|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
E-mail contact: roseanne.greenberg@mssm.edu
Fibroblasts and myofibroblasts both participate in wound healing. Transforming growth factor beta (TGF
) induces fibroblasts to differentiate into myofibroblasts, whereas fibroblast growth factor and heparin (FGF/h) induce myofibroblasts to "de-differentiate" into fibroblasts. TGF
induces expression of smooth muscle alpha actin (SM
A) and incorporation into in stress fibers, a phenotype of differentiated myofibroblasts. Additionally, TGF
induces the expression of fibronectin and fibronectin integrins. Fibronectin-generated signals contribute to the TGF
-mediated myofibroblast differentiation. Because fibronectin signals are transmitted through focal adhesion kinase (FAK), it was predicted that FAK would be essential to TGF
-mediated myofibroblast differentiation. To determine whether the FAK signaling pathway is required for myofibroblast differentiation, we used two approaches to decrease FAK in mouse embryo fibroblasts (MEFs): 1) FAK +/+ MEFs, in which FAK protein expression was greatly decreased by short hairpin RNA (shRNA), and 2) FAK -/- MEFs, which lack FAK. In both cases, the majority of cells were myofibroblasts, expressing SM
A in stress fibers even after treatment with FGF/h. Furthermore, both the surface expression of FGFRs and FGF signaling were greatly reduced in FAK-/- MEFs. We conclude that FAK does not contribute to TGF
-dependent myofibroblast differentiation. Instead, FAK was necessary for FGF/h signaling in down-regulating expression of SM
A, which is synonymous with myofibroblast differentiation. FAK activation could contribute to regulating myofibroblast differentiation, thereby ameliorating fibrosis.
This article has been cited by other articles:
![]() |
D. Xing and J. A. Bonanno Effect of cAMP on TGF{beta}1-Induced Corneal Keratocyte-Myofibroblast Transformation Invest. Ophthalmol. Vis. Sci., February 1, 2009; 50(2): 626 - 633. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. Sayers, L. J. Sundberg-Smith, M. Rojas, H. Hayasaka, J. T. Parsons, C. P. Mack, and J. M. Taylor FRNK Expression Promotes Smooth Muscle Cell Maturation During Vascular Development and After Vascular Injury Arterioscler Thromb Vasc Biol, December 1, 2008; 28(12): 2115 - 2122. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Vaahtomeri, E. Ventela, K. Laajanen, P. Katajisto, P.-J. Wipff, B. Hinz, T. Vallenius, M. Tiainen, and T. P. Makela Lkb1 is required for TGF{beta}-mediated myofibroblast differentiation J. Cell Sci., November 1, 2008; 121(21): 3531 - 3540. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Ding, C. L. Gladson, H. Wu, H. Hayasaka, and M. A. Olman Focal Adhesion Kinase (FAK)-related Non-kinase Inhibits Myofibroblast Differentiation through Differential MAPK Activation in a FAK-dependent Manner J. Biol. Chem., October 3, 2008; 283(40): 26839 - 26849. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. F. Walsh, D. R. Ampasala, J. Hatfield, R. Vander Heide, S. Suer, A. K. Rishi, and M. D. Basson Transforming Growth Factor-{beta} Stimulates Intestinal Epithelial Focal Adhesion Kinase Synthesis via Smad- and p38-Dependent Mechanisms Am. J. Pathol., August 1, 2008; 173(2): 385 - 399. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. C. Cushing, P. D. Mariner, J.-T. Liao, E. A. Sims, and K. S. Anseth Fibroblast growth factor represses Smad-mediated myofibroblast activation in aortic valvular interstitial cells FASEB J, June 1, 2008; 22(6): 1769 - 1777. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |