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Title: Glutathione peroxidase-1 inhibits UVA-induced AP-2{alpha} expression in human keratinocytes

Abstract

In this study, we found a role for H{sub 2}O{sub 2} in UVA-induced AP-2{alpha} expression in the HaCaT human keratinocyte cell line. UVA irradiation not only increased AP-2{alpha}, but also caused accumulation of H{sub 2}O{sub 2} in the cell culture media, and H{sub 2}O{sub 2} by itself could induce the expression of AP-2{alpha}. By catalyzing the removal of H{sub 2}O{sub 2} from cells through over-expression of GPx-1, induction of AP-2{alpha} expression by UVA was abolished. Induction of transcription factor AP-2{alpha} by UVA had been previously shown to be mediated through the second messenger ceramide. We found that not only UVA irradiation, but also H{sub 2}O{sub 2} by itself caused increases of ceramide in HaCaT cells, and C2-ceramide added to cells induced the AP-2{alpha} signaling pathway. Finally, forced expression of GPx-1 eliminated UVA-induced ceramide accumulation as well as AP-2{alpha} expression. Taken together, these findings suggest that GPx-1 inhibits UVA-induced AP-2{alpha} expression by suppressing the accumulation of H{sub 2}O{sub 2}.

Authors:
 [1];  [1];  [1];  [1];  [2];  [3]
  1. Free Radical and Radiation Biology Program, Department of Radiation Oncology, Carver College of Medicine, and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States)
  2. Dows Institute for Dental Research, College of Dentistry, University of Iowa, Iowa City, IA 52242 (United States)
  3. Free Radical and Radiation Biology Program, Department of Radiation Oncology, Carver College of Medicine, and Holden Comprehensive Cancer Center, University of Iowa, Iowa City, IA 52242 (United States). E-mail: frederick-domann@uiowa.edu
Publication Date:
OSTI Identifier:
20857944
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 351; Journal Issue: 4; Other Information: DOI: 10.1016/j.bbrc.2006.10.171; PII: S0006-291X(06)02436-3; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
63 RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS; ANTIOXIDANTS; BIOLOGICAL ACCUMULATION; BIOLOGICAL STRESS; CELL CULTURES; GLUTATHIONE; HYDROGEN PEROXIDE; IRRADIATION; OXYGEN; PEROXIDASES; SKIN; TRANSCRIPTION FACTORS; ULTRAVIOLET RADIATION

Citation Formats

Yu Lei, Venkataraman, Sujatha, Coleman, Mitchell C., Spitz, Douglas R., Wertz, Philip W., and Domann, Frederick E. Glutathione peroxidase-1 inhibits UVA-induced AP-2{alpha} expression in human keratinocytes. United States: N. p., 2006. Web.
Yu Lei, Venkataraman, Sujatha, Coleman, Mitchell C., Spitz, Douglas R., Wertz, Philip W., & Domann, Frederick E. Glutathione peroxidase-1 inhibits UVA-induced AP-2{alpha} expression in human keratinocytes. United States.
Yu Lei, Venkataraman, Sujatha, Coleman, Mitchell C., Spitz, Douglas R., Wertz, Philip W., and Domann, Frederick E. Fri . "Glutathione peroxidase-1 inhibits UVA-induced AP-2{alpha} expression in human keratinocytes". United States. doi:.
@article{osti_20857944,
title = {Glutathione peroxidase-1 inhibits UVA-induced AP-2{alpha} expression in human keratinocytes},
author = {Yu Lei and Venkataraman, Sujatha and Coleman, Mitchell C. and Spitz, Douglas R. and Wertz, Philip W. and Domann, Frederick E.},
abstractNote = {In this study, we found a role for H{sub 2}O{sub 2} in UVA-induced AP-2{alpha} expression in the HaCaT human keratinocyte cell line. UVA irradiation not only increased AP-2{alpha}, but also caused accumulation of H{sub 2}O{sub 2} in the cell culture media, and H{sub 2}O{sub 2} by itself could induce the expression of AP-2{alpha}. By catalyzing the removal of H{sub 2}O{sub 2} from cells through over-expression of GPx-1, induction of AP-2{alpha} expression by UVA was abolished. Induction of transcription factor AP-2{alpha} by UVA had been previously shown to be mediated through the second messenger ceramide. We found that not only UVA irradiation, but also H{sub 2}O{sub 2} by itself caused increases of ceramide in HaCaT cells, and C2-ceramide added to cells induced the AP-2{alpha} signaling pathway. Finally, forced expression of GPx-1 eliminated UVA-induced ceramide accumulation as well as AP-2{alpha} expression. Taken together, these findings suggest that GPx-1 inhibits UVA-induced AP-2{alpha} expression by suppressing the accumulation of H{sub 2}O{sub 2}.},
doi = {},
journal = {Biochemical and Biophysical Research Communications},
number = 4,
volume = 351,
place = {United States},
year = {Fri Dec 29 00:00:00 EST 2006},
month = {Fri Dec 29 00:00:00 EST 2006}
}
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