title: Histamine stimulation of MMP-1(collagenase-1) secretion and gene expression in gastric epithelial cells: role of EGFR transactivation and the MAP kinase pathway.
abstract: OBJECTIVE
  GPCR stimulation by various ligands including histamine has been shown to transactivate the epidermal growth factor receptor (EGFR). This study examines the functional interactions between the H2 receptor and the EGFR in the regulation of matrix metalloproteinase-1 (MMP-1) secretion and gene expressions in cultured gastric epithelial cells.
  
  
  METHODS
  AGS cells were incubated for up to 24 h with either histamine or heparin binding-epidermal growth factor (HB-EGF) and MMP-1 release was determined by immunoassay. MMP-1 responses to histamine and HB-EGF were further tested by the use of H2 receptor antagonist, EGFR inhibitor and mitogen activator protein kinase (MAPK) inhibitor. The role of EGFR in MMP-1 release was further tested in cells transfected with specific EGFR siRNA. EGFR and ERK1/2 phosphorylation was determined by Western blot analysis. MMP-1 gene expression was determined by RNase protection assay (RPA).
  
  
  RESULTS
  Histamine and HB-EGF caused a dose-dependent release of MMP-1 with maximal responses that were 2.7- and 4.5-fold greater, respectively, than control, P<0.001. Famotidine prevented histamine-mediated MMP-1 release and AG1478 and EGFR siRNA completely inhibited MMP-1 secretion stimulated by both histamine and HB-EGF. Both histamine and HB-EGF stimulation of MMP-1 release was associated with activation of ERK1/2. MAPK inhibition also prevented histamine-and HB-EGF-induced MMP-1 secretion. Results of MMP-1 gene expression, either stimulatory or inhibitory, paralleled responses to MMP-1 secretion.
  
  
  CONCLUSIONS
  Histamine stimulation of the H2 receptor on AGS cells evoked MMP-1 secretion and gene up regulation that was dependent on transactivation of the EGFR and downstream activation of MAPK.
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Oklahoma Health Sciences Center and Oklahoma City Department of Veterans Affairs Medical Center, Oklahoma City, OK 73104, United States.
authors.forename: Hanumantha R
authors.initials: HR
authors.lastname: Ancha
authors.forename: Ravi R
authors.initials: RR
authors.lastname: Kurella
authors.forename: Charles A
authors.initials: CA
authors.lastname: Stewart
authors.forename: Gautam
authors.initials: G
authors.lastname: Damera
authors.forename: Brian P
authors.initials: BP
authors.lastname: Ceresa
authors.forename: Richard F
authors.initials: RF
authors.lastname: Harty
mesh_terms: D017364:Collagenases / Q000235:genetics* / Q000378:metabolism*; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D015738:Famotidine / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D066257:Heparin-binding EGF-like Growth Factor; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011799:Quinazolines; D034741:RNA, Small Interfering / Q000494:pharmacology; D013270:Stomach / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D013997:Time Factors; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics; D020032:Tyrphostins / Q000494:pharmacology
chemical_list: C587883:HBEGF protein, human; D066257:Heparin-binding EGF-like Growth Factor; D036341:Intercellular Signaling Peptides and Proteins; D047428:Protein Kinase Inhibitors; D011799:Quinazolines; D034741:RNA, Small Interfering; D020032:Tyrphostins; C101044:RTKI cpd; D015738:Famotidine; D006632:Histamine; D066246:ErbB Receptors; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D017364:Collagenases; C417249:collagenase 1