title: Stratifin-induced matrix metalloproteinase-1 in fibroblast is mediated by c-fos and p38 mitogen-activated protein kinase activation.
abstract: Previously, we have demonstrated that keratinocyte releasable stratifin, also known as 14-3-3 sigma protein, stimulates matrix metalloproteinase (MMP)-1 expression in dermal fibroblasts. In this study, we showed that stratifin induced fibroblast MMP-1 messenger ribonucleic acid (mRNA) and protein levels through p38 mitogen-activated protein kinase (MAPK). Our data indicated that treatment of dermal fibroblasts with stratifin resulted in rapid and transient upregulation of c-jun and c-fos mRNA levels. We also demonstrated that SB203580 (SB), a specific inhibitor of p38 MAPK activity, inhibited the activation of fibroblast MMP-1 mRNA expression by stratifin. Subsequently, western blot analysis revealed phosphorylation of p38 at 90 min after stratifin stimulation and this was decreased to approximately 50% of the maximum value by 120 min. Stratifin was demonstrated to increase MMP-1 protein levels starting at 4 h and reaching its peak at 12-24 h. Furthermore, SB significantly blocked the stratifin induction of MMP-1 protein levels (***p<0.005, n=3). Microarray analysis of stratifin-treated fibroblasts shows an increase in Elk4/Sap1 mRNA expression and this finding was confirmed by northern blot analysis. Our results indicate that stratifin markedly increase Elk4/Sap1 mRNA expression in a time-dependent fashion. In conclusion, stratifin stimulates fibroblast MMP-1 levels through the activation of c-fos and MAPK pathway.
authors.affiliation: Wound Healing Research Group, Department of Surgery, University of Alberta, Edmonton, AB, Canada.
authors.forename: Eugene
authors.initials: E
authors.lastname: Lam
authors.forename: Runhangiz T
authors.initials: RT
authors.lastname: Kilani
authors.forename: Yunyuan
authors.initials: Y
authors.lastname: Li
authors.forename: Edward E
authors.initials: EE
authors.lastname: Tredget
authors.forename: Aziz
authors.initials: A
authors.lastname: Ghahary
mesh_terms: D048948:14-3-3 Proteins; D014408:Biomarkers, Tumor / Q000378:metabolism* / Q000494:pharmacology; D002478:Cells, Cultured; D005092:Exonucleases / Q000378:metabolism* / Q000494:pharmacology; D005095:Exoribonucleases; D005347:Fibroblasts / Q000166:cytology / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000502:physiology; D020781:Matrix Metalloproteinase 1 / Q000235:genetics*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009363:Neoplasm Proteins / Q000378:metabolism* / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D011994:Recombinant Proteins / Q000378:metabolism / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
chemical_list: D048948:14-3-3 Proteins; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D011994:Recombinant Proteins; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D005092:Exonucleases; D005095:Exoribonucleases; C413442:SFN protein, human; D020781:Matrix Metalloproteinase 1