The influence of actin depolymerization induced by Cytochalasin D and mechanical stretch on interleukin-8 expression and JNK phosphorylation levels in human retinal pigment epithelial cells

BMC Ophthalmology

Research Article

Qian Liu¹  Shen Wu¹  JingXue Zhang¹  Meng Gao²  Wu Liu²  Lu Liu³  YanKun Yue³  XinXin Liu⁴  Jing Ji⁵ 

[1] Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China;Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing, China;Department of Ophthalmology, Beijing Fuxing Hospital, Capital Medical University, Beijing, China;Department of Ophthalmology, Kailuan General Hospital, Tangshan, China;Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China;

关键词: Stress;    Mechanical;    Retinal pigment epithelium;    Cytoskeleton;    Cytokines;    Cytochalasin;    JNK Mitogen-activated protein Kinases;   

DOI  :  10.1186/s12886-017-0437-z

 received in 2016-10-28, accepted in 2017-04-04,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundThis study explores the role of actin cytoskeleton depolymerization induced by Cytochalasin D and mechanical stretch on the interleukin-8 (IL-8) expression and c-jun N-terminal kinase (JNK) phosphorylation levels in human retinal pigment epithelial (RPE) cells.MethodsA Flexcell FX-5000 Tension system was used to apply cyclic stretch to cultured human RPE cells (ARPE-19) at 0.33 Hz with 20% elongation for 0 h, 6 h or 24 h. The cells were stretched alone or pre-treated with Cytochalasin D. The redistribution of the actin cytoskeleton was evaluated using phalloidin immunofluorescence staining. The protein expression levels of IL-8 and JNK in the RPE cells were determined via Western blotting.ResultsThe cells in the control groups displayed abundant and uniform phalloidin staining. After exposure to mechanical stretch for 24 h, phalloidin staining revealed an unclear and irregular actin cytoskeleton. In all Cytochalasin D-treated cells, the shrinkage and disruption of the cytoskeletal structure was observed regardless of mechanical stress. The stimulation of the RPE cells with cyclic stretch alone did not induce a significant increase in IL-8 expression and JNK phosphorylation levels, which were similar to those of the control groups. After pre-treatment with Cytochalasin D alone, IL-8 expression and JNK phosphorylation levels were not significantly different at 6 h but were significantly increased by approximately 1.2-fold (1.18 ± 0.05; P<0.01) and 3.0-fold (3.01 ± 0.02; P<0.01) at 24 h, respectively. After the pre-incubation of the RPE cells with Cytochalasin D followed by exposure to cyclic stretch, IL-8 expression and JNK phosphorylation levels increased by approximately 1.3-fold (1.31 ± 0.02; P<0.01) and 1.3-fold (1.31 ± 0.02; P<0.01) at 6 h, respectively, and by 1.7-fold (1.69 ± 0.06; P<0.01) and 3.2-fold (3.21 ± 0.12; P<0.01) at 24 h, respectively.ConclusionsThis study demonstrates that disruption of actin polymerization by cytochalasin D and mechanical stretch upregulates interleukin-8 expression and JNK phosphorylation levels in human RPE cells, which indicates that the integrity of the actin cytoskeleton may play important roles in the pro-inflammatory processes in RPE cells.

【 授权许可】

CC BY   
© The Author(s). 2017