title: Cigarette smoke extract increases S-adenosylmethionine and cystathionine in human lung epithelial-like (A549) cells.
abstract: The effect of cigarette smoke extract (CSE) on S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and sulfur amino acid metabolism was examined in human lung epithelial-like (A549) cells exposed to various CSE concentrations (2.5-100%) for 24 or 48 h. Intracellular SAM and SAM/SAH ratio were elevated after exposure to CSE for 48 h. Cell SAH content decreased, but the effect was not consistent. Cellular cystathionine, cysteine, and methionine levels were increased after CSE exposure for 48h. Sub-acute exposure to CSE induced increases in cellular SAM and SAM/SAH ratio. The transsulfuration pathway was likely activated by CSE since cystathionine increased, potentially contributing to the increased total intracellular GSH content.
authors.affiliation: Department of Pediatrics, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, CO 80206, USA.
authors.forename: Mihalis I
authors.initials: MI
authors.lastname: Panayiotidis
authors.forename: Sally P
authors.initials: SP
authors.lastname: Stabler
authors.forename: Robert H
authors.initials: RH
authors.lastname: Allen
authors.forename: Aftab
authors.initials: A
authors.lastname: Ahmad
authors.forename: Carl W
authors.initials: CW
authors.lastname: White
mesh_terms: D000603:Amino Acids, Sulfur / Q000378:metabolism; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003540:Cystathionine / Q000378:metabolism*; D003545:Cysteine / Q000378:metabolism; D004247:DNA / Q000032:analysis; D005978:Glutathione / Q000032:analysis; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D008715:Methionine / Q000378:metabolism; D012435:S-Adenosylhomocysteine / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000378:metabolism*; D012906:Smoke; D013997:Time Factors; D014026:Nicotiana
chemical_list: D000603:Amino Acids, Sulfur; D012906:Smoke; D003540:Cystathionine; D012436:S-Adenosylmethionine; D004247:DNA; D012435:S-Adenosylhomocysteine; D008715:Methionine; D005978:Glutathione; D003545:Cysteine