1
|
Agafonova A, Cosentino A, Romano IR, Giurdanella G, D’Angeli F, Giuffrida R, Lo Furno D, Anfuso CD, Mannino G, Lupo G. Molecular Mechanisms and Therapeutic Implications of Human Pericyte-like Adipose-Derived Mesenchymal Stem Cells in an In Vitro Model of Diabetic Retinopathy. Int J Mol Sci 2024; 25:1774. [PMID: 38339053 PMCID: PMC10855418 DOI: 10.3390/ijms25031774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/19/2024] [Accepted: 01/30/2024] [Indexed: 02/12/2024] Open
Abstract
The blood-retinal barrier (BRB) is strongly compromised in diabetic retinopathy (DR) due to the detachment of pericytes (PCs) from retinal microvessels, resulting in increased permeability and impairment of the BRB. Western blots, immunofluorescence and ELISA were performed on adipose mesenchymal stem cells (ASCs) and pericyte-like (P)-ASCs by co-cultured human retinal endothelial cells (HRECs) under hyperglycemic conditions (HG), as a model of DR. Our results demonstrated that: (a) platelet-derived growth factor receptor (PDGFR) and its activated form were more highly expressed in monocultured P-ASCs than in ASCs, and this expression increased when co-cultured with HRECs under high glucose conditions (HG); (b) the transcription factor Nrf2 was more expressed in the cytoplasmic fraction of ASCs and in the P-ASC nuclear fraction, under normal glucose and, even more, under HG conditions; (c) cytosolic phospholipase A2 activity and prostaglandin E2 release, stimulated by HG, were significantly reduced in P-ASCs co-cultured with HRECs; (d) HO-1 protein content was significantly higher in HG-P-ASCs/HRECs than P-ASCs/HRECs; and (e) VEGF-A levels in media from HG-co-cultures were reduced in P-ASCs/HRECs with respect to ASCs/HRECs. The data obtained highlighted the potential of autologous differentiated ASCs in future clinical applications based on cell therapy to counteract the damage induced by DR.
Collapse
Affiliation(s)
- Aleksandra Agafonova
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | - Alessia Cosentino
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | - Ivana Roberta Romano
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | | | - Floriana D’Angeli
- Department of Human Sciences and Quality of Life Promotion, San Raffaele Roma Open University, 00166 Rome, Italy;
| | - Rosario Giuffrida
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | - Debora Lo Furno
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | - Carmelina Daniela Anfuso
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| | - Giuliana Mannino
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98122 Messina, Italy;
| | - Gabriella Lupo
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95123 Catania, Italy; (A.A.); (A.C.); (I.R.R.); (R.G.); (G.L.)
| |
Collapse
|
2
|
Li Y, Cheng ZX, Luo T, Lyu HB. Therapeutic potential of iron chelators in retinal vascular diseases. Int J Ophthalmol 2023; 16:1899-1910. [PMID: 38028518 PMCID: PMC10626364 DOI: 10.18240/ijo.2023.11.24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 08/24/2023] [Indexed: 12/01/2023] Open
Abstract
Iron is one of the necessary metal elements in the human body. There are numerous factors that control the balance of iron metabolism, and its storage and transportation mechanisms are intricate. As one of the most energy-intensive tissues in the body, the retina is susceptible to iron imbalance. The occurrence of iron overload in the retina leads to the generation of a significant quantity of reactive oxygen species. This will aggravate local oxidative stress and inflammatory reactions and even lead to ferroptosis, eventually resulting in retinal dysfunction. The blood-retina-retinal barrier is eventually harmed by oxidative stress and elevated inflammation, which are characteristics of retinal vascular disorders. The pathophysiology of retinal vascular disorders may be significantly influenced by iron. Recently, iron-chelating agents have been found to have antioxidative and anti-inflammatory actions in addition to iron chelating. Therefore, iron neutralization is considered to be a new and potentially useful therapeutic strategy. This article reviews the iron overload in retinal vascular diseases and discusses the therapeutic potential of iron-chelating agents.
Collapse
Affiliation(s)
- Yan Li
- Department of Ophthalmology, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China
- Department of Ophthalmology, the People's Hospital of Jianyang, Chengdu 641400, Sichuan Province, China
| | - Zi-Xuan Cheng
- Department of Ophthalmology, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China
| | - Ting Luo
- Department of Ophthalmology, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China
- Department of Ophthalmology, the People's Hospital of Jianyang, Chengdu 641400, Sichuan Province, China
| | - Hong-Bin Lyu
- Department of Ophthalmology, the Affiliated Hospital of Southwest Medical University, Luzhou 646000, Sichuan Province, China
| |
Collapse
|
3
|
Amato R, Melecchi A, Pucci L, Canovai A, Marracci S, Cammalleri M, Dal Monte M, Caddeo C, Casini G. Liposome-Mediated Delivery Improves the Efficacy of Lisosan G against Retinopathy in Diabetic Mice. Cells 2023; 12:2448. [PMID: 37887292 PMCID: PMC10605070 DOI: 10.3390/cells12202448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/04/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
Nutraceuticals are natural substances whose anti-oxidant and anti-inflammatory properties may be used to treat retinal pathologies. Their efficacy is limited by poor bioavailability, which could be improved using nanocarriers. Lisosan G (LG), a fermented powder from whole grains, protects the retina from diabetic retinopathy (DR)-induced damage. For this study, we tested whether the encapsulation of LG in liposomes (LipoLG) may increase its protective effects. Diabetes was induced in mice via streptozotocin administration, and the mice were allowed to freely drink water or a water dispersion of two different doses of LG or of LipoLG. Electroretinographic recordings after 6 weeks showed that only the highest dose of LG could partially protect the retina from diabetes-induced functional deficits, while both doses of LipoLG were effective. An evaluation of molecular markers of oxidative stress, inflammation, apoptosis, vascular endothelial growth factor, and the blood-retinal barrier confirmed that the highest dose of LG only partially protected the retina from DR-induced changes, while virtually complete prevention was obtained with either dose of LipoLG. These data indicate that the efficacy of LG in contrasting DR is greatly enhanced by its encapsulation in liposomes and may lay the ground for new dietary supplements with improved therapeutic effects against DR.
Collapse
Affiliation(s)
- Rosario Amato
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Alberto Melecchi
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Laura Pucci
- Institute of Agricultural Biology and Biotechnology, National Research Council (CNR), 56124 Pisa, Italy;
| | - Alessio Canovai
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Silvia Marracci
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
| | - Maurizio Cammalleri
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
| | - Massimo Dal Monte
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
| | - Carla Caddeo
- Department of Life and Environmental Sciences, University of Cagliari, 09042 Cagliari, Italy
| | - Giovanni Casini
- Department of Biology, University of Pisa, 56126 Pisa, Italy; (R.A.); (A.M.); (A.C.); (S.M.); (M.C.); (M.D.M.)
- Interdepartmental Research Center Nutrafood “Nutraceuticals and Food for Health”, University of Pisa, 56124 Pisa, Italy
| |
Collapse
|
4
|
Bora K, Kushwah N, Maurya M, Pavlovich MC, Wang Z, Chen J. Assessment of Inner Blood-Retinal Barrier: Animal Models and Methods. Cells 2023; 12:2443. [PMID: 37887287 PMCID: PMC10605292 DOI: 10.3390/cells12202443] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 10/07/2023] [Accepted: 10/08/2023] [Indexed: 10/28/2023] Open
Abstract
Proper functioning of the neural retina relies on the unique retinal environment regulated by the blood-retinal barrier (BRB), which restricts the passage of solutes, fluids, and toxic substances. BRB impairment occurs in many retinal vascular diseases and the breakdown of BRB significantly contributes to disease pathology. Understanding the different molecular constituents and signaling pathways involved in BRB development and maintenance is therefore crucial in developing treatment modalities. This review summarizes the major molecular signaling pathways involved in inner BRB (iBRB) formation and maintenance, and representative animal models of eye diseases with retinal vascular leakage. Studies on Wnt/β-catenin signaling are highlighted, which is critical for retinal and brain vascular angiogenesis and barriergenesis. Moreover, multiple in vivo and in vitro methods for the detection and analysis of vascular leakage are described, along with their advantages and limitations. These pre-clinical animal models and methods for assessing iBRB provide valuable experimental tools in delineating the molecular mechanisms of retinal vascular diseases and evaluating therapeutic drugs.
Collapse
Affiliation(s)
| | | | | | | | | | - Jing Chen
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| |
Collapse
|
5
|
Díaz-Coránguez M, González-González L, Wang A, Liu X, Antonetti DA. Disheveled-1 Interacts with Claudin-5 and Contributes to Norrin-Induced Endothelial Barrier Restoration. Cells 2023; 12:2402. [PMID: 37830616 PMCID: PMC10571979 DOI: 10.3390/cells12192402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/27/2023] [Accepted: 09/29/2023] [Indexed: 10/14/2023] Open
Abstract
Previous studies have revealed that norrin can reverse vascular endothelial-growth-factor (VEGF)-induced permeability in a β-catenin-dependent pathway. Here, we have explored the contribution of disheveled-1 (DVL1) in norrin-induced blood-retinal barrier (BRB) restoration. We provide evidence that in addition to canonical signaling, DVL1 promotes tight junction (TJ) stabilization through a novel, non-canonical signaling pathway involving direct claudin-5 (CLDN5) binding. Immunofluorescence staining of rat retinal cross-sections showed enriched expression of DVL1 and 3 at endothelial capillaries and co-localization with CLDN5 and ZO-1 at the TJ complex in primary bovine retinal endothelial cells (BRECs). Barrier properties of BRECs were determined via measurements of trans-endothelial electrical resistance (TEER) or permeability to 70 kDa RITC-dextran. These studies demonstrated that norrin restoration of barrier properties after VEGF treatment required DVL1 as an siRNA knockdown of Dvl1 but not Dvl2 or Dvl3, reduced basal barrier properties and ablated norrin-induced barrier restoration. However, loss of Dvl1 did not decrease β-catenin signaling activity as measured by Axin2 mRNA expression, suggesting the contribution of a non-canonical pathway. DVL and TJ protein interactions were analyzed via co-immunoprecipitation of endogenous protein in BRECs, which demonstrated that DVL1 interacts with both CLDN5 and ZO-1, while DVL3 interacts only with ZO-1. These interactions were most abundant after inducing BRB restoration by treating BRECs with VEGF and norrin. DVL has previously been shown to form intramolecular bindings between the C-terminal PDZ-binding motif (PDZ-BM) with an internal PDZ domain. Co-transfection of HEK293 cells with DVL1 and CLDN5 or relevant mutants revealed that DVL1 interacts with CLDN5 through the DVL PDZ domain binding, CLDN5 PDZ-BM, in competition with DVL1 PDZ-BM, since DVL/CLDN5 interaction increases with deletion of the DVL1 PDZ-BM and decreases by co-expressing the C-terminal fragment of DVL1 containing the PDZ-BM or through deletion of CLDN5 PDZ-BM. In BREC cells, transfection of the C-terminal fragment of DVL1 downregulates the expression of CLDN5 but does not affect the expression of other proteins of the TJs, including ZO-1, occludin, CLDN1 or VE-cadherin. Blocking DVL1/CLDN5 interaction increased basal permeability and prevented norrin induction of barrier properties after VEGF. Combined with previous data, these results demonstrate that norrin signals through both a canonical β-catenin pathway and a non-canonical signaling pathway by which DVL1 directly binds to CLDN5 to promote barrier properties.
Collapse
Affiliation(s)
- Mónica Díaz-Coránguez
- Department of Pharmacobiology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 07360, Mexico;
| | - Laura González-González
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA; (L.G.-G.); (A.W.); (X.L.)
| | - Amy Wang
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA; (L.G.-G.); (A.W.); (X.L.)
| | - Xuwen Liu
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA; (L.G.-G.); (A.W.); (X.L.)
| | - David A. Antonetti
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Arbor, MI 48105, USA; (L.G.-G.); (A.W.); (X.L.)
| |
Collapse
|
6
|
Tega Y, Kubo Y, Miura H, Ri K, Tomise A, Akanuma SI, Hosoya KI. Carrier-Mediated Process of Putrescine Elimination at the Rat Blood-Retinal Barrier. Int J Mol Sci 2023; 24:ijms24109003. [PMID: 37240348 DOI: 10.3390/ijms24109003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
Putrescine is a bioactive polyamine. Its retinal concentration is strictly controlled to maintain a healthy sense of vision. The present study investigated putrescine transport at the blood-retinal barrier (BRB) to gain a better understanding of the mechanisms of putrescine regulation in the retina. Our microdialysis study showed that the elimination rate constant during the terminal phase was significantly greater (1.90-fold) than that of [14C]D-mannitol, which is a bulk flow marker. The difference in the apparent elimination rate constants of [3H]putrescine and [14C]D-mannitol was significantly decreased by unlabeled putrescine and spermine, suggesting active putrescine transport from the retina to the blood across the BRB. Our study using model cell lines of the inner and outer BRB showed that [3H]putrescine transport was time-, temperature-, and concentration-dependent, suggesting the involvement of carrier-mediated processes in putrescine transport at the inner and outer BRB. [3H]Putrescine transport was significantly reduced under Na+-free, Cl--free, and K+-replacement conditions, and attenuated by polyamines or organic cations such as choline, a choline transporter-like protein (CTL) substrate. Rat CTL1 cRNA-injected oocytes exhibited marked alterations in [3H]putrescine uptake, and CTL1 knockdown significantly reduced [3H]putrescine uptake in model cell lines, suggesting the possible participation of CTL1 in putrescine transport at the BRB.
Collapse
Affiliation(s)
- Yuma Tega
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Yoshiyuki Kubo
- Laboratory of Drug Disposition and Pharmacokinetics, Faculty of Pharma-Sciences, Teikyo University, Kaga 2-11-1, Tokyo 173-8605, Japan
| | - Hiroaki Miura
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Kairi Ri
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Ayaka Tomise
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Shin-Ichi Akanuma
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | - Ken-Ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| |
Collapse
|
7
|
Amato R, Cammalleri M, Melecchi A, Bagnoli P, Porciatti V. Natural History of Glaucoma Progression in the DBA/2J Model: Early Contribution of Müller Cell Gliosis. Cells 2023; 12:cells12091272. [PMID: 37174673 PMCID: PMC10177096 DOI: 10.3390/cells12091272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 04/21/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Glaucoma is a chronic optic neuropathy characterized by progressive degeneration of retinal ganglion cells (RGCs). Elevated intraocular pressure (IOP) and the resulting mechanical stress are classically considered the main causes of RGC death. However, RGC degeneration and ensuing vision loss often occur independent of IOP, indicating a multifactorial nature of glaucoma, with the likely contribution of glial and vascular function. The aim of the present study was to provide a comprehensive evaluation of the time course of neuro-glial-vascular changes associated with glaucoma progression. We used DBA/2J mice in the age range of 2-15 months as a spontaneous model of glaucoma with progressive IOP elevation and RGC loss typical of human open-angle glaucoma. We found that the onset of RGC degeneration at 10 months of age coincided with that of IOP elevation and vascular changes such as decreased density, increased lacunarity and decreased tight-junction protein zonula occludens (ZO)-1, while hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) were already significantly upregulated at 6 months of age together with the onset of Müller cell gliosis. Astrocytes, however, underwent significant gliosis at 10 months. These results indicate that Müller cell activation occurs well before IOP elevation, with probable inflammatory consequences, and represents an early event in the glaucomatous process. Early upregulation of HIF-1α and VEGF is likely to contribute to blood retinal barrier failure, facilitating RGC loss. The different time courses of neuro-glial-vascular changes during glaucoma progression provide further insight into the nature of the disease and suggest potential targets for the development of efficient therapeutic intervention aside from IOP lowering.
Collapse
Affiliation(s)
- Rosario Amato
- Department of Biology, University of Pisa, 56127 Pisa, Italy
| | | | | | - Paola Bagnoli
- Department of Biology, University of Pisa, 56127 Pisa, Italy
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| |
Collapse
|
8
|
Lupo G, Agafonova A, Cosentino A, Giurdanella G, Mannino G, Lo Furno D, Romano IR, Giuffrida R, D'Angeli F, Anfuso CD. Protective Effects of Human Pericyte-like Adipose-Derived Mesenchymal Stem Cells on Human Retinal Endothelial Cells in an In Vitro Model of Diabetic Retinopathy: Evidence for Autologous Cell Therapy. Int J Mol Sci 2023; 24. [PMID: 36674425 DOI: 10.3390/ijms24020913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/23/2022] [Accepted: 12/31/2022] [Indexed: 01/06/2023] Open
Abstract
Diabetic retinopathy (DR) is characterized by morphologic and metabolic alterations in endothelial cells (ECs) and pericytes (PCs) of the blood-retinal barrier (BRB). The loss of interendothelial junctions, increased vascular permeability, microaneurysms, and finally, EC detachment are the main features of DR. In this scenario, a pivotal role is played by the extensive loss of PCs. Based on previous results, the aim of this study was to assess possible beneficial effects exerted by adipose mesenchymal stem cells (ASCs) and their pericyte-like differentiated phenotype (P-ASCs) on human retinal endothelial cells (HRECs) in high glucose conditions (25 mM glucose, HG). P-ASCs were more able to preserve BRB integrity than ASCs in terms of (a) increased transendothelial electrical resistance (TEER); (b) increased expression of adherens junction and tight junction proteins (VE-cadherin and ZO-1); (c) reduction in mRNA levels of inflammatory cytokines TNF-α, IL-1β, and MMP-9; (d) reduction in the angiogenic factor VEGF and in fibrotic TGF-β1. Moreover, P-ASCs counteracted the HG-induced activation of the pro-inflammatory phospho-ERK1/2/phospho-cPLA2/COX-2 pathway. Finally, crosstalk between HRECs and ASCs or P-ASCs based on the PDGF-B/PDGFR-β axis at the mRNA level is described herein. Thus, P-ASCs might be considered valuable candidates for therapeutic approaches aimed at countering BRB disruption in DR.
Collapse
|
9
|
Wang Y, Yang X, Li Q, Zhang Y, Chen L, Hong L, Xie Z, Yang S, Deng X, Cao M, Yi G, Fu M. Single-cell RNA sequencing reveals the Müller subtypes and inner blood-retinal barrier regulatory network in early diabetic retinopathy. Front Mol Neurosci 2022; 15:1048634. [PMID: 36533134 PMCID: PMC9754943 DOI: 10.3389/fnmol.2022.1048634] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/10/2022] [Indexed: 11/30/2023] Open
Abstract
As the basic pathological changes of diabetic retinopathy (DR), the destruction of the blood-retina barrier (BRB) and vascular leakage have attracted extensive attention. Without timely intervention, BRB damage will eventually lead to serious visual impairment. However, due to the delicate structure and complex function of the BRB, the mechanism underlying damage to the BRB in DR has not been fully clarified. Here, we used single-cell RNA sequencing (RNA-seq) technology to analyze 35,910 cells from the retina of healthy and streptozotocin (STZ)-induced diabetic rats, focusing on the degeneration of the main cells constituting the rat BRB in DR and the new definition of two subpopulations of Müller cells at the cell level, Ctxn3 +Müller and Ctxn3 -Müller cells. We analyzed the characteristics and significant differences between the two groups of Müller cells and emphasized the importance of the Ctxn3 +Müller subgroup in diseases. In endothelial cells, we found possible mechanisms of self-protection and adhesion and recruitment to pericytes. In addition, we constructed a communication network between endothelial cells, pericytes, and Müller subsets and clarified the complex regulatory relationship between cells. In summary, we constructed an atlas of the iBRB in the early stage of DR and elucidate the degeneration of its constituent cells and Müller cells and the regulatory relationship between them, providing a series of potential targets for the early treatment of DR.
Collapse
Affiliation(s)
- Yan Wang
- Department of Ophthalmology, South China Hospital of Shenzhen University, Shenzhen, China
| | - Xiongyi Yang
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Qiumo Li
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Yuxi Zhang
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Lin Chen
- Department of Anesthesiology, Shenzhen Hospital, Southern Medical University, Shenzhen, Guangdong, China
| | - Libing Hong
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhuohang Xie
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Siyu Yang
- Department of Ophthalmology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen, China
| | - Xiaoqing Deng
- The Second Clinical School, Southern Medical University, Guangzhou, Guangdong, China
| | - Mingzhe Cao
- Department of Ophthalmology, The Seventh Affiliated Hospital, Sun Yat-Sen University, Shenzhen, China
| | - Guoguo Yi
- Department of Ophthalmology, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Min Fu
- Department of Ophthalmology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| |
Collapse
|
10
|
Lee YR, Son M, Kim YS, Kim JS, Kim CH, Jung SH. Evaluation of a Rapid and Simple Method for Assessing Retinal Vessel Structures in Adult Zebrafish. Int J Mol Sci 2022; 23:ijms232315069. [PMID: 36499406 PMCID: PMC9739661 DOI: 10.3390/ijms232315069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 11/26/2022] [Accepted: 11/29/2022] [Indexed: 12/04/2022] Open
Abstract
The evaluation of retinal vascular structures is important for analyzing various ophthalmic diseases. Conventional trypsin digestion was used for separating retinal vasculatures in mouse, rat, and other animal models; however, the trypsin method alone is technically difficult to perform and has not been reported in zebrafish to date. In this study, we introduced a rapid and convenient method that allows the investigation of fine vessel structures at a cellular level in the relatively intact retinal vasculature of adult zebrafish. Using an anti-ZO-1 antibody, tight junction structures in retinal vessels were examined in detail and several different cell types constituting blood vessels in arterial and capillary areas were identified. In addition, using cell type-specific antibodies, we identified smooth muscle cells, blood cells, and endothelial cells in the retinal vasculature. Finally, using the hyperglycemic model, we observed the dilation of retinal vessels, the downregulation of tight junction proteins, and the reduction in smooth muscle cells. Based on these results, we provide a rapid and convenient method for the study of retinal vasculature disease in the zebrafish animal model.
Collapse
Affiliation(s)
- Yu-Ri Lee
- Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Republic of Korea
- Department of Biology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Myeongjoo Son
- Research Institute for Aerospace Medicine, Inha University, Incheon 22212, Republic of Korea
| | - Young Sook Kim
- Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Republic of Korea
| | - Jin Sook Kim
- Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Republic of Korea
- Julia Laboratory, Suwon 16232, Republic of Korea
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon 34134, Republic of Korea
- Correspondence: (C.-H.K.); (S.-H.J.)
| | - Seung-Hyun Jung
- Korean Medicine Convergence Research Division, Korea Institute of Oriental Medicine (KIOM), Daejeon 34054, Republic of Korea
- Department of Genetic Resources, National Marine Biodiversity Institute of Korea (MABIK), Seocheon 33662, Republic of Korea
- Correspondence: (C.-H.K.); (S.-H.J.)
| |
Collapse
|
11
|
Stofkova A, Zloh M, Andreanska D, Fiserova I, Kubovciak J, Hejda J, Kutilek P, Murakami M. Depletion of Retinal Dopaminergic Activity in a Mouse Model of Rod Dysfunction Exacerbates Experimental Autoimmune Uveoretinitis: A Role for the Gateway Reflex. Int J Mol Sci 2021; 23:ijms23010453. [PMID: 35008877 PMCID: PMC8745287 DOI: 10.3390/ijms23010453] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/24/2021] [Accepted: 12/29/2021] [Indexed: 12/20/2022] Open
Abstract
The gateway reflex is a mechanism by which neural inputs regulate chemokine expression at endothelial cell barriers, thereby establishing gateways for the invasion of autoreactive T cells into barrier-protected tissues. In this study, we hypothesized that rod photoreceptor dysfunction causes remodeling of retinal neural activity, which influences the blood–retinal barrier and the development of retinal inflammation. We evaluated this hypothesis using Gnat1rd17 mice, a model of night blindness with late-onset rod-cone dystrophy, and experimental autoimmune uveoretinitis (EAU). Retinal remodeling and its effect on EAU development were investigated by transcriptome profiling, target identification, and functional validation. We showed that Gnat1rd17 mice primarily underwent alterations in their retinal dopaminergic system, triggering the development of an exacerbated EAU, which was counteracted by dopamine replacement with L-DOPA administered either systemically or locally. Remarkably, dopamine acted on retinal endothelial cells to inhibit NF-κB and STAT3 activity and the expression of downstream target genes such as chemokines involved in T cell recruitment. These results suggest that rod-mediated dopamine release functions in a gateway reflex manner in the homeostatic control of immune cell entry into the retina, and the loss of retinal dopaminergic activity in conditions associated with rod dysfunction increases the susceptibility to autoimmune uveitis.
Collapse
Affiliation(s)
- Andrea Stofkova
- Department of Physiology, Third Faculty of Medicine, Charles University, Ke Karlovu 4, 120 00 Prague, Czech Republic; (M.Z.); (D.A.); (I.F.)
- Correspondence: ; Tel.: +420-224-902-718
| | - Miloslav Zloh
- Department of Physiology, Third Faculty of Medicine, Charles University, Ke Karlovu 4, 120 00 Prague, Czech Republic; (M.Z.); (D.A.); (I.F.)
| | - Dominika Andreanska
- Department of Physiology, Third Faculty of Medicine, Charles University, Ke Karlovu 4, 120 00 Prague, Czech Republic; (M.Z.); (D.A.); (I.F.)
| | - Ivana Fiserova
- Department of Physiology, Third Faculty of Medicine, Charles University, Ke Karlovu 4, 120 00 Prague, Czech Republic; (M.Z.); (D.A.); (I.F.)
- Department of Pathophysiology, Third Faculty of Medicine, Charles University, Ruska 87, 100 00 Prague, Czech Republic
| | - Jan Kubovciak
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic;
| | - Jan Hejda
- Department of Health Care and Population Protection, Faculty of Biomedical Engineering, Czech Technical University in Prague, Sitna Sq. 3105, 272 01 Kladno, Czech Republic; (J.H.); (P.K.)
| | - Patrik Kutilek
- Department of Health Care and Population Protection, Faculty of Biomedical Engineering, Czech Technical University in Prague, Sitna Sq. 3105, 272 01 Kladno, Czech Republic; (J.H.); (P.K.)
| | - Masaaki Murakami
- Division of Molecular Psychoimmunology, Institute for Genetic Medicine and Graduate School of Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo 060-0815, Japan;
| |
Collapse
|
12
|
Yemanyi F, Bora K, Blomfield AK, Wang Z, Chen J. Wnt Signaling in Inner Blood-Retinal Barrier Maintenance. Int J Mol Sci 2021; 22:11877. [PMID: 34769308 PMCID: PMC8584977 DOI: 10.3390/ijms222111877] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 10/28/2021] [Accepted: 10/29/2021] [Indexed: 12/14/2022] Open
Abstract
The retina is a light-sensing ocular tissue that sends information to the brain to enable vision. The blood-retinal barrier (BRB) contributes to maintaining homeostasis in the retinal microenvironment by selectively regulating flux of molecules between systemic circulation and the retina. Maintaining such physiological balance is fundamental to visual function by facilitating the delivery of nutrients and oxygen and for protection from blood-borne toxins. The inner BRB (iBRB), composed mostly of inner retinal vasculature, controls substance exchange mainly via transportation processes between (paracellular) and through (transcellular) the retinal microvascular endothelium. Disruption of iBRB, characterized by retinal edema, is observed in many eye diseases and disturbs the physiological quiescence in the retina's extracellular space, resulting in vision loss. Consequently, understanding the mechanisms of iBRB formation, maintenance, and breakdown is pivotal to discovering potential targets to restore function to compromised physiological barriers. These unraveled targets can also inform potential drug delivery strategies across the BRB and the blood-brain barrier into retinas and brain tissues, respectively. This review summarizes mechanistic insights into the development and maintenance of iBRB in health and disease, with a specific focus on the Wnt signaling pathway and its regulatory role in both paracellular and transcellular transport across the retinal vascular endothelium.
Collapse
Affiliation(s)
| | | | | | | | - Jing Chen
- Department of Ophthalmology, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.Y.); (K.B.); (A.K.B.); (Z.W.)
| |
Collapse
|
13
|
Shinozaki Y, Akanuma SI, Mori Y, Kubo Y, Hosoya KI. Comprehensive Evidence of Carrier-Mediated Distribution of Amantadine to the Retina across the Blood-Retinal Barrier in Rats. Pharmaceutics 2021; 13:1339. [PMID: 34575415 DOI: 10.3390/pharmaceutics13091339] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/16/2021] [Accepted: 08/24/2021] [Indexed: 11/20/2022] Open
Abstract
Amantadine, a drug used for the blockage of NMDA receptors, is well-known to exhibit neuroprotective effects. Accordingly, assessment of amantadine transport at retinal barriers could result in the application of amantadine for retinal diseases such as glaucoma. The objective of this study was to elucidate the retinal distribution of amantadine across the inner and outer blood–retinal barrier (BRB). In vivo blood-to-retina [3H]amantadine transport was investigated by using the rat retinal uptake index method, which was significantly reduced by unlabeled amantadine. This result indicated the involvement of carrier-mediated processes in the retinal distribution of amantadine. In addition, in vitro model cells of the inner and outer BRB (TR-iBRB2 and RPE-J cells) exhibited saturable kinetics (Km in TR-iBRB2 cells, 79.4 µM; Km in RPE-J cells, 90.5 and 9830 µM). The inhibition of [3H]amantadine uptake by cationic drugs/compounds indicated a minor contribution of transport systems that accept cationic drugs (e.g., verapamil), as well as solute carrier (SLC) organic cation transporters. Collectively, these outcomes suggest that carrier-mediated transport systems, which differ from reported transporters and mechanisms, play a crucial role in the retinal distribution of amantadine across the inner/outer BRB.
Collapse
|
14
|
Byrne EM, Llorián-Salvador M, Tang M, Margariti A, Chen M, Xu H. IL-17A Damages the Blood-Retinal Barrier through Activating the Janus Kinase 1 Pathway. Biomedicines 2021; 9:831. [PMID: 34356895 PMCID: PMC8301352 DOI: 10.3390/biomedicines9070831] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/06/2021] [Accepted: 07/14/2021] [Indexed: 12/16/2022] Open
Abstract
Blood-retinal barrier (BRB) dysfunction underlies macular oedema in many sight-threatening conditions, including diabetic macular oedema, neovascular age-related macular degeneration and uveoretinitis. Inflammation plays an important role in BRB dysfunction. This study aimed to understand the role of the inflammatory cytokine IL-17A in BRB dysfunction and the mechanism involved. Human retinal pigment epithelial (RPE) cell line ARPE19 and murine brain endothelial line bEnd.3 were cultured on transwell membranes to model the outer BRB and inner BRB, respectively. IL-17A treatment (3 days in bEnd.3 cells and 6 days in ARPE19 cells) disrupted the distribution of claudin-5 in bEnd.3 cells and ZO-1 in ARPE19 cells, reduced the transepithelial/transendothelial electrical resistance (TEER) and increased permeability to FITC-tracers in vitro. Intravitreal (20 ng/1 μL/eye) or intravenous (20 ng/g) injection of recombinant IL-17A induced retinal albumin leakage within 48 h in C57BL/6J mice. Mechanistically, IL-17A induced Janus kinase 1 (JAK1) phosphorylation in bEnd.3 but not ARPE19 cells. Blocking JAK1 with Tofacitinib prevented IL-17A-mediated claudin-5 dysmorphia in bEnd.3 cells and reduced albumin leakage in IL-17A-treated mice. Our results suggest that IL-17A can damage the BRB through the activating the JAK1 signaling pathway, and targeting this pathway may be a novel approach to treat inflammation-induced macular oedema.
Collapse
Affiliation(s)
| | | | | | | | | | - Heping Xu
- The Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen’s University Belfast, Belfast BT9 7BL, UK; (E.M.B.); (M.L.-S.); (M.T.); (A.M.); (M.C.)
| |
Collapse
|
15
|
Yuan C, Mo Y, Yang J, Zhang M, Xie X. Influences of advanced glycosylation end products on the inner blood-retinal barrier in a co-culture cell model in vitro. Open Life Sci 2020; 15:619-628. [PMID: 33817250 PMCID: PMC7747502 DOI: 10.1515/biol-2020-0067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/25/2020] [Accepted: 07/06/2020] [Indexed: 11/24/2022] Open
Abstract
Advanced glycosylation end products (AGEs) are harmful factors that can damage the inner blood–retinal barrier (iBRB). Rat retinal microvascular endothelial cells (RMECs) were isolated and cultured, and identified by anti-CD31 and von Willebrand factor polyclonal antibodies. Similarly, rat retinal Müller glial cells (RMGCs) were identified by H&E staining and with antibodies of glial fibrillary acidic protein and glutamine synthetase. The transepithelial electrical resistance (TEER) value was measured with a Millicell electrical resistance system to observe the leakage of the barrier. Transwell cell plates for co-culturing RMECs with RMGCs were used to construct an iBRB model, which was then tested with the addition of AGEs at final concentrations of 50 and 100 mg/L for 24, 48, and 72 h. AGEs in the in vitro iBRB model constructed by RMEC and RMGC co-culture led to the imbalance of the vascular endothelial growth factor (VEGF) and pigment epithelial derivative factor (PEDF), and the permeability of the RMEC layer increased because the TEER decreased in a dose- and time-dependent manner. AGEs increased VEGF but lowered PEDF in a dose- and time-dependent manner. The intervention with AGEs led to the change of the transendothelial resistance of the RMEC layer likely caused by the increased ratio of VEGF/PEDF.
Collapse
Affiliation(s)
- Chen Yuan
- Eye School, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province, People's Republic of China
| | - Ya Mo
- Department of Ophthalmology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, Sichuan Province, People's Republic of China
| | - Jie Yang
- Department of Neurology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, Sichuan Province, People's Republic of China
| | - Mei Zhang
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine & Key Laboratory of Standardization of Chinese Herbal Medicines of Ministry of Education & State Key Laboratory Breeding Base of Systematic Research, Development and Utilization of Chinese Medicine Resources, Chengdu, Sichuan Province, People's Republic of China
| | - Xuejun Xie
- Department of Ophthalmology, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, 610072, Sichuan Province, People's Republic of China
| |
Collapse
|
16
|
Davies AE, Williams RL, Lugano G, Pop SR, Kearns VR. In vitro and computational modelling of drug delivery across the outer blood-retinal barrier. Interface Focus 2020; 10:20190132. [PMID: 32194934 PMCID: PMC7061949 DOI: 10.1098/rsfs.2019.0132] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2020] [Indexed: 12/22/2022] Open
Abstract
The ability to produce rapid, cost-effective and human-relevant data has the potential to accelerate the development of new drug delivery systems. Intraocular drug delivery is an area undergoing rapid expansion, due to the increase in sight-threatening diseases linked to increasing age and lifestyle factors. The outer blood-retinal barrier (OBRB) is important in this area of drug delivery, as it separates the eye from the systemic blood flow. This study reports the development of complementary in vitro and in silico models to study drug transport from silicone oil across the OBRB. Monolayer cultures of a human retinal pigmented epithelium cell line, ARPE-19, were added to chambers and exposed to a controlled flow to simulate drug clearance across the OBRB. Movement of dextran molecules and release of ibuprofen from silicone oil in this model were measured. Corresponding simulations were developed using COMSOL Multiphysics computational fluid dynamics software and validated using independent in vitro datasets. Computational simulations were able to predict dextran movement and ibuprofen release, with all of the features of the experimental release profiles being observed in the simulated data. Simulated values for peak concentrations of permeated dextran and ibuprofen released from silicone oil were within 18% of the in vitro results. This model could be used as a predictive tool for drug transport across this important tissue.
Collapse
Affiliation(s)
- Alys E. Davies
- Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
| | - Rachel L. Williams
- Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
| | - Gaia Lugano
- Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
| | - Serban R. Pop
- Department of Computer Science, University of Chester, Chester, UK
| | - Victoria R. Kearns
- Department of Eye and Vision Science, University of Liverpool, Liverpool, UK
| |
Collapse
|
17
|
Fresta CG, Fidilio A, Caruso G, Caraci F, Giblin FJ, Marco Leggio G, Salomone S, Drago F, Bucolo C. A New Human Blood-Retinal Barrier Model Based on Endothelial Cells, Pericytes, and Astrocytes. Int J Mol Sci 2020; 21:E1636. [PMID: 32121029 PMCID: PMC7084779 DOI: 10.3390/ijms21051636] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/21/2020] [Accepted: 02/25/2020] [Indexed: 12/16/2022] Open
Abstract
Blood-retinal barrier (BRB) dysfunction represents one of the most significant changes occurring during diabetic retinopathy. We set up a high-reproducible human-based in vitro BRB model using retinal pericytes, retinal astrocytes, and retinal endothelial cells in order to replicate the human in vivo environment with the same numerical ratio and layer order. Our findings showed that high glucose exposure elicited BRB breakdown, enhanced permeability, and reduced the levels of junction proteins such as ZO-1 and VE-cadherin. Furthermore, an increased expression of pro-inflammatory mediators (IL-1β, IL-6) and oxidative stress-related enzymes (iNOS, Nox2) along with an increased production of reactive oxygen species were observed in our triple co-culture paradigm. Finally, we found an activation of immune response-regulating signaling pathways (Nrf2 and HO-1). In conclusion, the present model mimics the closest human in vivo milieu, providing a valuable tool to study the impact of high glucose in the retina and to develop novel molecules with potential effect on diabetic retinopathy.
Collapse
Affiliation(s)
- Claudia G. Fresta
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95125 Catania, Italy; (C.G.F.); (G.M.L.); (S.S.)
| | - Annamaria Fidilio
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.F.); (F.C.)
| | | | - Filippo Caraci
- Department of Drug Sciences, University of Catania, 95125 Catania, Italy; (A.F.); (F.C.)
- Oasi Research Institute—IRCCS, 94018 Troina, Italy;
| | - Frank J. Giblin
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA;
| | - Gian Marco Leggio
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95125 Catania, Italy; (C.G.F.); (G.M.L.); (S.S.)
- Center for Research in Ocular Pharmacology-CERFO, University of Catania, 95125 Catania, Italy
| | - Salvatore Salomone
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95125 Catania, Italy; (C.G.F.); (G.M.L.); (S.S.)
- Center for Research in Ocular Pharmacology-CERFO, University of Catania, 95125 Catania, Italy
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95125 Catania, Italy; (C.G.F.); (G.M.L.); (S.S.)
- Center for Research in Ocular Pharmacology-CERFO, University of Catania, 95125 Catania, Italy
| | - Claudio Bucolo
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, 95125 Catania, Italy; (C.G.F.); (G.M.L.); (S.S.)
- Eye Research Institute, Oakland University, Rochester, MI 48309, USA;
- Center for Research in Ocular Pharmacology-CERFO, University of Catania, 95125 Catania, Italy
| |
Collapse
|
18
|
Ragelle H, Goncalves A, Kustermann S, Antonetti DA, Jayagopal A. Organ-On-A-Chip Technologies for Advanced Blood-Retinal Barrier Models. J Ocul Pharmacol Ther 2019; 36:30-41. [PMID: 31140899 PMCID: PMC6985766 DOI: 10.1089/jop.2019.0017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 04/02/2019] [Indexed: 12/16/2022] Open
Abstract
The blood-retinal barrier (BRB) protects the retina by maintaining an adequate microenvironment for neuronal function. Alterations of the junctional complex of the BRB and consequent BRB breakdown in disease contribute to a loss of neuronal signaling and vision loss. As new therapeutics are being developed to prevent or restore barrier function, it is critical to implement physiologically relevant in vitro models that recapitulate the important features of barrier biology to improve disease modeling, target validation, and toxicity assessment. New directions in organ-on-a-chip technology are enabling more sophisticated 3-dimensional models with flow, multicellularity, and control over microenvironmental properties. By capturing additional biological complexity, organs-on-chip can help approach actual tissue organization and function and offer additional tools to model and study disease compared with traditional 2-dimensional cell culture. This review describes the current state of barrier biology and barrier function in ocular diseases, describes recent advances in organ-on-a-chip design for modeling the BRB, and discusses the potential of such models for ophthalmic drug discovery and development.
Collapse
Affiliation(s)
- Héloïse Ragelle
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - Andreia Goncalves
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Harbor, Michigan
| | - Stefan Kustermann
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| | - David A. Antonetti
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan, Ann Harbor, Michigan
| | - Ashwath Jayagopal
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., Basel, Switzerland
| |
Collapse
|
19
|
Lee S, Kang IK, Kim JH, Jung BK, Park K, Chang H, Lee JY, Lee H. Relationship Between Neutralizing Antibodies Against Adeno-Associated Virus in the Vitreous and Serum: Effects on Retinal Gene Therapy. Transl Vis Sci Technol 2019; 8:14. [PMID: 31016068 PMCID: PMC6467092 DOI: 10.1167/tvst.8.2.14] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 12/26/2018] [Indexed: 11/24/2022] Open
Abstract
Purpose We determine the prevalence of neutralizing antibodies (NAbs) to adeno-associated virus (AAV) in the vitreous humor and serum of patients with vitreoretinal diseases and investigate the relationship between NAb titers in the vitreous humor and serum. Methods We analyzed NAbs to AAV serotypes 2, 5, 8, and 9 via in vitro neutralization in the vitreous humor and serum from 32 patients requiring vitrectomy for vitreoretinal diseases. The blood-retinal barrier (BRB) was evaluated for integrity based on preoperative examinations, with vitreous hemorrhage (VH) on funduscopy or dye leakage on fluorescein angiography observed indicating disruption. Results NAb levels were much lower in the vitreous humor than in the serum regardless of serotype. Patients with VH had higher levels of NAbs in the vitreous humor than those without VH. The NAb ratio (ratio between NAb titers in the serum and vitreous humor) was much lower in patients with epiretinal membrane with than in those without leakage. A significantly lower NAb ratio was noticed in patients with than in those without BRB disruptions. Conclusions The NAb ratio between levels in serum and vitreous humor varies according to the condition of the BRB. Therefore, in addition to measuring the serum NAb level, physicians should examine BRB integrity when planning retinal gene therapy. Translational Relevance This study provides substantial basis for retinal gene therapy using AAVs and how maintenance of BRB integrity in target diseases should be considered.
Collapse
Affiliation(s)
- Suhwan Lee
- Department of Ophthalmology, Kangwon National University Hospital, Kangwon National University Graduate School of Medicine, Chuncheon, Korea
| | - Im Kyeung Kang
- Department of Microbiology, University of Ulsan College of Medicine, Seoul, Korea.,Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Ji Hyun Kim
- Department of Microbiology, University of Ulsan College of Medicine, Seoul, Korea.,Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| | - Bok Kyoung Jung
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Keerang Park
- Biopharmaceutical R&D Center, Chungbuk Health & Science University, Cheongju-si, Chungbuk, Korea
| | | | - Joo Yong Lee
- Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea.,Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Heuiran Lee
- Department of Microbiology, University of Ulsan College of Medicine, Seoul, Korea.,Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Korea
| |
Collapse
|
20
|
Huang Y, He J, Liang H, Hu K, Jiang S, Yang L, Mei S, Zhu X, Yu J, Kijlstra A, Yang P, Hou S. Aryl Hydrocarbon Receptor Regulates Apoptosis and Inflammation in a Murine Model of Experimental Autoimmune Uveitis. Front Immunol 2018; 9:1713. [PMID: 30090104 PMCID: PMC6068235 DOI: 10.3389/fimmu.2018.01713] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/12/2018] [Indexed: 12/14/2022] Open
Abstract
Uveitis is characterized as a common cause of blindness worldwide. Aryl hydrocarbon receptor (AhR), a ligand-activated nuclear receptor, has been implicated to play a role in human uveitis, although the exact mechanisms remain poorly understood. The purpose of this study was to enhance our knowledge concerning the role of AhR during intraocular inflammation. We immunized wild-type and AhR-knockout C57BL/6J mice with IRBP651–670 to induce experimental autoimmune uveitis (EAU). Disease severity was evaluated with both clinical and histopathological grading. Blood–retinal barrier (BRB) integrity was tested by Evans blue and tight junction proteins qualifications. Apoptosis was measured using TdT-mediated dUTP nick end labeling staining. Macrophage/microglia activation and polarization were studied by immunofluorescence and Western blot. Following EAU induction, AhR−/− mice had more severe clinical and histopathological manifestations of uveitis than AhR+/+ mice. Increased vascular permeability and apoptotic cells were observed in AhR−/− EAU mice when compared with AhR+/+ EAU mice. In addition, AhR−/− EAU mice showed evidence of a significantly increased macrophage/microglia cells and a stronger polarization from the M2 to the M1 phenotype as compared to AhR+/+ EAU mice. The levels of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β were increased in AhR−/− EAU mice, which was associated with the activation of NF-κB and signal transducers and activators of transcription (STAT) pathways. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an agonist of AhR, caused a significant decrease in the clinical and histopathological manifestations, preserved BRB integrity, reduced apoptotic cells, inhibited macrophage/microglia activation, and shifted their polarization from M1 toward M2. Moreover, decreased expression of pro-inflammatory cytokines including TNF-α, IL-6, and IL-1β and inhibition of NF-κB and STAT pathways were found in EAU mice following TCDD treatment. In conclusion, AhR activation with TCDD exhibits an immunomodulatory effect by reducing BRB breakdown, inhibiting retinal cell apoptosis, and reducing pro-inflammatory cytokine expression during EAU. The underlying mechanism may involve the modulation of macrophages/microglia polarization and the downregulation of NF-κB and STAT pathways.
Collapse
Affiliation(s)
- Yike Huang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Junchi He
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Huaping Liang
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Ke Hu
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Shaoqiu Jiang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Lu Yang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Suyin Mei
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Xiao Zhu
- Guangdong Provincial Key Laboratory of Medical Molecular Diagnostics, Dongguan Scientific Research Center, Guangdong Medical University, Dongguan, China
| | - Jing Yu
- State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Aize Kijlstra
- University Eye Clinic Maastricht, Maastricht, Netherlands
| | - Peizeng Yang
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| | - Shengping Hou
- The First Affiliated Hospital of Chongqing Medical University, Chongqing Eye Institute, Chongqing Key Laboratory of Ophthalmology, Chongqing, China
| |
Collapse
|
21
|
Santiago AR, Boia R, Aires ID, Ambrósio AF, Fernandes R. Sweet Stress: Coping With Vascular Dysfunction in Diabetic Retinopathy. Front Physiol 2018; 9:820. [PMID: 30057551 PMCID: PMC6053590 DOI: 10.3389/fphys.2018.00820] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/12/2018] [Indexed: 12/15/2022] Open
Abstract
Oxidative stress plays key roles in the pathogenesis of retinal diseases, such as diabetic retinopathy. Reactive oxygen species (ROS) are increased in the retina in diabetes and the antioxidant defense system is also compromised. Increased ROS stimulate the release of pro-inflammatory cytokines, promoting a chronic low-grade inflammation involving various signaling pathways. An excessive production of ROS can lead to retinal endothelial cell injury, increased microvascular permeability, and recruitment of inflammatory cells at the site of inflammation. Recent studies have started unraveling the complex crosstalk between retinal endothelial cells and neuroglial cells or leukocytes, via both cell-to-cell contact and secretion of cytokines. This crosstalk is essential for the maintenance of the integrity of retinal vascular structure. Under diabetic conditions, an aberrant interaction between endothelial cells and other resident cells of the retina or invading inflammatory cells takes place in the retina. Impairment in the secretion and flow of molecular signals between different cells can compromise the retinal vascular architecture and trigger angiogenesis. In this review, the synergistic contributions of redox-inflammatory processes for endothelial dysfunction in diabetic retinopathy will be examined, with particular attention paid to endothelial cell communication with other retinal cells.
Collapse
Affiliation(s)
- Ana R Santiago
- Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI, University of Coimbra, Coimbra, Portugal.,Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - Raquel Boia
- Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - Inês D Aires
- Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - António F Ambrósio
- Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - Rosa Fernandes
- Coimbra Institute for Clinical and Biomedical Research, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI, University of Coimbra, Coimbra, Portugal
| |
Collapse
|
22
|
Ramos CJ, Lin C, Liu X, Antonetti DA. The EPAC-Rap1 pathway prevents and reverses cytokine-induced retinal vascular permeability. J Biol Chem 2017; 293:717-730. [PMID: 29158262 DOI: 10.1074/jbc.m117.815381] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 11/15/2017] [Indexed: 12/31/2022] Open
Abstract
Increased retinal vascular permeability contributes to macular edema, a leading cause of vision loss in eye pathologies such as diabetic retinopathy, age-related macular degeneration, and central retinal vein occlusions. Pathological changes in vascular permeability are driven by growth factors such as VEGF and pro-inflammatory cytokines such as TNF-α. Identifying the pro-barrier mechanisms that block vascular permeability and restore the blood-retinal barrier (BRB) may lead to new therapies. The cAMP-dependent guanine nucleotide exchange factor (EPAC) exchange-protein directly activated by cAMP promotes exchange of GTP in the small GTPase Rap1. Rap1 enhances barrier properties in human umbilical endothelial cells by promoting adherens junction assembly. We hypothesized that the EPAC-Rap1 signaling pathway may regulate the tight junction complex of the BRB and may restore barrier properties after cytokine-induced permeability. Here, we show that stimulating EPAC or Rap1 activation can prevent or reverse VEGF- or TNF-α-induced permeability in cell culture and in vivo Moreover, EPAC activation inhibited VEGF receptor (VEGFR) signaling through the Ras/MEK/ERK pathway. We also found that Rap1B knockdown or an EPAC antagonist increases endothelial permeability and that VEGF has no additive effect, suggesting a common pathway. Furthermore, GTP-bound Rap1 promoted tight junction assembly, and loss of Rap1B led to loss of junctional border organization. Collectively, our results indicate that the EPAC-Rap1 pathway helps maintain basal barrier properties in the retinal vascular endothelium and activation of the EPAC-Rap1 pathway may therefore represent a potential therapeutic strategy to restore the BRB.
Collapse
Affiliation(s)
- Carla J Ramos
- From the Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan 48105
| | - Chengmao Lin
- From the Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan 48105
| | - Xuwen Liu
- From the Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan 48105
| | - David A Antonetti
- From the Department of Ophthalmology and Visual Sciences, University of Michigan, Kellogg Eye Center, Ann Arbor, Michigan 48105
| |
Collapse
|
23
|
Baumann B, Sterling J, Song Y, Song D, Fruttiger M, Gillies M, Shen W, Dunaief JL. Conditional Müller Cell Ablation Leads to Retinal Iron Accumulation. Invest Ophthalmol Vis Sci 2017; 58:4223-4234. [PMID: 28846772 PMCID: PMC5574447 DOI: 10.1167/iovs.17-21743] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 07/07/2017] [Indexed: 12/25/2022] Open
Abstract
Purpose Retinal iron accumulation is observed in a wide range of retinal degenerative diseases, including AMD. Previous work suggests that Müller glial cells may be important mediators of retinal iron transport, distribution, and regulation. A transgenic model of Müller cell loss recently demonstrated that primary Müller cell ablation leads to blood-retinal barrier leakage and photoreceptor degeneration, and it recapitulates clinical features observed in macular telangiectasia type 2 (MacTel2), a rare human disease that features Müller cell loss. We used this mouse model to determine the effect of Müller cell loss on retinal iron homeostasis. Methods Changes in total retinal iron levels after Müller cell ablation were measured using inductively coupled plasma mass spectrometry. Corresponding changes in the expression of iron flux and iron storage proteins were determined using quantitative PCR, Western analysis, and immunohistochemistry. Results Müller cell loss led to blood-retinal barrier breakdown and increased iron levels throughout the neurosensory retina. There were corresponding changes in mRNA and/or protein levels of ferritin, transferrin receptor, ferroportin, Zip8, and Zip14. There were also increased iron levels within the RPE of retinal sections from a patient with MacTel2 and both RPE and neurosensory retina of a patient with diabetic retinopathy, which, like MacTel2, causes retinal vascular leakage. Conclusion This study shows that Müller cells and the blood-retinal barrier play pivotal roles in the regulation of retinal iron homeostasis. The retinal iron accumulation resulting from blood-retinal barrier dysfunction may contribute to retinal degeneration in this model and in diseases such as MacTel2 and diabetic retinopathy.
Collapse
Affiliation(s)
- Bailey Baumann
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Jacob Sterling
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Ying Song
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Delu Song
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Marcus Fruttiger
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Mark Gillies
- Save Sight Institute, The University of Sydney, Sydney, Australia
| | - Weiyong Shen
- Save Sight Institute, The University of Sydney, Sydney, Australia
| | - Joshua L. Dunaief
- F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, United States
| |
Collapse
|
24
|
van der Wijk AE, Hughes JM, Klaassen I, Van Noorden CJF, Schlingemann RO. Is leukostasis a crucial step or epiphenomenon in the pathogenesis of diabetic retinopathy? J Leukoc Biol 2017; 102:993-1001. [PMID: 28724696 DOI: 10.1189/jlb.3ru0417-139] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 06/26/2017] [Indexed: 11/24/2022] Open
Abstract
Leukostasis in the retinal microvasculature in animal model studies of diabetes is associated with the development of diabetes-like retinopathy. Therefore, it is generally assumed that adhesion of leukocytes is a central event inciting a chronic, low-grade form of inflammation that causes the vascular abnormalities that are specific for the early stages of diabetic retinopathy (DR), which culminate in diabetic macular edema, proliferative DR, and vision loss in humans. Here, we review the literature critically with respect to leukostasis and assess its pathologic consequences in the human diabetic retina. First, we review the pathologic processes that are known to be involved in the development of human DR. Then, we summarize experimental evidence for the role of leukostasis in the development of DR and the mechanisms involved in leukostasis in the retina. Based on our critical review, we conclude that leukostasis may be an epiphenomenon of the diabetic retinal milieu, rather than a crucial, specific step in the development of human DR.
Collapse
Affiliation(s)
- Anne-Eva van der Wijk
- Department of Ophthalmology, Ocular Angiogenesis Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| | - John M Hughes
- Department of Ophthalmology, Ocular Angiogenesis Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| | - Ingeborg Klaassen
- Department of Ophthalmology, Ocular Angiogenesis Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| | - Cornelis J F Van Noorden
- Department of Ophthalmology, Ocular Angiogenesis Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and.,Cellular Imaging Core Facility, Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Reinier O Schlingemann
- Department of Ophthalmology, Ocular Angiogenesis Group, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; .,Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; and
| |
Collapse
|
25
|
Affiliation(s)
- Arup Das
- Department of Surgery, Division of Ophthalmology, University of New Mexico School of Medicine, Albuquerque, New Mexico, United States
| |
Collapse
|
26
|
Van Hove I, Lefevere E, De Groef L, Sergeys J, Salinas-Navarro M, Libert C, Vandenbroucke R, Moons L. MMP-3 Deficiency Alleviates Endotoxin-Induced Acute Inflammation in the Posterior Eye Segment. Int J Mol Sci 2016; 17:ijms17111825. [PMID: 27809288 PMCID: PMC5133826 DOI: 10.3390/ijms17111825] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 10/20/2016] [Accepted: 10/25/2016] [Indexed: 01/04/2023] Open
Abstract
Matrix metalloproteinase-3 (MMP-3) is known to mediate neuroinflammatory processes by activating microglia, disrupting blood-central nervous system barriers and supporting neutrophil influx into the brain. In addition, the posterior part of the eye, more specifically the retina, the retinal pigment epithelium (RPE) and the blood-retinal barrier, is affected upon neuroinflammation, but a role for MMP-3 during ocular inflammation remains elusive. We investigated whether MMP-3 contributes to acute inflammation in the eye using the endotoxin-induced uveitis (EIU) model. Systemic administration of lipopolysaccharide induced an increase in MMP-3 mRNA and protein expression level in the posterior part of the eye. MMP-3 deficiency or knockdown suppressed retinal leukocyte adhesion and leukocyte infiltration into the vitreous cavity in mice subjected to EIU. Moreover, retinal and RPE mRNA levels of intercellular adhesion molecule 1 (Icam1), interleukin 6 (Il6), cytokine-inducible nitrogen oxide synthase (Nos2) and tumor necrosis factor α (Tnfα), which are key molecules involved in EIU, were clearly reduced in MMP-3 deficient mice. In addition, loss of MMP-3 repressed the upregulation of the chemokines monocyte chemoattractant protein (MCP)-1 and (C-X-C motif) ligand 1 (CXCL1). These findings suggest a contribution of MMP-3 during EIU, and its potential use as a therapeutic drug target in reducing ocular inflammation.
Collapse
Affiliation(s)
- Inge Van Hove
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
- Laboratory of Experimental Ophthalmology, Department of Neurosciences, KU Leuven, B-3000 Leuven, Belgium.
| | - Evy Lefevere
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
- Laboratory of Experimental Ophthalmology, Department of Neurosciences, KU Leuven, B-3000 Leuven, Belgium.
| | - Lies De Groef
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
- Laboratory of Experimental Ophthalmology, Department of Neurosciences, KU Leuven, B-3000 Leuven, Belgium.
| | - Jurgen Sergeys
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
- Laboratory of Experimental Ophthalmology, Department of Neurosciences, KU Leuven, B-3000 Leuven, Belgium.
| | - Manuel Salinas-Navarro
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
| | - Claude Libert
- Inflammation Research Center, VIB, B-9052 Ghent, Belgium.
- Department of Biomedical Molecular Biology, Ghent University, B-9052 Ghent, Belgium.
| | - Roosmarijn Vandenbroucke
- Inflammation Research Center, VIB, B-9052 Ghent, Belgium.
- Department of Biomedical Molecular Biology, Ghent University, B-9052 Ghent, Belgium.
| | - Lieve Moons
- Neural Circuit Development and Regeneration Research Group, Department of Biology, Katholieke Universiteit Leuven (KU Leuven), B-3000 Leuven, Belgium.
| |
Collapse
|
27
|
Canning P, Kenny BA, Prise V, Glenn J, Sarker MH, Hudson N, Brandt M, Lopez FJ, Gale D, Luthert PJ, Adamson P, Turowski P, Stitt AW. Lipoprotein-associated phospholipase A2 (Lp-PLA2) as a therapeutic target to prevent retinal vasopermeability during diabetes. Proc Natl Acad Sci U S A 2016; 113:7213-8. [PMID: 27298369 DOI: 10.1073/pnas.1514213113] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Lipoprotein-associated phospholipase A2 (Lp-PLA2) hydrolyses oxidized low-density lipoproteins into proinflammatory products, which can have detrimental effects on vascular function. As a specific inhibitor of Lp-PLA2, darapladib has been shown to be protective against atherogenesis and vascular leakage in diabetic and hypercholesterolemic animal models. This study has investigated whether Lp-PLA2 and its major enzymatic product, lysophosphatidylcholine (LPC), are involved in blood-retinal barrier (BRB) damage during diabetic retinopathy. We assessed BRB protection in diabetic rats through use of species-specific analogs of darapladib. Systemic Lp-PLA2 inhibition using SB-435495 at 10 mg/kg (i.p.) effectively suppressed BRB breakdown in streptozotocin-diabetic Brown Norway rats. This inhibitory effect was comparable to intravitreal VEGF neutralization, and the protection against BRB dysfunction was additive when both targets were inhibited simultaneously. Mechanistic studies in primary brain and retinal microvascular endothelial cells, as well as occluded rat pial microvessels, showed that luminal but not abluminal LPC potently induced permeability, and that this required signaling by the VEGF receptor 2 (VEGFR2). Taken together, this study demonstrates that Lp-PLA2 inhibition can effectively prevent diabetes-mediated BRB dysfunction and that LPC impacts on the retinal vascular endothelium to induce vasopermeability via VEGFR2. Thus, Lp-PLA2 may be a useful therapeutic target for patients with diabetic macular edema (DME), perhaps in combination with currently administered anti-VEGF agents.
Collapse
|
28
|
Nakaizumi A, Fukumoto M, Kida T, Suzuki H, Morishita S, Satou T, Oku H, Ikeda T, Nakamura K. Measurement of serum and vitreous concentrations of anti-type II collagen antibody in diabetic retinopathy. Clin Ophthalmol 2015; 9:543-7. [PMID: 25848204 PMCID: PMC4376299 DOI: 10.2147/opth.s75422] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Background Autoimmune mechanisms have been postulated as a cause of diabetic retinopathy (DR), as several autoantibodies have reportedly been detected in the serum of DR patients. In this present study, we measured serum and vitreous levels of anti-type II collagen (anti-II-C) antibodies in DR patients and investigated their association with the mechanism of development of DR. Patients and methods Blood samples were obtained from patients with proliferative DR and from patients with diabetic macular edema who underwent vitrectomy at Osaka Medical College, Takatsuki City, Osaka, Japan. Diabetic patients without DR were also included. The control group consisted of age- and sex-matched patients with noninflammatory eye diseases who underwent eye surgery for retinal detachment or for cataracts. The levels of anti-II-C immunoglobulin (Ig)G antibody in the vitreous and serum were measured using a human/monkey anti-II-C IgG assay kit. Results The serum levels of anti-II-C IgG antibody were significantly higher in the DR patients than in the patients with noninflammatory eye disease (56.8±33.8 units/mL versus 30.5±13.7 units/mL, respectively; P<0.05, Fisher’s exact test). These levels were also significantly higher in the diabetic patients without DR than in the patients with noninflammatory eye disease (76.3±49.7 units/mL versus 30.5±13.7 units/mL, respectively; P<0.01, Fisher’s exact test). However, anti-II-C IgG antibody levels were unable to be detected in all of the obtained vitreous fluid samples. Conclusion The development and progression of DR may be related to a mechanism involving intraocular type II collagen, which normally has immunological tolerance as a sequestered antigen. In DR, the disruption of the blood–retinal barrier leads to contact between the intraocular type II collagen and immunocompetent cells, and to subsequent activation of the autoimmune mechanism.
Collapse
Affiliation(s)
- Atsuko Nakaizumi
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Masanori Fukumoto
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Teruyo Kida
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Hiroyuki Suzuki
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Seita Morishita
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Takaki Satou
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Hidehiro Oku
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | - Tsunehiko Ikeda
- Department of Ophthalmology, Osaka Medical College, Takatsuki City, Osaka, Japan
| | | |
Collapse
|
29
|
Kim J, Kim CS, Lee YM, Sohn E, Jo K, Kim JS. Vaccinium myrtillus extract prevents or delays the onset of diabetes--induced blood-retinal barrier breakdown. Int J Food Sci Nutr 2015; 66:236-42. [PMID: 25582181 DOI: 10.3109/09637486.2014.979319] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Many dietary supplements have been sold through advertising their large number of beneficial effects. The aim of this study was to determine whether bilberries (Vaccinium myrtillus) help to prevent diabetes-induced retinal vascular dysfunction in vivo. V. myrtillus extract (VME; 100 mg/kg) was orally administered to streptozotocin-induced diabetic rats for 6 weeks. All diabetic rats exhibited hyperglycemia, and VME did not affect the blood glucose levels and body weight during the experiments. In the fluorescein-dextran angiography, the fluorescein leakage was significantly reduced in diabetic rats treated with VME. VME treatment also decreased markers of diabetic retinopathy, such as retinal vascular endothelial growth factor (VEGF) expression and degradation of zonula occludens-1, occludin and claudin-5 in diabetic rats. In conclusion, VME may prevent or delay the onset of early diabetic retinopathy. These findings have important implications for prevention of diabetic retinopathy using a dietary bilberry supplement.
Collapse
Affiliation(s)
- Junghyun Kim
- Korean Medicine Based Herbal Drug Development Group, Herbal Medicine Research Division, Korea Institute of Oriental Medicine , Daejeon , South Korea
| | | | | | | | | | | |
Collapse
|
30
|
Li X, Gu X, Boyce TM, Zheng M, Reagan AM, Qi H, Mandal N, Cohen AW, Callegan MC, Carr DJJ, Elliott MH. Caveolin-1 increases proinflammatory chemoattractants and blood-retinal barrier breakdown but decreases leukocyte recruitment in inflammation. Invest Ophthalmol Vis Sci 2014; 55:6224-34. [PMID: 25159208 DOI: 10.1167/iovs.14-14613] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
PURPOSE Caveolin-1 (Cav-1), the signature protein of caveolae, modulates inflammatory responses, and innate immunity. However, Cav-1's role in retinal inflammation has not been rigorously tested. In this study, we examined the effect of Cav-1 ablation on the sensitivity of the retina to inflammation. METHODS Cav-1 knockout (KO) mice were challenged by intravitreal injection of lipopolysaccharide (LPS) and inflammatory cell recruitment was assessed by flow cytometry and immunohistochemistry. Leukostasis was assessed in retinal flatmounts after perfusion with FITC-labeled Concanavalin A (FITC-ConA). Chemoattractants were measured by multiplex immunoassays. Blood-retinal barrier (BRB) breakdown was assessed quantitatively by a FITC-dextran permeability assay. The ratio of extravascular to total immune cells was determined by CD45 immunohistochemistry of retinal flatmounts. RESULTS Inflammatory challenge resulted in significant blunting of proinflammatory cytokine (monocyte chemoattractant protein-1 [MCP-1/CCL2], CXCL1/KC, IL-6, and IL-1β) responses as well as reduced inflammatory BRB breakdown in Cav-1 KO retinas. Paradoxically, Cav-1 deficiency resulted in significantly increased recruitment of immune cells compared with controls as well as increased leukostasis. A similar ratio of extravascular/total leukocytes were found in Cav-1 KO and wild-type (WT) retinas suggesting that Cav-1 deficient leukocytes were as competent to extravasate as those from WT mice. We found increased levels of circulating immune cells in naïve (not challenged with LPS) Cav-1 KO mice compared with controls. CONCLUSIONS Caveolin-1 paradoxically modulates inflammatory signaling and leukocyte infiltration through distinct mechanisms. We hypothesize that Cav-1 expression may enhance inflammatory signaling while at the same time supporting the physical properties of the BRB.
Collapse
Affiliation(s)
- Xiaoman Li
- 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
| | - Timothy M Boyce
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Min Zheng
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Alaina M Reagan
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Hui Qi
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Nawajes Mandal
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Alex W Cohen
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Michelle C Callegan
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Daniel J J Carr
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States Department of Microbiology & Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Michael H Elliott
- Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| |
Collapse
|
31
|
Fujii S, Setoguchi C, Kawazu K, Hosoya KI. Impact of P-glycoprotein on blood-retinal barrier permeability: comparison of blood-aqueous humor and blood-brain barrier using mdr1a knockout rats. Invest Ophthalmol Vis Sci 2014; 55:4650-8. [PMID: 24985475 DOI: 10.1167/iovs.13-13819] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The purpose of this study was to clarify the impact of P-glycoprotein (P-gp) on blood-retinal barrier (BRB) and blood-aqueous humor barrier (BAB) permeability, in contrast to blood-brain barrier (BBB) permeability. METHODS Permeabilities of six compounds, including P-gp substrates (quinidine, digoxin, and verapamil), were investigated in wild-type and mdr1a knockout rats using retinal, aqueous humor, and brain uptake index (RUI, AHUI, and BUI, respectively) methods and integration plot analysis. RESULTS In both rat strains, quinidine, digoxin, and verapamil were transported by P-gp across each barrier; however, the impact of P-gp on retinal uptake of quinidine and verapamil was less pronounced than that on brain uptake. The apparent influx permeability clearance (Kin) values of verapamil in retina obtained from wild-type and knockout rats were similar (0.824 ± 0.201 and 0.849 ± 0.980 mL/min·g retina, respectively; mean ± SD; n = 3 rats). The Kin in aqueous humor and brain obtained from knockout rats was, respectively, 3-fold and 12-fold higher than that of wild-type (P < 0.05). In P-gp-deficient conditions, the RUI and AHUI of quinidine, digoxin, and verapamil, as well as the BUI of quinidine and digoxin, were decreased by P-gp inhibitors. However, the BUI of verapamil was not changed by P-gp inhibitors. Results suggest that carrier-mediated influx transporters exist in the blood-ocular barriers and that the function of verapamil influx transporters is markedly different between the retina and brain. CONCLUSIONS In both rat strains, P-gp operates in the blood-ocular barriers, and the impact of P-gp on BRB permeability to quinidine and verapamil is lower than that on BBB permeability.
Collapse
Affiliation(s)
- Shinobu Fujii
- Nara Research and Development Center, Santen Pharmaceutical Co., Ltd., Nara, Japan Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Chikako Setoguchi
- Nara Research and Development Center, Santen Pharmaceutical Co., Ltd., Nara, Japan
| | - Kouichi Kawazu
- Nara Research and Development Center, Santen Pharmaceutical Co., Ltd., Nara, Japan
| | - Ken-ichi Hosoya
- Department of Pharmaceutics, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| |
Collapse
|
32
|
Fan Y, Liu K, Wang Q, Ruan Y, Ye W, Zhang Y. Exendin-4 alleviates retinal vascular leakage by protecting the blood-retinal barrier and reducing retinal vascular permeability in diabetic Goto-Kakizaki rats. Exp Eye Res 2014; 127:104-16. [PMID: 24910901 DOI: 10.1016/j.exer.2014.05.004] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 05/08/2014] [Accepted: 05/11/2014] [Indexed: 12/11/2022]
Abstract
The breakdown of the inner endothelial blood-retinal barrier (BRB) and subsequent retinal vascular leakage are the main causes of vision loss due to diabetic retinopathy (DR). Exendin-4 (E4) is a long-acting agonist of the glucagon-like peptide 1 hormone receptor (GLP-1R) that is widely used in clinics and has shown a neuroprotective effect. Our previous studies demonstrated the protective effect of E4 in early experimental DR; however, the molecular and cellular mechanisms that mediate this protective effect are not fully known. The BRB plays a key role in DR. We speculated that E4 may exert its protective effects on the BRB. To test this hypothesis, E4 (0.1 μg/2 μL/eye) or vehicle were intravitreally injected into diabetic Goto-Kakizaki(GK) rats and control animals. The results revealed that E4 significantly inhibited the reductions in electroretinogram (ERG) amplitudes in the GK rats, particularly in the b-wave and oscillatory potentials (OPs). E4 upregulated retinal GLP-1R expression and downregulated the expressions of placental growth factor (PLGF) and vascular endothelial growth factor (VEGF) via the ERK and AKT/PKB pathways. Decreases in tight junction protein (i.e., claudin-5 and occludin) expression and increases in Evans blue permeation (EBP) were inhibited by E4. Similar results were also found in primary rat Müller cells in high glucose concentration cultures in vitro. We conclude that E4 may protect the BRB from diabetic insults by decreasing PLGF and ICAM-1 expression and maintaining the integrity of the BRB. Thus, E4 treatment may be an effective therapeutic approach for DR.
Collapse
Affiliation(s)
- Yichao Fan
- Department of Ophthalmology, Huashan Hospital Affiliated to Fudan University, 12 Middle Wulumuqi Road, Shanghai, China
| | - Kun Liu
- Department of Ophthalmology, First People's Hospital of Shanghai Affiliated with Shanghai Jiaotong University, Shanghai, China
| | - Qingping Wang
- Department of Ophthalmology, Huashan Hospital Affiliated to Fudan University, 12 Middle Wulumuqi Road, Shanghai, China
| | - Yuanyuan Ruan
- Key Laboratory of Glycoconjugate Research, Ministry of Public Health, Shanghai Medical College of Fudan University, Shanghai, China; Department of Biochemistry and Molecular Biology, Shanghai Medical College of Fudan University, Shanghai, China
| | - Wen Ye
- Department of Ophthalmology, Huashan Hospital Affiliated to Fudan University, 12 Middle Wulumuqi Road, Shanghai, China.
| | - Yu Zhang
- Department of Ophthalmology, Huashan Hospital Affiliated to Fudan University, 12 Middle Wulumuqi Road, Shanghai, China.
| |
Collapse
|
33
|
Hussein KA, Choksi K, Akeel S, Ahmad S, Megyerdi S, El-Sherbiny M, Nawaz M, Abu El-Asrar A, Al-Shabrawey M. Bone morphogenetic protein 2: a potential new player in the pathogenesis of diabetic retinopathy. Exp Eye Res 2014; 125:79-88. [PMID: 24910902 DOI: 10.1016/j.exer.2014.05.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 03/10/2014] [Accepted: 05/15/2014] [Indexed: 12/23/2022]
Abstract
Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus. Vision loss in DR principally occurs due to breakdown of the blood-retinal barrier (BRB), leading to macular edema, retinal detachment and inner retinal and vitreous hemorrhage. Several growth factors have been shown to play crucial role in the development of these vascular changes; however, the cellular and molecular mechanisms of DR are not yet fully revealed. In the current study we investigated the role of bone morphogenetic protein-2 (BMP2) in DR. We examined the changes in the protein levels of BMP2 in human vitreous and retina in addition to the mouse retina of streptozotocin-induced diabetes. To detect the source of BMP2 during diabetes, human retinal endothelial cells (hRECs) were subjected to high glucose (HG) for 5 days and levels of BMP2 protein were analyzed in conditioned media of these cells relative to control. We also evaluated the effect of BMP2 on the levels of VEGF in cultured rat Müller cells (rMC1). In addition, we tested the pro-inflammatory effects of BMP2 by examining its effect on leukocyte adhesion to cultured hRECs, and levels of adhesion molecules and cytokines production. Finally, the effect of different concentrations of BMP2 on permeability of confluent monolayer of hRECs was evaluated using FITC-Dextran flux permeability assay and by measuring Transcellular Electrical Resistance (TER) using Electric Cell-substrate Impedance Sensing (ECIS). Our results show, for the first time, the up-regulation of BMP2 in diabetic human and mouse retinas in addition to its detection in vitreous of patients with proliferative DR (72 ± 7 pg/ml). In vitro, hRECs showed upregulation of BMP2 in HG conditions suggesting that these cells are a potential source of BMP2 in diabetic conditions. Furthermore, BMP2 induced VEGF secretion by Müller cells in-vitro; and showed a dose response in increasing permeability of cultured hRECs. Meanwhile, BMP2 pro-inflammatory effects were recognized by its ability to induce leukocyte adhesion to the hRECs, intercellular adhesion molecule-1 (ICAM-1) and upregulation of interleukin-6 and 8 (IL-6 and IL-8). These results show that BMP2 could be a contributing growth factor to the development of microvascular dysfunction during DR via enhancing both pro-angiogenic and inflammatory pathways. Our findings suggest BMP2 as a potential therapeutic target to prevent/treat DR.
Collapse
Affiliation(s)
- Khaled A Hussein
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Oral and Dental Research Division, Department of Surgery and Medicine, National Research Center, Egypt
| | - Karishma Choksi
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA
| | - Sara Akeel
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA
| | - Saif Ahmad
- Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Biological Sciences, Rabigh College of Science and Arts, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Sylvia Megyerdi
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA
| | - Mohamed El-Sherbiny
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Anatomy, Mansoura Faculty of Medicine, Mansoura, Egypt
| | - Mohamed Nawaz
- Department of Ophthalmology, King Saud University, Riyadh, Saudi Arabia
| | | | - Mohamed Al-Shabrawey
- Department of Oral Biology/Anatomy College of Dental Medicine, Georgia Reagents University (Augusta) (GRU(A)), USA; Vision Discovery Institute, Medical College of Georgia, GRU(A), USA; Department of Anatomy, Mansoura Faculty of Medicine, Mansoura, Egypt; Department of Ophthalmology, Medical College of Georgia, GRU(A), USA; Department of Cellular Biology and Anatomy, GRU(A), USA.
| |
Collapse
|
34
|
Abstract
The principal function of an epithelium is to form a dynamic barrier that regulates movement between body compartments. Each epithelium is specialized with barrier functions that are specific for the tissues it serves. The apical surface commonly faces a lumen, but the retinal pigment epithelium (RPE) appears to be unique by a facing solid tissue, the sensory retina. Nonetheless, there exists a thin (subretinal) space that can become fluid filled during pathology. RPE separates the subretinal space from the blood supply of the outer retina, thereby forming the outer blood-retinal barrier. The intricate interaction between the RPE and sensory retina presents challenges for learning how accurately culture models reflect native behavior. The challenge is heightened by findings that detail the variation of RPE barrier proteins both among species and at different stages of the life cycle. Among the striking differences is the expression of claudin family members. Claudins are the tight junction proteins that regulate ion diffusion across the spaces that lie between the cells of a monolayer. Claudin expression by RPE varies with species and life-stage, which implies functional differences among commonly used animal models. Investigators have turned to transcriptomics to supplement functional studies when comparing native and cultured tissue. The most detailed studies of the outer blood-retinal barrier have focused on human RPE with transcriptome and functional studies reported for human fetal, adult, and stem-cell derived RPE.
Collapse
Affiliation(s)
- Lawrence J Rizzolo
- Departments of Surgery and of Ophthalmology and Visual Science, Yale University School of Medicine, PO Box 208062, 310 Cedar Street, New Haven, CT 06520-8062, USA.
| |
Collapse
|
35
|
Muthusamy A, Lin CM, Shanmugam S, Lindner HM, Abcouwer SF, Antonetti DA. Ischemia-reperfusion injury induces occludin phosphorylation/ubiquitination and retinal vascular permeability in a VEGFR-2-dependent manner. J Cereb Blood Flow Metab 2014; 34:522-31. [PMID: 24398936 PMCID: PMC3948134 DOI: 10.1038/jcbfm.2013.230] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 11/05/2013] [Accepted: 11/25/2013] [Indexed: 02/02/2023]
Abstract
Retinal ischemia-reperfusion (IR) induces neurodegenaration as well as blood-retinal barrier (BRB) breakdown causing vascular permeability. Whereas the neuronal death has been extensively studied, the molecular mechanisms related to BRB breakdown in IR injury remain poorly understood. In this study, we investigated the early changes in tight junctional (TJ) proteins in response to IR injury. Ischemia-reperfusion injury was induced in male rat retinas by increasing the intraocular pressure for 45 minutes followed by natural reperfusion. The results demonstrate that IR injury induced occludin Ser490 phosphorylation and ubiquitination within 15 minutes of reperfusion with subsequent vascular permeability. Immunohistochemical analysis revealed a rapid increase in occludin Ser490 phosphorylation and loss of Zonula occludens-1 (ZO-1) protein, particularly in arterioles. Ischemia-reperfusion injury also rapidly induced the activation and phosphorylation of vascular endothelial growth factor receptor-2 (VEGFR-2) at tyrosine 1175. Blocking vascular endothelial growth factor (VEGF) function by intravitreal injection of bevacizumab prevented VEGFR-2 activation, occludin phosphorylation, and vascular permeability. These studies suggest a novel mechanism of occludin Ser490 phosphorylation and ubiquitination downstream of VEGFR2 activation associated with early IR-induced vascular permeability.
Collapse
Affiliation(s)
- Arivalagan Muthusamy
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Cheng-Mao Lin
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Sumathi Shanmugam
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Heather M Lindner
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - Steven F Abcouwer
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| | - David A Antonetti
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, Ann Arbor, Michigan, USA
| |
Collapse
|
36
|
Shen J, Durairaj C, Lin T, Liu Y, Burke J. Ocular pharmacokinetics of intravitreally administered brimonidine and dexamethasone in animal models with and without blood-retinal barrier breakdown. Invest Ophthalmol Vis Sci 2014; 55:1056-66. [PMID: 24448267 DOI: 10.1167/iovs.13-13650] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We compared ocular and systemic pharmacokinetics of brimonidine and dexamethasone following a single intravitreal dose in animals with blood-retinal barrier (BRB) breakdown and in healthy controls. METHODS We induced BRB breakdown in rabbits by intravitreal injection of recombinant human VEGF165 and choroidal neovascularization (CNV) in monkeys with laser. Control and disease animals then received single intravitreal injections of brimonidine alone, dexamethasone alone, or brimonidine in combination with dexamethasone. Ocular tissues and plasma were collected and quantified for drug concentration using LC-MS/MS assays. Statistical analysis was performed to compare the pharmacokinetic parameters between the control and disease animal models. RESULTS In rabbits, brimonidine and dexamethasone exposure, as assessed by area under the drug concentration-time curve (AUC) in aqueous humor, retina, and choroid, was lower in disease than control animals, with a greater difference observed for dexamethasone than brimonidine. In monkeys, dexamethasone exposure was lower in disease than control animals for the central retina/choroid and peripheral choroid, whereas brimonidine exposure was lower in disease animals only in the central retina/choroid. Plasma exposure to both drugs was comparable between control and disease animals in both species. CONCLUSIONS In animal models with a breakdown of the blood-retina barrier, drug clearance could be increased, resulting in lower drug concentration in ocular tissues compared to normal animals. However, the extent of difference may be compound- and disease model-specific. Therefore, extrapolation of ocular pharmacokinetic data obtained in normal animals to disease models for the purpose of pharmacokinetic/pharmacodynamic data analysis should be performed with caution.
Collapse
Affiliation(s)
- Jie Shen
- Department of Pharmacokinetics and Drug Disposition, Allergan, Inc., Irvine, California
| | | | | | | | | |
Collapse
|
37
|
Abstract
Macular edema that results from blood–retinal barrier (BRB) breakdown is a cause of significant visual loss associated with a variety of ocular disorders. BRB breakdown is a complex process that is regulated by multiple factors and involves different mechanisms. A variety of therapeutic approaches have shown modest suppression of macular edema, but to obtain greater efficacy, it is likely that multiple molecules, operating through distinct mechanisms, may need to be targeted. Studies aimed at identifying key target molecules and the optimal strategies for inhibiting them are ongoing in several laboratories.
Collapse
|
38
|
Vinores SA, Wang Y, Vinores MA, Derevjanik NL, Shi A, Klein DA, Detrick B, Hooks JJ. Blood-retinal barrier breakdown in experimental coronavirus retinopathy: association with viral antigen, inflammation, and VEGF in sensitive and resistant strains. J Neuroimmunol 2001; 119:175-82. [PMID: 11585619 PMCID: PMC7119735 DOI: 10.1016/s0165-5728(01)00374-5] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Intraocular coronavirus inoculation results in a biphasic retinal disease in susceptible mice (BALB/c) characterized by an acute inflammatory response, followed by retinal degeneration associated with autoimmune reactivity. Resistant mice (CD-1), when similarly inoculated, only develop the early phase of the disease. Blood-retinal barrier (BRB) breakdown occurs in the early phase in both strains, coincident with the onset of inflammation. As the inflammation subsides, the extent of retinal vascular leakage is decreased, indicating that BRB breakdown in experimental coronavirus retinopathy (ECOR) is primarily due to inflammation rather than to retinal cell destruction. Vascular endothelial growth factor (VEGF) is upregulated only in susceptible mice during the secondary (retinal degeneration) phase.
Collapse
Affiliation(s)
- S A Vinores
- 825 Maumenee Building, Wilmer Ophthalmologic Institute, Johns Hopkins University School of Medicine, 600 N. Wolfe Street, Baltimore, MD 21287-9289, USA.
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Penfold PL, Wen L, Madigan MC, Gillies MC, King NJ, Provis JM. Triamcinolone acetonide modulates permeability and intercellular adhesion molecule-1 (ICAM-1) expression of the ECV304 cell line: implications for macular degeneration. Clin Exp Immunol 2000; 121:458-65. [PMID: 10971511 PMCID: PMC1905725 DOI: 10.1046/j.1365-2249.2000.01316.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Whilst animal studies and a pilot clinical trial suggest that intravitreal triamcinolone acetonide (TA) may be useful in the treatment of age-related macular degeneration (AMD), its mode of action remains to be fully elucidated. The present study has investigated the capacity of TA to modulate the expression of adhesion molecules and permeability using a human epithelial cell line (ECV304) as a model of the outer blood-retinal barrier (BRB). The influence of TA on the expression of ICAM-1 and MHC-I was studied on resting and phorbol myristate acetate (PMA)- or interferon-gamma (IFN-gamma)- and/or tumour necrosis factor-alpha (TNF-alpha)-activated cells using flow cytometry and immunocytochemistry. Additionally, ECV304 cells were grown to confluence in uncoated Transwell chambers; transepithelial resistance (TER) across resting and PMA-activated cells was monitored. TA significantly decreased the paracellular permeability of ECV304 cells and down-regulated ICAM-1 expression, consistent with immunocytochemical observations. PMA-induced permeability changes were dose-dependent and TA decreased permeability of both resting and PMA-activated monolayers. MHC-I expression by ECV304 cells however, was not significantly affected by TA treatment. The modulation of TER and ICAM-1 expression in vitro correlate with clinical observations, suggesting re-establishment of the BRB and down-regulation of inflammatory markers are the principal effects of intravitreal TA in vivo. The results further indicate that TA has the potential to influence cellular permeability, including the barrier function of the retinal pigment epithelium (RPE) in AMD-affected retinae.
Collapse
Affiliation(s)
- P L Penfold
- Department of Clinical Ophthalmology, University of Sydney, Sydney, Australia.
| | | | | | | | | | | |
Collapse
|