Abstract
Purpose :
The aim of this study was to investigate the effect of platelet-derived growth factor (PDGF)-BB on the proliferation of cells and its possible mechanism in human orbital fibroblasts.
Methods :
Human orbital fibroblasts were obtained from orbital fat from decompression surgery in patients with thyroid-associated ophthalmopathy (TAO). The cells were treated with PDGF-BB and the number of cells number was counted using an ADAM automatic cell counter. The expression of Programmed cell death 4 (PDCD4) was determined by western blotting. The effect of PDCD4 on cell proliferation was evaluated using PDCD4 siRNA treansfected cells. The level of microRNA (miRNA)-21 was measured by quantitative real-time RT-PCR. In addition, the role of miRNA-21 in PDCD4 expression and the proliferation of PDGF-BB-treated cells was assessed using anti-miRNA-21 transfected cells and by treatment with resveratrol, an inhibitor of miRNA-21.
Results :
PDGF-BB was found to enhance cell proliferation, whereas it inhibited PDCD4 expression in human orbital fibroblasts. The down-regulation of PDCD4 by PDCD4 siRNA transfection significantly increased the number of human orbital fibroblasts. In addition, PDGF-BB increased the level of miRNA-21 in human orbital fibroblasts. Transfection with anti-miRNA-21 and treatment with resveratrol partially restored the expression of PDCD4 and led to a reduction in cell number in PDGF-BB treated orbital fibroblasts.
Conclusions :
PDGF-BB enhances proliferation by suppressing PDCD4 expression via the up-regulation of miRNA-21 in human orbital fibroblasts. These results suggest that PDGF-BB stimulates cell proliferation through microRNA-21-mediated PDCD4 down-regulation, subsequently leading to the development of TAO.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.