title: The implication of cigarette smoking and cessation on macrophage cholesterol efflux in coronary artery disease patients.
abstract: We investigated ATP-binding cassette transporters A1/G1 expression and function in mediating cholesterol efflux by examining the macrophages of cigarette-smoking patients with coronary artery disease (CAD) before and after smoking abstinence. Peripheral blood monocyte cells were collected from nonsmokers (n = 17), non-CAD (NCAD) smokers (n = 35), and CAD smokers (n = 32) before and after 3 months of smoking cessation. We found that the ABCA1 expression level was lower in macrophages from NCAD and CAD smokers than from nonsmokers at baseline. The ABCA1 function of mediating cholesterol efflux was reduced in NCAD and CAD smokers as compared with nonsmokers. After 3 months of smoking cessation, ABCA1 expression and function were improved in CAD smokers. However, ABCG1 expression and function did not change after smoking cessation. Furthermore, ABCA1 expression was inhibited by tar in human acute monocytic leukemia cell line THP-1-derived macrophages through the inhibition of liver X receptors. Nicotine and carbon monoxide did not inhibit ABCA1 expression. Our results indicate that chronic cigarette smoking impaired ABCA1-mediated cholesterol efflux in macrophages and that tobacco abstinence reversed the function and expression of ABCA1, especially in CAD patients. It was tobacco tar, rather than nicotine or carbon monoxide, that played a major role in the tobacco-induced disturbance of cellular cholesterol homeostasis.
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Li-Yang
authors.initials: LY
authors.lastname: Dou
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China.
authors.forename: Lian-Feng
authors.initials: LF
authors.lastname: Chen
authors.affiliation: Peking Union Medical College (PUMC) Hospital, PUMC and Chinese Academy of Medical Sciences, Beijing, China. Electronic address: xiaoweiyanpumc@aliyun.com.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Yan
mesh_terms: D064286:ATP Binding Cassette Transporter 1 / Q000096:biosynthesis; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D002784:Cholesterol / Q000097:blood*; D003324:Coronary Artery Disease / Q000097:blood* / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D008264:Macrophages / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000097:blood* / Q000473:pathology; D016540:Smoking Cessation; D013997:Time Factors
chemical_list: C577836:ABCA1 protein, human; D064286:ATP Binding Cassette Transporter 1; D002784:Cholesterol
keywords: ABCA1; macrophages; tobacco