Induction of gamma-glutamylcysteine synthetase by cigarette smoke is associated with AP-1 in human alveolar epithelial cells.
Increased levels of glutathione (GSH) occur in the epithelial lining fluid (ELF) of chronic cigarette smokers. Therefore we investigated the effect of cigarette smoke condensate solution (CSC) on GSH synthesis and the regulation of gamma-glutamylcysteine synthetase (gammaGCS) in human type II alveolar epithelial cells (A549). CSC exposure increased GSH levels, gammaGCS activity and gammaGCS heavy subunit (HS) mRNA, as well as increasing DNA binding of the activator protein-1 (AP-1) and the human antioxidant response element (hARE). Transfection of deletion constructs of the gammaGCS-HS promoter in a chloramphenicol acetyl transferase (CAT) reporter system revealed that an hARE, present within promoter, is not required for the CSC mediated induction. We conclude that CSC induction of gammaGCS-HS expression is associated with AP-1/AP-1-like responsive elements.
Respiratory Medicine Unit, Department of Medicine, Rayne Laboratory, University of Edinburgh, UK.
I
I
Rahman
C A
CA
Smith
M F
MF
Lawson
D J
DJ
Harrison
W
W
MacNee
D000975:Antioxidants / Q000494:pharmacology; D001665:Binding Sites; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D005721:Glutamate-Cysteine Ligase / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D005978:Glutathione / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D011401:Promoter Regions, Genetic; D011650:Pulmonary Alveoli / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000187:drug effects; D011994:Recombinant Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D012906:Smoke / Q000009:adverse effects*; D018808:Transcription Factor AP-1 / Q000187:drug effects / Q000378:metabolism*; D014157:Transcription Factors / Q000187:drug effects / Q000378:metabolism; D014158:Transcription, Genetic
D000975:Antioxidants; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012906:Smoke; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D005721:Glutamate-Cysteine Ligase; D005978:Glutathione