Microflora Trigger Colitis in Mice Deficient in Selenium-Dependent Glutathione Peroxidase and Induce Gpx2 Gene Expression
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R. S. Esworthy
Abstract
Selenium-dependent glutathione peroxidase isoenzymes-1 and -2 are the major glutathione-dependent H2O2-reducing activities in the epithelium of the mid to lower gastrointestinal tract. The two isoenzymes protect mice against ileocolitis. We have found that luminal microflora are required for colitis to develop in mice deficient in GPX-1 and GPX-2 activity (GPX-DKO). Within 7 days of association with microflora, previously asymptomatic germfree GPX-DKO mice developed severe acute colitis while their littermates with at least one wildtype Gpx1 or Gpx2 gene remained virtually symptomfree. Microflora also affected Gpx2 gene expression. Gpx2, but not Gpx1, mRNA levels were elevated 4-5 fold in the ileum and colon in conventionally reared or microflora-associated adult mice compared with germ-free mice. Since the gastrointestinal tract microflora undergo major changes 2-3 weeks after birth, from relatively benign to a potentially stressful composition, we examined postnatal Gpx2 gene expression. The jejunal and ileal GPX-2 activity levels were low in two to three weekold mice and increased 5-7 fold during the next two weeks. GPX-2 activity levels were correlated with the mRNA levels. Colon Gpx2 mRNA levels held steady at about 50% of adult levels from 12-21 days of age but were several times higher than ileal levels. Our results suggest that ileal Gpx2 mRNA and GPX-2 activity levels are induced by luminal microflora. This response is consistent with a role for GPX as an antiinflammatory activity.
Copyright © 2003 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Glutathione, Related Enzymology, and Leopold Flohé
- 'Lest I Forget Thee, Glutathione...'
- Glutathione Pathways in the Brain
- The Role of Glutathione Peroxidases in Trypanosomatids
- Cytoprotection against Oxidative Stress and the Regulation of Glutathione Synthesis
- The Parasite-Specific Trypanothione Metabolism of Trypanosoma and Leishmania
- Glutathione – Functions and Metabolism in the Malarial Parasite Plasmodium falciparum
- Oxidative Stress Caused by Inactivation of Glutathione Peroxidase and Adaptive Responses
- Versatility of Selenium Catalysis in PHGPx Unraveled by LC/ESI-MS/MS
- Modulation of the Chymotrypsin-Like Activity of the 20S Proteasome by Intracellular Redox Status: Effects of Glutathione Peroxidase-1 Overexpression and Antioxidant Drugs
- Microflora Trigger Colitis in Mice Deficient in Selenium-Dependent Glutathione Peroxidase and Induce Gpx2 Gene Expression
- Recruitment of the Interleukin-1 Receptor (IL-1RI)-Associated Kinase IRAK to the IL-1RI Is Redox Regulated
- Kinetics and Redox-Sensitive Oligomerisation Reveal Negative Subunit Cooperativity in Tryparedoxin Peroxidase of Trypanosoma brucei brucei
- Testis-Specific Expression of the Nuclear Form of Phospholipid Hydroperoxide Glutathione Peroxidase (PHGPx)
- Selective Recognition of Peptide Sequences by Glutathione Transferases: A Possible Mechanism for Modulation of Cellular Stress-Induced Signaling Pathways
- Biosynthesis of Trypanothione in Trypanosoma brucei brucei
- Transcriptional Regulation of Cytosol and Membrane Alanyl-Aminopeptidase in Human T Cell Subsets
- Regulation of Gene Transcription by a Constitutively Active Mutant of Activating Transcription Factor 2 (ATF2)
- Solvent Isotope Effect on the Reaction Catalysed by the Pyruvate Dehydrogenase Complex from Escherichia coli
- Selective Induction of Liver Parenchymal Cell Heme Oxygenase-1 in Selenium-Deficient Rats
Articles in the same Issue
- Glutathione, Related Enzymology, and Leopold Flohé
- 'Lest I Forget Thee, Glutathione...'
- Glutathione Pathways in the Brain
- The Role of Glutathione Peroxidases in Trypanosomatids
- Cytoprotection against Oxidative Stress and the Regulation of Glutathione Synthesis
- The Parasite-Specific Trypanothione Metabolism of Trypanosoma and Leishmania
- Glutathione – Functions and Metabolism in the Malarial Parasite Plasmodium falciparum
- Oxidative Stress Caused by Inactivation of Glutathione Peroxidase and Adaptive Responses
- Versatility of Selenium Catalysis in PHGPx Unraveled by LC/ESI-MS/MS
- Modulation of the Chymotrypsin-Like Activity of the 20S Proteasome by Intracellular Redox Status: Effects of Glutathione Peroxidase-1 Overexpression and Antioxidant Drugs
- Microflora Trigger Colitis in Mice Deficient in Selenium-Dependent Glutathione Peroxidase and Induce Gpx2 Gene Expression
- Recruitment of the Interleukin-1 Receptor (IL-1RI)-Associated Kinase IRAK to the IL-1RI Is Redox Regulated
- Kinetics and Redox-Sensitive Oligomerisation Reveal Negative Subunit Cooperativity in Tryparedoxin Peroxidase of Trypanosoma brucei brucei
- Testis-Specific Expression of the Nuclear Form of Phospholipid Hydroperoxide Glutathione Peroxidase (PHGPx)
- Selective Recognition of Peptide Sequences by Glutathione Transferases: A Possible Mechanism for Modulation of Cellular Stress-Induced Signaling Pathways
- Biosynthesis of Trypanothione in Trypanosoma brucei brucei
- Transcriptional Regulation of Cytosol and Membrane Alanyl-Aminopeptidase in Human T Cell Subsets
- Regulation of Gene Transcription by a Constitutively Active Mutant of Activating Transcription Factor 2 (ATF2)
- Solvent Isotope Effect on the Reaction Catalysed by the Pyruvate Dehydrogenase Complex from Escherichia coli
- Selective Induction of Liver Parenchymal Cell Heme Oxygenase-1 in Selenium-Deficient Rats
