Effects of transforming growth factor-β2 on myocilin expression and secretion in human primary cultured trabecular meshwork cells

• Published in: International journal of clinical and experimental pathology Vol. 7; no. 8; pp. 4827 - 4836
• Main Authors: Wu, Yuyu, Chen, Wanzhu, Guo, Maosheng, He, Qin, Hu, Yan
• Format: Journal Article
• Language: English
• Published: United States e-Century Publishing Corporation 2014
• Subjects: Adult; Blotting, Western; Cells, Cultured; Cytoskeletal Proteins - biosynthesis; Cytoskeletal Proteins - secretion; Enzyme-Linked Immunosorbent Assay; Eye Proteins - biosynthesis; Eye Proteins - secretion; Female; Glycoproteins - biosynthesis; Glycoproteins - secretion; Humans; Male; Original; Reverse Transcriptase Polymerase Chain Reaction; Trabecular Meshwork - metabolism; Transforming Growth Factor beta2 - metabolism; myocilin; glaucoma; trabecular meshwork cells; Primary cell culture; transforming growth factor-beta 2
• ISSN: 1936-2625; 1936-2625

High intraocular pressure (IOP) is a risk factor for primary open-angle glaucoma (POAG). The trabecular meshwork (TM), a reticular tissue in the outflow passage of the aqueous humor (AH), is a major contributor to intraocular outflow resistance. High levels of myocilin (MYOC), which is expressed in the TM, are associated with high IOP. Furthermore, transforming growth factor-β2 (TGF-β2) concentrations in human AH are significantly elevated in POAG patients. This study was designed to investigate the effects of TGF-β2 on MYOC expression and secretion in human primary cultured TM cells. Primary cultured human TM cells were treated with 0 (control group), 1, 10, and 100 ng/mL TGF-β2 for 12, 24, or 48 h. MYOC mRNA and protein expressions in TM cells and protein secretion in conditioned media were analyzed by semi-quantitative RT-PCR, Western blotting, and enzyme-linked immunosorbent assays (ELISA), respectively. TM cells treated with 1, 10, and, 100 ng/mL TGF-β2 for 48 h showed higher MYOC mRNA and protein expressions than those in the control group (0 ng/mL TGF-β2) (all P < 0.05). Treatment with TGF-β2 for 48 h also induced MYOC secretion in conditioned media in a dose-dependent manner (0 ng/mL: 7.107±1.163 pg/ml; 1 ng/mL: 7.879±1.894 pg/ml; 10 ng/mL: 8.063±1.181 pg/ml; 100 ng/mL: 8.902±0.699 pg/ml; all P < 0.05). In Conclusion, TGF-β2 induced MYOC expression and secretion in human primary cultured TM cells. Further investigations are required to confirm the involvement of these two factors in POAG pathogenesis.