4 353

Cited 10 times in

Lysophosphatidic acid activates TGFBIp expression in human corneal fibroblasts through a TGF-β1-dependent pathway.

 Eun Su Jeon  ;  Jae Ho Kim  ;  Hyunmi Ryu  ;  Eung Kweon Kim 
 CELLULAR SIGNALLING, Vol.24(6) : 1241-1250, 2012 
Journal Title
Issue Date
Lysophosphatidic acid ; TGFBIp ; TGF-β ; Corneal dystrophy
Granular corneal dystrophy type 2 (GCD2) is an autosomal dominant disease caused by a R124H point mutation in the transforming growth factor-β-induced gene (TGFBI). However, the cellular role of TGFBI and the regulatory mechanisms underlying corneal dystrophy pathogenesis are still poorly understood. Lysophosphatidic acid (LPA) refers to a small bioactive phospholipid mediator produced in various cell types, and binds G protein-coupled receptors to enhance numerous biological responses, including cell growth, inflammation, and differentiation. LPA levels are elevated in injured cornea and LPA is involved in proliferation and wound healing of cornea epithelial cells. Accumulating evidence has indicated a crucial role for LPA-induced expression of TGFBI protein (TGFBIp) through secretion of transforming growth factor-beta1 (TGF-β1). In the current study, we demonstrate that LPA induces TGFBIp expression in corneal fibroblasts derived from normal or GCD2 patients. LPA-induced TGFBIp expression was completely inhibited upon pretreatment with the LPA(1/3) receptor antagonists, VPC32183 and Ki16425, as well as by silencing LPA(1) receptor expression with small hairpin RNA (shRNA) in corneal fibroblasts. LPA induced secretion of TGF-β1 in corneal fibroblasts, and pretreatment with the TGF-β type I receptor kinase inhibitor SB431542 or an anti-TGF-β1 neutralizing antibody also inhibited LPA-induced TGFBIp expression. Furthermore, we show that LPA requires Smad2/3 proteins for the induction of TGFBIp expression. LPA elicited phosphorylation of Smad2/3, and Smad3 specific inhibitor SIS3 or siRNA-mediated depletion of endogenous Smad2/3 abrogates LPA-induced TGFBIp expression. Finally, we demonstrate that LPA-mediated TGFBIp induction requires JNK activation, but not ERK signaling pathways. These results suggest that LPA stimulates TGFBIp expression through JNK-dependent activation of autocrine TGF-β1 signaling pathways and provide important information for understanding the role of phospholipids involved in cornea related diseases.
Full Text
Appears in Collections:
5. Research Institutes (연구소) > Corneal Dystrophy Research Institute (각막이상증연구소) > 1. Journal Papers
1. College of Medicine (의과대학) > Yonsei Biomedical Research Center (연세의생명연구원) > 1. Journal Papers
1. College of Medicine (의과대학) > Dept. of Ophthalmology (안과학교실) > 1. Journal Papers
Yonsei Authors
Kim, Eung Kweon(김응권) ORCID logo https://orcid.org/0000-0002-1453-8042
Ryu, Hyun Mi(류현미)
Jeon, Eun Su(전은수)
사서에게 알리기


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.