title: Hydrogen peroxide-mediated induction of SOD1 gene transcription is independent from Nrf2 in a cellular model of neurodegeneration.
abstract: BACKGROUND
  It is still unclear whether oxidative stress (OS) is a disease consequence or is directly involved in the etiology of neurodegenerative disorders (NDs) onset and/or progression; however, many of these conditions are associated with increased levels of oxidation markers and damaged cell components. Previously we demonstrated the accumulation of reactive oxygen species (ROS) and increased SOD1 gene expression in H2O2-treated SH-SY5Y cells, recapitulating pathological features of Amyotrophic Lateral Sclerosis (ALS). Since we observed a post-transcriptional regulation of SOD1 gene in this cellular model, we investigated the transcriptional regulation of SOD1 mRNA under oxidative stress (OS).
  
  
  RESULTS
  In response to H2O2 treatment, PolII increased its association to SOD1 promoter. Electrophoretic mobility shift assays and mass spectrometry analyses on SOD1 promoter highlighted the formation of a transcriptional complex bound to the ARE sequences. Western Blotting experiments showed that in our in vitro model, H2O2 exposure increases Nrf2 expression in the nuclear fraction while immunoprecipitation confirmed its phosphorylation and release from Keap1 inhibition. However, H2O2 treatment did not modify Nrf2 binding on SOD1 promoter, which seems to be regulated by different transcription factors (TFs).
  
  
  CONCLUSIONS
  Although our data suggest that SOD1 is transcriptionally regulated in response to OS, Nrf2 does not appear to associate with SOD1 promoter in this cellular model of neurodegeneration. Our results open new perspectives in the comprehension of two key antioxidant pathways involved in neurodegenerative disorders.
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy; Department of Brain and Behavioural Sciences, University of Pavia, Via Forlanini 9, 27100 Pavia, Italy. Electronic address: michela.dellorco@outlook.com.
authors.forename: Michela
authors.initials: M
authors.lastname: Dell'Orco
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy. Electronic address: pame.milani@gmail.com.
authors.forename: Pamela
authors.initials: P
authors.lastname: Milani
authors.affiliation: Institute of Molecular Genetics (IGM) CNR, Via Abbiategrasso 207, 27100 Pavia, Italy. Electronic address: arrigoni@ie-freiburg.mpg.de.
authors.forename: Laura
authors.initials: L
authors.lastname: Arrigoni
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy. Electronic address: orietta.pansarasa@mondino.it.
authors.forename: Orietta
authors.initials: O
authors.lastname: Pansarasa
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy. Electronic address: valentina.sardone@gmail.com.
authors.forename: Valentina
authors.initials: V
authors.lastname: Sardone
authors.affiliation: Filarete Foundation, Viale Ortles 22/4, 20139 Milan, Italy; Department of Veterinary Science and Public Health, University of Milan, via Celoria 10, 20133 Milano, Italy. Electronic address: elisa.maffioli@guest.unimi.it.
authors.forename: Elisa
authors.initials: E
authors.lastname: Maffioli
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy. Electronic address: francesca.polveraccio@gmail.com.
authors.forename: Francesca
authors.initials: F
authors.lastname: Polveraccio
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy; Department of Brain and Behavioural Sciences, University of Pavia, Via Forlanini 9, 27100 Pavia, Italy. Electronic address: matteo.bordoni02@universitadipavia.it.
authors.forename: Matteo
authors.initials: M
authors.lastname: Bordoni
authors.affiliation: Department of Brain and Behavioural Sciences, University of Pavia, Via Forlanini 9, 27100 Pavia, Italy; Division of General Neurology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100, Pavia, Italy. Electronic address: luca.diamanti@mondino.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Diamanti
authors.affiliation: Department of Brain and Behavioural Sciences, University of Pavia, Via Forlanini 9, 27100 Pavia, Italy; Division of General Neurology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100, Pavia, Italy. Electronic address: mauro.ceroni@mondino.it.
authors.forename: Mauro
authors.initials: M
authors.lastname: Ceroni
authors.affiliation: Institute of Molecular Genetics (IGM) CNR, Via Abbiategrasso 207, 27100 Pavia, Italy. Electronic address: peverali@igm.cnr.it.
authors.forename: Fiorenzo A
authors.initials: FA
authors.lastname: Peverali
authors.affiliation: Filarete Foundation, Viale Ortles 22/4, 20139 Milan, Italy; Department of Veterinary Science and Public Health, University of Milan, via Celoria 10, 20133 Milano, Italy. Electronic address: gabriella.tedeschi@unimi.it.
authors.forename: Gabriellla
authors.initials: G
authors.lastname: Tedeschi
authors.affiliation: Laboratory of Experimental Neurobiology, "C. Mondino" National Institute of Neurology Foundation, IRCCS, Via Mondino 2, 27100 Pavia, Italy. Electronic address: cristina.cereda@mondino.it.
authors.forename: Cristina
authors.initials: C
authors.lastname: Cereda
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics* / Q000473:pathology; D002460:Cell Line; D005786:Gene Expression Regulation / Q000235:genetics; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D047908:Intracellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics*; D000072019:Kelch-Like ECH-Associated Protein 1; D051267:NF-E2-Related Factor 2 / Q000096:biosynthesis* / Q000235:genetics; D009410:Nerve Degeneration / Q000139:chemically induced / Q000235:genetics* / Q000473:pathology; D018384:Oxidative Stress / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000187:drug effects; D012333:RNA, Messenger / Q000096:biosynthesis; D017382:Reactive Oxygen Species / Q000378:metabolism; D013482:Superoxide Dismutase / Q000096:biosynthesis* / Q000235:genetics; D000072105:Superoxide Dismutase-1; D014158:Transcription, Genetic
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; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C000606290:SOD1 protein, human; D006861:Hydrogen Peroxide; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1
keywords: Neurodegeneration; Nrf2; Oxidative stress; SOD1; Transcriptional regulation