Effect of CLC-2 on the cytoskeleton in human trabecular meshwork cells

Wang,Hong   Wei; Zheng,Ya  Juan

doi:10.3892/mmr.2013.1619

Effect of CLC-2 on the cytoskeleton in human trabecular meshwork cells

Authors:
- Hong Wei Wang
- Ya Juan Zheng
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Affiliations: Department of Ophthalmology, The Second Hospital of Jilin University, Jilin University, Changchun, Jilin 130041, P.R. China
Published online on: August 7, 2013 https://doi.org/10.3892/mmr.2013.1619
Pages: 1099-1105

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Abstract

The chloride channel protein 2 (CLC‑2) is important in maintaining the volume of trabecular meshwork cells by adjusting the outflow of aqueous solutions and maintaining the fluid balance. However, little is known concerning the functions of CLC‑2 in the cytoskeleton, specifically in human trabecular meshwork (HTM) cells. In the present study, two CLC-2 specific siRNAs (siRNA1 and siRNA2) that target CLC-2 mRNA were designed. The siRNAs were transfected into the HTM cells and the results showed that siRNA1 in particular decreased the expression of CLC‑2 by ~45%. Furthermore, an siRNA1‑mediated CLC-2 knockdown significantly reconstructed the actin cytoskeleton and formed cross‑linked actin networks. In addition, the downregulation of the expression of CLC‑2 was associated with increased TGF‑β and Smad2 activities in the HTM cells following 24 h of transfection. In conclusion, these results suggest that CLC‑2 knockdown promotes trabecular meshwork cytoskeletal disorders and may activate the TGF‑β/Smad signaling pathway. Thus, CLC‑2 may be a promising and potential novel therapeutic strategy for combating primary open‑angle glaucoma.

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1	Thinda S, Melson MR and Kuchtey RW: Worsening angle closure glaucoma and choroidal detachments subsequent to closure of a carotid cavernous fistula. BMC Ophthalmol. 12:282012. View Article : Google Scholar
2	Abdelrahman AM and Eltanamly RM: Selective laser trabeculoplasty in Egyptian patients with primary open-angle glaucoma. Middle East Afr J Ophthalmol. 19:299–303. 2012. View Article : Google Scholar : PubMed/NCBI
3	Roh M, Zhang Y, Murakami Y, et al: Etanercept, a widely used inhibitor of tumor necrosis factor-α (TNF-α), prevents retinal ganglion cell loss in a rat model of glaucoma. PLoS One. 7:e400652012.
4	Grieshaber MC, Pienaar A, Olivier J and Stegmann R: Clinical evaluation of the aqueous outflow system in primary open-angle glaucoma for canaloplasty. Invest Ophthalmol Vis Sci. 51:1498–1504. 2010. View Article : Google Scholar : PubMed/NCBI
5	Kotliar KE, Kozlova TV and Lanzl IM: Postoperative aqueous outflow in the human eye after glaucoma filtration surgery: biofluidmechanical considerations. Biomed Tech (Berl). 54:14–22. 2009. View Article : Google Scholar
6	Wang N, Chintala SK, Fini ME and Schuman JS: Activation of a tissue-specific stress response in the aqueous outflow pathway of the eye defines the glaucoma disease phenotype. Nat Med. 7:304–309. 2001. View Article : Google Scholar
7	Bomberger JM, Coutermarsh BA, Barnaby RL and Stanton BA: Arsenic promotes ubiquitinylation and lysosomal degradation of cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in human airway epithelial cells. J Biol Chem. 287:17130–17139. 2012. View Article : Google Scholar
8	Zhu L, Yang H, Zuo W, et al: Differential expression and roles of volume-activated chloride channels in control of growth of normal and cancerous nasopharyngeal epithelial cells. Biochem Pharmacol. 83:324–334. 2012.
9	Comes N, Abad E, Morales M, Borrás T, Gual A and Gasull X: Identification and functional characterization of ClC-2 chloride channels in trabecular meshwork cells. Exp Eye Res. 83:877–889. 2006. View Article : Google Scholar : PubMed/NCBI
10	Földy C, Lee SH, Morgan RJ and Soltesz I: Regulation of fast-spiking basket cell synapses by the chloride channel ClC-2. Nat Neurosci. 13:1047–1049. 2010.PubMed/NCBI
11	Roman RM, Smith RL, Feranchak AP, Clayton GH, Doctor RB and Fitz JG: ClC-2 chloride channels contribute to HTC cell volume homeostasis. Am J Physiol Gastrointest Liver Physiol. 280:G344–G353. 2001.PubMed/NCBI
12	Xiong H, Li C, Garami E, et al: ClC-2 activation modulates regulatory volume decrease. J Membr Biol. 167:215–221. 1999.PubMed/NCBI
13	Britton FC, Hatton WJ, Rossow CF, Duan D, Hume JR and Horowitz B: Molecular distribution of volume-regulated chloride channels (ClC-2 and ClC-3) in cardiac tissues. Am J Physiol Heart Circ Physiol. 279:H2225–H2233. 2000.PubMed/NCBI
14	Thomasy SM, Wood JA, Kass PH, Murphy CJ and Russell P: Substratum stiffness and latrunculin B regulate matrix gene and protein expression in human trabecular meshwork cells. Invest Ophthalmol Vis Sci. 53:952–958. 2012. View Article : Google Scholar : PubMed/NCBI
15	Zhou H, Tang Y, Liang X, Yang X, Yang J, et al: RNAi targeting urokinase-type plasminogen activator receptor inhibits metastasis and progression of oral squamous cell carcinoma in vivo. Int J Cancer. 125:453–462. 2009. View Article : Google Scholar : PubMed/NCBI
16	Peng J, Lei CT, Hu JB and Fan YC: Effects of travoprost on actin cytoskeleton and β-catenin in the human trabecular meshwork cells treated with Dexamethasone. Zhonghua Yan Ke Za Zhi. 47:336–341. 2011.(In Chinese).
17	Sethi A, Mao W, Wordinger RJ and Clark AF: Transforming growth factor-beta induces extracellular matrix protein cross-linking lysyl oxidase (LOX) genes in human trabecular meshwork cells. Invest Ophthalmol Vis Sci. 52:5240–5250. 2011. View Article : Google Scholar
18	Fuchshofer R and Tamm ER: The role of TGF-β in the pathogenesis of primary open-angle glaucoma. Cell Tissue Res. 347:279–290. 2012.
19	Kottler UB, Jünemann AG, Aigner T, Zenkel M, Rummelt C and Schlötzer-Schrehardt U: Comparative effects of TGF-beta and TGF-beta 2 on extracellular matrix production, proliferation, migration, and collagen contraction of human Tenon’s capsule fibroblasts in pseudoexfoliation and primary open-angle glaucoma. Exp Eye Res. 80:121–134. 2005.
20	Cumurcu T, Bulut Y, Demir HD and Yenisehirli G: Aqueous humor erythropoietin levels in patients with primary open-angle glaucoma. J Glaucoma. 16:645–648. 2007. View Article : Google Scholar : PubMed/NCBI
21	Grosheva I, Vittitow JL, Goichberg P, et al: Caldesmon effects on the actin cytoskeleton and cell adhesion in cultured HTM cells. Exp Eye Res. 82:945–958. 2006. View Article : Google Scholar : PubMed/NCBI
22	Li A, Leung CT, Peterson-Yantorno K, Stamer WD, Mitchell CH and Civan MM: Mechanisms of ATP release by human trabecular meshwork cells, the enabling step in purinergic regulation of aqueous humor outflow. J Cell Physiol. 227:172–182. 2012. View Article : Google Scholar : PubMed/NCBI