1
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Ignatova I, Frolov R, Nymark S. The retinal pigment epithelium displays electrical excitability and lateral signal spreading. BMC Biol 2023; 21:84. [PMID: 37069561 PMCID: PMC10111697 DOI: 10.1186/s12915-023-01559-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 03/10/2023] [Indexed: 04/19/2023] Open
Abstract
BACKGROUND The non-neuronal retinal pigment epithelium (RPE) functions in intimate association with retinal photoreceptors, performing a multitude of tasks critical for maintaining retinal homeostasis and collaborating with retinal glial cells to provide metabolic support and ionic buffering. Accordingly, the RPE has recently been shown to display dynamic properties mediated by an array of ion channels usually more characteristic of astrocytes and excitable cells. The recent discovery of canonical voltage-activated Na+ channels in the RPE and their importance for phagocytosis of photoreceptor outer segments raises a question about their electrogenic function. Here, we performed a detailed electrophysiological analysis related to the functioning of these channels in human embryonic stem cell (hESC)-derived RPE. RESULTS Our studies examining the electrical properties of the hESC-RPE revealed that its membrane mainly displays passive properties in a broad voltage range, with the exception of depolarization-induced spikes caused by voltage-activated Na+ current (INa). Spike amplitude depended on the availability of INa and spike kinetics on the membrane time constant, and the spikes could be largely suppressed by TTX. Membrane resistance fluctuated rapidly and strongly, repeatedly changing over the course of recordings and causing closely correlated fluctuations in resting membrane potential. In a minority of cells, we found delayed secondary INa-like inward currents characterized by comparatively small amplitudes and slow kinetics, which produced secondary depolarizing spikes. Up to three consecutive delayed inward current waves were detected. These currents could be rapidly and reversibly augmented by applying L-type Ca2+ channel blocker nifedipine to diminish influx of calcium and thus increase gap junctional conductance. CONCLUSIONS This work shows, for the first time, that INa and INa-mediated voltage spikes can spread laterally through gap junctions in the monolayer of cells that are traditionally considered non-excitable. Our findings support a potential role of the RPE that goes beyond giving homeostatic support to the retina.
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Affiliation(s)
- Irina Ignatova
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | | | - Soile Nymark
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland.
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2
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Bhend ME, Kempuraj D, Sinha NR, Gupta S, Mohan RR. Role of aquaporins in corneal healing post chemical injury. Exp Eye Res 2023; 228:109390. [PMID: 36696947 PMCID: PMC9975064 DOI: 10.1016/j.exer.2023.109390] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/31/2022] [Accepted: 01/19/2023] [Indexed: 01/23/2023]
Abstract
Aquaporins (AQPs) are transmembrane water channel proteins that regulate the movement of water through the plasma membrane in various tissues including cornea. The cornea is avascular and has specialized microcirculatory mechanisms for homeostasis. AQPs regulate corneal hydration and transparency for normal vision. Currently, there are 13 known isoforms of AQPs that can be subclassified as orthodox AQPs, aquaglyceroporins (AQGPs), or supraquaporins (SAQPs)/unorthodox AQPs. AQPs are implicated in keratocyte function, inflammation, edema, angiogenesis, microvessel proliferation, and the wound-healing process in the cornea. AQPs play an important role in wound healing by facilitating the movement of corneal stromal keratocytes by squeezing through tight stromal matrix and narrow extracellular spaces to the wound site. Deficiency of AQPs can cause reduced concentration of hepatocyte growth factor (HGF) leading to reduced epithelial proliferation, reduced/impaired keratocyte migration, reduced number of keratocytes in the injury site, delayed and abnormal wound healing process. Dysregulated AQPs cause dysfunction in osmolar homeostasis as well as wound healing mechanisms. The cornea is a transparent avascular tissue that constitutes the anterior aspect of the outer covering of the eye and aids in two-thirds of visual light refraction. Being the outermost layer of the eye, the cornea is prone to injury. Of the 13 AQP isoforms, AQP1 is expressed in the stromal keratocytes and endothelial cells, and AQP3 and AQP5 are expressed in epithelial cells in the human cornea. AQPs can facilitate wound healing through aid in cellular migration, proliferation, migration, extracellular matrix (ECM) remodeling and autophagy mechanism. Corneal wound healing post-chemical injury requires an integrative and coordinated activity of the epithelium, stromal keratocytes, endothelium, ECM, and a battery of cytokines and growth factors to restore corneal transparency. If the chemical injury is mild, the cornea will heal with normal clarity, but severe injuries can lead to partial and/or permanent loss of corneal functions. Currently, the role of AQPs in corneal wound healing is poorly understood in the context of chemical injury. This review discusses the current literature and the role of AQPs in corneal homeostasis, wound repair, and potential therapeutic target for acute and chronic corneal injuries.
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Affiliation(s)
- Madeline E Bhend
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; School of Medicine, University of South Carolina, Columbia, SC, USA; Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Duraisamy Kempuraj
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Institute for Neuro-Immune Medicine, Dr. Kiran C. Patel College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA
| | - Nishant R Sinha
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
| | - Suneel Gupta
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA
| | - Rajiv R Mohan
- Department of Ophthalmology, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, USA; Mason Eye Institute, School of Medicine, University of Missouri, Columbia, MO, USA.
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3
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Cheng Y, Ren T, Wang N. Biomechanical homeostasis in ocular diseases: A mini-review. Front Public Health 2023; 11:1106728. [PMID: 36733902 PMCID: PMC9886686 DOI: 10.3389/fpubh.2023.1106728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 01/02/2023] [Indexed: 01/18/2023] Open
Abstract
Diabetes mellitus-induced hyperglycemia is responsible for multiple pathological ocular alternations from vasculopathy to biomechanical dyshomeostasis. Biomechanical homeostasis is crucial to maintain the normal physiological condition of the eyes. Biomechanical features vary in eye tissues regarding different anatomical positions, tissue components, and cellular functions. The disturbance in biomechanical homeostasis may result in different ocular diseases. In this review, we provide a preliminary sketch of the latest evidence on the mechano-environment of the eyeball and its possible influencing factors, thereby underscoring the relationship between the dyshomeostasis of ocular biomechanics and common eye diseases (e.g., diabetic retinopathy, keratoconus, glaucoma, spaceflight-associated neuro-ocular syndrome, retinal vein occlusion and myopia, etc.). Together with the reported evidence, we further discuss and postulate the potential role of biomechanical homeostasis in ophthalmic pathology. Some latest strategies to investigate the biomechanical properties in ocular diseases help unveil the pathological changes at multiple scales, offering references for making new diagnostic and treatment strategies targeting mechanobiology.
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Affiliation(s)
- Ying Cheng
- Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Tianmin Ren
- Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ningli Wang
- Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Eye Center, Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital Medical University, Beijing, China,Collaborative Innovation Center for Brain Disorders, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China,Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing, China,*Correspondence: Ningli Wang ✉
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4
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Maity A, Perotto S, Moschetta M, Hua H, Sardar S, Paternò GM, Tian J, Klein M, Adamo G, Lanzani G, Soci C. Resonant Enhancement of Polymer-Cell Optostimulation by a Plasmonic Metasurface. ACS OMEGA 2022; 7:42674-42680. [PMID: 36467911 PMCID: PMC9713778 DOI: 10.1021/acsomega.2c04812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 09/23/2022] [Indexed: 06/17/2023]
Abstract
Organic semiconductors have shown great potential as efficient bioelectronic materials. Specifically, photovoltaic polymers such as the workhorse poly(thiophene) derivatives, when stimulated with visible light, can depolarize neurons and generate action potentials, an effect that has been also employed for rescuing vision in blind rats. In this context, however, the coupling of such materials with optically resonant structures to enhance those photodriven biological effects is still in its infancy. Here, we employ the optical coupling between a nanostructured metasurface and poly(3-hexylthiophene) (P3HT) to improve the bioelectronic effects occurring upon photostimulation at the abiotic-biotic interface. In particular, we designed a spectrally tuned aluminum metasurface that can resonate with P3HT, hence augmenting the effective field experienced by the polymer. In turn, this leads to an 8-fold increase in invoked inward current in cells. This enhanced activation strategy could be useful to increase the effectiveness of P3HT-based prosthetic implants for degenerative retinal disorders.
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Affiliation(s)
- Arijit Maity
- Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
- Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
| | - Sara Perotto
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
| | - Matteo Moschetta
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
| | - Huang Hua
- Department
of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 28 Medical Drive, 117456 Singapore
| | - Samim Sardar
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
| | - Giuseppe Maria Paternò
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
- Department
of Physics, Politecnico di Milano and Center for Nano Science and
Technology, Istituto Italiano di Tecnologia, 20133 Milan, Italy
| | - Jingyi Tian
- Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
- Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
| | - Maciej Klein
- Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
- Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
| | - Giorgio Adamo
- Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
- Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
| | - Guglielmo Lanzani
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, via Pascoli 70/3, 20133 Milan, Italy
- Department
of Physics, Politecnico di Milano and Center for Nano Science and
Technology, Istituto Italiano di Tecnologia, 20133 Milan, Italy
| | - Cesare Soci
- Centre
for Disruptive Photonic Technologies, TPI, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
- Division
of Physics and Applied Physics, School of Physical and Mathematical
Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore
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5
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Beverley KM, Pattnaik BR. Inward rectifier potassium (Kir) channels in the retina: living our vision. Am J Physiol Cell Physiol 2022; 323:C772-C782. [PMID: 35912989 PMCID: PMC9448332 DOI: 10.1152/ajpcell.00112.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 07/25/2022] [Accepted: 07/25/2022] [Indexed: 11/22/2022]
Abstract
Channel proteins are vital for conducting ions throughout the body and are especially relevant to retina physiology. Inward rectifier potassium (Kir) channels are a class of K+ channels responsible for maintaining membrane potential and extracellular K+ concentrations. Studies of the KCNJ gene (that encodes Kir protein) expression identified the presence of all of the subclasses (Kir 1-7) of Kir channels in the retina or retinal-pigmented epithelium (RPE). However, functional studies have established the involvement of the Kir4.1 homotetramer and Kir4.1/5.1 heterotetramer in Müller glial cells, Kir2.1 in bipolar cells, and Kir7.1 in the RPE cell physiology. Here, we propose the potential roles of Kir channels in the retina based on the physiological contributions to the brain, pancreatic, and cardiac tissue functions. There are several open questions regarding the expressed KCNJ genes in the retina and RPE. For example, why does not the Kir channel subtype gene expression correspond with protein expression? Catching up with multiomics or functional "omics" approaches might shed light on posttranscriptional changes that might influence Kir subunit mRNA translation within the retina that guides our vision.
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Affiliation(s)
- Katie M Beverley
- Endocrinology and Reproductive Physiology Graduate Program, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- McPherson Eye Research Institute, University of Wisconsin, Madison, Wisconsin
| | - Bikash R Pattnaik
- Endocrinology and Reproductive Physiology Graduate Program, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
- McPherson Eye Research Institute, University of Wisconsin, Madison, Wisconsin
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin
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6
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Yang S, Wu Y, Wang C, Jin X. Ocular Surface Ion-Channels Are Closely Related to Dry Eye: Key Research Focus on Innovative Drugs for Dry Eye. Front Med (Lausanne) 2022; 9:830853. [PMID: 35308542 PMCID: PMC8927818 DOI: 10.3389/fmed.2022.830853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 02/07/2022] [Indexed: 11/13/2022] Open
Abstract
Abundant ion-channels, including various perceptual receptors, chloride channels, purinergic receptor channels, and water channels that exist on the ocular surface, play an important role in the pathogenesis of dry eye. Channel-targeting activators or inhibitor compounds, which have shown positive effects in in vivo and in vitro experiments, have become the focus of the dry eye drug research and development, and individual compounds have been applied in clinical experimental treatment. This review summarized various types of ion-channels on the ocular surface related to dry eye, their basic functions, and spatial distribution, and discussed basic and clinical research results of various channel receptor regulatory compounds. Therefore, further elucidating the relationship between ion-channels and dry eye will warrant research of dry eye targeted drug therapy.
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Affiliation(s)
- Shuo Yang
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yaying Wu
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - ChunYang Wang
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Xiuming Jin
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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7
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Wei C, Li Y, Feng X, Hu Z, Paquet-Durand F, Jiao K. RNA Biological Characteristics at the Peak of Cell Death in Different Hereditary Retinal Degeneration Mutants. Front Genet 2021; 12:728791. [PMID: 34777465 PMCID: PMC8586524 DOI: 10.3389/fgene.2021.728791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 09/21/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: The present work investigated changes in the gene expression, molecular mechanisms, and pathogenesis of inherited retinal degeneration (RD) in three different disease models, to identify predictive biomarkers for their varied phenotypes and to provide a better scientific basis for their diagnosis, treatment, and prevention. Methods: Differentially expressed genes (DEGs) between retinal tissue from RD mouse models obtained during the photoreceptor cell death peak period (Pde6b rd1 at post-natal (PN) day 13, Pde6b rd10 at PN23, Prph rd2 at PN29) and retinal tissue from C3H wild-type mice were identified using Illumina high-throughput RNA-sequencing. Co-expression gene modules were identified using a combination of GO and KEGG enrichment analyses and gene co-expression network analysis. CircRNA-miRNA-mRNA network interactions were studied by genome-wide circRNA screening. Results: Pde6b rd1 , Pde6b rd10 , and Prph rd2 mice had 1,926, 3,096, and 375 DEGs, respectively. Genes related to ion channels, stress, inflammatory processes, tumor necrosis factor (TNF) production, and microglial cell activation were up-regulated, while genes related to endoplasmic reticulum regulation, metabolism, and homeostasis were down-regulated. Differential expression of transcription factors and non-coding RNAs generally implicated in other human diseases was detected (e.g., glaucoma, diabetic retinopathy, and inherited retinal degeneration). CircRNA-miRNA-mRNA network analysis indicated that these factors may be involved in photoreceptor cell death. Moreover, excessive cGMP accumulation causes photoreceptor cell death, and cGMP-related genes were generally affected by different pathogenic gene mutations. Conclusion: We screened genes and pathways related to photoreceptor cell death. Additionally, up-stream regulatory factors, such as transcription factors and non-coding RNA and their interaction networks were analyzed. Furthermore, RNAs involved in RD were functionally annotated. Overall, this study lays a foundation for future studies on photoreceptor cell death mechanisms.
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Affiliation(s)
- Chunling Wei
- Kunming Medical University, Kunming, China.,Department of Ophthalmology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China
| | - Yan Li
- Department of Ophthalmology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China.,Key Laboratory of Yunnan Province, Yunnan Eye Institute, Kunming, China
| | - Xiaoxiao Feng
- Department of Ophthalmology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China.,Key Laboratory of Yunnan Province, Yunnan Eye Institute, Kunming, China
| | - Zhulin Hu
- Department of Ophthalmology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China.,Key Laboratory of Yunnan Province, Yunnan Eye Institute, Kunming, China
| | - François Paquet-Durand
- Institute for Ophthalmic Research, Eberhard-Karls-Universität Tübingen, Tübingen, Germany
| | - Kangwei Jiao
- Department of Ophthalmology, Affiliated Hospital of Yunnan University, Yunnan University, Kunming, China.,Key Laboratory of Yunnan Province, Yunnan Eye Institute, Kunming, China
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8
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Management of toxic optic neuropathy via a combination of Wharton's jelly-derived mesenchymal stem cells with electromagnetic stimulation. Stem Cell Res Ther 2021; 12:518. [PMID: 34579767 PMCID: PMC8477499 DOI: 10.1186/s13287-021-02577-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 08/27/2021] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To investigate the effect of the combination of Wharton's jelly derived mesenchymal stem cells (WJ-MSC) and high frequency repetitive electromagnetic stimulation (rEMS) in the therapy of toxic optic neuropathies with severe symptoms after the available current therapy modalities which were unsucessful. MATERIAL AND METHODS This prospective, open-label clinical phase-3 study was conducted at Ankara University Faculty of Medicine, Department of Ophthalmology between April 2019 and April 2021. Thirty-six eyes of 18 patients with toxic optic neuropathy (TON) were included in the study. Within 1-3 months after the emergency interventions, patients with various degrees of sequela visual disturbances were studied in this clinical trial. The cases were divided into three groups according to similar demographic characteristics. Group 1: Consists of 12 eyes of 12 patients treated with the WJ-MSC and rEMS combination in one eye. Group 2: Consists of 12 eyes of 12 patients treated with only rEMS in one eye. Group 3: Consists of 12 eyes of six patients treated with only WJ-MSC in both eyes. The course was evaluated by comparing the quantitive functional and structural assessment parameters measured before and at the fourth month of applications in each group. RESULTS The mean best corrected visual acuity (BCVA) delta change percentages of the groups can be ranked as: Group 1 (47%) > Group 3 (32%) > Group 2 (21%). The mean fundus perimetry deviation index (FPDI) delta change percentages of the groups can be ranked as: Group 1 (95%) > Group 2 (33%) > Group 3 (27%). The mean ganglion cell complex (GCC) thickness delta change (decrease in thickness) percentages can be ranked as: Group 1 (- 21%) > Group 3 (- 15%) > Group 2 (- 13%). The visual evoked potential (VEP) P100 latency delta change percentages of the groups can be ranked as: Group 1 (- 18%) > Group 3 (- 10%) > Group 2 (- 8%). The P100 amplitude delta change percentages of the groups can be ranked as: Group 1 (105%) > Group 3 (83%) > Group 2 (24%). CONCLUSION Toxic optic neuropathies are emergent pathologies that can result in acute and permanent blindness. After poisoning with toxic substances, progressive apoptosis continues in optic nerve axons and ganglion cells. After the proper first systemic intervention in intensive care clinic, the WJ-MSC and rEMS combination seems very effective in the short-term period in cases with TON. To prevent permanent blindness, a combination of WJ-MSC and rEMS application as soon as possible may increase the chance of success in currently untreatable cases. Trial Registration ClinicalTrials.gov ID: NCT04877067.
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9
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Ratnapriya R, Acar İE, Geerlings MJ, Branham K, Kwong A, Saksens NTM, Pauper M, Corominas J, Kwicklis M, Zipprer D, Starostik MR, Othman M, Yashar B, Abecasis GR, Chew EY, Ferrington DA, Hoyng CB, Swaroop A, den Hollander AI. Family-based exome sequencing identifies rare coding variants in age-related macular degeneration. Hum Mol Genet 2021; 29:2022-2034. [PMID: 32246154 PMCID: PMC7390936 DOI: 10.1093/hmg/ddaa057] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/18/2020] [Accepted: 03/26/2020] [Indexed: 12/24/2022] Open
Abstract
Genome-wide association studies (GWAS) have identified 52 independent variants at 34 genetic loci that are associated with age-related macular degeneration (AMD), the most common cause of incurable vision loss in the elderly worldwide. However, causal genes at the majority of these loci remain unknown. In this study, we performed whole exome sequencing of 264 individuals from 63 multiplex families with AMD and analyzed the data for rare protein-altering variants in candidate target genes at AMD-associated loci. Rare coding variants were identified in the CFH, PUS7, RXFP2, PHF12 and TACC2 genes in three or more families. In addition, we detected rare coding variants in the C9, SPEF2 and BCAR1 genes, which were previously suggested as likely causative genes at respective AMD susceptibility loci. Identification of rare variants in the CFH and C9 genes in our study validated previous reports of rare variants in complement pathway genes in AMD. We then extended our exome-wide analysis and identified rare protein-altering variants in 13 genes outside the AMD-GWAS loci in three or more families. Two of these genes, SCN10A and KIR2DL4, are of interest because variants in these genes also showed association with AMD in case-control cohorts, albeit not at the level of genome-wide significance. Our study presents the first large-scale, exome-wide analysis of rare variants in AMD. Further independent replications and molecular investigation of candidate target genes, reported here, would assist in gaining novel insights into mechanisms underlying AMD pathogenesis.
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Affiliation(s)
- Rinki Ratnapriya
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA.,Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - İlhan E Acar
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Maartje J Geerlings
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Kari Branham
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA
| | - Alan Kwong
- Center for Statistical Genetics, Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicole T M Saksens
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Marc Pauper
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Jordi Corominas
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Madeline Kwicklis
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA
| | - David Zipprer
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA
| | - Margaret R Starostik
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA
| | - Mohammad Othman
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA
| | - Beverly Yashar
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA
| | - Goncalo R Abecasis
- Center for Statistical Genetics, Department of Biostatistics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Emily Y Chew
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA
| | - Deborah A Ferrington
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Carel B Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
| | - Anand Swaroop
- Neurobiology, Neurodegeneration and Repair Laboratory (NNRL), National Eye Institute, Bethesda, MD 20892, USA
| | - Anneke I den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen 6500, The Netherlands
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10
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Rolando M, Barabino S. The Subtle Role of Para-inflammation in Modulating the Progression of Dry Eye Disease. Ocul Immunol Inflamm 2021; 29:811-816. [PMID: 34003707 DOI: 10.1080/09273948.2021.1906908] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In patients with DED, the continuous stimuli induced by excessive or persistent cold fiber sensors and overstimulation of nociceptors, as well as tear hyperosmolarity induced by evaporative stress, induce a transitory protective adaptation response called para-inflammation to restore ocular surface homeostasis. This mild subclinical inflammatory status (a type of hormetic response) can become chronic if the stimuli or tissue malfunction is present for a sustained period, causing persistent symptoms and damage to ocular surface epithelia.We review the mechanisms that characterize the transition from para-inflammation to a persistent inflammatory status of the ocular surface, including accumulation of biological waste and damaged/dysfunctional proteins, which, in normal conditions, are eliminated by autophagy, activation of the inflammasomes, and what is currently known about their role in DED pathogenesis. Furthermore, we analyze current treatments that can modulate the inflammatory response of the ocular surface and speculate about new possible therapies to treat para-inflammation.
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Affiliation(s)
| | - Stefano Barabino
- Ocular Surface and Dry Eye Center, ASST Fatebenefratelli-Sacco, Sacco Hospital - University of Milan, Milan, Italy
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11
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Mamaeva D, Jazouli Z, DiFrancesco ML, Erkilic N, Dubois G, Hilaire C, Meunier I, Boukhaddaoui H, Kalatzis V. Novel roles for voltage-gated T-type Ca 2+ and ClC-2 channels in phagocytosis and angiogenic factor balance identified in human iPSC-derived RPE. FASEB J 2021; 35:e21406. [PMID: 33724552 DOI: 10.1096/fj.202002754r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/13/2021] [Accepted: 01/19/2021] [Indexed: 01/26/2023]
Abstract
Human-induced pluripotent stem cell (hiPSC)-derived retinal pigment epithelium (RPE) is a powerful tool for pathophysiological studies and preclinical therapeutic screening, as well as a source for clinical cell transplantation. Thus, it must be validated for maturity and functionality to ensure correct data readouts and clinical safety. Previous studies have validated hiPSC-derived RPE as morphologically characteristic of the tissue in the human eye. However, information concerning the expression and functionality of ion channels is still limited. We screened hiPSC-derived RPE for the polarized expression of a panel of L-type (CaV 1.1, CaV 1.3) and T-type (CaV 3.1, CaV 3.3) Ca2+ channels, K+ channels (Maxi-K, Kir4.1, Kir7.1), and the Cl- channel ClC-2 known to be expressed in native RPE. We also tested the roles of these channels in key RPE functions using specific inhibitors. In addition to confirming the native expression profiles and function of certain channels, such as L-type Ca2+ channels, we show for the first time that T-type Ca2+ channels play a role in both phagocytosis and vascular endothelial growth factor (VEGF) secretion. Moreover, we demonstrate that Maxi-K and Kir7.1 channels are involved in the polarized secretion of VEGF and pigment epithelium-derived factor (PEDF). Furthermore, we show a novel localization for ClC-2 channel on the apical side of hiPSC-derived RPE, with an overexpression at the level of fluid-filled domes, and demonstrate that it plays an important role in phagocytosis, as well as VEGF and PEDF secretion. Taken together, hiPSC-derived RPE is a powerful model for advancing fundamental knowledge of RPE functions.
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Affiliation(s)
- Daria Mamaeva
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Zhour Jazouli
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Mattia L DiFrancesco
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Nejla Erkilic
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France.,National Reference Centre for Inherited Sensory Diseases, Montpellier University, CHU, Montpellier, France
| | - Gregor Dubois
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Cecile Hilaire
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France.,National Reference Centre for Inherited Sensory Diseases, Montpellier University, CHU, Montpellier, France
| | - Hassan Boukhaddaoui
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
| | - Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier, Inserm, Montpellier University, Montpellier, France
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12
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New Omics-Derived Perspectives on Retinal Dystrophies: Could Ion Channels-Encoding or Related Genes Act as Modifier of Pathological Phenotype? Int J Mol Sci 2020; 22:ijms22010070. [PMID: 33374679 PMCID: PMC7793472 DOI: 10.3390/ijms22010070] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 12/15/2020] [Accepted: 12/21/2020] [Indexed: 02/07/2023] Open
Abstract
Ion channels are membrane-spanning integral proteins expressed in multiple organs, including the eye. Here, ion channels play a role in several physiological processes, like signal transmission and visual processing. A wide range of mutations have been reported in the corresponding genes and their interacting subunit coding genes, which contribute significantly to a wide spectrum of ocular diseases collectively called channelopathies, a subgroup of inherited retinal dystrophies. Such mutations result in either a loss or gain-of channel functions affecting the structure, assembly, trafficking and localization of channel proteins. We investigated the probands of seven Italian and Egyptian families affected by not completely defined forms of inherited retinal dystrophies, by whole exome sequencing (WES) experiments, and found interesting variants in already known causative genes probably able to impair retinal functionalities. However, because such variants did not completely explain the phenotype manifested by each patient, we proceed to further investigate possible related genes carrying mutations that might complement previously found data, based on the common aspect linked to neurotransmission impairments. We found 10 mutated genes whose variants might alter important ligand binding sites differently distributed through all considered patients. Such genes encode for ion channels, or their regulatory proteins, and strictly interact with known causative genes, also sharing with them synaptic-related pathways. Taking into account several limitations that will be resolved by further experiments, we believe that our exploratory investigation will help scientists to provide a new promising paradigm for precise diagnosis of retinal dystrophies to facilitate the development of rational treatments.
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13
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Collin GB, Gogna N, Chang B, Damkham N, Pinkney J, Hyde LF, Stone L, Naggert JK, Nishina PM, Krebs MP. Mouse Models of Inherited Retinal Degeneration with Photoreceptor Cell Loss. Cells 2020; 9:cells9040931. [PMID: 32290105 PMCID: PMC7227028 DOI: 10.3390/cells9040931] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/05/2020] [Accepted: 04/07/2020] [Indexed: 12/12/2022] Open
Abstract
Inherited retinal degeneration (RD) leads to the impairment or loss of vision in millions of individuals worldwide, most frequently due to the loss of photoreceptor (PR) cells. Animal models, particularly the laboratory mouse, have been used to understand the pathogenic mechanisms that underlie PR cell loss and to explore therapies that may prevent, delay, or reverse RD. Here, we reviewed entries in the Mouse Genome Informatics and PubMed databases to compile a comprehensive list of monogenic mouse models in which PR cell loss is demonstrated. The progression of PR cell loss with postnatal age was documented in mutant alleles of genes grouped by biological function. As anticipated, a wide range in the onset and rate of cell loss was observed among the reported models. The analysis underscored relationships between RD genes and ciliary function, transcription-coupled DNA damage repair, and cellular chloride homeostasis. Comparing the mouse gene list to human RD genes identified in the RetNet database revealed that mouse models are available for 40% of the known human diseases, suggesting opportunities for future research. This work may provide insight into the molecular players and pathways through which PR degenerative disease occurs and may be useful for planning translational studies.
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Affiliation(s)
- Gayle B. Collin
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Navdeep Gogna
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Bo Chang
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Nattaya Damkham
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Jai Pinkney
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Lillian F. Hyde
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Lisa Stone
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Jürgen K. Naggert
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
| | - Patsy M. Nishina
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Correspondence: (P.M.N.); (M.P.K.); Tel.: +1-207-2886-383 (P.M.N.); +1-207-2886-000 (M.P.K.)
| | - Mark P. Krebs
- The Jackson Laboratory, Bar Harbor, Maine, ME 04609, USA; (G.B.C.); (N.G.); (B.C.); (N.D.); (J.P.); (L.F.H.); (L.S.); (J.K.N.)
- Correspondence: (P.M.N.); (M.P.K.); Tel.: +1-207-2886-383 (P.M.N.); +1-207-2886-000 (M.P.K.)
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14
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Molecular genetics of congenital cataracts. Exp Eye Res 2019; 191:107872. [PMID: 31770519 DOI: 10.1016/j.exer.2019.107872] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 12/18/2022]
Abstract
Congenital cataracts, the most common cause of visual impairment and blindness in children worldwide, have diverse etiologies. According to statistics analysis, about one quarter of congenital cataracts caused by genetic defects. Various mutations of more than one hundred genes have been identified in hereditary cataracts so far. In this review, we briefly summarize recent developments about the genetics, molecular mechanisms, and treatments of congenital cataracts. The studies of these pathogenic mutations and molecular genetics is making it possible for us to comprehend the underlying mechanisms of cataractogenesis and providing new insights into the preventive, diagnostic and therapeutic approaches of cataracts.
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Milićević N, Duursma A, Ten Asbroek ALMA, Felder-Schmittbuhl MP, Bergen AA. Does the circadian clock make RPE-mediated ion transport "tick" via SLC12A2 (NKCC1)? Chronobiol Int 2019; 36:1592-1598. [PMID: 31441327 DOI: 10.1080/07420528.2019.1653317] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The presence of a circadian clock in the retinal pigment epithelium (RPE) was discovered recently. However, little is known about mechanisms or processes regulated by the RPE clock. We cultured ARPE-19 monolayers in a transwell culture system, and we found rhythmic mRNA expression of the sodium-potassium-chloride co-transporter SLC12A2. We localized the corresponding protein product, NKCC1, on the apical membrane of ARPE-19 cells. We found that concentrations of sodium, potassium, and chloride oscillated in apical supernatants. The ion concentration gradients between supernatants strongly correlated with SLC12A2 mRNA expression. Our results suggest that the circadian clock regulates ion transport by the RPE via NKCC1 expression.
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Affiliation(s)
- Nemanja Milićević
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives , F-67000 Strasbourg , France.,Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9 , 1105 AZ, Amsterdam , the Netherlands
| | - Angelica Duursma
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9 , 1105 AZ, Amsterdam , the Netherlands
| | - Anneloor L M A Ten Asbroek
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9 , 1105 AZ, Amsterdam , the Netherlands
| | - Marie-Paule Felder-Schmittbuhl
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives , F-67000 Strasbourg , France
| | - Arthur A Bergen
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9 , 1105 AZ, Amsterdam , the Netherlands.,Department of Ophthalmology, Amsterdam UMC, University of Amsterdam, Meibergdreef 9 , 1105 AZ, Amsterdam , the Netherlands.,Department of Retinal Signal Processing, Netherlands Institute for Neuroscience (NIN-KNAW) , 1105 BA, Amsterdam , the Netherlands
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16
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Non-coding RNAome of RPE cells under oxidative stress suggests unknown regulative aspects of Retinitis pigmentosa etiopathogenesis. Sci Rep 2018; 8:16638. [PMID: 30413775 PMCID: PMC6226517 DOI: 10.1038/s41598-018-35086-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 10/29/2018] [Indexed: 12/26/2022] Open
Abstract
The discovery of thousands of non-coding RNAs has revolutionized molecular biology, being implicated in several biological processes and diseases. To clarify oxidative stress role on Retinitis pigmentosa, a very heterogeneous and inherited ocular disorder group characterized by progressive retinal degeneration, we realized a comparative transcriptome analysis of human retinal pigment epithelium cells, comparing two groups, one treated with oxLDL and one untreated, in four time points (1 h, 2 h, 4 h, 6 h). Data analysis foresaw a complex pipeline, starting from CLC Genomics Workbench, STAR and TopHat2/TopHat-Fusion alignment comparisons, followed by transcriptomes assembly and expression quantification. We then filtered out non-coding RNAs and continued the computational analysis roadmap with specific tools and databases for long non-coding RNAs (FEELnc), circular RNAs (CIRCexplorer, UROBORUS, CIRI, KNIFE, CircInteractome) and piwi-interacting RNAs (piRNABank, piRNA Cluster, piRBase, PILFER). Finally, all detected non-coding RNAs underwent pathway analysis by Cytoscape software. Eight-hundred and fifty-four non-coding RNAs, between long non-coding RNAs and PIWI-interacting, were differentially expressed throughout all considered time points, in treated and untreated samples. These non-coding RNAs target host genes involved in several biochemical pathways are related to compromised response to oxidative stress, visual functions, synaptic impairment of retinal neurotransmission, impairment of the interphotoreceptor matrix and blood – retina barrier, all leading to retinal cell death. These data suggest that non-coding RNAs could play a relevant role in Retinitis pigmentosa etiopathogenesis.
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17
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Hydrophobic alkyl chains substituted to the 8-position of cyclic nucleotides enhance activation of CNG and HCN channels by an intricate enthalpy - entropy compensation. Sci Rep 2018; 8:14960. [PMID: 30297855 PMCID: PMC6175941 DOI: 10.1038/s41598-018-33050-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 09/19/2018] [Indexed: 01/01/2023] Open
Abstract
Cyclic nucleotide-gated (CNG) and hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are tetrameric non-specific cation channels in the plasma membrane that are activated by either cAMP or cGMP binding to specific binding domains incorporated in each subunit. Typical apparent affinities of these channels for these cyclic nucleotides range from several hundred nanomolar to tens of micromolar. Here we synthesized and characterized novel cAMP and cGMP derivatives by substituting either hydrophobic alkyl chains or similar-sized more hydrophilic heteroalkyl chains to the 8-position of the purine ring with the aim to obtain full agonists of higher potency. The compounds were tested in homotetrameric CNGA2, heterotetrameric CNGA2:CNGA4:CNGB1b and homotetrameric HCN2 channels. We show that nearly all compounds are full agonists and that longer alkyl chains systematically increase the apparent affinity, at the best more than 30 times. The effects are stronger in CNG than HCN2 channels which, however, are constitutively more sensitive to cAMP. Kinetic analyses reveal that the off-rate is significantly slowed by the hydrophobic alkyl chains. Molecular dynamics simulations and free energy calculations suggest that an intricate enthalpy - entropy compensation underlies the higher apparent affinity of the derivatives with the longer alkyl chains, which is shown to result from a reduced loss of configurational entropy upon binding.
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18
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Pascual-Camps I, Barranco-Gonzalez H, Aviñó-Martínez J, Silva E, Harto-Castaño M. Diagnosis and Treatment Options for Achromatopsia: A Review of the Literature. J Pediatr Ophthalmol Strabismus 2018; 55:85-92. [PMID: 29257187 DOI: 10.3928/01913913-20171117-01] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 06/28/2017] [Indexed: 01/31/2023]
Abstract
Achromatopsia is a complex inherited retinal disease that affects the cone cell function. It is usually an autosomal-recessive disease and is characterized by pendular nystagmus, poor visual acuity, lack of color vision, and marked photophobia. CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6 gene mutations have been identified as associated with this disease. New diagnostic and therapeutic tools are being studied. Optical coherence tomography and fundus autofluorescence are important imaging techniques that provide significant information about the progression of the disease. The genetic approach for these patients is a current important issue and gene therapy is an ongoing therapeutic option already being studied in clinical trials. The purpose of this review was to survey the current knowledge on diagnosis and treatment options in achromatopsia. [J Pediatr Ophthalmol Strabismus. 2018;55(2):85-92.].
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Correction of Monogenic and Common Retinal Disorders with Gene Therapy. Genes (Basel) 2017; 8:genes8020053. [PMID: 28134823 PMCID: PMC5333042 DOI: 10.3390/genes8020053] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 01/19/2017] [Indexed: 11/16/2022] Open
Abstract
The past decade has seen major advances in gene-based therapies, many of which show promise for translation to human disease. At the forefront of research in this field is ocular disease, as the eye lends itself to gene-based interventions due to its accessibility, relatively immune-privileged status, and ability to be non-invasively monitored. A landmark study in 2001 demonstrating successful gene therapy in a large-animal model for Leber congenital amaurosis set the stage for translation of these strategies from the bench to the bedside. Multiple clinical trials have since initiated for various retinal diseases, and further improvements in gene therapy techniques have engendered optimism for alleviating inherited blinding disorders. This article provides an overview of gene-based strategies for retinal disease, current clinical trials that engage these strategies, and the latest techniques in genome engineering, which could serve as the next frontline of therapeutic interventions.
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