Elasticity-dependent modulation of TGF-ß responses in human trabecular meshwork cells.
Invest Ophthalmol Vis Sci
; 52(6): 2889-96, 2011 May 02.
Article
em En
| MEDLINE
| ID: mdl-21282571
ABSTRACT
PURPOSE:
To gain further insight into a possible role of biomechanical cues in glaucoma, the authors assessed the influence of extracellular matrix (ECM) elasticity on TGF-ß2-induced changes in trabecular meshwork (TM) cells.METHODS:
Human TM cells derived from donor cornea rings were plated on rigid collagen-coated tissue culture plastic or polyacrylamide gels of different elasticity and treated with vehicle or TGF-ß2. Activation of Smad-2/3, ERK, and AKT signaling and expression of α-SMA and PAI-1 proteins were assessed by Western blot analysis. Subcellular localization of α-SMA was determined by confocal immunofluorescence microscopy. Transcription of collagen-I, -IV, and -VI, α-SMA, PAI-1, fibronectin, fibrillin-1, cochlin, and MGP-1 was studied by RT-qPCR. The contribution of non-Smad signaling pathways to TGF-ß-induced α-SMA and PAI-1 expression was assessed using the small molecule inhibitors U0126 and LY294002.RESULTS:
TGF-ß2-induced activation of Smad-2/3, ERK, and AKT signaling as well as expression of collagen-1, α-SMA, fibulin, and MGP-1 were attenuated with increasing elasticity. In contrast, TGF-ß2-induced collagen-6, fibronectin, PAI-1, and cochlin expression were enhanced on elastic substrates. The MEK-inhibitor U0126 blocked TGF-ß-induced PAI-1 expression, whereas α-SMA expression was enhanced. PI3K inhibition with LY294002 reduced α-SMA expression.CONCLUSIONS:
ECM elasticity modulates TGF-ß-induced signaling and protein expression in human TM cells. Non-Smad signaling contributes to TGF-ß-induced alterations. Increasing ECM elasticity in vitro promotes protein expression patterns reminiscent of patterns reported in primary open-angle glaucoma. Therefore, changes in TM elasticity and mechanical load may have a significant role in primary open-angle glaucoma.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Malha Trabecular
/
Fator de Crescimento Transformador beta
/
Elasticidade
/
Matriz Extracelular
Limite:
Humans
Idioma:
En
Revista:
Invest Ophthalmol Vis Sci
Ano de publicação:
2011
Tipo de documento:
Article