title: Thrombin induces collagen gel contraction partially through PAR1 activation and PKC-epsilon.
abstract: The ability of fibroblasts to contract three-dimensional collagen gels has been used as an in vitro model of the tissue contraction which characterises both normal repair and fibrosis. Among its actions, thrombin can activate the protease-activated receptor (PAR)1 and, thereby, stimulate inflammation and repair. The current study evaluated whether thrombin could stimulate fibroblast-mediated collagen gel contraction by activating PAR1 and whether its downstream signalling depends on protein kinase C (PKC)-epsilon. Human foetal lung fibroblasts (HFL-1) were cultured in three-dimensional collagen gels and the area of the gels was measured by image analyser. Both thrombin and TFLLR, a selective PAR1 agonist, stimulated collagen gel contraction mediated by HFL-1. After RNA interference-mediated PAR1 knockdown in HFL-1, both thrombin and the PAR1 agonist-induced gel contraction were partially inhibited (by 22.4+/-2.2% and 17.6+/-5.6%, respectively). The gel contraction stimulated by thrombin was also reduced by a nonspecific PKC inhibitor and a calcium-independent PKC-epsilon inhibitor. Both thrombin and TFLLR significantly increased PKC-epsilon activity, and this effect was blocked by PAR1 knockdown. Thrombin stimulates collagen gel contraction at least partially through activation of protease-activated receptor 1 and protein kinase C-epsilon, and may contribute to tissue remodelling in inflammatory airway and lung diseases.
authors.affiliation: University of Nebraska Medical Center, 985125 Nebraska Medical Center, Omaha, NE, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Fang
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: S
authors.initials: S
authors.lastname: Abe
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: X Q
authors.initials: XQ
authors.lastname: Wang
authors.forename: T
authors.initials: T
authors.lastname: Kohyama
authors.forename: M
authors.initials: M
authors.lastname: Hashimoto
authors.forename: T
authors.initials: T
authors.lastname: Wyatt
authors.forename: S I
authors.initials: SI
authors.lastname: Rennard
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D003094:Collagen / Q000187:drug effects* / Q000502:physiology*; D005347:Fibroblasts / Q000187:drug effects* / Q000502:physiology; D005782:Gels / Q000737:chemistry; D006801:Humans; D066298:In Vitro Techniques; D008168:Lung / Q000166:cytology / Q000196:embryology; D009842:Oligopeptides / Q000494:pharmacology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000187:drug effects* / Q000378:metabolism; D051744:Protein Kinase C-epsilon; D051381:Rats; D044463:Receptor, PAR-1 / Q000187:drug effects* / Q000378:metabolism; D013917:Thrombin / Q000494:pharmacology*; D010975:Platelet Aggregation Inhibitors
chemical_list: D005782:Gels; D009842:Oligopeptides; D044463:Receptor, PAR-1; C483910:TFLLRNPNDK-NH2; D003094:Collagen; C497257:Prkce protein, rat; C497255:PRKCE protein, human; D011493:Protein Kinase C; D051744:Protein Kinase C-epsilon; D013917:Thrombin; D010975:Platelet Aggregation Inhibitors