title: [Effects of endogeny polypeptide elafin on MUC5AC overexpression in human airway epithelial cells].
abstract: OBJECTIVE
  to explore the effects of endogeny polypeptide elafin on mucin (MUC) 5AC overexpression.
  
  
  METHODS
  eukaryotic expression vector pEGFP-N1-Elafin was constructed. HBE16 cells were cultured and divided into 6 groups:a control group, a cigarette smoke extract (CSE) stimulated group, a CSE and Elafin transfected group, a CSE and pEGFP-N1 transfected group, a single elafin transfected group, and a single pEGFP-N1 transfected group. After 24 h, the protein levels of phosphorylation Jun N-terminal kinase (p-JNK), phosphorylation extracellular signal-regulated kinase (p-ERK), p-P38 and inhibitor of NF-κB (IκB)α were detected by Western blot. The transcription activities of activator protein-1(AP-1) and nuclear factor κB (NF-κB) were detected by luciferase reporter gene detection system. The levels of MUC5AC protein and mRNA were detected by ELISA and RT-PCR.
  
  
  RESULTS
  in CSE group, there was a significant increase of MUC5AC protein (0.71 ± 0.04) mg/L and mRNA expression (0.81 ± 0.04), with elevation of p-JNK production (0.55 ± 0.03) microg/mg, p-ERK production (0.64 ± 0.06) microg/mg, p-c-Jun production (0.60 ± 0.07) microg/mg, AP-1 activity (7.49 ± 0.31) and NF-κB activity (4.42 ± 0.22), all significantly higher than those in the control group (t = 4.50 - 14.28, P < 0.01), and IκBα protein production was (0.27 ± 0.03) mg/L, significantly lower than that in the control group (t = 6.82, P = 0.008). Transfected recombinant elafin reduced MUC5AC protein (0.71 ± 0.04) mg/L and mRNA level (0.81 ± 0.04), decreased p-JNK (0.38 ± 0.04) microg/mg and p-ERK (0.31 ± 0.04) µg/mg production, inhibited AP-1 activity (2.60 ± 0.19) and NF-κB activity (2.55 ± 0.21), but increased IκBα protein (0.54 ± 0.03) µg/mg, compared with single CSE-stimulated group (all P < 0.05). p-P38 showed no significant change after CSE stimulation or transfection of elafin.
  
  
  CONCLUSIONS
  Endogeny polypeptide elafin may down-regulate MUC5AC overexpression, and this is through the inhibition of AP-1 and NF-κB activation via effects on mitogen-activated protein kinases and IκB pathway by Elafin.
authors.affiliation: Department of Respiratory Medicine, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Yu
authors.forename: Qi
authors.initials: Q
authors.lastname: Li
authors.forename: Juliy M
authors.initials: JM
authors.lastname: Perelman
authors.forename: Victor P
authors.initials: VP
authors.lastname: Kolosov
authors.forename: Xiang-Dong
authors.initials: XD
authors.lastname: Zhou
mesh_terms: D045744:Cell Line, Tumor; D053492:Elafin / Q000235:genetics*; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D055271:Mucin 5AC / Q000378:metabolism*; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000378:metabolism; D020545:Respiratory Mucosa / Q000166:cytology / Q000378:metabolism*; D012906:Smoke; D014026:Nicotiana; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014162:Transfection
chemical_list: D053492:Elafin; D020672:I-kappa B Proteins; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D012906:Smoke; D018808:Transcription Factor AP-1; D000072000:NF-KappaB Inhibitor alpha; D020928:Mitogen-Activated Protein Kinases