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Boodram V, Lim H. Protective effects of nicotinamide in a mouse model of glaucoma DBA/2 studied by second-harmonic generation microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.07.583928. [PMID: 38496666 PMCID: PMC10942456 DOI: 10.1101/2024.03.07.583928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Glaucoma is a blinding disease where the retinal ganglion cells and their axons degenerate. Degradation of axonal microtubules is thought to play a critical role in the pathogenesis, but the mechanism is unknown. Here we investigate whether microtubule disruption in glaucoma can be alleviated by metabolic rescue. The morphology and integrity of microtubules of the retinal nerve fibers were evaluated by second-harmonic generation microscopy in a mouse model of glaucoma, DBA/2, which received a dietary supplement of nicotinamide to reduce metabolic stress. It was compared with control DBA/2, which did not receive nicotinamide, and non-glaucomatous DBA/2-Gpnmb+. We found that morphology but not microtubules are significantly protected by nicotinamide. Furthermore, from co-registered images of second-harmonic generation and immunofluorescence, it was determined that microtubule deficit was not due to a shortage of tubulins. Microtubule deficit colocalized with the sectors in which the retinal ganglion cells were disconnected from the brain, indicating that microtubule disruption is associated with axonal transport deficit in glaucoma. Together, our data suggests significant role axonal microtubules play in glaucomatous degeneration, offering a new opportunity for neuroprotection.
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Affiliation(s)
- Vinessia Boodram
- Department of Physics and Astronomy, Hunter College of the City University of New York, New York, NY 10065
| | - Hyungsik Lim
- Department of Physics and Astronomy, Hunter College of the City University of New York, New York, NY 10065
- School of Optometry, Indiana University, Bloomington, IN 47405
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2
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Nishinaka A, Tanaka M, Aoshima K, Kuriyama A, Sasaki T, Otsu W, Yasuda H, Nakamura S, Shimazawa M, Hara H. The pathological association between the anterior eye segment and the retina in a murine model of neovascular glaucoma. FASEB J 2022; 36:e22323. [PMID: 35485981 DOI: 10.1096/fj.202101917r] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/30/2022] [Accepted: 04/07/2022] [Indexed: 11/11/2022]
Abstract
Neovascular glaucoma (NVG) is caused by the formation of new blood vessels in the angle, iris, and cornea in retinal ischemic disease, such as proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), which can reduce the visual acuity. However, the pathophysiological symptoms of NVG are still not well understood because there is no model for the formation of NVG in the angle, iris, and cornea. The aim of this study was to investigate the involvement of NVG during ischemic disease, in a murine model of retinal ischemia. We evaluated the changes of the intraocular pressure (IOP) and pathological symptoms in the anterior eye segment and retina in this model, and the changes in the RNA or protein expression of vascular endothelial growth factor (VEGF) and fibrosis-related factors were analyzed in the retina and cornea by quantitative real-time polymerase chain reaction or western blot, respectively. Furthermore, we examined the changes in IOP after intravitreal injection of an anti-VEGF antibody. First, NVG formed in the retinal ischemic murine model, and the IOP was elevated in mice with NVG formation. Interestingly, VEGF expression was decreased in the retina but increased in the cornea in the murine model of NVG. On the other hand, fibrosis-related factors were increased in the retina and also significantly increased in the cornea in NVG. Moreover, the administration of anti-VEGF antibody immediately after vessel occlusion suppressed the increase in IOP, but administration at 7 days after vessel occlusion accelerated the increase in IOP. These findings suggest that the formation of NVG may be correlated with the pathological symptoms of retinal ischemic disease, via changes in VEGF and fibrosis-related factor expression.
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Affiliation(s)
- Anri Nishinaka
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Miruto Tanaka
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Kota Aoshima
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Aika Kuriyama
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Takahiro Sasaki
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Wataru Otsu
- Department of Biomedical Research Laboratory, Gifu Pharmaceutical University, Gifu, Japan
| | - Hiroto Yasuda
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Shinsuke Nakamura
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Masamitsu Shimazawa
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan.,Department of Biomedical Research Laboratory, Gifu Pharmaceutical University, Gifu, Japan
| | - Hideaki Hara
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
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3
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Muir ER, Chandra SB, Narayanan D, Zhang V, Zhang I, Jiang Z, Kiel JW, Duong TQ. Effects of chronic mild hyperoxia on retinal and choroidal blood flow and retinal function in the DBA/2J mouse model of glaucoma. PLoS One 2022; 17:e0266192. [PMID: 35333901 PMCID: PMC8956188 DOI: 10.1371/journal.pone.0266192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 03/15/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose To test the hypothesis that mild chronic hyperoxia treatment would improve retinal function despite a progressive decline in ocular blood flow in the DBA/2J mouse model of glaucoma. Materials and methods DBA/2J mice were treated with chronic mild hyperoxia (30% O2) beginning at 4.5 months of age or were untreated by giving normal room air. Retinal and choroidal blood flow (RBF and ChBF, respectively) were measured at 4, 6, and 9 months of age by MRI. Blood flow was additionally measured under hypercapnia challenge (5% CO2 inhalation) to assess vascular reactivity. Intraocular pressure (IOP) was measured using a rebound tonometer at the same time points. Scotopic flash electroretinograms (ERGs) were recorded at 9 months of age. Results Both ChBF and RBF were reduced and significantly affected by age (p < 0.01), but neither were significantly affected by O2-treatment (p > 0.05). ChBF significantly increased in response to hypercapnia (p < 0.01), which was also unaffected by O2-treatment. Significant effects of age (p < 0.001) and of the interaction of age with treatment (p = 0.028) were found on IOP. IOP significantly decreased in O2-treated mice at 6 months compared to 4 months of age (p < 0.001), while IOP trended to increase with age in untreated mice. The amplitude of the b-wave from ERG was significantly increased in O2-treated DBA/2J compared to the untreated mice (p = 0.012), while the a-wave and oscillatory potentials were not significantly affected (p > 0.05). Conclusion This study investigated the effects of chronic mild hyperoxia on retinal function and on retinal and choroidal blood flow in a mouse model of glaucoma. Retinal function was improved in the O2-treated mice at late stage, despite a progressive decline of RBF and ChBF with age that was comparable to untreated mice.
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Affiliation(s)
- Eric R. Muir
- Department of Radiology, Stony Brook University, Stony Brook, NY, United States of America
- * E-mail:
| | - Saurav B. Chandra
- Research Imaging Institute, University of Texas Health San Antonio, San Antonio, TX, United States of America
| | - Divya Narayanan
- Department of Ophthalmology, University of Texas Health San Antonio, San Antonio, TX, United States of America
| | - Vincent Zhang
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, United States of America
| | - Ike Zhang
- Department of Radiology, Stony Brook University, Stony Brook, NY, United States of America
| | - Zhao Jiang
- Department of Radiology, Stony Brook University, Stony Brook, NY, United States of America
| | - Jeffrey W. Kiel
- Department of Ophthalmology, University of Texas Health San Antonio, San Antonio, TX, United States of America
| | - Timothy Q. Duong
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, United States of America
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4
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Safety, efficacy and delivery of multiple nucleoside analogs via drug encapsulated carbon (DECON) based sustained drug release platform. Eur J Pharm Biopharm 2022; 173:150-159. [PMID: 35314347 PMCID: PMC9113733 DOI: 10.1016/j.ejpb.2022.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/22/2022] [Accepted: 03/04/2022] [Indexed: 11/24/2022]
Abstract
Acyclovir and similar nucleoside analogs form an essential frontline treatment for various herpesvirus infections of the eye. However, these drugs have low ocular retention when delivered topically and need to be administered several times every day. We have previously demonstrated that acyclovir loaded into activated carbon can be used to significantly decrease dosage frequency in a murine model of ocular infection. In this study, we demonstrate that other nucleoside analogs such as ganciclovir, penciclovir and famciclovir have excellent loading and release profile similar to acyclovir. Similarly we also demonstrate that nucleoside analog loaded carbons termed DECON are effective at very low concentrations in treating active viral infection of human corneal epithelial cells. In this study, using a variety of techniques to evaluate corneal dryness, nerve sensitivity, intraocular pressure, corneal thickness, and somatic inflammation, we report that DECON is well tolerated after administration three times daily over the course of four weeks.
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Rohowetz LJ, Mardelli ME, Duncan RS, Riordan SM, Koulen P. The Contribution of Anterior Segment Abnormalities to Changes in Intraocular Pressure in the DBA/2J Mouse Model of Glaucoma: DBA/2J-Gpnmb+/SjJ Mice as Critical Controls. Front Neurosci 2022; 15:801184. [PMID: 35185449 PMCID: PMC8850401 DOI: 10.3389/fnins.2021.801184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 12/29/2021] [Indexed: 11/13/2022] Open
Abstract
The contributions of anterior segment abnormalities to the development of ocular hypertension was determined in the DBA/2J mouse model of glaucoma. Intraocular pressure (IOP) was measured non-invasively. Iris pigment dispersion (IPD) and corneal calcification were measured weekly starting at 20 weeks of age in DBA/2J and DBA/2J-Gpnmb+/SjJ mice. Thickness, surface area, auto-fluorescence intensity, and perimeter length of calcified regions were measured in postmortem corneas using confocal microscopy. DBA/2J mice developed elevated IOP between 9 and 12 months of age, but DBA/2J-Gpnmb+/SjJ mice did not. Corneal calcification was found at all ages observed and at similar frequencies in both strains with 83.3% of DBA/2J eyes and 60.0% of DBA/2J-Gpnmb+/SjJ eyes affected at 12 months (P = 0.11). Calcification increased with age in both DBA/2J (P = 0.049) and DBA/2J-Gpnmb+/SjJ mice (P = 0.04) when assessed qualitatively and based on mixed-effects analysis. No differences in the four objective measures of calcification were observed between strains or ages. At 12 months of age, DBA/2J mice with corneal calcification had greater mean IOP than DBA/2J mice without corneal calcification. IOP was not correlated with the qualitatively assessed measures of calcification. For the subset of eyes with ocular hypertension, which were only found in DBA/2J mice, IOP was negatively correlated with the qualitative degree of calcification, but was not correlated with the four quantitative measures of calcification. Differences in IOP were not observed between DBA/2J-Gpnmb+/SjJ mice with and without calcification at any age. IPD increased with age and demonstrated a moderate correlation with IOP in DBA/2J mice, but was not observed in DBA/2J-Gpnmb+/SjJ mice. In the DBA/2J mouse model of glaucoma, increased IPD is positively correlated with an increase in IOP and corneal calcification is present in the majority of eyes at and after age 9 months. However, while IPD causes ocular hypertension, corneal calcification does not appear to contribute to the elevation of IOP, as the control strain DBA/2J-Gpnmb+/SjJ exhibits corneal calcification similar to DBA/2J mice, but does not develop ocular hypertension. Corneal calcification, therefore, does not appear to be a contributing factor to the development of elevated IOP in DBA/2J mice.
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Affiliation(s)
- Landon J. Rohowetz
- Department of Ophthalmology, Vision Research Center, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, United States
| | - Marc E. Mardelli
- Department of Ophthalmology, Vision Research Center, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, United States
| | - R. Scott Duncan
- Department of Ophthalmology, Vision Research Center, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, United States
| | - Sean M. Riordan
- Department of Ophthalmology, Vision Research Center, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, United States
| | - Peter Koulen
- Department of Ophthalmology, Vision Research Center, School of Medicine, University of Missouri – Kansas City, Kansas City, MO, United States
- Department of Biomedical Sciences, School of Medicine, University of Missouri—Kansas City, Kansas City, MO, United States
- *Correspondence: Peter Koulen,
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6
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McDowell CM, Kizhatil K, Elliott MH, Overby DR, van Batenburg-Sherwood J, Millar JC, Kuehn MH, Zode G, Acott TS, Anderson MG, Bhattacharya SK, Bertrand JA, Borras T, Bovenkamp DE, Cheng L, Danias J, De Ieso ML, Du Y, Faralli JA, Fuchshofer R, Ganapathy PS, Gong H, Herberg S, Hernandez H, Humphries P, John SWM, Kaufman PL, Keller KE, Kelley MJ, Kelly RA, Krizaj D, Kumar A, Leonard BC, Lieberman RL, Liton P, Liu Y, Liu KC, Lopez NN, Mao W, Mavlyutov T, McDonnell F, McLellan GJ, Mzyk P, Nartey A, Pasquale LR, Patel GC, Pattabiraman PP, Peters DM, Raghunathan V, Rao PV, Rayana N, Raychaudhuri U, Reina-Torres E, Ren R, Rhee D, Chowdhury UR, Samples JR, Samples EG, Sharif N, Schuman JS, Sheffield VC, Stevenson CH, Soundararajan A, Subramanian P, Sugali CK, Sun Y, Toris CB, Torrejon KY, Vahabikashi A, Vranka JA, Wang T, Willoughby CE, Xin C, Yun H, Zhang HF, Fautsch MP, Tamm ER, Clark AF, Ethier CR, Stamer WD. Consensus Recommendation for Mouse Models of Ocular Hypertension to Study Aqueous Humor Outflow and Its Mechanisms. Invest Ophthalmol Vis Sci 2022; 63:12. [PMID: 35129590 PMCID: PMC8842499 DOI: 10.1167/iovs.63.2.12] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 12/08/2021] [Indexed: 01/07/2023] Open
Abstract
Due to their similarities in anatomy, physiology, and pharmacology to humans, mice are a valuable model system to study the generation and mechanisms modulating conventional outflow resistance and thus intraocular pressure. In addition, mouse models are critical for understanding the complex nature of conventional outflow homeostasis and dysfunction that results in ocular hypertension. In this review, we describe a set of minimum acceptable standards for developing, characterizing, and utilizing mouse models of open-angle ocular hypertension. We expect that this set of standard practices will increase scientific rigor when using mouse models and will better enable researchers to replicate and build upon previous findings.
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Affiliation(s)
- Colleen M. McDowell
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | | | - Michael H. Elliott
- University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States
| | - Darryl R. Overby
- Department of Bioengineering, Imperial College London, United Kingdom
| | | | - J. Cameron Millar
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Markus H. Kuehn
- Department of Ophthalmology and Visual Sciences and Institute for Vision Research, The University of Iowa; Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Medical Center, Iowa City, Iowa, United States
| | - Gulab Zode
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Ted S. Acott
- Ophthalmology and Biochemistry and Molecular Biology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Michael G. Anderson
- Department of Molecular Physiology and Biophysics and Department of Ophthalmology and Visual Sciences, The University of Iowa; Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Medical Center, Iowa City, Iowa, United States
| | | | - Jacques A. Bertrand
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Terete Borras
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
| | | | - Lin Cheng
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - John Danias
- SUNY Downstate Health Sciences University, Brooklyn, New York, United States
| | - Michael Lucio De Ieso
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, North Carolina, United States
| | - Yiqin Du
- Department of Ophthalmology, University of Pittsburgh, Pennsylvania, United States
| | - Jennifer A. Faralli
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University of Regensburg, Regensburg, Germany
| | - Preethi S. Ganapathy
- Department of Ophthalmology and Visual Sciences, SUNY Upstate Medical University, Syracuse, New York, United States
| | - Haiyan Gong
- Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Samuel Herberg
- Department of Ophthalmology and Visual Sciences, SUNY Upstate Medical University, Syracuse, New York, United States
| | | | - Peter Humphries
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - Simon W. M. John
- Department of Ophthalmology, Columbia University, New York, New York, United States
| | - Paul L. Kaufman
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Kate E. Keller
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Mary J. Kelley
- Department of Ophthalmology and Department of Integrative Biosciences, Oregon Health & Science University, Portland, Oregon, United States
| | - Ruth A. Kelly
- Ocular Genetics Unit, Smurfit Institute of Genetics, Trinity College Dublin, Dublin, Ireland
| | - David Krizaj
- Department of Ophthalmology, University of Utah School of Medicine, Salt Lake City, Utah, United States
| | - Ajay Kumar
- Department of Ophthalmology, University of Pittsburgh, Pennsylvania, United States
| | - Brian C. Leonard
- Department of Surgical and Radiological Sciences, University of California, Davis, Davis, California, United States
| | - Raquel L. Lieberman
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, United States
| | - Paloma Liton
- Department of Ophthalmology and Department of Pathology, Duke University, Durham, North Carolina, United States
| | - Yutao Liu
- Department of Cellular Biology and Anatomy, James & Jean Culver Vision Discovery Institute, Augusta University, Augusta, Georgia, United States
| | - Katy C. Liu
- Duke Eye Center, Duke Health, Durham, North Carolina, United States
| | - Navita N. Lopez
- Department of Neurobiology, University of Utah, Salt Lake City, Utah, United States
| | - Weiming Mao
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Timur Mavlyutov
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Fiona McDonnell
- Duke Eye Center, Duke Health, Durham, North Carolina, United States
| | - Gillian J. McLellan
- Department of Surgical Sciences and Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Philip Mzyk
- Department of Ophthalmology and Visual Sciences, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | - Andrews Nartey
- College of Optometry, University of Houston, Houston, Texas, United States
| | - Louis R. Pasquale
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, New York, United States
| | - Gaurang C. Patel
- Ophthalmology Research, Regeneron Pharmaceuticals, Tarreytown, New York, United States
| | | | - Donna M. Peters
- Department of Pathology and Laboratory Medicine, University of Wisconsin–Madison, Madison, Wisconsin, United States
| | | | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Naga Rayana
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Urmimala Raychaudhuri
- Department of Neurobiology, University of California, Irvine, Irvine, California, United States
| | - Ester Reina-Torres
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Ruiyi Ren
- Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Douglas Rhee
- Case Western Reserve University School of Medicine, Cleveland, Ohio, United States
| | - Uttio Roy Chowdhury
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States
| | - John R. Samples
- Washington State University, Floyd Elson College of Medicine, Spokane, Washington, United States
| | | | - Najam Sharif
- Santen Inc., Emeryville, California, United States
| | - Joel S. Schuman
- Department of Ophthalmology and Department of Physiology and Neuroscience, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States; Departments of Biomedical Engineering and Electrical and Computer Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States; Center for Neural Science, College of Arts and Science, New York University, New York, New York, United States
| | - Val C. Sheffield
- Department of Pediatrics and Department of Ophthalmology and Visual Sciences, University of Iowa Carver College of Medicine, Iowa City, Iowa, United States
| | - Cooper H. Stevenson
- Department of Pharmacology & Neuroscience, and North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Avinash Soundararajan
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | | | - Chenna Kesavulu Sugali
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Yang Sun
- Veterans Affairs Palo Alto Health Care System, Stanford University, Palo Alto, California, United States
| | - Carol B. Toris
- Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, Nebraska, United States; Department of Ophthalmology and Vision Sciences, The Ohio State University, Columbus, Ohio, United States
| | | | - Amir Vahabikashi
- Cell and Developmental Biology Department, Northwestern University, Chicago, Illinois, United States
| | - Janice A. Vranka
- Department of Ophthalmology, Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Ting Wang
- Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, Indiana, United States
| | - Colin E. Willoughby
- Genomic Medicine, Biomedical Sciences Research Institute, Ulster University, Coleraine, Northern Ireland, United Kingdom
| | - Chen Xin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Hongmin Yun
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Hao F. Zhang
- Biomedical Engineering Department, Northwestern University, Evanston, Illinois, United States
| | - Michael P. Fautsch
- Biomedical Engineering Department, Northwestern University, Evanston, Illinois, United States
| | | | - Abbot F. Clark
- Department of Pharmacology and Neuroscience, North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - C. Ross Ethier
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology; Emory University School of Medicine, Emory University, Atlanta, Georgia, United States
| | - W. Daniel Stamer
- Duke Ophthalmology, Duke University, Durham, North Carolina, United States
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7
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Bertens CJF, van Mechelen RJS, Berendschot TTJM, Gijs M, Wolters JEJ, Gorgels TGMF, Nuijts RMMA, Beckers HJM. Repeatability, reproducibility, and agreement of three tonometers for measuring intraocular pressure in rabbits. Sci Rep 2021; 11:19217. [PMID: 34584185 PMCID: PMC8478901 DOI: 10.1038/s41598-021-98762-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 09/14/2021] [Indexed: 12/04/2022] Open
Abstract
The aim of this study was to evaluate repeatability, reproducibility, and agreement of three commonly used tonometers in animal research (TonoLab, TonoVet, and TonoPEN AVIA) in a cohort of 24 rabbits. Additionally, the impact of sedation on IOP was investigated in 21 New Zealand White rabbits with the TonoVet tonometer. Repeatability was determined using the coefficient of variation (CoV) for two observers. For the TonoLab (6.55%) and TonoVet (6.38%) the CoV was lower than for the TonoPEN AVIA (10.88%). The reproducibility was highest for the TonoVet (0.2 ± 3.3 mmHg), followed by the TonoLab (0 ± 12.89 mmHg) and lowest for the TonoPEN AVIA (− 1.48 ± 10.3 mmHg). The TonoLab and TonoVet showed the highest agreement (r = 0.85, R2 = 0.73). After sedation, a significant IOP reduction (often > 25%) was observed. Our results show that among the three tonometers tested, the TonoVet tonometer is best for use in rabbits while the TonoLab should be avoided. The impact of sedation on IOP was substantial and should be taken into account during experimentation.
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Affiliation(s)
- Christian J F Bertens
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands. .,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands.
| | - Ralph J S van Mechelen
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
| | - Tos T J M Berendschot
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands
| | - Marlies Gijs
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
| | - Jarno E J Wolters
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
| | - Theo G M F Gorgels
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
| | - Rudy M M A Nuijts
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
| | - Henny J M Beckers
- Department of Ophthalmology, University Eye Clinic Maastricht, School for Mental Health and Neuroscience (MHeNs), Maastricht University Medical Center+ (MUMC+), P. Debyelaan 25, PO Box 5800, 6229 HX, Maastricht, The Netherlands.,Chemelot Institute for Science and Technology (InSciTe), Gaetano Martinolaan 63-65, 6229 GS, Maastricht, The Netherlands
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8
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Szabo E, Patko E, Vaczy A, Molitor D, Csutak A, Toth G, Reglodi D, Atlasz T. Retinoprotective Effects of PACAP Eye Drops in Microbead-Induced Glaucoma Model in Rats. Int J Mol Sci 2021; 22:8825. [PMID: 34445531 PMCID: PMC8396165 DOI: 10.3390/ijms22168825] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 08/09/2021] [Accepted: 08/13/2021] [Indexed: 01/29/2023] Open
Abstract
Glaucoma is associated with increased intraocular pressure (IOP), causing the apoptosis of retinal ganglion cells (RGCs) and the loss of their axons leading to blindness. Pituitary adenylate cyclase activating polypeptide (PACAP) is neuroprotective in several neural injuries, including retinopathies. The aim of this study was to investigate the effects of PACAP1-38 eye drops in a model of glaucoma. IOP was elevated bilaterally by injections of microbeads to block the aqueous humor outflow. The control groups received the same volume of saline. Animals were treated with PACAP1-38 (1 µg/drop, 3 × 1 drop/day) or vehicle for 4 weeks starting one day after the injections. Retinal morphology by histology and optical coherence tomography, function by electroretinography, and IOP changes were analyzed. Animals were sacrificed 8 weeks after the injections. Microbeads injections induced a significant increase in the IOP, while PACAP1-38 treatment lowered it to normal levels (~10 mmHg). Significant retinal degeneration and functional impairment were observed in the microbead-injected group without PACAP1-38 treatment. In the microbeads + PACAP1-38 group, the retinal morphology and functionality were close to the normal values. In summary, our results show that PACAP1-38, given in form of eye drops, is neuroprotective in glaucoma, providing the basis for potential future therapeutic administration.
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Affiliation(s)
- Edina Szabo
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
| | - Evelin Patko
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
| | - Alexandra Vaczy
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
| | - Dorottya Molitor
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
| | - Adrienne Csutak
- Department of Ophthalmology, Clinical Centre, University of Pecs Medical School, 7632 Pecs, Hungary;
| | - Gabor Toth
- Department of Medical Chemistry, Faculty of Medicine, University of Szeged, 6720 Szeged, Hungary;
| | - Dora Reglodi
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
- Szentagothai Research Center, University of Pecs, 7624 Pecs, Hungary
| | - Tamas Atlasz
- Department of Anatomy, MTA-PTE PACAP Research Team, University of Pecs Medical School, 7624 Pecs, Hungary; (E.S.); (E.P.); (A.V.); (D.M.); (D.R.)
- Szentagothai Research Center, University of Pecs, 7624 Pecs, Hungary
- Department of Sportbiology, University of Pecs, 7624 Pecs, Hungary
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9
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Tao X, Sabharwal J, Wu SM, Frankfort BJ. Intraocular Pressure Elevation Compromises Retinal Ganglion Cell Light Adaptation. Invest Ophthalmol Vis Sci 2021; 61:15. [PMID: 33064129 PMCID: PMC7571289 DOI: 10.1167/iovs.61.12.15] [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: 01/10/2023] Open
Abstract
Purpose Functional adaptation to ambient light is a key characteristic of retinal ganglion cells (RGCs), but little is known about how adaptation is affected by factors that are harmful to RGC health. We explored adaptation-induced changes to RGC physiology when exposed to increased intraocular pressure (IOP), a major risk factor for glaucoma. Methods Wild-type mice of both sexes were subjected to 2 weeks of IOP elevation using the bead model. Retinas were assessed using a multielectrode array to record RGC responses to checkerboard white noise stimulation under both scotopic and photopic light levels. This information was used to calculate a spike-triggered average (STA) for each RGC with which to compare between lighting levels. Results Low but not high IOP elevation resulted in several distinct RGC functional changes: (1) diminished adaptation-dependent receptive field (RF) center-surround interactions; (2) increased likelihood of a scotopic STA; and (3) increased spontaneous firing rate. Center RF size change with lighting level varied among RGCs, and both the center and surround STA peak times were consistently increased under scotopic illumination, although none of these properties were impacted by IOP level. Conclusions These findings provide novel evidence that RGCs exhibit reduced light-dependent adaptation and increased excitability when IOP is elevated to low but not high levels. These results may reveal functional changes that occur early in glaucoma, which can potentially be used to identify patients with glaucoma at earlier stages when intervention is most beneficial.
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Affiliation(s)
- Xiaofeng Tao
- Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, United States
| | - Jasdeep Sabharwal
- Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States
| | - Samuel M Wu
- Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States
| | - Benjamin J Frankfort
- Department of Ophthalmology, Baylor College of Medicine, Houston, Texas, United States.,Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States
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10
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Fiedorowicz M, Wełniak-Kamińska M, Świątkiewicz M, Orzeł J, Chorągiewicz T, Toro MD, Rejdak R, Bogorodzki P, Grieb P. Changes of Ocular Dimensions as a Marker of Disease Progression in a Murine Model of Pigmentary Glaucoma. Front Pharmacol 2020; 11:573238. [PMID: 33013417 PMCID: PMC7500411 DOI: 10.3389/fphar.2020.573238] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/17/2020] [Indexed: 12/11/2022] Open
Abstract
Purpose The elevation of intraocular pressure (IOP), a major risk factor in glaucoma, is an important parameter tracked in experimental models of this disease. However, IOP measurement in laboratory rodents is challenging and may not correlate with some key pathological events that occur in the development of glaucoma. The aims of this study were to quantify changes in ocular morphology in DBA/2J mice that develop spontaneous, age-dependent, pigmentary glaucoma and to check the possible correlation of these parameters with IOP. Method Eye morphology was evaluated with MRI in DBA/2J, DBA/2J-Gpnmb+/SjJ, and C57BL/6J female mice ages 3, 6, 9, 12, and 15 months. The animals were anesthetized with isoflurane. A planar receive-only surface coil (inner diameter = 10 mm) was placed over each animal’s left eye and the image was acquired with a 7T small animal-dedicated magnetic resonance tomograph and T2-weighted TurboRARE sequence. Ocular dimensions were manually quantitated using OsiriX software. IOP was measured with rebound tonometry. Results In the control animals, no age-related changes in the ocular morphology were noted. Since 6 months of age, the anterior chamber deepening and elongation of the eyeballs of DBA/2J mice was detectable. We found a significant, positive correlation between IOP and axial length, anterior chamber area, or anterior chamber width in C57BL/6J mice but not in DBA/2J mice. However, after excluding the measurements performed in the oldest DBA/2J mice (i.e. analyzing only the animals ages 3 to 12 months), we demonstrated a significant positive correlation between IOP and anterior chamber width. Conclusion High-resolution magnetic resonance imaging of the eye area in mice enables reproducible and consistent measures of key dimensions of the eyeball. We observed age-dependent alterations in the eye morphology of DBA/2J mice that mostly affected the anterior chamber. We also demonstrated a correlation between some of the ocular dimensions and the IOP of C57Bl/6J mice and DBA/2J mice with moderately advanced glaucomatous pathology.
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Affiliation(s)
- Michał Fiedorowicz
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.,Small Animal Magnetic Resonance Imaging Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Marlena Wełniak-Kamińska
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.,Small Animal Magnetic Resonance Imaging Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Maciej Świątkiewicz
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.,Small Animal Magnetic Resonance Imaging Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Jarosław Orzeł
- Small Animal Magnetic Resonance Imaging Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.,Faculty of Electronics and Information Technology, Warsaw University of Technology, Warsaw, Poland
| | - Tomasz Chorągiewicz
- Department of General Ophthalmology, Medical University of Lublin, Lublin, Poland
| | - Mario Damiano Toro
- Department of General Ophthalmology, Medical University of Lublin, Lublin, Poland.,Faculty of Medical Sciences, Collegium Medicum, Cardinal Stefan Wyszyński University, Warsaw, Poland
| | - Robert Rejdak
- Department of General Ophthalmology, Medical University of Lublin, Lublin, Poland
| | - Piotr Bogorodzki
- Small Animal Magnetic Resonance Imaging Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.,Faculty of Electronics and Information Technology, Warsaw University of Technology, Warsaw, Poland
| | - Paweł Grieb
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
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11
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Faralli JA, Filla MS, McDowell CM, Peters DM. Disruption of fibronectin fibrillogenesis affects intraocular pressure (IOP) in BALB/cJ mice. PLoS One 2020; 15:e0237932. [PMID: 32822410 PMCID: PMC7444551 DOI: 10.1371/journal.pone.0237932] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 08/05/2020] [Indexed: 12/31/2022] Open
Abstract
Increased deposition of fibronectin fibrils containing EDA+fibronectin by TGFβ2 is thought to be involved in the reduction of aqueous humor outflow across the trabecular meshwork (TM) of the eye and the elevation in intraocular pressure (IOP) observed in primary open angle glaucoma (POAG). Using a fibronectin-binding peptide called FUD that can disrupt fibronectin fibrillogenesis, we examined if disrupting fibronectin fibrillogenesis would affect IOP in the TGFβ2 BALB/cJ mouse model of ocular hypertension. BALB/cJ mice that had been intravitreally injected with an adenovirus (Ad5) expressing a bioactive TGFβ2226/228 showed a significant increase in IOP after 2 weeks. When 1μM FUD was injected intracamerally into mice 2 weeks post Ad5-TGFβ2 injection, FUD significantly reduced IOP after 2 days. Neither mutated FUD (mFUD) nor PBS had any effect on IOP. Four days after FUD was injected, IOP returned to pre-FUD injection levels. In the absence of TGFβ2, intracameral injection of FUD had no effect on IOP. Western blotting of mouse anterior segments expressing TGFβ2 showed that FUD decreased fibronectin levels 2 days after intracameral injection (p<0.05) but not 7 days compared to eyes injected with PBS. mFUD injection had no significant effect on fibronectin levels at any time point. Immunofluorescence microscopy studies in human TM (HTM) cells showed that treatment with 2ng/ml TGFβ2 increased the amount of EDA+ and EDB+ fibronectin incorporated into fibrils and 2μM FUD decreased both EDA+ and EDB+ fibronectin in fibrils. An on-cell western assay validated this and showed that FUD caused a 67% reduction in deoxycholate insoluble fibronectin fibrils in the presence of TGFβ2. FUD also caused a 43% reduction in fibronectin fibrillogenesis in the absence of TGFβ2 while mFUD had no effect. These studies suggest that targeting the assembly of fibronectin fibrillogenesis may represent a way to control IOP.
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Affiliation(s)
- Jennifer A. Faralli
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Mark S. Filla
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Colleen M. McDowell
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Donna M. Peters
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, United States of America
- * E-mail:
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12
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Peripheral Latanoprost Administration Lowers Intraocular Pressure in the Wistar Rat. Ophthalmol Ther 2020; 9:1-8. [PMID: 32383108 PMCID: PMC7406633 DOI: 10.1007/s40123-020-00256-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Indexed: 01/20/2023] Open
Abstract
Purpose Instillation of latanoprost eye drops into the conjunctival sac to lower
intraocular pressure (IOP) is the most frequently used treatment for primary
open-angle glaucoma. The aim of this study was to evaluate the influence of
latanoprost on IOP in the rat when applied peripherally. Methods A rodent-dedicated tonometer was used to measure IOP in conscious adult
male normotensive Wistar rats habituated to the measurement procedure. Commercially
available 0.005% latanoprost solutions were continuously delivered to the periphery
of the eye over 7 days using mini-pumps inserted subcutaneously in the animal’s back,
and IOP was measured daily. For comparison, a solution containing an equimolar
concentration of latanoprost acid, an active compound of latanoprost, was similarly
infused into the eyes of different Wistar rats. Results Continuous subcutaneous infusion of latanoprost gradually decreased the
IOP; the stable nadir of IOP, which was 20% lower than that prior to the start of
infusion, was reached on day 3. The effect was statistically significant and fully
reversed 2 days after cessation of drug delivery. Continuous subcutaneous application
of the solution containing an equimolar amount of latanoprost acid did not
appreciably influence the IOP. Conclusion Subcutaneous continuous delivery of latanoprost decreased the IOP in the
conscious normotensive Wistar rats in this study. If this effect is confirmed in
humans, it may open the possibility of using peripheral systems of drug delivery,
which could significantly improve patient compliance.
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13
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Faralli JA, Filla MS, Peters DM. Effect of αvβ3 Integrin Expression and Activity on Intraocular Pressure. Invest Ophthalmol Vis Sci 2019; 60:1776-1788. [PMID: 31022732 PMCID: PMC6485315 DOI: 10.1167/iovs.18-26038] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Purpose To determine the effects of αvβ3 integrin expression and activation on intraocular pressure (IOP). Methods Cre+/−β3flox/flox mice were treated with topical tamoxifen eye drops for 5 days to activate Cre and excise the β3 integrin gene from the anterior segment. IOP was measured weekly for 11 weeks using rebound tonometry. Mice were then killed and changes in expression of the β3 integrin subunit in Cre+/− β3flox/flox mice were determined using Western blotting analysis and immunofluorescence microscopy. To determine the effect of αvβ3 integrin activation on outflow facility, porcine organ culture anterior segments (POCAS) were perfused with the αvβ3 integrin-activating antibody AP5 or an isotype IgG control for 21 hours. The effect of αvβ3 integrin activation on IOP was measured over 7 days in C57BL/6J mice intracamerally infused with AP5, AP3, IgG, or PBS. Results Deletion of the β3 integrin subunit using the tamoxifen-inducible Cre-loxP system resulted in a decrease in expression of the β3 integrin subunit in the trabecular meshwork and ciliary muscle. Morphologically no gross changes in the anterior segment were detected. Deletion of the β3 integrin subunit resulted in a significantly (P < 0.05) lower IOP in mice within 2 weeks following the tamoxifen treatment and persisted for 11 weeks. Activating the αvβ3 integrin with the AP5 antibody resulted in a significant (P < 0.05) increase in IOP in C57BL/6J mice and a decrease in outflow facility in 42% of the POCAS. Conclusions These studies demonstrate a role for αvβ3 integrin signaling in the regulation of IOP.
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Affiliation(s)
- Jennifer A Faralli
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States
| | - Mark S Filla
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States
| | - Donna M Peters
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, United States
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14
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Mouse model of ocular hypertension with retinal ganglion cell degeneration. PLoS One 2019; 14:e0208713. [PMID: 30640920 PMCID: PMC6331128 DOI: 10.1371/journal.pone.0208713] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 11/22/2018] [Indexed: 11/16/2022] Open
Abstract
Objectives Ocular hypertension is a primary risk factor for glaucoma and results in retinal ganglion cell (RGC) degeneration. Current animal models of glaucoma lack severe RGC cell death as seen in glaucoma, making assessment of physiological mediators of cell death difficult. We developed a modified mouse model of ocular hypertension whereby long-lasting elevation of intraocular pressure (IOP) is achieved, resulting in significant reproducible damage to RGCs. Results In this model, microbeads are mixed with hyaluronic acid and injected into the anterior chamber of C57BL/6J mice. The hyaluronic acid allows for a gradual release of microbeads, resulting in sustained blockage of Schlemm’s canal. IOP elevation was bimodal during the course of the model’s progression. The first peak occurred 1 hours after beads injection, with an IOP value of 44.69 ± 6.00 mmHg, and the second peak occurred 6–12 days post-induction, with an IOP value of 34.91 ± 5.21 mmHg. RGC damage was most severe in the peripheral retina, with a loss of 64.1% compared to that of untreated eyes, while the midperiphery exhibited a 32.4% loss, 4 weeks following disease induction. Conclusions These results suggest that sustained IOP elevation causes more RGC damage in the periphery than in the midperiphery of the retina. This model yields significant and reproducible RGC degeneration.
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15
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Mild Intraocular Pressure Elevation in Mice Reveals Distinct Retinal Ganglion Cell Functional Thresholds and Pressure-Dependent Properties. J Neurosci 2019; 39:1881-1891. [PMID: 30622167 DOI: 10.1523/jneurosci.2085-18.2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 12/18/2018] [Accepted: 01/03/2019] [Indexed: 01/07/2023] Open
Abstract
Elevation of intraocular pressure (IOP) causes retinal ganglion cell (RGC) dysfunction and death and is a major risk factor for glaucoma. We used a bead injection technique to increase IOP in mice of both genders by an average of ∼3 mmHg for 2 weeks. This level of IOP elevation was lower than that achieved in other studies, which allowed for the study of subtle IOP effects. We used multielectrode array recordings to determine the cellular responses of RGCs exposed to this mild degree of IOP elevation. We found that RGC photopic receptive field (RF) center size and whole-field RGC firing rates were unaffected by IOP elevation. In contrast, we found that the temporal properties of RGC photopic responses in the RF center were accelerated, particularly in ON sustained cells. We also detected a loss of antagonistic surround in several RGC subtypes. Finally, spontaneous firing rate, interspike interval variance, and contrast sensitivity were altered according to the magnitude of IOP exposure and also displayed an IOP-dependent effect. Together, these results suggest that individual RGC physiologic parameters have unique IOP-related functional thresholds that exist concurrently and change following IOP elevation according to specific patterns. Furthermore, even subtle IOP elevation can impart profound changes in RGC function, which in some cases may occur in an IOP-dependent manner. This system of overlapping functional thresholds likely underlies the complex effects of elevated IOP on the retina.SIGNIFICANCE STATEMENT Retinal ganglion cells (RGCs) are the obligate output neurons of the retina and are injured by elevated intraocular pressure (IOP) in diseases such as glaucoma. In this study, a subtle elevation of IOP in mice for 2 weeks revealed distinct IOP-related functional thresholds for specific RGC physiologic parameters and sometimes showed an IOP-dependent effect. These data suggest that overlapping IOP-related thresholds and response profiles exist simultaneously in RGCs and throughout the retina. These overlapping thresholds likely explain the range of RGC responses that occur following IOP elevation and highlight the wide capacity of neurons to respond in a diseased state.
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16
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Fiedorowicz M, Orzel J, Kossowski B, Welniak-Kaminska M, Choragiewicz T, Swiatkiewicz M, Rejdak R, Bogorodzki P, Grieb P. Anterograde Transport in Axons of the Retinal Ganglion Cells and its Relationship to the Intraocular Pressure during Aging in Mice with Hereditary Pigmentary Glaucoma. Curr Eye Res 2017; 43:539-546. [PMID: 29283693 DOI: 10.1080/02713683.2017.1416147] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To establish a relationship between impairment of the anterograde axonal transport (AAT) in the axons of the retinal ganglion cells and the intraocular pressure (IOP) during aging in mice with hereditary glaucoma. METHODS Quantitative in vivo approach based on manganese enhanced magnetic resonance imaging was developed in order to evaluate AAT in 3-, 6-, and 14-month old DBA/2J mice that develop age-dependent pigmentary glaucoma or age-matched C57Bl/6 mice that do not develop any retinal disease. Unilateral intravitreous administration of MnCl2 solution was followed 24 h later by MRI performed to obtain spin-lattice relaxation times (T1) for regions of interest encompassing the superior colliculi (SC) and the lateral geniculate nuclei (LGN). From the MRI scans, the estimates of Mn2+ concentrations in SC and LGN contralateral to the injection site, hence the efficiency of AAT in ON, were obtained. IOP and eye morphology was also monitored. RESULTS In C57Bl/6 mice, AAT to SC was decreasing with age, 30% decrease was noted between 3 and 14 months. The decrease in axonal transport to LGN was less pronounced in this strain. In 3-month-old DBA/2J mice, axonal transport to SC was 30% lower than in 3-month-old C57Bl/6 mice but no significant decrease was noted in 6-month-old animals. However, a decrease of over 95% in axonal transport both to SC and LGN was noted in 14-month-old DBA/2J mice. DBA/2J mice exhibited a sharp increase in IOP at 6 months, which reversed at 14 months but displayed age-dependent elongation of the eyeball and deepening of the anterior chamber. CONCLUSION Failure of AAT to SC of DBA/2J mice during development of pigmentary glaucoma does not follow closely changes in IOP and eye morphology. The relationship between IOP and AAT in optic nerve and tract is complex and may reflect preconditioning mechanism.
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Affiliation(s)
- Michal Fiedorowicz
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland
| | - Jaroslaw Orzel
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland.,b Faculty of Electronics and Information Technology , Warsaw University of Technology , Warsaw , Poland
| | - Bartosz Kossowski
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland.,b Faculty of Electronics and Information Technology , Warsaw University of Technology , Warsaw , Poland.,c Nencki Institute of Experimental Biology , Polish Academy of Sciences , Warsaw , Poland
| | | | | | - Maciej Swiatkiewicz
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland
| | - Robert Rejdak
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland.,d 1st Eye Hospital, Medical University of Lublin , Lublin , Poland
| | - Piotr Bogorodzki
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland.,b Faculty of Electronics and Information Technology , Warsaw University of Technology , Warsaw , Poland
| | - Pawel Grieb
- a Mossakowski Medical Research Centre , Polish Academy of Sciences , Warsaw , Poland
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17
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Fuchs H, Aguilar-Pimentel JA, Amarie OV, Becker L, Calzada-Wack J, Cho YL, Garrett L, Hölter SM, Irmler M, Kistler M, Kraiger M, Mayer-Kuckuk P, Moreth K, Rathkolb B, Rozman J, da Silva Buttkus P, Treise I, Zimprich A, Gampe K, Hutterer C, Stöger C, Leuchtenberger S, Maier H, Miller M, Scheideler A, Wu M, Beckers J, Bekeredjian R, Brielmeier M, Busch DH, Klingenspor M, Klopstock T, Ollert M, Schmidt-Weber C, Stöger T, Wolf E, Wurst W, Yildirim AÖ, Zimmer A, Gailus-Durner V, Hrabě de Angelis M. Understanding gene functions and disease mechanisms: Phenotyping pipelines in the German Mouse Clinic. Behav Brain Res 2017; 352:187-196. [PMID: 28966146 DOI: 10.1016/j.bbr.2017.09.048] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 09/18/2017] [Accepted: 09/25/2017] [Indexed: 02/07/2023]
Abstract
Since decades, model organisms have provided an important approach for understanding the mechanistic basis of human diseases. The German Mouse Clinic (GMC) was the first phenotyping facility that established a collaboration-based platform for phenotype characterization of mouse lines. In order to address individual projects by a tailor-made phenotyping strategy, the GMC advanced in developing a series of pipelines with tests for the analysis of specific disease areas. For a general broad analysis, there is a screening pipeline that covers the key parameters for the most relevant disease areas. For hypothesis-driven phenotypic analyses, there are thirteen additional pipelines with focus on neurological and behavioral disorders, metabolic dysfunction, respiratory system malfunctions, immune-system disorders and imaging techniques. In this article, we give an overview of the pipelines and describe the scientific rationale behind the different test combinations.
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Affiliation(s)
- Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Juan Antonio Aguilar-Pimentel
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Oana V Amarie
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Lore Becker
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Julia Calzada-Wack
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Yi-Li Cho
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Lillian Garrett
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Sabine M Hölter
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Martin Irmler
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Martin Kistler
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Markus Kraiger
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Philipp Mayer-Kuckuk
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Kristin Moreth
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Birgit Rathkolb
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Institute of Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-University München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Jan Rozman
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Patricia da Silva Buttkus
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Irina Treise
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Annemarie Zimprich
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Kristine Gampe
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Christine Hutterer
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Claudia Stöger
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Stefanie Leuchtenberger
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Holger Maier
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Manuel Miller
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Angelika Scheideler
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Moya Wu
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Johannes Beckers
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, Alte Akademie 8, 85354 Freising, Germany
| | - Raffi Bekeredjian
- Department of Cardiology, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Markus Brielmeier
- Research Unit Comparative Medicine, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Dirk H Busch
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Trogerstr. 30, 81675 Munich, Germany
| | - Martin Klingenspor
- Chair of Molecular Nutritional Medicine, Technical University Munich, EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Gregor-Mendel-Str. 2, 85350 Freising-Weihenstephan, Germany; ZIEL - Institute for Food and Health, Technical University Munich, Gregor-Mendel-Str. 2, 85350 Freising-Weihenstephan, Germany
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, Klinikum der Ludwig-Maximilians-Universität München, Ziemssenstr. 1a, 80336 Munich, Germany; German Center for Neurodegenerative Diseases (DZNE), 80336 Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Adolf-Butenandt-Institut, Ludwig-Maximilians-Universität München, Schillerstr. 44, 80336 Munich, Germany; German Center for Vertigo and Balance Disorders, 81377 Munich, Germany
| | - Markus Ollert
- Department of Infection and Immunity, Luxembourg Institute of Health, 29, Rue Henri Koch, 4354 Esch-sur-Alzette, Luxembourg; Department of Dermatology and Allergy Center, Odense Research Center for Anaphylaxis, University of Southern Denmark, 5000 Odense C, Denmark
| | - Carsten Schmidt-Weber
- Center of Allergy & Environment (ZAUM), Technische Universität München, and Helmholtz Zentrum München, Ingolstädter-Landstr., 85764 Neuherberg, Germany
| | - Tobias Stöger
- Institute of Lung Biology and Disease, Member of the German Center for Lung Research (DZL), Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, D-85764 Neuherberg, Germany
| | - Eckhard Wolf
- Institute of Molecular Animal Breeding and Biotechnology, Gene Center, Ludwig-Maximilians-University München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; German Center for Neurodegenerative Diseases (DZNE), 80336 Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Adolf-Butenandt-Institut, Ludwig-Maximilians-Universität München, Schillerstr. 44, 80336 Munich, Germany; Chair of Developmental Genetics, Technische Universität München Freising-Weihenstephan, c/o Helmholtz Zentrum München Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Ali Önder Yildirim
- Institute of Lung Biology and Disease, Member of the German Center for Lung Research (DZL), Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, D-85764 Neuherberg, Germany
| | - Andreas Zimmer
- Institute of Molecular Psychiatry, Medical Faculty, University of Bonn, Sigmund Freud Str. 25, 53127 Bonn, Germany
| | - Valérie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; German Center for Diabetes Research (DZD), Ingolstädter-Landstr. 1, 85764 Neuherberg, Germany; Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, Alte Akademie 8, 85354 Freising, Germany.
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18
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Affiliation(s)
- Mohammadali Almasieh
- Departments of Ophthalmology and Neurology, McGill University, Montreal H4A 3S5, Canada
- Maisonneuve-Rosemont Hospital Research Center and Department of Ophthalmology, University of Montreal, Montreal H1T 2M4, Canada
| | - Leonard A. Levin
- Departments of Ophthalmology and Neurology, McGill University, Montreal H4A 3S5, Canada
- Maisonneuve-Rosemont Hospital Research Center and Department of Ophthalmology, University of Montreal, Montreal H1T 2M4, Canada
- Department of Ophthalmology and Visual Science, University of Wisconsin, Madison, Wisconsin 53706
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Elevated IOP alters the space-time profiles in the center and surround of both ON and OFF RGCs in mouse. Proc Natl Acad Sci U S A 2017; 114:8859-8864. [PMID: 28760976 DOI: 10.1073/pnas.1706994114] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Glaucoma is a leading cause of blindness worldwide, and is characterized by progressive retinal ganglion cell (RGC) death. An experimental model of glaucoma has been established by elevating the intraocular pressure (IOP) via microbead occlusion of ocular fluid outflow in mice. Studies in this model have found visual dysfunction that varied with adaptational state, occurred before anatomical changes, and affected OFF RGCs more than ON RGCs. These results indicate subtle alterations in the underlying retinal circuitry that could help identify disease before irreversible RGC changes. Therefore, we looked at how RGC function was altered with elevated IOP under both photopic and scotopic conditions. We first found that responses to light offset are diminished with IOP elevation along with a concomitant decrease in receptive field center size for OFF RGCs. In addition, the antagonistic surround strength and size was reduced in ON RGCs. Furthermore, elevation of IOP significantly accelerated the photopic temporal tuning of RGC center responses in both ON and OFF RGCs. We found that some of the IOP-induced functional changes to OFF RGCs relied on ON cross-over pathways, indicating dysfunction in inner retinal circuitry. Overall, these results suggest that IOP alters multiple functions in the retina depending on the adaptational state. They provide a basis for designing multiple functional tests for early detection of glaucoma and for circuit-specific therapeutic targets in treatment of this blinding disease.
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20
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Sun D, Moore S, Jakobs TC. Optic nerve astrocyte reactivity protects function in experimental glaucoma and other nerve injuries. J Exp Med 2017; 214:1411-1430. [PMID: 28416649 PMCID: PMC5413323 DOI: 10.1084/jem.20160412] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 12/05/2016] [Accepted: 03/08/2017] [Indexed: 01/06/2023] Open
Abstract
Reactive remodeling of optic nerve head astrocytes is consistently observed in glaucoma and other optic nerve injuries. However, it is unknown whether this reactivity is beneficial or harmful for visual function. In this study, we used the Cre recombinase (Cre)-loxP system under regulation of the mouse glial fibrillary acidic protein promoter to knock out the transcription factor signal transducer and activator of transcription 3 (STAT3) from astrocytes and test the effect this has on reactive remodeling, ganglion cell survival, and visual function after experimental glaucoma and nerve crush. After injury, STAT3 knockout mice displayed attenuated astrocyte hypertrophy and reactive remodeling; astrocytes largely maintained their honeycomb organization and glial tubes. These changes were associated with increased loss of ganglion cells and visual function over a 30-day period. Thus, reactive astrocytes play a protective role, preserving visual function. STAT3 signaling is an important mediator of various aspects of the reactive phenotype within optic nerve astrocytes.
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Affiliation(s)
- Daniel Sun
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, MA 02114
| | - Sara Moore
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, MA 02114
| | - Tatjana C Jakobs
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, MA 02114
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21
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Sawada K, Hiraoka M, Abe A, Kelly R, Shayman JA, Ohguro H. Prolonged Ocular Inflammation in Endotoxin-Induced Uveitis in Lysosomal Phospholipase A2-Deficient Mice. Curr Eye Res 2016; 42:611-616. [DOI: 10.1080/02713683.2016.1214967] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Kanako Sawada
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - Miki Hiraoka
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - Akira Abe
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
| | - Robert Kelly
- Division of Nephrology, Medical Center, University of Michigan, Ann Arbor, MI, USA
| | - James A. Shayman
- Division of Nephrology, Medical Center, University of Michigan, Ann Arbor, MI, USA
| | - Hiroshi Ohguro
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
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22
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Yang X, Hondur G, Tezel G. Antioxidant Treatment Limits Neuroinflammation in Experimental Glaucoma. Invest Ophthalmol Vis Sci 2016; 57:2344-54. [PMID: 27127934 PMCID: PMC4855827 DOI: 10.1167/iovs.16-19153] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Purpose Besides primary neurotoxicity, oxidative stress may compromise the glial immune regulation and shift the immune homeostasis toward neurodegenerative inflammation in glaucoma. We tested this hypothesis through the analysis of neuroinflammatory and neurodegenerative outcomes in mouse glaucoma using two experimental paradigms of decreased or increased oxidative stress. Methods The first experimental paradigm tested the effects of Tempol, a multifunctional antioxidant, given through osmotic mini-pumps for drug delivery by constant infusion. Following a 6-week treatment period after microbead/viscoelastic injection-induced ocular hypertension, retina and optic nerve samples were analyzed for markers of oxidative stress and cytokine profiles using specific bioassays. We also analyzed a redox-sensitive transcriptional regulator of neuroinflammation, namely NF-κB. The second paradigm included a similar analysis of the effects of overloaded oxidative stress on retina and optic nerve inflammation in mice knockout for a major antioxidant enzyme (SOD1−/−). Results Increased antioxidant capacity and decreased protein carbonyls and HNE adducts with Tempol treatment verified the drug delivery and biological function. Among a range of cytokines measured, proinflammatory cytokines, including IL-1, IL-2, IFN-γ, and TNF-α, exhibited more than 2-fold decreased titers in Tempol-treated ocular hypertensive eyes. Antioxidant treatment also resulted in a prominent decrease in NF-κB activation in the ocular hypertensive retina and optic nerve. Although pharmacological treatment limiting the oxidative stress resulted in decreased neuroinflammation, ocular hypertension–induced neuroinflammatory responses were increased in SOD1−/− mice with defective antioxidant response. Conclusions These findings support the oxidative stress–related mechanisms of neuroinflammation and the potential of antioxidant treatment as an immunomodulation strategy for neuroprotection in glaucoma.
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23
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Chandra S, Muir ER, Deo K, Kiel JW, Duong TQ. Effects of Dorzolamide on Retinal and Choroidal Blood Flow in the DBA/2J Mouse Model of Glaucoma. Invest Ophthalmol Vis Sci 2016; 57:826-31. [PMID: 26934140 PMCID: PMC4777278 DOI: 10.1167/iovs.15-18291] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
PURPOSE To test the hypothesis that acute topical dorzolamide (DZ) decreases intraocular pressure (IOP) and increases retinal and choroidal blood flow in the DBA/2J mouse model of glaucoma. METHODS Retinal and choroidal blood flow were measured in 4- and 9-month-old DBA/2J mice, and 4-month C57BL/6 (control) mice under isoflurane anesthesia using magnetic resonance imaging. Ocular blood flow was measured at baseline, and 1 and 2 hours after topical dorzolamide. Intraocular pressure was measured using a rebound tonometer in a subset of animals at the same time points. RESULTS Baseline IOP in the 4-month-old DBA/2J mice and C57BL/6 mice was not significantly different (P > 0.05), and IOP in both groups was less than in the 9-month-old DBA/2J mice (P < 0.05 for both). Compared to baseline, dorzolamide reduced IOP at 1 and 2 hours after dorzolamide in the 4- (P < 0.05) and 9-month-old (P < 0.01) DBA/2J mice, but not in the C57BL/6J mice (P > 0.05). Baseline retinal blood flow was lower in the 4-month and 9-month-old DBA/2J mice compared with the 4-month-old C57BL/6J mice (P < 0.05). Baseline choroidal blood flow in the 9-month-old DBA/2J mice was less than in the C57BL/6J mice (P < 0.05). Compared with baseline, both retinal and choroidal blood flow increased at 1-hour post-dorzolamide and remained elevated 2 hours later in the 9-month-old DBA/2J mice (P < 0.05). CONCLUSIONS Dorzolamide lowers IOP and raises retinal and choroidal blood flow in older DBA/2J mice, consistent with the study hypothesis.
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24
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Becker S, Reinehr S, Dick HB, Joachim SC. [Complement activation after induction of ocular hypertension in an animal model]. Ophthalmologe 2016; 112:41-8. [PMID: 24942221 DOI: 10.1007/s00347-014-3100-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Although an elevated intraocular pressure (IOP) is known as the main risk factor for glaucoma, many studies also showed an involvement of the immune system in this disease. In this study we investigated if a moderate increase in IOP leads to activation of the complement system. METHODS The IOP was elevated experimentally in the left eye of rats, whereas the fellow eye served as the control. The IOP was measured at regular intervals. The number of retinal ganglion cells (RGC) was quantified via NeuN staining. To evaluate the activation of the complement system staining for C3, membrane attack complex (MAC), and mannose-binding lectin (MBL) was performed. Furthermore, we investigated possible glia activation (GFAP and vimentin) and apoptosis (Bax). RESULTS A moderate elevation of the IOP was noted from day 11 after induction of ocular hypertension (OHT) until the end of the study (28 days, p = 0.0005). In the OHT-group significantly fewer RGCs (p = 0.02) were detected. Additionally, we noted significant C3 and MAC activation in the ganglion cell layer (C3, p = 0.001 and MAC, p = 0.02) as well as in the total retina (C3, p = 0.002 and MAC, p = 0.012). An activation via the lectin pathway by MBL staining could not be detected (p = 0.40). At this point in time no alterations with regard to glia cells were noted (GFAP, p = 0.97 and vimentin, p = 0.99). No apoptosis via Bax pathway could be observed (p = 0.90). CONCLUSION The results suggest that the complement system is involved in the loss of RGCs even by a moderate IOP elevation which was indicated by significantly more C3 and MAC depositions in the OHT group.
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Affiliation(s)
- S Becker
- Experimental Eye Research Institute, Universitäts-Augenklinik, Ruhr-Universität Bochum, In der Schornau 23-25, 44892, Bochum, Deutschland
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25
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Gossman CA, Linn DM, Linn C. Glaucoma-inducing Procedure in an In Vivo Rat Model and Whole-mount Retina Preparation. J Vis Exp 2016. [PMID: 27023167 DOI: 10.3791/53831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Glaucoma is a disease of the central nervous system affecting retinal ganglion cells (RGCs). RGC axons making up the optic nerve carry visual input to the brain for visual perception. Damage to RGCs and their axons leads to vision loss and/or blindness. Although the specific cause of glaucoma is unknown, the primary risk factor for the disease is an elevated intraocular pressure. Glaucoma-inducing procedures in animal models are a valuable tool to researchers studying the mechanism of RGC death. Such information can lead to the development of effective neuroprotective treatments that could aid in the prevention of vision loss. The protocol in this paper describes a method of inducing glaucoma - like conditions in an in vivo rat model where 50 µl of 2 M hypertonic saline is injected into the episcleral venous plexus. Blanching of the vessels indicates successful injection. This procedure causes loss of RGCs to simulate glaucoma. One month following injection, animals are sacrificed and eyes are removed. Next, the cornea, lens, and vitreous are removed to make an eyecup. The retina is then peeled from the back of the eye and pinned onto sylgard dishes using cactus needles. At this point, neurons in the retina can be stained for analysis. Results from this lab show that approximately 25% of RGCs are lost within one month of the procedure when compared to internal controls. This procedure allows for quantitative analysis of retinal ganglion cell death in an in vivo rat glaucoma model.
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Affiliation(s)
| | - David M Linn
- Department of Biomedical Sciences, Grand Valley State University
| | - Cindy Linn
- Department of Biological Sciences, Western Michigan University;
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26
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Sawada K, Hiraoka M, Ohguro H. Effect of Antiglaucoma Medicine on Intraocular Pressure in DBA/2J Mice. Ophthalmic Res 2016; 55:205-11. [PMID: 26942413 DOI: 10.1159/000444057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 01/16/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND The DBA/2J mouse strain is known to develop glaucomatous changes. Intraocular pressure (IOP) fluctuations affected by age or antiglaucoma drug administration were compared among three mouse strains, DBA/2J, C57BL/6, and BALB/c. METHODS IOP was measured using the TonoLab tonometer under systemic anesthesia. For each mouse strain, the effects of age and topical administration of antiglaucoma medications (timolol maleate, dorzolamide, brimonidine tartrate, and travoprost) were assessed, and results were compared among the three strains. RESULTS IOP started to rise in DBA/2J mice at 21 weeks of age. The highest values of IOP were distributed from 18 to 51 mm Hg. Eighty percent of DBA/2J mice showed maximum IOP at either 35 or 46 weeks. IOP of C57BL/6 ranged from 9 to 14 mm Hg as the mice aged. Treatment with any of the antiglaucoma medications resulted in IOP-lowering effects in all three strains. The difference in levels before and after administration ranged from 6 to 10 mm Hg on average in DBA/2J. CONCLUSION DBA/2J mice are a useful animal model to study the effects of antiglaucoma therapy.
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Affiliation(s)
- Kanako Sawada
- Department of Ophthalmology, School of Medicine, Sapporo Medical University, Sapporo, Japan
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27
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Wang J, Dong Y. Characterization of intraocular pressure pattern and changes of retinal ganglion cells in DBA2J glaucoma mice. Int J Ophthalmol 2016; 9:211-7. [PMID: 26949637 DOI: 10.18240/ijo.2016.02.05] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 09/09/2015] [Indexed: 01/20/2023] Open
Abstract
AIM To characterize the pattern of intraocular pressure (IOP) change and the deficit of retinal ganglion cells (RGCs) in DBA2J, which is most well-characterized chronic glaucoma mouse model and wild type (WT) C57bl/6 mice, and to study the relationship between IOP change and RGCs deficit. METHODS IOP was monitored with a rebound tonometer in WT C57bl/6 and DBA2J mice from 3 to 15-month-old. Retinal function was evaluated by dark-adapted electroretinogram (ERG) in DBA2J and WT mice of 15-month-old. A dye (Neurobiotin) was applied to optic nerve stump to retrograde label RGCs. TO-PRO-3 visualized all nuclei of cells in the RGC layer. RESULTS The IOP in WT mice was 9.03±0.6 mm Hg on average and did not increase significantly as aging. The IOP in DBA2J mice, arranging from 7.2 to 28 mm Hg, was increasing significantly as aging, and it was normal at 3-month-old compared with WT mice, slightly increased from 7-month-old and increased in 50% animals at 11-month-old and in 38% animals at 15-month-old. The RGCs density in DBA2J mice started reducing by 7-month-old, continuously decreased until reached about 20% of RGC in WT retina by 15-month-old. RGC density was not linearly correlated with IOP in 15-month-old DBA2J mice. The amplitude of positive scotopic threshold response, and negative scotopic threshold response of ERG were significantly reduced in DBA2J mice of 15-month-old than that in age-paired WT mice. CONCLUSION The present study found that DBA2J mice display pathological and functional deficits of the retina that was not linearly correlated with IOP.
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Affiliation(s)
- Jing Wang
- Cullen Eye Institute, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Yu Dong
- Cullen Eye Institute, Baylor College of Medicine, Houston, Texas 77030, USA
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28
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Gao S, Jakobs TC. Mice Homozygous for a Deletion in the Glaucoma Susceptibility Locus INK4 Show Increased Vulnerability of Retinal Ganglion Cells to Elevated Intraocular Pressure. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:985-1005. [PMID: 26883755 DOI: 10.1016/j.ajpath.2015.11.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/30/2015] [Accepted: 11/17/2015] [Indexed: 12/13/2022]
Abstract
A genomic region located on chromosome 9p21 is associated with primary open-angle glaucoma and normal tension glaucoma in genome-wide association studies. The genomic region contains the gene for a long noncoding RNA called CDKN2B-AS, two genes that code for cyclin-dependent kinase inhibitors 2A and 2B (CDKN2A/p16(INK4A) and CDKN2B/p15(INK4B)) and an additional protein (p14(ARF)). We used a transgenic mouse model in which 70 kb of murine chromosome 4, syntenic to human chromosome 9p21, are deleted to study whether this deletion leads to a discernible phenotype in ocular structures implicated in glaucoma. Homozygous mice of this strain were previously reported to show persistent hyperplastic primary vitreous. Fundus photography and optical coherence tomography confirmed that finding but showed no abnormalities for heterozygous mice. Optokinetic response, eletroretinogram, and histology indicated that the heterozygous and mutant retinas were normal functionally and morphologically, whereas glial cells were activated in the retina and optic nerve head of mutant eyes. In quantitative PCR, CDKN2B expression was reduced by approximately 50% in the heterozygous mice and by 90% in the homozygous mice, which suggested that the CDKN2B knock down had no deleterious consequences for the retina under normal conditions. However, compared with wild-type and heterozygous animals, the homozygous mice are more vulnerable to retinal ganglion cell loss in response to elevated intraocular pressure.
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Affiliation(s)
- Shan Gao
- Department of Ophthalmology, The First Affiliated Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China; Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts
| | - Tatjana C Jakobs
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary/Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts.
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Quigley HA, Pitha IF, Welsbie DS, Nguyen C, Steinhart MR, Nguyen TD, Pease ME, Oglesby EN, Berlinicke CA, Mitchell KL, Kim J, Jefferys JJ, Kimball EC. Losartan Treatment Protects Retinal Ganglion Cells and Alters Scleral Remodeling in Experimental Glaucoma. PLoS One 2015; 10:e0141137. [PMID: 26505191 PMCID: PMC4624713 DOI: 10.1371/journal.pone.0141137] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 10/05/2015] [Indexed: 12/20/2022] Open
Abstract
Purpose To determine if oral losartan treatment decreases the retinal ganglion cell (RGC) death caused by experimental intraocular pressure (IOP) elevation in mice. Methods We produced IOP increase in CD1 mice and performed unilateral optic nerve crush. Mice received oral losartan, spironolactone, enalapril, or no drug to test effects of inhibiting angiotensin receptors. IOP was monitored by Tonolab, and blood pressure was monitored by tail cuff device. RGC loss was measured in masked axon counts and RGC bodies by β-tubulin labeling. Scleral changes that could modulate RGC injury were measured including axial length, scleral thickness, and retinal layer thicknesses, pressure-strain behavior in inflation testing, and study of angiotensin receptors and pathways by reverse transcription polymerase chain reaction, Western blot, and immunohistochemistry. Results Losartan treatment prevented significant RGC loss (median loss = 2.5%, p = 0.13), while median loss with water, spironolactone, and enalapril treatments were 26%, 28% and 43%; p < 0.0001). The lower RGC loss with losartan was significantly less than the loss with spironolactone or enalapril (regression model p = 0.001; drug treatment group term p = 0.01). Both losartan and enalapril significantly lowered blood pressure (p< 0.001), but losartan was protective, while enalapril led to worse than water-treated RGC loss. RGC loss after crush injury was unaffected by losartan treatment (difference from control p = 0.9). Survival of RGC in cell culture was not prolonged by sartan treatment. Axonal transport blockade after 3 day IOP elevations was less in losartan-treated than in control glaucoma eyes (p = 0.007). Losartan inhibited effects of glaucoma, including reduction in extracellular signal-related kinase activity and modification of glaucoma-related changes in scleral thickness and creep under controlled IOP. Conclusions The neuroprotective effect of losartan in mouse glaucoma is associated with adaptive changes in the sclera expressed at the optic nerve head.
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Affiliation(s)
- Harry A. Quigley
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail:
| | - Ian F. Pitha
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Derek S. Welsbie
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Cathy Nguyen
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Matthew R. Steinhart
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Thao D. Nguyen
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Mary Ellen Pease
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Ericka N. Oglesby
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Cynthia A. Berlinicke
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Katherine L. Mitchell
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jessica Kim
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Joan J. Jefferys
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Elizabeth C. Kimball
- The Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States of America
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Morrison JC, Cepurna WO, Johnson EC. Modeling glaucoma in rats by sclerosing aqueous outflow pathways to elevate intraocular pressure. Exp Eye Res 2015; 141:23-32. [PMID: 26003399 DOI: 10.1016/j.exer.2015.05.012] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 05/18/2015] [Accepted: 05/19/2015] [Indexed: 12/14/2022]
Abstract
Injection of hypertonic saline via episcleral veins toward the limbus in laboratory rats can produce elevated intraocular pressure (IOP) by sclerosis of aqueous humor outflow pathways. This article describes important anatomic characteristics of the rat optic nerve head (ONH) that make it an attractive animal model for human glaucoma, along with the anatomy of rat aqueous humor outflow on which this technique is based. The injection technique itself is also described, with the aid of a supplemental movie, including necessary equipment and specific tips to acquire this skill. Outcomes of a successful injection are presented, including IOP elevation and patterns of optic nerve injury. These concepts are then specifically considered in light of the use of this model to assess potential neuroprotective therapies. Advantages of the hypertonic saline model include a delayed and relatively gradual IOP elevation, likely reproduction of scleral and ONH stresses and strains that may be important in producing axonal injury, and its ability to be applied to any rat (and potentially mouse) strain, leaving the unmanipulated fellow eye as an internal control. Challenges include the demanding surgical skill required by the technique itself, a wide range of IOP response, and mild corneal clouding in some animals. However, meticulous application of the principles detailed in this article and practice will allow most researchers to attain this useful skill for studying cellular events of glaucomatous optic nerve damage.
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Affiliation(s)
- John C Morrison
- The Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, USA.
| | - William O Cepurna
- The Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, USA
| | - Elaine C Johnson
- The Kenneth C. Swan Ocular Neurobiology Laboratory, Casey Eye Institute, Oregon Health and Science University, USA
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Nusbaum DM, Wu SM, Frankfort BJ. Elevated intracranial pressure causes optic nerve and retinal ganglion cell degeneration in mice. Exp Eye Res 2015; 136:38-44. [PMID: 25912998 DOI: 10.1016/j.exer.2015.04.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 04/20/2015] [Accepted: 04/22/2015] [Indexed: 02/08/2023]
Abstract
The purpose of this study was to develop a novel experimental system for the modulation and measurement of intracranial pressure (ICP), and to use this system to assess the impact of elevated ICP on the optic nerve and retinal ganglion cells (RGCs) in CD1 mice. This system involved surgical implantation of an infusion cannula and a radiowave based pressure monitoring probe through the skull and into the subarachnoid space. The infusion cannula was used to increase ICP, which was measured by the probe and transmitted to a nearby receiver. The system provided robust and consistent ICP waveforms, was well tolerated, and was stable over time. ICP was elevated to approximately 30 mmHg for one week, after which we assessed changes in optic nerve structure with transmission electron microscopy in cross section and RGC numbers with antibody staining in retinal flat mounts. ICP elevation resulted in optic nerve axonal loss and disorganization, as well as RGC soma loss. We conclude that the controlled manipulation of ICP in active, awake mice is possible, despite their small size. Furthermore, ICP elevation results in visual system phenotypes of optic nerve and RGC degeneration, suggesting that this model can be used to study the impact of ICP on the visual system. Potentially, this model can also be used to study the relationship between ICP and IOP, as well diseases impacted by ICP variation such as glaucoma, idiopathic intracranial hypertension, and the spaceflight-related visual impairment intracranial pressure syndrome.
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Affiliation(s)
- Derek M Nusbaum
- Department of Internal Medicine, Baylor College of Medicine, Houston, TX, USA; Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Samuel M Wu
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA; Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Benjamin J Frankfort
- Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA; Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA.
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Liu LF, Huang CK, Zhang MZ. Reliability of Tonolab measurements in rats. Int J Ophthalmol 2014; 7:930-4. [PMID: 25540741 DOI: 10.3980/j.issn.2222-3959.2014.06.03] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 06/20/2014] [Indexed: 12/17/2022] Open
Abstract
AIM To assess the repeatability and reproducibility of Tonolab tonometer in rats with high intraocular pressure (IOP) and evaluate its ability to detect IOP changes in rats with general anaesthesia. METHODS Left eyes of adult Fischer rats (F344) were photocoagulated by 532 nm diode laser to induce high IOP. Hypertensive eyes of 30 conscious rats were randomly chosen to measure IOP on a single occasion. Two observers independently and alternately undertook IOP measurements consecutively for three times using the same Tonolab tonometer blind to the other observer's IOP measurements. The within subject standard deviation (Sw), coefficient of variation (CVw) (100×Sw/overall mean), and intraclass correlation coefficient (ICC) were calculated to evaluate intra-observer repeatability. Inter-observer difference was analysed by using 95% limits of agreement described by Bland-Altman and paired sample t-test. Also, another 13 normal F344 rats were intraperitoneally administrated with ketamine/xylazine or chloral hydrate, and IOPs of both eyes were measured by a single operator once every 5min until animals came to conscious. IOPs at various time points were compared by using one-way ANOVAs. RESULTS Mean IOP was 35.58 mm Hg (range 17.33 to 65.33 mm Hg). For intraobserver repeatability, the Sw, CVw and ICC of high IOP for two observers were 5.20 mm Hg/3.41 mm Hg, 9.98%/8.08% and 0.820/0.928 respectively. The inter-observer difference was 14.76%±19.76% of the mean IOP of two observers, with a 95% limits of agreement -23.97% to 53.50%, and the difference between mean IOP of these two observers was statistically significant (P=0.001). IOPs dropped slightly during the first 15min post-aneathesia, with a IOP change between 0.17 and 1.17 mm Hg. IOPs changed from basline of 11.75±2.05 mm Hg (n=12) to 8.75±1.06 mm Hg 20min post-anesthesia (P=0.001), and this hypotensive condition persisted until 80min post-anesthesia. CONCLUSION In this sample of hypertensive rats, Tonolab measurements demonstrated high levels of intraobserver repeatability, however, its interobserver reproducibility was poor. Longitudinal changes of IOP caused by genral anaesthesia can be sensitively detected by Tonolab. So we suggested that measurements of IOP using Tonolab are best measured by a single observer, and it could be included in experimental glaucoma.
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Affiliation(s)
- Li-Fang Liu
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
| | - Chu-Kai Huang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
| | - Ming-Zhi Zhang
- Joint Shantou International Eye Center of Shantou University and the Chinese University of Hong Kong, Shantou 515041, Guangdong Province, China
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Khan AK, Tse DY, van der Heijden ME, Shah P, Nusbaum DM, Yang Z, Wu SM, Frankfort BJ. Prolonged elevation of intraocular pressure results in retinal ganglion cell loss and abnormal retinal function in mice. Exp Eye Res 2014; 130:29-37. [PMID: 25450059 DOI: 10.1016/j.exer.2014.11.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 10/24/2014] [Accepted: 11/12/2014] [Indexed: 12/25/2022]
Abstract
The purpose of this study was to assess the impact of prolonged intraocular pressure (IOP) elevation on retinal anatomy and function in a mouse model of experimental glaucoma. IOP was elevated by anterior chamber injection of a fixed combination of polystyrene beads and sodium hyaluronate, and maintained via re-injection after 24 weeks. IOP was measured weekly with a rebound tonometer for 48 weeks. Histology was assessed with a combination of retrograde labeling and antibody staining. Retinal physiology and function was assessed with dark-adapted electroretinograms (ERGs). Comparisons between bead-injected animals and various controls were conducted at both 24 and 48 weeks after bead injection. IOP was elevated throughout the study. IOP elevation resulted in a reduction of retinal ganglion cell (RGCs) and an increase in axial length at both 24 and 48 weeks after bead injection. The b-wave amplitude of the ERG was increased to the same degree in bead-injected eyes at both time points, similar to previous studies. The positive scotopic threshold response (pSTR) amplitude, a measure of RGC electrical function, was diminished at both 24 and 48 weeks when normalized to the increased b-wave amplitude. At 48 weeks, the pSTR amplitude was reduced even without normalization, suggesting more profound RGC dysfunction. We conclude that injection of polystyrene beads and sodium hyaluronate causes chronic IOP elevation which results in phenotypes of stable b-wave amplitude increase and progressive pSTR amplitude reduction, as well as RGC loss and axial length elongation.
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Affiliation(s)
- A Kareem Khan
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Dennis Y Tse
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA; School of Optometry, Hong Kong Polytechnic University, Hong Kong
| | - Meike E van der Heijden
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Priya Shah
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Derek M Nusbaum
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Zhuo Yang
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA
| | - Samuel M Wu
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
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Kimball EC, Nguyen C, Steinhart MR, Nguyen TD, Pease ME, Oglesby EN, Oveson BC, Quigley HA. Experimental scleral cross-linking increases glaucoma damage in a mouse model. Exp Eye Res 2014; 128:129-40. [PMID: 25285424 PMCID: PMC4254118 DOI: 10.1016/j.exer.2014.08.016] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/21/2014] [Accepted: 08/07/2014] [Indexed: 12/12/2022]
Abstract
The purpose of this study was to assess the effect of a scleral cross-linking agent on susceptibility to glaucoma damage in a mouse model.CD1 mice underwent 3 subconjunctival injections of 0.5 M glyceraldehyde (GA) in 1 week, then had elevated intraocular pressure (IOP) induced by bead injection. Degree of cross-linking was measured by enzyme-linked immunosorbent assay (ELISA), scleral permeability was measured by fluorescence recovery after photobleaching (FRAP), and the mechanical effects of GA exposure were measured by inflation testing. Control mice had buffer injection or no injection in 2 separate glaucoma experiments. IOP was monitored by Tonolab and retinal ganglion cell (RGC) loss was measured by histological axon counting. To rule out undesirable effects of GA, we performed electroretinography and detailed histology of the retina. GA exposure had no detectable effects on RGC number, retinal structure or function either histologically or electrophysiologically. GA increased cross-linking of sclera by 37% in an ELISA assay, decreased scleral permeability (FRAP, p = 0.001), and produced a steeper pressure-strain behavior by in vitro inflation testing. In two experimental glaucoma experiments, GA-treated eyes had greater RGC axon loss from elevated IOP than either buffer-injected or control eyes, controlling for level of IOP exposure over time (p = 0.01, and 0.049, multivariable regression analyses). This is the first report that experimental alteration of the sclera, by cross-linking, increases susceptibility to RGC damage in mice.
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Affiliation(s)
- Elizabeth C Kimball
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA.
| | - Cathy Nguyen
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Matthew R Steinhart
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Thao D Nguyen
- The Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Mary E Pease
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Ericka N Oglesby
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Brian C Oveson
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Harry A Quigley
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD, USA
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A rat experimental model of glaucoma incorporating rapid-onset elevation of intraocular pressure. Sci Rep 2014; 4:5910. [PMID: 25081302 PMCID: PMC4118189 DOI: 10.1038/srep05910] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 07/01/2014] [Indexed: 11/08/2022] Open
Abstract
Glaucoma is a chronic disease that causes structural and functional damage to retinal ganglion cells (RGC). The currently employed therapeutic options are not sufficient to prevent vision loss in patients with glaucoma; therefore, there is a need to develop novel therapies, which requires the creation of functional, repeatable and easy-to-utilize animal models for use in pre-clinical studies. The currently available models ensure only low to moderate damage in optic nerves, with high variation in the outcomes and poor repeatability. We have developed an effective and reproducible rat glaucoma model based on a previous idea for a "Bead Model" in mice, which could be useful in future glaucoma research. Additionally, in an attempt to achieve rapid elevation of Intraocular Pressure (IOP), we included an initial "high-pressure injury" as part of this method, which serves as the equivalent of a severe glaucoma attack. These modifications made it possible to achieve longer lasting IOP elevation with chronic damage of retinal ganglion cells.
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Park DY, Lee J, Park I, Choi D, Lee S, Song S, Hwang Y, Hong KY, Nakaoka Y, Makinen T, Kim P, Alitalo K, Hong YK, Koh GY. Lymphatic regulator PROX1 determines Schlemm's canal integrity and identity. J Clin Invest 2014; 124:3960-74. [PMID: 25061877 DOI: 10.1172/jci75392] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 05/30/2014] [Indexed: 12/30/2022] Open
Abstract
Schlemm's canal (SC) is a specialized vascular structure in the eye that functions to drain aqueous humor from the intraocular chamber into systemic circulation. Dysfunction of SC has been proposed to underlie increased aqueous humor outflow (AHO) resistance, which leads to elevated ocular pressure, a factor for glaucoma development in humans. Here, using lymphatic and blood vasculature reporter mice, we determined that SC, which originates from blood vessels during the postnatal period, acquires lymphatic identity through upregulation of prospero homeobox protein 1 (PROX1), the master regulator of lymphatic development. SC expressed lymphatic valve markers FOXC2 and integrin α9 and exhibited continuous vascular endothelial-cadherin (VE-cadherin) junctions and basement membrane, similar to collecting lymphatics. SC notably lacked luminal valves and expression of the lymphatic endothelial cell markers podoplanin and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1). Using an ocular puncture model, we determined that reduced AHO altered the fate of SC both during development and under pathologic conditions; however, alteration of VEGF-C/VEGFR3 signaling did not modulate SC integrity and identity. Intriguingly, PROX1 expression levels linearly correlated with SC functionality. For example, PROX1 expression was reduced or undetectable under pathogenic conditions and in deteriorated SCs. Collectively, our data indicate that PROX1 is an accurate and reliable biosensor of SC integrity and identity.
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Boussommier-Calleja A, Overby DR. The influence of genetic background on conventional outflow facility in mice. Invest Ophthalmol Vis Sci 2013; 54:8251-8. [PMID: 24235015 DOI: 10.1167/iovs.13-13025] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Intraocular pressure (IOP) varies between genetically distinct strains of mice. The purpose was to test the hypothesis that strain-dependent differences in IOP are attributable to differences in conventional outflow facility (C). METHODS The IOP was measured by rebound tonometry in conscious or anesthetized BALB/cJ, C57BL/6J, and CBA/J mice (N = 6-10 per strain). Conventional outflow facility was measured by ex vivo perfusion of enucleated eyes (N = 9-10 per strain). RESULTS Conscious IOP varied between strains, being highest in CBA/J (14.5 ± 0.9 mm Hg, mean ± SD), intermediate in C57BL/6J (12.3 ± 1.0 mm Hg), and lowest in BALB/cJ (10.6 ± 1.8 mm Hg) mice. Anesthesia reduced IOP and eliminated any detectable differences between strains. Conventional outflow facility also varied between strains, but, in contrast to IOP, C was lowest in CBA/J (0.0113 ± 0.0031 μL/min/mm Hg) and highest in BALB/cJ (0.0164 ± 0.0059 μL/min/mm Hg). Like IOP, C was intermediate in C57BL/6J (0.0147 ± 0.0029 μL/min/mm Hg). There was a strong correlation between conscious IOP and outflow resistance (1/C) from individual eyes across all three strains, revealing that 70% of the variation in IOP was attributable to variation in outflow resistance. CONCLUSIONS Differences in IOP among three genetically distinct murine strains are attributable largely to differences in conventional outflow facility. These results motivate further studies using mice to identify the morphologic and genetic factors that underlie IOP regulation within the conventional outflow pathway.
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Cyp1b1 mediates periostin regulation of trabecular meshwork development by suppression of oxidative stress. Mol Cell Biol 2013; 33:4225-40. [PMID: 23979599 DOI: 10.1128/mcb.00856-13] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Mutation in CYP1B1 has been reported for patients with congenital glaucoma. However, the underlying mechanisms remain unknown. Here we show increased diurnal intraocular pressure (IOP) in Cyp1b1-deficient (Cyp1b1(-/-)) mice. Cyp1b1(-/-) mice presented ultrastructural irregular collagen distribution in their trabecular meshwork (TM) tissue along with increased oxidative stress and decreased levels of periostin (Postn). Increased levels of oxidative stress and decreased levels of Postn were also detected in human glaucomatous TM tissues. Furthermore, Postn-deficient mice exhibited TM tissue ultrastructural abnormalities similar to those of Cyp1b1(-/-) mice. Administration of the antioxidant N-acetylcysteine (NAC) restored structural abnormality of TM tissue in Cyp1b1(-/-) mice. In addition, TM cells prepared from Cyp1b1(-/-) mice exhibited increased oxidative stress, altered adhesion, and decreased levels of Postn. These aberrant cellular responses were reversed in the presence of NAC or by restoration of Cyp1b1 expression. Cyp1b1 knockdown or inhibition of CYP1B1 activity in Cyp1b1(+/+) TM cells resulted in a Cyp1b1(-/-) phenotype. Thus, metabolic activity of CYP1B1 contributes to oxidative homeostasis and ultrastructural organization and function of TM tissue through modulation of Postn expression.
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Chatterjee A, Oh DJ, Kang MH, Rhee DJ. Central corneal thickness does not correlate with TonoLab-measured IOP in several mouse strains with single transgenic mutations of matricellular proteins. Exp Eye Res 2013; 115:106-12. [PMID: 23806329 DOI: 10.1016/j.exer.2013.06.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/13/2013] [Accepted: 06/15/2013] [Indexed: 02/08/2023]
Abstract
Accurate and reliable measurement of intraocular pressure (IOP) is crucial in the study of glaucoma using the mouse model. The purpose of this study was to determine the relationship between TonoLab-measured IOP and central corneal thickness (CCT) in mouse strains with single gene mutations of matricellular proteins. Wild-type (WT) and transgenic mouse strains with single gene mutations (KO) of thrombospondin-1 (TSP-1), thrombospondin-2 (TSP-2), osteopontin (OPN), hevin, and secreted protein acidic rich in cysteine (SPARC) were imaged at six weeks using optical coherence tomography (Stratus, Zeiss) to determine CCT. IOP was measured between 11am and 3pm using TonoLab, one week later. For all measurements, mice were anesthetized using intraperitoneal injection ketamine:xylazine. CCT and IOP were measured in 583 mice (TSP-1 n = 71 and 41, TSP-2 n = 60 and 32, OPN n = 81 and 50, hevin n = 59 and 76, SPARC n = 54 and 59, WT and KO, respectively). Mean CCT was 5-6% lower in three KO strains-TSP-1, OPN, and SPARC-compared to their corresponding WT (p = 1.55 × 10(-7), 1.63 × 10(-11), and 1.91 × 10(-7), respectively). The mean IOP was 8.3%, 6.6%, and 15.1% lower in three KO strains-TSP-1, TSP-2, and SPARC-compared to corresponding WT (p = 2.11 × 10(-5), 2.93 × 10(-3), and 3.76 × 10(-9), respectively. Linear regression of IOP versus CCT yielded no statistically significant within-strain correlations for TSP-1 (p = 0.12 and 0.073), TSP-2 (p = 0.473 and 0.92), OPN (p = 0.212 and 0.916), Hevin (p = 0.746 and 0.257), and SPARC (p = 0.080 and 0.056), reported as p-values considering a null hypothesis of zero slope (WT and KO, respectively). Neither C57-derived strains (TSP-1 and OPN) nor 129-derived strains (TSP-2, hevin, SPARC) demonstrated a correlation between mean IOP and mean CCT across different strains (p = 0.75 and p = 0.53, respectively). Taken together, these results indicate that CCT is not required to interpret TonoLab IOP readings in the mice when CCT varies 10% about the mean. This does not exclude the possibility of an IOP-CCT correlation for CCT values outside this range or for inter-strain comparisons where the mean CCT differs more than 10%.
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Affiliation(s)
- Ayan Chatterjee
- Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, 243 Charles Street, Boston, MA 02114, USA
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Robertson JV, Siwakoti A, West-Mays JA. Altered expression of transforming growth factor beta 1 and matrix metalloproteinase-9 results in elevated intraocular pressure in mice. Mol Vis 2013; 19:684-95. [PMID: 23559862 PMCID: PMC3611945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Accepted: 03/19/2013] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Extracellular matrix remodeling is thought to have profound effects on tissue architecture and associated function. We have shown previously that overexpression of transforming growth factor beta (TGFβ), which stimulates matrix accumulation, results in altered morphology, cataract, and ocular hypertension in rodents. We have further shown that TGFβ-induced cataracts can be mitigated through inhibition of the matrix metalloproteinases (MMP) MMP-2 and MMP-9. We therefore sought to determine whether loss of MMP expression also altered TGFβ-induced changes in intraocular pressure (IOP). METHODS To carry out this study, TGFβ1 transgenic mice were bred onto a MMP-9 null background. IOP measurements were made at 1- to 2-, 2- to 3-, and 3- to 4-month time points using a TonoLab rebound tonometer. Histological and immunofluorescence findings were obtained at the same time points. RESULTS Our results demonstrate that lens-specific expression of TGFβ1 in mice results in altered morphology of the anterior segment and an accompanying significant increase in IOP. TGFβ1 transgenic mice bred onto the MMP-9 null background exhibited a further increase in IOP. Interestingly, the MMP-9-deficient animals (without the TGFβ transgene), which exhibited normal angle morphology, had increased IOP levels compared to their wild-type littermates. CONCLUSION These results indicate that TGFβ and MMP-9 likely act independently in regulating IOP. Additionally, MMP-9 plays an important role in maintaining IOP, and further investigation into the mechanisms of MMP-9 activity in the anterior angle may give clues to how extracellular matrix remodeling participates in ocular hypertension and glaucoma.
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Frankfort BJ, Khan AK, Tse DY, Chung I, Pang JJ, Yang Z, Gross RL, Wu SM. Elevated intraocular pressure causes inner retinal dysfunction before cell loss in a mouse model of experimental glaucoma. Invest Ophthalmol Vis Sci 2013; 54:762-70. [PMID: 23221072 DOI: 10.1167/iovs.12-10581] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
PURPOSE We assessed the relationship among intraocular pressure (IOP), histology, and retinal function changes in a mouse model of induced, chronic, mild ocular hypertension. METHODS IOP was elevated experimentally via anterior chamber injection of polystyrene beads and measured twice weekly with a rebound tonometer. Histology was assessed with a combination of neurobiotin (NB) retrograde labeling of retinal ganglion cells (RGCs) and TO-PRO3 staining. Retinal function was assessed with serial dark-adapted electroretinograms (ERGs) optimized for detection of the a-wave, b-wave, and positive and negative scotopic threshold responses (pSTR, nSTR). Comparisons between bead-injected and saline-injected (control) eyes were conducted. RESULTS IOP remained elevated for at least 3 months following a single injection of polystyrene beads. Elevated IOP resulted in a mild, progressive reduction of RGCs, and a mild increase in axial length at 6 and 12 weeks after bead injection. The raw b-wave amplitude was increased shortly after IOP elevation, but the raw a-wave, pSTR, and nSTR amplitudes were unchanged. pSTR and nSTR amplitudes were normalized to the increased b-wave. With this normalization, the pSTR amplitude was decreased shortly after IOP elevation. CONCLUSIONS Polystyrene bead injection results in a mild, chronic elevation of IOP that recapitulates several critical aspects of human ocular hypertension and glaucoma, and results in early changes in retinal electrical function that precede histologic changes. It is possible that glaucoma associated with elevated IOP involves the early disruption of a complex combination of retinal synapses.
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Affiliation(s)
- Benjamin J Frankfort
- Cullen Eye Institute, Department of Ophthalmology, Baylor College of Medicine, Houston, Texas 77030, USA.
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Ritchey ER, Zelinka CP, Tang J, Liu J, Fischer AJ. The combination of IGF1 and FGF2 and the induction of excessive ocular growth and extreme myopia. Exp Eye Res 2012; 99:1-16. [PMID: 22695224 DOI: 10.1016/j.exer.2012.03.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Revised: 03/21/2012] [Accepted: 03/28/2012] [Indexed: 01/01/2023]
Abstract
Different growth factors have been shown to influence the development of form-deprivation myopia and lens-induced ametropias. However, growth factors have relatively little effect on the growth of eyes with unrestricted vision. We investigate whether the combination of insulin-like growth factor 1 (IGF1) and fibroblast growth factor 2 (FGF2) influence ocular growth in eyes with unrestricted vision. Different doses of IGF1 and FGF2 were injected into the vitreous chamber of postnatal chicks. Measurements of ocular dimensions and intraocular pressure (IOP) were made during and at the completion of different treatment paradigms. Histological and immunocytochemical analyses were performed to assess cell death, cellular proliferation and integrity of ocular tissues. Treated eyes had significant increases in equatorial diameter and vitreous chamber depth. With significant variability between individuals, IGF1/FGF2-treatment caused hypertrophy of lens and ciliary epithelia, lens thickness was increased, and anterior chamber depth was decreased. Treated eyes developed myopia, in excess of 15 diopters of refractive error. Shortly after treatment, eyes had increased intraocular pressure (IOP), which was increased in a dose-dependent manner. Seven days after treatment with IGF1 and FGF2 changes to anterior chamber depth, lens thickness and elevated IOP were reduced, whereas increases in the vitreous chamber were persistent. Some damage to ganglion cells was detected in peripheral regions of the retina at 7 days after treatment. We conclude that the extreme myopia in IGF1/FGF2-treated eyes results from increased vitreous chamber depth, decreased anterior chamber depth, and changes in the lens. We propose that factor-induced ocular enlargement and myopia result from changes to the sclera, lens and anterior chamber depth.
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Affiliation(s)
- Eric R Ritchey
- College of Optometry, The Ohio State University, Columbus, OH 43210, USA
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Steinhart MR, Cone FE, Nguyen C, Nguyen TD, Pease ME, Puk O, Graw J, Oglesby EN, Quigley HA. Mice with an induced mutation in collagen 8A2 develop larger eyes and are resistant to retinal ganglion cell damage in an experimental glaucoma model. Mol Vis 2012; 18:1093-106. [PMID: 22701298 PMCID: PMC3374490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 04/25/2012] [Indexed: 12/02/2022] Open
Abstract
PURPOSE To study susceptibility to glaucoma injury as it may be affected by mutations in ocular connective tissue components. METHODS Mice homozygous for an N-ethyl-N-nitrosourea induced G257D exchange (Gly to Asp) missense mutation (Aca23) in their collagen 8A2 gene were studied to measure intraocular pressure (IOP), axial length and width, number of retinal ganglion cells (RGC), and inflation responses. Three month old homozygous Aca23 mutant and wild type (WT) mice had 6 weeks exposure to elevated IOP induced by polystyrene microbead injection. Additional Aca23 and matched controls were studied at ages of 10 and 18 months. RESULTS Aca23 mice had no significant difference from WT in IOP level, and in both strains IOP rose with age. In multivariable models, axial length and width were significantly larger in Aca23 than WT, became larger with age, and were larger after exposure to glaucoma (n=227 mice). From inflation test data, the estimates of scleral stress resultants in Aca23 mice were similar to age-matched and younger WT C57BL/6 (B6) mice, while the strain estimates for Aca23 were significantly less than those for either WT group in the mid-sclera and in some of the more anterior scleral measures (p<0.001; n=29, 22, 20 eyes in Aca23, older WT, younger WT, respectively). With chronic IOP elevation, Aca23 eyes increased 9% in length and 7% in width, compared to untreated fellow eyes (p<0.05, <0.01). With similar elevated IOP exposure, WT eyes enlarged proportionately twice as much as Aca23, increasing in length by 18% and in nasal-temporal width by 13% (both p<0.001, Mann-Whitney test). In 4 month old control optic nerves, mean RGC axon number was not different in Aca23 and WT (46,905±7,592, 43,628±11,162, respectively; p=0.43, Mann-Whitney test, n=37 and 29). With chronic glaucoma, Aca23 mice had a mean axon loss of only 0.57±17%, while WT mice lost 21±31% (median loss: 1% versus 10%, n=37, 29, respectively; p=0.001; multivariable model adjusting for positive integral IOP exposure). CONCLUSIONS The Aca23 mutation in collagen 8α2 is the first gene defect found to alter susceptibility to experimental glaucoma, reducing RGC loss possibly due to differences in mechanical behavior of the sclera. Detailed study of the specific changes in scleral connective tissue composition and responses to chronic IOP elevation in this strain could produce new therapeutic targets for RGC neuroprotection.
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Affiliation(s)
- Matthew R. Steinhart
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
| | - Frances E. Cone
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
| | - Cathy Nguyen
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
| | - Thao D. Nguyen
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD
| | - Mary E. Pease
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
| | - Oliver Puk
- Institute of Developmental Genetics, Helmholtz Center, Munich, Germany
| | - Jochen Graw
- Institute of Developmental Genetics, Helmholtz Center, Munich, Germany
| | - Ericka N. Oglesby
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
| | - Harry A. Quigley
- Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD
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Cone FE, Steinhart MR, Oglesby EN, Kalesnykas G, Pease ME, Quigley HA. The effects of anesthesia, mouse strain and age on intraocular pressure and an improved murine model of experimental glaucoma. Exp Eye Res 2012; 99:27-35. [PMID: 22554836 DOI: 10.1016/j.exer.2012.04.006] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 04/03/2012] [Accepted: 04/17/2012] [Indexed: 01/08/2023]
Abstract
The purpose of this study was to improve a mouse model of chronic intraocular pressure (IOP) elevation utilizing microbead injection in two strains of mice and to assess the effect of age and anesthesia on measured IOP. We compared our previous model with two modified protocols for injecting polystyrene microbeads and viscoelastic material in CD1or C57BL/6 mice. The measured outcomes were degree of IOP elevation and production of axonal loss. The first new protocol was injection of 3 μL of equal volumes of 6 μm and 1 μm diameter beads, followed by 2 μL of viscoelastic (3+2). The second new protocol injected 4 μL of the two bead mixture, then 1 μL of viscoelastic (4+1). Both were compared to injection of 2 μL of 6 μm beads with 3 μL of viscoelastic (2+3). We also compared the effects of age and of two anesthetic regimens (intraperitoneal ketamine/xylazine/acepromazine versus isoflurane gas) on measured IOP in untreated eyes of both strains. IOP was 2mm Hg lower with intraperitoneal than with gas anesthesia in both strains (p=0.003, p<0.0001, t-test). IOP measurements were lower in untreated young (2 months) compared to older (10 months) C57BL/6 mice (p=0.001, t-test). In the experimental glaucoma mouse model, mean IOP and number of elevated IOP measurements were higher in newer protocols. Mean axon loss with the 4+1 protocol (all strains) was twice that of the 2+3 and 3+2 protocols (36% vs. 15% loss, p=0.0026, ANOVA), and mean axon loss in CD1 mice (21%) was greater than in C57BL/6 mice (13%) (p=0.047, ANOVA). Median axon loss in 4+1 protocol treated C57BL/6 mice expressing yellow fluorescent protein in 2% of retinal ganglion cells (RGCs) had greater median axon loss than C57BL/6 4+1 protocol treated mice (26% vs. 10%, p=0.03). The 4+1 protocol provided higher, more consistent IOP elevation and greater axonal loss. The effects of age, strain, and anesthesia on induced IOP elevation and axon damage must be considered in mouse experimental glaucoma research.
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Affiliation(s)
- Frances E Cone
- Glaucoma Center of Excellence, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Smith Building M002, 400 North Broadway Baltimore, MD 21287, USA.
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Vidal-Sanz M, Salinas-Navarro M, Nadal-Nicolás FM, Alarcón-Martínez L, Valiente-Soriano FJ, Miralles de Imperial J, Avilés-Trigueros M, Agudo-Barriuso M, Villegas-Pérez MP. Understanding glaucomatous damage: Anatomical and functional data from ocular hypertensive rodent retinas. Prog Retin Eye Res 2012; 31:1-27. [DOI: 10.1016/j.preteyeres.2011.08.001] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 08/23/2011] [Accepted: 08/24/2011] [Indexed: 12/24/2022]
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Chou TH, Kocaoglu OP, Borja D, Ruggeri M, Uhlhorn SR, Manns F, Porciatti V. Postnatal elongation of eye size in DBA/2J mice compared with C57BL/6J mice: in vivo analysis with whole-eye OCT. Invest Ophthalmol Vis Sci 2011; 52:3604-12. [PMID: 21372015 DOI: 10.1167/iovs.10-6340] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
PURPOSE To characterize postnatal changes in eye size in glaucomatous DBA/2J (D2) mice and in nonglaucomatous C57BL/6J mice (B6) in vivo by means of whole-eye optical coherence tomography (OCT). METHODS D2 (n = 32) and B6 (n = 36) mice were tested between 2 and 20 months of age in eight age bins. A custom time-domain OCT system with a center wavelength of 825 nm and an axial scan length of 7.1 mm produced axial A-scan interferograms at a rate of 20 A-lines/s with a resolution of 8 μm. Axial length (AL), corneal thickness (CT), anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and retinal thickness (RT) were measured in the optical axis and adjusted with corresponding refractive indices. Corneal curvature (CC) and IOP were also measured. RESULTS AL increased (P < 0.001) more in the D2 (21%) than in the B6 (9%) mice. There was an interaction effect (two-way ANOVA, P < 0.001) between age and strain for AL, CT, ACD, and VCD. In the D2 mice, the lens became dislocated posteriorly. Multiple regression analysis in the D2 mice revealed an independent effect of age and IOP (P ≤ 0.01) on axial length. CC steepened in the older D2 mice, whereas it flattened in the B6 mice. CONCLUSIONS In D2 mice, postnatal elongation of AL is larger than that in B6 mice and is associated with a greater increase in ACD and IOP, which seems to be a causal factor. The ease of use, short acquisition time, and noninvasiveness of whole-eye OCT make it suitable for routine use in longitudinal studies of mouse models.
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Affiliation(s)
- Tsung-Han Chou
- Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, Florida 33136, USA
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Ding C, Wang P, Tian N. Effect of general anesthetics on IOP in elevated IOP mouse model. Exp Eye Res 2011; 92:512-20. [PMID: 21457709 PMCID: PMC3116023 DOI: 10.1016/j.exer.2011.03.016] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 03/21/2011] [Accepted: 03/21/2011] [Indexed: 12/23/2022]
Abstract
Elevated intraocular pressure (IOP) is the best recognized risk factor for the pathogenesis of glaucoma and the extent of retinal ganglion cell (RGC) degeneration in glaucoma is closely correlated with the extent of IOP elevation. Therefore, accurately and reliably measuring IOP is critical in investigating the mechanism of pressure-induced RGC damage in glaucoma. However, IOP is measured under general anesthesia in most studies using mouse models and many anesthetics affect the IOP measurements in both human and animals. In the present study, we used a noninvasive approach to measure the IOP of mice with normal and elevated IOP. The approach used mice that were awake and mice that were under general anesthesia. Our results demonstrate that not only the behavioral training enables IOP measurement from conscious mice without using a restrainer, it also significantly improves the consistency and reliability of the IOP measurement. In addition, we provide a direct comparison between awake and anesthetized IOP measurements as a function of time after the induction of general anesthesia with several commonly used anesthetic agents. We found that all tested general anesthetics significantly altered the IOP measurements both in normal eyes and in those with elevated IOP. Therefore, we conclude that behavioral training of mice can provide an approach to measure awake IOP that does not require general anesthesia and thus produces reliable and consistent results.
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Affiliation(s)
- Chun Ding
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Hunan, China
- Department of Ophthalmology and Visual Science, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Ping Wang
- Department of Ophthalmology and Visual Science, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Ning Tian
- Department of Ophthalmology and Visual Science, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
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Salvetat ML, Zeppieri M, Miani F, Tosoni C, Parisi L, Brusini P. Comparison of iCare tonometer and Goldmann applanation tonometry in normal corneas and in eyes with automated lamellar and penetrating keratoplasty. Eye (Lond) 2011; 25:642-50. [PMID: 21436848 DOI: 10.1038/eye.2011.60] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
PURPOSE To compare intraocular pressure (IOP) measurements with Goldmann applanation tonometry (GAT) and iCare tonometry in normal and post-keratoplasty corneas and to assess the influence of central corneal thickness (CCT), corneal curvature (CC), and corneal astigmatism (CA) on IOP. METHODS This prospective cross-sectional study included one eye of 101 subjects with normal corneas (58 healthy subjects, 43 glaucoma); and 90 post-keratoplasty patients: 34 penetrating keratoplasties (PK); 20 automated-lamellar-therapeutic keratoplasties (ALTK); 19 Descemet-stripping-automated-endothelial keratoplasties (DSAEK); 17 edematous grafts. All subjects underwent GAT and iCare IOP measurements in random order, and CCT, CC, and CA evaluation. The Bland-Altman method and multivariate regression analysis were used to assess inter-tonometer agreement and the influence of CCT, CC, and CA on IOP. RESULTS iCare significantly underestimated IOP in all groups compared with GAT (GAT minus iCare of 3.5±3.5 mm Hg, P<0.001), but overestimated IOP in the edematous grafts (GAT minus iCare of -6.5±1.9 mm Hg, P<0.001). In normal corneas, both tonometer measurements were directly related to CCT values; iCare readings appeared inversely related to CC. There was no significant relationship between IOP and CCT, CC and CA in post-keratoplasty eyes, except between CC and iCare measurements for PK eyes. CONCLUSIONS The agreement between GAT and iCare was clinically acceptable in control, ALTK and DSAEK groups, and poor in PK and edematous grafts eyes. In normal corneas, GAT was significantly affected by CCT; iCare was influenced by CCT and CC. The iCare appeared less influenced by corneal edema when compared with GAT. High IOP readings taken with both tonometers in grafts should raise suspicion of true elevated IOP.
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Affiliation(s)
- M L Salvetat
- Department of Ophthalmology, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, S.O.C. Oculistica, piazzale S. Maria della Misericordia 15, Udine, Italy
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Quigley HA, Cone FE, Gelman SE, Yang Z, Son JL, Oglesby EN, Pease ME, Zack DJ. Lack of neuroprotection against experimental glaucoma in c-Jun N-terminal kinase 3 knockout mice. Exp Eye Res 2011; 92:299-305. [PMID: 21272576 DOI: 10.1016/j.exer.2011.01.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 12/21/2010] [Accepted: 01/18/2011] [Indexed: 01/09/2023]
Abstract
To determine if the absence of c-Jun N-terminal kinase 3 (JNK3) in the mouse retina would reduce retinal ganglion cell (RGC) loss in mice with experimental glaucoma. C57BL/6 mice underwent experimental intraocular pressure (IOP) elevation with a bead/viscoelastic injection into one eye. One-half of the mice were Jnk3 homozygous knockouts (KO) and were compared to wild type (WT) mice. IOP was measured under anesthesia with the TonoLab, axial length was measured post-mortem with calipers after inflation to 15mmHg, and RGC layer counts were performed on retinal whole mount images stained with DAPI, imaged by confocal microscopy, and counted by masked observers in an image analysis system. Axon counts were performed in optic nerve cross-sections by semi-automated image analysis. Both WT and Jnk3(-/-) mice had mean elevations of IOP of more than 50% after bead injection. Both groups underwent the expected axial globe elongation due to chronic IOP elevation. The absence of JNK3 in KO retina was demonstrated by Western blots. RGC layer neuron counts showed modest loss in both WT and Jnk3(-/-) animals; local differences by retinal eccentricity were detected, in each case indicating greater loss in KO animals than in WT. The baseline number of RGC layer cells in KO animals was 10% higher than in WT, but the number of optic nerve axons was identical in KO and WT controls. A slightly greater loss of RGC in Jnk3(-/-) mice compared to controls was detected in experimental mouse glaucoma by RGC layer counting and there was no protective effect shown in axon counts. Counts of RGC layer cells and optic nerve axons indicate that Jnk3(-/-) mice have an increased number of amacrine cells compared to WT controls.
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Affiliation(s)
- Harry A Quigley
- Glaucoma Research Laboratory, Wilmer Eye Institute, 600 North Wolfe Street, Johns Hopkins University School of Medicine, Baltimore, MD 21287-9205, USA.
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