Acrolein inhibits cytokine gene expression by alkylating cysteine and arginine residues in the NF-kappaB1 DNA binding domain.
Cigarette smoke is a potent inhibitor of pulmonary T cell responses, resulting in decreased immune surveillance and an increased incidence of respiratory tract infections. The alpha,beta-unsaturated aldehydes in cigarette smoke (acrolein and crotonaldehyde) inhibited production of interleukin-2 (IL-2), IL-10, granulocyte-macrophage colony-stimulating factor, interferon-gamma, and tumor necrosis factor-alpha by human T cells but did not inhibit production of IL-8. The saturated aldehydes (acetaldehyde, propionaldehyde, and butyraldehyde) in cigarette smoke were inactive. Acrolein inhibited induction of NF-kappaB DNA binding activity after mitogenic stimulation of T cells but had no effect on induction of NFAT or AP-1. Acrolein inhibited NF-kappaB1 (p50) binding to the IL-2 promoter in a chromatin immunoprecipitation assay by >99%. Using purified recombinant p50 in an electrophoretic mobility shift assay, we demonstrated that acrolein was 2000-fold more potent than crotonaldehyde in blocking DNA binding to an NF-kappaB consensus sequence. Matrix-assisted laser desorption/ionization time-of-flight and tandem mass spectrometry demonstrated that acrolein alkylated two amino acids (Cys-61 and Arg-307) in the DNA binding domain. Crotonaldehyde reacted with Cys-61, but not Arg-307, whereas the saturated aldehydes in cigarette smoke did not react with p50. These experiments demonstrate that aldehydes in cigarette smoke can regulate gene expression by direct modification of a transcription factor.
Lambert
Cherie
C
Division of Allergy and Clinical Immunology, Department of Medicine, University of Colorado at Denver and Health Sciences Center, Denver, Colorado 80262, USA. Cherie.Lambert@uchsc.edu
Li
Jimei
J
Jonscher
Karen
K
Yang
Teng-Chieh
TC
Reigan
Philip
P
Quintana
Megan
M
Harvey
Jean
J
Freed
Brian M
BM
D000171:Acrolein / Q000494:pharmacology*; D000447:Aldehydes / Q000494:pharmacology; D001120:Arginine / Q000276:immunology / Q000378:metabolism; D002478:Cells, Cultured; D003545:Cysteine / Q000276:immunology / Q000378:metabolism; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D004247:DNA / Q000276:immunology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D008168:Lung / Q000276:immunology / Q000378:metabolism; D052002:NF-kappa B p50 Subunit / Q000276:immunology / Q000378:metabolism*; D050778:NFATC Transcription Factors / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding; D012141:Respiratory Tract Infections / Q000276:immunology / Q000378:metabolism; D012906:Smoke / Q000009:adverse effects; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D014026:Nicotiana / Q000009:adverse effects; D018808:Transcription Factor AP-1 / Q000276:immunology / Q000378:metabolism
D000447:Aldehydes; D016207:Cytokines; D052002:NF-kappa B p50 Subunit; D050778:NFATC Transcription Factors; D012906:Smoke; D018808:Transcription Factor AP-1; D000171:Acrolein; D004247:DNA; D001120:Arginine; C012796:2-butenal; D003545:Cysteine