title: High glucose and hydrogen peroxide increase c-Myc and haeme-oxygenase 1 mRNA levels in rat pancreatic islets without activating NFkappaB.
abstract: OBJECTIVE
  Hyperglycaemia and the pro-inflammatory cytokine IL-1beta induce similar alterations of beta cell gene expression, including up-regulation of c-Myc and haeme-oxygenase 1. These effects of hyperglycaemia may result from nuclear factor-kappa B (NFkappaB) activation by oxidative stress. To test this hypothesis, we compared the effects of IL-1beta, high glucose, and hydrogen peroxide, on NFkappaB DNA binding activity and target gene mRNA levels in cultured rat islets.
  
  
  METHODS
  Rat islets were pre-cultured for 1 week in serum-free RPMI medium containing 10 mmol/l glucose, and further cultured in glucose concentrations of 5-30 mmol/l plus various test substances. Islet NFkappaB activity was measured by ELISA and gene mRNA expression was measured by RT-PCR.
  
  
  RESULTS
  IL-1beta consistently increased islet NFkappaB activity and c-Myc, haeme-oxygenase 1, inducible nitric oxide synthase (iNOS), Fas, and inhibitor of NFkappaB alpha (IkappaBalpha) mRNA levels. In comparison, 1- to 7-day culture in 30 mmol/l instead of 10 mmol/l glucose stimulated islet c-Myc and haeme-oxygenase 1 expression without affecting NFkappaB activity or iNOS and IkappaBalpha mRNA levels. Fas mRNA levels only increased after 1 week in 30 mmol/l glucose. Overnight exposure to hydrogen peroxide mimicked the effects of 30 mmol/l glucose on haeme-oxygenase 1 and c-Myc mRNA levels without activating NFkappaB. On the other hand, the antioxidant N-acetyl-L-cysteine inhibited the stimulation of haeme-oxygenase 1 and c-Myc expression by 30 mmol/l glucose and/or hydrogen peroxide.
  
  
  CONCLUSIONS
  In contrast to IL-1beta, high glucose and hydrogen peroxide do not activate NFkappaB in cultured rat islets. It is suggested that the stimulation of islet c-Myc and haeme-oxygenase 1 expression by 30 mmol/l glucose results from activation of a distinct, probably oxidative-stress-dependent signalling pathway.
authors.affiliation: Endocrinology and Metabolism, Université Catholique de Louvain (UCL), 55.30, Avenue Hippocrate, 55, 1200, Brussels, Belgium.
authors.forename: H
authors.initials: H
authors.lastname: Elouil
authors.forename: A K
authors.initials: AK
authors.lastname: Cardozo
authors.forename: D L
authors.initials: DL
authors.lastname: Eizirik
authors.forename: J C
authors.initials: JC
authors.lastname: Henquin
authors.forename: J C
authors.initials: JC
authors.lastname: Jonas
mesh_terms: D000818:Animals; D005947:Glucose / Q000494:pharmacology*; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics*; D051547:Heme Oxygenase-1; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D016328:NF-kappa B / Q000378:metabolism*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics*; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics*; D051381:Rats; D014158:Transcription, Genetic / Q000187:drug effects*
chemical_list: D016328:NF-kappa B; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D006861:Hydrogen Peroxide; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; D005947:Glucose
references.citation: J Biol Chem. 2002 Feb 1;277(5):3680-5
references.pmid: 11714718
references.citation: Diabetes. 2003 Jan;52(1):1-8
references.pmid: 12502486
references.citation: Diabetes. 2001 Oct;50(10):2219-24
references.pmid: 11574401
references.citation: J Biol Chem. 2001 Sep 21;276(38):35375-81
references.pmid: 11457846
references.citation: Diabetes. 1995 Nov;44(11):1249-58
references.pmid: 7589820
references.citation: Diabetes. 1998 Jan;47(1):134-7
references.pmid: 9421388
references.citation: J Biol Chem. 2004 Mar 26;279(13):12126-34
references.pmid: 14688272
references.citation: J Biol Chem. 1999 May 14;274(20):14112-21
references.pmid: 10318828
references.citation: Endocrinology. 2004 Nov;145(11):5087-96
references.pmid: 15297438
references.citation: Diabetologia. 2003 Jan;46(1):3-19
references.pmid: 12637977
references.citation: Diabetes. 2002 Feb;51(2):413-23
references.pmid: 11812749
references.citation: J Endocrinol. 2003 Jul;178(1):101-9
references.pmid: 12844341
references.citation: Diabetes. 2001 Dec;50(12):2792-808
references.pmid: 11723063
references.citation: Diabetes. 2003 Mar;52(3):581-7
references.pmid: 12606496
references.citation: Biochem Biophys Res Commun. 2003 Dec 26;312(4):937-44
references.pmid: 14651961
references.citation: Nature. 2000 Apr 13;404(6779):787-90
references.pmid: 10783895
references.citation: Diabetologia. 1983 May;24(5):366-71
references.pmid: 6347784
references.citation: Biochem Pharmacol. 2002 Jan 15;63(2):139-48
references.pmid: 11841787
references.citation: J Biol Chem. 1998 Dec 11;273(50):33501-7
references.pmid: 9837930
references.citation: Diabetes. 2000 Mar;49(3):340-5
references.pmid: 10868954
references.citation: Diabetes. 2002 Jun;51(6):1793-804
references.pmid: 12031967
references.citation: Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12363-8
references.pmid: 12218186
references.citation: Diabetes. 2003 Feb;52(2):348-55
references.pmid: 12540607
references.citation: Diabetes. 2001 May;50(5):909-20
references.pmid: 11334433
references.citation: J Clin Invest. 1996 Dec 15;98(12):2805-12
references.pmid: 8981928
references.citation: Diabetologia. 2001 Dec;44(12):2115-33
references.pmid: 11793013
references.citation: Biochem Pharmacol. 2000 Jan 1;59(1):13-23
references.pmid: 10605930
references.citation: Biochem Pharmacol. 2002 Apr 1;63(7):1297-304
references.pmid: 11960606
references.citation: Cell. 2002 May 3;109(3):321-34
references.pmid: 12015982
references.citation: Diabetes. 2001 Aug;50(8):1741-8
references.pmid: 11473033
references.citation: Diabetologia. 1980 Jan;18(1):23-8
references.pmid: 6988263
references.citation: Endocrinology. 2000 Jan;141(1):153-62
references.pmid: 10614634
references.citation: Anal Biochem. 1997 Feb 15;245(2):154-60
references.pmid: 9056205
references.citation: Clin Ther. 2003;25 Suppl B:B32-46
references.pmid: 14553865
references.citation: Endocrinology. 2002 Feb;143(2):339-42
references.pmid: 11796484
references.citation: Endocrinology. 1998 Oct;139(10 ):4155-63
references.pmid: 9751495
references.citation: Diabetes. 2003 Jan;52(1):102-10
references.pmid: 12502499
references.citation: J Mol Endocrinol. 2000 Oct;25(2):169-93
references.pmid: 11013345
references.citation: J Clin Invest. 1997 Jan 1;99(1):144-50
references.pmid: 9011569
references.citation: Diabetologia. 1972 Aug;8(4):260-6
references.pmid: 4673942
references.citation: Diabetes. 2001 Sep;50(9):1983-91
references.pmid: 11522663
references.citation: Diabetes. 1996 Dec;45(12):1774-82
references.pmid: 8922365
references.citation: J Investig Med. 2001 Nov;49(6):566-71
references.pmid: 11730093
references.citation: J Biol Chem. 2001 Dec 28;276(52):48879-86
references.pmid: 11687580
references.citation: Endocrinology. 2002 Apr;143(4):1225-34
references.pmid: 11897677
references.citation: Metabolism. 2002 Oct;51(10):1340-7
references.pmid: 12370856
references.citation: J Mol Med (Berl). 2003 Aug;81(8):455-70
references.pmid: 12879149
references.citation: J Biol Chem. 2002 Aug 16;277(33):30010-8
references.pmid: 12011047
references.citation: Diabetologia. 2003 Sep;46(9):1234-44
references.pmid: 12898011
references.citation: Diabetes. 1999 Dec;48(12):2398-406
references.pmid: 10580429
references.citation: J Pediatr Endocrinol Metab. 2003 Jan;16(1):5-22
references.pmid: 12585335
references.citation: Am J Physiol Endocrinol Metab. 2004 Aug;287(2):E207-17
references.pmid: 15100093
references.citation: J Clin Invest. 2002 Sep;110(6):851-60
references.pmid: 12235117
references.citation: Proc Natl Acad Sci U S A. 1999 Sep 14;96(19):10857-62
references.pmid: 10485916
references.citation: Biochem Biophys Res Commun. 2000 Feb 16;268(2):541-6
references.pmid: 10679240
references.citation: Diabetes. 1995 Dec;44(12):1447-57
references.pmid: 7589853
references.citation: Diabetologia. 2003 Feb;46(2):250-4
references.pmid: 12627324