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Jia X, Wu J, Chen X, Hou S, Li Y, Zhao L, Zhu Y, Li Z, Deng C, Su W, Zhuo Y. Cell atlas of trabecular meshwork in glaucomatous non-human primates and DEGs related to tissue contract based on single-cell transcriptomics. iScience 2023; 26:108024. [PMID: 37867950 PMCID: PMC10589847 DOI: 10.1016/j.isci.2023.108024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 05/22/2023] [Accepted: 09/19/2023] [Indexed: 10/24/2023] Open
Abstract
As the major channel of aqueous humor outflow, dysfunction of trabecular meshwork (TM) can lead to intraocular pressure elevating, which can trigger primary open-angle glaucoma (POAG). In this study, we use single-cell RNA sequencing (scRNA-seq) technique to build an atlas and further explore the spontaneous POAG and healthy macaques cellular heterogeneity associated with the dysfunction of TM contraction. We built the TM atlas, which identified 14 different cell types. In Beam A, Beam B, Beam C, and smooth muscle cell (SMC) cell types, we first found multiple genes associated with TM contraction (e.g., TPM1, ACTC1, TNNT1), determining their differential expression in the POAG and healthy groups. In addition, the microstructural alterations in TM of POAG non-human primates were observed, which was compact and collapsed. Thus, our study indicated that TPM1 may be a key target for regulating TM structure, contraction function, and resistance of aqueous humor outflow.
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Affiliation(s)
- Xu Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
- The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, China
| | - Jian Wu
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Xiaohong Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Simeng Hou
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
- Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, China
| | - Yangyang Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Ling Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Yingting Zhu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Zhidong Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Caibin Deng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Wenru Su
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
| | - Yehong Zhuo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology Visual Science, Guangzhou, Guangdong, China
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Geng C, Liu S, Wang J, Wang S, Zhang W, Rong H, Cao Y, Wang S, Li Z, Zhang Y. Targeting the cochlin/SFRP1/CaMKII axis in the ocular posterior pole prevents the progression of nonpathologic myopia. Commun Biol 2023; 6:884. [PMID: 37644183 PMCID: PMC10465513 DOI: 10.1038/s42003-023-05267-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 08/21/2023] [Indexed: 08/31/2023] Open
Abstract
Myopia is a major public health issue. However, interventional modalities for nonpathologic myopia are limited due to its complicated pathogenesis and the lack of precise targets. Here, we show that in guinea pig form-deprived myopia (FDM) and lens-induced myopia (LIM) models, the early initiation, phenotypic correlation, and stable maintenance of cochlin protein upregulation at the interface between retinal photoreceptors and retinal pigment epithelium (RPE) is identified by a proteomic analysis of ocular posterior pole tissues. Then, a microarray analysis reveals that cochlin upregulates the expression of the secreted frizzled-related protein 1 (SFRP1) gene in human RPE cells. Moreover, SFRP-1 elevates the intracellular Ca2+ concentration and activates Ca2+/calmodulin-dependent protein kinase II (CaMKII) signaling in a simian choroidal vascular endothelial cell line, and elicits vascular endothelial cell dysfunction. Furthermore, genetic knockdown of the cochlin gene and pharmacological blockade of SFRP1 abrogates the reduced choroidal blood perfusion and prevents myopia progression in the FDM model. Collectively, this study identifies a novel signaling axis that may involve cochlin in the retina, SFRP1 in the RPE, and CaMKII in choroidal vascular endothelial cells and contribute to the pathogenesis of nonpathologic myopia, implicating the potential of cochlin and SFRP1 as myopia interventional targets.
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Affiliation(s)
- Chao Geng
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Siyi Liu
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Jindan Wang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Sennan Wang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Weiran Zhang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Hua Rong
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Yunshan Cao
- Department of Cardiology, Gansu Provincial Hospital, Lanzhou University, 730000, Lanzhou, Gansu Province, China
| | - Shuqing Wang
- School of Pharmacy, Tianjin Medical University, 300070, Tianjin, China
| | - Zhiqing Li
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China
| | - Yan Zhang
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, 300384, Tianjin, China.
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André da Silva R, Moraes de Paiva Roda V, Philipe de Souza Ferreira L, Oliani SM, Paula Girol A, Gil CD. Annexins as potential targets in ocular diseases. Drug Discov Today 2022; 27:103367. [PMID: 36165812 DOI: 10.1016/j.drudis.2022.103367] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 08/05/2022] [Accepted: 09/14/2022] [Indexed: 11/20/2022]
Abstract
Annexins (AnxAs) are Ca2+/phospholipid-binding proteins extensively studied and generally involved in several diseases. Although evidence exists regarding the distribuition of AnxAs in the visual system, their exact roles and the exact cell types of the eye where these proteins are expressed are not well-understood. AnxAs have pro-resolving roles in infectious, autoimmune, degenerative, fibrotic and angiogenic conditions, making them an important target in ocular tissue homeostasis. This review summarizes the current knowledge on the distribution and function of AnxA1-8 isoforms under normal and pathological conditions in the visual system, as well as perspectives for ophthalmologic treatments, including the potential use of the AnxA1 recombinant and/or its mimetic peptide Ac2-26.
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Affiliation(s)
- Rafael André da Silva
- Biosciences Graduate Program, Institute of Biosciences, Letters and Exact Sciences, Universidade Estadual Paulista (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Vinicius Moraes de Paiva Roda
- Life Systems Biology Graduate Program, Institute of Biomedical Sciences, Universidade de São Paulo (USP), São Paulo, SP 05508-000, Brazil
| | - Luiz Philipe de Souza Ferreira
- Structural and Functional Biology Graduate Program, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-900, Brazil
| | - Sonia M Oliani
- Biosciences Graduate Program, Institute of Biosciences, Letters and Exact Sciences, Universidade Estadual Paulista (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Structural and Functional Biology Graduate Program, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-900, Brazil; Advanced Research Center in Medicine (CEPAM) Unilago, São José do Rio Preto, SP 15030-070, Brazil
| | - Ana Paula Girol
- Biosciences Graduate Program, Institute of Biosciences, Letters and Exact Sciences, Universidade Estadual Paulista (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Structural and Functional Biology Graduate Program, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-900, Brazil; Centro Universitário Padre Albino (UNIFIPA), Catanduva, SP 15809-144, Brazil
| | - Cristiane D Gil
- Biosciences Graduate Program, Institute of Biosciences, Letters and Exact Sciences, Universidade Estadual Paulista (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Structural and Functional Biology Graduate Program, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP 04023-900, Brazil.
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4
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Al‐Qahtani SM, Gadalla SE, Guo M, Ericsson C, Hägerstrand D, Nistér M. The association between Annexin A2 and epithelial cell adhesion molecule in breast cancer cells. Cancer Rep (Hoboken) 2022; 5:e1498. [PMID: 34240826 PMCID: PMC9124509 DOI: 10.1002/cnr2.1498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/05/2021] [Accepted: 06/14/2021] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND The epithelial cell adhesion molecule (EpCAM) is a type I transmembrane and glycosylated protein, which is overexpressed in many neoplasms. However, EpCAM has no known ligand partners and the mechanisms by which it functions are not fully understood. AIM This study was performed to discover novel partners of EpCAM, which may provide a better understanding of its functions. METHODS The membrane fraction of the ERα+ noninvasive breast cancer cell line ZR-75-1 and MCF-7 was extracted and followed by co-immunoprecipitation of EpCAM using C-10, a mouse monoclonal antibody raised against amino acids 24-93 of the EpCAM molecule. As a negative control, MDA-MB-231 and Hs578T were used since they express a negligible amount of EpCAM and are known as EpCAM-/low ERα-/low invasive and tumorigenic breast cancer cell lines. RESULTS Annexin A2 (ANXA2) was found to be selectively and differentially co-immunoprecipitated with EpCAM in the ERα+ breast cancer cells MCF-7 and ZR-75-1. ANXA2 is a multifunctional protein and known to act as a co-receptor for tissue plasminogen activator (tPA) on the surface of endothelial and cancer cells, thereby affecting fibrinolytic activity and neoangiogenesis as well as invasive and metastatic properties. In this study, the association between EpCAM and ANXA2 was found to affect the activity of tPA. CONCLUSION This study concludes that ANXA2 co-localizes with EpCAM at the plasma membrane, and the co-localization may have functional implications. Data suggest that EpCAM supports ANXA2 to function as a co-receptor for the tPA, and that EpCAM has a regulatory function on the expression and subcellular localization of ANXA2.
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Affiliation(s)
- Saad Misfer Al‐Qahtani
- Department of Oncology‐PathologyKarolinska InstitutetStockholmSweden
- Department of Pathology, College of Medicine and Najran University HospitalNajran UniversityNajranSaudi Arabia
| | | | - Min Guo
- Department of Oncology‐PathologyKarolinska InstitutetStockholmSweden
| | | | | | - Monica Nistér
- Department of Oncology‐PathologyKarolinska InstitutetStockholmSweden
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5
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Lengyel M, Enyedi P, Czirják G. Negative Influence by the Force: Mechanically Induced Hyperpolarization via K 2P Background Potassium Channels. Int J Mol Sci 2021; 22:ijms22169062. [PMID: 34445768 PMCID: PMC8396510 DOI: 10.3390/ijms22169062] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 02/08/2023] Open
Abstract
The two-pore domain K2P subunits form background (leak) potassium channels, which are characterized by constitutive, although not necessarily constant activity, at all membrane potential values. Among the fifteen pore-forming K2P subunits encoded by the KCNK genes, the three members of the TREK subfamily, TREK-1, TREK-2, and TRAAK are mechanosensitive ion channels. Mechanically induced opening of these channels generally results in outward K+ current under physiological conditions, with consequent hyperpolarization and inhibition of membrane potential-dependent cellular functions. In the past decade, great advances have been made in the investigation of the molecular determinants of mechanosensation, and members of the TREK subfamily have emerged among the best-understood examples of mammalian ion channels directly influenced by the tension of the phospholipid bilayer. In parallel, the crucial contribution of mechano-gated TREK channels to the regulation of membrane potential in several cell types has been reported. In this review, we summarize the general principles underlying the mechanical activation of K2P channels, and focus on the physiological roles of mechanically induced hyperpolarization.
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Abstract
OBJECTIVE In this review the authors discuss evidence from the literature concerning vitamin D and temporal bone diseases (benign paroxysmal positional vertigo [BPPV], Menière's disease [MD], vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss). Common features shared by Menière's disease, glaucoma, and the possible influence by vitamin D are briefly discussed. DATA SOURCES, STUDY SELECTION Publications from 1970 until recent times have been reviewed according to a keyword search (see above) in PubMed. CONCLUSIONS MD, BPPV, vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss may all have several etiological factors, but a common feature of the current theories is that an initial viral infection and a subsequent autoimmune/autoinflammatory reaction might be involved. Additionally, in some of these entities varying degrees of demyelination have been documented. Given the immunomodulatory effect of vitamin D, we postulate that it may play a role in suppressing an eventual postviral autoimmune reaction. This beneficial effect may be enhanced by the antioxidative activity of vitamin D and its potential in stabilizing endothelial cells. The association of vitamin D deficiency with demyelination has already been established in other entities such as multiple sclerosis and experimental autoimmune encephalitis. Mice without vitamin D receptor show degenerative features in inner ear ganglia, hair cells, as well as otoconia. The authors suggest further studies concerning the role of vitamin D deficiency in diseases of the temporal bone. Additionally, the possible presence and degree of demyelination in these entities will have to be elucidated more systematically in the future.
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7
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Edwards G, Arcuri J, Wang H, Ziebarth N, Zode G, Lee RK, Bhattacharya SK. Endogenous ocular lipids as potential modulators of intraocular pressure. J Cell Mol Med 2020; 24:3856-3900. [PMID: 32090468 PMCID: PMC7171415 DOI: 10.1111/jcmm.14975] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/04/2019] [Accepted: 12/21/2019] [Indexed: 12/13/2022] Open
Abstract
Elevated intraocular pressure (IOP) is a risk factor in glaucoma, a group of irreversible blinding diseases. Endogenous lipids may be involved in regulation of IOP homeostasis. We present comparative fold analysis of phospholipids and sphingolipids of aqueous humour and trabecular meshwork from human control vs primary open-angle glaucoma and mouse control (normotensive) vs ocular hypertensive state. The fold analysis in control vs disease state was based on ratiometric mass spectrometric data for above classes of lipids. We standardized in vitro assays for rapid characterization of lipids undergoing significant diminishment in disease state. Evaluation of lipids using in vitro assays helped select a finite number of lipids that may potentially expand cellular interstitial space embedded in an artificial matrix or increase fluid flow across a layer of cells. These assays reduced a number of lipids for initial evaluation using a mouse model, DBA/2J with spontaneous IOP elevation. These lipids were then used in other mouse models for confirmation of IOP lowering potential of a few lipids that were found promising in previous assessments. Our results provide selected lipid molecules that can be pursued for further evaluation and studies that may provide insight into their function.
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Affiliation(s)
- Genea Edwards
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA.,Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL, USA
| | - Jennifer Arcuri
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA
| | - Haiyan Wang
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA.,Shanghai Key Laboratory of Ocular Fundus Diseases, Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Noel Ziebarth
- Department of Biomedical Engineering, University of Miami, Miami, FL, USA
| | - Gulab Zode
- North Texas Eye Research Institute, University of North Texas, Fort Worth, TX, USA
| | - Richard K Lee
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA
| | - Sanjoy K Bhattacharya
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miami, FL, USA.,Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL, USA
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Yarishkin O, Phuong TTT, Križaj D. Trabecular Meshwork TREK-1 Channels Function as Polymodal Integrators of Pressure and pH. Invest Ophthalmol Vis Sci 2019; 60:2294-2303. [PMID: 31117121 PMCID: PMC6532698 DOI: 10.1167/iovs.19-26851] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose The concentration of protons in the aqueous humor (AH) of the vertebrate eye is maintained close to blood pH; however, pathologic conditions and surgery may shift it by orders of magnitude. We investigated whether and how changes in extra- and intracellular pH affect the physiology and function of trabecular meshwork (TM) cells that regulate AH outflow. Methods Electrophysiology, in conjunction with pharmacology, gene knockdown, and optical recording, was used to track the pH dependence of transmembrane currents and mechanotransduction in primary and immortalized human TM cells. Results Extracellular acidification depolarized the resting membrane potential by inhibiting an outward K+-mediated current, whereas alkalinization hyperpolarized the cells and augmented the outward conductance. Intracellular acidification with sodium bicarbonate hyperpolarized TM cells, whereas removal of intracellular protons with ammonium chloride depolarized the membrane potential. The effects of extra- and intracellular acid and alkaline loading were abolished by quinine, a pan-selective inhibitor of two-pore domain potassium (K2P) channels, and suppressed by shRNA-mediated downregulation of the mechanosensitive K2P channel TREK-1. Extracellular acidosis suppressed, whereas alkalosis facilitated, the amplitude of the pressure-evoked TREK-1–mediated outward current. Conclusions These results demonstrate that TM mechanotransduction mediated by TREK-1 channels is profoundly sensitive to extra- and intracellular pH shifts. Intracellular acidification might modulate aqueous outflow and IOP by stimulating TREK-1 channels.
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Affiliation(s)
- Oleg Yarishkin
- Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, Utah, United States
| | - Tam T T Phuong
- Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, Utah, United States
| | - David Križaj
- Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, Utah, United States.,Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah, United States.,Department of Bioengineering, University of Utah, Salt Lake City, Utah, United States
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Sun H, Zhu Q, Guo P, Zhang Y, Tighe S, Zhu Y. Trabecular meshwork cells are a valuable resource for cellular therapy of glaucoma. J Cell Mol Med 2019; 23:1678-1686. [PMID: 30659738 PMCID: PMC6378204 DOI: 10.1111/jcmm.14158] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/15/2018] [Accepted: 12/23/2018] [Indexed: 12/16/2022] Open
Abstract
Trabecular meshwork (TM) contains a subset of adult stem cells or progenitors that can be differentiated into corneal endothelial cells, adipocytes and chondrocytes, but not osteocytes or keratocytes. Accordingly, these progenitors can be utilized as a cell‐based therapy to prevent blindness caused by glaucoma, corneal endothelial dysfunction and other diseases in general. In this review, we review in vitro expansion techniques for TM progenitors, discuss their phenotypic properties, and highlight their potential clinical applications in various ophthalmic diseases.
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Affiliation(s)
- Hong Sun
- Department of Ophthalmology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Qin Zhu
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province (Fourth Affiliated Hospital of Kunming Medical University), Yunnan Eye Institute, Key Laboratory of Yunnan Province for the Prevention and Treatment of Ophthalmology (2017DG008), Provincial Innovation Team for Cataract and Ocular Fundus Disease, The Second People's Hospital of Yunnan Province (2017HC010), Expert Workstation of Yao Ke (2017IC064), Kunming, China
| | - Ping Guo
- Shenzhen University School of Medicine, Shenzhen Eye Hospital, Shenzhen, China
| | - Yuan Zhang
- Tissue Tech, Inc., Ocular Surface Center, Ocular Surface Research & Education Foundation, Miami, Florida
| | - Sean Tighe
- Tissue Tech, Inc., Ocular Surface Center, Ocular Surface Research & Education Foundation, Miami, Florida
| | - Yingting Zhu
- Tissue Tech, Inc., Ocular Surface Center, Ocular Surface Research & Education Foundation, Miami, Florida
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10
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Isolation and Expansion of Multipotent Progenitors from Human Trabecular Meshwork. Sci Rep 2018; 8:2814. [PMID: 29434243 PMCID: PMC5809375 DOI: 10.1038/s41598-018-21098-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/30/2018] [Indexed: 12/13/2022] Open
Abstract
To expand multi-potent progenitors from human trabecular meshwork (TM), we have created a new optimized method on two-dimensional (2D) followed by three-dimensional (3D) Matrigel in modified embryonic stem cell medium supplemented with 5% fetal bovine serum (MESCM + 5% FBS). The expanded TM cells were small cuboidal cells expressing TM markers such as AQP1, MGP, CHI3L1, and AnkG, embryonic stem cell (ESC) markers such as Oct4, Sox2, Nanog, and ABCG2, and neural crest (NC) markers such as p75NTR, FOXD3, Sox9, Sox10, and MSX1. Although expanded cells lost expression of these markers after passage, the cells regained the markers when Passage 2 cells were seeded on 3D Matrigel through activation of canonical BMP signaling. Such restored progenitors could differentiate into corneal endothelial cells, adipocytes, and chondrocytes but not keratocytes or osteocytes. Therefore, we have concluded that human TM harbors multipotent progenitors that can be effectively isolated and expanded using 2D Matrigel in MESCM + 5% FBS. This unique in vitro model system can be used to understand how TM is altered in glaucoma and whether such TM progenitor cells might one day be used for treating glaucoma or corneal endothelial dysfunction.
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Pineda RH, Nedumaran B, Hypolite J, Pan XQ, Wilson S, Meacham RB, Malykhina AP. Altered expression and modulation of the two-pore-domain (K 2P) mechanogated potassium channel TREK-1 in overactive human detrusor. Am J Physiol Renal Physiol 2017; 313:F535-F546. [PMID: 28539337 DOI: 10.1152/ajprenal.00638.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 05/10/2017] [Accepted: 05/18/2017] [Indexed: 01/25/2023] Open
Abstract
Detrusor overactivity (DO) is the abnormal response of the urinary bladder to physiological stretch during the filling phase of the micturition cycle. The mechanisms of bladder smooth muscle compliance upon the wall stretch are poorly understood. We previously reported that the function of normal detrusor is regulated by TREK-1, a member of the mechanogated subfamily of two-pore-domain potassium (K2P) channels. In the present study, we aimed to identify the changes in expression and function of TREK-1 channels under pathological conditions associated with DO, evaluate the potential relationship between TREK-1 channels and cytoskeletal proteins in the human bladder, and test the possibility of modulation of TREK-1 channel expression by small RNAs. Expression of TREK-1 channels in DO specimens was 2.7-fold decreased compared with control bladders and was associated with a significant reduction of the recorded TREK-1 currents. Isolated DO muscle strips failed to relax when exposed to a TREK-1 channel opener. Immunocytochemical labeling revealed close association of TREK-1 channels with cell cytoskeletal proteins and caveolins, with caveolae microdomains being severely disrupted in DO specimens. Small activating RNA (saRNA) tested in vitro provided evidence that expression of TREK-1 protein could be partially upregulated. Our data confirmed a significant downregulation of TREK-1 expression in human DO specimens and provided evidence of close association between the channel, cell cytoskeleton, and caveolins. Upregulation of TREK-1 expression by saRNA could be a future step for the development of in vivo pharmacological and genetic approaches to treat DO in humans.
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Affiliation(s)
- Ricardo H Pineda
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
| | - Balachandar Nedumaran
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
| | - Joseph Hypolite
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
| | - Xiao-Qing Pan
- Division of Urology, Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Shandra Wilson
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
| | - Randall B Meacham
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
| | - Anna P Malykhina
- Division of Urology, Department of Surgery, University of Colorado Denver, Aurora, Colorado; and
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12
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Hirt J, Liton PB. Autophagy and mechanotransduction in outflow pathway cells. Exp Eye Res 2017; 158:146-153. [PMID: 27373974 PMCID: PMC5199638 DOI: 10.1016/j.exer.2016.06.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 06/23/2016] [Accepted: 06/27/2016] [Indexed: 12/19/2022]
Abstract
Because of elevations in IOP and other forces, cells in the trabecular meshwork (TM) are constantly subjected to mechanical strain. In order to preserve cellular function and regain homeostasis, cells must sense and adapt to these morphological changes. We and others have already shown that mechanical stress can trigger a broad range of responses in TM cells; however, very little is known about the strategies that TM cells use to respond to this stress, so they can adapt and survive. Autophagy, a lysosomal degradation pathway, has emerged as an important cellular homeostatic mechanism promoting cell survival and adaptation to a number of cytotoxic stresses. Our laboratory has reported the activation of autophagy in TM cells in response to static biaxial strain and high pressure. Moreover, our newest data also suggest the activation of chaperon-assisted selective autophagy, a recently identified tension-induced autophagy essential for mechanotransduction, in TM cells under cyclic mechanical stress. In this review manuscript we will discuss autophagy as part of an integrated response triggered in TM cells in response to strain, exerting a dual role in repair and mechanotransduction, and the potential effects of dysregulated in outflow pathway pathophysiology.
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Affiliation(s)
- Joshua Hirt
- Duke University, Department of Ophthalmology, Durham, NC, USA
| | - Paloma B Liton
- Duke University, Department of Ophthalmology, Durham, NC, USA.
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13
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Xin C, Wang RK, Song S, Shen T, Wen J, Martin E, Jiang Y, Padilla S, Johnstone M. Aqueous outflow regulation: Optical coherence tomography implicates pressure-dependent tissue motion. Exp Eye Res 2017; 158:171-186. [PMID: 27302601 PMCID: PMC5272871 DOI: 10.1016/j.exer.2016.06.007] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 05/21/2016] [Accepted: 06/09/2016] [Indexed: 12/28/2022]
Abstract
Glaucoma is a leading cause of blindness worldwide and results from damage to the optic nerve. Currently, intraocular pressure is the only treatable risk factor. Changes in aqueous outflow regulate pressure; regulation becomes abnormal in glaucoma. From inside the eye aqueous flows out through the trabecular meshwork into a venous sinus called Schlemm's canal, next into collector channels and finally returns to the episcleral vessels of the venous system. The location of aqueous outflow regulation is unknown. Ex vivo and in vivo studies implicate both pressure-dependent trabecular tissue motion and tissues distal to Schlemm's canal in regulation of aqueous outflow. Technologies have not previously been available to study these issues. New ex vivo imaging in human eyes identifies hinged flaps or leaflets at collector channel entrances using a high-resolution spectral domain optical coherence tomography (SD-OCT) platform. The hinged flaps open and close in synchrony with pressure-dependent trabecular meshwork motion. The SD-OCT platform images from the trabecular meshwork surface while experimentally changing transtrabecular pressure gradients. New in vivo imaging in human eyes uses a motion sensitive technology, phase-sensitive OCT to quantitate real-time pulse-dependent trabecular tissue motion as well as absence of such motion when aqueous access to the outflow system is blocked. The recent studies suggest that aqueous outflow regulation results from synchronous pressure-dependent motion involving a network of interconnected tissues including those distal to Schlemm's canal. The new imaging technologies may shed light on glaucoma mechanisms and provide guidance in the management of medical, laser and surgical decisions in glaucoma.
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Affiliation(s)
- Chen Xin
- Department of Bioengineering, University of Washington, USA; Department of Ophthalmology, Beijing Anzhen Hospital, Capital Medical University, China.
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, USA; Department of Ophthalmology, University of Washington, USA.
| | - Shaozhen Song
- Department of Bioengineering, University of Washington, USA.
| | - Tueng Shen
- Department of Bioengineering, University of Washington, USA; Department of Ophthalmology, University of Washington, USA.
| | - Joanne Wen
- Department of Ophthalmology, University of Washington, USA.
| | | | - Yi Jiang
- Department of Ophthalmology, University of Washington, USA.
| | - Steven Padilla
- Department of Ophthalmology, University of Washington, USA.
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14
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Carreon TA, Edwards G, Wang H, Bhattacharya SK. Segmental outflow of aqueous humor in mouse and human. Exp Eye Res 2017; 158:59-66. [PMID: 27498226 PMCID: PMC5290258 DOI: 10.1016/j.exer.2016.08.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 07/08/2016] [Accepted: 08/01/2016] [Indexed: 12/28/2022]
Abstract
The main and only modifiable risk factor in glaucoma, the group of usually late onset progressive and irreversible blinding optic neuropathies, is elevated intraocular pressure (IOP). The increase in IOP is due to impeded aqueous humor (AH) outflow through the conventional pathway. The aberrant increased resistance at the trabecular meshwork (TM), the filter-like region in the anterior eye chamber is the major contributory factor in causing the impeded outflow. In normal as well as in glaucoma eyes the regions of the TM are divided into areas of high and low flow. The collector channels and distal outflow regions are now increasingly being recognized as potential players in contributing to impede AH outflow. Structural and molecular make-up contributing to the segmental blockage to outflow is likely to provide greater insight. Establishing segmental blockage to outflow in model systems of glaucoma such as the mouse in parallel to human eyes will expand our repertoire of tools for investigation. Further study into this area of interest has the potential to ultimately lead to the development of new therapeutics focused on lowering IOP by targeting the various components of segmental blockage of outflow in the TM and in the distal outflow region.
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Affiliation(s)
- Teresia A Carreon
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL, 33136, USA
| | - Genea Edwards
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL, 33136, USA
| | - Haiyan Wang
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA; Shanghai First People's Hospital Affiliated to Jiaotong University, Shanghai, 200080, China
| | - Sanjoy K Bhattacharya
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA; Department of Biochemistry and Molecular Biology, University of Miami, Miami, FL, 33136, USA.
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15
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Carreon TA, Castellanos A, Gasull X, Bhattacharya SK. Interaction of cochlin and mechanosensitive channel TREK-1 in trabecular meshwork cells influences the regulation of intraocular pressure. Sci Rep 2017; 7:452. [PMID: 28352076 PMCID: PMC5428432 DOI: 10.1038/s41598-017-00430-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 02/28/2017] [Indexed: 12/18/2022] Open
Abstract
In the eye, intraocular pressure (IOP) is tightly regulated and its persistent increase leads to ocular hypertension and glaucoma. We have previously shown that trabecular meshwork (TM) cells might detect aqueous humor fluid shear stress via interaction of the extracellular matrix (ECM) protein cochlin with the cell surface bound and stretch-activated channel TREK-1. We provide evidence here that interaction between both proteins are involved in IOP regulation. Silencing of TREK-1 in mice prevents the previously demonstrated cochlin-overexpression mediated increase in IOP. Biochemical and electrophysiological experiments demonstrate that high shear stress-induced multimeric cochlin produces a qualitatively different interaction with TREK-1 compared to monomeric cochlin. Physiological concentrations of multimeric but not monomeric cochlin reduce TREK-1 current. Results presented here indicate that the interaction of TREK-1 and cochlin play an important role for maintaining IOP homeostasis. [Corrected].
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Affiliation(s)
- Teresia A Carreon
- Bascom Palmer Eye Institute, University of Miami, Miami, Florida, USA.,Department of Biochemistry and Molecular Biology, University of Miami, Miami, USA
| | - Aida Castellanos
- Department of Biomedicine, University of Barcelona, Barcelona, Spain.,Institut d'Investigaciones Biomediques August Pi I Sunyer (IDIBAPS), Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Xavier Gasull
- Department of Biomedicine, University of Barcelona, Barcelona, Spain.,Institut d'Investigaciones Biomediques August Pi I Sunyer (IDIBAPS), Barcelona, Spain.,Institute of Neurosciences, University of Barcelona, Barcelona, Spain
| | - Sanjoy K Bhattacharya
- Bascom Palmer Eye Institute, University of Miami, Miami, Florida, USA. .,Department of Biochemistry and Molecular Biology, University of Miami, Miami, USA.
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16
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Carreon T, van der Merwe E, Fellman RL, Johnstone M, Bhattacharya SK. Aqueous outflow - A continuum from trabecular meshwork to episcleral veins. Prog Retin Eye Res 2017; 57:108-133. [PMID: 28028002 PMCID: PMC5350024 DOI: 10.1016/j.preteyeres.2016.12.004] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 11/14/2016] [Accepted: 12/22/2016] [Indexed: 12/22/2022]
Abstract
In glaucoma, lowered intraocular pressure (IOP) confers neuroprotection. Elevated IOP characterizes glaucoma and arises from impaired aqueous humor (AH) outflow. Increased resistance in the trabecular meshwork (TM), a filter-like structure essential to regulate AH outflow, may result in the impaired outflow. Flow through the 360° circumference of TM structures may be non-uniform, divided into high and low flow regions, termed as segmental. After flowing through the TM, AH enters Schlemm's canal (SC), which expresses both blood and lymphatic markers; AH then passes into collector channel entrances (CCE) along the SC external well. From the CCE, AH enters a deep scleral plexus (DSP) of vessels that typically run parallel to SC. From the DSP, intrascleral collector vessels run radially to the scleral surface to connect with AH containing vessels called aqueous veins to discharge AH to blood-containing episcleral veins. However, the molecular mechanisms that maintain homeostatic properties of endothelial cells along the pathways are not well understood. How these molecular events change during aging and in glaucoma pathology remain unresolved. In this review, we propose mechanistic possibilities to explain the continuum of AH outflow control, which originates at the TM and extends through collector channels to the episcleral veins.
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Affiliation(s)
- Teresia Carreon
- Department of Ophthalmology & Bascom Palmer Eye Institute, University of Miami, Miami, USA; Department of Biochemistry and Molecular Biology, University of Miami, Miami, USA
| | - Elizabeth van der Merwe
- Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Anzio Road, Observatory, 7925 Cape Town, South Africa
| | | | - Murray Johnstone
- Department of Ophthalmology, University of Washington, Seattle, WA, USA
| | - Sanjoy K Bhattacharya
- Department of Ophthalmology & Bascom Palmer Eye Institute, University of Miami, Miami, USA; Department of Biochemistry and Molecular Biology, University of Miami, Miami, USA.
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17
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Giblin JP, Comes N, Strauss O, Gasull X. Ion Channels in the Eye: Involvement in Ocular Pathologies. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 104:157-231. [PMID: 27038375 DOI: 10.1016/bs.apcsb.2015.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The eye is the sensory organ of vision. There, the retina transforms photons into electrical signals that are sent to higher brain areas to produce visual sensations. In the light path to the retina, different types of cells and tissues are involved in maintaining the transparency of avascular structures like the cornea or lens, while others, like the retinal pigment epithelium, have a critical role in the maintenance of photoreceptor function by regenerating the visual pigment. Here, we have reviewed the roles of different ion channels expressed in ocular tissues (cornea, conjunctiva and neurons innervating the ocular surface, lens, retina, retinal pigment epithelium, and the inflow and outflow systems of the aqueous humor) that are involved in ocular disease pathophysiologies and those whose deletion or pharmacological modulation leads to specific diseases of the eye. These include pathologies such as retinitis pigmentosa, macular degeneration, achromatopsia, glaucoma, cataracts, dry eye, or keratoconjunctivitis among others. Several disease-associated ion channels are potential targets for pharmacological intervention or other therapeutic approaches, thus highlighting the importance of these channels in ocular physiology and pathophysiology.
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Affiliation(s)
- Jonathan P Giblin
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Nuria Comes
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Xavier Gasull
- Universitat de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
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18
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Schwingshackl A, Roan E, Teng B, Waters CM. TREK-1 Regulates Cytokine Secretion from Cultured Human Alveolar Epithelial Cells Independently of Cytoskeletal Rearrangements. PLoS One 2015; 10:e0126781. [PMID: 26001192 PMCID: PMC4441361 DOI: 10.1371/journal.pone.0126781] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/28/2015] [Indexed: 01/15/2023] Open
Abstract
Background TREK-1 deficient alveolar epithelial cells (AECs) secrete less IL-6, more MCP-1, and contain less F-actin. Whether these alterations in cytokine secretion and F-actin content are related remains unknown. We now hypothesized that cytokine secretion from TREK-1-deficient AECs was regulated by cytoskeletal rearrangements. Methods We determined F-actin and α-tubulin contents of control, TREK-1-deficient and TREK-1-overexpressing human A549 cells by confocal microscopy and western blotting, and measured IL-6 and MCP-1 levels using real-time PCR and ELISA. Results Cytochalasin D decreased the F-actin content of control cells. Jasplakinolide increased the F-actin content of TREK-1 deficient cells, similar to the effect of TREK-1 overexpression in control cells. Treatment of control and TREK-1 deficient cells with TNF-α, a strong stimulus for IL-6 and MCP-1 secretion, had no effect on F-actin structures. The combination of TNF-α+cytochalasin D or TNF-α+jasplakinolide had no additional effect on the F-actin content or architecture when compared to cytochalasin D or jasplakinolide alone. Although TREK-1 deficient AECs contained less F-actin at baseline, quantified biochemically, they contained more α-tubulin. Exposure to nocodazole disrupted α-tubulin filaments in control and TREK-1 deficient cells, but left the overall amount of α-tubulin unchanged. Although TNF-α had no effect on the F-actin or α-tubulin contents, it increased IL-6 and MCP-1 production and secretion from control and TREK-1 deficient cells. IL-6 and MCP-1 secretions from control and TREK-1 deficient cells after TNF-α+jasplakinolide or TNF-α+nocodazole treatment was similar to the effect of TNF-α alone. Interestingly, cytochalasin D decreased TNF-α-induced IL-6 but not MCP-1 secretion from control but not TREK-1 deficient cells. Conclusion Although cytochalasin D, jasplakinolide and nocodazole altered the F-actin and α-tubulin structures of control and TREK-1 deficient AEC, the changes in cytokine secretion from TREK-1 deficient cells cannot be explained by cytoskeletal rearrangements in these cells.
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Affiliation(s)
- Andreas Schwingshackl
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, United States of America
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, United States of America
- * E-mail:
| | - Esra Roan
- Department of Biomedical Engineering, University of Memphis, Memphis, TN, United States of America
| | - Bin Teng
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, United States of America
| | - Christopher M. Waters
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, United States of America
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States of America
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19
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Edwards G, Aribindi K, Guerra Y, Bhattacharya SK. Sphingolipids and ceramides of mouse aqueous humor: Comparative profiles from normotensive and hypertensive DBA/2J mice. Biochimie 2014; 105:99-109. [PMID: 25014247 DOI: 10.1016/j.biochi.2014.06.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 06/25/2014] [Indexed: 11/17/2022]
Abstract
PURPOSE To identify the sphingolipid and ceramide species and their quantitative differences between normotensive and hypertensive intraocular pressure states in DBA/2J mouse aqueous humor (AH). METHODS Normotensive and hypertensive AH was sampled from mice by paracentesis. Lipid extraction was performed using modifications of the Bligh and Dyer method. Protein concentration was estimated using the Bradford colorimetric assay. Sphingolipids and ceramides were identified and subjected to ratiometric quantification using appropriate class specific lipid standards on a TSQ Quantum Access Max triple quadrupole mass spectrometer. RESULTS The comparative profiles of normotensive and hypertensive DBA/2J mouse AH showed several species of sphingomyelin, sphingoid base, sphingoid base-1-phosphate (S1P) and ceramides common between them. A number of unique lipids in each of the above lipid classes were also identified in normotensive AH that were absent in hypertensive AH and vice versa. CONCLUSION A number of sphingolipid and ceramide species were found to be uniquely present in normotensive, but absent in hypertensive AH and vice versa. Further pursuit of these findings is likely to contribute towards expanding our understanding of the molecular changes associated with increased intraocular pressure (IOP) and glaucoma.
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Affiliation(s)
- Genea Edwards
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA
| | - Katyayini Aribindi
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA
| | - Yenifer Guerra
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA
| | - Sanjoy K Bhattacharya
- Bascom Palmer Eye Institute, University of Miami School of Medicine, Miami, FL 33136, USA.
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20
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Murphy KC, Morgan JT, Wood JA, Sadeli A, Murphy CJ, Russell P. The formation of cortical actin arrays in human trabecular meshwork cells in response to cytoskeletal disruption. Exp Cell Res 2014; 328:164-171. [PMID: 24992043 DOI: 10.1016/j.yexcr.2014.06.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/18/2014] [Accepted: 06/19/2014] [Indexed: 10/25/2022]
Abstract
The cytoskeleton of human trabecular meshwork (HTM) cells is known to be altered in glaucoma and has been hypothesized to reduce outflow facility through contracting the HTM tissue. Latrunculin B (Lat-B) and Rho-associated protein kinase (ROCK) inhibitors disrupt the actin cytoskeleton and are in clinical trials as glaucoma therapeutics. We have previously reported a transient increase in HTM cell stiffness peaking at 90 min after Lat-B treatment with a return to pretreatment values after 270 min. We hypothesize that changes in actin morphology correlate with alterations in cell stiffness induced by Lat-B but this is not a general consequence of other cytoskeletal disrupting agents such as Rho kinase inhibitors. We treated HTM cells with 2 µM Lat-B or 100 µM Y-27632 and allowed the cells to recover for 30-270 min. While examining actin morphology in Lat-B treated cells, we observed striking cortical actin arrays (CAAs). The percentage of CAA positive cells (CPCs) was time dependent and exceeded 30% at 90 min and decreased after 270 min. Y-27632 treated cells exhibited few CAAs and no changes in cell stiffness. Together, these data suggest that the increase in cell stiffness after Lat-B treatment is correlated with CAAs.
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Affiliation(s)
- Kaitlin C Murphy
- Department of Biomedical Engineering / University of California, Davis
| | - Joshua T Morgan
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis
| | - Joshua A Wood
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis
| | - Adeline Sadeli
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis
| | - Christopher J Murphy
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis.,Department of Ophthalmology & Vision Science, School of Medicine / University of California, Davis
| | - Paul Russell
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine / University of California, Davis
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21
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Roan E, Waters CM, Teng B, Ghosh M, Schwingshackl A. The 2-pore domain potassium channel TREK-1 regulates stretch-induced detachment of alveolar epithelial cells. PLoS One 2014; 9:e89429. [PMID: 24586773 PMCID: PMC3929719 DOI: 10.1371/journal.pone.0089429] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 01/22/2014] [Indexed: 12/20/2022] Open
Abstract
Acute Respiratory Distress Syndrome remains challenging partially because the underlying mechanisms are poorly understood. While inflammation and loss of barrier function are associated with disease progression, our understanding of the biophysical mechanisms associated with ventilator-associated lung injury is incomplete. In this line of thinking, we recently showed that changes in the F-actin content and deformability of AECs lead to cell detachment with mechanical stretch. Elsewhere, we discovered that cytokine secretion and proliferation were regulated in part by the stretch-activated 2-pore domain K+ (K2P) channel TREK-1 in alveolar epithelial cells (AECs). As such, the aim of the current study was to determine whether TREK-1 regulated the mechanobiology of AECs through cytoskeletal remodeling and cell detachment. Using a TREK-1-deficient human AEC line (A549), we examined the cytoskeleton by confocal microscopy and quantified differences in the F-actin content. We used nano-indentation with an atomic force microscope to measure the deformability of cells and detachment assays to quantify the level of injury in our monolayers. We found a decrease in F-actin and an increase in deformability in TREK-1 deficient cells compared to control cells. Although total vinculin and focal adhesion kinase (FAK) levels remained unchanged, focal adhesions appeared to be less prominent and phosphorylation of FAK at the Tyr925 residue was greater in TREK-1 deficient cells. TREK-1 deficient cells have less F-actin and are more deformable making them more resistant to stretch-induced injury.
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Affiliation(s)
- Esra Roan
- Department of Biomedical Engineering, University of Memphis, Memphis, Tennessee, United States of America
- * E-mail:
| | - Christopher M. Waters
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Bin Teng
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Manik Ghosh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Andreas Schwingshackl
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
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22
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Tran VT, Ho PT, Cabrera L, Torres JE, Bhattacharya SK. Mechanotransduction channels of the trabecular meshwork. Curr Eye Res 2013; 39:291-303. [PMID: 24215462 DOI: 10.3109/02713683.2013.842593] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE To determine whether the trabecular meshwork (TM), like the other organs engaged in filter like activities (such as kidneys), show the expression of known mechanotransduction channels at protein level. METHODS Human donor eye globes (n = 20), Donor eye derived TM tissue and primary TM cells were utilized for these studies. Commercially available antibodies to channels, immunohisto- and immunocytochemistry, Western blot and mass spectrometric analyses were performed to determine the presence of mechanosensitive channels at protein level. The study was performed adhering to tenets of declaration of Helsinki. RESULTS We demonstrate here the presence of 11 mechanotransduction channels (Piezo1, Piezo2, TASK1, TREK1, TRPA1, TRPC1, TRPC2, TRPC3, TRPC6, TRPM2, TRPP2) as expressed protein in the TM tissue and at the isolated TM cell level. Presence of at least one known isoform of these channels was demonstrated using Western blot analyses. CONCLUSIONS We demonstrated the presence of 11 mechanotransduction channels in the TM and in isolated TM cells at protein level. Demonstration of these channels as proteins at tissue and cellular level will pave the way for further experimentation.
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Affiliation(s)
- Vu T Tran
- Bascom Palmer Eye Institute, University of Miami , Miami, FL , USA
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23
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Jeon YR, Kim SY, Lee EJ, Kim YN, Noh DY, Park SY, Moon A. Identification of annexin II as a novel secretory biomarker for breast cancer. Proteomics 2013; 13:3145-56. [PMID: 24019232 DOI: 10.1002/pmic.201300127] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 08/09/2013] [Accepted: 08/12/2013] [Indexed: 12/15/2022]
Abstract
Early prediction of metastatic breast cancer is important for improvement of prognosis and survival rate. The present study aimed to identify secreted protein biomarkers for detection of invasive breast cancer. To this end, we performed a comparative proteomic analysis by a combination of 2DE and MALDI-TOF MS analysis of conditioned media from invasive H-Ras MCF10A human breast epithelial cells and noninvasive MCF10A and N-Ras MCF10A cells. We identified a list of 25 proteins that were strongly detected in media of H-Ras MCF10A and focused on annexin II, which was shown to be involved in cell motility. Invasive triple-negative human breast carcinoma cells, Hs578T, and MDA-MB-231, showed increased levels of annexin II in media, demonstrating that secretion of annexin II correlated well with the invasive phenotype of cells. We demonstrated a crucial role of annexin II in breast cell invasion/migration and actin cytoskeleton reorganization required for filopodia formation. Annexin II levels in the plasma samples and breast cancer tissues of breast cancer patients were significantly higher than those of normal groups, providing a clinical relevance to our in vitro findings. Taken together, we identified annexin II as a novel secretory biomarker candidate for invasive breast cancer, especially estrogen receptor-negative breast cancer.
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Affiliation(s)
- You Rim Jeon
- College of Pharmacy, Duksung Women's University, Seoul, Korea
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24
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Sphingolipids and ceramides in human aqueous humor. Mol Vis 2013; 19:1966-84. [PMID: 24068864 PMCID: PMC3782370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 09/17/2013] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To determine the differential profiles of sphingomyelin, sphingoid base, sphingoid base-1-phosphate and ceramide lipid species and their quantitative differences between control and glaucomatous aqueous humor (AQH) derived from human donors. METHODS AQH from control and primary open-angle glaucoma donors was collected and subjected to lipid extraction using suitable modifications of the Bligh and Dyer method. Proteins were estimated using Bradford's method. Lipids were identified and ratiometrically quantified in a two-step process using precursor ion scan or neutral loss scan (NLS) with appropriate class-specific lipid standards on a TSQ Quantum Access Max mass spectrometer following established procedures. Primary human trabecular meshwork cells and video microscopic imaging were used to assess changes in cell shape and motility upon exposure to 20 pmol of Cer(d18:0/18:1(9Z)) in 10% dimethyl sulfoxide (vehicle). RESULTS We identified several species of sphingomyelin, sphingoid base, sphingoid base-1-phosphate, and ceramides that were common between control and glaucomatous AQH. Some unique lipid species in these classes were also identified in controls but not in glaucoma and vice versa. We found exposure to 20 pmol of Cer(d18:0/18:1(9Z)) resulted in changes in the trabecular meshwork cell shape and observed motility changes compared to vehicle-only control. CONCLUSIONS Most lipids belonging to the sphingomyelin, sphingoid base, sphingoid base-1-phosphate, and ceramide species were common between control and primary open-angle glaucoma donors. However, some sphingolipids and ceramides were found to be uniquely present in control but absent in the glaucomatous AQH and vice versa. Identification of unique lipid species present or absent in the pathophysiological context may contribute further insight into glaucoma pathology.
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25
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New therapeutic targets for intraocular pressure lowering. ISRN OPHTHALMOLOGY 2013; 2013:261386. [PMID: 24558600 PMCID: PMC3914177 DOI: 10.1155/2013/261386] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 05/30/2013] [Indexed: 01/08/2023]
Abstract
Primary open-angle glaucoma (POAG) is a leading cause of irreversible and preventable blindness and ocular hypertension is the strongest known risk factor. With current classes of drugs, management of the disease focuses on lowering intraocular pressure (IOP). Despite of their use to modify the course of the disease, none of the current medications for POAG is able to reduce the IOP by more than 25%-30%. Also, some glaucoma patients show disease progression despite of the therapeutics. This paper examines the new described physiological targets for reducing the IOP. The main cause of elevated IOP in POAG is thought to be an increased outflow resistance via the pressure-dependent trabecular outflow system, so there is a crescent interest in increasing trabecular meshwork outflow by extracellular matrix remodeling and/or by modulation of contractility/TM cytoskeleton disruption. Modulation of new agents that act mainly on trabecular meshwork outflow may be the future hypotensive treatment for glaucoma patients. There are also other agents in which modulation may decrease aqueous humour production or increase uveoscleral outflow by different mechanisms from those drugs available for glaucoma treatment. Recently, a role for the ghrelin-GHSR system in the pathophysiology modulation of the anterior segment, particularly regarding glaucoma, has been proposed.
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Aribindi K, Guerra Y, Piqueras MDC, Banta JT, Lee RK, Bhattacharya SK. Cholesterol and glycosphingolipids of human trabecular meshwork and aqueous humor: comparative profiles from control and glaucomatous donors. Curr Eye Res 2013; 38:1017-26. [PMID: 23790057 DOI: 10.3109/02713683.2013.803123] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To determine the differential profiles of cholesterol and glycosphingolipid species and their quantitative differences between control and glaucomatous aqueous humor (AQH) and the trabecular meshwork (TM) derived from human donors. METHODS Control TM and selected primary open angle glaucoma (POAG) TM samples were collected from cadaveric donors. Other TM samples, glaucomatous AQH and control AQH were procured during intraocular surgery. Lipid extraction was performed using modifications of the Bligh and Dyer method. Protein concentration was estimated using the Bradford colorimetric assay. Cholesterol and glycosphingolipids were identified and subjected to ratiometric quantification utilizing precursor ion scan and neutral ion loss scan in positive ion mode using appropriate class specific lipid standards (Cholesterol and Psychosine) on a TSQ Quantum Access Max mass spectrometer. RESULTS Control and glaucomatous AQH demonstrated 7 and 4 unique cholesterol species, whereas the TM demonstrated 7 and 12 unique species, respectively. The control and POAG AQH showed 6 and 0 whereas TM samples showed 5 and 1 unique glycosphingolipids, respectively. A total of 65 and 62 common cholesterol species and 59 and 58 common glycosphingolipids were found in AQH and TM, respectively. Increased zymosterol and glucopyranosyl cholesterol levels were found in glaucomatous AQH. Significantly decreased levels of galactosylceramide, glucosylceramide in glaucomatous TM were found compared to control TM. CONCLUSION A high percentage of cholesterol and glycosphingolipid species was found to be common between control and POAG AQH and TM. Several cholesterol and glycosphingolipid species was found to be unique in a subset of POAG or controls. Glaucomatous aqueous humor and TM showed relatively higher levels of zymosterol (an intermediate precursor of cholesterol) and decreased glycoceramide levels, respectively.
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Goel M, Sienkiewicz AE, Picciani R, Wang J, Lee RK, Bhattacharya SK. Cochlin, intraocular pressure regulation and mechanosensing. PLoS One 2012; 7:e34309. [PMID: 22496787 PMCID: PMC3319572 DOI: 10.1371/journal.pone.0034309] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 02/25/2012] [Indexed: 01/06/2023] Open
Abstract
Fluid shear modulates many biological properties. How shear mechanosensing occurs in the extracellular matrix (ECM) and is transduced into cytoskeletal change remains unknown. Cochlin is an ECM protein of unknown function. Our investigation using a comprehensive spectrum of cutting-edge techniques has resulted in following major findings: (1) over-expression and down-regulation of cochlin increase and decrease intraocular pressure (IOP), respectively. The overexpression was achieved in DBA/2J-Gpnmb+/SjJ using lentiviral vectors, down-regulation was achieved in glaucomatous DBA/2J mice using targeted disruption (cochlin-null mice) and also using lentiviral vector mediated shRNA against cochlin coding region; (2) reintroduction of cochlin in cochlin-null mice increases IOP; (3) injection of exogenous cochlin also increased IOP; (4) increasing perfusion rates increased cochlin multimerization, which reduced the rate of cochlin proteolysis by trypsin and proteinase K; The cochlin multimerization in response to shear stress suggests its potential mechanosensing. Taken together with previous studies, we show cochlin is involved in regulation of intraocular pressure in DBA/2J potentially through mechanosensing of the shear stress.
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Affiliation(s)
| | | | | | | | | | - Sanjoy K. Bhattacharya
- Bascom Palmer Eye Institute, University of Miami, Miami, Florida, United States of America
- * E-mail:
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