title: The role of bronchial epithelial cell apoptosis in the pathogenesis of COPD.
abstract: There is an increased airway inflammation in the pathogenesis of chronic obstructive pulmonary disease (COPD), and it has been suggested that there may also be problem in the apoptosis and renewal of cells. However, there are limited human airway cell studies, in particular those from larger airways such as bronchi. We cultured primary human bronchial epithelial cells (HBECs) from bronchial explants of smokers (n = 6) without COPD and smokers with COPD (n = 8). Apoptosis was studied by fluorescence activated cell sorting. qRT-PCR was used to assess mRNA expression for proteins involving apoptosis including p21(CIP1/WAF1), p53, caspase-8 and caspase-9. Although there was no difference in the rate of viable cells between cells from smokers and COPDs, the level of early apoptotic cells was significantly increased in COPD cells [mean ± standard error of mean (SEM) = 4.86 ± 3.2 %, p = 0.015] as compared to smokers (mean ± SEM = 2.71 ± 1.62 %). In contrast, the rate of late apoptotic cells was significantly decreased in COPD cells (mean ± SEM = 9.82 ± 5.71 %) comparing to smokers (mean ± SEM = 15.21 ± 5.08 %, p = 0.003). Although expression of mRNA for p21(CIP1/WAF1) and caspase-9 was similar in both groups, p53 and caspase-8 mRNA expression was significantly greater in COPD cells. These findings suggest that HBEC apoptosis is increased in COPD, and that this involves p53 and caspase-8 pathways.
authors.affiliation: Department of Medical Biology, Faculty of Medicine, School of Medicine, Mustafa Kemal University, 31034, Hatay, Turkey, bgogebakan@gmail.com.
authors.forename: B
authors.initials: B
authors.lastname: Gogebakan
authors.forename: R
authors.initials: R
authors.lastname: Bayraktar
authors.forename: M
authors.initials: M
authors.lastname: Ulaslı
authors.forename: S
authors.initials: S
authors.lastname: Oztuzcu
authors.forename: D
authors.initials: D
authors.lastname: Tasdemir
authors.forename: H
authors.initials: H
authors.lastname: Bayram
mesh_terms: D000328:Adult; D000368:Aged; D017209:Apoptosis; D001980:Bronchi / Q000166:cytology / Q000378:metabolism*; D053181:Caspase 8 / Q000235:genetics / Q000378:metabolism; D053453:Caspase 9 / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000235:genetics / Q000473:pathology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012907:Smoking; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053181:Caspase 8; D053453:Caspase 9