1
|
Chan ASY, Tun SBB, Lynn MN, Ho C, Tun TA, Girard MJA, Sultana R, Barathi VA, Aung T, Aihara M. Intravitreal Neuroglobin Mitigates Primate Experimental Glaucomatous Structural Damage in Association with Reduced Optic Nerve Microglial and Complement 3-Astrocyte Activation. Biomolecules 2023; 13:961. [PMID: 37371541 DOI: 10.3390/biom13060961] [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: 03/25/2023] [Revised: 05/18/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
Current management of glaucomatous optic neuropathy is limited to intraocular pressure control. Neuroglobin (Ngb) is an endogenous neuroprotectant expressed in neurons and astrocytes. We recently showed that exogenous intravitreal Ngb reduced inflammatory cytokines and microglial activation in a rodent model of hypoxia. We thus hypothesised that IVT-Ngb may also be neuroprotective in experimental glaucoma (EG) by mitigating optic nerve (ON) astrogliosis and microgliosis as well as structural damage. In this study using a microbead-induced model of EG in six Cynomolgus primates, optical coherence imaging showed that Ngb-treated EG eyes had significantly less thinning of the peripapillary minimum rim width, retinal nerve fibre layer thickness, and ON head cupping than untreated EG eyes. Immunohistochemistry confirmed that ON astrocytes overexpressed Ngb following Ngb treatment. A reduction in complement 3 and cleaved-caspase 3 activated microglia and astrocytes was also noted. Our findings in higher-order primates recapitulate the effects of neuroprotection by Ngb treatment in rodent EG studies and suggest that Ngb may be a potential candidate for glaucoma neuroprotection in humans.
Collapse
Affiliation(s)
- Anita S Y Chan
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Singapore National Eye Centre, Singapore 168751, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
| | - Sai B B Tun
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Myoe N Lynn
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Candice Ho
- Singapore Eye Research Institute, Singapore 169856, Singapore
| | - Tin A Tun
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore 169856, Singapore
| | | | - Veluchamy A Barathi
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Tin Aung
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Singapore National Eye Centre, Singapore 168751, Singapore
- Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Makoto Aihara
- Department of Ophthalmology, University of Tokyo, Tokyo 113-8654, Japan
| |
Collapse
|
2
|
Sun D, Wang B, Yang Z, Zhan Z, Li J, Lan Y. Protocol for laser-induced chronic ocular hypertension and intracameral injection in nonhuman primates. STAR Protoc 2022; 3:101801. [PMID: 36340883 PMCID: PMC9630776 DOI: 10.1016/j.xpro.2022.101801] [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] [Indexed: 11/06/2022] Open
Abstract
Laser-induced hypertension in nonhuman primates is used to mimic human glaucoma, the leading cause of irreversible blindness. In this protocol, we detail steps for laser-induced ocular hypertension in nonhuman primates by laser photocoagulation of the trabecular meshwork and subsequent intracameral injection. We further describe recording and evaluation of intraocular pressure changes and peripapillary retinal nerve fiber layer thickness. This protocol can assist researchers improve the success rate and repeatability of the procedure and reduce the number of nonhuman primates needed. For complete details on the use and execution of this protocol, please refer to Sun et al. (2022). Detailed description for general and ophthalmological examination before experiment Protocol to generate laser-induced chronic ocular hypertension in rhesus monkeys Laser photocoagulation of the trabecular meshwork followed by intracameral injection Approach is highly reproducible and offers a tool to test potential treatment strategies
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
Collapse
Affiliation(s)
- Difang Sun
- Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, School of Ophthalmology, Shandong First Medical University, Qingdao 266071, China,Department of Ophthalmology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China,Corresponding author
| | - Bin Wang
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao 266003, China
| | - Zhenlan Yang
- Department of Ophthalmology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China
| | - Zongyi Zhan
- Department of Ophthalmology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China,Corresponding author
| | - Jun Li
- Eye Institute of Shandong First Medical University, Qingdao Eye Hospital of Shandong First Medical University, State Key Laboratory Cultivation Base, Shandong Provincial Key Laboratory of Ophthalmology, School of Ophthalmology, Shandong First Medical University, Qingdao 266071, China,Corresponding author
| | - Yuqing Lan
- Department of Ophthalmology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou 510120, China,Corresponding author
| |
Collapse
|
3
|
Bikuna‐Izagirre M, Aldazabal J, Extramiana L, Moreno‐Montañés J, Carnero E, Paredes J. Technological advances in ocular trabecular meshwork in vitro models for glaucoma research. Biotechnol Bioeng 2022; 119:2698-2714. [PMID: 35836364 PMCID: PMC9543213 DOI: 10.1002/bit.28182] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 05/17/2022] [Accepted: 07/12/2022] [Indexed: 11/13/2022]
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide and is characterized by the progressive degeneration of the optic nerve. Intraocular pressure (IOP), which is considered to be the main risk factor for glaucoma development, builds up in response to the resistance (resistance to what?) provided by the trabecular meshwork (TM) to aqueous humor (AH) outflow. Although the TM and its relationship to AH outflow have remained at the forefront of scientific interest, researchers remain uncertain regarding which mechanisms drive the deterioration of the TM. Current tissue-engineering fabrication techniques have come up with promising approaches to successfully recreate the TM. Nonetheless, more accurate models are needed to understand the factors that make glaucoma arise. In this review, we provide a chronological evaluation of the technological milestones that have taken place in the field of glaucoma research, and we conduct a comprehensive comparison of available TM fabrication technologies. Additionally, we also discuss AH perfusion platforms, since they are essential for the validation of these scaffolds, as well as pressure-outflow relationship studies and the discovery of new IOP-reduction therapies.
Collapse
Affiliation(s)
- Maria Bikuna‐Izagirre
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
| | - Javier Aldazabal
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
| | - Leire Extramiana
- Departamento de oftalmología ClínicaClínica Universidad de NavarraPamplonaEspaña
| | | | - Elena Carnero
- Departamento de oftalmología ClínicaClínica Universidad de NavarraPamplonaEspaña
| | - Jacobo Paredes
- Tecnun School of EngineeringUniversity of NavarraSan SebastiánSpain
- Biomedical Engineering CenterUniversity of NavarraPamplonaSpain
| |
Collapse
|
4
|
Sainulabdeen A, Glidai Y, Wu M, Liu M, Alexopoulos P, Ishikawa H, Schuman JS, Wollstein G. 3D Microstructure of the Healthy Non-Human Primate Lamina Cribrosa by Optical Coherence Tomography Imaging. Transl Vis Sci Technol 2022; 11:15. [PMID: 35435922 PMCID: PMC9034718 DOI: 10.1167/tvst.11.4.15] [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] [Indexed: 02/05/2023] Open
Abstract
Purpose The lamina cribrosa (LC) has an important role in the pathophysiology of ocular diseases. The purpose of this study is to characterize in vivo, noninvasively, and in 3D the structure of the LC in healthy non-human primates (NHPs). Methods Spectral-domain optical coherence tomography (OCT; Leica, Chicago, IL) scans of the optic nerve head (ONH) were obtained from healthy adult rhesus macaques monkeys. Using a previously reported semi-automated segmentation algorithm, microstructure measurements were assessed in central and peripheral regions of an equal area, in quadrants and depth-wise. Linear mixed-effects models were used to compare parameters among regions, adjusting for visibility, age, analyzable depth, graded scan quality, disc area, and the correlation between eyes. Spearmen's rank correlation coefficients were calculated for assessing the association between the lamina's parameters. Results Sixteen eyes of 10 animals (7 males and 3 females; 9 OD, 7 OS) were analyzed with a mean age of 10.5 ± 2.1 years. The mean analyzable depth was 175 ± 37 µm, with average LC visibility of 25.4 ± 13.0% and average disc area of 2.67 ± 0.45mm2. Within this volume, an average of 74.9 ± 39.0 pores per eye were analyzed. The central region showed statistically significantly thicker beams than the periphery. The quadrant-based analysis showed significant differences between the superior and inferior quadrants. The anterior LC had smaller beams and pores than both middle and posterior lamina. Conclusions Our study provides in vivo microstructure details of NHP's LC to be used as the foundation for future studies. We demonstrated mostly small but statistically significant regional variations in LC microstructure that should be considered when comparing LC measurements.
Collapse
Affiliation(s)
| | - Yoav Glidai
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA
| | - Mengfei Wu
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA,Division of Biostatistics, Departments of Population Health and Environmental Medicine, NYU Langone Health, New York, NY, USA
| | - Mengling Liu
- Division of Biostatistics, Departments of Population Health and Environmental Medicine, NYU Langone Health, New York, NY, USA
| | | | - Hiroshi Ishikawa
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA,Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, USA
| | - Joel S. Schuman
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA,Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, USA,Center for Neural Science, NYU, New York, NY, USA
| | - Gadi Wollstein
- Department of Ophthalmology, NYU Langone Health, New York, NY, USA,Department of Biomedical Engineering, NYU Tandon School of Engineering, Brooklyn, NY, USA,Center for Neural Science, NYU, New York, NY, USA
| |
Collapse
|
5
|
Sun D, Zhan Z, Zeng R, Liu X, Wang B, Yang F, Huang S, Li Y, Yang Z, Su Y, Lan Y. Long-term and potent IOP-lowering effect of IκBα-siRNA in a nonhuman primate model of chronic ocular hypertension. iScience 2022; 25:104149. [PMID: 35445186 PMCID: PMC9014385 DOI: 10.1016/j.isci.2022.104149] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/28/2022] [Accepted: 03/20/2022] [Indexed: 11/26/2022] Open
Abstract
Glaucoma is one of the most common causes of irreversible blindness. It is acknowledged that lowering intraocular pressure (IOP) is the effective treatment to slow glaucoma disease progression. The main obstacle of existing drugs is that the effect of reducing IOP does not last long. Degradation of IκB stimulates the transcription of NF-κB, which could upregulate the expression of matrix metalloproteinases (MMPs). Whether a IκB-targeted gene therapy works in glaucoma is unclear. Here, we established a chronic ocular hypertension (COHT) model in rhesus monkey by laser photocoagulation and verified that intracameral delivery of IκBα-siRNA showed long-lasting and potent effects of reducing IOP without obvious inflammation in monkeys with COHT. We also verified that IκBα-siRNA could increase the expressions of MMP2 and MMP9 by knocking down IκBα in vitro and in vivo. Our results in nonhuman primates indicated that IκBα-siRNA may become a promising therapeutic approach for the treatment of glaucoma. Knocking down IκBα could upregulate the expression of MMP2 and MMP9 in MCM and MTM LP could induce COHT model in rhesus monkeys successfully IκBα-siRNA has a long-term and potent IOP-lowering effect in LP-induced monkeys with COHT
Collapse
Affiliation(s)
- Difang Sun
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Zongyi Zhan
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Rui Zeng
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Xiaolin Liu
- Guangdong Provincial Key Laboratory of Laboratory Animals, Guangdong Laboratory Animals Monitoring Institute, Guangdong Laboratory Animals Monitoring Institute, Guangzhou, China
| | - Bin Wang
- Department of Sports Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Fan Yang
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Sa Huang
- Guangdong Provincial Key Laboratory of Laboratory Animals, Guangdong Laboratory Animals Monitoring Institute, Guangdong Laboratory Animals Monitoring Institute, Guangzhou, China
| | - Yunfeng Li
- Guangdong Provincial Key Laboratory of Laboratory Animals, Guangdong Laboratory Animals Monitoring Institute, Guangdong Laboratory Animals Monitoring Institute, Guangzhou, China
| | - Zhenlan Yang
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yuanyuan Su
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yuqing Lan
- Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| |
Collapse
|
6
|
Kumar S, Benavente-Perez A, Ablordeppey R, Lin C, Viswanathan S, Akopian A, Bloomfield SA. A Robust Microbead Occlusion Model of Glaucoma for the Common Marmoset. Transl Vis Sci Technol 2022; 11:14. [PMID: 35019964 PMCID: PMC8762714 DOI: 10.1167/tvst.11.1.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To establish a robust experimental model of glaucoma in the common marmoset (Callithrix jacchus), a New World primate, using an intracameral microbead injection technique. Methods Elevated intraocular pressure (IOP) was induced by an injection of polystyrene microbeads. Morphologic changes in the retina and optic nerve of glaucomatous eyes were assessed and electroretinogram (ERG) recordings were performed to evaluate functional changes. Results Microbead injections induced a sustained IOP elevation for at least 10 weeks in a reproducible manner. At the end of the 10-week experimental period, there was significant loss of retinal ganglion cells (RGCs) in all quadrants and eccentricities, although it was more prominent in the mid-peripheral and peripheral regions. This was consistent with a thinning of the Retinal nerve fiber layer (RNFL) seen in spectral domain optical coherence tomography scans. Surviving RGCs showed marked changes in morphology, including somatic shrinkage and dendritic atrophy. Retinas also showed significant gliosis. The amplitude of the ERG photopic negative response, with subsequent a- and b-wave changes, was reduced in glaucomatous eyes. The optic nerve of glaucomatous eyes showed expanded cupping, disorganization of the astrocytic matrix, axonal loss, and gliosis. Conclusions We developed a robust and reproducible model of glaucoma in the marmoset. The model exhibits both structural and functional alterations of retina and optic nerve characteristic of glaucoma in humans and animal models. Translational Relevance The glaucoma model in the marmoset described here forms a robust method to study the disease etiology, progression, and potential therapies in a nonhuman primate, allowing for more effective translation of animal data to humans.
Collapse
Affiliation(s)
- Sandeep Kumar
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Alexandra Benavente-Perez
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Reynolds Ablordeppey
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Carol Lin
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Suresh Viswanathan
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Abram Akopian
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| | - Stewart A Bloomfield
- Department of Biological and Vision Sciences, State University of New York College of Optometry, New York, NY, USA
| |
Collapse
|
7
|
Peng M, Margetts TJ, Sugali CK, Rayana NP, Dai J, Sharma TP, Raghunathan VK, Mao W. An ex vivo model of human corneal rim perfusion organ culture. Exp Eye Res 2022; 214:108891. [PMID: 34896309 PMCID: PMC8792355 DOI: 10.1016/j.exer.2021.108891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/01/2021] [Accepted: 12/05/2021] [Indexed: 01/03/2023]
Abstract
The human anterior segment perfusion culture model is a valuable tool for studying the trabecular meshwork (TM) and aqueous humor outflow in glaucoma. The traditional model relies on whole eye globes resulting in high cost and limited availability. Here, we developed a glue-based method which enabled us to use human corneal rims for perfusion culture experiments. Human corneal rim perfusion culture plates were 3D printed. Human corneal rims containing intact TM were attached and sealed to the plate using low viscosity and high viscosity glues, respectively. The human corneal rims were perfused using the constant flow mode, and the pressure changes were recorded using a computerized system. Outflow facility, TM stiffness, and TM morphology were evaluated. When perfused at rates from 1.2 to 3.6 μl/min, the outflow facility was 0.359 ± 0.216 μl/min/mmHg among 10 human corneal rims. The stiffness of the TM in naïve human corneal rim was similar to that of perfusion cultured human corneal rim. Also, the stiffness of TM of corneal rims perfused with dexamethasone was significantly higher than the control. Human corneal rims with glue contamination in the TM could be differentiated by high baseline intraocular pressure as well as high TM stiffness. Histology studies showed that the TM tissues perfused with plain medium appeared normal. We believed that our glued-based method is a useful tool and low-cost alternative to the traditional anterior segment perfusion culture model.
Collapse
Affiliation(s)
- Michael Peng
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine
| | - Tyler J. Margetts
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine
| | - Chenna Kesavulu Sugali
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine
| | - Naga Pradeep Rayana
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine
| | - Jiannong Dai
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine
| | - Tasneem P. Sharma
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine,Department of Pharmacology and Toxicology, Indiana University School of Medicine
| | - Vijay Krishna Raghunathan
- The Ocular Surface Institute, Department of Basic Sciences, College of Optometry, University of Houston,Department of Biomedical Engineering, Cullen College of Engineering, University of Houston
| | - Weiming Mao
- Eugene & Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine,Department of Pharmacology and Toxicology, Indiana University School of Medicine,Department of Biochemistry and Molecular Biology, Indiana University School of Medicine
| |
Collapse
|
8
|
Lin KH, Tran T, Kim S, Park S, Stout JT, Chen R, Rogers J, Yiu G, Thomasy S, Moshiri A. Advanced Retinal Imaging and Ocular Parameters of the Rhesus Macaque Eye. Transl Vis Sci Technol 2021; 10:7. [PMID: 34111251 PMCID: PMC8107642 DOI: 10.1167/tvst.10.6.7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine the range of normal ocular biometry and perform advanced retinal imaging and functional assessment of the rhesus macaque eye. Methods We performed ocular phenotyping on rhesus macaques at the California National Primate Research Center. This process consisted of anterior and posterior segment eye examination by ophthalmologists, advanced retinal imaging, and functional retinal electrophysiology. Results Full eye examinations were performed on 142 animals, consisting of pupillary light reflex, tonometry, external examination and photography, anterior slit lamp examination, and posterior segment examination by indirect ophthalmoscopy. Ages of the rhesus macaques ranged from 0.7 to 29 years (mean, 16.4 ± 7.5 years). Anterior segment measurements such as intraocular pressure (n = 142), corneal thickness (n = 84), lens thickness (n = 114), and axial length (n = 114) were acquired. Advanced retinal imaging in the form of fundus photography (n = 78), optical coherence tomography (n = 60), and quantitative autofluorescence (n = 44) was obtained. Electroretinography (n = 75) was used to assay retinal function. Quantitative analyses of the macular structure, retinal layer segmentation, and rod and cone photoreceptor electrical responses are reported. Quantitative assessments were made and variations between sexes were analyzed to compare with established sex changes in human eyes. Conclusions The rhesus macaque has an ocular structure and function very similar to that of the human eye. In particular macular structure and retinal function is very similar to humans, making this species particularly useful for the study of macular biology and development of therapies for cone photoreceptor disorders. Translational Relevance Rhesus macaques are an ideal model for future vision science studies of human eye diseases.
Collapse
Affiliation(s)
- Kira H Lin
- William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - Tu Tran
- Department of Ophthalmology & Vision Science, School of Medicine, University of California-Davis, Sacramento, CA, USA
| | - Soohyun Kim
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - Sangwan Park
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - J Timothy Stout
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, TX, USA
| | - Rui Chen
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
| | - Jeffrey Rogers
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Glenn Yiu
- Department of Ophthalmology & Vision Science, School of Medicine, University of California-Davis, Sacramento, CA, USA
| | - Sara Thomasy
- Department of Ophthalmology & Vision Science, School of Medicine, University of California-Davis, Sacramento, CA, USA.,Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, CA, USA
| | - Ala Moshiri
- Department of Ophthalmology & Vision Science, School of Medicine, University of California-Davis, Sacramento, CA, USA
| |
Collapse
|
9
|
Hyperbranched Cationic Glycogen Derivative-Mediated I κB α Gene Silencing Regulates the Uveoscleral Outflow Pathway in Rats. BIOMED RESEARCH INTERNATIONAL 2021; 2020:8206849. [PMID: 33381584 PMCID: PMC7762656 DOI: 10.1155/2020/8206849] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 09/04/2020] [Accepted: 11/18/2020] [Indexed: 12/31/2022]
Abstract
The role of the IκB/NF-κB signaling pathway in the uveoscleral outflow pathway was investigated with IκBα gene silencing mediated by the 3-(dimethylamino)-1-propylamine-conjugated glycogen (DMAPA-Glyp) derivative. The IκBα-siRNA-loaded DMAPA-Glyp complex was transfected into the ciliary muscles of rats by intracameral injection (labeled as the DMAPA-Glyp+siRNA group). The Lipofectamine™ 2000 (Lipo)/siRNA complex and the naked siRNA were set as the controls. The mRNA and protein expression of IκBα, NF-κBp65, and MMP-2 were analyzed by real-time PCR, western blotting, and in situ gelatin zymography. Nuclear translocation of NF-κBp65 was analyzed by immunofluorescence. Rat intraocular pressure (IOP) was monitored pre- and postinjection. Gene transfection efficiency and toxicity of the DMAPA-Glyp derivative were also evaluated. After RNA interference (RNAi), IκBα mRNA and protein expression were significantly inhibited. NF-κBp65 mRNA and protein expression showed no significant differences. Nevertheless, nuclear translocation of NF-κBp65 occurred in the DMAPA-Glyp+siRNA group. Both mRNA expression and activity of MMP-2 increased, with the largest increase in the DMAPA-Glyp+siRNA group. IOP in the DMAPA-Glyp+siRNA group fell to the lowest level on day 3 after RNAi. The levels of Cy3-siRNA in the ciliary muscle of the DMAPA-Glyp+siRNA group did not significantly decrease over time. At 7 and 14 d after RNAi, no significant pathological damage was detectable in the eyes injected with the DMAPA-Glyp derivative or the DMAPA-Glyp/siRNA complex. Taken together, our results suggest that downregulation of IκBα expression in the ciliary muscle plays a crucial role in reducing the IOP values of rats. IκBα may become a new molecular target for lowering IOP in glaucoma. The DMAPA-Glyp derivative is safe and feasible as an effective siRNA vector in rat eyes.
Collapse
|
10
|
Chan ASY, Tun TA, Allen JC, Lynn MN, Tun SBB, Barathi VA, Girard MJA, Aung T, Aihara M. Longitudinal assessment of optic nerve head changes using optical coherence tomography in a primate microbead model of ocular hypertension. Sci Rep 2020; 10:14709. [PMID: 32895414 PMCID: PMC7477239 DOI: 10.1038/s41598-020-71555-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/19/2020] [Indexed: 11/16/2022] Open
Abstract
In humans, the longitudinal characterisation of early optic nerve head (ONH) damage in ocular hypertension (OHT) is difficult as patients with glaucoma usually have structural ONH damage at the time of diagnosis. Previous studies assessed glaucomatous ONH cupping by measuring the anterior lamina cribrosa depth (LCD) and minimal rim width (MRW) using optical coherence tomography (OCT). In this study, we induced OHT by repeated intracameral microbead injections in 16 cynomolgus primates (10 unilateral; 6 bilateral) and assessed the structural changes of the ONH longitudinally to observe early changes. Elevated intraocular pressure (IOP) in OHT eyes was maintained for 7 months and serial OCT measurements were performed during this period. The mean IOP was significantly elevated in OHT eyes when compared to baseline and compared to the control eyes. Thinner MRW and deeper LCD values from baseline were observed in OHT eyes with the greatest changes seen between month 1 and month 2 of OHT. Both the mean and maximum IOP values were significant predictors of MRW and LCD changes, although the maximum IOP was a slightly better predictor. We believe that this model could be useful to study IOP-induced early ONH structural damage which is important for understanding glaucoma pathogenesis.
Collapse
Affiliation(s)
- Anita S Y Chan
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore. .,Department of Ophthalmology, University of Tokyo, Tokyo, Japan.
| | - Tin Aung Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | | | - Myoe Naing Lynn
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Sai Bo Bo Tun
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore
| | - Veluchamy Amutha Barathi
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Michaël J A Girard
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Ophthalmic Engineering & Innovation Laboratory (OEIL), Singapore Eye Research Institute, Singapore, Singapore
| | - Tin Aung
- Singapore Eye Research Institute and Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore, 168751, Singapore.,Duke-NUS Medical School, Singapore, Singapore.,Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Makoto Aihara
- Department of Ophthalmology, University of Tokyo, Tokyo, Japan
| |
Collapse
|
11
|
Wu J, Bell OH, Copland DA, Young A, Pooley JR, Maswood R, Evans RS, Khaw PT, Ali RR, Dick AD, Chu CJ. Gene Therapy for Glaucoma by Ciliary Body Aquaporin 1 Disruption Using CRISPR-Cas9. Mol Ther 2020; 28:820-829. [PMID: 31981492 PMCID: PMC7054720 DOI: 10.1016/j.ymthe.2019.12.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 12/22/2019] [Accepted: 12/30/2019] [Indexed: 02/07/2023] Open
Abstract
Glaucoma is a common cause of blindness, yet current therapeutic options are imperfect. Clinical trials have invariably shown that reduction in intraocular pressure (IOP) regardless of disease subtype prevents visual loss. Reducing ciliary body aqueous humor production can lower IOP, and the adeno-associated virus ShH10 serotype was identified as able to transduce mouse ciliary body epithelium following intravitreal injection. Using ShH10 to deliver a single vector CRISPR-Cas9 system disrupting Aquaporin 1 resulted in reduced IOP in treated eyes (10.4 ± 2.4 mmHg) compared with control (13.2 ± 2.0 mmHg) or non-injected eyes (13.1 ± 2.8 mmHg; p < 0.001; n = 12). Editing in the aquaporin 1 gene could be detected in ciliary body, and no off-target increases in corneal or retinal thickness were identified. In experimental mouse models of corticosteroid and microbead-induced ocular hypertension, IOP could be reduced to prevent ganglion cell loss (32 ± 4 /mm2) compared with untreated eyes (25 ± 5/mm2; p < 0.01). ShH10 could transduce human ciliary body from post-mortem donor eyes in ex vivo culture with indel formation detectable in the Aquaporin 1 locus. Clinical translation of this approach to patients with glaucoma may permit long-term reduction of IOP following a single injection.
Collapse
Affiliation(s)
- Jiahui Wu
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK; Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - Oliver H Bell
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - David A Copland
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Alison Young
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - John R Pooley
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Ryea Maswood
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Rachel S Evans
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0PY, UK
| | - Peng Tee Khaw
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London EC1V 2PD, UK
| | - Robin R Ali
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London EC1V 2PD, UK
| | - Andrew D Dick
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK; UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre for Ophthalmology at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London EC1V 2PD, UK
| | - Colin J Chu
- Translational Health Sciences, University of Bristol, Bristol BS8 1TD, UK.
| |
Collapse
|
12
|
Towards A Microbead Occlusion Model of Glaucoma for a Non-Human Primate. Sci Rep 2019; 9:11572. [PMID: 31399621 PMCID: PMC6689098 DOI: 10.1038/s41598-019-48054-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 07/27/2019] [Indexed: 12/16/2022] Open
Abstract
Glaucoma is a group of optic neuropathies associated with aging and sensitivity to intraocular pressure (IOP). The disease causes vision loss through the degeneration of retinal ganglion cell neurons and their axons in the optic nerve. Using an inducible model of glaucoma, we elevated IOP in the squirrel monkey (Saimiri boliviensis) using intracameral injection of 35 μm polystyrene microbeads and measured common pathogenic outcomes in the optic projection. A 42% elevation in IOP over 28 weeks reduced anterograde transport of fluorescently-labeled cholera toxin beta from retina to the lateral geniculate nucleus (60% decrease), and to the superior colliculus (49% decrease). Pressure also reduced survival of ganglion cellaxons in the optic nerve by 22%. The same elevation caused upregulation of proteins associated with glaucomatous neurodegeneration in the retina and optic nerve, including complement 1q, interleukin 6, and brain-derived neurotrophic factor. That axon degeneration in the nerve lagged deficits in anterograde transport is consistent with progression in rodent models, while the observed protein changes also occur in tissue from human glaucoma patients. Thus, microbead occlusion in a non-human primate with a visual system similar to our own represents an attractive model to investigate neurodegenerative mechanisms and therapeutic interventions for glaucoma.
Collapse
|
13
|
Lozano DC, Choe TE, Cepurna WO, Morrison JC, Johnson EC. Early Optic Nerve Head Glial Proliferation and Jak-Stat Pathway Activation in Chronic Experimental Glaucoma. Invest Ophthalmol Vis Sci 2019; 60:921-932. [PMID: 30835784 PMCID: PMC6402265 DOI: 10.1167/iovs.18-25700] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 01/25/2019] [Indexed: 12/18/2022] Open
Abstract
PURPOSE We previously reported increased expression of cell proliferation and Jak-Stat pathway-related genes in chronic experimental glaucoma model optic nerve heads (ONH) with early, mild injury. Here, we confirm these observations by localizing, identifying, and quantifying ONH cellular proliferation and Jak-Stat pathway activation in this model. METHODS Chronic intraocular pressure (IOP) elevation was achieved via outflow pathway sclerosis. After 5 weeks, ONH longitudinal sections were immunolabeled with proliferation and cell-type markers to determine nuclear densities in the anterior (unmyelinated) and transition (partially myelinated) ONH. Nuclear pStat3 labeling was used to detect Jak-Stat pathway activation. Nuclear density differences between control ONH (uninjected) and ONH with either early or advanced injury (determined by optic nerve injury grading) were identified by ANOVA. RESULTS Advanced injury ONH had twice the nuclear density (P < 0.0001) of controls and significantly greater astrocyte density in anterior (P = 0.0001) and transition (P = 0.006) ONH regions. An increased optic nerve injury grade positively correlated with increased microglia/macrophage density in anterior and transition ONH (P < 0.0001, both). Oligodendroglial density was unaffected. In glaucoma model ONH, 80% of anterior and 66% of transition region proliferating cells were astrocytes. Nuclear pStat3 labeling significantly increased in early injury anterior ONH, and 95% colocalized with astrocytes. CONCLUSIONS Astrocytes account for the majority of proliferating cells, contributing to a doubled nuclear density in advanced injury ONH. Jak-Stat pathway activation is apparent in the early injury glaucoma model ONH. These data confirm dramatic astrocyte cell proliferation and early Jak-Stat pathway activation in ONH injured by elevated IOP.
Collapse
Affiliation(s)
- Diana C. Lozano
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Tiffany E. Choe
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - William O. Cepurna
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - John C. Morrison
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Elaine C. Johnson
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| |
Collapse
|
14
|
Abstract
SIGNIFICANCE For glaucoma patients, high intraocular pressure (IOP) is a risk factor for progressive neuropathy. Similarly, animal models used to study the disease are based on an experimental elevation of IOP. Thus, accurate IOP measurements are important in characterizing experimental models and resulting effects. PURPOSE The purpose of the present study was to investigate IOP measurements in a non-human primate model of experimental glaucoma by comparing clinical tonometry (Tono-Pen and TonoVet) to the true IOP from intracameral manometry. METHODS A total of 17 rhesus macaque eyes from 12 animals were used for this study. Eleven eyes had no previous experimental intervention, whereas six eyes were at varying stages of laser-induced experimental glaucoma. IOPs were adjusted by inserting a needle in the anterior chamber that was attached to a pressure transducer and syringe pump system. The anterior chamber IOP was adjusted to values between 10 and 50 mmHg and corresponding measures with Tono-Pen and TonoVet were taken. RESULTS The IOPs by TonoVet and Tono-Pen were linearly related over the range of pressures tested (slope = 0.68 normal/healthy and 0.72 experimental glaucoma). For the most, TonoVet measures overestimated IOP at all anterior chamber pressure settings (mean difference of 3.17 mmHg, 95% CI 12.53 to -4.74 normal and 3.90 mmHg, 95% CI 12.90 to -6.53 experimental glaucoma). In contrast, Tono-Pen measures overestimated IOP at lower IOPs and underestimated at higher IOP (slope = -0.26 normal and -0.21 experimental glaucoma). CONCLUSIONS The TonoVet and Tono-Pen tonometers that are often used to assess IOP in both clinical and experimental settings generally reflect the status of IOP, but the results from this study suggest that the instruments need calibration with true anterior chamber pressure for accurate measures in experimental models of glaucoma.
Collapse
|
15
|
Dai M, Zhang Q, Zheng Z, Wang J. Retinal ganglion cell-conditioned medium and surrounding pressure alters gene expression and differentiation of rat retinal progenitor cells. Mol Med Rep 2018; 17:7177-7183. [PMID: 29568879 PMCID: PMC5928676 DOI: 10.3892/mmr.2018.8738] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 12/04/2017] [Indexed: 12/13/2022] Open
Abstract
Loss of retinal ganglion cells is implicated in glaucoma and high intraocular pressure. Factors that affect the differentiation of retinal progenitor cells into retinal ganglion cells remain unclear. The present study aimed to investigate the effects of retinal ganglion cell‑conditioned medium on gene expression and differentiation in retinal progenitor cells, and the effects of surrounding pressure on the survival and differentiation of retinal progenitor cells. Retinal progenitor cells and retinal ganglion cells were isolated from rats. Immunofluorescence staining of Nestin and Thy1 was performed to identify rat retinal progenitor cells and retinal ganglion cells, respectively. Retinal progenitor cells and ganglion cells were cultured for 48 h under surrounding pressure of 0, 20, 40, 60 and 80 mmHg. Cellular apoptosis was detected using a caspase‑3 assay kit. In addition, the culture supernatant of rat retinal ganglion cells was collected. Retinal progenitor cells were cultured in the presence or absence of retinal ganglion‑conditioned medium for 72 h under normal pressure. Gene expression of Nestin, paired box protein 6 (PAX6), Thy1 and brain‑specific homeobox/POU domain protein 3 (Brn‑3) in retinal progenitor cells was detected by reverse transcription‑quantitative polymerase chain reaction. Retinal progenitor cells were cultured in retinal ganglion‑conditioned medium for 72 h under surrounding pressure of 0 and 40 mmHg, respectively, and flow cytometry was utilized to evaluate the effects of pressure on the differentiation of retinal progenitor cells into retinal ganglion cells. The results demonstrated that isolated retinal progenitor cells were Nestin‑positive and retinal ganglion cells were Thy1‑positive, suggesting successful isolation. The activity of caspase‑3 increased in retinal progenitor cells and retinal ganglion cells in a pressure‑dependent manner. When the surrounding pressure reached 40, 60 and 80 mmHg, the activity of caspase‑3 in retinal progenitor cells and ganglion cells increased significantly compared with cells that were not under pressure. Compared with retinal progenitor cells cultured without ganglion‑conditioned medium, those cultured with ganglion‑conditioned medium had significantly decreased expression levels of Nestin and PAX6, and increased expression levels of Thy1 and Brn3. Compared with 0 mmHg pressure, retinal progenitor cells cultured in ganglion‑conditioned medium under 40 mmHg pressure had increased percentages of Thy1‑positive cells. In conclusion, the apoptosis of rat retinal progenitor cells and retinal ganglion cells was pressure‑dependent. Retinal ganglion cell‑conditioned medium increased the differentiation of retinal progenitor cells into retinal ganglion‑like cells, and the differentiation increased as surrounding pressure increased. Current study provides insights that may contribute to the efforts of developing a treatment for glaucoma.
Collapse
Affiliation(s)
- Min Dai
- Department of Ophthalmology, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
| | - Qing Zhang
- Department of Ophthalmology, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
| | - Zhikun Zheng
- Department of Ophthalmology, Second People's Hospital of Yunnan Province, Kunming, Yunan 650021, P.R. China
| | - Jianzhou Wang
- Department of Ophthalmology, Yan'an Hospital, Kunming, Yunan 650051, P.R. China
| |
Collapse
|
16
|
Lee JS, Lee CE, Park JH, Seo S, Lee KW. Refractive Error Induced by Combined Phacotrabeculectomy. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2018. [DOI: 10.3341/jkos.2018.59.12.1173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
| | - Chong Eun Lee
- Department of Ophthalmology, Keimyung University School of Medicine, Daegu, Korea
| | | | - Sam Seo
- Cheil Eye Hospital, Daegu, Korea
| | | |
Collapse
|
17
|
Bui BV. Understanding glaucoma pathogenesis. Clin Exp Ophthalmol 2017; 45:853. [DOI: 10.1111/ceo.13072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bang V Bui
- Department of Optometry and Vision Sciences; The University of Melbourne; Melbourne Victoria Australia
| |
Collapse
|
18
|
Paiva ADCM, da Fonseca ADS. Could adverse effects and complications of selective laser trabeculoplasty be decreased by low-power laser therapy? Int Ophthalmol 2017; 39:243-257. [PMID: 29189945 DOI: 10.1007/s10792-017-0775-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 11/24/2017] [Indexed: 12/19/2022]
Abstract
Selective laser trabeculoplasty (SLT) has been used for treatment of primary open-angle glaucoma, ocular hypertension, pigmenter and pseudoexfoliative glaucoma being considered a low-risk procedure. Therefore, transitory and permanent adverse effects have been reported, including corneal changes, subclinical edema, and reduction in endothelial cells and in central corneal thickness. Despite rarer, serious corneal complications after SLT can be permanent and lead to visual impairment, central corneal haze, opacity and narrowing. The mechanism involves increase of vasoactive and chemotactic cytokines causing inflammatory infiltrate, destruction of stromal collagen by fibroblasts and increase of matrix metalloproteinases type 2, which impair reepithelization. SLT also increases free radical production and reduces antioxidant enzymes, resulting in endothelium damages. Low-power laser therapy (LPLT) has been used in regenerative medicine based on its biostimulatory and anti-inflammatory effects. Biostimulation occurs through the interaction of laser photons with cytochrome C oxidase enzyme, which activates intracellular biochemical cascades causing synthesis of a number of molecules related to anti-inflammatory, regenerative effects, pain relief and reduction in edema. It has been showed that LPLT reduces gene expression related to pro-inflammatory cytokines and matrix metalloproteinases, and it increases expression of growth factors related to its proliferative and healing actions. Although radiations emitted by low-power lasers are considered safe and able to induce therapeutic effects, researches based on experimental models for glaucoma could bring important data if LPLT could be an alternative approach to improve acceptation for patients undergoing SLT.
Collapse
Affiliation(s)
- Alexandre de Carvalho Mendes Paiva
- Departamento de Ciências Fisiológicas, Instituto Biomédico, Universidade Federal do Estado do Rio de Janeiro, Rua Frei Caneca, 94, Centro, Rio de Janeiro, 20211040, Brazil
| | - Adenilson de Souza da Fonseca
- Departamento de Ciências Fisiológicas, Instituto Biomédico, Universidade Federal do Estado do Rio de Janeiro, Rua Frei Caneca, 94, Centro, Rio de Janeiro, 20211040, Brazil. .,Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Boulevard Vinte e Oito de Setembro, 87 fundos, 4º andar, Vila Isabel, Rio de Janeiro, 20551030, Brazil. .,Centro de Ciências da Saúde, Centro Universitário Serra dos Órgãos, Avenida Alberto Torres, 111, Teresópolis, Rio de Janeiro, 25964004, Brazil.
| |
Collapse
|
19
|
Jasien JV, Huisingh C, Girkin CA, Downs JC. The Magnitude of Hypotony and Time Course of Intraocular Pressure Recovery Following Anterior Chamber Cannulation in Nonhuman Primates. Invest Ophthalmol Vis Sci 2017; 58:3225-3230. [PMID: 28660275 PMCID: PMC5490360 DOI: 10.1167/iovs.17-21833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Purpose To determine the magnitude of ocular hypotony and the length of recovery time to 6 and 10 mm Hg IOP following anterior chamber (AC) cannulation. Methods Bilateral IOP was recorded 500 times per second via telemetry immediately before, during, and immediately after AC cannulation with a 27-G needle in 10 different sessions at least 2 weeks apart in four male rhesus macaques (nonhuman primates; NHPs) aged 3- to 6-years old. Bilateral IOP was recorded continuously using a proven telemetry system while the NHPs were under general anesthesia during IOP transducer calibration experiments involving manometric control of IOP via AC cannulation, then continuously after the AC needles were removed until IOP recovered to precannulation levels. The change in IOP from baseline to AC cannulation was tested using the signed-rank test. The times necessary for IOP to recover to 6 and 10 mm Hg, respectively, were calculated. Results Average precannulation IOP was 11.5 mm Hg and significantly decreased to an average of 2.3 mm Hg immediately following AC needle removal (P = 0.0156). On average, IOP recovered from 2.3 to 6 and 10 mm Hg in 32.4 and 63.7 minutes, respectively. Recovery times of IOP were not affected by repeated AC cannulations every 2 weeks. Conclusions Generally, IOP recovers relatively quickly after repeated AC cannulation, and did not result in extended duration hypotony. It is important to consider hypotony in animal experiments and clinical procedures involving AC cannulation and paracentesis when consideration of IOP or its effects is important.
Collapse
Affiliation(s)
- Jessica V Jasien
- Vision Science Graduate Program, School of Optometry, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Carrie Huisingh
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - Christopher A Girkin
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| | - J Crawford Downs
- Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States
| |
Collapse
|
20
|
Chen L, Zhao Y, Zhang H. Comparative Anatomy of the Trabecular Meshwork, the Optic Nerve Head and the Inner Retina in Rodent and Primate Models Used for Glaucoma Research. Vision (Basel) 2016; 1:vision1010004. [PMID: 31740629 PMCID: PMC6848998 DOI: 10.3390/vision1010004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/26/2016] [Accepted: 07/08/2016] [Indexed: 12/13/2022] Open
Abstract
Glaucoma is a heterogeneous group of ocular disorders with a multi-faceted etiology. Although numerous studies on glaucoma using different animal models have been published, it is unwise to simply generalize the results of one model to all glaucomatous situations because of the differences in the anatomy and morphology of animal eyes in comparison with humans’. In this review, we highlight the differences in the trabecular meshwork (TM) tissue, lamina cribrosa (LC) region, optic nerve head (ONH) and the inner layer of the retina in mice, rats and monkeys. In comparison with humans, non-human primates show TM, retina and ONH that are anatomically almost identical. The rat model shows many similarities in the aqueous outflow pathway compared to humans. The mouse ONH lacks collagenous LC, and this finding is observed across different mouse strains. The tissue structure of the ONH in rodents is similar to that in humans, although the blood supply shows differences. The number of cells in the ganglion layer depends on the rodent strain. Despite some differences from humans, rodents are a good choice for studying different types of glaucoma, and the modeling method should be selected based on the experimental needs and the hypothesis being tested.
Collapse
Affiliation(s)
| | | | - Hong Zhang
- Correspondence: ; Tel.: +86-139-7167-9079; Fax: +86-027-8366-3688
| |
Collapse
|
21
|
Liu K, Wang N, Peng X, Yang D, Wang C, Zeng H. Long-term effect of laser-induced ocular hypertension on the cone electroretinogram and central macular thickness in monkeys. Photomed Laser Surg 2016; 32:371-8. [PMID: 24992271 DOI: 10.1089/pho.2013.3693] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE The purpose of this study was to investigate the long-term effect of laser-induced ocular hypertension on the cone electroretinogram (ERG) and retinal thickness in monkeys. BACKGROUND DATA Degeneration of retinal nerve fiber layer (RNFL) and loss of retinal ganglion cells in the primate glaucoma model have been confirmed by histological studies and optical coherence tomography (OCT) images. However, it remains unclear whether the outer retina distal to the RGCs (e.g., photoreceptors) is involved in histological studies and in functional test. MATERIALS AND METHODS Subjects were five monkeys with high intraocular pressure (IOP) induced in the right eye by laser. Six years after the laser coagulation of the mid-trabecular meshwork, RNFL, ganglion cell complex (GCC), central macular thickness (CMT), and the thickness of outer retinal layer (ORL) were measured by OCT. The photopic responses of ERG were recorded in response to red flashes on a blue background. The maximum cone amplitude (Rcone) and cone sensitivity (Scone) were calculated. RESULTS Enlarged cup-to-disc (C/D) ratio was found in the lasered eyes. RNFL and GCC were significantly thinner in the lasered eyes (p<0.05), but no significant differences were found in CMT and the thickness of ORL compared with fellow eyes (p>0.05). Mean amplitude of the photopic negative response (PhNR), Mean Rcone were significantly lower in the lasered eye (p<0.05), and no significant differences of Scone were found between the two eyes (p>0.05). CONCLUSIONS Long-term ocular hypertension induced by laser affects the function of cone photoreceptor in monkeys.
Collapse
Affiliation(s)
- Kegao Liu
- 1 Beijing Ophthalmology and Visual Science Key Laboratory, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University , Beijing, China
| | | | | | | | | | | |
Collapse
|
22
|
Immune phenomena in glaucoma and conformational disorders: why is the second eye not involved? J Glaucoma 2015; 23:S59-61. [PMID: 25275909 DOI: 10.1097/ijg.0000000000000115] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Data along several lines of evidence have suggested that a systemic autoimmune response may be provoked in glaucoma and could contribute to retinal ganglion cell loss. If such an autoimmune response exists, one could predict that in cases of unilateral glaucoma, autoantibodies generated would affect both eyes, leading to damage in the unaffected, contralateral eye in an intraocular pressure-independent manner. However, such an effect has not yet been reported. There are currently no data to reconcile these contrasting observations but a review of the literature suggests a possible explanation.
Collapse
|
23
|
Patel NB, Sullivan-Mee M, Harwerth RS. The relationship between retinal nerve fiber layer thickness and optic nerve head neuroretinal rim tissue in glaucoma. Invest Ophthalmol Vis Sci 2014; 55:6802-16. [PMID: 25249610 DOI: 10.1167/iovs.14-14191] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The purpose of this study was to determine the relationship between optical coherence tomography (OCT) measures of retinal nerve fiber layer (RNFL) and neuroretinal rim (NRR) in a nonhuman primate experimental glaucoma model, and in a population of clinical patients. METHODS For nonhuman primates, normative data were collected from 44 healthy monkeys, and nine animals with unilateral experimental glaucoma that were followed longitudinally. Cross-sectional human subjects data were collected from 89 healthy, 74 glaucoma suspects, and 104 glaucoma patients. Individualized transverse scaling for OCT scans was calculated using a schematic eye that incorporated optical ocular biometry. Custom algorithms were used to quantify RNFL thickness with and without vessels removed, scaled minimum rim width (sMRW), and neural rim volume (NRV). RESULTS For the experimental glaucoma group, NRR parameters showed the first changes with increased cumulative IOP. The data for both NRR and RNFL measures were best fit by an exponential rise model (NRV, R2=0.79, P<0.01, sMRW, R2=0.74, P<0.01). The major retinal vascular thickness contribution to the RNFL decreased (0.03 μm/μm, P<0.01) with RNFL loss, but the percent vascular contribution increased (-0.1%/μm, P<0.01) with disease progression. Overall, the findings for the cross-sectional human data were similar to those of the experimental model. CONCLUSIONS The findings illustrate a nonlinear relationship between NRR and RNFL measures and provide support for the use of multiple OCT scaled morphological measures for the diagnosis and management of primary open angle glaucoma in humans.
Collapse
Affiliation(s)
- Nimesh B Patel
- Department of Vision Sciences, University of Houston College of Optometry, Houston, Texas, United States
| | - Michael Sullivan-Mee
- New Mexico Veterans Affairs Health Care System, Albuquerque VA Medical Center, Albuquerque, New Mexico, United States
| | - Ronald S Harwerth
- Department of Vision Sciences, University of Houston College of Optometry, Houston, Texas, United States
| |
Collapse
|
24
|
Kagan DB, Gorfinkel NS, Hutnik CML. Mechanisms of selective laser trabeculoplasty: a review. Clin Exp Ophthalmol 2014; 42:675-81. [PMID: 24330092 DOI: 10.1111/ceo.12281] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 11/21/2013] [Indexed: 11/30/2022]
Abstract
Selective laser trabeculoplasty is a safe and effective treatment for glaucoma, with greater cost effectiveness than its pharmacological and surgical alternatives. Nevertheless, although the basic science literature on selective laser trabeculoplasty continues to grow, there remains uncertainty over the mechanism by which laser trabeculoplasty reduces intraocular pressure. To address this uncertainty, the evidence behind several potential biological and mechanical mechanisms of selective laser trabeculoplasty were reviewed. In particular, cytokine secretion, matrix metalloproteinase induction, increased cell division, repopulation of burn sites and macrophage recruitment were discussed. Refining our understanding of these mechanisms is essential both to understanding the pathophysiology of ocular hypertension and developing improved therapies to treat the condition.
Collapse
Affiliation(s)
- Dov B Kagan
- Ivey Eye Institute, St. Joseph's Hospital, London, Ontario, Canada
| | | | | |
Collapse
|
25
|
Differential progression of structural and functional alterations in distinct retinal ganglion cell types in a mouse model of glaucoma. J Neurosci 2013; 33:17444-57. [PMID: 24174678 DOI: 10.1523/jneurosci.5461-12.2013] [Citation(s) in RCA: 183] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Intraocular pressure (IOP) elevation is a principal risk factor for glaucoma. Using a microbead injection technique to chronically raise IOP for 15 or 30 d in mice, we identified the early changes in visual response properties of different types of retinal ganglion cells (RGCs) and correlated these changes with neuronal morphology before cell death. Microbead-injected eyes showed reduced optokinetic tracking as well as cell death. In such eyes, multielectrode array recordings revealed that four RGC types show diverse alterations in their light responses upon IOP elevation. OFF-transient RGCs exhibited a more rapid decline in both structural and functional organizations compared with other RGCs. In contrast, although the light-evoked responses of OFF-sustained RGCs were perturbed, the dendritic arbor of this cell type remained intact. ON-transient and ON-sustained RGCs had normal functional receptive field sizes but their spontaneous and light-evoked firing rates were reduced. ON- and OFF-sustained RGCs lost excitatory synapses across an otherwise structurally normal dendritic arbor. Together, our observations indicate that there are changes in spontaneous activity and light-evoked responses in RGCs before detectable dendritic loss. However, when dendrites retract, we found corresponding changes in receptive field center size. Importantly, the effects of IOP elevation are not uniformly manifested in the structure and function of diverse RGC populations, nor are distinct RGC types perturbed within the same time-frame by such a challenge.
Collapse
|
26
|
Deng S, Wang M, Yan Z, Tian Z, Chen H, Yang X, Zhuo Y. Autophagy in retinal ganglion cells in a rhesus monkey chronic hypertensive glaucoma model. PLoS One 2013; 8:e77100. [PMID: 24143204 PMCID: PMC3797129 DOI: 10.1371/journal.pone.0077100] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 08/27/2013] [Indexed: 11/19/2022] Open
Abstract
Primary open angle glaucoma (POAG) is a neurodegenerative disease characterized by physiological intraocular hypertension that causes damage to the retinal ganglion cells (RGCs). In the past, RGC damage in POAG was suggested to have been attributed to RGC apoptosis. However, in the present study, we applied a model closer to human POAG through the use of a chronic hypertensive glaucoma model in rhesus monkeys to investigate whether another mode of progressive cell death, autophagy, was activated in the glaucomatous retinas. First, in the glaucomatous retinas, the levels of LC3B-II, LC3B-II/LC3B-I and Beclin 1 increased as demonstrated by Western blot analyses, whereas early or initial autophagic vacuoles (AVi) and late or degraded autophagic vacuoles (AVd) accumulated in the ganglion cell layer (GCL) and in the inner plexiform layer (IPL) as determined by transmission electron microscopy (TEM) analysis. Second, lysosome activity and autophagosome-lysosomal fusion increased in the RGCs of the glaucomatous retinas, as demonstrated by Western blotting against lysosome associated membrane protein-1 (LAMP1) and double labeling against LC3B and LAMP1. Third, apoptosis was activated in the glaucomatous eyes with increased levels of caspase-3 and cleaved caspase-3 and an increased number of TUNEL-positive RGCs. Our results suggested that autophagy was activated in RGCs in the chronic hypertensive glaucoma model of rhesus monkeys and that autophagy may have potential as a new target for intervention in glaucoma treatment.
Collapse
Affiliation(s)
- Shuifeng Deng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Mei Wang
- Sun Yat-Sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Zhichao Yan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Zhen Tian
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Hongrui Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Xuejiao Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
| | - Yehong Zhuo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, People’s Republic of China
- * E-mail:
| |
Collapse
|
27
|
Affiliation(s)
- Caroline J. Zeiss
- Section of Comparative Medicine; Yale University School of Medicine; 375 Congress Ave New Haven CT 06520 USA
| |
Collapse
|
28
|
Alon S. Selective Laser Trabeculoplasty: A Clinical Review. J Curr Glaucoma Pract 2013; 7:58-65. [PMID: 26997784 PMCID: PMC4741175 DOI: 10.5005/jp-journals-10008-1139] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 11/29/2012] [Indexed: 11/23/2022] Open
Abstract
UNLABELLED Selective laser trabeculoplasty (SLT) is a safe and effective treatment modality for lowering the intraocular pressure in patients with glaucoma. It achieves its results by selective absorption of energy in the trabecular pigmented cells, sparing adjacent cells and tissues from thermal damage, with minimal morphological tissue alteration following treatment. On the basis of the peer-reviewed medical literature, SLT is efficacious in lowering IOP, as initial treatment or when medical therapy is insufficient in all types of open-angle glaucoma in all races. SLT achieves intraocular pressure reduction similar to that of argon laser trabeculoplasty but without the tissue destruction and side effects. Observed side effects following SLT were almost uniformly transient and minor. We review highlights of recently published studies on the mechanisms and clinical outcome of SLT in order to address frequently raised issues pertinent to SLT in the clinical practice. KEY MESSAGES Selective laser trabeculoplasty is a safe and effective treatment modality for lowering the intraocular pressure in patients with glaucoma. How to cite this article: Alon S. Selective Laser Trabeculoplasty: A Clinical Review. J Current Glau Prac 2013; 7(2):58-65.
Collapse
Affiliation(s)
- Skaat Alon
- Goldschleger Eye Institute, Sheba Medical Center, Tel Aviv University, Tel Hashomer, Israel; Glaucoma Clinical Fellow, New York Eye and Ear Infirmary, New York, USA
| |
Collapse
|
29
|
|
30
|
Gilger BC, Abarca E, Salmon JH. Selection of Appropriate Animal Models in Ocular Research: Ocular Anatomy and Physiology of Common Animal Models. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2013. [DOI: 10.1007/7653_2013_2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
31
|
Abstract
The Eye chapter of the 3rd edition of Haschek and Rousseaux’s Handbook of Toxicologic Pathology brings a comprehensive description of pathological processes affecting the ocular tissues in the most commonly used laboratory animals and their correlations with human diseases of interest in toxicology. Also presented are detailed descriptions of the structure and function of the different ocular tissues, the most advanced techniques applied in the toxicological evaluation of the eye, useful animal models of human disease, and known mechanisms of ocular toxicity. The introductory sections of the chapter also feature such essential topics as ocular embryology, an overview of clinical ophthalmic evaluation, and eye-specific techniques of tissue processing.
Collapse
|
32
|
Animal models of glaucoma. J Biomed Biotechnol 2012; 2012:692609. [PMID: 22665989 PMCID: PMC3364028 DOI: 10.1155/2012/692609] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 02/27/2012] [Accepted: 02/29/2012] [Indexed: 12/22/2022] Open
Abstract
Glaucoma is a heterogeneous group of disorders that progressively lead to blindness due to loss of retinal ganglion cells and damage to the optic nerve. It is a leading cause of blindness and visual impairment worldwide. Although research in the field of glaucoma is substantial, the pathophysiologic mechanisms causing the disease are not completely understood. A wide variety of animal models have been used to study glaucoma. These include monkeys, dogs, cats, rodents, and several other species. Although these models have provided valuable information about the disease, there is still no ideal model for studying glaucoma due to its complexity. In this paper we present a summary of most of the animal models that have been developed and used for the study of the different types of glaucoma, the strengths and limitations associated with each species use, and some potential criteria to develop a suitable model.
Collapse
|
33
|
Wang Q, Grozdanic SD, Harper MM, Hamouche N, Kecova H, Lazic T, Yu C. Exploring Raman spectroscopy for the evaluation of glaucomatous retinal changes. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:107006. [PMID: 22029368 DOI: 10.1117/1.3642010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Glaucoma is a chronic neurodegenerative disease characterized by apoptosis of retinal ganglion cells and subsequent loss of visual function. Early detection of glaucoma is critical for the prevention of permanent structural damage and irreversible vision loss. Raman spectroscopy is a technique that provides rapid biochemical characterization of tissues in a nondestructive and noninvasive fashion. In this study, we explored the potential of using Raman spectroscopy for detection of glaucomatous changes in vitro. Raman spectroscopic imaging was conducted on retinal tissues of dogs with hereditary glaucoma and healthy control dogs. The Raman spectra were subjected to multivariate discriminant analysis with a support vector machine algorithm, and a classification model was developed to differentiate disease tissues versus healthy tissues. Spectroscopic analysis of 105 retinal ganglion cells (RGCs) from glaucomatous dogs and 267 RGCs from healthy dogs revealed spectroscopic markers that differentiated glaucomatous specimens from healthy controls. Furthermore, the multivariate discriminant model differentiated healthy samples and glaucomatous samples with good accuracy [healthy 89.5% and glaucomatous 97.6% for the same breed (Basset Hounds); and healthy 85.0% and glaucomatous 85.5% for different breeds (Beagles versus Basset Hounds)]. Raman spectroscopic screening can be used for in vitro detection of glaucomatous changes in retinal tissue with a high specificity.
Collapse
Affiliation(s)
- Qi Wang
- Iowa State University, Department of Agricultural and Biosystems Engineering, Ames, Iowa 50011, USA
| | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
Treatment in glaucoma aims to lower intraocular pressure (IOP) to reduce the risk of progression and vision loss. The alpha2-adrenergic receptor agonist brimonidine effectively lowers IOP and is useful as monotherapy, adjunctive therapy, and replacement therapy in open-angle glaucoma and ocular hypertension. A fixed combination of brimonidine and timolol, available in some countries, reduces IOP as effectively as concomitant therapy with brimonidine and timolol and offers the convenience of 2 drugs in a single eyedrop. Brimonidine is safe and well tolerated. Its most common side-effects are conjunctival hyperemia, allergic conjunctivitis, and ocular pruritus. The newest formulation of brimonidine, brimonidine-Purite 0.1%, has a higher pH to improve the ocular bioavailability of brimonidine. This formulation contains the lowest effective concentration of brimonidine and is preserved with Purite(R) to enhance ocular tolerability. Brimonidine-Purite 0.1% is as effective in reducing IOP as the original brimonidine 0.2% solution preserved with benzalkonium chloride. Recent results from preclinical and clinical studies suggest that brimonidine may protect retinal ganglion cells and their projections from damage and death independently of its effects on IOP. The potential for neuroprotection with brimonidine is an added benefit of its use in glaucoma and ocular hypertension.
Collapse
Affiliation(s)
- Louis B Cantor
- Department of Ophthalmology, Indiana University Indianapolis, IN, USA
| |
Collapse
|
35
|
Elsmo EJ, Kiland JA, Kaufman PL, McLellan GJ. Evaluation of rebound tonometry in non-human primates. Exp Eye Res 2011; 92:268-73. [PMID: 21315069 DOI: 10.1016/j.exer.2011.01.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 01/10/2011] [Accepted: 01/28/2011] [Indexed: 11/30/2022]
Abstract
To determine the accuracy and reproducibility of intraocular pressure (IOP) measurements obtained with the TonoVet® rebound tonometer in cynomolgus macaques and to determine the effects of corneal thickness on measurements obtained by the TonoVet®. The anterior chambers of both eyes of anesthetized monkeys were cannulated with branched 23-G needles; one branch was connected to a vertically adjustable reservoir and the other to a pressure transducer. IOP was increased by 5 mmHg increments and then decreased by 10 mmHg decrements. IOP was measured using the TonoVet® at each increment and decrement by 2 independent observers and at every other increment and every decrement by a single observer using 'minified' Goldmann applanation tonometry. Central corneal thickness was measured with a PachPen(TM) ultrasonic pachymeter. TonoVet® readings correlated well with manometric IOP (slope = 0.972, r(2) coefficient = 0.955). No significant differences were observed when comparing eyes or operators; however there was a non-significant trend for TonoVet® readings taken in right eyes to be closer to manometric IOP than those taken in left eyes. The TonoVet® had a non-significant tendency to underestimate manometric IOP. TonoVet® readings obtained during the decremental phase of the experiment were significantly closer (p < 0.004) to manometric IOP than those obtained during the incremental phase. Central corneal thickness significantly increased (p < 0.0001) over the course of the experiment. The TonoVet® rebound tonometer is a reliable and accurate tool for the measurement of IOP in cynomolgus macaques. This tonometer has several advantages, including portability, ease of use, and brief contact with the corneal surface making topical anesthetics unnecessary.
Collapse
Affiliation(s)
- Elizabeth J Elsmo
- Dept. of Ophthalmology & Visual Sciences, University of Wisconsin-Madison, Madison, WI 53792, USA
| | | | | | | |
Collapse
|
36
|
Johnson EC, Doser TA, Cepurna WO, Dyck JA, Jia L, Guo Y, Lambert WS, Morrison JC. Cell proliferation and interleukin-6-type cytokine signaling are implicated by gene expression responses in early optic nerve head injury in rat glaucoma. Invest Ophthalmol Vis Sci 2011; 52:504-18. [PMID: 20847120 DOI: 10.1167/iovs.10-5317] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE In glaucoma, the optic nerve head (ONH) is the principal site of initial axonal injury, and elevated intraocular pressure (IOP) is the predominant risk factor. However, the initial responses of the ONH to elevated IOP are unknown. Here the authors use a rat glaucoma model to characterize ONH gene expression changes associated with early optic nerve injury. METHODS Unilateral IOP elevation was produced in rats by episcleral vein injection of hypertonic saline. ONH mRNA was extracted, and retrobulbar optic nerve cross-sections were graded for axonal degeneration. Gene expression was determined by microarray and quantitative PCR (QPCR) analysis. Significantly altered gene expression was determined by multiclass analysis and ANOVA. DAVID gene ontology determined the functional categories of significantly affected genes. RESULTS The Early Injury group consisted of ONH from eyes with <15% axon degeneration. By array analysis, 877 genes were significantly regulated in this group. The most significant upregulated gene categories were cell cycle, cytoskeleton, and immune system process, whereas the downregulated categories included glucose and lipid metabolism. QPCR confirmed the upregulation of cell cycle-associated genes and leukemia inhibitory factor (Lif) and revealed alterations in expression of other IL-6-type cytokines and Jak-Stat signaling pathway components, including increased expression of IL-6 (1553%). In contrast, astrocytic glial fibrillary acidic protein (Gfap) message levels were unaltered, and other astrocytic markers were significantly downregulated. Microglial activation and vascular-associated gene responses were identified. CONCLUSIONS Cell proliferation and IL-6-type cytokine gene expression, rather than astrocyte hypertrophy, characterize early pressure-induced ONH injury.
Collapse
Affiliation(s)
- Elaine C Johnson
- Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, Portland, Oregon 97201, USA.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Aqueous humor dynamics in inbred rhesus monkeys with naturally occurring ocular hypertension. Exp Eye Res 2010; 91:860-5. [DOI: 10.1016/j.exer.2010.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 08/31/2010] [Accepted: 09/14/2010] [Indexed: 11/24/2022]
|
38
|
Ren L, Danias J. A Role for Complement in Glaucoma? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 703:95-104. [DOI: 10.1007/978-1-4419-5635-4_7] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
39
|
Abstract
PURPOSE To survey the literature to determine how the dimensions of the neuroretinal rim are commonly described, and to clarify and standardize the description of changes in the dimensions of the neuroretinal rim in glaucoma. MATERIALS AND METHODS Literature review of 275 articles describing the neuroretinal rim in glaucoma and a survey of ophthalmologists describing 2 disc photographs. Frequencies of descriptors of the neuroretinal rim were surveyed, which included "thinning" and "narrowing." RESULTS Of the 275 articles, 80 described the neuroretinal rim clinically. Forty-one articles used "thinning" to describe progressive loss of rim tissue in a radial axis, 13 articles used "narrowing" and rest used "width" to describe the characteristics of neuroretinal rim. Of the 295 ophthalmologists, 264 used "thinner," whereas 31 used "narrower" to describe the neuroretinal rim. CONCLUSIONS Accurate phenotyping is an essential part of patient care, research, and training. "Thinning" is currently used more commonly than "narrowing" in the literature to describe progressive loss of the neuroretinal rim in a radial axis. It would be appropriate to use "narrowing" for radial loss or decrease in width and "thinning" for decrease in the thickness of the rim.
Collapse
|
40
|
[Effectiveness and relevance of laser trabeculoplasty: treatment of open-angle glaucoma]. Ophthalmologe 2009; 107:18-21. [PMID: 19844721 DOI: 10.1007/s00347-009-2053-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Laser trabeculoplasty is a common glaucoma therapy that is safe and effective for reducing intraocular pressure. It was developed as a treatment for open-angle glaucoma in the 1970s, and larger studies proved its effectiveness in the years that followed. In recent years, through the implementation of newer processes such as selective laser trabeculoplasty, laser trabeculoplasty has experienced further developments. Because it causes less damage to the trabecular meshwork, it should have fewer adverse effects, making it a repeatable treatment. Studies on the indications, contraindications, and effectiveness of this method in lowering intraocular pressure are reviewed.
Collapse
|
41
|
Fu CT, Sretavan D. Laser-induced ocular hypertension in albino CD-1 mice. Invest Ophthalmol Vis Sci 2009; 51:980-90. [PMID: 19815738 DOI: 10.1167/iovs.09-4324] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To establish a laser-induced model of ocular hypertension (LIOH) in albino CD-1 mice and to characterize the sequence of pathologic events triggered by intraocular pressure (IOP) elevation. METHODS LIOH was induced unilaterally in CD-1 mice by laser photocoagulation of limbal and episcleral veins 270 degrees to 300 degrees circumferentially, sparing the nasal aspect and the long ciliary arteries. IOP was measured with a rebound tonometer. Hematoxylin and eosin-stained plastic sections were used for morphometric analysis of retinal layers, and retinal whole-mounts were immunostained with anti-Brn-3b to quantify retinal ganglion cell (RGC) gene expression ion and density. Axonal and myelin morphologies were characterized using appropriate antibodies, and axon counts were obtained from paraphenylenediamine-stained optic nerve sections. RESULTS LIOH resulted in IOP doubling within 4 hours after laser treatment, which returned to normal by 7 days. Axon degenerative changes, reactive plasticity, and aberrant regrowth were detected at the optic nerve head (ONH) as early as 4 days after treatment. By 7 days, axon number was significantly reduced in the myelinated optic nerve, with concurrent signs of myelin degradation. At 14 days, Brn-3b(+) RGC density was reduced, with neuronal loss confined to the RGC layer and no apparent effects on other retinal layers. CONCLUSIONS Laser photocoagulation of limbal and episcleral veins induces transient ocular hypertension in albino CD-1 mice. The ensuing retinal and optic nerve pathologic events recapitulated key features of glaucoma and placed ONH RGC axon responses as an early manifestation of damage. LIOH in albino mice may be useful as a mouse model to examine mechanisms of RGC and axon glaucomatous injury.
Collapse
Affiliation(s)
- Christine T Fu
- Neuroscience Graduate Program, Department of Ophthalmology, University of California, San Francisco, San Francisco, California 94143, USA.
| | | |
Collapse
|
42
|
Grozdanic SD, Kecova H, Harper MM, Nilaweera W, Kuehn MH, Kardon RH. Functional and structural changes in a canine model of hereditary primary angle-closure glaucoma. Invest Ophthalmol Vis Sci 2009; 51:255-63. [PMID: 19661222 DOI: 10.1167/iovs.09-4081] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
PURPOSE To characterize functional and structural changes in a canine model of hereditary primary angle-closure glaucoma. METHODS Intraocular pressure (IOP) was evaluated with tonometry in a colony of glaucomatous dogs at 8, 15, 18, 20, and 30 months of age. Retinal function was evaluated using electroretinography (scotopic, photopic, and pattern). Examination of anterior segment structures was performed using gonioscopy and high-frequency ultrasonography (HFU). RESULTS A gradual rise in IOP was observed with an increase in age: 8 months, 14 mm Hg (median value); 15 months, 15.5 mm Hg; 18 months, 17.5 mm Hg; 20 months, 24 mm Hg; 30 months, 36 mm Hg. Provocative testing with mydriatic agents (tropicamide and atropine 1%) caused significant increases in IOP (35% and 50%, respectively). HFU analysis showed complete collapse of iridocorneal angles by 20 months of age. Scotopic and photopic ERG analysis did not reveal significant deficits, but pattern ERG analysis showed significantly reduced amplitudes in glaucomatous dogs (glaucoma, 3.5 +/- 0.4 muV; control, 6.2 +/- 0.3 muV; P = 0.004; Student's t-test). Histologic analysis revealed collapse of the iridocorneal angle, posterior bowing of the lamina cribrosa, swelling and loss of large retinal ganglion cells, increased glial reactivity, and increased thickening of the lamina cribrosa. CONCLUSIONS Canine hereditary angle-closure glaucoma is characterized by a progressive increase in intraocular pressure, loss of optic nerve function, and retinal ganglion cell loss.
Collapse
Affiliation(s)
- Sinisa D Grozdanic
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa 50011, USA.
| | | | | | | | | | | |
Collapse
|
43
|
Barraza RA, Rasmussen CA, Loewen N, Cameron JD, Gabelt BT, Teo WL, Kaufman PL, Poeschla EM. Prolonged transgene expression with lentiviral vectors in the aqueous humor outflow pathway of nonhuman primates. Hum Gene Ther 2009; 20:191-200. [PMID: 19301472 DOI: 10.1089/hum.2008.086] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
We injected lentiviral vectors into the eyes of live nonhuman primates to assess potential for glaucoma gene therapy. Anterior chambers of five cynomolgus monkeys were injected with green fluorescent protein (GFP)-encoding feline immunodeficiency viral vectors. The monkeys were monitored for in vivo transgene expression and clinical parameters. Their eyes were harvested 2-15 months postinjection for tissue analyses. All seven eyes injected with 1.0-2.0 x 10(8) transducing units (TU) showed substantial GFP fluorescence in the trabecular meshwork (TM), which was observable even by goniophotographic monitoring for up to 15 months. Only the lowest dose (0.03 x 10(8) TU) failed to result in TM fluorescence detectable in vivo, and five of the eight vector-injected eyes continued to display substantial GFP expression when enucleated eyes were examined at 2, 7, or 15 months postinjection. Some transduced cells were also detected in the iris and ciliary body. Mild, transient postinjection inflammatory responses exceeding that induced by a control saline injection were observed, but vectors did not raise intraocular pressure and were well tolerated. The results demonstrate the first lentiviral vector transduction of the nonhuman primate aqueous humor outflow pathway and support application of the system to human glaucoma gene therapy.
Collapse
Affiliation(s)
- Román A Barraza
- Department of Molecular Medicine, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Poeschla EM, Barraza RA, Rasmussen C, Loewen N, Cameron JD, Gabelt BT, Teo W, Kaufman PL. Prolonged transgene expression with lentiviral vectors in the aqueous humor outflow pathway of non-human primates. Hum Gene Ther 2008. [DOI: 10.1089/hgt.2008.086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
45
|
Kompass KS, Agapova OA, Li W, Kaufman PL, Rasmussen CA, Hernandez MR. Bioinformatic and statistical analysis of the optic nerve head in a primate model of ocular hypertension. BMC Neurosci 2008; 9:93. [PMID: 18822132 PMCID: PMC2567987 DOI: 10.1186/1471-2202-9-93] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2008] [Accepted: 09/26/2008] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND The nonhuman primate model of glaucomatous optic neuropathy most faithfully reproduces the human disease. We used high-density oligonucleotide arrays to investigate whole genome transcriptional changes occurring at the optic nerve head during primate experimental glaucoma. RESULTS Laser scarification of the trabecular meshwork of cynomolgus macaques produced elevated intraocular pressure that was monitored over time and led to varying degrees of damage in different samples. The macaques were examined clinically before enucleation and the myelinated optic nerves were processed post-mortem to determine the degree of neuronal loss. Global gene expression was examined in dissected optic nerve heads with Affymetrix GeneChip microarrays. We validated a subset of differentially expressed genes using qRT-PCR, immunohistochemistry, and immuno-enriched astrocytes from healthy and glaucomatous human donors. These genes have previously defined roles in axonal outgrowth, immune response, cell motility, neuroprotection, and extracellular matrix remodeling. CONCLUSION Our findings show that glaucoma is associated with increased expression of genes that mediate axonal outgrowth, immune response, cell motility, neuroprotection, and ECM remodeling. These studies also reveal that, as glaucoma progresses, retinal ganglion cell axons may make a regenerative attempt to restore lost nerve cell contact.
Collapse
Affiliation(s)
- Kenneth S Kompass
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Olga A Agapova
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wenjun Li
- Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA
| | - Paul L Kaufman
- Department of Ophthalmology and Visual Sciences, University of Wisconsin Medical School, Madison, WI 53792, USA
| | - Carol A Rasmussen
- Department of Ophthalmology and Visual Sciences, University of Wisconsin Medical School, Madison, WI 53792, USA
| | - M Rosario Hernandez
- Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA
| |
Collapse
|
46
|
Abstract
Elevated intraocular pressure in glaucoma can injure retinal ganglion cells and trigger the spread of disease to connected target vision structures of the brain. Glaucomatous degeneration has been observed in retrobulbar and intracranial optic nerve, lateral geniculate nucleus, and visual cortex of the brain. Oxidative damage and glutamate toxicity are implicated in transsynaptic central nervous system injury in glaucoma, similar to other neurodegenerative diseases. The perception of glaucoma as a disorder of "visual neurons" within the eye and brain may contribute to understanding progressive disease, and encourage comprehensive treatment strategies to prevent vision loss in glaucoma.
Collapse
|
47
|
|
48
|
|
49
|
Author reply. Ophthalmology 2007. [DOI: 10.1016/j.ophtha.2006.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
50
|
Heinrich SP. A primer on motion visual evoked potentials. Doc Ophthalmol 2007; 114:83-105. [PMID: 17431818 DOI: 10.1007/s10633-006-9043-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 11/28/2006] [Indexed: 12/18/2022]
Abstract
Motion visual evoked potentials (motion VEPs) have been used since the late 1960s to investigate the properties of human visual motion processing, and continue to be a popular tool with a possible future in clinical diagnosis. This review first provides a synopsis of the characteristics of motion VEPs and then summarizes important methodological aspects. A subsequent overview illustrates how motion VEPs have been applied to study basic functions of human motion processing and shows perspectives for their use as a diagnostic tool.
Collapse
Affiliation(s)
- Sven P Heinrich
- Sektion Funktionelle Sehforschung, Universitäts-Augenklinik, Freiburg, Germany.
| |
Collapse
|