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Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.

This study investigated glutathione (GSH) homeostasis in human lung epithelial cells (A549) exposed to crocidolite. Exposure of A549 cells to 3 micrograms/cm2 crocidolite resulted in a decrease in intracellular reduced glutathione by 36% without a corresponding increase in GSH disulfide. After a 24-...

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Detalles Bibliográficos
Autores principales: Golladay, S A, Park, S H, Aust, A E
Formato: Texto
Lenguaje:English
Publicado: 1997
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470152/
https://www.ncbi.nlm.nih.gov/pubmed/9400737
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author Golladay, S A
Park, S H
Aust, A E
author_facet Golladay, S A
Park, S H
Aust, A E
author_sort Golladay, S A
collection PubMed
description This study investigated glutathione (GSH) homeostasis in human lung epithelial cells (A549) exposed to crocidolite. Exposure of A549 cells to 3 micrograms/cm2 crocidolite resulted in a decrease in intracellular reduced glutathione by 36% without a corresponding increase in GSH disulfide. After a 24-hr exposure to crocidolite, 75% of the intracellular GSH lost was recovered in the extracellular medium, of which 50% was in reduced form. Since the half-life of reduced GSH in culture medium was less than 1 hr, this suggests that reduced GSH was released continuously from the cells after treatment. The release of GSH did not appear to result from nonspecific membrane damage, as there was no concomitant release of lactate dehydrogenase or 14C-adenine from loaded cells after crocidolite treatment for 24 hr. Crocidolite exposure resulted in the formation of S-nitrosothiols but no increase in the level of GSH-protein mixed disulfides or GSH conjugates. Exposure of A549 cells to crocidolite for 24 hr decreased gamma glutamylcysteine synthetase (gamma-GCS) activity by 47% without changes in the activities of GSH reductase, GSH peroxidase, GSH S-transferase, or glucose-6-phosphate dehydrogenase. Treatment of cells with crocidolite pretreated with the iron chelator desferrioxamine B resulted in the same level of intracellular GSH depletion and efflux and the same decrease in gamma-GCS activity as treatment with unmodified crocidolite, which suggests that iron-catalyzed reactions were not responsible for the GSH depletion.
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spelling pubmed-14701522006-06-01 Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos. Golladay, S A Park, S H Aust, A E Environ Health Perspect Research Article This study investigated glutathione (GSH) homeostasis in human lung epithelial cells (A549) exposed to crocidolite. Exposure of A549 cells to 3 micrograms/cm2 crocidolite resulted in a decrease in intracellular reduced glutathione by 36% without a corresponding increase in GSH disulfide. After a 24-hr exposure to crocidolite, 75% of the intracellular GSH lost was recovered in the extracellular medium, of which 50% was in reduced form. Since the half-life of reduced GSH in culture medium was less than 1 hr, this suggests that reduced GSH was released continuously from the cells after treatment. The release of GSH did not appear to result from nonspecific membrane damage, as there was no concomitant release of lactate dehydrogenase or 14C-adenine from loaded cells after crocidolite treatment for 24 hr. Crocidolite exposure resulted in the formation of S-nitrosothiols but no increase in the level of GSH-protein mixed disulfides or GSH conjugates. Exposure of A549 cells to crocidolite for 24 hr decreased gamma glutamylcysteine synthetase (gamma-GCS) activity by 47% without changes in the activities of GSH reductase, GSH peroxidase, GSH S-transferase, or glucose-6-phosphate dehydrogenase. Treatment of cells with crocidolite pretreated with the iron chelator desferrioxamine B resulted in the same level of intracellular GSH depletion and efflux and the same decrease in gamma-GCS activity as treatment with unmodified crocidolite, which suggests that iron-catalyzed reactions were not responsible for the GSH depletion. 1997-09 /pmc/articles/PMC1470152/ /pubmed/9400737 Text en
spellingShingle Research Article
Golladay, S A
Park, S H
Aust, A E
Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title_full Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title_fullStr Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title_full_unstemmed Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title_short Efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
title_sort efflux of reduced glutathione after exposure of human lung epithelial cells to crocidolite asbestos.
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1470152/
https://www.ncbi.nlm.nih.gov/pubmed/9400737
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AT austae effluxofreducedglutathioneafterexposureofhumanlungepithelialcellstocrocidoliteasbestos