Transforming growth factor-β1 induces expression of human coagulation factor XII via Smad3 and JNK signaling pathways in human lung fibroblasts.
Coagulation factor XII (FXII) is a liver-derived serine protease involved in fibrinolysis, coagulation, and inflammation. The regulation of FXII expression is largely unknown. Transforming growth factor-beta1 (TGF-beta1) is a multifunctional cytokine that has been linked to several pathological processes, including tissue fibrosis by modulating procoagulant and fibrinolytic activities. This study investigated whether TGF-beta1 may regulate FXII expression in human lung fibroblasts. Treatment of human lung fibroblasts with TGF-beta1 resulted in a time-dependent increase in FXII production, activation of p44/42, p38, JNK, and Akt, and phosphorylation and translocation into the nucleus of Smad3. However, TGF-beta1-induced FXII expression was repressed only by the JNK inhibitor and JNK and Smad3 antisense oligonucleotides but not by MEK, p38, or phosphoinositide 3-kinase blockers. JNK inhibition had no effect on TGF-beta1-induced Smad3 phosphorylation, association with Smad4, and its translocation into the nucleus but strongly suppressed Smad3-DNA complex formation. FXII promoter analysis revealed that the -299/+1 region was sufficient for TGF-beta1 to induce FXII expression. Sequence analysis of this region detected a potential Smad-binding element at position -272/-269 (SBE-(-272/-269)). Chromatin immunoprecipitation and streptavidin pulldown assays demonstrated TGF-beta1-dependent Smad3 binding to SBE-(-272/-269). Mutation or deletion of SBE-(-272/-269) substantially reduced TGF-beta1-mediated activation of the FXII promoter. Clinical relevance was demonstrated by elevated FXII levels and its co-localization with fibroblasts in the lungs of patients with acute respiratory distress syndrome. Our results show that JNK/Smad3 pathway plays a critical role in TGF-beta1-induced FXII expression in human lung fibroblasts and implicate its possible involvement in pathological conditions characterized by elevated TGF-beta1 levels.
Department of Biochemistry, Faculty of Medicine, Justus-Liebig University, 35392 Giessen, Germany.
Ewa
E
Jablonska
Philipp
P
Markart
Dariusz
D
Zakrzewicz
Klaus T
KT
Preissner
Malgorzata
M
Wygrecka
D000818:Animals; D001992:Bronchoalveolar Lavage Fluid; D005174:Factor XII / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D008168:Lung / Q000378:metabolism*; D051379:Mice; D048055:Mitogen-Activated Protein Kinase 8 / Q000378:metabolism*; D041681:NIH 3T3 Cells; D016376:Oligonucleotides, Antisense / Q000737:chemistry; D011401:Promoter Regions, Genetic; D012128:Respiratory Distress Syndrome / Q000378:metabolism; D015398:Signal Transduction; D051900:Smad3 Protein / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
D016376:Oligonucleotides, Antisense; C497790:SMAD3 protein, human; D051900:Smad3 Protein; D053773:Transforming Growth Factor beta1; D005174:Factor XII; D048055:Mitogen-Activated Protein Kinase 8