECD.
authors: Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA.
authors: Maya S
authors: MS
authors: Bitar
authors: Cailing
authors: C
authors: Liu
authors: Alireza
authors: A
authors: Ziaei
authors: Yuming
authors: Y
authors: Chen
authors: Thore
authors: T
authors: Schmedt
authors: Ula V
authors: UV
authors: Jurkunas
mesh_terms: D000368:Aged; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D016039:Corneal Transplantation; D004728:Endothelium, Corneal / Q000378:metabolism; D005260:Female; D005642:Fuchs' Endothelial Dystrophy / Q000378:metabolism* / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D000072019:Kelch-Like ECH-Associated Protein 1; D008297:Male; D051267:NF-E2-Related Factor 2 / Q000235:genetics / Q000378:metabolism*; D015513:Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D018384:Oxidative Stress / Q000187:drug effects; D000071617:Protein Deglycase DJ-1; D021381:Protein Transport / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D014019:Tissue Donors; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation; D020122:tert-Butylhydroperoxide / Q000494:pharmacology / Q000633:toxicity
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; C431364:KEAP1 protein, human; D000072019:Kelch-Like ECH-Associated Protein 1; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D015513:Oncogene Proteins; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; D020122:tert-Butylhydroperoxide; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1