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Graefe's Archive for Clinical and Experimental Ophthalmology

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01-06-2015 | Basic Science

Combined silencing of TGF-β2 and Snail genes inhibit epithelial-mesenchymal transition of retinal pigment epithelial cells under hypoxia

Authors: Zhuolei Feng, Ruishu Li, Huanqi Shi, Wenjiao Bi, Wenwen Hou, Xiaomei Zhang

Published in: Graefe's Archive for Clinical and Experimental Ophthalmology | Issue 6/2015

Abstract

Background

The formation of scar-like fibrous tissue in age-related macular degeneration (AMD) is associated with hypoxia. Under hypoxia, retinal pigment epithelial (RPE) cells can secret more transforming growth factor-β₂ (TGF-β₂), which is determined to induce epithelial-mesenchymal transition (EMT) at certain concentrations. Whether hypoxia can induce EMT by stimulating RPE cell line secrets TGF-β₂ or not remains unknown. To gain a better understanding of the signaling mechanisms of fibrosis in AMD under hypoxic conditions, we investigated EMT in retinal pigment epithelial (RPE) cells and the effect of TGF-β₂ and Snail in this process.

Methods

Human RPE cell line (ARPE-19) was incubated with 5 % O₂ for different periods of time. The expression of N-cadherin, α-smooth muscle actin (α-SMA), TGF-β₂ , and Snail were determined by Western blot and real-time PCR. Cell proliferation was assessed by CCK8 kit. RNA interference was used for multi-gene silencing of TGF-β₂ and Snail genes.

Results

N-cadherin was decreased and mesenchymal cell marker α-SMA was increased after the ARPE-19 cell line was incubated with 5 % O₂. Meanwhile, the proliferation capability of the cell line was increased. TGF-β₂ and Snail expression were increased in a time-dependent manner under hypoxia. After multi-silencing TGF-β₂ and Snail genes, N-cadherin was increased and α-SMA was reduced. Meanwhile, the proliferation of the cell line was suppressed.

Conclusions

Under hypoxic conditions, RPE cells undergo EMT. Endogenic TGF-β₂ and Snail are involved in this process. Furthermore, knockdown of both TGF-β₂ and Snail inhibited EMT to a greater extent than knockdown of either gene individually.

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Title: Combined silencing of TGF-β2 and Snail genes inhibit epithelial-mesenchymal transition of retinal pigment epithelial cells under hypoxia
Authors: Zhuolei Feng
Ruishu Li
Huanqi Shi
Wenjiao Bi
Wenwen Hou
Xiaomei Zhang
Publication date: 01-06-2015
Publisher: Springer Berlin Heidelberg
Published in: Graefe's Archive for Clinical and Experimental Ophthalmology / Issue 6/2015
Print ISSN: 0721-832X
Electronic ISSN: 1435-702X
DOI: https://doi.org/10.1007/s00417-014-2922-x

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Springer Medicine

Combined silencing of TGF-β2 and Snail genes inhibit epithelial-mesenchymal transition of retinal pigment epithelial cells under hypoxia

Abstract

Background

Methods

Results

Conclusions

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Results

Conclusions

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