1
|
Graybeal K, Sanchez L, Zhang C, Stiles L, Zheng JJ. Characterizing the metabolic profile of dexamethasone treated human trabecular meshwork cells. Exp Eye Res 2021; 214:108888. [PMID: 34896106 DOI: 10.1016/j.exer.2021.108888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/29/2021] [Accepted: 12/03/2021] [Indexed: 11/19/2022]
Abstract
The trabecular meshwork (TM) is the leading site of aqueous humor outflow in the eye and plays a critical role in maintaining normal intraocular pressure. When the TM fails to maintain normal intraocular pressure, glaucoma may develop. Mitochondrial damage has previously been found in glaucomatous TM cells; however, the precise metabolic activity of glaucomatous TM cells has yet to be quantitatively assessed. Using dexamethasone (Dex) treated primary human TM cells to model glaucomatous TM cells, we measure the respiratory and glycolytic activity of Dex-treated TM cells with an extracellular flux assay. We found that Dex-treated TM cells had quantifiably altered metabolic profiles, including increased spare respiratory capacity and ATP production rate from oxidative phosphorylation. Therefore, we propose that reversing or preventing these metabolic changes may represent an avenue for future research.
Collapse
Affiliation(s)
- Kimberly Graybeal
- Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, The Molecular Biology Institute at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Luis Sanchez
- Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, The Molecular Biology Institute at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Chi Zhang
- Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, The Molecular Biology Institute at the University of California, Los Angeles, Los Angeles, CA, USA
| | - Linsey Stiles
- Department of Medicine, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Endocrinology, Los Angeles, CA, USA
| | - Jie J Zheng
- Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, The Molecular Biology Institute at the University of California, Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
2
|
Watanabe M, Ida Y, Furuhashi M, Tsugeno Y, Hikage F, Ohguro H. Pan-ROCK and ROCK2 Inhibitors Affect Dexamethasone-Treated 2D- and 3D-Cultured Human Trabecular Meshwork (HTM) Cells in Opposite Manners. Molecules 2021; 26:molecules26216382. [PMID: 34770791 PMCID: PMC8587022 DOI: 10.3390/molecules26216382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 10/07/2021] [Accepted: 10/18/2021] [Indexed: 01/21/2023] Open
Abstract
Effects of a pan-ROCK-inhibitor, ripasudil (Rip), and a ROCK2 inhibitor, KD025 on dexamethasone (DEX)-treated human trabecular meshwork (HTM) cells as a model of steroid-induced glaucoma were investigated. In the presence of Rip or KD025, DEX-treated HTM cells were subjected to permeability analysis of 2D monolayer by transendothelial electrical resistance (TEER) and FITC–dextran permeability, physical properties, size and stiffness analysis (3D), and qPCR of extracellular matrix (ECM), and their modulators. DEX resulted in a significant increase in the permeability, as well as a large and stiff 3D spheroid, and those effects were inhibited by Rip. In contrast, KD025 exerted opposite effects on the physical properties (down-sizing and softening). Furthermore, DEX induced several changes of gene expressions of ECM and their modulators were also modulated differently by Rip and KD025. The present findings indicate that Rip and KD025 induced opposite effects toward 2D and 3D cell cultures of DEX-treated HTM cells.
Collapse
Affiliation(s)
- Megumi Watanabe
- Departments of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo 060-8556, Japan; (M.W.); (Y.I.); (Y.T.); (F.H.)
| | - Yosuke Ida
- Departments of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo 060-8556, Japan; (M.W.); (Y.I.); (Y.T.); (F.H.)
| | - Masato Furuhashi
- Departments of Cardiovascular, Renal and Metabolic Medicine, Sapporo Medical University, Sapporo 060-8556, Japan;
| | - Yuri Tsugeno
- Departments of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo 060-8556, Japan; (M.W.); (Y.I.); (Y.T.); (F.H.)
| | - Fumihito Hikage
- Departments of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo 060-8556, Japan; (M.W.); (Y.I.); (Y.T.); (F.H.)
| | - Hiroshi Ohguro
- Departments of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo 060-8556, Japan; (M.W.); (Y.I.); (Y.T.); (F.H.)
- Correspondence: ; Tel.: +81-611-2111
| |
Collapse
|
3
|
Thomson BR, Liu P, Onay T, Du J, Tompson SW, Misener S, Purohit RR, Young TL, Jin J, Quaggin SE. Cellular crosstalk regulates the aqueous humor outflow pathway and provides new targets for glaucoma therapies. Nat Commun 2021; 12:6072. [PMID: 34663817 PMCID: PMC8523664 DOI: 10.1038/s41467-021-26346-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Accepted: 09/30/2021] [Indexed: 11/09/2022] Open
Abstract
Primary congenital glaucoma (PCG) is a severe disease characterized by developmental defects in the trabecular meshwork (TM) and Schlemm's canal (SC), comprising the conventional aqueous humor outflow pathway of the eye. Recently, heterozygous loss of function variants in TEK and ANGPT1 or compound variants in TEK/SVEP1 were identified in children with PCG. Moreover, common variants in ANGPT1and SVEP1 have been identified as risk alleles for primary open angle glaucoma (POAG) in GWAS studies. Here, we show tissue-specific deletion of Angpt1 or Svep1 from the TM causes PCG in mice with severe defects in the adjacent SC. Single-cell transcriptomic analysis of normal and glaucomatous Angpt1 deficient eyes allowed us to identify distinct TM and SC cell populations and discover additional TM-SC signaling pathways. Furthermore, confirming the importance of angiopoietin signaling in SC, delivery of a recombinant ANGPT1-mimetic promotes developmental SC expansion in healthy and Angpt1 deficient eyes, blunts intraocular pressure (IOP) elevation and RGC loss in a mouse model of PCG and lowers IOP in healthy adult mice. Our data highlight the central role of ANGPT1-TEK signaling and TM-SC crosstalk in IOP homeostasis and provide new candidates for SC-targeted glaucoma therapy.
Collapse
Affiliation(s)
- Benjamin R Thomson
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Pan Liu
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Tuncer Onay
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Jing Du
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Stuart W Tompson
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Sol Misener
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Raj R Purohit
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Terri L Young
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Jing Jin
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA
| | - Susan E Quaggin
- Division of Nephrology and Hypertension, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
- The Feinberg Cardiovascular and Renal Research Institute, Chicago, IL, USA.
| |
Collapse
|
4
|
Fan X, Bilir EK, Kingston OA, Oldershaw RA, Kearns VR, Willoughby CE, Sheridan CM. Replacement of the Trabecular Meshwork Cells-A Way Ahead in IOP Control? Biomolecules 2021; 11:biom11091371. [PMID: 34572584 PMCID: PMC8464777 DOI: 10.3390/biom11091371] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/09/2021] [Accepted: 09/13/2021] [Indexed: 12/11/2022] Open
Abstract
Glaucoma is one of the leading causes of vision loss worldwide, characterised with irreversible optic nerve damage and progressive vision loss. Primary open-angle glaucoma (POAG) is a subset of glaucoma, characterised by normal anterior chamber angle and raised intraocular pressure (IOP). Reducing IOP is the main modifiable factor in the treatment of POAG, and the trabecular meshwork (TM) is the primary site of aqueous humour outflow (AH) and the resistance to outflow. The structure and the composition of the TM are key to its function in regulating AH outflow. Dysfunction and loss of the TM cells found in the natural ageing process and more so in POAG can cause abnormal extracellular matrix (ECM) accumulation, increased TM stiffness, and increased IOP. Therefore, repair or regeneration of TM's structure and function is considered as a potential treatment for POAG. Cell transplantation is an attractive option to repopulate the TM cells in POAG, but to develop a cell replacement approach, various challenges are still to be addressed. The choice of cell replacement covers autologous or allogenic approaches, which led to investigations into TM progenitor cells, induced pluripotent stem cells (iPSCs), and mesenchymal stem cells (MSCs) as potential stem cell source candidates. However, the potential plasticity and the lack of definitive cell markers for the progenitor and the TM cell population compound the biological challenge. Morphological and differential gene expression of TM cells located within different regions of the TM may give rise to different cell replacement or regenerative approaches. As such, this review describes the different approaches taken to date investigating different cell sources and their differing cell isolation and differentiation methodologies. In addition, we highlighted how these approaches were evaluated in different animal and ex vivo model systems and the potential of these methods in future POAG treatment.
Collapse
Affiliation(s)
- Xiaochen Fan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Emine K. Bilir
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Olivia A. Kingston
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Rachel A. Oldershaw
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK;
| | - Victoria R. Kearns
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
| | - Colin E. Willoughby
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
- Genomic Medicine, Biomedical Sciences Research Institute, Ulster University, Coleraine BT52 1SA, UK
- Correspondence: (C.E.W.); (C.M.S.); Tel.: +44-(28)-701-2338 (C.E.W.); +44-(151)-794-9031 (C.M.S.)
| | - Carl M. Sheridan
- Department of Eye and Vision Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L69 3BX, UK; (X.F.); (E.K.B.); (O.A.K.); (V.R.K.)
- Correspondence: (C.E.W.); (C.M.S.); Tel.: +44-(28)-701-2338 (C.E.W.); +44-(151)-794-9031 (C.M.S.)
| |
Collapse
|
5
|
Lee J, Choi JA, Ju HH, Kim JE, Paik SY, Rao PV. Role of MCP-1 and IL-8 in viral anterior uveitis, and contractility and fibrogenic activity of trabecular meshwork cells. Sci Rep 2021; 11:14950. [PMID: 34294770 PMCID: PMC8298573 DOI: 10.1038/s41598-021-94391-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 07/08/2021] [Indexed: 12/02/2022] Open
Abstract
The inflammatory chemokines, monocyte chemoattractant protein (MCP)-1 and IL-8, are produced by normal trabecular meshwork cells (TM) and elevated in the aqueous humor of primary open angle glaucoma (POAG) and hypertensive anterior uveitis associated with viral infection. However, their role in TM cells and aqueous humor outflow remains unclear. Here, we explored the possible involvement of MCP-1 and IL-8 in the physiology of TM cells in the context of aqueous outflow, and the viral anterior uveitis. We found that the stimulation of human TM cells with MCP-1 and IL-8 induced significant increase in the formation of actin stress fibers and focal adhesions, myosin light chain phosphorylation, and the contraction of TM cells. MCP-1 and IL-8 also demonstrated elevation of extracellular matrix proteins, and the migration of TM cells. When TM cells were infected with HSV-1 and CMV virus, there was a significant increase in cytoskeletal contraction and Rho-GTPase activation. Viral infection of TM cells revealed significantly increased expression of MCP-1 and IL-8. Taken together, these results indicate that MCP-1 and IL-8 induce TM cell contractibility, fibrogenic activity, and plasticity, which are presumed to increase resistance to aqueous outflow in viral anterior uveitis and POAG.
Collapse
Affiliation(s)
- Jiyoung Lee
- Department of Ophthalmology and Visual Science, College of Medicine, St. Vincent's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 137-701, Republic of Korea
| | - Jin A Choi
- Department of Ophthalmology and Visual Science, College of Medicine, St. Vincent's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 137-701, Republic of Korea.
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA.
| | - Hyun-Hee Ju
- Department of Ophthalmology and Visual Science, College of Medicine, St. Vincent's Hospital, The Catholic University of Korea, Banpo-daero 222, Seocho-gu, Seoul, 137-701, Republic of Korea
| | - Ju-Eun Kim
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Soon-Young Paik
- Department of Microbiology, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
6
|
Li YC, Zheng J, Wang XZ, Wang X, Liu WJ, Gao JL. Mesenchymal stem cell-derived exosomes protect trabecular meshwork from oxidative stress. Sci Rep 2021; 11:14863. [PMID: 34290351 PMCID: PMC8295363 DOI: 10.1038/s41598-021-94365-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/09/2021] [Indexed: 12/22/2022] Open
Abstract
This study aims to investigate the beneficial effects of exosomes derived from bone marrow mesenchymal stem cells (BMSCs) on trabecular meshwork cells under oxidative stress and predict candidate genes associated with this process. Trabecular meshwork cells were pretreated with BMSC-derived exosomes for 24 h, and exposed to 0.1 mM H2O2 for 6 h. Survival rate of trabecular meshwork cells was measured with CCK-8 assay. Production of intracellular reactive oxygen species (iROS) was measured using a flow cytometer. RT-PCR and ELISA were used to detect mRNA and protein levels of inflammatory cytokines and matrix metalloproteinases (MMPs). Sequencing of RNA and miRNA for trabecular meshwork cells from Exo and control groups was performed on BGISEQ500 platform. Phenotypically, pretreatment of BMSC-derived exosomes improves survival rate of trabecular meshwork cells exposed to H2O2, reduces production of iROS, and inhibits expression of inflammatory cytokines, whereas increases expression of MMPs. There were 23 miRNAs, 307 lncRNAs, and 367 mRNAs differentially expressed between Exo and control groups. Exosomes derived from BMSCs may protect trabecular meshwork cells from oxidative stress. Candidate genes responsible for beneficial effects, such as DIO2 and HMOX1, were predicted.
Collapse
Affiliation(s)
- Ying-Chao Li
- Department of Ophthalmology, Liaocheng People's Hospital, Cheeloo College of Medicine, Shandong University, Liaocheng, 252000, Shandong, China
- Department of Ophthalmology, Taian City Central Hospital, Taian, 271000, Shandong, China
| | - Juan Zheng
- Joint Laboratory for Translational Medicine Research, Beijing Institute of Genomics, Chinese Academy of Sciences & Liaocheng People's Hospital, Liaocheng, 252000, Shandong, China
| | - Xi-Zi Wang
- Joint Laboratory for Translational Medicine Research, Beijing Institute of Genomics, Chinese Academy of Sciences & Liaocheng People's Hospital, Liaocheng, 252000, Shandong, China
| | - Xin Wang
- Department of Ophthalmology, Liaocheng People's Hospital, Liaocheng, 252000, Shandong, China
| | - Wen-Jing Liu
- Department of Ophthalmology, Taian City Central Hospital, Taian, 271000, Shandong, China
| | - Jian-Lu Gao
- Department of Ophthalmology, Liaocheng People's Hospital, Cheeloo College of Medicine, Shandong University, Liaocheng, 252000, Shandong, China.
- Department of Ophthalmology, Liaocheng People's Hospital, Liaocheng, 252000, Shandong, China.
| |
Collapse
|
7
|
Lerner N, Chen I, Schreiber-Avissar S, Beit-Yannai E. Extracellular Vesicles Mediate Anti-Oxidative Response-In Vitro Study in the Ocular Drainage System. Int J Mol Sci 2020; 21:ijms21176105. [PMID: 32854215 PMCID: PMC7504638 DOI: 10.3390/ijms21176105] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 08/17/2020] [Accepted: 08/21/2020] [Indexed: 12/12/2022] Open
Abstract
The importance of extracellular vesicles (EVs) as signaling mediators has been emphasized for several pathways with only limited data regarding their role as protective messages during oxidative stress (OS). The ocular drainage system is unique by being continuously exposed to OS and having a one-way flow of the aqueous humor carrying EVs taking role in glaucoma disease. Here, we aimed to examine the ability of EVs derived from the non-pigmented ciliary epithelium (NPCE)—the aqueous humor producing cells exposed to OS—to deliver protecting messages to the trabecular meshwork (TM)—the aqueous humor draining cells—a process with significance to the pathophysiology of glaucoma disease. EVs extracted from media of NPCE cells exposed to non-lethal OS and their unstressed control were incubated with TM cells. The effects of EVs derived from oxidative stressed cells on the activation of the nuclear factor erythroid 2-related factor 2-Kelch-like ECH-associated protein 1 (Nrf2-Keap1), a major OS pathway, and of the Wnt pathway, known for its role in primary open-angle glaucoma, were evaluated. EVs derived from oxidized NPCE cells significantly protected TM cells from direct OS. The TM cells uptake of EVs from oxidized NPCE and their cytosolic Nrf2 levels were significantly higher at 8 h post-exposure. EVs derived from oxidized NPCE cells significantly attenuated Wnt protein expression in TM cells and activated major antioxidant genes as measured by qRT-PCR. TM cells exposed to EVs derived from oxidized NPCE cells exhibited significantly lower OS and higher super oxide dismutase and catalase activity. Finally, we were able to show that carbonylated proteins and products of oxidized protein are presented in significantly higher levels in EVs derived from oxidized NPCE cells, supporting their suggested role in the signaling process. We hypothesize that these findings may have implications beyond understanding the pathophysiology of glaucoma disease and that transmitting signals that activate the antioxidant system in target cells represent a broad response common to many tissues communication.
Collapse
|
8
|
Faralli JA, Filla MS, McDowell CM, Peters DM. Disruption of fibronectin fibrillogenesis affects intraocular pressure (IOP) in BALB/cJ mice. PLoS One 2020; 15:e0237932. [PMID: 32822410 PMCID: PMC7444551 DOI: 10.1371/journal.pone.0237932] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 08/05/2020] [Indexed: 12/31/2022] Open
Abstract
Increased deposition of fibronectin fibrils containing EDA+fibronectin by TGFβ2 is thought to be involved in the reduction of aqueous humor outflow across the trabecular meshwork (TM) of the eye and the elevation in intraocular pressure (IOP) observed in primary open angle glaucoma (POAG). Using a fibronectin-binding peptide called FUD that can disrupt fibronectin fibrillogenesis, we examined if disrupting fibronectin fibrillogenesis would affect IOP in the TGFβ2 BALB/cJ mouse model of ocular hypertension. BALB/cJ mice that had been intravitreally injected with an adenovirus (Ad5) expressing a bioactive TGFβ2226/228 showed a significant increase in IOP after 2 weeks. When 1μM FUD was injected intracamerally into mice 2 weeks post Ad5-TGFβ2 injection, FUD significantly reduced IOP after 2 days. Neither mutated FUD (mFUD) nor PBS had any effect on IOP. Four days after FUD was injected, IOP returned to pre-FUD injection levels. In the absence of TGFβ2, intracameral injection of FUD had no effect on IOP. Western blotting of mouse anterior segments expressing TGFβ2 showed that FUD decreased fibronectin levels 2 days after intracameral injection (p<0.05) but not 7 days compared to eyes injected with PBS. mFUD injection had no significant effect on fibronectin levels at any time point. Immunofluorescence microscopy studies in human TM (HTM) cells showed that treatment with 2ng/ml TGFβ2 increased the amount of EDA+ and EDB+ fibronectin incorporated into fibrils and 2μM FUD decreased both EDA+ and EDB+ fibronectin in fibrils. An on-cell western assay validated this and showed that FUD caused a 67% reduction in deoxycholate insoluble fibronectin fibrils in the presence of TGFβ2. FUD also caused a 43% reduction in fibronectin fibrillogenesis in the absence of TGFβ2 while mFUD had no effect. These studies suggest that targeting the assembly of fibronectin fibrillogenesis may represent a way to control IOP.
Collapse
Affiliation(s)
- Jennifer A. Faralli
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Mark S. Filla
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Colleen M. McDowell
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Donna M. Peters
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
| |
Collapse
|
9
|
Kumar A, Cheng T, Song W, Cheuk B, Yang E, Yang L, Xie Y, Du Y. Two-step induction of trabecular meshwork cells from induced pluripotent stem cells for glaucoma. Biochem Biophys Res Commun 2020; 529:411-417. [PMID: 32703444 DOI: 10.1016/j.bbrc.2020.05.225] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 05/31/2020] [Indexed: 02/08/2023]
Abstract
Glaucoma is a leading cause of irreversible blindness worldwide. Reducing intraocular pressure is currently the only effective treatment. Elevated intraocular pressure is associated with increased resistance of the outflow pathway, mainly the trabecular meshwork (TM). Despite great progress in the field, the development of novel and effective treatment for glaucoma is still challenging. In this study, we reported that human induced pluripotent stem cells (iPSCs) can be cultured as colonies and monolayer cells expressing OCT4, alkaline phosphatase, SSEA4 and SSEA1. After induction to neural crest cells (NCCs) positive to NGFR and HNK1, the iPSCs can differentiate into TM cells. The induced iPSC-TM cells expressed TM cell marker CHI3L1, were responsive to dexamethasone treatment with increased expression of myocilin, ANGPTL7, and formed CLANs, comparable to primary TM cells. To the best of our knowledge, this is the first study that induces iPSCs to TM cells through a middle neural crest stage, which ensures a stable NCC pool and ensures the high output of the same TM cells. This system can be used to develop personalized treatments using patient-derived iPSCs, explore high throughput screening of new drugs focusing on TM response for controlling intraocular pressure, and investigate stem cell-based therapy for TM regeneration.
Collapse
Affiliation(s)
- Ajay Kumar
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tianyu Cheng
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Ophthalmology, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Weitao Song
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
| | - Brandon Cheuk
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Enzhi Yang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lei Yang
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yubing Xie
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY, USA
| | - Yiqin Du
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA, USA; Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA, USA.
| |
Collapse
|
10
|
Zhou Y, Xia X, Yang E, Wang Y, Marra KG, Ethier CR, Schuman JS, Du Y. Adipose-derived stem cells integrate into trabecular meshwork with glaucoma treatment potential. FASEB J 2020; 34:7160-7177. [PMID: 32259357 PMCID: PMC7254553 DOI: 10.1096/fj.201902326r] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 02/24/2020] [Accepted: 03/23/2020] [Indexed: 12/13/2022]
Abstract
The trabecular meshwork (TM) is an ocular tissue that maintains intraocular pressure (IOP) within a physiologic range. Glaucoma patients have reduced TM cellularity and, frequently, elevated IOP. To establish a stem cell-based approach to restoring TM function and normalizing IOP, human adipose-derived stem cells (ADSCs) were induced to differentiate to TM cells in vitro. These ADSC-TM cells displayed a TM cell-like genotypic profile, became phagocytic, and responded to dexamethasone stimulation, characteristic of TM cells. After transplantation into naive mouse eyes, ADSCs and ADSC-TM cells integrated into the TM tissue, expressed TM cell markers, and maintained normal IOP, outflow facility, and extracellular matrix. Cell migration and affinity results indicated that the chemokine pair CXCR4/SDF1 may play an important role in ADSC-TM cell homing. Our study demonstrates the possibility of applying autologous or allogeneic ADSCs and ADSC-TM cells as a potential treatment to restore TM structure and function in glaucoma.
Collapse
Affiliation(s)
- Yi Zhou
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China 410008
- Co-first author
| | - Xiaobo Xia
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China 410008
- Co-first author
| | - Enzhi Yang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213
| | - Yiwen Wang
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213
- Department of Ophthalmology, Xiangya Hospital, Central South University, Changsha, Hunan, China 410008
| | - Kacey G. Marra
- Departments of Plastic Surgery and Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213
| | - C. Ross Ethier
- Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA 30332
| | - Joel S. Schuman
- Department of Ophthalmology, New York University School of Medicine, New York, NY 10016
| | - Yiqin Du
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213
- Department of Developmental Biology, University of Pittsburgh, Pittsburgh, PA 15213
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15213
| |
Collapse
|
11
|
Tian YI, Zhang X, Torrejon K, Danias J, Gindina S, Nayyar A, Du Y, Xie Y. A bioengineering approach to Schlemm's canal-like stem cell differentiation for in vitro glaucoma drug screening. Acta Biomater 2020; 105:203-213. [PMID: 31982588 DOI: 10.1016/j.actbio.2020.01.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/30/2022]
Abstract
Human Schlemm's canal (HSC) cells are critical for understanding outflow physiology and glaucoma etiology. However, primary donor cells frequently used in research are difficult to isolate. HSC cells exhibit both vascular and lymphatic markers. Human adipose-derived stem cells (ADSCs) represent a potential source of HSC due to their capacity to differentiate into both vascular and lymphatic endothelial cells, via VEGF-A and VEGF-C. Shear stress plays a critical role in maintaining HSC integrity, function, and PROX1 expression. Additionally, the human trabecular meshwork (HTM) microenvironment could provide cues for HSC-like differentiation. We hypothesize that subjecting ADSCs to VEGF-A or VEGF-C, shear stress, and co-culture with HTM cells could provide biological, mechanical, and cellular cues necessary for HSC-like differentiation. To test this hypothesis, effects of VEGF-A, VEGF-C, and shear stress on ADSC differentiation were examined and compared to primary HSC cells in terms of cell morphology, and HSC marker expression using qPCR, immunoblotting, and immunocytochemistry analysis. Furthermore, the effect of co-culture with HTM cells on porous scaffolds on ADSC differentiation was studied. Treatment with VEGF-C under shear stress is effective in differentiating ADSCs into PROX1-expressing HSC-like cells. Co-culture with HTM cells on porous scaffolds leads to HTM/ADSC-derived HSC-like constructs that regulate through-flow and respond as expected to dexamethasone. STATEMENT OF SIGNIFICANCE: We successfully generated human Schlemm's canal (HSC) like cells from adipocyte-derived stem cells induced by biochemical and biomechanical cues as well as bioengineered human trabecular meshwork (HTM) on micropatterned, porous SU8 scaffolds. These stem cell-derived HSC-like cells co-cultured with HTM cells on SU8 scaffolds can regulate through-flow, and in particular, are responsive to steroid treatment as expected. These findings show that ADSC-derived HSC-like cells have the potential to recreate the ocular outflow pathway for in vitro glaucoma drug screening. To the best of our knowledge, it is the very first time to demonstrate derivation of Schlemm's canal-like cells from stem cells. It provides an important alternative source to primary Schlemm's canal cells that are very difficult to be isolated and cultured from human donors.
Collapse
Affiliation(s)
- Yangzi Isabel Tian
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Xulang Zhang
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA
| | - Karen Torrejon
- Glauconix Biosciences, Inc., 251 Fuller Road, Albany, NY 12203, USA
| | - John Danias
- SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY 11203, USA
| | - Sofya Gindina
- SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY 11203, USA
| | - Ashima Nayyar
- SUNY Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY 11203, USA
| | - Yiqin Du
- University of Pittsburg School of Medicine, 203 Lothrop Street, Pittsburgh, PA 15213, USA
| | - Yubing Xie
- College of Nanoscale Science and Engineering, SUNY Polytechnic Institute, 257 Fuller Road, Albany, NY 12203, USA.
| |
Collapse
|
12
|
Juliana FR, Kesse S, Boakye-Yiadom KO, Veroniaina H, Wang H, Sun M. Promising Approach in the Treatment of Glaucoma Using Nanotechnology and Nanomedicine-Based Systems. Molecules 2019; 24:E3805. [PMID: 31652593 PMCID: PMC6833088 DOI: 10.3390/molecules24203805] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 10/17/2019] [Accepted: 10/19/2019] [Indexed: 12/14/2022] Open
Abstract
Glaucoma is considered a leading cause of blindness with the human eye being one of the body's most delicate organs. Ocular diseases encompass diverse diseases affecting the anterior and posterior ocular sections, respectively. The human eye's peculiar and exclusive anatomy and physiology continue to pose a significant obstacle to researchers and pharmacologists in the provision of efficient drug delivery. Though several traditional invasive and noninvasive eye therapies exist, including implants, eye drops, and injections, there are still significant complications that arise which may either be their low bioavailability or the grave ocular adverse effects experienced thereafter. On the other hand, new nanoscience technology and nanotechnology serve as a novel approach in ocular disease treatment. In order to interact specifically with ocular tissues and overcome ocular challenges, numerous active molecules have been modified to react with nanocarriers. In the general population of glaucoma patients, disease growth and advancement cannot be contained by decreasing intraocular pressure (IOP), hence a spiking in future research for novel drug delivery systems and target therapeutics. This review focuses on nanotechnology and its therapeutic and diagnostic prospects in ophthalmology, specifically glaucoma. Nanotechnology and nanomedicine history, the human eye anatomy, research frontiers in nanomedicine and nanotechnology, its imaging modal quality, diagnostic and surgical approach, and its possible application in glaucoma will all be further explored below. Particular focus will be on the efficiency and safety of this new therapy and its advances.
Collapse
Affiliation(s)
| | - Samuel Kesse
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
- Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
| | - Kofi Oti Boakye-Yiadom
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
- Department of Pharmaceutics, School of Pharmacy, China Pharmaceutical University, Nanjing 211198, China.
| | - Hanitrarimalala Veroniaina
- State Key Laboratory of Modern Chinese Medicine, China Pharmaceutical University, Nanjing 210009, China.
| | - Huihui Wang
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China.
| | - Meihao Sun
- College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, China.
| |
Collapse
|
13
|
Wu Z, Huang C, Xu C, Xie L, Liang JJ, Liu L, Pang CP, Ng TK, Zhang M. Caveolin-1 regulates human trabecular meshwork cell adhesion, endocytosis, and autophagy. J Cell Biochem 2019; 120:13382-13391. [PMID: 30916825 DOI: 10.1002/jcb.28613] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 01/15/2019] [Accepted: 01/25/2019] [Indexed: 02/05/2023]
Abstract
Impaired trabecular meshwork (TM) outflow is implicated in the pathogenesis of primary open-angle glaucoma (POAG). We previously identified the association of a caveolin-1 (CAV1) variant with POAG by genome-wide association study. Here we report a study of CAV1 knockout (KO) effect on human TM cell properties. We generated human CAV1-KO TM cells by CRISPR/Cas9 technology, and we found that the CAV1-KO TM cells less adhered to the surface coating than the wildtype TM cells by 69.34% ( P < 0.05), but showed no difference in apoptosis. Higher endocytosis ability of dextran and transferrin was also observed in the CAV1-KO TM cells (4.37 and 1.89-fold respectively, P < 0.001), compared to the wildtype TM cells. Moreover, the CAV1-KO TM cells had higher expression of extracellular matrix-degrading enzyme genes ( ADMTS13 and MMP14) as well as autophagy-related genes ( ATG7 and BECN1) and protein (LC3B-II) than the wildtype TM cells. In summary, results from this study showed that the CAV1-KO TM cells have reduced adhesion with higher extracellular matrix-degrading enzyme expression, but increased endocytosis and autophagy activities, indicating that CAV1 could be involved in the regulation of adhesion, endocytosis, and autophagy in human TM cells.
Collapse
Affiliation(s)
- Zhenggen Wu
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Chukai Huang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Ciyan Xu
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Lijing Xie
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Jia-Jian Liang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Lifang Liu
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| | - Chi Pui Pang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Tsz Kin Ng
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
- Shantou University Medical College, Shantou, Guangdong, China
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Mingzhi Zhang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou, Guangdong, China
| |
Collapse
|
14
|
Keller KE, Bhattacharya SK, Borrás T, Brunner TM, Chansangpetch S, Clark AF, Dismuke WM, Du Y, Elliott MH, Ethier CR, Faralli JA, Freddo TF, Fuchshofer R, Giovingo M, Gong H, Gonzalez P, Huang A, Johnstone MA, Kaufman PL, Kelley MJ, Knepper PA, Kopczynski CC, Kuchtey JG, Kuchtey RW, Kuehn MH, Lieberman RL, Lin SC, Liton P, Liu Y, Lütjen-Drecoll E, Mao W, Masis-Solano M, McDonnell F, McDowell CM, Overby DR, Pattabiraman PP, Raghunathan VK, Rao PV, Rhee DJ, Chowdhury UR, Russell P, Samples JR, Schwartz D, Stubbs EB, Tamm ER, Tan JC, Toris CB, Torrejon KY, Vranka JA, Wirtz MK, Yorio T, Zhang J, Zode GS, Fautsch MP, Peters DM, Acott TS, Stamer WD. Consensus recommendations for trabecular meshwork cell isolation, characterization and culture. Exp Eye Res 2018; 171:164-173. [PMID: 29526795 PMCID: PMC6042513 DOI: 10.1016/j.exer.2018.03.001] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 03/01/2018] [Indexed: 12/30/2022]
Abstract
Cultured trabecular meshwork (TM) cells are a valuable model system to study the cellular mechanisms involved in the regulation of conventional outflow resistance and thus intraocular pressure; and their dysfunction resulting in ocular hypertension. In this review, we describe the standard procedures used for the isolation of TM cells from several animal species including humans, and the methods used to validate their identity. Having a set of standard practices for TM cells will increase the scientific rigor when used as a model, and enable other researchers to replicate and build upon previous findings.
Collapse
Affiliation(s)
| | | | | | | | | | - Abbott F Clark
- University of North Texas Health Sciences Center, United States
| | | | - Yiqin Du
- University of Pittsburgh, United States
| | | | | | | | - Thomas F Freddo
- Massachusetts College of Pharmacy and Health Sciences, United States
| | | | | | | | | | - Alex Huang
- University of California, Los Angeles, United States
| | | | | | | | | | | | | | | | | | | | - Shan C Lin
- University of California, San Francisco, United States
| | | | | | | | - Weiming Mao
- University of North Texas Health Sciences Center, United States
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - James C Tan
- University of Southern California, United States
| | | | | | | | - Mary K Wirtz
- Oregon Health and Science University, United States
| | - Thomas Yorio
- University of North Texas Health Sciences Center, United States
| | - Jie Zhang
- University of California, Los Angeles, United States
| | - Gulab S Zode
- University of North Texas Health Sciences Center, United States
| | - Michael P Fautsch
- Department of Ophthalmology, Mayo Clinic, 200 1st St SW, Rochester, MN 55905, United States.
| | - Donna M Peters
- Department of Pathology & Laboratory Medicine, University of Wisconsin, 1300 University Ave, Madison, WI 53706, United States.
| | - Ted S Acott
- Department of Ophthalmology, Department of Biochemistry & Molecular Biology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, United States.
| | - W Daniel Stamer
- Department of Ophthalmology, Duke University, DUMC 3802, Durham, NC 27705, United States.
| |
Collapse
|
15
|
Tabak S, Schreiber‐Avissar S, Beit‐Yannai E. Extracellular vesicles have variable dose-dependent effects on cultured draining cells in the eye. J Cell Mol Med 2018; 22:1992-2000. [PMID: 29411534 PMCID: PMC5824413 DOI: 10.1111/jcmm.13505] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 11/15/2017] [Indexed: 12/17/2022] Open
Abstract
The role of extracellular vesicles (EVs) as signal mediators has been described in many biological fields. How many EVs are needed to deliver the desired physiological signal is yet unclear. Using a normal trabecular meshwork (NTM) cell culture exposed to non-pigmented ciliary epithelium (NPCE)-derived EVs, a relevant model for studying the human ocular drainage system, we addressed the EVs dose-response effects on the Wnt signaling. The objective of the study was to investigate the dosing effects of NPCE-derived EVs on TM Wnt signaling. EVs were isolated by PEG 8000 method from NPCE and RPE cells (used as controls) conditioned media. Concentrations were determined by Tunable Resistive Pulse Sensing method. Various exosomes concentration were incubated with TM cells, for the determination of mRNA (β-Catenin, Axin2 and LEF1) and protein (β-Catenin, GSK-3β) expression using real-time quantitative PCR and Western blot, respectively. Exposure of NTM cells for 8 hrs to low EVs concentrations was associated with a significant decreased expression of β-Catenin, GSK-3β, as opposed to exposure to high exosomal concentrations. Pro-MMP9 and MMP9 activities were significantly enhanced in NTM cells treated with high EV concentrations of (X10) as compared to low EV concentrations of either NPCE- or RPE-derived EVs and to untreated control. Our data support the concept that EVs biological effects are concentration-dependent at their target site. Specifically in the present study, we described a general dose-response at the gene and MMPs activity and a different dose-response regarding key canonical Wnt proteins expression.
Collapse
Affiliation(s)
- Saray Tabak
- Clinical Biochemistry and Pharmacology DepartmentThe Faculty of Health SciencesBen‐Gurion University of the NegevBeer‐ShevaIsrael
| | - Sofia Schreiber‐Avissar
- Clinical Biochemistry and Pharmacology DepartmentThe Faculty of Health SciencesBen‐Gurion University of the NegevBeer‐ShevaIsrael
| | - Elie Beit‐Yannai
- Clinical Biochemistry and Pharmacology DepartmentThe Faculty of Health SciencesBen‐Gurion University of the NegevBeer‐ShevaIsrael
| |
Collapse
|
16
|
Abstract
Exosomes are extracellular nanovesicles that mediate a number of cellular processes, including intracellular signalling. There are many published examples of exosome-exosome dimers; however, their relevance has not been explored. Here, we propose that cells release exosomes to physically interact with incoming exosomes, forming dimers that we hypothesize attenuate incoming exosome-mediated signalling. We discuss experiments to test this hypothesis and potential relevance in health and disease.
Collapse
Affiliation(s)
- Elie Beit‐Yannai
- Clinical Biochemistry and Pharmacology departmentBen‐Gurion University of the NegevBeer‐ShevaIsrael
| | - Saray Tabak
- Clinical Biochemistry and Pharmacology departmentBen‐Gurion University of the NegevBeer‐ShevaIsrael
| | | |
Collapse
|
17
|
Duffy L, O'Reilly S. Functional Implications of Cross-Linked Actin Networks in Trabecular Meshwork Cells. Cell Physiol Biochem 2018; 45:783-794. [PMID: 29414811 DOI: 10.1159/000487170] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/29/2017] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS The Trabecular meshwork (TM) is the tissue responsible for outflow resistance and therefore intraocular pressure. TM cells contain a contractile apparatus that is composed of actin stress fibres which run parallel to the axis of the cell and are responsible for facilitating contraction. Cross-Linked Actin Networks (CLANs) are polygonal arrangements of actin that form a geodesic network found predominantly in TM cells both in situ and in vitro. The aim of this work is to determine the functional significance of CLANs in TM cells and to assess the effect of mechanical stretch stimulation on the induction (or not) of CLANs. METHODS We used collagen gel contraction models to demonstrate functional impairment of cells when induced to express CLANs in situ. Cyclic mechanical stretch was used to stimulate cells and measure CLANs Results: CLANs inhibited contraction and cyclic mechanical stretch induced CLANs. Furthermore, we also demonstrated that using shape alone we could predict the appearance of CLANs using a simple light microscopy technique. CONCLUSION Taken together we have now shown, for the first time, a functional deficit In TM cells with CLANs Furthermore that shape alone can predict the appearance of CLAN containing cells. CLANs can now be linked to a functional effect and may underlie the appearance of CLANs with the pathology of primary open angle glaucoma (POAG).
Collapse
|
18
|
Patel GC, Liu Y, Millar JC, Clark AF. Glucocorticoid receptor GRβ regulates glucocorticoid-induced ocular hypertension in mice. Sci Rep 2018; 8:862. [PMID: 29339763 PMCID: PMC5770444 DOI: 10.1038/s41598-018-19262-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 12/21/2017] [Indexed: 01/26/2023] Open
Abstract
Prolonged glucocorticoid (GC) therapy can cause GC-induced ocular hypertension (OHT), which if left untreated progresses to iatrogenic glaucoma and permanent vision loss. The alternatively spliced isoform of glucocorticoid receptor GRβ acts as dominant negative regulator of GR activity, and it has been shown that overexpressing GRβ in trabecular meshwork (TM) cells inhibits GC-induced glaucomatous damage in TM cells. The purpose of this study was to use viral vectors to selectively overexpress the GRβ isoform in the TM of mouse eyes treated with GCs, to precisely dissect the role of GRβ in regulating steroid responsiveness. We show that overexpression of GRβ inhibits GC effects on MTM cells in vitro and GC-induced OHT in mouse eyes in vivo. Ad5 mediated GRβ overexpression reduced the GC induction of fibronectin, collagen 1, and myocilin in TM of mouse eyes both in vitro and in vivo. GRβ also reversed DEX-Ac induced IOP elevation, which correlated with increased conventional aqueous humor outflow facility. Thus, GRβ overexpression reduces effects caused by GCs and makes cells more resistant to GC treatment. In conclusion, our current work provides the first evidence of the in vivo physiological role of GRβ in regulating GC-OHT and GC-mediated gene expression in the TM.
Collapse
Affiliation(s)
- Gaurang C Patel
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, United States
| | - Yang Liu
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, United States
| | - J Cameron Millar
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, United States
| | - Abbot F Clark
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX, 76107, United States.
| |
Collapse
|
19
|
Filla MS, Dimeo KD, Tong T, Peters DM. Disruption of fibronectin matrix affects type IV collagen, fibrillin and laminin deposition into extracellular matrix of human trabecular meshwork (HTM) cells. Exp Eye Res 2017; 165:7-19. [PMID: 28860021 PMCID: PMC5705399 DOI: 10.1016/j.exer.2017.08.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Revised: 06/02/2017] [Accepted: 08/27/2017] [Indexed: 10/19/2022]
Abstract
Fibronectin fibrils are a major component of the extracellular matrix (ECM) of the trabecular meshwork (TM). They are a key mediator of the formation of the ECM which controls aqueous humor outflow and contributes to the pathogenesis of glaucoma. The purpose of this work was to determine if a fibronectin-binding peptide called FUD, derived from the Streptococcus pyogenes Functional Upstream Domain of the F1 adhesin protein, could be used to control fibronectin fibrillogenesis and hence ECM formation under conditions where its expression was induced by treatment with the glucocorticoid dexamethasone. FUD was very effective at preventing fibronectin fibrillogenesis in the presence or absence of steroid treatment as well as the removal of existing fibronectin fibrils. Disruption of fibronectin fibrillogenesis by FUD also disrupted the incorporation of type IV collagen, laminin and fibrillin into the ECM. The effect of FUD on these other protein matrices, however, was found to be dependent upon the maturity of the ECM when FUD was added. FUD effectively disrupted the incorporation of these other proteins into matrices when added to newly confluent cells that were forming a nascent ECM. In contrast, FUD had no effect on these other protein matrices if the cell cultures already possessed a pre-formed, mature ECM. Our studies indicate that FUD can be used to control fibronectin fibrillogenesis and that these fibrils play a role in regulating the assembly of other ECM protein into matrices involving type IV collagen, laminin, and fibrillin within the TM. This suggests that under in vivo conditions, FUD would selectively disrupt fibronectin fibrils and de novo assembly of other proteins into the ECM. Finally, our studies suggest that targeting fibronectin fibril assembly may be a viable treatment for POAG as well as other glaucomas involving excessive or abnormal matrix deposition of the ECM.
Collapse
Affiliation(s)
- Mark S Filla
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, United States
| | - Kaylee D Dimeo
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, United States
| | - Tiegang Tong
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, United States
| | - Donna M Peters
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, United States; Ophthalmology & Visual Sciences, University of Wisconsin, Madison, WI 53706, United States.
| |
Collapse
|
20
|
Chu ZM, Li HB, Sun SX, Jiang YC, Wang B, Dong YF. Melatonin promotes osteoblast differentiation of bone marrow mesenchymal stem cells in aged rats. Eur Rev Med Pharmacol Sci 2017; 21:4446-4456. [PMID: 29077147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
OBJECTIVE The current study was to explore the effect of melatonin on osteoporosis and relevant mechanisms. MATERIALS AND METHODS We performed micro-CT to detect bone microstructure and ELISA to detect the contents of osteocalcin (OCN) and bone alkaline phosphatase (BAP) in serum. Double fluorescence labeling of calcein and tetracycline and toluidine blue staining were used to determine morphological indexes of bone tissues. Alizarin red staining and Oil Red O staining were performed to recognize bone cells and adipocytes. RT-PCR was performed to determine the expression of osteoblast differentiation related genes. RESULTS In the current study, data from micro-CT indicated that melatonin significantly increased the bone mass density (BMD), bone volume/tissue volume (BV/TV), trabecular number (Tb.N) and trabecular thickness (Tb.Th), and decreased the Structure Model Index (SMI) and trabecular Separation/Spacing (Tb.Sp) in elderly rats. Melatonin reduced calcium and phosphorus losses in urine and increased BAP and OCN levels in serum in elderly rats and increased bone formation rate (BFR) and bone mineralization rate (MAR) in elderly rats. Melatonin increased the number of osteoblasts in bone marrow and reduced the number of adipocytes in elderly rats. Melatonin also promoted the expression of osteogenic differentiation genes and suppressed the expression of adipogenic differentiation genes. CONCLUSIONS WE suggest that melatonin could alleviate osteoporosis in aged rats' models probably by promoting osteoblast differentiation.
Collapse
Affiliation(s)
- Z-M Chu
- Department of Orthopedics, The First People's Hospital of Lianyungang, Lianyungang City, Jiangsu Province, China.
| | | | | | | | | | | |
Collapse
|
21
|
Abstract
Small monomeric GTPases, including those belonging to the Rho family, regulate a diverse array of intracellular signaling pathways which affect vesicle transport/trafficking, endocytosis, cell cycle progression, cell contractility, and formation of stress fibers or focal adhesions. Functional activation of newly synthesized small monomeric GTPases is facilitated by a multistep post-translational process involving transferase-catalyzed addition of farnesyl or geranylgeranyl isoprenoids to conserved cysteine residues within a unique carboxy terminal CaaX motif. Here, using well-established and widely available contemporary methodologies, detailed protocols by which to semi-quantitatively evaluate the functional consequence of post-translational isoprenylation in human trabecular meshwork cells are described. We introduce the concept that isoprenylation alone is itself a key regulator of mammalian Rho GTPase expression and turnover.
Collapse
Affiliation(s)
- Evan B Stubbs
- Research Service, Department of Veterans Affairs, Edward Hines Jr. VA Hospital, Hines, IL, 60141, USA.
- Department of Ophthalmology, Stritch School of Medicine, Loyola University Chicago, 2160 South First Ave., LUH-North Entrance, Suite 2601, Maywood, IL, 60153, USA.
| |
Collapse
|
22
|
Meng B, Li H, Sun X, Qu W, Yang B, Cheng F, Shi L, Yuan H. σ-1 receptor stimulation protects against pressure-induced damage through InsR-MAPK signaling in human trabecular meshwork cells. Mol Med Rep 2017; 16:617-624. [PMID: 28560459 PMCID: PMC5482118 DOI: 10.3892/mmr.2017.6647] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Accepted: 03/21/2017] [Indexed: 01/27/2023] Open
Abstract
The purpose of the present study was to investigate the protective effect of the σ-1 receptor (Sig-1R) agonist (+)‑pentazocin (PTZ) on pressure-induced apoptosis and death of human trabecular meshwork cells (hTMCs). The expression levels of Sig‑1R and insulin receptor (InsR) were examined in hTMCs. Cells were cultured under a pressure of 0, 20, 40, 60 and 80 mmHg for 48 h, and under 80 mmHg for 44 h, after which the cells were treated with (+)‑PTZ (20 µM), N-(2-(3,4-dichlorophenyl)ethyl)-N‑methyl-2‑(dimethylamino) ethylamine (BD‑1063; 20 µM) administered 30 min prior to (+)‑PTZ, or BD‑1063 (20 µM) and then exposed to 80 mmHg again until the 48 h time‑point. The changes of the cells were observed by optical and electron microscopy, the apoptosis and death of hTMCs were detected by ethidium bromide/acridine orange dual staining assay and the expression of Sig‑1R and InsR by reverse transcription‑quantitative polymerase chain reaction and western blot analysis. The phosphorylation of extracellular signal‑regulated kinase (ERK), an important downstream protein of the InsR‑mitogen‑activated protein kinases (MAPK) signaling pathway, was also detected by western blot analysis when (+)‑PTZ and BD‑1063 were added to the 80 mmHg‑treated cells. Sig‑1Rs and InsRs were expressed in hTMCs. The apoptosis and death of hTMCs increased from 40 mmHg with 50% cell death when the pressure was at 80 mmHg and the structure of the cells noticeably changed. The expression of Sig‑1R and InsR increased along with the elevation of pressure. (+)‑PTZ decreased the apoptosis and death of hTMCs and increased the expression of Sig‑1R and InsR, and the phosphorylation of ERK. Such effects were blocked by BD‑1063. The present study suggested that Sig‑1R agonist (+)‑PTZ can protect hTMCs from pressure‑induced apoptosis and death by activating InsR and the MAPK signal pathway.
Collapse
Affiliation(s)
- Bo Meng
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Hongyi Li
- Department of Ophthalmology and Otorhinolaryngology, Hospital of Heilongjiang University, Harbin, Heilongjiang 150080, P.R. China
| | - Xian Sun
- Department of Oncology, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Wei Qu
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Binbin Yang
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Fang Cheng
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Liping Shi
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| | - Huiping Yuan
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150086, P.R. China
| |
Collapse
|
23
|
Bermudez JY, Webber HC, Brown B, Braun TA, Clark AF, Mao W. A Comparison of Gene Expression Profiles between Glucocorticoid Responder and Non-Responder Bovine Trabecular Meshwork Cells Using RNA Sequencing. PLoS One 2017; 12:e0169671. [PMID: 28068412 PMCID: PMC5222504 DOI: 10.1371/journal.pone.0169671] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 12/20/2016] [Indexed: 11/23/2022] Open
Abstract
The most common ocular side effect of glucocorticoid (GC) therapy is GC-induced ocular hypertension (OHT) and GC-induced glaucoma (GIG). GC-induced OHT occurs in about 40% of the general population, while the other 60% are resistant. This study aims to determine the genes and pathways involved in differential GC responsiveness in the trabecular meshwork (TM). Using paired bovine eyes, one eye was perfusion-cultured with 100nM dexamethasone (DEX), while the fellow eye was used to establish a bovine TM (BTM) cell strain. Based on maximum IOP change in the perfused eye, the BTM cell strain was identified as a DEX-responder or non-responder strain. Three responder and three non-responder BTM cell strains were cultured, treated with 0.1% ethanol or 100nM DEX for 7 days. RNA and proteins were extracted for RNA sequencing (RNAseq), qPCR, and Western immunoblotting (WB), respectively. Data were analyzed using the human and bovine genome databases as well as Tophat2 software. Genes were grouped and compared using Student’s t-test. We found that DEX induced fibronectin expression in responder BTM cells but not in non-responder cells using WB. RNAseq showed between 93 and 606 differentially expressed genes in different expression groups between responder and non-responder BTM cells. The data generated by RNAseq were validated using qPCR. Pathway analyses showed 35 pathways associated with differentially expressed genes. These genes and pathways may play important roles in GC-induced OHT and will help us to better understand differential ocular responsiveness to GCs.
Collapse
Affiliation(s)
- Jaclyn Y. Bermudez
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd. Fort Worth, TX, United States of America
| | - Hannah C. Webber
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd. Fort Worth, TX, United States of America
| | - Bartley Brown
- Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, IA, United States of America
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, United States of America
- Department of Biomedical Engineering, College of Engineering, University of Iowa, Iowa City, IA, United States of America
| | - Terry A. Braun
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd. Fort Worth, TX, United States of America
- Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, IA, United States of America
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, United States of America
- Department of Biomedical Engineering, College of Engineering, University of Iowa, Iowa City, IA, United States of America
| | - Abbot F. Clark
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd. Fort Worth, TX, United States of America
| | - Weiming Mao
- North Texas Eye Research Institute, University of North Texas Health Science Center, 3500 Camp Bowie Blvd. Fort Worth, TX, United States of America
- * E-mail:
| |
Collapse
|
24
|
Banerjee J, Leung CT, Li A, Peterson-Yantorno K, Ouyang H, Stamer WD, Civan MM. Regulatory Roles of Anoctamin-6 in Human Trabecular Meshwork Cells. Invest Ophthalmol Vis Sci 2017; 58:492-501. [PMID: 28125837 PMCID: PMC5283088 DOI: 10.1167/iovs.16-20188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 12/07/2016] [Indexed: 12/19/2022] Open
Abstract
Purpose Trabecular meshwork (TM) cell volume is a determinant of aqueous humor outflow resistance, and thereby IOP. Regulation of TM cell volume depends on chloride ion (Cl-) release through swelling-activated channels (ICl,Swell), whose pore is formed by LRRC8 proteins. Chloride ion release through swelling-activated channels has been reported to be regulated by calcium-activated anoctamins, but this finding is controversial. Particularly uncertain has been the effect of anoctamin Ano6, reported as a Ca2+-activated Cl- (CaCC) or cation channel in other cells. The current study tested whether anoctamin activity modifies volume regulation of primary TM cell cultures and cell lines. Methods Gene expression was studied with quantitative PCR, supplemented by reverse-transcriptase PCR and Western immunoblots. Currents were measured by ruptured whole-cell patch clamping and volume by electronic cell sizing. Results Primary TM cell cultures and the TM5 and GTM3 cell lines expressed Ano6 3 to 4 orders of magnitude higher than the other anoctamin CaCCs (Ano1 and Ano2). Ionomycin increased cell Ca2+ and activated macroscopic currents conforming to CaCCs in other cells, but displayed significantly more positive mean reversal potentials (+5 to +12 mV) than those displayed by ICl,Swell (-14 to -21 mV) in the same cells. Nonselective CaCC inhibitors (tannic acid>CaCCinh-A01) and transient Ano6 knockdown strongly inhibited ionomycin-activated currents, ICl,Swell and the regulatory volume response to hyposmotic swelling. Conclusions Ionomycin activates CaCCs associated with net cation movement in TM cells. These currents, ICl,Swell, and cell volume are regulated by Ano6. The findings suggest a novel clinically-relevant approach for altering cell volume, and thereby outflow resistance, by targeting Ano6.
Collapse
Affiliation(s)
- Juni Banerjee
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Chi-Ting Leung
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Ang Li
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
- Guangdong-Hong Kong - Macau Institute of CNS Regeneration, Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, China
| | - Kim Peterson-Yantorno
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| | - Huan Ouyang
- Guangdong-Hong Kong - Macau Institute of CNS Regeneration, Guangdong Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, China
| | - W. Daniel Stamer
- Departments of Ophthalmology and Biomedical Engineering, Duke University, DUMC 3802, Durham, North Carolina, United States
| | - Mortimer M. Civan
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
- Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
| |
Collapse
|
25
|
Dismuke WM, Klingeborn M, Stamer WD. Mechanism of Fibronectin Binding to Human Trabecular Meshwork Exosomes and Its Modulation by Dexamethasone. PLoS One 2016; 11:e0165326. [PMID: 27783649 PMCID: PMC5081181 DOI: 10.1371/journal.pone.0165326] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 10/10/2016] [Indexed: 12/13/2022] Open
Abstract
Exosomes are emerging as important mediators of cell-matrix interactions by means of specific adhesion proteins. Changes in the tissue-specific exosomal protein expression may underlie pathological conditions whereby extracellular matrix turnover and homeostasis is disrupted. Ocular hypertension due to extracellular matrix accumulation in the trabecular meshwork is a hallmark of glucocorticoid-induced glaucoma. In the trabecular meshwork, exosomal fibronectin mediates cell matrix interactions at cellular structures called “invadosomes”. Trabecular meshwork cells use invadosomes to turn over their surrounding matrix and maintain passageways for flow of aqueous humor. In this study, we observed that human trabecular meshwork explants treated with dexamethasone released exosomes with significantly reduced amounts of fibronectin bound per exosome. Further, we found that exosome-fibronectin binding is heparan sulfate-dependent, consistent with our observation that trabecular meshwork exosomes are enriched in the heparin/heparan sulfate binding annexins A2 and A6. In this way, dexamethasone-treated explants released exosomes with a significant reduction in annexin A2 and A6 per exosome. Interestingly, we did not detect exosomal matrix metalloproteinases, but we identified abundant dipeptidyl peptidase 4, a serine protease whose activity was reduced on exosomes isolated from dexamethasone-treated explants. Together, our findings demonstrate mechanistically how corticosteroid-induced alterations in exosomal adhesion cargo and properties can account for the pathological matrix accumulation seen in many glaucoma patients.
Collapse
Affiliation(s)
- W. Michael Dismuke
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - W. Daniel Stamer
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
26
|
Chamling X, Sluch VM, Zack DJ. The Potential of Human Stem Cells for the Study and Treatment of Glaucoma. Invest Ophthalmol Vis Sci 2016; 57:ORSFi1-6. [PMID: 27116666 PMCID: PMC5110236 DOI: 10.1167/iovs.15-18590] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/05/2016] [Indexed: 01/01/2023] Open
Abstract
PURPOSE Currently, the only available and approved treatments for glaucoma are various pharmacologic, laser-based, and surgical procedures that lower IOP. Although these treatments can be effective, they are not always sufficient, and they cannot restore vision that has already been lost. The goal of this review is to briefly assess current developments in the application of stem cell biology to the study and treatment of glaucoma and other forms of optic neuropathy. METHODS A combined literature review and summary of the glaucoma-related discussion at the 2015 "Sight Restoration Through Stem Cell Therapy" meeting that was sponsored by the Ocular Research Symposia Foundation (ORSF). RESULTS Ongoing advancements in basic and eye-related developmental biology have enabled researchers to direct murine and human stem cells along specific developmental paths and to differentiate them into a variety of ocular cell types of interest. The most advanced of these efforts involve the differentiation of stem cells into retinal pigment epithelial cells, work that has led to the initiation of several human trials. More related to the glaucoma field, there have been recent advances in developing protocols for differentiation of stem cells into trabecular meshwork and retinal ganglion cells. Additionally, efforts are being made to generate stem cell-derived cells that can be used to secrete neuroprotective factors. CONCLUSIONS Advancing stem cell technology provides opportunities to improve our understanding of glaucoma-related biology and develop models for drug development, and offers the possibility of cell-based therapies to restore sight to patients who have already lost vision.
Collapse
Affiliation(s)
- Xitiz Chamling
- Department of Ophthalmology Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Valentin M. Sluch
- Department of Ophthalmology Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| | - Donald J. Zack
- Department of Ophthalmology Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
- Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States
| |
Collapse
|
27
|
Raghunathan VK, Morgan JT, Park SA, Weber D, Phinney BS, Murphy CJ, Russell P. Dexamethasone Stiffens Trabecular Meshwork, Trabecular Meshwork Cells, and Matrix. Invest Ophthalmol Vis Sci 2015; 56:4447-59. [PMID: 26193921 PMCID: PMC4509060 DOI: 10.1167/iovs.15-16739] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 05/22/2015] [Indexed: 02/06/2023] Open
Abstract
PURPOSE Treatment with corticosteroids can result in ocular hypertension and may lead to the development of steroid-induced glaucoma. The extent to which biomechanical changes in trabecular meshwork (TM) cells and extracellular matrix (ECM) contribute toward this dysfunction is poorly understood. METHODS Primary human TM (HTM) cells were cultured for either 3 days or 4 weeks in the presence or absence of dexamethasone (DEX), and cell mechanics, matrix mechanics and proteomics were determined, respectively. Adult rabbits were treated topically with either 0.1% DEX or vehicle over 3 weeks, and mechanics of the TM were determined. RESULTS Treatment with DEX for 3 days resulted in a 2-fold increase in HTM cell stiffness, and this correlated with activation of extracellular signal-related kinase 1/2 (ERK1/2) and overexpression of α-smooth muscle actin (αSMA). Further, the matrix deposited by HTM cells chronically treated with DEX is approximately 4-fold stiffer, more organized, and has elevated expression of matrix proteins commonly implicated in glaucoma (decorin, myocilin, fibrillin, secreted frizzle-related protein [SFRP1], matrix-gla). Also, DEX treatment resulted in a 3.5-fold increase in stiffness of the rabbit TM. DISCUSSION This integrated approach clearly demonstrates that DEX treatment increases TM cell stiffness concurrent with elevated αSMA expression and activation of the mitogen-activated protein kinase (MAPK) pathway, stiffens the ECM in vitro along with upregulation of Wnt antagonists and fibrotic markers embedded in a more organized matrix, and increases the stiffness of TM tissues in vivo. These results demonstrate glucocorticoid treatment can initiate the biophysical alteration associated with increased resistance to aqueous humor outflow and the resultant increase in IOP.
Collapse
Affiliation(s)
- Vijay Krishna Raghunathan
- Department of Surgical and Radiological Sciences School of Veterinary Medicine, University of California Davis, Davis, California, United States
| | - Joshua T. Morgan
- Department of Surgical and Radiological Sciences School of Veterinary Medicine, University of California Davis, Davis, California, United States
| | - Shin Ae Park
- Department of Surgical and Radiological Sciences School of Veterinary Medicine, University of California Davis, Davis, California, United States
| | - Darren Weber
- University of California Davis Genome Center Proteomics Core Facility, University of California Davis, Davis, California, United States
| | - Brett S. Phinney
- University of California Davis Genome Center Proteomics Core Facility, University of California Davis, Davis, California, United States
| | - Christopher J. Murphy
- Department of Surgical and Radiological Sciences School of Veterinary Medicine, University of California Davis, Davis, California, United States
- Department of Ophthalmology and Vision Sciences, School of Medicine, University of California Davis, Davis, California, United States
| | - Paul Russell
- Department of Surgical and Radiological Sciences School of Veterinary Medicine, University of California Davis, Davis, California, United States
| |
Collapse
|
28
|
Morgan JT, Raghunathan VK, Chang YR, Murphy CJ, Russell P. The intrinsic stiffness of human trabecular meshwork cells increases with senescence. Oncotarget 2015; 6:15362-74. [PMID: 25915531 PMCID: PMC4558157 DOI: 10.18632/oncotarget.3798] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 03/20/2015] [Indexed: 12/26/2022] Open
Abstract
Dysfunction of the human trabecular meshwork (HTM) plays a central role in the age-associated disease glaucoma, a leading cause of irreversible blindness. The etiology remains poorly understood but cellular senescence, increased stiffness of the tissue, and the expression of Wnt antagonists such as secreted frizzled related protein-1 (SFRP1) have been implicated. However, it is not known if senescence is causally linked to either stiffness or SFRP1 expression. In this study, we utilized in vitro HTM senescence to determine the effect on cellular stiffening and SFRP1 expression. Stiffness of cultured cells was measured using atomic force microscopy and the morphology of the cytoskeleton was determined using immunofluorescent analysis. SFRP1 expression was measured using qPCR and immunofluorescent analysis. Senescent cell stiffness increased 1.88±0.14 or 2.57±0.14 fold in the presence or absence of serum, respectively. This was accompanied by increased vimentin expression, stress fiber formation, and SFRP1 expression. In aggregate, these data demonstrate that senescence may be a causal factor in HTM stiffening and elevated SFRP1 expression, and contribute towards disease progression. These findings provide insight into the etiology of glaucoma and, more broadly, suggest a causal link between senescence and altered tissue biomechanics in aging-associated diseases.
Collapse
Affiliation(s)
- Joshua T. Morgan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Vijay Krishna Raghunathan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Yow-Ren Chang
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| | - Christopher J. Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
- Department of Ophthalmology &; Vision Science, School of Medicine, University of California, Davis, CA, USA
| | - Paul Russell
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA, USA
| |
Collapse
|
29
|
Lerner N, Beit-Yannai E. Cross-talk between ciliary epithelium and trabecular meshwork cells in-vitro: a new insight into glaucoma. PLoS One 2014; 9:e112259. [PMID: 25389776 PMCID: PMC4229184 DOI: 10.1371/journal.pone.0112259] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/06/2014] [Indexed: 12/17/2022] Open
Abstract
PURPOSE It is assumed that the non-pigmented ciliary epithelium plays a role in regulating intraocular pressure via its neuroendocrine activities. To test this hypothesis, we investigated the effect on a human trabecular meshwork (TM) cell line (NTM) of co-culture with a human non-pigmented ciliary epithelium cell line (ODM-2). METHODS The cellular cross-talk between ODM-2 and NTM cells was studied in a co-culture system in which the two cell types were co-cultured for 5 to 60 min or 2, 4 and 8h and then removed from the co-culture and analyzed. Analyses of the ERK and p38 mitogen-activated protein kinase (MAPK) pathways and of the activity of TM phosphatases and matrix metalloproteins (MMPs) were performed. Acid and alkaline phosphatase activity was determined by the DiFMUP (6, 8-difluoro-4-methylumbelliferyl phosphate) assay. MMP levels were determined by gelatin zymography. RESULTS Exposure of NTM cells to ODM-2 cells led to the activation of the MAPK signal transduction pathways in NTM cells within 5 min of co-culture. Phosphorylation of ERK1/ERK2 and p38 peaked at 10 and 15 min and then decreased over time. Interaction between ODM-2 and NTM cells promoted the expression of MMP-9 in the NTM cells after 4h of co-culture. CONCLUSIONS Our findings provide support for the hypothesis that crosstalk does indeed take place between ODM-2 and NTM cells. Future studies should be designed to determine the relationship between the MMP system, MAPK kinases and phosphatases. Manipulation of these signaling molecules and the related NTM signal transduction pathways may provide targets for developing improved treatments for glaucoma.
Collapse
Affiliation(s)
- Natalie Lerner
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Elie Beit-Yannai
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| |
Collapse
|
30
|
Filla MS, Clark R, Peters DM. A syndecan-4 binding peptide derived from laminin 5 uses a novel PKCε pathway to induce cross-linked actin network (CLAN) formation in human trabecular meshwork (HTM) cells. Exp Cell Res 2014; 327:171-82. [PMID: 25128150 PMCID: PMC4164596 DOI: 10.1016/j.yexcr.2014.07.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 07/17/2014] [Accepted: 07/22/2014] [Indexed: 12/31/2022]
Abstract
In this study, we examined the role(s) of syndecan-4 in regulating the formation of an actin geodesic dome structure called a cross-linked actin network (CLAN) in which syndecan-4 has previously been localized. CLANs have been described in several different cell types, but they have been most widely studied in human trabecular meshwork (HTM) cells where they may play a key role in controlling intraocular pressure by regulating aqueous humor outflow from the eye. In this study we show that a loss of cell surface synedcan-4 significantly reduces CLAN formation in HTM cells. Analysis of HTM cultures treated with or without dexamethasone shows that laminin 5 deposition within the extracellular matrix is increased by glucocorticoid treatment and that a laminin 5-derived, syndecan-4-binding peptide (PEP75), induces CLAN formation in TM cells. This PEP75-induced CLAN formation was inhibited by heparin and the broad spectrum PKC inhibitor Ro-31-7549. In contrast, the more specific PKCα inhibitor Gö 6976 had no effect, thus excluding PKCα as a downstream effector of syndecan-4 signaling. Analysis of PKC isozyme expression showed that HTM cells also expressed both PKCγ and PKCε. Cells treated with a PKCε agonist formed CLANs while a PKCα/γ agonist had no effect. These data suggest that syndecan-4 is essential for CLAN formation in HTM cells and that a novel PKCε-mediated signaling pathway can regulate formation of this unique actin structure.
Collapse
Affiliation(s)
- Mark S Filla
- Department of Ophthalmology & Visual Sciences, Medical Science Center, 1300 University Avenue, Madison, WI 53706, United States.
| | - Ross Clark
- Department of Pathology & Laboratory Medicine, Medical Science Center, 1300 University Avenue, Madison, WI 53706, United States.
| | - Donna M Peters
- Department of Ophthalmology & Visual Sciences, Medical Science Center, 1300 University Avenue, Madison, WI 53706, United States; Department of Pathology & Laboratory Medicine, Medical Science Center, 1300 University Avenue, Madison, WI 53706, United States.
| |
Collapse
|
31
|
Ren PL, Fan XJ, Yang XL, Liu MJ, Liu J, Huang JJ. [SIRT1 promote GTM cell DSBs repair and resist cellular senescence]. Sichuan Da Xue Xue Bao Yi Xue Ban 2014; 45:572-577. [PMID: 25286678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
OBJECTIVE To study the relationship between SIRT1 and glaucoma trabecular meshwork cell (GTM) cell on DNA double-strand breaks (DSBs) repair capability and resist cellular senescence. METHODS The expressions of SIRT1 in GTM and normal trabecular meshwork (HTM) cell detected by RT-RCR and Western blot; HTM and GTM cells divided into four groups separately: Res group (treat cells with 0.5 micromol/L Resveratrol for 24 h), SIRT1-ShRNA group (cells infected with recombinant SIRT1-ShRNA), microRNA34a group (cells infected with recombinant microRNA34a) and control group. The expression level of SIRT1 in groups was detected by Western blot. SA-beta-Gal staining was applied to each group of cells at 10 h, 32 h, 3 d and 6 d to evaluate the senescence of the cells. DSBs and the expression of gamma-H2AX after treated with 1.33 mol/L H2O2 at 0 h, 1 h, 2 h were detected by comet electrophoresis and Western blot. RESULTS The expression of SIRT1 were observed in both HTM and GTM cells, but the expression level in HTM was higher than that of GTM cells have the ability to express SIRT1, however the expression of SIRT1 was lower than HTM. Expression levels of SIRT1 presented following treads: Res > Control > microRNA34a > SIRT1-ShRNA. The dgree of senescence in GTM was higher than that in HTM cells when detected at the same time point with SA-beta-Gal staining. In the same cell line, the signs of senescence were appeared firstly and seriously in the cells treated with SIRT1-ShRNA in a time-dependent manner. Differently, after 24 h treatment with Res, the degree of senescence was decreased. The DSBs in GTM group was more than that of HTM group after treatment with oxidant when detected with Comet Electrophoresis and the the trends of the change was SIRT1-ShRNA > microRNA34a > Control > Res. The similar results also observed in the expression of gamma-H2AX. CONCLUSION SIRT1 may be useful in predicting the development and prognosis of glaucoma; Res promotes the expression of SIRT1 significantly, and the SIRT1 may protects GTM from oxidative stress-induced DSBs, aging even apoptosis, and promotes cell cycle arrest, which may provide a new target to treat glaucoma.
Collapse
|
32
|
Abstract
We have developed a tissue-based model of the human trabecular meshwork (TM) using viable postmortem corneoscleral donor tissue. Two-photon microscopy is used to optically section and image deep in the tissue to analyze cells and extracellular matrix (ECM) within the original three-dimensional (3D) environment of the TM. Multimodal techniques, including autofluorescence (AF), second harmonic generation (SHG), intravital dye fluorescence, and epifluorescence, are combined to provide unique views of the tissue at the cellular and subcellular level. SHG and AF imaging are non-invasive tissue imaging techniques with potential for clinical application, which can be modeled in the system. We describe the following in the tissue-based model: analysis of live cellularity to determine tissue viability; characteristics of live cells based on intravital labeling; features and composition of the TM's structural ECM; localization of specific ECM proteins to regions such as basement membrane; in situ induction and expression of tissue markers characteristic of cultured TM cells relevant to glaucoma; analysis of TM actin and pharmacological effects; in situ visualization of TM, inner wall endothelium, and Schlemm's canal; and application of 3D reconstruction, modeling, and quantitative analysis to the TM. The human model represents a cost-effective use of valuable and scarce yet available human tissue that allows unique cell biology, pharmacology, and translational studies of the TM.
Collapse
Affiliation(s)
- Edward R Chu
- Department of Ophthalmology, Keck School of Medicine, University of Southern California , Los Angeles, California
| | | | | |
Collapse
|
33
|
Fuchshofer R, Kuespert S, Junglas B, Tamm ER. The prostaglandin f2α analog fluprostenol attenuates the fibrotic effects of connective tissue growth factor on human trabecular meshwork cells. J Ocul Pharmacol Ther 2014; 30:237-45. [PMID: 24576038 DOI: 10.1089/jop.2013.0205] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
UNLABELLED Abstract Purpose: The trabecular meshwork (TM) outflow pathways of the aqueous humor show an increase in extracellular matrix in patients with primary open-angle glaucoma (POAG). The increase in TM extracellular matrix appears to be caused by transforming growth factor-β signaling and its downstream mediator connective-tissue growth factor (CTGF). Here we studied whether treatment with the prostaglandin F2α analog fluprostenol modulates the CTGF-mediated increase of the TM extracellular matrix. METHODS Human TM cells from 3 different donors were treated with CTGF (50 ng/mL) and/or fluprostenol (10(-6) M and 10(-7) M) and were analyzed by real-time reverse transcription polymerase chain reaction and Western blotting. Cell supernatants of the treated cells were analyzed by zymography. RESULTS Treatment with CTGF induced the expression and synthesis of CTGF, fibronectin, collagen type IV and VI, while treatment with fluprostenol alone had no effects. The effects of CTGF were blocked by 1-h pretreatment with fluprostenol in a dose-dependent manner. Treatment with fluprostenol or combined fluprostenol/CTGF induced the activity of matrix metalloproteinase 2 (MMP2) in TM cells, whereas treatment with CTGF alone had no effects on MMP2 activity. CONCLUSIONS Fluprostenol blocks the fibrotic effects of CTGF on human TM cells and increases the activity of MMP2. Both effects have the distinct potential to attenuate a CTGF-mediated increase in TM extracellular matrix in patients with POAG and any effects on TM outflow resistance that may result from that.
Collapse
Affiliation(s)
- Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg , Regensburg, Germany
| | | | | | | |
Collapse
|
34
|
Abstract
PURPOSE To investigate the antioxidant properties and biological functions of ascorbic acid (AA) on trabecular meshwork (TM) cells. METHODS Primary cultures of porcine TM cells were supplemented for 10 days with increasing concentrations of AA. Antioxidant properties against cytotoxic effect of H2O2 were evaluated by monitoring cell viability. Redox-active iron was quantified using calcein-AM. Intracellular reactive oxygen species (iROS) production was quantified using H2DCFDA. Ferritin and cathepsin protein levels were analyzed by Western blot. Autophagy was evaluated by monitoring lipidation of LC3-I to LC3-II. Lysosomal proteolysis and cathepsins activities were quantified using specific fluorogenic substrates. RESULTS AA exerts a dual effect against oxidative stress in TM cells, acting as an anti-oxidant or a pro-oxidant, depending on the concentration used. The pro-oxidant effect of AA was mediated by free intracellular iron and correlated with increased protein levels of ferritin and elevated iROS. In contrast, antioxidant properties correlated with lower ferritin and basal iROS content. Ascorbic acid supplementation also caused induction of autophagy, as well as increased lysosomal proteolysis, with the latter resulting from higher proteolytic activation of lysosomal cathepsins in treated cultures. CONCLUSIONS Our results suggest that the reported decrease of AA levels in plasma and aqueous humor can compromise lysosomal degradation in the outflow pathway cells with aging and contribute to the pathogenesis of glaucoma. Restoration of physiological levels of vitamin C inside the cells might improve their ability to degrade proteins within the lysosomal compartment and recover tissue function.
Collapse
Affiliation(s)
- Ping Xu
- Department of Ophthalmology, Duke University , Durham, North Carolina
| | | | | | | |
Collapse
|
35
|
Porter K, Lin Y, Liton PB. Cathepsin B is up-regulated and mediates extracellular matrix degradation in trabecular meshwork cells following phagocytic challenge. PLoS One 2013; 8:e68668. [PMID: 23844232 PMCID: PMC3700899 DOI: 10.1371/journal.pone.0068668] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Accepted: 06/01/2013] [Indexed: 12/24/2022] Open
Abstract
Cells in the trabecular meshwork (TM), a tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic activity in TM cells is thought to play an important role in outflow pathway physiology. However, the molecular mechanisms triggered by phagocytosis in TM cells are unknown. Here we investigated the effects of chronic phagocytic stress on lysosomal function using different phagocytic ligands (E. coli, carboxylated beads, collagen I-coated beads, and pigment). Lysotracker red co-localization and electron micrographs showed the maturation of E. coli- and collagen I-coated beads-containing phagosomes into phagolysosomes. Maturation of phagosomes into phagolysosomes was not observed with carboxylated beads or pigment particles. In addition, phagocytosis of E. coli and collagen I-coated beads led to increased lysosomal mass, and the specific up-regulation and activity of cathepsin B (CTSB). Higher levels of membrane-bound and secreted CTSB were also detected. Moreover, in vivo zymography showed the intralysosomal degradation of ECM components associated with active CTSB, as well as an overall increased gelatinolytic activity in phagocytically challenged TM cells. This increased gelatinolytic activity with phagocytosis was partially blocked with an intracellular CTSB inhibitor. Altogether, these results suggest a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.
Collapse
Affiliation(s)
- Kristine Porter
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Yizhi Lin
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Paloma B. Liton
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
36
|
Pattabiraman PP, Pecen PE, Rao PV. MRP4-mediated regulation of intracellular cAMP and cGMP levels in trabecular meshwork cells and homeostasis of intraocular pressure. Invest Ophthalmol Vis Sci 2013; 54:1636-49. [PMID: 23385799 PMCID: PMC3626514 DOI: 10.1167/iovs.12-11107] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 01/07/2013] [Accepted: 01/26/2013] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Multidrug, resistance-associated protein-4 (MRP4) is a membrane transporter that regulates the cellular efflux of cyclic nucleotides (cAMP and cGMP) involved in various physiologic responses. This study examined the expression and distribution of MRP4 in the trabecular meshwork (TM) cells and its role in homeostasis of IOP. METHODS Expression and distribution of MRP4 in human TM (HTM) cells and aqueous humor (AH) outflow pathway was determined by RT-PCR, immunoblotting, and immunofluorescence. Effects of inhibiting MRP4 activity and suppression of MRP4 expression on cAMP and cGMP levels, myosin light chain (MLC) phosphorylation, actin filament organization and activity of protein kinase G (PKG), protein kinase A (PKA), Rho guanosine triphosphatase (GTPase), and MLC phosphatase was monitored in HTM cells using ELISA, siRNA, biochemical, and immunofluorescence analyses. Topical application of the MRP4 inhibitor MK571 was tested to assess changes in IOP in rabbits. RESULTS RT-PCR, immunoblot, and immunofluorescence analyses confirmed the expression of MRP4 in HTM cells and distribution in human AH outflow pathway. Inhibition of MRP4 in HTM cells by MK571 or probenecid resulted in cell shape changes and decreases in actin stress fibers and MLC phosphorylation. Levels of intracellular cAMP and cGMP in HTM cells were increased significantly under these conditions. MK571-induced HTM cell relaxation appeared to be mediated predominantly via activation of the cGMP-dependent PKG signaling pathway. Topical application of MK571 significantly decreased IOP in Dutch-Belted rabbits. CONCLUSIONS These observations reveal that cyclic nucleotide efflux controlling transporter-MRP4 plays a significant role in IOP homeostasis potentially by regulating the relaxation characteristics of AH outflow pathway cells.
Collapse
Affiliation(s)
| | | | - Ponugoti Vasantha Rao
- From the Departments of
Ophthalmology and
- Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
| |
Collapse
|
37
|
Luna C, Li G, Huang J, Qiu J, Wu J, Yuan F, Epstein DL, Gonzalez P. Regulation of trabecular meshwork cell contraction and intraocular pressure by miR-200c. PLoS One 2012; 7:e51688. [PMID: 23272142 PMCID: PMC3522713 DOI: 10.1371/journal.pone.0051688] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 11/05/2012] [Indexed: 01/20/2023] Open
Abstract
Lowering intraocular pressure (IOP) delays or prevents the loss of vision in primary open-angle glaucoma (POAG) patients with high IOP and in those with normal tension glaucoma showing progression. Abundant evidence demonstrates that inhibition of contractile machinery of the trabecular meshwork cells is an effective method to lower IOP. However, the mechanisms involved in the regulation of trabecular contraction are not well understood. Although microRNAs have been shown to play important roles in the regulation of multiple cellular functions, little is known about their potential involvement in the regulation of IOP. Here, we showed that miR-200c is a direct postranscriptional inhibitor of genes relevant to the physiologic regulation of TM cell contraction including the validated targets Zinc finger E-box binding homeobox 1 and 2 (ZEB1 and ZEB2), and formin homology 2 domain containing 1 (FHOD1), as well as three novel targets: lysophosphatidic acid receptor 1 (LPAR1/EDG2), endothelin A receptor (ETAR), and RhoA kinase (RHOA). Consistently, transfection of TM cells with miR-200c resulted in strong inhibition of contraction in collagen populated gels as well as decreased cell traction forces exerted by individual TM cells. Finally, delivery of miR-200c to the anterior chamber of living rat eyes resulted in a significant decrease in IOP, while inhibition of miR-200c using an adenoviral vector expressing a molecular sponge led to a significant increase in IOP. These results demonstrate for the first time the ability of a miRNA to regulate trabecular contraction and modulate IOP in vivo, making miR-200c a worthy candidate for exploring ways to alter trabecular contractility with therapeutic purposes in glaucoma.
Collapse
Affiliation(s)
- Coralia Luna
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Guorong Li
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Jianyong Huang
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Jianming Qiu
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Jing Wu
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Fan Yuan
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - David L. Epstein
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| | - Pedro Gonzalez
- Department of Ophthalmology, Duke University, Durham, North Carolina, United States of America
| |
Collapse
|
38
|
Keller KE, Sun YY, Vranka JA, Hayashi L, Acott TS. Inhibition of hyaluronan synthesis reduces versican and fibronectin levels in trabecular meshwork cells. PLoS One 2012; 7:e48523. [PMID: 23139787 PMCID: PMC3489675 DOI: 10.1371/journal.pone.0048523] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 09/26/2012] [Indexed: 01/08/2023] Open
Abstract
Hyaluronan (HA) is a major component of the extracellular matrix (ECM) and is synthesized by three HA synthases (HAS). Similarities between the HAS2 knockout mouse and the hdf mutant mouse, which has a mutation in the versican gene, suggest that HA and versican expression may be linked. In this study, the relationship between HA synthesis and levels of versican, fibronectin and several other ECM components in trabecular meshwork cells from the anterior segment of the eye was investigated. HA synthesis was inhibited using 4-methylumbelliferone (4MU), or reduced by RNAi silencing of each individual HAS gene. Quantitative RT-PCR and immunoblotting demonstrated a reduction in mRNA and protein levels of versican and fibronectin. Hyaluronidase treatment also reduced versican and fibronectin levels. These effects could not be reversed by addition of excess glucose or glucosamine or exogenous HA to the culture medium. CD44, tenascin C and fibrillin-1 mRNA levels were reduced by 4MU treatment, but SPARC and CSPG6 mRNA levels were unaffected. Immunostaining of trabecular meshwork tissue after exposure to 4MU showed an altered localization pattern of HA-binding protein, versican and fibronectin. Reduction of versican by RNAi silencing did not affect HA concentration as assessed by ELISA. Together, these data imply that HA concentration affects synthesis of certain ECM components. Since precise regulation of the trabecular meshwork ECM composition and organization is required to maintain the aqueous humor outflow resistance and intraocular pressure homeostasis in the eye, coordinated coupling of HA levels and several of its ECM binding partners should facilitate this process.
Collapse
Affiliation(s)
- Kate E Keller
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA.
| | | | | | | | | |
Collapse
|
39
|
Abstract
BACKGROUND Myocilin is a gene linked to the most prevalent form of glaucoma, a major blinding disease. The trabecular meshwork (TM), a specialized eye tissue, is believed to be involved, at least in part, in the development of glaucoma. The Pro³⁷⁰ to Leu (P370L) mutation of myocilin is associated with severe glaucoma phenotypes and Gln³⁶⁸ stop (Q368X) is the most common myocilin mutation reported. Myocilin, upon overexpression, has been shown to induce phenotypes that include a loss of actin stress fibers, an increase in the cAMP level and protein kinase A (PKA) activity, as well as a reduction in the RhoA activity. We examined herein whether Wnt signaling pathway is involved in the myocilin phenotypes and whether P370L and Q368X mutants also display biological effects similar to those of the wild type myocilin. METHODOLOGY/PRINCIPAL FINDINGS Wild type myocilin, when transfected into cultured human TM cells, induced a loss of actin stress fibers as judged by phalloidin staining. Such a loss was averted by treatment of secreted Frizzled-related protein 1 (sFRP1), an inhibitor of Wnt signaling. Consistent with the notion that Wnt pathway mediates the myocilin phenotype, Wnt activation was demonstrated by TOP/FOP-Flash reporter assays. Treatment of human TM cells of a Wnt activator, SB216763, as well as transfection of myocilin P370L and Q368X mutants all resulted in actin stress fiber loss, PKA activation and RhoA inactivation. The PKA elevation was obviated by the sFRP1 treatment, indicating that Wnt signaling was upstream that of PKA. CONCLUSIONS/SIGNIFICANCE The present study demonstrated that following forced expression of wild type myocilin, Wnt was activated, triggering in turn other myocilin-related alterations. P370L and Q368X mutations induced similar phenotypes, suggesting one possible mechanism how the mutants may lead to TM cell damage and pathology.
Collapse
Affiliation(s)
- Xiang Shen
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago College of Medicine, Chicago, Illinois, United States of America
| | - Hongyu Ying
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago College of Medicine, Chicago, Illinois, United States of America
| | - Beatrice Y. J. T. Yue
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago College of Medicine, Chicago, Illinois, United States of America
| |
Collapse
|
40
|
Iyer P, Lalane R, Morris C, Challa P, Vann R, Rao PV. Autotaxin-lysophosphatidic acid axis is a novel molecular target for lowering intraocular pressure. PLoS One 2012; 7:e42627. [PMID: 22916143 PMCID: PMC3423407 DOI: 10.1371/journal.pone.0042627] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 07/09/2012] [Indexed: 11/18/2022] Open
Abstract
Primary open-angle glaucoma is the second leading cause of blindness in the United States and is commonly associated with elevated intraocular pressure (IOP) resulting from diminished aqueous humor (AH) drainage through the trabecular pathway. Developing effective therapies for increased IOP in glaucoma patients requires identification and characterization of molecular mechanisms that regulate IOP and AH outflow. This study describes the identification and role of autotaxin (ATX), a secretory protein and a major source for extracellular lysophosphatidic acid (LPA), in regulation of IOP in a rabbit model. Quantitative proteomics analysis identified ATX as an abundant protein in both human AH derived from non-glaucoma subjects and in AH from different animal species. The lysophospholipase D (LysoPLD) activity of ATX was found to be significantly elevated (by ∼1.8 fold; n=20) in AH derived from human primary open angle glaucoma patients as compared to AH derived from age-matched cataract control patients. Immunoblotting analysis of conditioned media derived from primary cultures of human trabecular meshwork (HTM) cells has confirmed secretion of ATX and the ability of cyclic mechanical stretch of TM cells to increase the levels of secreted ATX. Topical application of a small molecular chemical inhibitor of ATX (S32826), which inhibited AH LysoPLD activity in vitro (by >90%), led to a dose-dependent and significant decrease of IOP in Dutch-Belted rabbits. Single intracameral injection of S32826 (∼2 µM) led to significant reduction of IOP in rabbits, with the ocular hypotensive response lasting for more than 48 hrs. Suppression of ATX expression in HTM cells using small-interfering RNA (siRNA) caused a decrease in actin stress fibers and myosin light chain phosphorylation. Collectively, these observations indicate that the ATX-LPA axis represents a potential therapeutic target for lowering IOP in glaucoma patients.
Collapse
Affiliation(s)
- Padma Iyer
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Robert Lalane
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Corey Morris
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Pratap Challa
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Robin Vann
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
41
|
Acharya M, Sharp MW, Mirzayans F, Footz T, Huang L, Birdi C, Walter MA. Yeast two-hybrid analysis of a human trabecular meshwork cDNA library identified EFEMP2 as a novel PITX2 interacting protein. Mol Vis 2012; 18:2182-9. [PMID: 22919265 PMCID: PMC3425575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 08/03/2012] [Indexed: 11/05/2022] Open
Abstract
PURPOSE Mutations in the homeobox transcription factor paired-like homeodomain transcription factor 2 (PITX2) cause Axenfeld-Reiger syndrome (ARS), which is associated with anterior segment dysgenesis (ASD) and glaucoma. To understand ARS pathogenesis, it is essential to know the normal functions of PITX2 and the proteins with which PITX2 interacts in the eye. Therefore, we used a unique cDNA library that we created from human trabecular meshwork (TM) primary cells to discover PITX2-interacting proteins (PIPs). METHODS A human TM cDNA library was created from primary cells in the ProQuest Two-Hybrid prey vector: pEXP-AD502. Human PITX2A and PITX2C isoforms were used independently as "bait" to identify novel PIPs. A total of 1.25×10⁶ clones were screened by yeast two-hybrid (Y2H) analyses. PIPs obtained from each Y2H experiment were confirmed by yeast retransformation and mammalian co-immunoprecipitation assays. RESULTS EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2) was identified by both PITX2A and PITX2C isoforms as a novel PIP from Y2H analyses. EFEMP2 is 443 amino acids long with six epidermal growth factor (EGF)-like modules and one fibulin-like module. The PITX2-interaction domain in EFEMP2 lies between the second EGF-like module and the COOH-terminal fibulin-like module. Co-immunoprecipitation assays in COS-7 cells confirmed the interaction between PITX2 and EFEMP2. CONCLUSIONS We discovered EFEMP2 as a novel PITX2-interacting protein. Further, our cDNA library made from human TM primary cells is a unique and effective resource to identify novel interacting proteins for glaucoma and ASD candidates. This resource could be used both for discovery and validation of interactomes identified from in silico analysis.
Collapse
Affiliation(s)
- Moulinath Acharya
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Michael W. Sharp
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Farideh Mirzayans
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Tim Footz
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - LiJia Huang
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Chanchal Birdi
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Michael A. Walter
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
- Department of Ophthalmology, University of Alberta, Edmonton, AB, Canada
| |
Collapse
|
42
|
Li P, Reif R, Zhi Z, Martin E, Shen TT, Johnstone M, Wang RK. Phase-sensitive optical coherence tomography characterization of pulse-induced trabecular meshwork displacement in ex vivo nonhuman primate eyes. J Biomed Opt 2012; 17:076026. [PMID: 22894509 DOI: 10.1117/1.jbo.17.7.076026] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Glaucoma is a blinding disease for which intraocular pressure (IOP) is the only treatable risk factor. The mean IOP is regulated through the aqueous outflow system, which contains the trabecular meshwork (TM). Considerable evidence indicates that trabecular tissue movement regulates the aqueous outflow and becomes abnormal during glaucoma; however, such motion has thus far escaped detection. The purpose of this study is to describe anovel use of a phase-sensitive optical coherence tomography (PhS-OCT) method to assess pulse-dependent TM movement. For this study, we used enucleated monkey eyes, each mounted in an anterior segment holder. A perfusion system was used to control the mean IOP as well as to provide IOP sinusoidal transients (amplitude 3 mmHg, frequency 1 pulse/second) in all experiments. Measurements were carried out at seven graded mean IOPs (5, 8, 10, 20, 30, 40, and 50 mm Hg). We demonstrate that PhS-OCT is sensitive enough to image/visualize TM movement synchronous with the pulse-induced IOP transients, providing quantitative measurements of dynamic parameters such as velocity, displacement, and strain rate that are important for assessing the biomechanical compliance of the TM. We find that the largest TM displacement is in the area closest to Schlemm's canal (SC) endothelium. While maintaining constant ocular pulse amplitude, an increase of mean IOP results in a decrease of TM displacement and mean size of the SC. These results demonstrate that the PhS-OCT is a useful imaging technique capable of assessing functional properties necessary to maintain IOP in a healthy range, offering a new diagnostic alternative for glaucoma.
Collapse
Affiliation(s)
- Peng Li
- University of Washington, Departments of Bioengineering, Seattle, Washington 98195, USA
| | | | | | | | | | | | | |
Collapse
|
43
|
Dibas A, Jiang M, Fudala R, Gryczynski I, Gryczynski Z, Clark AF, Yorio T. Fluorescent protein-labeled glucocorticoid receptor alpha isoform trafficking in cultured human trabecular meshwork cells. Invest Ophthalmol Vis Sci 2012; 53:2938-50. [PMID: 22447868 PMCID: PMC3376074 DOI: 10.1167/iovs.11-8331] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 01/17/2012] [Accepted: 03/14/2012] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To characterize the roles of the cytoskeleton and heat shock protein 90 (HSP90) in steroid-induced glucocorticoid receptor alpha (GRα) translocation in cultured human trabecular meshwork cells. METHODS Stably transfected red fluorescent protein (RFP)-GRα NTM5 cell lines were developed. Nuclear localization of RFP-GRα in NTM5 cells treated with vehicle (ethanol), dexamethasone (DEX), or RU486 was measured in cytosolic and nuclear fractions by western blotting and laser confocal microscopy. Cytochalasin D, colchicine, and 17-demethoxygeldanamycin (17AAG, an HSP90 inhibitor), were tested for their abilities to affect GRα trafficking. Nuclear export of RFP-GRα was studied using confocal microscopy following DEX or RU486 removal. RESULTS NTM5 cells transfected with RFP-GRα showed a clear cytosolic localization of receptor that underwent nuclear localization after DEX treatment. RFP-GRα translocation was temperature sensitive, occurring at 37°C but not at room temperature. Neither cytochalasin D nor colchicine blocked DEX-induced or RU486-induced RFP-GRα nuclear translocation; however, 17AAG prevented DEX-induced RFP-GRα nuclear translocation. Both nuclear import and export of DEX-induced RFP-GRα were faster than RU-486-induced nuclear shuttling. CONCLUSIONS RFP-GRα receptor behaves similarly to the wild-type GRα with its cytosolic localization and shuttling to nucleus after DEX or RU486 treatment. HSP90 is required for nuclear translocation, but the disruption of cytoskeleton had no effect on nuclear translocation of RFP-GRα.
Collapse
Affiliation(s)
- Adnan Dibas
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
| | | | | | | | | | | | | |
Collapse
|
44
|
Porter KM, Epstein DL, Liton PB. Up-regulated expression of extracellular matrix remodeling genes in phagocytically challenged trabecular meshwork cells. PLoS One 2012; 7:e34792. [PMID: 22529935 PMCID: PMC3329506 DOI: 10.1371/journal.pone.0034792] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Accepted: 03/08/2012] [Indexed: 11/18/2022] Open
Abstract
Background Cells in the trabecular meshwork (TM), the tissue responsible for draining aqueous humor out of the eye, are known to be highly phagocytic. Phagocytic function in TM cells is thought to play an important role in the normal functioning of the outflow pathway. Dysfunction of phagocytosis could lead to abnormalities of outflow resistance and increased intraocular pressure (IOP). However, the molecular mechanisms triggered by phagocytosis in TM cells are completely unknown. Methodology/Principal Findings Gene expression profile analysis of human TM cells phagocytically challenged to E. coli or pigment under physiological and oxidative stress environment were performed using Affymetrix U133 plus 2.0 array and analyzed with Genespring GX. Despite the differential biological response elicited by E. coli and pigment particles, a number of genes, including MMP1, MMP3, TNFSF11, DIO2, KYNU, and KCCN2 showed differential expression with both phagocytic ligands in all conditions. Data was confirmed by qPCR in both human and porcine TM cells. Metacore pathway analysis and the usage of recombinant adenovirus encoding the dominant negative mutant of IkB identified NF-κB as a transcription factor mediating the up-regulation of at least MMP1 and MMP3 in TM cells with phagocytosis. In-gel zymography demonstrated increased collagenolytic and caseinolytic activities in the culture media of TM cells challenge to E. coli. In addition, collagenolytic I activity was further confirmed using the self-quenched fluorescent substrate DQ-Collagen I. Conclusions/Significance Here we report for the first time the differential gene expression profile of TM cells phagocytically challenged with either E. coli or pigment. Our data indicate a potential role of phagocytosis in outflow pathway tissue homeostasis through the up-regulation and/or proteolytic activation of extracellular matrix remodeling genes.
Collapse
Affiliation(s)
| | | | - Paloma B. Liton
- Duke University, Department of Ophthalmology, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
45
|
Tourtas T, Birke MT, Kruse FE, Welge-Lüssen UC, Birke K. Preventive effects of omega-3 and omega-6 Fatty acids on peroxide mediated oxidative stress responses in primary human trabecular meshwork cells. PLoS One 2012; 7:e31340. [PMID: 22319624 PMCID: PMC3272013 DOI: 10.1371/journal.pone.0031340] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 01/06/2012] [Indexed: 11/18/2022] Open
Abstract
Pathologic processes in glaucoma include increased apoptosis, accumulation of extracellular material in the trabecular meshwork and optic nerve, condensations of the cytoskeleton and precocious cellular senescence. Oxidative stress was shown to generate these alterations in primary ocular cells. Fatty acids omega-3 and -6 are alleged to constitute a prophylaxis against these deleterious effects. Here, we tested actual preventive effects omega-3 and -6 against peroxide induced stress responses in primary human trabecular meshwork cells. Changes of mitochondrial activity, proliferation, heat shock proteins, extracellular matrix components, and inflammatory markers were evaluated. Alterations of the cytoskeleton were evaluated by phalloidin labeling. Here we report a repressive effect of omega-6 on metabolic activity and proliferation, which was not detected for omega-3. Both agents were able to prevent the anti-proliferative effect of H2O2, but only omega-3 prevented metabolic repression. Expression of heat shock protein 27 was unaltered by both fatty acids, whereas heat shock protein 90 was significantly induced by both. Omega-6 increased fibronectin and connective tissue growth factor synthesis, as well as the amount of secreted fibronectin. Omega-3, instead, induced plasminogen activator inhibitor 1 synthesis. H2O2 further increased fibronectin production in omega-6 supplemented cells, which was not the case in omega-3 treated cells. H2O2 stimulation of plasminogen activator inhibitor 1 and connective tissue growth factor was repressed by both fatty acids. Both fatty acids appeared to abolish H2O2 mediated stimulation of nuclear factor κB and IL-6, but not IL-1α and IL-8. H2O2 induced formation of cross-linked actin networks and stress fibers, which was reduced by preemptive application of omega-3. Omega-6, in contrast, had no protective effect on that, and even seemed to promote condensation. Based on the observed side effects of omega-6, omega-3 appears to be the more beneficial fatty acid in respect of prophylactic intake for prevention of a glaucomatous disease.
Collapse
Affiliation(s)
- Theofilos Tourtas
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Marco T. Birke
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | - Friedrich E. Kruse
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
| | | | - Kerstin Birke
- Department of Ophthalmology, University Hospital Erlangen, Erlangen, Germany
- * E-mail:
| |
Collapse
|
46
|
LI ANG, LEUNG CHITING, PETERSON-YANTORNO KIM, STAMER WDANIEL, MITCHELL CLAIREH, CIVAN MORTIMERM. Mechanisms of ATP release by human trabecular meshwork cells, the enabling step in purinergic regulation of aqueous humor outflow. J Cell Physiol 2012; 227:172-82. [PMID: 21381023 PMCID: PMC3117029 DOI: 10.1002/jcp.22715] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Our guiding hypothesis is that ecto-enzymatic conversion of extracellular ATP to adenosine activates A(1) adenosine receptors, reducing resistance to aqueous humor outflow and intraocular pressure. The initial step in this purinergic regulation is ATP release from outflow-pathway cells by mechanisms unknown. We measured similar ATP release from human explant-derived primary trabecular meshwork (TM) cells (HTM) and a human TM cell line (TM5). Responses to 21 inhibitors indicated that pannexin-1 (PX1) and connexin (Cx) hemichannels and P2X(7) receptors (P2RX(7) ) were comparably important in modulating ATP release induced by hypotonic swelling, whereas vesicular release was insignificant. Consistent with prior studies of PX1 activity in certain other cells, ATP release was lowered by the reducing agent dithiothreitol. Overexpressing PX1 in HEK293T cells promoted, while partial knockdown (KD) in both HEK293T and TM5 cells inhibited hypotonicity-activated ATP release. Additionally, KD reduced the pharmacologically defined contribution of PX1 and enhanced those of Cx and P2RX(7) . ATP release was also triggered by raising intracellular Ca(2+) activity with ionomycin after a prolonged lag time and was unaffected by the PX1 blocker probenecid, but nearly abolished by P2RX(7) antagonists. We conclude that swelling-stimulated ATP release from human TM cells is physiologically mediated by PX1 and Cx hemichannels and P2X(7) receptors, but not by vesicular release. PX1 appears not to be stimulated by intracellular Ca(2+) in TM cells, but can be modulated by oxidation-reduction state. The P2RX(7) -dependent component of swelling-activated release may be mediated by PX1 hemichannels or reflect apoptotic magnification of ATP release, either through itself and/or hemichannels.
Collapse
Affiliation(s)
- ANG LI
- Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - CHI TING LEUNG
- Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - KIM PETERSON-YANTORNO
- Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - W. DANIEL STAMER
- Department of Ophthalmology and Vision Science, University of Arizona, Tucson, AZ
| | - CLAIRE H. MITCHELL
- Department of Anatomy and Cell Biology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA
| | - MORTIMER M. CIVAN
- Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia, PA
- Department of Medicine, School of Medicine, University of Pennsylvania, Philadelphia, PA
| |
Collapse
|
47
|
Yu WY, Sheridan C, Grierson I, Mason S, Kearns V, Lo ACY, Wong D. Progenitors for the corneal endothelium and trabecular meshwork: a potential source for personalized stem cell therapy in corneal endothelial diseases and glaucoma. J Biomed Biotechnol 2011; 2011:412743. [PMID: 22187525 PMCID: PMC3236530 DOI: 10.1155/2011/412743] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 09/08/2011] [Indexed: 12/15/2022] Open
Abstract
Several adult stem cell types have been found in different parts of the eye, including the corneal epithelium, conjunctiva, and retina. In addition to these, there have been accumulating evidence that some stem-like cells reside in the transition area between the peripheral corneal endothelium (CE) and the anterior nonfiltering portion of the trabecular meshwork (TM), which is known as the Schwalbe's Ring region. These stem/progenitor cells may supply new cells for the CE and TM. In fact, the CE and TM share certain similarities in terms of their embryonic origin and proliferative capacity in vivo. In this paper, we discuss the putative stem cell source which has the potential for replacement of lost and nonfunctional cells in CE diseases and glaucoma. The future development of personalized stem cell therapies for the CE and TM may reduce the requirement of corneal grafts and surgical treatments in glaucoma.
Collapse
Affiliation(s)
- Wing Yan Yu
- Eye Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - Carl Sheridan
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, University Clinical Departments Building, The Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Ian Grierson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, University Clinical Departments Building, The Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Sharon Mason
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, University Clinical Departments Building, The Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Victoria Kearns
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, University Clinical Departments Building, The Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Amy Cheuk Yin Lo
- Eye Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
- Research Center of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - David Wong
- Eye Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
- Research Center of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
- St. Paul's Eye Unit, Royal Liverpool University Hospital, Prescot Street, Liverpool L7 8XP, UK
| |
Collapse
|
48
|
Sethi A, Mao W, Wordinger RJ, 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 2011; 52:5240-50. [PMID: 21546528 PMCID: PMC3176072 DOI: 10.1167/iovs.11-7287] [Citation(s) in RCA: 150] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 04/03/2011] [Accepted: 04/05/2011] [Indexed: 01/19/2023] Open
Abstract
PURPOSE The profibrotic cytokine TGFβ is associated with glaucoma and plays an important role in the regulation of extracellular matrix metabolism in the trabecular meshwork (TM). The purpose of this study was to determine whether expression of ECM cross-linking LOX genes is regulated by TGFβ in TM cells. METHODS Expression of the five LOX genes (LOX, LOXL1, LOXL2, LOXL3, and LOXL4) was examined in cultured human TM cells by using RT-PCR, quantitative RT-PCR, and Western immunoblot analysis. TM cells were treated with recombinant TGFβ1, -2, and -3, to determine the effects on LOX and LOXL1 to -4 expression. The TM cells were pretreated with TGFBR inhibitors (LY364947, SB431542), canonical Smad signaling pathway (SIS3 or Smad2, -3, and -4 siRNAs) inhibitors, or inhibitors of the non-Smad signaling pathways (SP600125, SR11302), to identify the signaling pathway(s) involved in TGFβ induction of LOX and LOXL gene and protein expression. A novel LOX activity assay was used to determine the effects of the LOX inhibitor BAPN on tropoelastin cross-linking. RESULTS All five LOX genes (LOX, LOXL1 to -4) were expressed in cultured human TM cells and were induced by all three isoforms of TGFβ. This TGFβ induction of LOX and LOXL expression was blocked by TGFβ inhibitors as well as by inhibitors of the canonical Smad2, -3, and -4 signaling and non-Smad JNK/AP-1 signaling pathways (P < 0.05). CONCLUSIONS Both Smad and non-Smad signaling pathways are involved in TGFβ-mediated LOX induction, suggesting complex regulation of these important extracellular matrix cross-linking enzymes. Increased LOX activity may be at least partially responsible for TGFβ-mediated IOP elevation and increased aqueous humor outflow resistance.
Collapse
Affiliation(s)
- Anirudh Sethi
- From the Department of Cell Biology and Anatomy, North Texas Eye Research Institute (NTERI), University of North Texas Health Science Center, Fort Worth, Texas
| | - Weiming Mao
- From the Department of Cell Biology and Anatomy, North Texas Eye Research Institute (NTERI), University of North Texas Health Science Center, Fort Worth, Texas
| | - Robert J. Wordinger
- From the Department of Cell Biology and Anatomy, North Texas Eye Research Institute (NTERI), University of North Texas Health Science Center, Fort Worth, Texas
| | - Abbot F. Clark
- From the Department of Cell Biology and Anatomy, North Texas Eye Research Institute (NTERI), University of North Texas Health Science Center, Fort Worth, Texas
| |
Collapse
|
49
|
Paylakhi SH, Fan JB, Mehrabian M, Sadeghizadeh M, Yazdani S, Katanforoush A, Kanavi MR, Ronaghi M, Elahi E. Effect of PITX2 knockdown on transcriptome of primary human trabecular meshwork cell cultures. Mol Vis 2011; 17:1209-21. [PMID: 21617755 PMCID: PMC3102028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Accepted: 04/25/2011] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To identify genes whose expressions in primary human trabecular meshwork (TM) cell cultures are affected by the transcription factor pituitary homeobox 2 (PITX2) and to identify genes that may have roles in glaucoma. Known glaucoma causing genes account for disease in a small fraction of patients, and we aimed at identification of other genes that may have subtle and accumulative effects not easily identifiable by a genetic approach. METHODS Expression profiles derived using microarrays were compared between TM control cells and cells treated with PITX2 siRNAs using three protocols so as to minimize false positive and negative results. The first protocol was based on the commonly used B statistic. The second and third protocols were based on fold change in expression. The second protocol used a threshold of at least 2 fold change in expression, whereas the third protocol used ranking in fold change without setting a threshold. The likelihood of a selected gene being a true positive was considered to correlate with the number of protocols by which it was selected. By considering all genes that were selected by at least one protocol, the likelihood of false negatives was expected to decrease. Effects on a subset of selected genes were verified by real time PCR, western blots, and immunocytochemistry. Effects on ALDH1A1, were further pursued because its protein product, aldehyde dehydrogenase 1 family, member A1, has roles in oxidative stress and because oxidative stress is known to be relevant to the etiology of glaucoma. RESULTS The expression level of 41 genes was assessed by to be possibly affected by PITX2 knockdown. Twenty one genes were down-regulated and twenty were upregulated. The expression of five genes was assessed to be altered by all three analysis protocols. The five genes were DIRAS3 (DIRAS family, GTP-binding RAS-like 3), CXCL6 (chemokine (C-X-C motif) ligand 6), SAMD5 (sterile alpha motif domain containing 5), CBFB (core-binding factor, beta subunit), and MEIS2 (meis homeobox 2). Real time PCR experiments verified results on a subset of genes tested. Notably, the results were also confirmed in two independent TMs. Effects on CXCL6 and ALDH1A1 were also confirmed by western blots, and effects on ALDH1A1 were further shown by immunocytochemistry. Data consistent with PITX2 involvement in ALDH1A1 mediated response to oxidative stress were presented. CONCLUSIONS Bioinformatics tools revealed that the genes identified affect functions and pathways relevant to glaucoma. Involvement of PITX2 in expression of some of the genes and in some of the pathways is being reported here for the first time. As many of the genes identified have not been studied vis-à-vis glaucoma, we feel they introduce new candidates for understanding this devastating disease.
Collapse
Affiliation(s)
- Seyed Hassan Paylakhi
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | | | | | - Majid Sadeghizadeh
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran
| | - Shahin Yazdani
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Katanforoush
- Department of Computer Science, Faculty of Mathematics, Shahid Beheshti University G.C., Tehran, Iran
| | - Mozhgan Rezaei Kanavi
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Central Eye Bank of Iran, Tehran, Iran
| | | | - Elahe Elahi
- Department of Biotechnology, University of Tehran, Tehran, Iran
- Department of Biology, University College of Science, University of Tehran, Tehran, Iran
- Center of Excellence in Biomathematics, School of Mathematics, Statistics and Computer Science, College of Science, University of Tehran, Tehran, Iran
| |
Collapse
|
50
|
Peng J, Lei CT, Hu JB, 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 2011; 47:336-341. [PMID: 21612684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
OBJECTIVE To investigate the effect of travoprost on changes of actin cytoskeletal and β-catenin protein in the cultured human trabecular meshwork (HTM) cells treated with dexamethasone (DEX). METHODS It was a control experiment study. The HTM cells were cultured in vitro and divided into control group, DEX (1 × 10(-6) mol/L) group, travoprost (1 × 10(-6) mol/L) group, and DEX (1 × 10(-6) mol/L) plus travoprost (1 × 10(-6) mol/L) group. F-actin in the HTM cells was detected by FITC-phalloidin and observed under a fluorescence microscope. The expression of β-catenin was determined by immunofluorescence and western-blot. Statistical analysis was performed using SPSS13.0 software. The difference of β-catenin expression among groups was analyzed through variance analysis and, further by q test. RESULTS The cultured HTM cells were identified by immunohistochemistry. A reorganization of actin cytoskeletal and a formation of cross linked actin networks (CLANs) were seen in the HTM cells treated with DEX, which were partially reversed by the treatment with DEX plus travoprost. An increase of the expression of β-catenin was discovered in the HTM cells treated with DEX, which was also partially reversed by the treatment with DEX plus travoprost. The amount of β-catenin protein in untreated control group, DEX group, DEX plus travoprost group and travoprost group were 0.84 ± 0.03, 1.65 ± 0.05, 1.21 ± 0.05, and 0.65 ± 0.04, respectively. Expression of β-catenin was significantly (F = 143.07, P < 0.05) different when compared untreated control group with DEX group (q = 15.32, P < 0.05), untreated control group with DEX plus travoprost group (q = 11.40, P < 0.05), DEX group with DEX plus travoprost group (q = 9.38, P < 0.05), DEX group with travoprost group (q = 16.55, P < 0.05), and DEX plus travoprost group with travoprost group (q = 14.31, P < 0.05). No difference was found in untreated control group and travoprost group (q = 2.84, P > 0.05). CONCLUSIONS Our results suggest that reversion of the changes of actin organization and β-catenin by travoparost in the HTM cells treated with DEX may partially elucidate the mechanism of action of increasing outflow by which travoprost reduces intraocular pressure.
Collapse
Affiliation(s)
- Jie Peng
- Department of Ophthalmology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu 610072, China
| | | | | | | |
Collapse
|