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Buffault J, Reboussin É, Blond F, Guillonneau X, Bastelica P, Kessal K, Akkurt Arslan M, Melik-Parsadaniantz S, Réaux-le Goazigo A, Labbé A, Brignole-Baudouin F, Baudouin C. RNA-seq transcriptomic profiling of TGF-β2-exposed human trabecular meshwork explants: Advancing insights beyond conventional cell culture models. Exp Cell Res 2024; 442:114220. [PMID: 39214330 DOI: 10.1016/j.yexcr.2024.114220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2024] [Revised: 07/26/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024]
Abstract
Primary open-angle glaucoma (POAG), a leading cause of irreversible vision loss, is closely linked to increased intraocular pressure (IOP), with the trabecular meshwork (TM) playing a critical role in its regulation. The TM, located at the iridocorneal angle, acts as a sieve, filtering the aqueous humor from the eye into the collecting ducts, thus maintaining proper IOP levels. The transforming growth factor-beta 2 (TGF-β2) signaling pathway has been implicated in the pathophysiology of primary open-angle glaucoma POAG particularly, in the dysfunction of the TM. This study utilizes human TM explants to closely mimic in vivo conditions, thereby minimizing transcriptional changes that could arise from cell culture enabling an exploration of the transcriptomic impacts of TGF-β2. Through bulk RNA sequencing and immunohistological analysis, we identified distinct gene expression patterns and morphological changes induced by TGF-β2 exposure (5 ng/ml for 48 h). Bulk RNA sequencing identified significant upregulation in genes linked to extracellular matrix (ECM) regulation and fibrotic signaling. Immunohistological analysis further elucidated the morphological alterations, including cytoskeletal rearrangements and ECM deposition, providing a visual confirmation of the transcriptomic data. Notably, the enrichment analysis unveils TGF-β2's influence on both bone morphogenic protein (BMP) and Wnt signaling pathways, suggesting a complex interplay of molecular mechanisms contributing to TM dysfunction in glaucoma. This characterization of the transcriptomic modifications on an explant model of TM obtained under the effect of this profibrotic cytokine involved in glaucoma is crucial in order to develop and test new molecules that can block their signaling pathways.
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Affiliation(s)
- J Buffault
- Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, IHU Foresight, Paris, France; Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France; Department of Ophthalmology, Ambroise Paré Hospital, APHP, Université de Paris Saclay, Boulogne-Billancourt, France.
| | - É Reboussin
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - F Blond
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - X Guillonneau
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - P Bastelica
- Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, IHU Foresight, Paris, France; Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - K Kessal
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - M Akkurt Arslan
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - S Melik-Parsadaniantz
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - A Réaux-le Goazigo
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France
| | - A Labbé
- Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, IHU Foresight, Paris, France; Department of Ophthalmology, Ambroise Paré Hospital, APHP, Université de Paris Saclay, Boulogne-Billancourt, France
| | - F Brignole-Baudouin
- Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France; Department of Biology, CHNO des Quinze-Vingts, IHU Foresight, Paris, France
| | - C Baudouin
- Department of Ophthalmology III, Quinze-Vingts National Ophthalmology Hospital, IHU Foresight, Paris, France; Sorbonne Université, INSERM, CNRS, IHU Foresight, Institut de La Vision, Paris, France.
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2
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Shui YB, Liu Y, Huang AJW, Siegfried CJ. SDPR expression in human trabecular meshwork and its potential role in racial disparities of glaucoma. Sci Rep 2024; 14:10258. [PMID: 38704467 PMCID: PMC11069504 DOI: 10.1038/s41598-024-61071-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 04/30/2024] [Indexed: 05/06/2024] Open
Abstract
In order to identify how differential gene expression in the trabecular meshwork (TM) contributes to racial disparities of caveolar protein expression, TM dysfunction and development of primary open angle glaucoma (POAG), RNA sequencing was performed to compare TM tissue obtained from White and Black POAG surgical (trabeculectomy) specimens. Healthy donor TM tissue from White and Black donors was analyzed by PCR, qPCR, immunohistochemistry staining, and Western blot to evaluate SDPR (serum deprivation protein response; Cavin 2) and CAV1/CAV2 (Caveolin 1/Caveolin 2). Standard transmission electron microscopy (TEM) and immunogold labeled studies were performed. RNA sequencing demonstrated reduced SDPR expression in TM from Black vs White POAG patients' surgical specimens, with no significant expression differences in other caveolae-associated genes, confirmed by qPCR analysis. No racial differences in SDPR gene expression were noted in healthy donor tissue by PCR analysis, but there was greater expression as compared to specimens from patients with glaucoma. Analysis of SDPR protein expression confirmed specific expression in the TM regions, but not in adjacent tissues. TEM studies of TM specimens from healthy donors did not demonstrate any racial differences in caveolar morphology, but a significant reduction of caveolae with normal morphology and immuno-gold staining of SDPR were noted in glaucomatous TM as compared to TM from healthy donors. Linkage of SDPR expression levels in TM, POAG development, and caveolar ultrastructural morphology may provide the basis for a novel pathway of exploration of the pathologic mechanisms of glaucoma. Differential gene expression of SDPR in TM from Black vs White subjects with glaucoma may further our understanding of the important public health implications of the racial disparities of this blinding disease.
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Affiliation(s)
- Ying-Bo Shui
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Ying Liu
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Andrew J W Huang
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Carla J Siegfried
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, 63110, USA.
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3
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Benedé-Ubieto R, Cubero FJ, Nevzorova YA. Breaking the barriers: the role of gut homeostasis in Metabolic-Associated Steatotic Liver Disease (MASLD). Gut Microbes 2024; 16:2331460. [PMID: 38512763 PMCID: PMC10962615 DOI: 10.1080/19490976.2024.2331460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 03/13/2024] [Indexed: 03/23/2024] Open
Abstract
Obesity, insulin resistance (IR), and the gut microbiome intricately interplay in Metabolic-associated Steatotic Liver Disease (MASLD), previously known as Non-Alcoholic Fatty Liver Disease (NAFLD), a growing health concern. The complex progression of MASLD extends beyond the liver, driven by "gut-liver axis," where diet, genetics, and gut-liver interactions influence disease development. The pathophysiology of MASLD involves excessive liver fat accumulation, hepatocyte dysfunction, inflammation, and fibrosis, with subsequent risk of hepatocellular carcinoma (HCC). The gut, a tripartite barrier, with mechanical, immune, and microbial components, engages in a constant communication with the liver. Recent evidence links dysbiosis and disrupted barriers to systemic inflammation and disease progression. Toll-like receptors (TLRs) mediate immunological crosstalk between the gut and liver, recognizing microbial structures and triggering immune responses. The "multiple hit model" of MASLD development involves factors like fat accumulation, insulin resistance, gut dysbiosis, and genetics/environmental elements disrupting the gut-liver axis, leading to impaired intestinal barrier function and increased gut permeability. Clinical management strategies encompass dietary interventions, physical exercise, pharmacotherapy targeting bile acid (BA) metabolism, and microbiome modulation approaches through prebiotics, probiotics, symbiotics, and fecal microbiota transplantation (FMT). This review underscores the complex interactions between diet, metabolism, microbiome, and their impact on MASLD pathophysiology and therapeutic prospects.
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Affiliation(s)
- Raquel Benedé-Ubieto
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine, Madrid, Spain
| | - Francisco Javier Cubero
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
| | - Yulia A. Nevzorova
- Department of Immunology, Ophthalmology and ENT, Complutense University School of Medicine, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain
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4
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Agarwal R, Iezhitsa I. Genetic rodent models of glaucoma in representing disease phenotype and insights into the pathogenesis. Mol Aspects Med 2023; 94:101228. [PMID: 38016252 DOI: 10.1016/j.mam.2023.101228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/31/2023] [Accepted: 11/11/2023] [Indexed: 11/30/2023]
Abstract
Genetic rodent models are widely used in glaucoma related research. With vast amount of information revealed by human studies about genetic correlations with glaucoma, use of these models is relevant and required. In this review, we discuss the glaucoma endophenotypes and importance of their representation in an experimental animal model. Mice and rats are the most popular animal species used as genetic models due to ease of genetic manipulations in these animal species as well as the availability of their genomic information. With technological advances, induction of glaucoma related genetic mutations commonly observed in human is possible to achieve in rodents in a desirable manner. This approach helps to study the pathobiology of the disease process with the background of genetic abnormalities, reveals potential therapeutic targets and gives an opportunity to test newer therapeutic options. Various genetic manipulation leading to appearance of human relevant endophenotypes in rodents indicate their relevance in glaucoma pathology and the utility of these rodent models for exploring various aspects of the disease related to targeted mutation. The molecular pathways involved in the pathophysiology of glaucoma leading to elevated intraocular pressure and the disease hallmark, apoptosis of retinal ganglion cells and optic nerve degeneration, have been extensively explored in genetic rodent models. In this review, we discuss the consequences of various genetic manipulations based on the primary site of pathology in the anterior or the posterior segment. We discuss how these genetic manipulations produce features in rodents that can be considered a close representation of disease phenotype in human. We also highlight several molecular mechanisms revealed by using genetic rodent models of glaucoma including those involved in increased aqueous outflow resistance, loss of retinal ganglion cells and optic neuropathy. Lastly, we discuss the limitations of the use of genetic rodent models in glaucoma related research.
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Affiliation(s)
- Renu Agarwal
- School of Medicine, International Medical University, Malaysia.
| | - Igor Iezhitsa
- School of Medicine, International Medical University, Malaysia
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5
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Iwagawa T, Saita K, Sagara H, Watanabe S. Downregulation of VEGF in the retinal pigment epithelium followed by choriocapillaris atrophy after NaIO3 treatment in mice. Exp Eye Res 2023; 234:109598. [PMID: 37479076 DOI: 10.1016/j.exer.2023.109598] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 07/09/2023] [Accepted: 07/18/2023] [Indexed: 07/23/2023]
Abstract
Sodium iodate (NaIO3) induces retinal pigment epithelium (RPE) dysfunction, which leads to photoreceptor degeneration. Previously, we used electron microscopy to show that the administration of NaIO3 resulted in the accumulation of cell debris in the subretinal space, which was thought to be caused by failed phagocytosis in the outer segment of the photoreceptor due to RPE dysfunction. We further analyzed the pathological changes in the retina and choroid of NaIO3-injected mice, and found that the expression of OTX2, an RPE marker, disappeared from central part of the RPE 1 day after NaIO3 administration. Furthermore, fenestrated capillaries (choriocapillaris, CC) adjacent to the RPE could not be identified only 2 days after NaIO3 administration. An examination of the expression of the CC-specific protein plasmalemma vesicle-associated protein (PLVAP), in sections and flat-mount retina/choroid specimens showed destruction of the CC, and complete disappearance of the PLVAP signal 7 days after NaIO3 administration. In contrast, CD31 flat-mount immunohistochemistry of the retina indicated no difference in retinal vessels between NaIO3-treated mice and controls. Electron microscopy showed that the fenestrated capillaries in the kidney and duodenum were morphologically indistinguishable between control and NaIO3-treated mice. We examined cytokine production in the retina and RPE, and found that the Vegfa transcript level in the RPE decreased starting 1 day after NaIO3 administration. Taken together, these observations show that NaIO3 reduces the CC in the early stages of the pathology, which is accompanied by a rapid decrease in Vegfa expression in the RPE.
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Affiliation(s)
- Toshiro Iwagawa
- Department of Retinal Biology and Pathology, Graduate School of Medicine, The University of Tokyo, Japan
| | - Kosuke Saita
- Department of Retinal Biology and Pathology, Graduate School of Medicine, The University of Tokyo, Japan; Department of Anesthesiology, Graduate School of Medicine, The University of Tokyo, Japan
| | - Hiroshi Sagara
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Japan
| | - Sumiko Watanabe
- Department of Retinal Biology and Pathology, Graduate School of Medicine, The University of Tokyo, Japan.
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6
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Enyong EN, Gurley JM, De Ieso ML, Stamer WD, Elliott MH. Caveolar and non-Caveolar Caveolin-1 in ocular homeostasis and disease. Prog Retin Eye Res 2022; 91:101094. [PMID: 35729002 PMCID: PMC9669151 DOI: 10.1016/j.preteyeres.2022.101094] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/03/2022] [Accepted: 06/10/2022] [Indexed: 11/17/2022]
Abstract
Caveolae, specialized plasma membrane invaginations present in most cell types, play important roles in multiple cellular processes including cell signaling, lipid uptake and metabolism, endocytosis and mechanotransduction. They are found in almost all cell types but most abundant in endothelial cells, adipocytes and fibroblasts. Caveolin-1 (Cav1), the signature structural protein of caveolae was the first protein associated with caveolae, and in association with Cavin1/PTRF is required for caveolae formation. Genetic ablation of either Cav1 or Cavin1/PTRF downregulates expression of the other resulting in loss of caveolae. Studies using Cav1-deficient mouse models have implicated caveolae with human diseases such as cardiomyopathies, lipodystrophies, diabetes and muscular dystrophies. While caveolins and caveolae are extensively studied in extra-ocular settings, their contributions to ocular function and disease pathogenesis are just beginning to be appreciated. Several putative caveolin/caveolae functions are relevant to the eye and Cav1 is highly expressed in retinal vascular and choroidal endothelium, Müller glia, the retinal pigment epithelium (RPE), and the Schlemm's canal endothelium and trabecular meshwork cells. Variants at the CAV1/2 gene locus are associated with risk of primary open angle glaucoma and the high risk HTRA1 variant for age-related macular degeneration is thought to exert its effect through regulation of Cav1 expression. Caveolins also play important roles in modulating retinal neuroinflammation and blood retinal barrier permeability. In this article, we describe the current state of caveolin/caveolae research in the context of ocular function and pathophysiology. Finally, we discuss new evidence showing that retinal Cav1 exists and functions outside caveolae.
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Affiliation(s)
- Eric N Enyong
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Ophthalmology, Dean A. McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Jami M Gurley
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Ophthalmology, Dean A. McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Michael L De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, USA
| | - W Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, USA
| | - Michael H Elliott
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Ophthalmology, Dean A. McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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7
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Lewczuk K, Jabłońska J, Konopińska J, Mariak Z, Rękas M. Schlemm's canal: the outflow 'vessel'. Acta Ophthalmol 2022; 100:e881-e890. [PMID: 34519170 PMCID: PMC9293138 DOI: 10.1111/aos.15027] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 06/21/2021] [Accepted: 08/31/2021] [Indexed: 12/26/2022]
Abstract
In a healthy eye, the aqueous humour (AH) flows via the ciliary body and trabecular meshwork into the collector channels, which carry it to the episcleral veins. In glaucoma, a heterogeneous group of eye disorders affecting approximately 60 million individuals worldwide, the juxtacanalicular meshwork offers greater resistance to the outflow of the AH, leading to an increase in outflow resistance that gradually results in elevated intraocular pressure (IOP). The present review comprehensively covers the morphology of Schlemm’s canal (SC) and AH pathways. The path of the AH from the anterior chamber through the trabeculum into suprascleral and conjunctival veins via collector channels is described, and the role of SC in the development of glaucoma and outflow resistance is discussed. Finally, channelography is presented as a precise method of assessing the conventional drainage pathway and facilitating localization of an uncollapsed collector and aqueous veins. Attention is also given to the relationship between aqueous and episcleral veins and heartbeat. Possible directions of future research are proposed.
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Affiliation(s)
- Katarzyna Lewczuk
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
| | - Joanna Jabłońska
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
| | - Joanna Konopińska
- Department of Ophthalmology Medical University in Bialystok Białystok Poland
| | - Zofia Mariak
- Department of Ophthalmology Medical University in Bialystok Białystok Poland
| | - Marek Rękas
- Department of Ophthalmology Military Institute of Medicine Warsaw Poland
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8
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Li R, Wang TY, Xu X, Emery OM, Yi M, Wu SP, DeMayo FJ. Spatial transcriptomic profiles of mouse uterine microenvironments at pregnancy day 7.5†. Biol Reprod 2022; 107:529-545. [PMID: 35357464 PMCID: PMC9382390 DOI: 10.1093/biolre/ioac061] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 02/03/2022] [Accepted: 03/30/2022] [Indexed: 01/17/2023] Open
Abstract
Uterine dysfunctions lead to fertility disorders and pregnancy complications. Normal uterine functions at pregnancy depend on crosstalk among multiple cell types in uterine microenvironments. Here, we performed the spatial transcriptomics and single-cell RNA-seq assays to determine local gene expression profiles at the embryo implantation site of the mouse uterus on pregnancy day 7.5 (D7.5). The spatial transcriptomic annotation identified 11 domains of distinct gene signatures, including a mesometrial myometrium, an anti-mesometrial myometrium, a mesometrial decidua enriched with natural killer cells, a vascular sinus zone for maternal vessel remodeling, a fetal-maternal interface, a primary decidual zone, a transition decidual zone, a secondary decidual zone, undifferentiated stroma, uterine glands, and the embryo. The scRNA-Seq identified 12 types of cells in the D7.5 uterus including three types of stromal fibroblasts with differentiated and undifferentiated markers, one cluster of epithelium including luminal and glandular epithelium, mesothelium, endothelia, pericytes, myelomonocytic cell, natural killer cells, and lymphocyte B. These single-cell RNA signatures were then utilized to deconvolute the cell-type compositions of each individual uterine microenvironment. Functional annotation assays on spatial transcriptomic data revealed uterine microenvironments with distinguished metabolic preferences, immune responses, and various cellular behaviors that are regulated by region-specific endocrine and paracrine signals. Global interactome among regions is also projected based on the spatial transcriptomic data. This study provides high-resolution transcriptome profiles with locality information at the embryo implantation site to facilitate further investigations on molecular mechanisms for normal pregnancy progression.
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Affiliation(s)
- Rong Li
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Tian-yuan Wang
- Integrative Bioinformatics Supportive Group, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Xin Xu
- Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Olivia M Emery
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - MyeongJin Yi
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - San-Pin Wu
- Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Francesco J DeMayo
- Correspondence: Reproductive and Developmental Biology Laboratory, National Institute of Environmental Health Sciences, 111 T. W. Alexander Dr., Research Triangle Park, NC 27709, USA. Tel: +9842873987; E-mail:
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9
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De Ieso ML, Kuhn M, Bernatchez P, Elliott MH, Stamer WD. A Role of Caveolae in Trabecular Meshwork Mechanosensing and Contractile Tone. Front Cell Dev Biol 2022; 10:855097. [PMID: 35372369 PMCID: PMC8969750 DOI: 10.3389/fcell.2022.855097] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/03/2022] [Indexed: 11/13/2022] Open
Abstract
Polymorphisms in the CAV1/2 gene loci impart increased risk for primary open-angle glaucoma (POAG). CAV1 encodes caveolin-1 (Cav1), which is required for biosynthesis of plasma membrane invaginations called caveolae. Cav1 knockout mice exhibit elevated intraocular pressure (IOP) and decreased outflow facility, but the mechanistic role of Cav1 in IOP homeostasis is unknown. We hypothesized that caveolae sequester/inhibit RhoA, to regulate trabecular meshwork (TM) mechanosensing and contractile tone. Using phosphorylated myosin light chain (pMLC) as a surrogate indicator for Rho/ROCK activity and contractile tone, we found that pMLC was elevated in Cav1-deficient TM cells compared to control (131 ± 10%, n = 10, p = 0.016). Elevation of pMLC levels following Cav1 knockdown occurred in cells on a soft surface (137 ± 7%, n = 24, p < 0.0001), but not on a hard surface (122 ± 17%, n = 12, p = 0.22). In Cav1-deficient TM cells where pMLC was elevated, Rho activity was also increased (123 ± 7%, n = 6, p = 0.017), suggesting activation of the Rho/ROCK pathway. Cyclic stretch reduced pMLC/MLC levels in TM cells (69 ± 7% n = 9, p = 0.002) and in Cav1-deficient TM cells, although not significantly (77 ± 11% n = 10, p = 0.059). Treatment with the Cav1 scaffolding domain mimetic, cavtratin (1 μM) caused a reduction in pMLC (70 ± 5% n = 7, p = 0.001), as did treatment with the scaffolding domain mutant cavnoxin (1 μM) (82 ± 7% n = 7, p = 0.04). Data suggest that caveolae differentially regulate RhoA signaling, and that caveolae participate in TM mechanotransduction. Cav1 regulation of these key TM functions provide evidence for underlying mechanisms linking polymorphisms in the Cav1/2 gene loci with increased POAG risk.
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Affiliation(s)
- Michael L. De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States
| | - Megan Kuhn
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States
| | - Pascal Bernatchez
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Heart + Lung Innovation Centre, St. Paul’s Hospital, Vancouver, BC, Canada
| | - Michael H. Elliott
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - W. Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, United States
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10
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Sun H, Niu Q, Yang J, Zhao Y, Tian Z, Fan J, Zhang Z, Wang Y, Geng S, Zhang Y, Guan G, Williams DT, Luo J, Yin H, Liu Z. Transcriptome Profiling Reveals Features of Immune Response and Metabolism of Acutely Infected, Dead and Asymptomatic Infection of African Swine Fever Virus in Pigs. Front Immunol 2022; 12:808545. [PMID: 34975923 PMCID: PMC8714921 DOI: 10.3389/fimmu.2021.808545] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 11/29/2021] [Indexed: 12/16/2022] Open
Abstract
African swine fever virus (ASFV) infection can result in lethal disease in pigs. ASFV encodes 150-167 proteins, of which only approximately 50 encoded viral structure proteins are functionally known. ASFV also encodes some nonstructural proteins that are involved in the regulation of viral transcription, viral replication and evasion from host defense. However, the understanding of the molecular correlates of the severity of these infections is still limited. The purpose of this study was to compare host and viral gene expression differences and perform functional analysis in acutely infected, dead and cohabiting asymptomatic pigs infected with ASFV by using RNA-Seq technique; healthy pigs were used as controls. A total of 3,760 and 2,874 upregulated genes and 4,176 and 2,899 downregulated genes were found in healthy pigs vs. acutely infected, dead pigs or asymptomatic pigs, respectively. Additionally, 941 upregulated genes and 956 downregulated genes were identified in asymptomatic vs. acutely infected, dead pigs. Different alternative splicing (AS) events were also analyzed, as were gene chromosome locations, and protein-protein interaction (PPI) network prediction analysis was performed for significantly differentially expressed genes (DEGs). In addition, 30 DEGs were validated by RT-qPCR, and the results were consistent with the RNA-Seq results. We further analyzed the interaction between ASFV and its host at the molecular level and predicted the mechanisms responsible for asymptomatic pigs based on the selected DEGs. Interestingly, we found that some viral genes in cohabiting asymptomatic pigs might integrate into host genes (DP96R, I73R and L83L) or remain in the tissues of cohabiting asymptomatic pigs. In conclusion, the data obtained in the present study provide new evidence for further elucidating ASFV-host interactions and the ASFV infection mechanism and will facilitate the implementation of integrated strategies for controlling ASF spread.
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Affiliation(s)
- Hualin Sun
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Qingli Niu
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jifei Yang
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Yaru Zhao
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zhancheng Tian
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jie Fan
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Zhonghui Zhang
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Yiwang Wang
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Shuxian Geng
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Yulong Zhang
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Guiquan Guan
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - David T Williams
- Commonwealth Scientific and Industrial Research Organization (CSIRO) Australian Centre for Disease Preparedness, Geelong, VIC, Australia
| | - Jianxun Luo
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Hong Yin
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China
| | - Zhijie Liu
- African Swine Fever Regional Laboratory, China (Lanzhou) and State Key Laboratory of Veterinary Etiological Biology and Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
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11
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Andersson N, Haltia UM, Färkkilä A, Wong SC, Eloranta K, Wilson DB, Unkila-Kallio L, Pihlajoki M, Kyrönlahti A, Heikinheimo M. Analysis of Non-Relapsed and Relapsed Adult Type Granulosa Cell Tumors Suggests Stable Transcriptomes during Tumor Progression. Curr Issues Mol Biol 2022; 44:686-698. [PMID: 35723333 PMCID: PMC8928977 DOI: 10.3390/cimb44020048] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/17/2022] [Accepted: 01/24/2022] [Indexed: 11/16/2022] Open
Abstract
Adult-type granulosa cell tumor (AGCT) is a rare ovarian malignancy characterized by slow growth and hormonal activity. The prognosis of AGCT is generally favorable, but one-third of patients with low-stage disease experience a late relapse, and over half of them die of AGCT. To identify markers that would distinguish patients at risk for relapse, we performed Lexogen QuantSeq 3′ mRNA sequencing on formalin-fixed paraffin-embedded, archival AGCT tissue samples tested positive for the pathognomonic Forkhead Box L2 (FOXL2) mutation. We compared the transcriptomic profiles of 14 non-relapsed archival primary AGCTs (follow-up time 17–26 years after diagnosis) with 13 relapsed primary AGCTs (follow-up time 1.7–18 years) and eight relapsed tumors (follow-up time 2.8–18.9 years). Non-relapsed and relapsed primary AGCTs had similar transcriptomic profiles. In relapsed tumors three genes were differentially expressed: plasmalemma vesicle associated protein (PLVAP) was upregulated (p = 0.01), whereas argininosuccinate synthase 1 (ASS1) (p = 0.01) and perilipin 4 (PLIN4) (p = 0.02) were downregulated. PLVAP upregulation was validated using tissue microarray RNA in situ hybridization. In our patient cohort with extremely long follow-up, we observed similar gene expression patterns in both primary AGCT groups, suggesting that relapse is not driven by transcriptomic changes. These results reinforce earlier findings that molecular markers do not predict AGCT behavior or risk of relapse.
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Affiliation(s)
- Noora Andersson
- HUSLAB, Helsinki University Hospital, Haartmaninkatu 4, 00290 Helsinki, Finland;
- Pediatric Research Center, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8, 00290 Helsinki, Finland; (K.E.); (A.K.); (M.H.)
| | - Ulla-Maija Haltia
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 2, 00290 Helsinki, Finland; (U.-M.H.); (A.F.); (L.U.-K.)
| | - Anniina Färkkilä
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 2, 00290 Helsinki, Finland; (U.-M.H.); (A.F.); (L.U.-K.)
- Research Program for Systems Oncology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 8, 00290 Helsinki, Finland
| | | | - Katja Eloranta
- Pediatric Research Center, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8, 00290 Helsinki, Finland; (K.E.); (A.K.); (M.H.)
| | - David B. Wilson
- Department of Pediatrics, Washington University in St. Louis, 660 S Euclid Ave, St. Louis, MO 63110, USA;
- Department of Developmental Biology, Washington University School of Medicine, 660 S. Euclid Avenue Campus Box 8103, St. Louis, MO 63110, USA
| | - Leila Unkila-Kallio
- Department of Obstetrics and Gynecology, University of Helsinki and Helsinki University Hospital, Haartmaninkatu 2, 00290 Helsinki, Finland; (U.-M.H.); (A.F.); (L.U.-K.)
| | - Marjut Pihlajoki
- Pediatric Research Center, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8, 00290 Helsinki, Finland; (K.E.); (A.K.); (M.H.)
- Correspondence:
| | - Antti Kyrönlahti
- Pediatric Research Center, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8, 00290 Helsinki, Finland; (K.E.); (A.K.); (M.H.)
| | - Markku Heikinheimo
- Pediatric Research Center, Children’s Hospital, University of Helsinki and Helsinki University Hospital, Tukholmankatu 8, 00290 Helsinki, Finland; (K.E.); (A.K.); (M.H.)
- Department of Pediatrics, Washington University in St. Louis, 660 S Euclid Ave, St. Louis, MO 63110, USA;
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12
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Brinks J, van Dijk EHC, Klaassen I, Schlingemann RO, Kielbasa SM, Emri E, Quax PHA, Bergen AA, Meijer OC, Boon CJF. Exploring the choroidal vascular labyrinth and its molecular and structural roles in health and disease. Prog Retin Eye Res 2021; 87:100994. [PMID: 34280556 DOI: 10.1016/j.preteyeres.2021.100994] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 07/04/2021] [Accepted: 07/07/2021] [Indexed: 12/14/2022]
Abstract
The choroid is a key player in maintaining ocular homeostasis and plays a role in a variety of chorioretinal diseases, many of which are poorly understood. Recent advances in the field of single-cell RNA sequencing have yielded valuable insights into the properties of choroidal endothelial cells (CECs). Here, we review the role of the choroid in various physiological and pathophysiological mechanisms, focusing on the role of CECs. We also discuss new insights regarding the phenotypic properties of CECs, CEC subpopulations, and the value of measuring transcriptomics in primary CEC cultures derived from post-mortem eyes. In addition, we discuss key phenotypic, structural, and functional differences that distinguish CECs from other endothelial cells such as retinal vascular endothelial cells. Understanding the specific clinical and molecular properties of the choroid will shed new light on the pathogenesis of the broad clinical range of chorioretinal diseases such as age-related macular degeneration, central serous chorioretinopathy and other diseases within the pachychoroid spectrum, uveitis, and diabetic choroidopathy. Although our knowledge is still relatively limited with respect to the clinical features and molecular pathways that underlie these chorioretinal diseases, we summarise new approaches and discuss future directions for gaining new insights into these sight-threatening diseases and highlight new therapeutic strategies such as pluripotent stem cell‒based technologies and gene therapy.
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Affiliation(s)
- J Brinks
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - E H C van Dijk
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - I Klaassen
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands
| | - R O Schlingemann
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands; Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands; Department of Ophthalmology, University of Lausanne, Jules Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - S M Kielbasa
- Department of Medical Statistics and Bioinformatics, Leiden University Medical Center, Leiden, the Netherlands
| | - E Emri
- Department of Clinical Genetics, Section of Ophthalmogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - P H A Quax
- Department of Vascular Surgery, Leiden University Medical Center, Leiden, the Netherlands; Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - A A Bergen
- Department of Clinical Genetics, Section of Ophthalmogenetics, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - O C Meijer
- Department of Medicine, Division of Endocrinology and Metabolism, Leiden University Medical Center, Leiden, the Netherlands
| | - C J F Boon
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands; Department of Ophthalmology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, the Netherlands.
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13
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Saxena V, Gao H, Arregui S, Zollman A, Kamocka MM, Xuei X, McGuire P, Hutchens M, Hato T, Hains DS, Schwaderer AL. Kidney intercalated cells are phagocytic and acidify internalized uropathogenic Escherichia coli. Nat Commun 2021; 12:2405. [PMID: 33893305 PMCID: PMC8065053 DOI: 10.1038/s41467-021-22672-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 03/18/2021] [Indexed: 02/02/2023] Open
Abstract
Kidney intercalated cells are involved in acid-base homeostasis via vacuolar ATPase expression. Here we report six human intercalated cell subtypes, including hybrid principal-intercalated cells identified from single cell transcriptomics. Phagosome maturation is a biological process that increases in biological pathway analysis rank following exposure to uropathogenic Escherichia coli in two of the intercalated cell subtypes. Real time confocal microscopy visualization of murine renal tubules perfused with green fluorescent protein expressing Escherichia coli or pHrodo Green E. coli BioParticles demonstrates that intercalated cells actively phagocytose bacteria then acidify phagolysosomes. Additionally, intercalated cells have increased vacuolar ATPase expression following in vivo experimental UTI. Taken together, intercalated cells exhibit a transcriptional response conducive to the kidney's defense, engulf bacteria and acidify the internalized bacteria. Intercalated cells represent an epithelial cell with characteristics of professional phagocytes like macrophages.
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Affiliation(s)
- Vijay Saxena
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA.
| | - Hongyu Gao
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Samuel Arregui
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA
| | - Amy Zollman
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - Malgorzata Maria Kamocka
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - Xiaoling Xuei
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Patrick McGuire
- Indiana University School of Medicine, Department of Medical & Molecular Genetics, Indianapolis, IN, USA
| | - Michael Hutchens
- Oregon Health and Science University, Department of Anesthesiology & Perioperative Medicine, Portland, OR, USA
| | - Takashi Hato
- Indiana University School of Medicine, Department of Medicine, Division of Nephrology, Indianapolis, IN, USA
| | - David S Hains
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA
| | - Andrew L Schwaderer
- Indiana University School of Medicine, Department of Pediatrics, Division of Nephrology, Indianapolis, IN, USA.
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14
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De Ieso ML, Gurley JM, McClellan ME, Gu X, Navarro I, Li G, Gomez-Caraballo M, Enyong E, Stamer WD, Elliott MH. Physiologic Consequences of Caveolin-1 Ablation in Conventional Outflow Endothelia. Invest Ophthalmol Vis Sci 2021; 61:32. [PMID: 32940661 PMCID: PMC7500130 DOI: 10.1167/iovs.61.11.32] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Purpose Polymorphisms at the caveolin-1/2 locus are associated with glaucoma and IOP risk and deletion of caveolin-1 (Cav1) in mice elevates IOP and reduces outflow facility. However, the specific location/cell type responsible for Cav1-dependent regulation of IOP is unclear. We hypothesized that endothelial Cav1 in the conventional outflow (CO) pathway regulate IOP via endothelial nitric oxide synthase (eNOS) signaling. Methods We created a mouse with targeted deletion of Cav1 in endothelial cells (Cav1ΔEC) and evaluated IOP, outflow facility, outflow pathway distal vascular morphology, eNOS phosphorylation, and tyrosine nitration of iridocorneal angle tissues by Western blotting. Results Endothelial deletion of Cav1 resulted in significantly elevated IOP versus wild-type mice but not a concomitant decrease in outflow facility. Endothelial Cav1 deficiency did not alter the trabecular meshwork or Schlemm's canal morphology, suggesting that the effects observed were not due to developmental deformities. Endothelial Cav1 deletion resulted in eNOS hyperactivity, modestly increased protein nitration, and significant enlargement of the drainage vessels distal to Schlemm's canal. L-Nitro-arginine methyl ester treatment reduced outflow in Cav1ΔEC but not wild-type mice and had no effect on the size of drainage vessels. Endothelin-1 treatment decrease the outflow and drainage vessel size in both wild-type and Cav1ΔEC mice. Conclusions Our results suggest that hyperactive eNOS signaling in the CO pathway of both Cav1ΔEC and global Cav1 knockout mice results in chronic dilation of distal CO vessels and protein nitration, but that Cav1 expression in the trabecular meshwork is sufficient to rescue CO defects reported in global Cav1 knockout mice.
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Affiliation(s)
- Michael L De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Jami M Gurley
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Mark E McClellan
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Xiaowu Gu
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Iris Navarro
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Guorong Li
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Maria Gomez-Caraballo
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Eric Enyong
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - W Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Michael H Elliott
- Department of Ophthalmology, Dean McGee Eye Institute University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States.,Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
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15
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Dillinger AE, Kuespert S, Froemel F, Tamm ER, Fuchshofer R. CCN2/CTGF promotor activity in the developing and adult mouse eye. Cell Tissue Res 2021; 384:625-641. [PMID: 33512643 PMCID: PMC8211604 DOI: 10.1007/s00441-020-03332-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 10/29/2020] [Indexed: 12/23/2022]
Abstract
CCN2/CTGF is a matricellular protein that is known to enhance transforming growth factor-β signaling and to induce a myofibroblast-like phenotype in a variety of cell types. Here, we investigated Ccn2/Ctgf promotor activity during development and in the adult mouse eye, using CTGFLacZ/+ mice in which the β-galactosidase reporter gene LacZ had been inserted into the open reading frame of Ccn2/Ctgf. Promotor activity was assessed by staining for β-galactosidase activity and by immunolabeling using antibodies against β-galactosidase. Co-immunostaining using antibodies against glutamine synthetase, glial fibrillary acidic protein, choline acetyltransferase, and CD31 was applied to identify specific cell types. Ccn2/Ctgf promotor activity was intense in neural crest-derived cells differentiating to corneal stroma and endothelium, and to the stroma of choroid, iris, ciliary body, and the trabecular meshwork during development. In the adult eye, a persistent and very strong promotor activity was present in the trabecular meshwork outflow pathways. In addition, endothelial cells of Schlemm’s canal, and of retinal and choroidal vessels, retinal astrocytes, Müller glia, and starburst amacrine cells were stained. Very strong promoter activity was seen in the astrocytes of the glial lamina at the optic nerve head. We conclude that CCN2/CTGF signaling is involved in the processes that govern neural crest morphogenesis during ocular development. In the adult eye, CCN2/CTGF likely plays an important role for the trabecular meshwork outflow pathways and the glial lamina of the optic nerve head.
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Affiliation(s)
- Andrea E Dillinger
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Sabrina Kuespert
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Franziska Froemel
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Ernst R Tamm
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, 93053, Regensburg, Germany.
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16
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Reina-Torres E, De Ieso ML, Pasquale LR, Madekurozwa M, van Batenburg-Sherwood J, Overby DR, Stamer WD. The vital role for nitric oxide in intraocular pressure homeostasis. Prog Retin Eye Res 2020; 83:100922. [PMID: 33253900 DOI: 10.1016/j.preteyeres.2020.100922] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023]
Abstract
Catalyzed by endothelial nitric oxide (NO) synthase (eNOS) activity, NO is a gaseous signaling molecule maintaining endothelial and cardiovascular homeostasis. Principally, NO regulates the contractility of vascular smooth muscle cells and permeability of endothelial cells in response to either biochemical or biomechanical cues. In the conventional outflow pathway of the eye, the smooth muscle-like trabecular meshwork (TM) cells and Schlemm's canal (SC) endothelium control aqueous humor outflow resistance, and therefore intraocular pressure (IOP). The mechanisms by which outflow resistance is regulated are complicated, but NO appears to be a key player as enhancement or inhibition of NO signaling dramatically affects outflow function; and polymorphisms in NOS3, the gene that encodes eNOS modifies the relation between various environmental exposures and glaucoma. Based upon a comprehensive review of past foundational studies, we present a model whereby NO controls a feedback signaling loop in the conventional outflow pathway that is sensitive to changes in IOP and its oscillations. Thus, upon IOP elevation, the outflow pathway tissues distend, and the SC lumen narrows resulting in increased SC endothelial shear stress and stretch. In response, SC cells upregulate the production of NO, relaxing neighboring TM cells and increasing permeability of SC's inner wall. These IOP-dependent changes in the outflow pathway tissues reduce the resistance to aqueous humor drainage and lower IOP, which, in turn, diminishes the biomechanical signaling on SC. Similar to cardiovascular pathogenesis, dysregulation of the eNOS/NO system leads to dysfunctional outflow regulation and ocular hypertension, eventually resulting in primary open-angle glaucoma.
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Affiliation(s)
| | | | - Louis R Pasquale
- Eye and Vision Research Institute of New York Eye and Ear Infirmary at Mount Sinai, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | | | - Darryl R Overby
- Department of Bioengineering, Imperial College London, London, UK.
| | - W Daniel Stamer
- Department of Ophthalmology, Duke University, Durham, NC, USA.
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17
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van Zyl T, Yan W, McAdams A, Peng YR, Shekhar K, Regev A, Juric D, Sanes JR. Cell atlas of aqueous humor outflow pathways in eyes of humans and four model species provides insight into glaucoma pathogenesis. Proc Natl Acad Sci U S A 2020; 117:10339-10349. [PMID: 32341164 PMCID: PMC7229661 DOI: 10.1073/pnas.2001250117] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Increased intraocular pressure (IOP) represents a major risk factor for glaucoma, a prevalent eye disease characterized by death of retinal ganglion cells; lowering IOP is the only proven treatment strategy to delay disease progression. The main determinant of IOP is the equilibrium between production and drainage of aqueous humor, with compromised drainage generally viewed as the primary contributor to dangerous IOP elevations. Drainage occurs through two pathways in the anterior segment of the eye called conventional and uveoscleral. To gain insights into the cell types that comprise these pathways, we used high-throughput single-cell RNA sequencing (scRNAseq). From ∼24,000 single-cell transcriptomes, we identified 19 cell types with molecular markers for each and used histological methods to localize each type. We then performed similar analyses on four organisms used for experimental studies of IOP dynamics and glaucoma: cynomolgus macaque (Macaca fascicularis), rhesus macaque (Macaca mulatta), pig (Sus scrofa), and mouse (Mus musculus). Many human cell types had counterparts in these models, but differences in cell types and gene expression were evident. Finally, we identified the cell types that express genes implicated in glaucoma in all five species. Together, our results provide foundations for investigating the pathogenesis of glaucoma and for using model systems to assess mechanisms and potential interventions.
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Affiliation(s)
- Tavé van Zyl
- Department of Ophthalmology, Harvard Medical School and Massachusetts Eye and Ear, Boston, MA 02114;
- Center for Brain Science, Harvard University, Cambridge, MA 02138
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Wenjun Yan
- Center for Brain Science, Harvard University, Cambridge, MA 02138
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Alexi McAdams
- Department of Ophthalmology, Harvard Medical School and Massachusetts Eye and Ear, Boston, MA 02114
- Center for Brain Science, Harvard University, Cambridge, MA 02138
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Yi-Rong Peng
- Center for Brain Science, Harvard University, Cambridge, MA 02138
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
| | - Karthik Shekhar
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142
- Koch Institute of Integrative Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Aviv Regev
- Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02142
- Koch Institute of Integrative Cancer Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
- Klarman Cell Observatory, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, MA 02142
| | - Dejan Juric
- Department of Medicine, Harvard Medical School and Massachusetts General Hospital Cancer Center, Boston, MA 02114
| | - Joshua R Sanes
- Center for Brain Science, Harvard University, Cambridge, MA 02138;
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
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18
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Lu SY, Rong SS, Wu Z, Huang C, Matsushita K, Ng TK, Leung CKS, Kawashima R, Usui S, Tam POS, Tsujikawa M, Young AL, Zhang M, Wiggs JL, Nishida K, Tham CC, Pang CP, Chen LJ. Association of the CAV1-CAV2 locus with normal-tension glaucoma in Chinese and Japanese. Clin Exp Ophthalmol 2020; 48:658-665. [PMID: 32162426 DOI: 10.1111/ceo.13744] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 01/10/2020] [Accepted: 02/17/2020] [Indexed: 12/17/2022]
Abstract
BACKGROUND The CAV1-CAV2 locus has been associated with primary open-angle glaucoma (POAG) and intraocular pressure. However, its association with normal-tension glaucoma (NTG) was inconclusive. Therefore, we evaluated this association in Chinese and Japanese. METHODS Two single-nucleotide polymorphisms (SNPs, rs4236601 and rs1052990) from previous genome-wide association studies of POAG were genotyped in a total of 2220 study subjects: a Hong Kong Chinese cohort of 537 NTG patients and 490 controls, a Shantou Chinese cohort of 102 NTG and 731 controls and an Osaka Japanese cohort of 153 NTG and 207 controls. Subgroup analysis by gender was conducted. Outcomes from different cohorts were combined using meta-analysis. RESULTS SNP rs4236601 was significantly associated with NTG in the two Chinese cohorts (Pmeta = .0019, OR = 4.55, I2 = 0). In contrast, rs4236601 was monomorphic in the Osaka cohort. The association of rs1052990 was insignificant in a meta-analysis combining Chinese and Japanese cohorts (Pmeta = .81, OR = 1.05; I2 = 64%), and the OR tended towards opposite directions between Chinese (OR = 1.26) and Japanese (OR = 0.69). Gender-specific effects of the SNPs were not statistically significant in the logistic regression or Breslow-day tests of ORs (P > .05), although rs4236601 was significant in males (P = .0068; OR = 10.30) but not in females (P = .14; OR = 2.65) in the meta-analysis of Chinese subjects. CONCLUSIONS In this study, we confirmed the association of rs4236601 at the CAV1-CAV2 locus with NTG in Chinese. SNP rs4236601 is monomorphic, and rs1052990 tends towards a different direction in the Japanese cohort. Further studies are warranted to verify the ethnic difference and gender-specific effects of this locus.
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Affiliation(s)
- Shi Yao Lu
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China
| | - Shi Song Rong
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Zhenggen Wu
- Joint Shantou International Eye Center of Shantou University, and the Chinese University of Hong Kong, Shantou, China
| | - Chukai Huang
- Joint Shantou International Eye Center of Shantou University, and the Chinese University of Hong Kong, Shantou, China
| | - Kenji Matsushita
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tsz Kin Ng
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Joint Shantou International Eye Center of Shantou University, and the Chinese University of Hong Kong, Shantou, China
| | - Christopher K S Leung
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Hong Kong Eye Hospital, the Chinese University of Hong Kong, Hong Kong, China
| | - Rumi Kawashima
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shinichi Usui
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Pancy O S Tam
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China
| | - Motokazu Tsujikawa
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Alvin L Young
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong, China
| | - Mingzhi Zhang
- Joint Shantou International Eye Center of Shantou University, and the Chinese University of Hong Kong, Shantou, China
| | - Janey L Wiggs
- Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, USA
| | - Kohji Nishida
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Clement C Tham
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Hong Kong Eye Hospital, the Chinese University of Hong Kong, Hong Kong, China
| | - Chi Pui Pang
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Joint Shantou International Eye Center of Shantou University, and the Chinese University of Hong Kong, Shantou, China
| | - Li Jia Chen
- Department of Ophthalmology and Visual Sciences, the Chinese University of Hong Kong, Hong Kong, China.,Department of Ophthalmology and Visual Sciences, Prince of Wales Hospital, Hong Kong, China
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19
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Pawlak JB, Caron KM. Lymphatic Programing and Specialization in Hybrid Vessels. Front Physiol 2020; 11:114. [PMID: 32153423 PMCID: PMC7044189 DOI: 10.3389/fphys.2020.00114] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/31/2020] [Indexed: 12/14/2022] Open
Abstract
Building on a large body of existing blood vascular research, advances in lymphatic research have helped kindle broader investigations into vascular diversity and endothelial plasticity. While the endothelium of blood and lymphatic vessels can be distinguished by a variety of molecular markers, the endothelia of uniquely diverse vascular beds can possess distinctly heterogeneous or hybrid expression patterns. These expression patterns can then provide further insight on the development of these vessels and how they perform their specialized function. In this review we examine five highly specialized hybrid vessel beds that adopt partial lymphatic programing for their specialized vascular functions: the high endothelial venules of secondary lymphoid organs, the liver sinusoid, the Schlemm’s canal of the eye, the renal ascending vasa recta, and the remodeled placental spiral artery. We summarize the morphology and endothelial expression pattern of these vessels, compare them to each other, and interrogate their specialized functions within the broader blood and lymphatic vascular systems.
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Affiliation(s)
- John B Pawlak
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Kathleen M Caron
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
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20
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Song M, Li L, Lei Y, Sun X. NOS3 Deletion in Cav1 Deficient Mice Decreases Drug Sensitivity to a Nitric Oxide Donor and Two Nitric Oxide Synthase Inhibitors. Invest Ophthalmol Vis Sci 2020; 60:4002-4007. [PMID: 31560766 DOI: 10.1167/iovs.19-27582] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose This study aims to investigate the pharmacologic consequence of genetic deletion of nitric oxide synthase 3 (NOS3) in caveolin 1 (Cav1)-/- mice (double knockout [DKO]) in response to a nitric oxide (NO) donor and two NOS inhibitors. Methods NO donor sodium nitroprusside (SNP; 10-40 mg/mL), NOS inhibitor L-NG-nitroarginine methyl ester (L-NAME; 10-200 μM), and cavtratin (10-75 μM ) was administered topically to the eye while the contralateral eyes were vehicle controls. Intraocular pressure (IOP) was measured in both eyes by tonometry. Cyclic guanosine monophosphate (cGMP) level in outflow tissue was measured by ELISA assay. Protein expression were analyzed by western blot. Results Inducible NOS (iNOS) expression significantly increased in the DKO mice compared with the wild type (WT), Cav1 knockout (Cav1 KO), and NOS3 KO mice. In contrast to WT, Cav1 KO and NOS3 KO mice, SNP concentration of up to 30 mg/mL did not significantly affect IOP in DKO mice. However, higher concentration (40 mg/mL) SNP significantly reduced IOP by 14% (n = 8, P < 0.01). Similarly, only 200 μM L-NAME produced a significant increase in IOP (n = 10, P < 0.05). Cavtratin did not significantly change IOP in DKO and NOS3 KO mice. cGMP activity in DKO mice was significantly lower than Cav1 KO mice (n = 4, P < 0.05). Conclusions In conclusion, our results demonstrated that genetic deletion of NOS3 in Cav1 deficient mice resulted in reduced sensitivity to the NO donor SNP and the two NOS inhibitors possibly due to compromised NOS and cGMP activity.
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Affiliation(s)
- Maomao Song
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Liping Li
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yuan Lei
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Ministry of Health, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Ministry of Health, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, China
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21
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Single-cell transcriptomics of the human retinal pigment epithelium and choroid in health and macular degeneration. Proc Natl Acad Sci U S A 2019; 116:24100-24107. [PMID: 31712411 PMCID: PMC6883845 DOI: 10.1073/pnas.1914143116] [Citation(s) in RCA: 212] [Impact Index Per Article: 42.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The retinal pigment epithelium and the choroid are complex tissues whose dysfunction can lead to irreversible visual loss. In this study, single-cell RNA sequencing of both of these tissues was performed to characterize gene expression patterns specific to the retinal pigment epithelium and all major choroidal cell populations. Unique gene expression signatures of arterial, venous, and choriocapillaris vascular beds within the choroid were identified. RGCC, a gene that responds to complement and has been shown to induce endothelial apoptosis, was specifically expressed in choriocapillaris endothelial cells. This study provides potential insight into the molecular mechanisms of choroidal vascular disease and its contribution to age-related macular degeneration. The human retinal pigment epithelium (RPE) and choroid are complex tissues that provide crucial support to the retina. Disease affecting either of these supportive tissues can lead to irreversible blindness in the setting of age-related macular degeneration. In this study, single-cell RNA sequencing was performed on macular and peripheral regions of RPE-choroid from 7 human donor eyes in 2 independent experiments. In the first experiment, total RPE/choroid preparations were evaluated and expression profiles specific to RPE and major choroidal cell populations were identified. As choroidal endothelial cells represent a minority of the total RPE/choroidal cell population but are strongly implicated in age-related macular degeneration (AMD) pathogenesis, a second single-cell RNA-sequencing experiment was performed using endothelial cells enriched by magnetic separation. In this second study, we identified gene expression signatures along the choroidal vascular tree, classifying the transcriptome of human choriocapillaris, arterial, and venous endothelial cells. We found that the choriocapillaris highly and specifically expresses the regulator of cell cycle gene (RGCC), a gene that responds to complement activation and induces apoptosis in endothelial cells. In addition, RGCC was the most up-regulated choriocapillaris gene in a donor diagnosed with AMD. These results provide a characterization of the human RPE and choriocapillaris transcriptome, offering potential insight into the mechanisms of choriocapillaris response to complement injury and choroidal vascular disease in age-related macular degeneration.
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22
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Grebe R, Mughal I, Bryden W, McLeod S, Edwards M, Hageman GS, Lutty G. Ultrastructural analysis of submacular choriocapillaris and its transport systems in AMD and aged control eyes. Exp Eye Res 2019; 181:252-262. [PMID: 30807744 DOI: 10.1016/j.exer.2019.02.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 01/31/2019] [Accepted: 02/21/2019] [Indexed: 01/11/2023]
Abstract
The choriocapillaris is the source of nutrients and oxygen for photoreceptors, which consume more oxygen per gram of tissue than any other cell in the body. The purpose of this study was to evaluate and compare the ultrastructure of the choriocapillaris and its transport systems in patients with and without age-related macular degeneration (AMD). Ultrastructural changes were also evaluated in subjects that were homozygous for polymorphisms in high risk CFH alleles (Pure 1) only or homozygous only for high risk ARMS2/HTRA1 (Pure 10) alleles. Tissue samples were obtained from the macular region of forty male (n = 24) and female (n = 16) donor eyes and prepared for ultrastructural studies with transmission electron microscopy (TEM). The average age of the aged donors was 74 ± 7.2 (n = 30) and the young donors 31.7 ± 11.25 (n = 10). There was no significant difference in average ages between the adult groups. TEM images of the capillaries in the choriocapillaris (CC) were taken at 4,000X and 25,000X and used to measure the area of endothelial cell somas, the number of fenestrations, and area of caveolae within the endothelial cells per length of Bruchs membrane (BrMb). The Student t-test and Wilcoxon sum rank test were used to determine significant differences. There was no significant difference between young subjects and aged controls in any of the morphological criteria assessed. There was a significant decrease in the number of fenestrations/mm of BrMb in atrophic areas of GA eyes (p = 0.007) when compared with aged control eyes. A significant increase was found in the caveolae area as a percent of the endothelial cell soma of capillaries from GA subjects as compared with the controls (p = 0.03). Loss of capillary segments in choriocapillaris was also evident, especially in areas of geographic atrophy and CNV. In eyes from patients with sequence variations, the capillary endothelial cells often appeared degenerative and exhibited atypical fenestrations and pericytes covering the blood vessels. Subjects that were homozygous for polymorphisms in high risk CFH alleles only had more fenestrations/mm of BrMb than subjects that were homozygous only for high risk ARMS2/HTRA1 alleles (p = 0.04), while the latter had greater caveolae area/endothelial cell area than the former (p = 0.007). This study demonstrated an attenuation of CC and a significant decline in the two major transport systems in CC endothelial cells in AMD. This may contribute to drusen deposition, nutrient transport, and vision loss in AMD subjects.
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Affiliation(s)
- Rhonda Grebe
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA
| | - Irum Mughal
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA
| | - William Bryden
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA
| | - Scott McLeod
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA
| | - Malia Edwards
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA
| | - Gregory S Hageman
- John A. Moran Eye Center, Steele Center for Translational Medicine, Dept. of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, 84132, USA
| | - Gerard Lutty
- The Wilmer Ophthalmological Institute, Dept. of Ophthalmology, The Johns Hopkins Hospital, Baltimore, MD, 21287-9915, USA.
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23
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Bosma EK, van Noorden CJF, Schlingemann RO, Klaassen I. The role of plasmalemma vesicle-associated protein in pathological breakdown of blood-brain and blood-retinal barriers: potential novel therapeutic target for cerebral edema and diabetic macular edema. Fluids Barriers CNS 2018; 15:24. [PMID: 30231925 PMCID: PMC6146740 DOI: 10.1186/s12987-018-0109-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 08/10/2018] [Indexed: 12/14/2022] Open
Abstract
Breakdown of the blood–brain barrier (BBB) or inner blood–retinal barrier (BRB), induced by pathologically elevated levels of vascular endothelial growth factor (VEGF) or other mediators, can lead to vasogenic edema and significant clinical problems such as neuronal morbidity and mortality, or vision loss. Restoration of the barrier function with corticosteroids in the brain, or by blocking VEGF in the eye are currently the predominant treatment options for brain edema and diabetic macular edema, respectively. However, corticosteroids have side effects, and VEGF has important neuroprotective, vascular protective and wound healing functions, implying that long-term anti-VEGF therapy may also induce adverse effects. We postulate that targeting downstream effector proteins of VEGF and other mediators that are directly involved in the regulation of BBB and BRB integrity provide more attractive and safer treatment options for vasogenic cerebral edema and diabetic macular edema. The endothelial cell-specific protein plasmalemma vesicle-associated protein (PLVAP), a protein associated with trans-endothelial transport, emerges as candidate for this approach. PLVAP is expressed in a subset of endothelial cells throughout the body where it forms the diaphragms of caveolae, fenestrae and trans-endothelial channels. However, PLVAP expression in brain and eye barrier endothelia only occurs in pathological conditions associated with a compromised barrier function such as cancer, ischemic stroke and diabetic retinopathy. Here, we discuss the current understanding of PLVAP as a structural component of endothelial cells and regulator of vascular permeability in health and central nervous system disease. Besides providing a perspective on PLVAP identification, structure and function, and the regulatory processes involved, we also explore its potential as a novel therapeutic target for vasogenic cerebral edema and retinal macular edema.
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Affiliation(s)
- Esmeralda K Bosma
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Cornelis J F van Noorden
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.,Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Reinier O Schlingemann
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands.,Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - Ingeborg Klaassen
- Ocular Angiogenesis Group, Departments of Ophthalmology and Medical Biology, Amsterdam Cardiovascular Sciences, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands. .,Ocular Angiogenesis Group, Department of Medical Biology, Amsterdam UMC, University of Amsterdam, Meibergdreef 15, Room L3-154, 1105 AZ, Amsterdam, The Netherlands.
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24
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Aktas Z, Rao H, Slauson SR, Gabelt BT, Larsen IV, Sheridan RTC, Herrnberger L, Tamm ER, Kaufman PL, Brandt CR. Proteasome Inhibition Increases the Efficiency of Lentiviral Vector-Mediated Transduction of Trabecular Meshwork. Invest Ophthalmol Vis Sci 2018; 59:298-310. [PMID: 29340644 PMCID: PMC5961099 DOI: 10.1167/iovs.17-22074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Purpose To determine if proteasome inhibition using MG132 increased the efficiency of FIV vector–mediated transduction in human trabecular meshwork (TM)-1 cells and monkey organ-cultured anterior segments (MOCAS). Methods TM-1 cells were pretreated for 1 hour with 0.5% dimethyl sulfoxide (DMSO; vehicle control) or 5 to 50 μM MG132 and transduced with FIV.GFP (green fluorescent protein)– or FIV.mCherry-expressing vector at a multiplicity of transduction (MOT) of 20. At 24 hours, cells were fixed and stained with antibodies for GFP, and positive cells were counted, manually or by fluorescence-activated cell sorting (FACS). Cells transduced with FIV.GFP particles alone were used as controls. The effect of 20 μM MG132 treatment on high- and low-dose (2 × 107 and 0.8 × 107 transducing units [TU], respectively) FIV.GFP transduction with or without MG132 was also evaluated in MOCAS using fluorescence microscopy. Vector genome equivalents in cells and tissues were quantified by quantitative (q)PCR on DNA. Results In the MG132 treatment groups, there was a significant dose-dependent increase in the percentage of transduced cells at all concentrations tested. Vector genome equivalents were also increased in TM-1 cells treated with MG132. Increased FIV.GFP expression in the TM was also observed in MOCAS treated with 20 μM MG132 and the high dose of vector. Vector genome equivalents were also significantly increased in the MOCAS tissues. Increased transduction was not seen with the low dose of virus. Conclusions Proteasome inhibition increased the transduction efficiency of FIV particles in TM-1 cells and MOCAS and may be a useful adjunct for delivery of therapeutic genes to the TM by lentiviral vectors.
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Affiliation(s)
- Zeynep Aktas
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Ophthalmology, Gazi University Medical Faculty, Ankara, Turkey
| | - Hongyu Rao
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Sarah R Slauson
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - B'Ann T Gabelt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Inna V Larsen
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Rachael T C Sheridan
- UW Carbone Cancer Center Flow Cytometry Laboratory, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Leonie Herrnberger
- Institute of Human Anatomy, University of Regensburg, Regensburg, Germany
| | - Ernst R Tamm
- Institute of Human Anatomy, University of Regensburg, Regensburg, Germany
| | - Paul L Kaufman
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Curtis R Brandt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States
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25
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Broekaert IJ, Becker K, Gottschalk I, Körber F, Dötsch J, Thiele H, Altmüller J, Nürnberg P, Hünseler C, Cirak S. Mutations in plasmalemma vesicle-associated protein cause severe syndromic protein-losing enteropathy. J Med Genet 2018; 55:637-640. [PMID: 29661969 DOI: 10.1136/jmedgenet-2018-105262] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/19/2018] [Accepted: 03/22/2018] [Indexed: 11/03/2022]
Abstract
BACKGROUND Protein-losing enteropathy (PLE) is characterised by gastrointestinal protein leakage due to loss of mucosal integrity or lymphatic abnormalities. PLE can manifest as congenital diarrhoea and should be differentiated from other congenital diarrhoeal disorders. Primary PLEs are genetically heterogeneous and the underlying genetic defects are currently emerging. OBJECTIVES We report an infant with fatal PLE for whom we aimed to uncover the underlying pathogenic mutation. METHODS We performed whole exome sequencing (WES) for the index patient. Variants were classified based on the American College of Medical Genetics and Genomics guidelines. WES results and our detailed clinical description of the patient were compared with the literature. RESULTS We discovered a novel homozygous stop mutation (c.988C>T, p.Q330*) in the Plasmalemma Vesicle-Associated Protein (PLVAP) gene in a newborn with fatal PLE, facial dysmorphism, and renal, ocular and cardiac anomalies. The Q330* mutation is predicted to result in complete loss of PLVAP protein expression leading to deletion of the diaphragms of endothelial fenestrae, resulting in plasma protein extravasation and PLE. Recently, another single homozygous stop mutation in PLVAP causing lethal PLE in an infant was reported. CONCLUSIONS Our findings validate PLVAP mutations as a cause of syndromic PLE. Prenatal anomalies, severe PLE and syndromic features may guide the diagnosis of this rare disease.
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Affiliation(s)
| | - Kerstin Becker
- Department of Pediatrics, University Hospital Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Ingo Gottschalk
- Department of Gynecology, University Hospital Cologne, Cologne, Germany
| | - Friederike Körber
- Department of Radiology, University Hospital Cologne, Cologne, Germany
| | - Jörg Dötsch
- Department of Pediatrics, University Hospital Cologne, Cologne, Germany
| | - Holger Thiele
- Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | - Janine Altmüller
- Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | - Peter Nürnberg
- Cologne Center for Genomics, University of Cologne, Cologne, Germany
| | | | - Sebahattin Cirak
- Department of Pediatrics, University Hospital Cologne, Cologne, Germany
- Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
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26
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Erickson MA, Banks WA. Neuroimmune Axes of the Blood-Brain Barriers and Blood-Brain Interfaces: Bases for Physiological Regulation, Disease States, and Pharmacological Interventions. Pharmacol Rev 2018; 70:278-314. [PMID: 29496890 PMCID: PMC5833009 DOI: 10.1124/pr.117.014647] [Citation(s) in RCA: 198] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Central nervous system (CNS) barriers predominantly mediate the immune-privileged status of the brain, and are also important regulators of neuroimmune communication. It is increasingly appreciated that communication between the brain and immune system contributes to physiologic processes, adaptive responses, and disease states. In this review, we discuss the highly specialized features of brain barriers that regulate neuroimmune communication in health and disease. In section I, we discuss the concept of immune privilege, provide working definitions of brain barriers, and outline the historical work that contributed to the understanding of CNS barrier functions. In section II, we discuss the unique anatomic, cellular, and molecular characteristics of the vascular blood-brain barrier (BBB), blood-cerebrospinal fluid barrier, and tanycytic barriers that confer their functions as neuroimmune interfaces. In section III, we consider BBB-mediated neuroimmune functions and interactions categorized as five neuroimmune axes: disruption, responses to immune stimuli, uptake and transport of immunoactive substances, immune cell trafficking, and secretions of immunoactive substances. In section IV, we discuss neuroimmune functions of CNS barriers in physiologic and disease states, as well as pharmacological interventions for CNS diseases. Throughout this review, we highlight many recent advances that have contributed to the modern understanding of CNS barriers and their interface functions.
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Affiliation(s)
- Michelle A Erickson
- Geriatric Research and Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, Washington; and Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, Washington
| | - William A Banks
- Geriatric Research and Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, Washington; and Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, Washington
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27
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Shuvaev VV, Kiseleva RY, Arguiri E, Villa CH, Muro S, Christofidou-Solomidou M, Stan RV, Muzykantov VR. Targeting superoxide dismutase to endothelial caveolae profoundly alleviates inflammation caused by endotoxin. J Control Release 2017; 272:1-8. [PMID: 29292038 DOI: 10.1016/j.jconrel.2017.12.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 11/16/2017] [Accepted: 12/21/2017] [Indexed: 02/07/2023]
Abstract
Inflammatory mediators binding to Toll-Like receptors (TLR) induce an influx of superoxide anion in the ensuing endosomes. In endothelial cells, endosomal surplus of superoxide causes pro-inflammatory activation and TLR4 agonists act preferentially via caveolae-derived endosomes. To test the hypothesis that SOD delivery to caveolae may specifically inhibit this pathological pathway, we conjugated SOD with antibodies (Ab/SOD, size ~10nm) to plasmalemmal vesicle-associated protein (Plvap) that is specifically localized to endothelial caveolae in vivo and compared its effects to non-caveolar target CD31/PECAM-1. Plvap Ab/SOD bound to endothelial cells in culture with much lower efficacy than CD31 Ab/SOD, yet blocked the effects of LPS signaling with higher efficiency than CD31 Ab/SOD. Disruption of cholesterol-rich membrane domains by filipin inhibits Plvap Ab/SOD endocytosis and LPS signaling, implicating the caveolae-dependent pathway(s) in both processes. Both Ab/SOD conjugates targeted to Plvap and CD31 accumulated in the lungs after IV injection in mice, but the former more profoundly inhibited LPS-induced pulmonary inflammation and elevation of plasma level of interferon-beta and -gamma and interleukin-27. Taken together, these results indicate that targeted delivery of SOD to specific cellular compartments may offer effective, mechanistically precise interception of pro-inflammatory signaling mediated by reactive oxygen species.
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Affiliation(s)
- Vladimir V Shuvaev
- Department of Pharmacology, Center for Translational Targeted Therapeutics, Nanomedicine of the Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
| | - Raisa Yu Kiseleva
- Department of Pharmacology, Center for Translational Targeted Therapeutics, Nanomedicine of the Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
| | - Evguenia Arguiri
- Department of Medicine, Pulmonary, Allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States
| | - Carlos H Villa
- Department of Pharmacology, Center for Translational Targeted Therapeutics, Nanomedicine of the Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States
| | - Silvia Muro
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, United States
| | - Melpo Christofidou-Solomidou
- Department of Medicine, Pulmonary, Allergy and Critical Care Division, University of Pennsylvania, Philadelphia, PA, United States
| | - Radu V Stan
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH, United States
| | - Vladimir R Muzykantov
- Department of Pharmacology, Center for Translational Targeted Therapeutics, Nanomedicine of the Institute for Translational Medicine and Therapeutics, University of Pennsylvania, Philadelphia, PA, United States.
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28
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Kenig-Kozlovsky Y, Scott RP, Onay T, Carota IA, Thomson BR, Gil HJ, Ramirez V, Yamaguchi S, Tanna CE, Heinen S, Wu C, Stan RV, Klein JD, Sands JM, Oliver G, Quaggin SE. Ascending Vasa Recta Are Angiopoietin/Tie2-Dependent Lymphatic-Like Vessels. J Am Soc Nephrol 2017; 29:1097-1107. [PMID: 29237738 DOI: 10.1681/asn.2017090962] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/07/2017] [Indexed: 12/23/2022] Open
Abstract
Urinary concentrating ability is central to mammalian water balance and depends on a medullary osmotic gradient generated by a countercurrent multiplication mechanism. Medullary hyperosmolarity is protected from washout by countercurrent exchange and efficient removal of interstitial fluid resorbed from the loop of Henle and collecting ducts. In most tissues, lymphatic vessels drain excess interstitial fluid back to the venous circulation. However, the renal medulla is devoid of classic lymphatics. Studies have suggested that the fenestrated ascending vasa recta (AVRs) drain the interstitial fluid in this location, but this function has not been conclusively shown. We report that late gestational deletion of the angiopoietin receptor endothelial tyrosine kinase 2 (Tie2) or both angiopoietin-1 and angiopoietin-2 prevents AVR formation in mice. The absence of AVR associated with rapid accumulation of fluid and cysts in the medullary interstitium, loss of medullary vascular bundles, and decreased urine concentrating ability. In transgenic reporter mice with normal angiopoietin-Tie2 signaling, medullary AVR exhibited an unusual hybrid endothelial phenotype, expressing lymphatic markers (prospero homeobox protein 1 and vascular endothelial growth factor receptor 3) as well as blood endothelial markers (CD34, endomucin, platelet endothelial cell adhesion molecule 1, and plasmalemmal vesicle-associated protein). Taken together, our data redefine the AVRs as Tie2 signaling-dependent specialized hybrid vessels and provide genetic evidence of the critical role of AVR in the countercurrent exchange mechanism and the structural integrity of the renal medulla.
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Affiliation(s)
- Yael Kenig-Kozlovsky
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Rizaldy P Scott
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Tuncer Onay
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Isabel Anna Carota
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Benjamin R Thomson
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Hyea Jin Gil
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Veronica Ramirez
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Shinji Yamaguchi
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Christine E Tanna
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Stefan Heinen
- Sunnybrook Research Institute, Sunnybrook Hospital, Toronto, Ontario, Canada
| | - Christine Wu
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Radu V Stan
- Departments of Biochemistry and Cell Biology and.,Pathology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire; and
| | - Janet D Klein
- Division of Renal Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Jeff M Sands
- Division of Renal Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Guillermo Oliver
- Division of Nephrology and Hypertension and.,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Susan E Quaggin
- Division of Nephrology and Hypertension and .,Feinberg Cardiovascular Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
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Andrés-Guerrero V, García-Feijoo J, Konstas AG. Targeting Schlemm's Canal in the Medical Therapy of Glaucoma: Current and Future Considerations. Adv Ther 2017; 34:1049-1069. [PMID: 28349508 PMCID: PMC5427152 DOI: 10.1007/s12325-017-0513-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Indexed: 11/23/2022]
Abstract
Schlemm’s canal (SC) is a unique, complex vascular structure responsible for maintaining fluid homeostasis within the anterior segment of the eye by draining the excess of aqueous humour. In glaucoma, a heterogeneous group of eye disorders afflicting approximately 60 million individuals worldwide, the normal outflow of aqueous humour into SC is progressively hindered, leading to a gradual increase in outflow resistance, which gradually results in elevated intraocular pressure (IOP). By and large available antiglaucoma therapies do not target the site of the pathology (SC), but rather aim to decrease IOP by other mechanisms, either reducing aqueous production or by diverting aqueous flow through the unconventional outflow system. The present review first outlines our current understanding on the functional anatomy of SC. It then summarizes existing research on SC cell properties; first in the context of their role in glaucoma development/progression and then as a target of novel and emerging antiglaucoma therapies. Evidence from ongoing research efforts to develop effective antiglaucoma therapies targeting SC suggests that this could become a promising site of future therapeutic interventions.
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Caveolin-1 modulates intraocular pressure: implications for caveolae mechanoprotection in glaucoma. Sci Rep 2016; 6:37127. [PMID: 27841369 PMCID: PMC5107904 DOI: 10.1038/srep37127] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 10/25/2016] [Indexed: 12/11/2022] Open
Abstract
Polymorphisms in the CAV1/2 genes that encode signature proteins of caveolae are associated with glaucoma, the second leading cause of blindness worldwide, and with its major risk factor, intraocular pressure (IOP). We hypothesized that caveolin-1 (Cav-1) participates in IOP maintenance via modulation of aqueous humor drainage from the eye. We localize caveolae proteins to human and murine conventional drainage tissues and show that caveolae respond to mechanical stimulation. We show that Cav-1-deficient (Cav-1−/−) mice display ocular hypertension explained by reduced pressure-dependent drainage of aqueous humor. Cav-1 deficiency results in loss of caveolae in the Schlemm’s canal (SC) and trabecular meshwork. However, their absence did not appear to impact development nor adult form of the conventional outflow tissues according to rigorous quantitative ultrastructural analyses, but did affect cell and tissue behavior. Thus, when IOP is experimentally elevated, cells of the Cav-1−/− outflow tissues are more susceptible to plasma membrane rupture indicating that caveolae play a role in mechanoprotection. Additionally, aqueous drainage from Cav-1−/− eyes was more sensitive to nitric oxide (NO) synthase inhibition than controls, suggesting that excess NO partially compensates for outflow pathway dysfunction. These results provide a functional link between a glaucoma risk gene and glaucoma-relevant pathophysiology.
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31
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Elgueta R, Tse D, Deharvengt SJ, Luciano MR, Carriere C, Noelle RJ, Stan RV. Endothelial Plasmalemma Vesicle-Associated Protein Regulates the Homeostasis of Splenic Immature B Cells and B-1 B Cells. THE JOURNAL OF IMMUNOLOGY 2016; 197:3970-3981. [PMID: 27742829 DOI: 10.4049/jimmunol.1501859] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 09/18/2016] [Indexed: 12/18/2022]
Abstract
Plasmalemma vesicle-associated protein (Plvap) is an endothelial protein with roles in endothelial diaphragm formation and maintenance of basal vascular permeability. At the same time, Plvap has roles in immunity by facilitating leukocyte diapedesis at inflammatory sites and controlling peripheral lymph node morphogenesis and the entry of soluble Ags into lymph node conduits. Based on its postulated role in diapedesis, we have investigated the role of Plvap in hematopoiesis and show that deletion of Plvap results in a dramatic decrease of IgM+IgDlo B cells in both the spleen and the peritoneal cavity. Tissue-specific deletion of Plvap demonstrates that the defect is B cell extrinsic, because B cell and pan-hematopoietic Plvap deletion has no effect on IgM+IgDlo B cell numbers. Endothelial-specific deletion of Plvap in the embryo or at adult stage recapitulates the full Plvap knockout phenotype, whereas endothelial-specific reconstitution of Plvap under the Chd5 promoter rescues the IgM+IgDlo B cell phenotype. Taken together, these results show that Plvap expression in endothelial cells is important in the maintenance of IgM+ B cells in the spleen and peritoneal cavity.
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Affiliation(s)
- Raul Elgueta
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756.,Department of Immune Regulation and Intervention, Medical Research Council Centre for Transplantation, King's College London, Guy's Hospital, London, SE1 9RT, United Kingdom
| | - Dan Tse
- Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - Sophie J Deharvengt
- Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - Marcus R Luciano
- Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
| | - Catherine Carriere
- Department of Medicine, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756.,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756; and
| | - Randolph J Noelle
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; .,Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth and Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756; and
| | - Radu V Stan
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; .,Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756.,Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756
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32
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Epithelial-mesenchymal transition of the retinal pigment epithelium causes choriocapillaris atrophy. Histochem Cell Biol 2016; 146:769-780. [PMID: 27372654 DOI: 10.1007/s00418-016-1461-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2016] [Indexed: 12/11/2022]
Abstract
Epithelial-to-mesenchymal transition (EMT) of the retinal pigment epithelium (RPE) is commonly observed at sites of choroidal neovascularization in patients suffering from age-related macular degeneration. To learn in an experimental model how RPE EMT affects the biology of the choroidal vasculature, we studied transgenic mice (βB1-TGF-β1) with ocular overexpression of transforming growth factor-β1 (TGF-β1). RPE EMT was detectable at postnatal day (P)1 and included marked structural and functional alterations such as loss of the outer blood-retina barrier and reduced mRNA expression of the RPE-characteristic molecules Rlbp1, Rpe65, Rbp1 and Vegfa. Moreover, vascular endothelial growth factor (VEGF) was not detectable by immunohistochemistry at the RPE/choroid interface, while RPE cells stained intensely for α-smooth muscle actin. The choriocapillaris, the characteristic choroidal capillary network adjacent to the RPE, developed normally and was not obviously changed in embryonic transgenic eyes but was absent at P1 indicating its atrophy. At around the same time, photoreceptors stopped to differentiate and photoreceptor apoptosis was abundant in the second week of life. Structural changes were also seen in the retinal vasculature of transgenic animals, which did not form intraretinal vessels, and the hyaloid vasculature, which did not regress. In addition, the amounts of retinal HIF-1α and its mRNA were markedly reduced. We conclude that high amounts of active TGF-β1 in the mouse eye cause transdifferentiation of the RPE to a mesenchymal phenotype. The loss of epithelial differentiation leads to the diminished synthesis of RPE-characteristic molecules including that of VEGF. Lack of RPE-derived VEGF causes atrophy of the choriocapillaris, a scenario that disrupts photoreceptor differentiation and finally results in photoreceptor apoptosis. Lack of retinal vessel formation and of hyaloid vessel regression might be caused by the decrease in the metabolic requirements of the neuroretina leading to low amounts of retinal HIF-1α. In summary, our data indicate that failure of RPE differentiation may well precede and cause atrophy of the choriocapillaris. In contrast, RPE EMT is not sufficient to cause choroidal neovascularization.
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Dautriche CN, Tian Y, Xie Y, Sharfstein ST. A Closer Look at Schlemm's Canal Cell Physiology: Implications for Biomimetics. J Funct Biomater 2015; 6:963-85. [PMID: 26402712 PMCID: PMC4598687 DOI: 10.3390/jfb6030963] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/10/2015] [Accepted: 09/06/2015] [Indexed: 12/13/2022] Open
Abstract
Among ocular pathologies, glaucoma is the second leading cause of progressive vision loss, expected to affect 80 million people worldwide by 2020. A primary cause of glaucoma appears to be damage to the conventional outflow tract. Conventional outflow tissues, a composite of the trabecular meshwork and the Schlemm's canal, regulate and maintain homeostatic responses to intraocular pressure. In glaucoma, filtration of aqueous humor into the Schlemm's canal is hindered, leading to an increase in intraocular pressure and subsequent damage to the optic nerve, with progressive vision loss. The Schlemm's canal encompasses a unique endothelium. Recent advances in culturing and manipulating Schlemm's canal cells have elucidated several aspects of their physiology, including ultrastructure, cell-specific marker expression, and biomechanical properties. This review highlights these advances and discusses implications for engineering a 3D, biomimetic, in vitro model of the Schlemm's canal endothelium to further advance glaucoma research, including drug testing and gene therapy screening.
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Affiliation(s)
- Cula N Dautriche
- State University of New York (SUNY) Polytechnic Institute, Colleges of Nanoscale Science and Engineering, 257 Fuller Road, Albany, NY 12203, USA.
| | - Yangzi Tian
- State University of New York (SUNY) Polytechnic Institute, Colleges of Nanoscale Science and Engineering, 257 Fuller Road, Albany, NY 12203, USA.
| | - Yubing Xie
- State University of New York (SUNY) Polytechnic Institute, Colleges of Nanoscale Science and Engineering, 257 Fuller Road, Albany, NY 12203, USA.
| | - Susan T Sharfstein
- State University of New York (SUNY) Polytechnic Institute, Colleges of Nanoscale Science and Engineering, 257 Fuller Road, Albany, NY 12203, USA.
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Elkadri A, Thoeni C, Deharvengt SJ, Murchie R, Guo C, Stavropoulos JD, Marshall CR, Wales P, Bandsma RH, Cutz E, Roifman CM, Chitayat D, Avitzur Y, Stan RV, Muise AM. Mutations in Plasmalemma Vesicle Associated Protein Result in Sieving Protein-Losing Enteropathy Characterized by Hypoproteinemia, Hypoalbuminemia, and Hypertriglyceridemia. Cell Mol Gastroenterol Hepatol 2015; 1. [PMID: 26207260 PMCID: PMC4507283 DOI: 10.1016/j.jcmgh.2015.05.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS METHODS Severe intestinal diseases observed in very young children are often the result of monogenic defects. We used whole exome sequencing (WES) to examine the genetic cause in a patient with a distinct severe form of protein losing enteropathy (PLE) characterized by hypoproteinemia, hypoalbuminemia, and hypertriglyceridemia. METHODS WES was performed at the Centre for Applied Genomics, Hospital for Sick Children, Toronto, Canada. Exome library preparation was performed using the Ion Torrent AmpliSeq RDY Exome Kit. Functional studies were carried out based on the identified mutation. RESULTS Using whole exome sequencing we identified a homozygous nonsense mutation (1072C>T; p.Arg358*) in the PLVAP (plasmalemma vesicle associated protein) gene in an infant from consanguineous parents who died at five months of age of severe protein losing enteropathy. Functional studies determined that the mutated PLVAP mRNA and protein were not expressed in the patient biopsy tissues, presumably secondary to nonsense-mediated mRNA decay. Pathological analysis showed that the loss of PLVAP resulted in disruption of endothelial fenestrated diaphragms. CONCLUSIONS PLVAP p.Arg358* mutation resulted in loss of PLVAP expression with subsequent deletion of the diaphragms of endothelial fenestrae leading to plasma protein extravasation, protein-losing enteropathy and ultimately death.
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Affiliation(s)
- Abdul Elkadri
- SickKids Inflammatory Bowel Disease Center and Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada,Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Cornelia Thoeni
- SickKids Inflammatory Bowel Disease Center and Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada,Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sophie J. Deharvengt
- Department of Pathology, Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Ryan Murchie
- SickKids Inflammatory Bowel Disease Center and Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada,Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Conghui Guo
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - James D. Stavropoulos
- Genome Diagnostics, Department of Paediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Christian R. Marshall
- Genome Diagnostics, Department of Paediatric Laboratory Medicine, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Paul Wales
- Group for Improvement of Intestinal Function and Treatment (GIFT), Hospital for Sick Children, Toronto, Ontario, Canada
| | - Robert H.J. Bandsma
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ernest Cutz
- Division of Pathology, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Chaim M. Roifman
- Division of Immunology, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - David Chitayat
- Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yaron Avitzur
- Group for Improvement of Intestinal Function and Treatment (GIFT), Hospital for Sick Children, Toronto, Ontario, Canada
| | - Radu V. Stan
- Department of Pathology, Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Aleixo M. Muise
- SickKids Inflammatory Bowel Disease Center and Cell Biology Program, Research Institute, Hospital for Sick Children, Toronto, Ontario, Canada,Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of Toronto, Hospital for Sick Children, Toronto, Ontario, Canada,Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada,Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada,Correspondence Address correspondence to: Aleixo Muise, MD, PhD, 555 University Avenue, Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8. fax: (416) 813-6531.
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The aqueous humor outflow pathways in glaucoma: A unifying concept of disease mechanisms and causative treatment. Eur J Pharm Biopharm 2015; 95:173-81. [PMID: 25957840 DOI: 10.1016/j.ejpb.2015.04.029] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 04/24/2015] [Accepted: 04/29/2015] [Indexed: 12/28/2022]
Abstract
Intraocular pressure (IOP) is the critical risk factor for glaucoma, a neurodegenerative disease and frequent cause of blindness worldwide. As of today, all effective strategies to treat glaucoma aim at lowering IOP. IOP is generated and maintained via the aqueous humor circulation system in the anterior eye. Aqueous humor is secreted by the ciliary processes and exits the eye through the trabecular meshwork (TM) or the uveoscleral outflow pathways. The TM outflow pathways provide resistance to aqueous humor outflow and IOP builds up in response to it. In the normal eye, the resistance is localized in the inner wall region, which comprises the juxtacanalicular connective tissue (JCT) and the inner wall endothelium of Schlemm's canal (SC). Outflow resistance in the inner wall region is lowered through the contraction of the ciliary muscle or the relaxation of contractile myofibroblasts in the posterior part of the TM and the adjacent scleral spur. Patients with primary open-angle glaucoma (POAG), the most frequent form of glaucoma, typically suffer from an abnormally high outflow resistance of the inner wall region. There is increasing evidence that the increase in TM outflow resistance in POAG is the result of a characteristic change in the biological properties of the resident cells in the JCT, which increasingly acquire the phenotype of contractile myofibroblasts. This scenario strengthens simultaneously both their actin cytoskeleton and their directly associated extracellular matrix fibrils, leads to overall stiffening of the tissue, and is modulated by transforming growth factor-β (TGF-β)/connective tissue growth factor (CTGF) signaling. Essentially comparable changes appear to occur in SC endothelial cells in glaucoma. Causative therapy concepts targeting the aqueous outflow pathways in glaucoma should aim at interfering with this process either by attenuating TM or SC stiffness, and/or by modulating TGF-β/CTGF signaling.
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36
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Intraocular Pressure and the Mechanisms Involved in Resistance of the Aqueous Humor Flow in the Trabecular Meshwork Outflow Pathways. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 134:301-14. [DOI: 10.1016/bs.pmbts.2015.06.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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37
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Herrnberger L, Hennig R, Kremer W, Hellerbrand C, Goepferich A, Kalbitzer HR, Tamm ER. Formation of fenestrae in murine liver sinusoids depends on plasmalemma vesicle-associated protein and is required for lipoprotein passage. PLoS One 2014; 9:e115005. [PMID: 25541982 PMCID: PMC4277272 DOI: 10.1371/journal.pone.0115005] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 11/17/2014] [Indexed: 12/11/2022] Open
Abstract
Liver sinusoidal endothelial cells (LSEC) are characterized by the presence of fenestrations that are not bridged by a diaphragm. The molecular mechanisms that control the formation of the fenestrations are largely unclear. Here we report that mice, which are deficient in plasmalemma vesicle-associated protein (PLVAP), develop a distinct phenotype that is caused by the lack of sinusoidal fenestrations. Fenestrations with a diaphragm were not observed in mouse LSEC at three weeks of age, but were present during embryonic life starting from embryonic day 12.5. PLVAP was expressed in LSEC of wild-type mice, but not in that of Plvap-deficient littermates. Plvap-/- LSEC showed a pronounced and highly significant reduction in the number of fenestrations, a finding, which was seen both by transmission and scanning electron microscopy. The lack of fenestrations was associated with an impaired passage of macromolecules such as FITC-dextran and quantum dot nanoparticles from the sinusoidal lumen into Disse's space. Plvap-deficient mice suffered from a pronounced hyperlipoproteinemia as evidenced by milky plasma and the presence of lipid granules that occluded kidney and liver capillaries. By NMR spectroscopy of plasma, the nature of hyperlipoproteinemia was identified as massive accumulation of chylomicron remnants. Plasma levels of low density lipoproteins (LDL) were also significantly increased as were those of cholesterol and triglycerides. In contrast, plasma levels of high density lipoproteins (HDL), albumin and total protein were reduced. At around three weeks of life, Plvap-deficient livers developed extensive multivesicular steatosis, steatohepatitis, and fibrosis. PLVAP is critically required for the formation of fenestrations in LSEC. Lack of fenestrations caused by PLVAP deficiency substantially impairs the passage of chylomicron remnants between liver sinusoids and hepatocytes, and finally leads to liver damage.
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Affiliation(s)
- Leonie Herrnberger
- Department of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Robert Hennig
- Department of Pharmaceutical Technology, University of Regensburg, Regensburg, Germany
| | - Werner Kremer
- Department of Biophysics and Physical Biochemistry, and Centre of Magnetic Resonance in Chemistry and Biomedicine, University of Regensburg, Regensburg, Germany
| | - Claus Hellerbrand
- Department of Internal Medicine I, University Hospital Regensburg, Regensburg, Germany
| | - Achim Goepferich
- Department of Pharmaceutical Technology, University of Regensburg, Regensburg, Germany
| | - Hans Robert Kalbitzer
- Department of Biophysics and Physical Biochemistry, and Centre of Magnetic Resonance in Chemistry and Biomedicine, University of Regensburg, Regensburg, Germany
| | - Ernst R. Tamm
- Department of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
- * E-mail:
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Braakman ST, Pedrigi RM, Read AT, Smith JAE, Stamer WD, Ethier CR, Overby DR. Biomechanical strain as a trigger for pore formation in Schlemm's canal endothelial cells. Exp Eye Res 2014; 127:224-35. [PMID: 25128579 PMCID: PMC4175173 DOI: 10.1016/j.exer.2014.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 08/01/2014] [Accepted: 08/05/2014] [Indexed: 02/08/2023]
Abstract
The bulk of aqueous humor passing through the conventional outflow pathway must cross the inner wall endothelium of Schlemm's canal (SC), likely through micron-sized transendothelial pores. SC pore density is reduced in glaucoma, possibly contributing to obstructed aqueous humor outflow and elevated intraocular pressure (IOP). Little is known about the mechanisms of pore formation; however, pores are often observed near dome-like cellular outpouchings known as giant vacuoles (GVs) where significant biomechanical strain acts on SC cells. We hypothesize that biomechanical strain triggers pore formation in SC cells. To test this hypothesis, primary human SC cells were isolated from three non-glaucomatous donors (aged 34, 44 and 68), and seeded on collagen-coated elastic membranes held within a membrane stretching device. Membranes were then exposed to 0%, 10% or 20% equibiaxial strain, and the cells were aldehyde-fixed 5 min after the onset of strain. Each membrane contained 3-4 separate monolayers of SC cells as replicates (N = 34 total monolayers), and pores were assessed by scanning electron microscopy in 12 randomly selected regions (∼65,000 μm(2) per monolayer). Pores were identified and counted by four independent masked observers. Pore density increased with strain in all three cell lines (p < 0.010), increasing from 87 ± 36 pores/mm(2) at 0% strain to 342 ± 71 at 10% strain; two of the three cell lines showed no additional increase in pore density beyond 10% strain. Transcellular "I-pores" and paracellular "B-pores" both increased with strain (p < 0.038), however B-pores represented the majority (76%) of pores. Pore diameter, in contrast, appeared unaffected by strain (p = 0.25), having a mean diameter of 0.40 μm for I-pores (N = 79 pores) and 0.67 μm for B-pores (N = 350 pores). Pore formation appears to be a mechanosensitive process that is triggered by biomechanical strain, suggesting that SC cells have the ability to modulate local pore density and filtration characteristics of the inner wall endothelium based on local biomechanical cues. The molecular mechanisms of pore formation and how they become altered in glaucoma may be studied in vitro using stretched SC cells.
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Affiliation(s)
- Sietse T Braakman
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Ryan M Pedrigi
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - A Thomas Read
- Department of Ophthalmology and Vision Sciences, University of Toronto, Canada
| | - James A E Smith
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - W Daniel Stamer
- Department of Ophthalmology, Duke University Medical School, USA
| | - C Ross Ethier
- Department of Bioengineering, Imperial College London, London, United Kingdom; Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA
| | - Darryl R Overby
- Department of Bioengineering, Imperial College London, London, United Kingdom.
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39
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Aga M, Bradley JM, Wanchu R, Yang YF, Acott TS, Keller KE. Differential effects of caveolin-1 and -2 knockdown on aqueous outflow and altered extracellular matrix turnover in caveolin-silenced trabecular meshwork cells. Invest Ophthalmol Vis Sci 2014; 55:5497-509. [PMID: 25103269 DOI: 10.1167/iovs.14-14519] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
PURPOSE A single nucleotide polymorphism (SNP) identified between caveolin-1 (CAV1) and caveolin-2 (CAV2) on chromosome 7 is associated with glaucoma. One function of CAVs is endocytosis and recycling of extracellular matrix (ECM) components. Here, we generated CAV-silencing lentivirus to evaluate the effects on ECM turnover by trabecular meshwork (TM) cells and to measure the effect on outflow facility in anterior segment perfusion culture. METHODS Short hairpin CAV1 and CAV2 silencing and control lentivirus were generated, characterized, and applied to anterior segments in perfusion culture. Colocalization of CAVs with various ECM molecules in TM cells was investigated using immunofluorescence and confocal microscopy. Western immunoblotting and fluorogenic-based enzyme activity assays were used to investigate ECM protein levels and degradation, respectively. RESULTS Endogenous CAVs colocalized with cortactin at podosome- or invadopodia-like structures (PILS), which are areas of focal ECM degradation. In perfusion culture, outflow rates increased significantly in CAV1-silenced anterior segments, whereas outflow significantly decreased in CAV2-silenced anterior segments. Matrix metalloproteinase (MMP)2 and MMP14, and a disintegrin and metalloproteinase with thrombospondin motifs-4 (ADAMTS4) colocalized with both CAVs in TM cells. Protein levels and enzyme activities of MMP/ADAMTS4, fibronectin protein levels, actin stress fibers, and α-smooth muscle actin were all increased in CAV-silenced cells. CONCLUSIONS Caveolin-mediated endocytosis is one mechanism by which TM cells can alter the physiological catabolism of ECM in order to change the composition of the outflow channels in the TM to regulate aqueous outflow resistance. Dysregulation of CAV function could contribute to the pathological changes in ECM that are observed in glaucoma.
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Affiliation(s)
- Mini Aga
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - John M Bradley
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Rohan Wanchu
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Yong-feng Yang
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Ted S Acott
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Kate E Keller
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
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Funktionelle Morphologie der Abflusswege des Kammerwassers und ihre Veränderungen beim Offenwinkelglaukom. Ophthalmologe 2013; 110:1026-35. [DOI: 10.1007/s00347-012-2670-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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41
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Stan RV, Tse D, Deharvengt SJ, Smits NC, Xu Y, Luciano MR, McGarry CL, Buitendijk M, Nemani KV, Elgueta R, Kobayashi T, Shipman SL, Moodie KL, Daghlian CP, Ernst PA, Lee HK, Suriawinata AA, Schned AR, Longnecker DS, Fiering SN, Noelle RJ, Gimi B, Shworak NW, Carrière C. The diaphragms of fenestrated endothelia: gatekeepers of vascular permeability and blood composition. Dev Cell 2012; 23:1203-18. [PMID: 23237953 PMCID: PMC3525343 DOI: 10.1016/j.devcel.2012.11.003] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2011] [Revised: 09/07/2012] [Accepted: 11/11/2012] [Indexed: 11/21/2022]
Abstract
Fenestral and stomatal diaphragms are endothelial subcellular structures of unknown function that form on organelles implicated in vascular permeability: fenestrae, transendothelial channels, and caveolae. PV1 protein is required for diaphragm formation in vitro. Here, we report that deletion of the PV1-encoding Plvap gene in mice results in the absence of diaphragms and decreased survival. Loss of diaphragms did not affect the fenestrae and transendothelial channels formation but disrupted the barrier function of fenestrated capillaries, causing a major leak of plasma proteins. This disruption results in early death of animals due to severe noninflammatory protein-losing enteropathy. Deletion of PV1 in endothelium, but not in the hematopoietic compartment, recapitulates the phenotype of global PV1 deletion, whereas endothelial reconstitution of PV1 rescues the phenotype. Taken together, these data provide genetic evidence for the critical role of the diaphragms in fenestrated capillaries in the maintenance of blood composition.
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Affiliation(s)
- Radu V Stan
- Department of Pathology, Geisel School of Medicine at Dartmouth, Hanover, NH 03756, USA.
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