1
|
Wu X, Liang J, Liu J, Huang Y, Zhang L, Liu X, Guo J, Zhang M, Chen Y, Wang J. Silibinin attenuates TGF-β2-induced fibrogenic changes in human trabecular meshwork cells by targeting JAK2/STAT3 and PI3K/AKT signaling pathways. Exp Eye Res 2024; 244:109939. [PMID: 38789021 DOI: 10.1016/j.exer.2024.109939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 05/13/2024] [Accepted: 05/21/2024] [Indexed: 05/26/2024]
Abstract
Transforming growth factor-β2 (TGF-β2) induced fibrogenic changes in human trabecular meshwork (HTM) cells have been implicated in trabecular meshwork (TM) damage and intraocular pressure (IOP) elevation in primary open-angle glaucoma (POAG) patients. Silibinin (SIL) exhibited anti-fibrotic properties in various organs and tissues. This study aimed to assess the effects of SIL on the TGF-β2-treated HTM cells and to elucidate the underlying mechanisms. Our study found that SIL effectively inhibited HTM cell proliferation, attenuated TGF-β2-induced cell migration, and mitigated TGF-β2-induced reorganization of both actin and vimentin filaments. Moreover, SIL suppressed the expressions of fibronectin (FN), collagen type I alpha 1 chain (COL1A1), and alpha-smooth muscle actin (α-SMA) in the TGF-β2-treated HTM cells. RNA sequencing indicated that SIL interfered with the phosphoinositide 3-kinase (PI3K)/protein kinase B (PKB, also known as AKT) signaling pathway, extracellular matrix (ECM)-receptor interaction, and focal adhesion in the TGF-β2-treated HTM cells. Western blotting demonstrated SIL inhibited the activation of Janus kinase 2 (JAK2)/signal transducers and activators of transcription 3 (STAT3) and the downstream PI3K/AKT signaling pathways induced by TGF-β2, potentially contributing to its inhibitory effects on ECM protein production in the TGF-β2-treated HTM cells. Our study demonstrated the ability of SIL to inhibit TGF-β2-induced fibrogenic changes in HTM cells. SIL could be a potential IOP-lowering agent by reducing the fibrotic changes in the TM tissue of POAG patients, which warrants further investigation through additional animal and clinical studies.
Collapse
Affiliation(s)
- Xueping Wu
- Jinzhou Medical University, Jinzhou, Liaoning, 121001, China; Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Jia Liang
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Jinfeng Liu
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Yijia Huang
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Liyun Zhang
- Department of Ophthalmology, General Hospital of Central Theater Command, Wuhan 430070, P.R. China
| | - Xin Liu
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Junhong Guo
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Min Zhang
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China
| | - Yudong Chen
- The First Dongguan Affiliated Hospital of Guangdong Medical University, Dongguan, Guangdong, 523700, China.
| | - Jiantao Wang
- Shenzhen Eye Hospital, Jinan University, Shenzhen Eye Institute, Shenzhen, Guangdong, 518040, China.
| |
Collapse
|
2
|
Faralli JA, Filla MS, Peters DM. Role of integrins in the development of fibrosis in the trabecular meshwork. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1274797. [PMID: 38983065 PMCID: PMC11182094 DOI: 10.3389/fopht.2023.1274797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 10/09/2023] [Indexed: 07/11/2024]
Abstract
Primary open angle glaucoma (POAG) is a progressive and chronic disease exhibiting many of the features of fibrosis. The extracellular matrix (ECM) in the trabecular meshwork (TM) undergoes extensive remodeling and enhanced rigidity, resembling fibrotic changes. In addition, there are changes associated with myofibroblast activation and cell contractility that further drives tissue fibrosis and stiffening. This review discusses what is known about the integrins in the TM and their involvement in fibrotic processes.
Collapse
Affiliation(s)
- Jennifer A Faralli
- Department of Pathology & Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Mark S Filla
- Department of Pathology & Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| | - Donna M Peters
- Department of Pathology & Laboratory Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
- Department of Ophthalmology & Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI, United States
| |
Collapse
|
3
|
Huang L, Wei Z, Wang X, Lan C, Zhu Y, Ye Q. AZD6738 Decreases Intraocular Pressure and Inhibits Fibrotic Response in Trabecular Meshwork through CHK1/P53 Pathway. Biochem Pharmacol 2022; 206:115340. [DOI: 10.1016/j.bcp.2022.115340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/30/2022] [Accepted: 11/01/2022] [Indexed: 11/07/2022]
|
4
|
Soundararajan A, Ghag SA, Vuda SS, Wang T, Pattabiraman PP. Cathepsin K Regulates Intraocular Pressure by Modulating Extracellular Matrix Remodeling and Actin-Bundling in the Trabecular Meshwork Outflow Pathway. Cells 2021; 10:cells10112864. [PMID: 34831087 PMCID: PMC8616380 DOI: 10.3390/cells10112864] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 10/18/2021] [Accepted: 10/21/2021] [Indexed: 02/02/2023] Open
Abstract
The homeostasis of extracellular matrix (ECM) and actin dynamics in the trabecular meshwork (TM) outflow pathway plays a critical role in intraocular pressure (IOP) regulation. We studied the role of cathepsin K (CTSK), a lysosomal cysteine protease and a potent collagenase, on ECM modulation and actin cytoskeleton rearrangements in the TM outflow pathway and the regulation of IOP. Initially, we found that CTSK was negatively regulated by pathological stressors known to elevate IOP. Further, inactivating CTSK using balicatib, a pharmacological cell-permeable inhibitor of CTSK, resulted in IOP elevation due to increased levels and excessive deposition of ECM-like collagen-1A in the TM outflow pathway. The loss of CTSK activity resulted in actin-bundling via fascin and vinculin reorganization and by inhibiting actin depolymerization via phospho-cofilin. Contrarily, constitutive expression of CTSK decreased ECM and increased actin depolymerization by decreasing phospho-cofilin, negatively regulated the availability of active TGFβ2, and reduced the levels of alpha-smooth muscle actin (αSMA), indicating an antifibrotic action of CTSK. In conclusion, these observations, for the first time, demonstrate the significance of CTSK in IOP regulation by maintaining the ECM homeostasis and actin cytoskeleton-mediated contractile properties of the TM outflow pathway.
Collapse
Affiliation(s)
- Avinash Soundararajan
- Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1160 West Michigan Street, Indianapolis, IN 46202-5209, USA; (A.S.); (S.A.G.); (S.S.V.); (T.W.)
| | - Sachin Anil Ghag
- Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1160 West Michigan Street, Indianapolis, IN 46202-5209, USA; (A.S.); (S.A.G.); (S.S.V.); (T.W.)
| | - Sai Supriya Vuda
- Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1160 West Michigan Street, Indianapolis, IN 46202-5209, USA; (A.S.); (S.A.G.); (S.S.V.); (T.W.)
| | - Ting Wang
- Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1160 West Michigan Street, Indianapolis, IN 46202-5209, USA; (A.S.); (S.A.G.); (S.S.V.); (T.W.)
- Stark Neuroscience Research Institute, 320 West 15th Street, Indianapolis, IN 46202-2266, USA
| | - Padmanabhan Paranji Pattabiraman
- Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, 1160 West Michigan Street, Indianapolis, IN 46202-5209, USA; (A.S.); (S.A.G.); (S.S.V.); (T.W.)
- Stark Neuroscience Research Institute, 320 West 15th Street, Indianapolis, IN 46202-2266, USA
- Correspondence: ; Tel.: +1-317-274-2652
| |
Collapse
|
5
|
Filla MS, Meyer KK, Faralli JA, Peters DM. Overexpression and Activation of αvβ3 Integrin Differentially Affects TGFβ2 Signaling in Human Trabecular Meshwork Cells. Cells 2021; 10:1923. [PMID: 34440692 PMCID: PMC8394542 DOI: 10.3390/cells10081923] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 12/13/2022] Open
Abstract
Studies from our laboratory have suggested that activation of αvβ3 integrin-mediated signaling could contribute to the fibrotic-like changes observed in primary open angle glaucoma (POAG) and glucocorticoid-induced glaucoma. To determine how αvβ3 integrin signaling could be involved in this process, RNA-Seq analysis was used to analyze the transcriptomes of immortalized trabecular meshwork (TM) cell lines overexpressing either a control vector or a wild type (WT) or a constitutively active (CA) αvβ3 integrin. Compared to control cells, hierarchical clustering, PANTHER pathway and protein-protein interaction (PPI) analysis of cells overexpressing WT-αvβ3 integrin or CA-αvβ3 integrin resulted in a significant differential expression of genes encoding for transcription factors, adhesion and cytoskeleton proteins, extracellular matrix (ECM) proteins, cytokines and GTPases. Cells overexpressing a CA-αvβ3 integrin also demonstrated an enrichment for genes encoding proteins found in TGFβ2, Wnt and cadherin signaling pathways all of which have been implicated in POAG pathogenesis. These changes were not observed in cells overexpressing WT-αvβ3 integrin. Our results suggest that activation of αvβ3 integrin signaling in TM cells could have significant impacts on TM function and POAG pathogenesis.
Collapse
Affiliation(s)
- Mark S. Filla
- Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53705, USA; (M.S.F.); (K.K.M.); (J.A.F.)
| | - Kristy K. Meyer
- Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53705, USA; (M.S.F.); (K.K.M.); (J.A.F.)
| | - Jennifer A. Faralli
- Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53705, USA; (M.S.F.); (K.K.M.); (J.A.F.)
| | - Donna M. Peters
- Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53705, USA; (M.S.F.); (K.K.M.); (J.A.F.)
- Ophthalmology & Visual Sciences, University of Wisconsin, Madison, WI 53705, USA
| |
Collapse
|
6
|
Liu Z, Liu X, Cai R, Liu M, Wang R. Identification of a tumor microenvironment-associated prognostic gene signature in bladder cancer by integrated bioinformatic analysis. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2021; 14:551-566. [PMID: 34093942 PMCID: PMC8167492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Bladder cancer is a common malignancy in the urinary system. Stromal and immune cells in tumor microenvironments, including those in the bladder cancer microenvironment, can serve as prognostic markers. However, the complex processes of bladder cancer necessitate large-scale evaluation to better understand the underlying mechanisms and identify biomarkers for diagnosis and treatment. We used the Estimation of STromal and Immune cells in MAlignant Tumors using Expression data algorithm to assess the association between stromal and immune cell-related genes and overall survival of patients with bladder cancer. We also identified and evaluated differentially expressed genes between cancer and non-cancer tissues from The Cancer Genome Atlas. Patients were categorized into different prognosis groups according to their stromal/immune scores based on differential gene expression. In addition, the prognostic value of the differentially expressed genes was assessed in a separate validation cohort using the Gene Expression Omnibus microarray dataset GSE13507, which identified nine genes (TNC, CALD1, PALLD, TAGLN, TGFB1I1, HSPB6, RASL12, CPXM2, and CYR61) associated with overall survival. Multivariate regression analysis showed that three genes (TNC, CALD1, and PALLD) were possible independent prognostic markers for patients with bladder cancer. Multiple gene set enrichment analysis of individual genes showed strong correlations with stromal and immune interactions, indicating that these nine genes may be related to carcinogenesis, invasion, and metastasis of bladder cancer. These findings provide useful insight into the molecular mechanisms of bladder cancer development, and suggest candidate biomarkers for prognosis and treatment.
Collapse
Affiliation(s)
- Zhengchun Liu
- Department of Radiation Oncology, The First Affiliated Hospital of Guangxi Medical University, Radiation Oncology Clinical Medical Research Center of GuangxiNanning 530021, Guangxi, China
- Department of Radiation Oncology, Affiliated Hospital of Guilin Medical UniversityGuilin, Guangxi, China
| | - Xiuli Liu
- Department of Oncology, Affiliated Hospital of Guilin Medical UniversityGuilin, Guangxi, China
| | - Rui Cai
- Department of Radiation Oncology, Affiliated Hospital of Guilin Medical UniversityGuilin, Guangxi, China
| | - Meilian Liu
- Department of Radiation Oncology, Affiliated Hospital of Guilin Medical UniversityGuilin, Guangxi, China
| | - Rensheng Wang
- Department of Radiation Oncology, The First Affiliated Hospital of Guangxi Medical University, Radiation Oncology Clinical Medical Research Center of GuangxiNanning 530021, Guangxi, China
| |
Collapse
|
7
|
Ashok A, Chaudhary S, Kritikos AE, Kang MH, McDonald D, Rhee DJ, Singh N. TGFβ2-Hepcidin Feed-Forward Loop in the Trabecular Meshwork Implicates Iron in Glaucomatous Pathology. Invest Ophthalmol Vis Sci 2020; 61:24. [PMID: 32182331 PMCID: PMC7401420 DOI: 10.1167/iovs.61.3.24] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose Elevated levels of transforming-growth-factor (TGF)-β2 in the trabecular meshwork (TM) and aqueous humor are associated with primary open-angle glaucoma (POAG). The underlying mechanism includes alteration of extracellular matrix homeostasis through Smad-dependent and independent signaling. Smad4, an essential co-Smad, upregulates hepcidin, the master regulator of iron homeostasis. Here, we explored whether TGF-β2 upregulates hepcidin, implicating iron in the pathogenesis of POAG. Methods Primary human TM cells and human and bovine ex vivo anterior segment organ cultures were exposed to bioactive TGF-β2, hepcidin, heparin (a hepcidin antagonist), or N-acetyl carnosine (an antioxidant), and the change in the expression of hepcidin, ferroportin, ferritin, and TGF-β2 was evaluated by semiquantitative RT-PCR, Western blotting, and immunohistochemistry. Increase in reactive oxygen species (ROS) was quantified with dihydroethidium, an ROS-sensitive dye. Results Primary human TM cells and bovine TM tissue synthesize hepcidin locally, which is upregulated by bioactive TGF-β2. Hepcidin downregulates ferroportin, its downstream target, increasing ferritin and iron-catalyzed ROS. This causes reciprocal upregulation of TGF-β2 at the transcriptional and translational levels. Heparin downregulates hepcidin, and reduces TGF-β2-mediated increase in ferritin and ROS. Notably, both heparin and N-acetyl carnosine reduce TGF-β2-mediated reciprocal upregulation of TGF-β2. Conclusions The above observations suggest that TGF-β2 and hepcidin form a self-sustained feed-forward loop through iron-catalyzed ROS. This loop is partially disrupted by a hepcidin antagonist and an anti-oxidant, implicating iron and ROS in TGF-β2-mediated POAG. We propose that modification of currently available hepcidin antagonists for ocular use may prove beneficial for the therapeutic management of TGF-β2-associated POAG.
Collapse
|
8
|
Faralli JA, Filla MS, Peters DM. Effect of αvβ3 Integrin Expression and Activity on Intraocular Pressure. Invest Ophthalmol Vis Sci 2019; 60:1776-1788. [PMID: 31022732 PMCID: PMC6485315 DOI: 10.1167/iovs.18-26038] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Purpose To determine the effects of αvβ3 integrin expression and activation on intraocular pressure (IOP). Methods Cre+/−β3flox/flox mice were treated with topical tamoxifen eye drops for 5 days to activate Cre and excise the β3 integrin gene from the anterior segment. IOP was measured weekly for 11 weeks using rebound tonometry. Mice were then killed and changes in expression of the β3 integrin subunit in Cre+/− β3flox/flox mice were determined using Western blotting analysis and immunofluorescence microscopy. To determine the effect of αvβ3 integrin activation on outflow facility, porcine organ culture anterior segments (POCAS) were perfused with the αvβ3 integrin-activating antibody AP5 or an isotype IgG control for 21 hours. The effect of αvβ3 integrin activation on IOP was measured over 7 days in C57BL/6J mice intracamerally infused with AP5, AP3, IgG, or PBS. Results Deletion of the β3 integrin subunit using the tamoxifen-inducible Cre-loxP system resulted in a decrease in expression of the β3 integrin subunit in the trabecular meshwork and ciliary muscle. Morphologically no gross changes in the anterior segment were detected. Deletion of the β3 integrin subunit resulted in a significantly (P < 0.05) lower IOP in mice within 2 weeks following the tamoxifen treatment and persisted for 11 weeks. Activating the αvβ3 integrin with the AP5 antibody resulted in a significant (P < 0.05) increase in IOP in C57BL/6J mice and a decrease in outflow facility in 42% of the POCAS. Conclusions These studies demonstrate a role for αvβ3 integrin signaling in the regulation of IOP.
Collapse
Affiliation(s)
- Jennifer A Faralli
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States
| | - Mark S Filla
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States
| | - Donna M Peters
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, United States
| |
Collapse
|
9
|
Wang H, Li M, Zhang Z, Xue H, Chen X, Ji Y. Physiological function of myocilin and its role in the pathogenesis of glaucoma in the trabecular meshwork (Review). Int J Mol Med 2018; 43:671-681. [PMID: 30483726 PMCID: PMC6317685 DOI: 10.3892/ijmm.2018.3992] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 11/16/2018] [Indexed: 12/26/2022] Open
Abstract
Myocilin is highly expressed in the trabecular meshwork (TM), which plays an important role in the regulation of intraocular pressure (IOP). Myocilin abnormalities may cause dysfunction of the TM, potentially leading to increased IOP. High IOP is a well‑known primary risk factor for glaucoma. Myocilin mutations are common among glaucoma patients, and they are implicated in juvenile‑onset open‑angle glaucoma (JOAG) and adult‑onset primary open‑angle glaucoma (POAG). Aggregation of aberrant mutant myocilins is closely associated with glaucoma pathogenesis. The aim of the present review was to discuss the recent findings regarding the major physiological functions of myocilin, such as intra‑ and extracellular proteolytic processes. We also aimed to discuss the risk factors associated with myocilin and the development of glaucoma, such as misfolded/mutant myocilin, imbalance of myocilin and extracellular proteins, and instability of mutant myocilin associated with temperature. Finally, we further outlined certain issues that are yet to be resolved, which may represent the basis for future studies on the role of myocilin in glaucoma.
Collapse
Affiliation(s)
- Hongwei Wang
- Department of Ophthalmology, Jingjiang People's Hospital, Jingjiang, Jiangsu 214500, P.R. China
| | - Mingzhe Li
- Department of Ophthalmology, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai 201399, P.R. China
| | - Zhenzhen Zhang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, P.R. China
| | - Haifeng Xue
- Public Health School, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
| | - Xing Chen
- Department of Science and Education, Jingjiang People's Hospital, Jingjiang, Jiangsu 214500, P.R. China
| | - Yong Ji
- Department of General Surgery, Jingjiang People's Hospital, Jingjiang, Jiangsu 214500, P.R. China
| |
Collapse
|
10
|
Xin C, Song S, Johnstone M, Wang N, Wang RK. Quantification of Pulse-Dependent Trabecular Meshwork Motion in Normal Humans Using Phase-Sensitive OCT. Invest Ophthalmol Vis Sci 2018; 59:3675-3681. [PMID: 30029254 PMCID: PMC6054426 DOI: 10.1167/iovs.17-23579] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 05/30/2018] [Indexed: 12/23/2022] Open
Abstract
Purpose The purpose of this study was to characterize the pulsatile motion of trabecular meshwork (TM) in normal subjects and demonstrate its changes in accommodation with phase-sensitive optical coherence tomography (PhS-OCT). Methods A new PhS-OCT laboratory prototype was designed to measure pulsatile TM motion in 13 healthy humans. Two sets of images were captured in 10 subjects, first with best corrective refraction and the other with an additional 3.0 diopters of accommodation. In each image, both maximum velocity (MV) and cumulative displacement (CD) in two selected regions of TM, the internal (IMV and ICD) and external (EMV and ECD) region, were measured. Results For all parameters the intraclass correlation coefficient was >0.75. Neither MV nor CD was significantly different between eyes in individual subjects (PIMV = 0.967, PEMV = 0.391, PICD = 0.603, PECD = 0.482). In 26 eyes, with best corrective refraction, the EMV was higher than the IMV (23.9 ± 9.8 vs. 18.9 ± 8.08 μm/s; P = 0.0001), as was the ECD compared with the ICD (0.340 ±0.125 vs. 0.264 ± 0.111 μm; P = 0.000004). With accommodation, MV and CD significantly increased (PIMV = 0.0003, PEMV = 0.0003, PICD = 0.019, and PECD = 0.007), whereas MV and CD in the external region were still larger than those in the internal area (PEMV vs. IMV = 0.009, PECD vs. ICD = 0.023). Conclusions This study demonstrates the differences in TM motion between the internal and external regions of TM and displays its change with accommodation. The findings and good reproducibility suggest PhS-OCT helps to understand TM function in regulation of IOP, and, with further refinements, it may be useful in clinical management of glaucoma.
Collapse
Affiliation(s)
- Chen Xin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Shaozhen Song
- Department of Bioengineering, University of Washington, Seattle, Washington, United States
| | - Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ruikang K. Wang
- Department of Bioengineering, University of Washington, Seattle, Washington, United States
- Department of Ophthalmology, University of Washington, Seattle, Washington, United States
| |
Collapse
|
11
|
Hernandez H, Millar JC, Curry SM, Clark AF, McDowell CM. BMP and Activin Membrane Bound Inhibitor Regulates the Extracellular Matrix in the Trabecular Meshwork. Invest Ophthalmol Vis Sci 2018; 59:2154-2166. [PMID: 29801150 PMCID: PMC5915111 DOI: 10.1167/iovs.17-23282] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 03/22/2018] [Indexed: 01/18/2023] Open
Abstract
Purpose The trabecular meshwork (TM) has an important role in the regulation of aqueous humor outflow and IOP. Regulation of the extracellular matrix (ECM) by TGFβ2 has been studied extensively. Bone morphogenetic protein (BMP) and activin membrane-bound inhibitor (BAMBI) has been shown to inhibit or modulate TGFβ2 signaling. We investigate the role of TGFβ2 and BAMBI in the regulation of TM ECM and ocular hypertension. Methods Mouse TM (MTM) cells were isolated from B6;129S1-Bambitm1Jian/J flox mice, characterized for TGFβ2 and dexamethasone (DEX)-induced expression of fibronectin, collagen-1, collagen-4, laminin, α-smooth muscle actin, cross-linked actin networks (CLANs) formation, and DEX-induced myocilin (MYOC) expression. MTM cells were transduced with Ad5.GFP to identify transduction efficiency. MTM cells and mouse eyes were transduced with Ad5.Null, Ad5.Cre, Ad5.TGFβ2, or Ad5.TGFβ2 + Ad5.Cre to evaluate the effect on ECM production, IOP, and outflow facility. Results MTM cells express TM markers and respond to DEX and TGFβ2. Ad5.GFP at 100 MOI had the highest transduction efficiency. Bambi knockdown by Ad5.Cre and Ad5.TGFβ2 increased fibronectin, collagen-1, and collagen-4 in TM cells in culture and tissue. Ad5.Cre, Ad5.TGFβ2, and Ad5.TGFβ2 + Ad5.Cre each significantly induced ocular hypertension and lowered aqueous humor outflow facility in transduced eyes. Conclusions We show for the first time to our knowledge that knockdown of Bambi alters ECM expression in cultured cells and mouse TM, reduces outflow facility, and causes ocular hypertension. These data provide a novel insight into the development of glaucomatous TM damage and identify BAMBI as an important regulator of TM ECM and ocular hypertension.
Collapse
Affiliation(s)
- Humberto Hernandez
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - J. Cameron Millar
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Stacy M. Curry
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Abbot F. Clark
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Colleen M. McDowell
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| |
Collapse
|
12
|
石 赟, 周 凡, 罗 洲, 陈 英, 陈 煜, 董 为. [Histological structure of the trabecular meshwork in the eyeball: challenging the traditional concept and preliminary findings in rabbits, rats and mice]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1400-1404. [PMID: 29070474 PMCID: PMC6743950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Indexed: 07/30/2024]
Abstract
OBJECTIVE To verify that the trabecular meshwork (TM) in the wall of the eyeball consists of smooth muscle fibers instead of collagen fibers or endothelial cells. METHODS Eighteen fresh eyeballs from 3 rabbits, 3 SD rats and 3 mice were sectioned along the sagittal plane and sliced after paraffin embedding for HE staining, VG staining, Masson staining, α-SMA immunohistochemistry or CD31 immunohistochemistry. These slices were observed under microscope and the structure of the TM was compared with those of scleral collagen fibers, ciliary muscles and endothelial cells. RESULTS HE staining of the eyeball slices from the 3 animal species resulted in purplish red staining of the TM, which was highly consistent with ciliary muscle fibers. The cell?like structures on the surface of the TM were not clearly outlined, with flat nuclei showing a dark purple staining; these structures did not show obvious boundaries from the TM. Ciliary muscle fibers, which were smooth muscle cells in nature, were aligned in bundles in various directions. The longitudinally sectioned cells were flat and contained purplish cytoplasm and highly flattened nuclei. Scleral collagen fibers were stained dark red with a few fibroblasts sandwiched among them. The long axis of the fibroblasts was in parallel with that of the collagen fibers. The outline of the fibroblast was not clear and the nucleus was flat in dark blue. The vascular endothelial cells presented with different morphologies and contained light purplish cytoplasm and dark nuclei, protruding into the vascular cavity. VG staining of the TM revealed a pale red filamentous structure, and the collagen fibers were stained bright red. Masson staining of the TM showed a reticular structure consisting mainly of dark red fibers intermingled with thin green fibers. Scleral collagen fibers presented with a cord?like green wavy structure. The endothelial cells were green and flat, while the ciliary smooth muscle fibers were purple. In immunohistochemistry for α?SMA, the TM and the ciliary smooth muscle fibers showed a strong positivity in the cytoplasm, while the scleral collagen fibers and vascular endothelial cells showed negative staining; immunohistochemistry for CD31 showed no obvious positive staining in the TM, collagen fibers or ciliary smooth muscle cells from all the animals in spite of slight differences among them. CONCLUSION The TM consists mainly of smooth muscle fibers with a thin layer of peripheral endomysium without endothelial cells.
Collapse
Affiliation(s)
- 赟 石
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 凡琦 周
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 洲才 罗
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 英华 陈
- 南方医科大学 组织学与胚胎学教研室, 广东 广州 510515Department of Histology and Embryology, Southern Medical University, Guangzhou 510515, China
| | - 煜 陈
- 南方医科大学 学实验教学管理中心//国家级医学基础实验教学示范中 心//国家级医学形态学虚拟仿真实验教学中心, 广东 广州 510515Experimental Teaching and Administration Center/State-level Basic Experimental Teaching Demonstration Center/State-level Virtual Simulation Center for Medical Morphology, College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 为人 董
- 南方医科大学 学实验教学管理中心//国家级医学基础实验教学示范中 心//国家级医学形态学虚拟仿真实验教学中心, 广东 广州 510515Experimental Teaching and Administration Center/State-level Basic Experimental Teaching Demonstration Center/State-level Virtual Simulation Center for Medical Morphology, College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| |
Collapse
|
13
|
石 赟, 周 凡, 罗 洲, 陈 英, 陈 煜, 董 为. [Histological structure of the trabecular meshwork in the eyeball: challenging the traditional concept and preliminary findings in rabbits, rats and mice]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:1400-1404. [PMID: 29070474 PMCID: PMC6743950 DOI: 10.3969/j.issn.1673-4254.2017.10.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVE To verify that the trabecular meshwork (TM) in the wall of the eyeball consists of smooth muscle fibers instead of collagen fibers or endothelial cells. METHODS Eighteen fresh eyeballs from 3 rabbits, 3 SD rats and 3 mice were sectioned along the sagittal plane and sliced after paraffin embedding for HE staining, VG staining, Masson staining, α-SMA immunohistochemistry or CD31 immunohistochemistry. These slices were observed under microscope and the structure of the TM was compared with those of scleral collagen fibers, ciliary muscles and endothelial cells. RESULTS HE staining of the eyeball slices from the 3 animal species resulted in purplish red staining of the TM, which was highly consistent with ciliary muscle fibers. The cell?like structures on the surface of the TM were not clearly outlined, with flat nuclei showing a dark purple staining; these structures did not show obvious boundaries from the TM. Ciliary muscle fibers, which were smooth muscle cells in nature, were aligned in bundles in various directions. The longitudinally sectioned cells were flat and contained purplish cytoplasm and highly flattened nuclei. Scleral collagen fibers were stained dark red with a few fibroblasts sandwiched among them. The long axis of the fibroblasts was in parallel with that of the collagen fibers. The outline of the fibroblast was not clear and the nucleus was flat in dark blue. The vascular endothelial cells presented with different morphologies and contained light purplish cytoplasm and dark nuclei, protruding into the vascular cavity. VG staining of the TM revealed a pale red filamentous structure, and the collagen fibers were stained bright red. Masson staining of the TM showed a reticular structure consisting mainly of dark red fibers intermingled with thin green fibers. Scleral collagen fibers presented with a cord?like green wavy structure. The endothelial cells were green and flat, while the ciliary smooth muscle fibers were purple. In immunohistochemistry for α?SMA, the TM and the ciliary smooth muscle fibers showed a strong positivity in the cytoplasm, while the scleral collagen fibers and vascular endothelial cells showed negative staining; immunohistochemistry for CD31 showed no obvious positive staining in the TM, collagen fibers or ciliary smooth muscle cells from all the animals in spite of slight differences among them. CONCLUSION The TM consists mainly of smooth muscle fibers with a thin layer of peripheral endomysium without endothelial cells.
Collapse
Affiliation(s)
- 赟 石
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 凡琦 周
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 洲才 罗
- 南方医科大学 基础医学院, 广东 广州 510515College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 英华 陈
- 南方医科大学 组织学与胚胎学教研室, 广东 广州 510515Department of Histology and Embryology, Southern Medical University, Guangzhou 510515, China
| | - 煜 陈
- 南方医科大学 学实验教学管理中心//国家级医学基础实验教学示范中 心//国家级医学形态学虚拟仿真实验教学中心, 广东 广州 510515Experimental Teaching and Administration Center/State-level Basic Experimental Teaching Demonstration Center/State-level Virtual Simulation Center for Medical Morphology, College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| | - 为人 董
- 南方医科大学 学实验教学管理中心//国家级医学基础实验教学示范中 心//国家级医学形态学虚拟仿真实验教学中心, 广东 广州 510515Experimental Teaching and Administration Center/State-level Basic Experimental Teaching Demonstration Center/State-level Virtual Simulation Center for Medical Morphology, College of Basic Medical Sciences, Southern Medical University, Guangzhou 510515, China
| |
Collapse
|
14
|
Tsukahara R, Umazume K, McDonald K, Kaplan HJ, Tamiya S. Focal adhesion kinase family is involved in matrix contraction by transdifferentiated Müller cells. Exp Eye Res 2017; 164:90-94. [PMID: 28818394 DOI: 10.1016/j.exer.2017.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 07/07/2017] [Accepted: 08/12/2017] [Indexed: 01/01/2023]
Abstract
Transdifferentiated Müller cells that adopt a fibroblastic/myofibroblastic phenotype have been identified in epiretinal membranes (ERMs) in several ocular disorders, and have been implicated to play a role in the formation and/or the contraction of ERMs. We have previously demonstrated that dasatinib, a dual inhibitor of Src-family kinases and Abl kinase, can prevent matrix contraction by transdifferentiated Müller cells. In this study, we examined molecules involved in matrix contraction downstream of primary dasatinib targets. Tyrosine phosphorylation of focal adhesion kinase (FAK) family members FAK and PYK2 was significantly reduced by dasatinib, and select inhibitors for these kinases PF431396, which inhibits both FAK and PYK2, and PF573228, which only inhibits FAK and not PYK2, significantly reduced matrix contraction by transdifferentiated Müller cells. Dasatinib and PF431396 significantly reduced phosphorylation of Hic-5, a protein implicated to play a role in focal adhesions and cell signaling. Our data shows that FAK family members are involved in matrix contraction by transdifferentiated Müller cells, and also implicates that Hic-5 is situated downstream of the FAK family within the signaling pathway.
Collapse
Affiliation(s)
- Rintaro Tsukahara
- Department of Ophthalmology and Visual Sciences, University of Louisville, 301 E Muhammad Ali Blvd., Louisville, KY 40202, USA; Department of Ophthalmology, Tokyo Medical University, Ibaraki Medical Center, 3-20-1 Chuo, Ami, Inashiki-gun, Ibaraki 300-0332, Japan
| | - Kazuhiko Umazume
- Department of Ophthalmology, Tokyo Medical University, 6-7-1 Nishi-Shijuku, Shinjuku, Tokyo 160-0023, Japan
| | - Kevin McDonald
- Department of Ophthalmology and Visual Sciences, University of Louisville, 301 E Muhammad Ali Blvd., Louisville, KY 40202, USA
| | - Henry J Kaplan
- Department of Ophthalmology and Visual Sciences, University of Louisville, 301 E Muhammad Ali Blvd., Louisville, KY 40202, USA
| | - Shigeo Tamiya
- Department of Ophthalmology and Visual Sciences, University of Louisville, 301 E Muhammad Ali Blvd., Louisville, KY 40202, USA.
| |
Collapse
|
15
|
Sheta R, Wang ZQ, Bachvarova M, Plante M, Gregoire J, Renaud MC, Sebastianelli A, Gobeil S, Morin C, Macdonald E, Vanderhyden B, Bachvarov D. Hic-5 regulates epithelial to mesenchymal transition in ovarian cancer cells in a TGFβ1-independent manner. Oncotarget 2017; 8:82506-82530. [PMID: 29137281 PMCID: PMC5669907 DOI: 10.18632/oncotarget.19714] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 06/17/2017] [Indexed: 01/01/2023] Open
Abstract
The molecular basis of epithelial ovarian cancer (EOC) dissemination is still poorly understood. We have previously identified the hydrogen peroxide-inducible clone-5 (Hic-5) gene as hypomethylated in high-grade (HG) serous EOC tumors, compared to normal ovarian tissues. Hic-5 is a focal adhesion scaffold protein and has been primarily studied for its role as a key mediator of TGF-β–induced epithelial-to-mesenchymal transition (EMT) in epithelial cells of both normal and malignant origin; however, its role in EOC has been never investigated. Here we demonstrate that Hic-5 is overexpressed in advanced EOC, and that Hic-5 is upregulated upon TGFβ1 treatment in the EOC cell line with epithelial morphology (A2780s), associated with EMT induction. However, ectopic expression of Hic-5 in A2780s cells induces EMT independently of TGFβ1, accompanied with enhancement of cellular proliferation rate and migratory/invasive capacity and increased resistance to chemotherapeutic drugs. Moreover, Hic-5 knockdown in the EOC cells with mesenchymal morphology (SKOV3) was accompanied by induction of mesenchymal-to-epithelial transition (MET), followed by a reduction of their proliferative, migratory/invasive capacity, and increased drugs sensitivity in vitro, as well as enhanced tumor cell colonization and metastatic growth in vivo. The modulation of Hic-5 expression in EOC cells resulted in altered regulation of numerous EMT-related canonical pathways and was indicative for a possible role of Hic-5 in controlling EMT through a RhoA/ROCK mediated mechanism. To our knowledge, this is the first report examining the role of Hic-5 in EOC, and its role in maintaining the mesenchymal phenotype of EOC cells independently of exogenous TGFβ1 treatment.
Collapse
Affiliation(s)
- Razan Sheta
- Department of Molecular Medicine, Université Laval, Québec, Québec, Canada.,Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada
| | - Zhi-Qiang Wang
- Department of Molecular Medicine, Université Laval, Québec, Québec, Canada.,Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada
| | - Magdalena Bachvarova
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada
| | - Marie Plante
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada.,Department of Obstetrics and Gynecology, Université Laval, Québec, Québec, Canada
| | - Jean Gregoire
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada.,Department of Obstetrics and Gynecology, Université Laval, Québec, Québec, Canada
| | - Marie-Claude Renaud
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada.,Department of Obstetrics and Gynecology, Université Laval, Québec, Québec, Canada
| | - Alexandra Sebastianelli
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada.,Department of Obstetrics and Gynecology, Université Laval, Québec, Québec, Canada
| | - Stephane Gobeil
- Department of Molecular Medicine, Université Laval, Québec, Québec, Canada.,Centre de recherche du CHU de Québec, CHUL, Québec, Québec, Canada
| | - Chantale Morin
- Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada
| | - Elizabeth Macdonald
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Barbara Vanderhyden
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Dimcho Bachvarov
- Department of Molecular Medicine, Université Laval, Québec, Québec, Canada.,Centre de recherche du CHU de Québec, L'Hôtel-Dieu de Québec, Québec, Québec, Canada
| |
Collapse
|
16
|
Cheng J, Liang J, Qi J. Role of nuclear factor (erythroid-derived 2)-like 2 in the age-resistant properties of the glaucoma trabecular meshwork. Exp Ther Med 2017; 14:791-796. [PMID: 28673001 DOI: 10.3892/etm.2017.4543] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 01/26/2017] [Indexed: 12/21/2022] Open
Abstract
Glaucoma is a major cause of irreversible blindness. Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) regulates the expression of numerous antioxidants within cells and is therefore a focus of current ophthalmic research. To determine the roles of Nrf2 in mediating the glaucoma trabecular meshwork (GTM), the present study evaluated the levels of Nrf2 expression in GTM and human trabecular meshwork (HTM) cells by reverse-transcription-quantitative polymerase chain reaction and western blot analysis. It was principally observed that Nrf2 expression was downregulated in GTM cells. In addition, to determine the influence of Nrf2 on the apoptosis and proliferation of GTM and HTM cells, transfection assays and western blotting were performed to evaluate the expression of apoptosis-related proteins. The results of the current study indicated that Nrf2 may promote viability and reduce apoptosis in GTM and HTM cells. Collectively, these data suggest that Nrf2 may be a novel therapeutic target to treat glaucoma.
Collapse
Affiliation(s)
- Jintao Cheng
- Department of Ophthalmology, Yishui Central Hospital, Linyi, Shandong 276400, P.R. China
| | - Jiamei Liang
- Department of Ophthalmology, Yishui Central Hospital, Linyi, Shandong 276400, P.R. China
| | - Jinze Qi
- Department of Ophthalmology, Yishui Central Hospital, Linyi, Shandong 276400, P.R. China
| |
Collapse
|
17
|
Prat C, Belville C, Comptour A, Marceau G, Clairefond G, Chiambaretta F, Sapin V, Blanchon L. Myocilin expression is regulated by retinoic acid in the trabecular meshwork-derived cellular environment. Exp Eye Res 2017; 155:91-98. [PMID: 28153738 DOI: 10.1016/j.exer.2017.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 01/17/2017] [Accepted: 01/25/2017] [Indexed: 12/15/2022]
Abstract
Glaucoma is the leading cause of irreversible blindness and is usually classified as angle closure and open angle glaucoma (OAG). Primary open angle glaucoma represents the most frequent clinical presentation leading to ganglion cell death and optic nerve degeneration as a main consequence of an intraocular pressure' (IOP) increase. The mechanisms of this IOP increase in such pathology remain unclear but one protein called Myocilin could be a part of the puzzle in the trabecular meshwork (TM). Previously described to be transcriptionally regulated by glucocorticoids, the comprehension of the trabecular regulation of Myocilin' expression has only weakly progressed since 15 years. Due to the essential molecular and cellular implications of retinoids' pathway in eye development and physiology, we investigate the potential role of the retinoic acid in such regulation and expression. This study demonstrates that the global retinoids signaling machinery is present in immortalized TM cells and that Myocilin (MYOC) expression is upregulated by retinoic acid alone or combined with a glucocorticoid co-treatment. This regulation by retinoic acid acts through the MYOC promoter which contains a critical cluster of four retinoic acid responsive elements (RAREs), with the RARE-DR2 presenting the strongest effect and binding the RARα/RXRα heterodimer. All together, these results open up new perspectives for the molecular understanding glaucoma pathophysiology and provide further actionable clues on Myocilin gene regulation.
Collapse
Affiliation(s)
- Cécile Prat
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| | - Corinne Belville
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France; GReD, CNRS UMR6293-Clermont Université-INSERM U1103, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| | - Aurélie Comptour
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| | - Geoffroy Marceau
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France; Biochemistry and Molecular Biology Department, CHU Clermont-Ferrand, F-63000 Clermont-Ferrand, France.
| | - Gael Clairefond
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| | - Frédéric Chiambaretta
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France; Biochemistry and Molecular Biology Department, CHU Clermont-Ferrand, F-63000 Clermont-Ferrand, France; CHU Clermont-Ferrand, Ophthalmology Department, F-63000 Clermont-Ferrand, France.
| | - Vincent Sapin
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France; Biochemistry and Molecular Biology Department, CHU Clermont-Ferrand, F-63000 Clermont-Ferrand, France.
| | - Loïc Blanchon
- EA7281 - Retinoids, Reproduction Developmental Diseases, School of Medicine, Clermont Université, Université d'Auvergne, F-63000 Clermont-Ferrand, France.
| |
Collapse
|
18
|
The role of integrins in glaucoma. Exp Eye Res 2016; 158:124-136. [PMID: 27185161 DOI: 10.1016/j.exer.2016.05.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 05/06/2016] [Accepted: 05/10/2016] [Indexed: 01/04/2023]
Abstract
Integrins are a family of heterodimeric transmembrane receptors that mediate adhesion to the extracellular matrix (ECM). In addition to their role as adhesion receptors, integrins can act as ''bidirectional signal transducers'' that coordinate a large number of cellular activities in response to the extracellular environment and intracellular signaling events. This bidirectional signaling helps maintain tissue homeostasis. Dysregulated bidirectional signaling, however, could trigger the propagation of feedback loops that can lead to the establishment of a disease state such as glaucoma. Here we discuss the role of integrins and bidirectional signaling as they relate to the glaucomatous phenotype with special emphasis on the αvβ3 integrin. We present evidence that this particular integrin may have a significant impact on the pathogenesis of glaucoma.
Collapse
|
19
|
Varney SD, Betts CB, Zheng R, Wu L, Hinz B, Zhou J, Van De Water L. Hic-5 is required for myofibroblast differentiation by regulating mechanically dependent MRTF-A nuclear accumulation. J Cell Sci 2016; 129:774-87. [PMID: 26759173 DOI: 10.1242/jcs.170589] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 01/04/2016] [Indexed: 01/21/2023] Open
Abstract
How mechanical cues from the extracellular environment are translated biochemically to modulate the effects of TGF-β on myofibroblast differentiation remains a crucial area of investigation. We report here that the focal adhesion protein, Hic-5 (also known as TGFB1I1), is required for the mechanically dependent generation of stress fibers in response to TGF-β. Successful generation of stress fibers promotes the nuclear localization of the transcriptional co-factor MRTF-A (also known as MKL1), and this correlates with the mechanically dependent induction of α smooth muscle actin (α-SMA) and Hic-5 in response to TGF-β. As a consequence of regulating stress fiber assembly, Hic-5 is required for the nuclear accumulation of MRTF-A and the induction of α-SMA as well as cellular contractility, suggesting a crucial role for Hic-5 in myofibroblast differentiation. Indeed, the expression of Hic-5 was transient in acute wounds and persistent in pathogenic scars, and Hic-5 colocalized with α-SMA expression in vivo. Taken together, these data suggest that a mechanically dependent feed-forward loop, elaborated by the reciprocal regulation of MRTF-A localization by Hic-5 and Hic-5 expression by MRTF-A, plays a crucial role in myofibroblast differentiation in response to TGF-β.
Collapse
Affiliation(s)
- Scott D Varney
- Center for Cell Biology and Cancer Research (MC-165), Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
| | - Courtney B Betts
- Center for Cell Biology and Cancer Research (MC-165), Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
| | - Rui Zheng
- Center for Cell Biology and Cancer Research (MC-165), Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
| | - Lei Wu
- Center for Cell Biology and Cancer Research (MC-165), Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
| | - Boris Hinz
- Laboratory of Tissue Repair and Regeneration, Matrix Dynamics Group, Faculty of Dentistry, University of Toronto, 150 College Street, FitzGerald Building, Room 234, Toronto, Ontario, Canada M5S 3E2
| | - Jiliang Zhou
- Department of Pharmacology & Toxicology, Medical College of Georgia, Georgia Regents University, CB-3628, 1459 Laney Walker Boulevard, Augusta, GA 30912, USA
| | - Livingston Van De Water
- Center for Cell Biology and Cancer Research (MC-165), Albany Medical College, 47 New Scotland Avenue, Albany, NY 12208, USA
| |
Collapse
|