IGF-1 counteracts TGF-beta-mediated enhancement of fibronectin for in vitro human lens epithelial cells.
OBJECTIVE
To determine whether insulin-like growth factor (IGF-1) affects transforming growth factor (TGF-beta)- mediated fibronectin accumulation in human lens epithelial cell line (HLE B-3) cells.


METHODS
HLE B-3 cells were incubated for 24 hours with TGF-beta (10 ng/ mL), IGF-1 (10 ng/mL), or both. Expression of the fibronectin gene was determined using a real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Fibronectin levels were examined using western blot analysis and immunofluorescence staining.


RESULTS
Expression of the fibronectin gene was not different between the TGF-beta/IGF-1 treated group and the TGF-beta treated group (p= 0.116). However, western blot analysis demonstrated decreased fibronectin levels in human lens epithelial cells treated with TGF-beta and IGF-1 compared to those treated with TGF-beta only (p < 0.01). Immunofluorescence staining disclosed inhibition of TGF-beta-induced fibronectin in the presence of IGF-1.


CONCLUSIONS
This study suggests that IGF-1 counteracts TGF-beta-mediated fibronectin accumulation in human lens epithelial cells.
Chung
So-Hyang
SH
Department of Ophthalmology, Inje University College of Medicine, Seoul Paik Hospital, Seoul, Korea.
Jung
Sun-Ah
SA
Cho
Young Jae
YJ
Lee
Joon H
JH
Kim
Eung Kweon
EK
D002460:Cell Line; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005353:Fibronectins / Q000235:genetics* / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D007908:Lens, Crystalline / Q000166:cytology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D005353:Fibronectins; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I