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Kapeller LE, Cabble AG, Buckman PN, Harman CD, Jacobson AL, Lawrence FR, Komáromy AM. Validation of the eyeTelemed IOPvet indentation tonometer for use in dogs. Vet Ophthalmol 2024. [PMID: 38563215 DOI: 10.1111/vop.13215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/01/2024] [Accepted: 03/15/2024] [Indexed: 04/04/2024]
Abstract
OBJECTIVE To assess the accuracy of canine intraocular pressure (IOP) estimates from the eyeTelemed IOPvet indentation tonometer. ANIMALS STUDIED Part 1 included 54 eyes from 28 Beagle dogs-23 ADAMTS10-mutants with open-angle glaucoma and 5 normals. Part 2 involved five normal canine ex vivo globes. PROCEDURE Part 1 (in vivo) compared IOPvet estimates in normal and glaucomatous dogs to Reichert Tono-Vera® Vet rebound tonometry. The three IOPvet estimates were green (normal; <20 mmHg, according to the manufacturer), yellow (elevated; 20-30 mmHg), and red (high; >30 mmHg). In Part 2 (ex vivo), the pressure inside freshly enucleated normal canine eyes was progressively increased from 5 to 80 mmHg and compared to IOPvet estimates. Descriptive statistics compared IOPvet estimates to rebound tonometry and direct manometry, with the threshold from normal to glaucoma set at 30 mmHg. RESULTS In Part 1 (in vivo), normal pressures (≤30 mmHg) were mainly identified correctly as green or yellow-110 of 111 estimates, corresponding to a specificity of 99%. Only 16 of 125 affected estimates were correctly displayed in the >30-mmHg range; the remaining 109 showed ≤30 mmHg, corresponding to a sensitivity of 13%. In Part 2 (ex vivo), all normal pressures were correctly estimated with green, but 64 of 88 manometric IOPs >30 mmHg were falsely estimated as 20-30 mmHg. CONCLUSIONS The IOPvet is inaccurate in estimating canine IOP with a low sensitivity at identifying dogs with IOP > 30 mmHg. Canine-specific instrument revision is required to correctly identify elevated (yellow = 20-30 mmHg) and high (red >30 mmHg) IOPs.
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Affiliation(s)
- Lydia E Kapeller
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Ava G Cabble
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Phillip N Buckman
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Christine D Harman
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Amanda L Jacobson
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Frank R Lawrence
- Center for Statistical Training and Consulting, Michigan State University, East Lansing, Michigan, USA
| | - András M Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
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Raphtis VA, Sharma D, Wang S, Kim JY, Jacobson AL, Harman CD, Komáromy AM. Ocular pulse amplitude (OPA) in canine ADAMTS10-open-angle glaucoma ( ADAMTS10-OAG). Front Bioeng Biotechnol 2023; 11:1242166. [PMID: 38130820 PMCID: PMC10733518 DOI: 10.3389/fbioe.2023.1242166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023] Open
Abstract
Introduction: The role of ocular rigidity and biomechanics remains incompletely understood in glaucoma, including assessing an individual's sensitivity to intraocular pressure (IOP). In this regard, the clinical assessment of ocular biomechanics represents an important need. The purpose of this study was to determine a possible relationship between the G661R missense mutation in the ADAMTS10 gene and the ocular pulse amplitude (OPA), the difference between diastolic and systolic intraocular pressure (IOP), in a well-established canine model of open-angle glaucoma (OAG). Methods: Animals studied included 39 ADAMTS10-mutant dogs with different stages of OAG and 14 unaffected control male and female dogs between 6 months and 12 years (median: 3.2 years). Dogs were sedated intravenously with butorphanol tartrate and midazolam HCl, and their IOPs were measured with the Icare® Tonovet rebound tonometer. The Reichert Model 30™ Pneumotonometer was used to measure OPA. Central corneal thickness (CCT) was measured via Accutome® PachPen, and A-scan biometry was assessed with DGH Technology Scanmate. All outcome measures of left and right eyes were averaged for each dog. Data analysis was conducted with ANOVA, ANCOVA, and regression models. Results: ADAMTS10-OAG-affected dogs displayed a greater IOP of 23.0 ± 7.0 mmHg (mean ± SD) compared to 15.3 ± 3.6 mmHg in normal dogs (p < 0.0001). Mutant dogs had a significantly lower OPA of 4.1 ± 2.0 mmHg compared to 6.5 ± 2.8 mmHg of normal dogs (p < 0.01). There was no significant age effect, but OPA was correlated with IOP in ADAMTS10-mutant dogs. Conclusion: The lower OPA in ADAMTS10-mutant dogs corresponds to the previously documented weaker and biochemically distinct posterior sclera, but a direct relationship remains to be confirmed. The OPA may be a valuable clinical tool to assess ocular stiffness and an individual's susceptibility to IOP elevation.
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Affiliation(s)
- Vanessa A. Raphtis
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Dhruv Sharma
- Center for Statistical Training and Consulting, Michigan State University, East Lansing, MI, United States
| | - Sichao Wang
- Center for Statistical Training and Consulting, Michigan State University, East Lansing, MI, United States
| | - Jae Y. Kim
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Amanda L. Jacobson
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - Christine D. Harman
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, United States
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He M, Rong R, Ji D, Xia X. From Bench to Bed: The Current Genome Editing Therapies for Glaucoma. Front Cell Dev Biol 2022; 10:879957. [PMID: 35652098 PMCID: PMC9149310 DOI: 10.3389/fcell.2022.879957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 04/25/2022] [Indexed: 11/20/2022] Open
Abstract
Glaucoma is a group of optic neuropathies featured by degeneration of retinal ganglion cells and loss of their axons in the optic nerve. The only currently approved therapies focus on lowering intraocular pressure with medication and surgery. Over the previous few decades, technological advances and research progress regarding pathogenesis has brought glaucomatous gene therapy to the forefront. In this review, we discuss the three current genome editing methods and potential disease mechanisms of glaucoma. We further summarize different genome editing strategies that are being developed to target a number of glaucoma-related genes and pathways from four aspects including strategies to lower intraocular pressure, neuroprotection, RGC and optic nerve neuro-regeneration, and other strategies. In summary, genome therapy is a promising therapy for treating patients with glaucoma and has great potential to be widely applied in clinical practice.
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Affiliation(s)
- Meihui He
- Eye Center of Xiangya Hospital, Central South University, Changsha, China.,Hunan Key Laboratory of Ophthalmology, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Rong Rong
- Eye Center of Xiangya Hospital, Central South University, Changsha, China.,Hunan Key Laboratory of Ophthalmology, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Dan Ji
- Eye Center of Xiangya Hospital, Central South University, Changsha, China.,Hunan Key Laboratory of Ophthalmology, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaobo Xia
- Eye Center of Xiangya Hospital, Central South University, Changsha, China.,Hunan Key Laboratory of Ophthalmology, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
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Mischi E, Soukup P, Harman CD, Oikawa K, Kowalska ME, Hartnack S, McLellan GJ, Komáromy AM, Pot SA. Outer retinal thickness and visibility of the choriocapillaris in four distinct retinal regions imaged with spectral domain optical coherence tomography in dogs and cats. Vet Ophthalmol 2022; 25 Suppl 1:122-135. [PMID: 35611616 PMCID: PMC9246961 DOI: 10.1111/vop.12989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 04/04/2022] [Accepted: 04/04/2022] [Indexed: 11/29/2022]
Abstract
PURPOSE To evaluate the outer retinal band thickness and choriocapillaris (CC) visibility in four distinct retinal regions in dogs and cats imaged with spectral domain optical coherence tomography (SD-OCT). To attempt delineation of a fovea-like region in canine and feline SD-OCT scans, aided by the identification of outer retinal thickness differences between retinal regions. METHODS Spectralis® HRA + OCT SD-OCT scans from healthy, anesthetized dogs (n = 10) and cats (n = 12) were analyzed. Scanlines on which the CC was identifiable were counted and CC visibility was scored. Outer nuclear layer (ONL) thickness and the distances from external limiting membrane (ELM) to retinal pigment epithelium/Bruch's membrane complex (RPE/BM) and ELM to CC were measured in the area centralis (AC), a visually identified fovea-like region, and in regions superior and inferior to the optic nerve head (ONH). Measurements were analyzed using a multilevel regression. RESULTS The CC was visible in over 90% of scanlines from dogs and cats. The ONL was consistently thinnest in the fovea-like region. The outer retina (ELM-RPE and ELM-CC) was thickest within the AC compared with superior and inferior to the ONH in dogs and cats (p < .001 for all comparisons). CONCLUSIONS The CC appears a valid, albeit less than ideal outer retinal boundary marker in tapetal species. The AC can be objectively differentiated from the surrounding retina on SD-OCT images of dogs and cats; a fovea-like region was identified in dogs and its presence was suggested in cats. These findings allow targeted imaging and image evaluation of these regions of retinal specialization.
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Affiliation(s)
- Elisa Mischi
- Ophthalmology Section, Equine Department, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Petr Soukup
- Ophthalmology Section, Equine Department, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Christine D. Harman
- Department of Small Animal Clinical Sciences, College of Veterinary MedicineMichigan State UniversityEast LansingMichiganUSA
| | - Kazuya Oikawa
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public HealthUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - Malwina E. Kowalska
- Ophthalmology Section, Equine Department, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
- Section of Epidemiology, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Sonja Hartnack
- Section of Epidemiology, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
| | - Gillian J. McLellan
- Department of Ophthalmology and Visual Sciences, School of Medicine and Public HealthUniversity of Wisconsin‐MadisonMadisonWisconsinUSA
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary MedicineMichigan State UniversityEast LansingMichiganUSA
| | - Simon A. Pot
- Ophthalmology Section, Equine Department, Vetsuisse FacultyUniversity of ZurichZurichSwitzerland
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Nagao RJ, Marcu R, Shin YJ, Lih D, Xue J, Arang N, Wei L, Akilesh S, Kaushansky A, Himmelfarb J, Zheng Y. Cyclosporine Induces Fenestra-Associated Injury in Human Renal Microvessels In Vitro. ACS Biomater Sci Eng 2021; 8:196-207. [DOI: 10.1021/acsbiomaterials.1c00986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ryan J. Nagao
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
| | - Raluca Marcu
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
- Kidney Research Institute, University of Washington, Seattle, Washington 98109, United States
| | - Yu Jung Shin
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
| | - Daniel Lih
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
- Kidney Research Institute, University of Washington, Seattle, Washington 98109, United States
| | - Jun Xue
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
| | - Nadia Arang
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98101, United States
| | - Ling Wei
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98101, United States
| | - Shreeram Akilesh
- Kidney Research Institute, University of Washington, Seattle, Washington 98109, United States
- Department of Pathology, University of Washington, Seattle, Washington 98195, United States
| | - Alexis Kaushansky
- Center for Global Infectious Disease Research, Seattle Children’s Research Institute, Seattle, Washington 98101, United States
- Department of Pediatrics, University of Washington, Seattle, Washington 98195, United States
| | - Jonathan Himmelfarb
- Kidney Research Institute, University of Washington, Seattle, Washington 98109, United States
- Department of Medicine, University of Washington, Seattle, Washington 98109, United States
| | - Ying Zheng
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, United States
- Kidney Research Institute, University of Washington, Seattle, Washington 98109, United States
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington 98109, United States
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Burn JB, Huang AS, Weber A, Komáromy AM, Pirie CG. Aqueous angiography in pre-glaucomatous and glaucomatous ADAMTS10-mutant canine eyes: A pilot study. Vet Ophthalmol 2021; 25 Suppl 1:72-83. [PMID: 34724299 PMCID: PMC9056585 DOI: 10.1111/vop.12938] [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: 02/22/2021] [Revised: 08/30/2021] [Accepted: 09/06/2021] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate intravenous scleral and intracameral aqueous angiography in normotensive (n = 4) and hypertensive glaucomatous (n = 6) ADAMTS10-mutant canine eyes. ANIMALS STUDIED Ten ADAMTS10-mutant dogs were used in this study. PROCEDURES Dogs were sedated and one eye from each dog underwent scleral angiography following intravenous injection of 0.25% indocyanine green (ICG). After a 24-h recovery period, the same eye underwent aqueous angiography via intracameral administration of ICG. Imaging of identical scleral sectors from the same eye was performed using a Heidelberg Spectralis® Confocal Scanning Laser Ophthalmoscope. Intrascleral vessel depth and lumen diameters were measured using Heidelberg Spectralis® optical coherence tomography and computer software. RESULTS Scleral angiography permitted visualization of vascular components associated with conventional aqueous humor outflow pathways with an average time from injection to fluorescence of 35.8 ± 10.6 s (mean ± SD). Two normotensive eyes (2/10;20%) demonstrated turbulent dye movement, while 4 hypertensive eyes (4/10;40%) exhibited laminar flow. Aqueous angiography demonstrated dye fluorescence within the post-trabecular conventional aqueous humor outflow pathways in all 10 eyes at 34.3 ± 11.0 s post-injection. Sectoral and dynamic outflow patterns were observed primarily within the superotemporal sector in nine eyes (9/10; 90%). Seven eyes (7/10; 70%) demonstrated pulsatile dye movement and five eyes (5/10; 50%) exhibited laminar flow. The degree of laminar movement of dye was greatest in hypertensive eyes. Vessel lumen diameters measured 133.85 ± 28.36 µm and 161.18 ± 6.02 µm in hypertensive and normotensive eyes, respectively. CONCLUSIONS Aqueous angiography allowed for visualization of fluorescent dye in the superotemporal sclera. Laminar flow and smaller lumen vessels were observed mainly in hypertensive eyes.
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Affiliation(s)
| | | | - Arthur Weber
- Michigan State University, East Lansing, Michigan, USA
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Yun S, Lee D, Kang S, Kim DW, Kim Y, Cho JY, Seo K. Proteomic analysis of aqueous humor in canine primary angle-closure glaucoma in American Cocker Spaniel dogs. Vet Ophthalmol 2021; 24:520-532. [PMID: 34558166 DOI: 10.1111/vop.12937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/02/2021] [Accepted: 09/06/2021] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To analyze proteomic profiles of the aqueous humor (AH) of canines with primary angle-closure glaucoma (PACG) and identify associated protein alterations. ANIMALS STUDIED Six American Cocker Spaniels with PACG and six American Cocker Spaniels without ocular diseases. METHODS Aqueous humor samples were collected from six American Cocker Spaniels with PACG at Seoul National University, VMTH, and six healthy Cocker Spaniels without ocular disease at Irion Animal Hospital. For the PACG group, AH samples were obtained by anterior chamber paracentesis prior to glaucoma treatment. For the AH control group, AH samples were collected from patients anesthetized for other reasons. Total AH protein concentration was determined by the bicinchoninic acid (BCA) assay. AH protein samples were quantified by liquid chromatography-mass spectrometry (LC-MS/MS). Raw MS spectra were processed using MaxQuant software 30, and the Gene Ontology (GO) enrichment analysis was performed using ClueGO. RESULTS The AH protein concentration in the PACG group (10.49 ± 17.98 µg/µl) was significantly higher than that of the control group (0.45 ± 0.11 µg/µl; p < .05). A total of 758 proteins were identified in the AH. Several proteins both significantly increased (n = 69) and decreased (n = 252) in the PACG group compared to those in the control group. GO enrichment analysis showed that the "response to wounding," "negative regulation of endopeptidase activity," and "cell growth" pathways were the most enriched terms in the PACG group compared to the control group. The top 5 proteins that were significantly increased in the AH of the PACG group were secreted phosphoprotein 1 (SPP1), peptidoglycan recognition proteins 2 (PGLYRP2), tyrosine 3-monooxygenase (YWHAE), maltase-glucoamylase (MGAM), and vimentin (VIM). CONCLUSIONS Gene Ontology enrichment analysis using the proteomic data showed that proteins and pathways related to inflammation were significantly upregulated in the various stage of PACG. Proteomic analysis of the AH from the PACG may provide valuable insights into PACG pathogenesis.
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Affiliation(s)
- Seongjin Yun
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea.,Irion animal hospital, Seoul, Korea
| | - Dabin Lee
- Department of Veterinary Biochemistry, BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Seonmi Kang
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Dong Wook Kim
- Department of Veterinary Biochemistry, BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Youngsam Kim
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
| | - Je-Yoel Cho
- Department of Veterinary Biochemistry, BK21 PLUS Program for Creative Veterinary Science Research and Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Kangmoon Seo
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul, Korea
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Park SA, Komáromy AM. Biomechanics of the optic nerve head and sclera in canine glaucoma: A brief review. Vet Ophthalmol 2021; 24:316-325. [PMID: 34402566 DOI: 10.1111/vop.12923] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 06/04/2021] [Accepted: 07/25/2021] [Indexed: 01/17/2023]
Abstract
Glaucoma is a leading cause of irreversible blindness, a progressive optic neuropathy with retinal ganglion cell (RGC) death beginning in the optic nerve head (ONH). A primary risk factor for developing glaucoma is elevated intraocular pressure (IOP). Reducing IOP is the only treatment proven to be effective at delaying disease progression. Nevertheless, even when patients have their IOP reduced, the majority of them continue to lose vision. There are, in both humans and dogs, significant interindividual variabilities in susceptibilities to IOP-induced optic nerve damage. Vision loss progresses much more slowly in Beagles with open-angle glaucoma (OAG) caused by ADAMTS10 mutation. This can be attributed to the mutation-related altered ocular biomechanical properties. The principal site of optic nerve (ON) damage in glaucoma is the ONH. It is suggested that the biomechanical properties of the ONH and the surrounding peripapillary sclera (PPS) contribute to glaucoma development and progression. As far as the beneficial biomechanical properties of the ONH and PPS for a decreased susceptibility and slow progression of glaucoma, data are inconsistent and conflicting. Recent biomechanical studies on beagles with ADAMTS10 mutation demonstrated that the mutant dogs have mechanically weak posterior sclera. This weakness was associated with a reduced collagen density and a lower proportion of insoluble collagen. These changes, observed before glaucoma development, were considered intrinsic characteristics caused by the mutation rather than a secondary effect of IOP elevation. Further studies of ADAMTS10-OAG may elucidate the effects of altered biomechanical properties of ONH and PPS in determining the glaucoma progression.
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Affiliation(s)
- Shin Ae Park
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, USA
| | - András M Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
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Corneal Biomechanical Changes Caused by Acute Elevation of IOP in Eyes with and without Glaucoma. Optom Vis Sci 2021; 98:367-373. [PMID: 33828042 DOI: 10.1097/opx.0000000000001668] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
SIGNIFICANCE Although corneal biomechanical parameters are well linked with glaucoma, their clinical utility has not yet been fully elucidated. This study was designed to provide unique evidence about the dynamic nature of corneal biomechanical parameters and their potential prognostic ability for glaucoma. PURPOSE This study aimed to evaluate the effect of acute intraocular pressure (IOP) elevation on corneal hysteresis (CH) and corneal resistance factor (CRF) and the associations of these biomechanical parameters with glaucomatous disease. METHODS Subjects participating in a prospective, longitudinal glaucoma research study had CH and CRF measured before and during ophthalmodynamometry during visits in the years 2011 to 2012. All participants were diagnosed with primary open-angle glaucoma, ocular hypertension, glaucoma suspect, or normal eyes and had a minimum of 3 years of study participation with at least five reliable visual field (VF) tests. Changes in CH, CRF, and IOP induced by ophthalmodynamometry were compared between diagnostic groups and evaluated for relationships with existing and future glaucomatous VF loss. RESULTS In 248 eyes of 248 subjects followed up for 7.7 ± 2.3 years, ophthalmodynamometry induced a mean IOP increase from 15.1 to 29.9 mmHg, causing a mean 34 ± 28% increase in CRF and 21 ± 25% decrease in CH. Magnitude of CH change did not differ between diagnostic groups or between eyes that did (n = 20) and did not (n = 95) develop new VF loss during the study period, nor was it related to rate of future VF progression. CONCLUSIONS Ophthalmodynamometry-induced IOP elevation resulted in significant acute changes in CH and CRF in this study; this suggests accounting for IOP may be important in clinical interpretation of these parameters. However, because the degree of CH change was not related to glaucoma or its progression, acute changes in CH and CRF do not seem to have a prognostic value for glaucoma.
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Komáromy AM, Koehl KL, Park SA. Looking into the future: Gene and cell therapies for glaucoma. Vet Ophthalmol 2021; 24 Suppl 1:16-33. [PMID: 33411993 PMCID: PMC7979454 DOI: 10.1111/vop.12858] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 12/21/2020] [Indexed: 12/17/2022]
Abstract
Glaucoma is a complex group of optic neuropathies that affects both humans and animals. Intraocular pressure (IOP) elevation is a major risk factor that results in the loss of retinal ganglion cells (RGCs) and their axons. Currently, lowering IOP by medical and surgical methods is the only approved treatment for primary glaucoma, but there is no cure, and vision loss often progresses despite therapy. Recent technologic advances provide us with a better understanding of disease mechanisms and risk factors; this will permit earlier diagnosis of glaucoma and initiation of therapy sooner and more effectively. Gene and cell therapies are well suited to target these mechanisms specifically with the potential to achieve a lasting therapeutic effect. Much progress has been made in laboratory settings to develop these novel therapies for the eye. Gene and cell therapies have already been translated into clinical application for some inherited retinal dystrophies and age-related macular degeneration (AMD). Except for the intravitreal application of ciliary neurotrophic factor (CNTF) by encapsulated cell technology for RGC neuroprotection, there has been no other clinical translation of gene and cell therapies for glaucoma so far. Possible application of gene and cell therapies consists of long-term IOP control via increased aqueous humor drainage, including inhibition of fibrosis following filtration surgery, RGC neuroprotection and neuroregeneration, modification of ocular biomechanics for improved IOP tolerance, and inhibition of inflammation and neovascularization to prevent the development of some forms of secondary glaucoma.
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Affiliation(s)
- András M. Komáromy
- College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
| | - Kristin L. Koehl
- College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
| | - Shin Ae Park
- College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA
- College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
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11
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Graham KL, Diefenbach E, McCowan CI, White AJR. A technique for shotgun proteomic analysis of the precorneal tear film in dogs with naturally occurring primary glaucoma. Vet Ophthalmol 2020; 24 Suppl 1:131-145. [PMID: 32364655 DOI: 10.1111/vop.12765] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 03/27/2020] [Accepted: 03/31/2020] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To introduce a protocol for the characterization of protein patterns in tears of dogs with primary angle closure glaucoma (PACG) and primary open-angle glaucoma (POAG). ANIMALS Nineteen dogs (25 eyes). METHODS Tear samples were collected using a Schirmer tear strip, from dogs with PACG (PACG-affected eyes, n = 8; unaffected eyes predisposed to PACG, n = 7), POAG (n = 4), and healthy controls (n = 6). Protein precipitation and trypsin digestion were performed for analyses via liquid chromatography-tandem mass spectrometry. Proteins were identified using the SwissProt protein sequence database. Relative protein expression in 17 eyes (15 dogs) was evaluated using Proteome Discoverer 2.0. Pathway analyses were performed to investigate molecular mechanisms associated with primary glaucoma. RESULTS Unique peptides were identified in 505 proteins, with Major allergen Can f 1 and albumin identified with high confidence. Proteins unique to tears from diseased eyes (PACG: n = 7; POAG: n = 14) were identified. Nucleoside diphosphate was unique to tears in PACG eyes naïve to therapy, while retinal binding protein and NSFL1 cofactor p47 were unique to medicated PACG eyes. Relative expression of 34 proteins differed between disease states. Pathway analyses identified that the 'inflammatory response' was among the top disease/disorders in dogs with primary glaucoma (PACG and POAG) but not in healthy controls. CONCLUSION Tear samples suitable for mass spectrometry were readily obtained from pet dogs without needing specialized equipment. Further studies to validate the findings and explore potential candidate biomarkers for early disease detection and potential therapeutic targets are indicated.
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Affiliation(s)
- Kathleen L Graham
- Clinical Ophthalmology and Eye Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Eve Diefenbach
- Westmead Proteomics Facility, Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Christina I McCowan
- University of Melbourne Veterinary Hospital, University of Melbourne, Melbourne, Vic, Australia.,Department of Jobs, Precincts and Regions, Victoria State Government, Melbourne, Vic, Australia
| | - Andrew J R White
- Clinical Ophthalmology and Eye Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.,Centre of Vision Research, Westmead Institute for Medical Research, Westmead, NSW, Australia
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Kim JH, Kwon TR, Lee SE, Jang YN, Han HS, Mun SK, Kim BJ. Comparative Evaluation of the Effectiveness of Novel Hyaluronic Acid-Polynucleotide Complex Dermal Filler. Sci Rep 2020; 10:5127. [PMID: 32198443 PMCID: PMC7083941 DOI: 10.1038/s41598-020-61952-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 02/18/2020] [Indexed: 11/08/2022] Open
Abstract
HA (Hyaluronic acid) filler, the most commonly used dermal filler, causes several side effects. HA-PN (Hyaluronic acid-Polynucleotide), a new composite filler, has excellent biocompatibility and induces tissue regeneration. In this study, we compare the efficacies and safety profiles of these fillers. The characteristics of HA and HA-PN fillers were compared using scanning electron microscopy and rheometry. No morphological difference was noted between the fillers. However, the latter had higher viscosity and elasticity values. The HA-PN filler induced higher cell migration than the HA filler in a wound healing assay. It was also found to stimulate better collagen synthesis in human and mouse fibroblasts. The HA and HA-PN fillers were injected into SKH1 hairless mice to determine changes in their volume for up to 24 weeks. Increased cell migration and collagen synthesis were observed in mice injected with the HA-PN complex filler. Although the safety and durability of the HA and HA-PN fillers were similar, the latter induced a lower transient receptor potential vanilloid 4 expression and caused less stimulation upon injection. In conclusion, HA-PN complex fillers can stimulate fibroblast growth and facilitate volume growth and skin regeneration.
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Affiliation(s)
- Jong Hwan Kim
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea
| | - Tae-Rin Kwon
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea
| | - Sung Eun Lee
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea
- Department of Medicine, Graduate School, Chung-Ang University, Seoul, Korea
| | - Yoo Na Jang
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea
- Department of Medicine, Graduate School, Chung-Ang University, Seoul, Korea
| | - Hye Sung Han
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea
- Department of Medicine, Graduate School, Chung-Ang University, Seoul, Korea
| | - Seog Kyun Mun
- Department of Otorhinolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, Seoul, Korea
| | - Beom Joon Kim
- Department of Dermatology, Chung-Ang University College of Medicine, Seoul, Korea.
- Department of Medicine, Graduate School, Chung-Ang University, Seoul, Korea.
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13
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Komáromy AM, Bras D, Esson DW, Fellman RL, Grozdanic SD, Kagemann L, Miller PE, Moroi SE, Plummer CE, Sapienza JS, Storey ES, Teixeira LB, Toris CB, Webb TR. The future of canine glaucoma therapy. Vet Ophthalmol 2019; 22:726-740. [PMID: 31106969 PMCID: PMC6744300 DOI: 10.1111/vop.12678] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 04/05/2019] [Accepted: 04/15/2019] [Indexed: 02/06/2023]
Abstract
Canine glaucoma is a group of disorders that are generally associated with increased intraocular pressure (IOP) resulting in a characteristic optic neuropathy. Glaucoma is a leading cause of irreversible vision loss in dogs and may be either primary or secondary. Despite the growing spectrum of medical and surgical therapies, there is no cure, and many affected dogs go blind. Often eyes are enucleated because of painfully high, uncontrollable IOP. While progressive vision loss due to primary glaucoma is considered preventable in some humans, this is mostly not true for dogs. There is an urgent need for more effective, affordable treatment options. Because newly developed glaucoma medications are emerging at a very slow rate and may not be effective in dogs, work toward improving surgical options may be the most rewarding approach in the near term. This Viewpoint Article summarizes the discussions and recommended research strategies of both a Think Tank and a Consortium focused on the development of more effective therapies for canine glaucoma; both were organized and funded by the American College of Veterinary Ophthalmologists Vision for Animals Foundation (ACVO-VAF). The recommendations consist of (a) better understanding of disease mechanisms, (b) early glaucoma diagnosis and disease staging, (c) optimization of IOP-lowering medical treatment, (d) new surgical therapies to control IOP, and (e) novel treatment strategies, such as gene and stem cell therapies, neuroprotection, and neuroregeneration. In order to address these needs, increases in research funding specifically focused on canine glaucoma are necessary.
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Affiliation(s)
- András M Komáromy
- College of Veterinary Medicine, Michigan State University, East Lansing, Michigan
| | - Dineli Bras
- Centro de Especialistas Veterinarios de Puerto Rico, San Juan, Puerto Rico
| | | | | | | | - Larry Kagemann
- U.S. Food and Drug Administration, Silver Spring, Maryland.,New York University School of Medicine, New York, New York.,Department of Ophthalmology, School of Medicine, University of Maryland, Baltimore, Maryland
| | - Paul E Miller
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Sayoko E Moroi
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan
| | - Caryn E Plummer
- College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | | | - Eric S Storey
- South Atlanta Veterinary Emergency & Specialty, Fayetteville, Georgia
| | - Leandro B Teixeira
- School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin
| | - Carol B Toris
- Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska
| | - Terah R Webb
- MedVet Medical & Cancer Centers for Pets, Worthington, Ohio
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14
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Oliver JAC, Rustidge S, Pettitt L, Jenkins CA, Farias FHG, Giuliano EA, Mellersh CS. Evaluation of ADAMTS17 in Chinese Shar-Pei with primary open-angle glaucoma, primary lens luxation, or both. Am J Vet Res 2018; 79:98-106. [DOI: 10.2460/ajvr.79.1.98] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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Jia X, Yu J, Liao SH, Duan XC. Biomechanics of the sclera and effects on intraocular pressure. Int J Ophthalmol 2016; 9:1824-1831. [PMID: 28003987 DOI: 10.18240/ijo.2016.12.21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/03/2016] [Indexed: 11/23/2022] Open
Abstract
Accumulating evidence indicates that glaucoma is a multifactorial neurodegenerative disease characterized by the loss of retinal ganglion cells (RGC), resulting in gradual and progressive permanent loss of vision. Reducing intraocular pressure (IOP) remains the only proven method for preventing and delaying the progression of glaucomatous visual impairment. However, the specific role of IOP in optic nerve injury remains controversial, and little is known about the biomechanical mechanism by which elevated IOP leads to the loss of RGC. Published studies suggest that the biomechanical properties of the sclera and scleral lamina cribrosa determine the biomechanical changes of optic nerve head, and play an important role in the pathologic process of loss of RGC and optic nerve damage. This review focuses on the current understanding of biomechanics of sclera in glaucoma and provides an overview of the possible interactions between the sclera and IOP. Treatments and interventions aimed at the sclera are also discussed.
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Affiliation(s)
- Xu Jia
- Department of Ophthalmology, the Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Juan Yu
- Department of Ophthalmology, the First Hospital of Hunan University of Chinese Medicine, Changsha 410011, Hunan Province, China
| | - Sheng-Hui Liao
- School of Information Science and Engineering, Central South University, Changsha 410011, Hunan Province, China
| | - Xuan-Chu Duan
- Department of Ophthalmology, the Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
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16
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Palko JR, Morris HJ, Pan X, Harman CD, Koehl KL, Gelatt KN, Plummer CE, Komáromy AM, Liu J. Influence of Age on Ocular Biomechanical Properties in a Canine Glaucoma Model with ADAMTS10 Mutation. PLoS One 2016; 11:e0156466. [PMID: 27271467 PMCID: PMC4894564 DOI: 10.1371/journal.pone.0156466] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 05/13/2016] [Indexed: 11/29/2022] Open
Abstract
Soft tissue often displays marked age-associated stiffening. This study aims to investigate how age affects scleral biomechanical properties in a canine glaucoma model with ADAMTS10 mutation, whose extracellular matrix is concomitantly influenced by the mutation and an increased mechanical load from an early age. Biomechanical data was acquired from ADAMTS10-mutant dogs (n = 10, 21 to 131 months) and normal dogs (n = 5, 69 to 113 months). Infusion testing was first performed in the whole globes to measure ocular rigidity. After infusion experiments, the corneas were immediately trephined to prepare scleral shells that were mounted on a pressurization chamber to measure strains in the posterior sclera using an inflation testing protocol. Dynamic viscoelastic mechanical testing was then performed on dissected posterior scleral strips and the data were combined with those reported earlier by our group from the same animal model (Palko et al, IOVS 2013). The association between age and scleral biomechanical properties was evaluated using multivariate linear regression. The relationships between scleral properties and the mean and last measured intraocular pressure (IOP) were also evaluated. Our results showed that age was positively associated with complex modulus (p<0.001) and negatively associated with loss tangent (p<0.001) in both the affected and the normal groups, suggesting an increased stiffness and decreased mechanical damping with age. The regression slopes were not different between the groups, although the complex modulus was significantly lower in the affected group (p = 0.041). The posterior circumferential tangential strain was negatively correlated with complex modulus (R = -0.744, p = 0.006) showing consistent mechanical evaluation between the testing methods. Normalized ocular rigidity was negatively correlated with the last IOP in the affected group (p = 0.003). Despite a mutation that affects the extracellular matrix and a chronic IOP elevation in the affected dogs, age-associated scleral stiffening and loss of mechanical damping were still prominent and had a similar rate of change as in the normal dogs.
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Affiliation(s)
- Joel R. Palko
- Department of Biomedical Engineering, Ohio State University, Columbus, Ohio, United States of America
- Department of Ophthalmology, Washington University, St. Louis, Missouri, United States of America
| | - Hugh J. Morris
- Department of Biomedical Engineering, Ohio State University, Columbus, Ohio, United States of America
| | - Xueliang Pan
- Center for Biostatistics, Ohio State University, Columbus, OH, United States of America
| | - Christine D. Harman
- Department of Small Animal Clinical Sciences, Michigan State University, Lansing, Michigan, United States of America
| | - Kristin L. Koehl
- Department of Small Animal Clinical Sciences, Michigan State University, Lansing, Michigan, United States of America
| | - Kirk N. Gelatt
- Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, United States of America
| | - Caryn E. Plummer
- Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, United States of America
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, Michigan State University, Lansing, Michigan, United States of America
- Department of Small Animal Clinical Sciences, University of Florida, Gainesville, Florida, United States of America
- Department of Clinical Studies, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail: (JL); (AMK)
| | - Jun Liu
- Department of Biomedical Engineering, Ohio State University, Columbus, Ohio, United States of America
- Department of Ophthalmology, Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (JL); (AMK)
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17
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Boote C, Palko JR, Sorensen T, Mohammadvali A, Elsheikh A, Komáromy AM, Pan X, Liu J. Changes in posterior scleral collagen microstructure in canine eyes with an ADAMTS10 mutation. Mol Vis 2016; 22:503-17. [PMID: 27212875 PMCID: PMC4873561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 05/15/2016] [Indexed: 11/25/2022] Open
Abstract
PURPOSE We aimed to characterize alterations in the posterior scleral collagen microstructure before detectable disease onset in a canine model of open-angle glaucoma caused by an ADAMTS10 mutation. METHODS Collagen orientation, anisotropy degree (proportion of preferentially aligned collagen), and relative density were measured at 0.4 mm spatial resolution using synchrotron wide-angle X-ray scattering. For statistical evaluation of structure parameters, regional averages of the peripapillary and mid-posterior sclera were compared between ADAMTS10 mutant (affected) dogs (n = 3) and age-matched (carrier) controls (n = 3). RESULTS No marked differences in the general pattern of preferential collagen fibril orientation were noted between the control and affected dogs. The peripapillary sclera of all specimens featured strongly aligned circumferential collagen ringing the optic nerve head. Collagen anisotropy was significantly reduced in the mid-posterior sclera of the affected dogs (carrier: 0.27±0.11; affected: 0.24±0.10; p = 0.032) but was not statistically significantly different in the peripapillary sclera (carrier: 0.46±0.15; affected: 0.45±0.17; p = 0.68). Collagen density was statistically significantly reduced in the affected dogs for the mid-posterior sclera (carrier: 28.1±9.14; affected: 18.3±5.12; p<0.0001) and the peripapillary sclera (carrier: 34.6±9.34; affected: 21.1±6.97; p = 0.0002). CONCLUSIONS Significant alterations in the posterior scleral collagen microstructure are present before the onset of clinical glaucoma in ADAMTS10 mutant dogs. A reduction in fibrous collagen density is likely an important contributory factor in the previously reported mechanical weakening of the sclera in this model. Baseline scleral abnormalities have the potential to interact with intraocular pressure (IOP) elevations in determining the course of glaucoma progression in animal models of the disease, and potentially in human glaucoma.
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Affiliation(s)
- Craig Boote
- Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Joel R. Palko
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH
| | - Thomas Sorensen
- Diamond Light Source, Harwell Science and Innovation Campus, Harwell, UK
| | | | - Ahmed Elsheikh
- School of Engineering, University of Liverpool, Liverpool, UK,NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, UK
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, Michigan State University, East Lansing, MI,Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA
| | - Xueliang Pan
- Center for Biostatistics, Department of Biomedical Informatics, The Ohio State University, Columbus, OH
| | - Jun Liu
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH
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18
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Nguyen TD, Ethier CR. Biomechanical assessment in models of glaucomatous optic neuropathy. Exp Eye Res 2015; 141:125-38. [PMID: 26115620 PMCID: PMC4628840 DOI: 10.1016/j.exer.2015.05.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 05/20/2015] [Accepted: 05/31/2015] [Indexed: 01/26/2023]
Abstract
The biomechanical environment within the eye is of interest in both the regulation of intraocular pressure and the loss of retinal ganglion cell axons in glaucomatous optic neuropathy. Unfortunately, this environment is complex and difficult to determine. Here we provide a brief introduction to basic concepts of mechanics (stress, strain, constitutive relationships) as applied to the eye, and then describe a variety of experimental and computational approaches used to study ocular biomechanics. These include finite element modeling, direct experimental measurements of tissue displacements using optical and other techniques, direct experimental measurement of tissue microstructure, and combinations thereof. Thanks to notable technical and conceptual advances in all of these areas, we are slowly gaining a better understanding of how tissue biomechanical properties in both the anterior and posterior segments may influence the development of, and risk for, glaucomatous optic neuropathy. Although many challenging research questions remain unanswered, the potential of this body of work is exciting; projects underway include the coupling of clinical imaging with biomechanical modeling to create new diagnostic tools, development of IOP control strategies based on improved understanding the mechanobiology of the outflow tract, and attempts to develop novel biomechanically-based therapeutic strategies for preservation of vision in glaucoma.
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Affiliation(s)
- Thao D Nguyen
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - C Ross Ethier
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, USA; Department of Mechanical Engineering, Georgia Institute of Technology, USA; Institute of Biosciences and Bioengineering, Georgia Institute of Technology, USA; Department of Ophthalmology, Emory University, USA.
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19
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Oliver JAC, Forman OP, Pettitt L, Mellersh CS. Two Independent Mutations in ADAMTS17 Are Associated with Primary Open Angle Glaucoma in the Basset Hound and Basset Fauve de Bretagne Breeds of Dog. PLoS One 2015; 10:e0140436. [PMID: 26474315 PMCID: PMC4608710 DOI: 10.1371/journal.pone.0140436] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/25/2015] [Indexed: 02/02/2023] Open
Abstract
Purpose Mutations in ADAMTS10 (CFA20) have previously been associated with primary open angle glaucoma (POAG) in the Beagle and Norwegian Elkhound. The closely related gene, ADAMTS17, has also been associated with several different ocular phenotypes in multiple breeds of dog, including primary lens luxation and POAG. We investigated ADAMTS17 as a candidate gene for POAG in the Basset Hound and Basset Fauve de Bretagne dog breeds. Methods We performed ADAMTS17 exon resequencing in three Basset Hounds and three Basset Fauve de Bretagne dogs with POAG. Identified variants were genotyped in additional sample cohorts of both breeds and dogs of other breeds to confirm their association with disease. Results All affected Basset Hounds were homozygous for a 19 bp deletion in exon 2 that alters the reading frame and is predicted to lead to a truncated protein. Fifty clinically unaffected Basset Hounds were genotyped for this mutation and all were either heterozygous or homozygous for the wild type allele. Genotyping of 223 Basset Hounds recruited for a different study revealed a mutation frequency of 0.081 and predicted frequency of affected dogs in the population to be 0.007. Based on the entire genotyping dataset the association statistic for the POAG-associated deletion was p = 1.26 x 10−10. All affected Basset Fauve de Bretagne dogs were homozygous for a missense mutation in exon 11 causing a glycine to serine amino acid substitution (G519S) in the disintegrin-like domain of ADAMTS17 which is predicted to alter protein function. Unaffected Basset Fauve de Bretagne dogs were either heterozygous for the mutation (5/24) or homozygous for the wild type allele (19/24). Based on the entire genotyping dataset the association statistic for the POAG-associated deletion was p = 2.80 x 10−7. Genotyping of 85 dogs of unrelated breeds and 90 dogs of related breeds for this variant was negative. Conclusion This report documents strong associations between two independent ADAMTS17 mutations and POAG in two different dog breeds.
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Affiliation(s)
- James A. C. Oliver
- Department of Canine Genetics Research, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk, United Kingdom
- * E-mail:
| | - Oliver P. Forman
- Department of Canine Genetics Research, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk, United Kingdom
| | - Louise Pettitt
- Department of Canine Genetics Research, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk, United Kingdom
| | - Cathryn S. Mellersh
- Department of Canine Genetics Research, Centre for Preventive Medicine, Animal Health Trust, Newmarket, Suffolk, United Kingdom
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20
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Komáromy AM, Petersen-Jones SM. Genetics of Canine Primary Glaucomas. Vet Clin North Am Small Anim Pract 2015; 45:1159-82, v. [PMID: 26277300 DOI: 10.1016/j.cvsm.2015.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Primary glaucomas are a leading cause of incurable vision loss in dogs. Based on their specific breed predilection, a genetic cause is suspected to be responsible, and affected dogs should be excluded from breeding. Despite the high prevalence of primary glaucomas in dogs, their genetics have been studied in only a small number of breeds. The identification of canine glaucoma disease genes, and the development of genetic tests, will help to avoid the breeding of affected dogs in the future and will allow for earlier diagnosis and potentially more effective therapy.
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Affiliation(s)
- András M Komáromy
- Department of Small Animal Clinical Sciences, Veterinary Medical Center, College of Veterinary Medicine, Michigan State University, 736 Wilson Road, Room D-208, East Lansing, MI 48824, USA.
| | - Simon M Petersen-Jones
- Department of Small Animal Clinical Sciences, Veterinary Medical Center, College of Veterinary Medicine, Michigan State University, 736 Wilson Road, Room D-208, East Lansing, MI 48824, USA
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21
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Hatami-Marbini H, Rahimi A. Collagen cross-linking treatment effects on corneal dynamic biomechanical properties. Exp Eye Res 2015; 135:88-92. [PMID: 25887295 DOI: 10.1016/j.exer.2015.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 02/10/2015] [Accepted: 04/13/2015] [Indexed: 10/23/2022]
Abstract
Cornea is a soft tissue with the principal function of transmitting and refracting light rays. The objective of the current study was to characterize possible effects of the riboflavin/UVA collagen cross-linking on corneal dynamic properties. The original corneal cross-linking protocol was used to induce cross-links in the anterior portion of the bovine cornea. A DMA machine was used to conduct mechanical tensile experiments at different levels of tensile strains. The samples were divided into a control group (n = 5) and a treated group (n = 5). All specimens were first stretched to a strain of 5% and allowed to relax for twenty minutes. After completion of the stress-relaxation experiment, a frequency sweep test with oscillations ranging from 0.01 to 10 Hz was performed. The same procedure was repeated to obtain the stress-relaxation and dynamic properties at 10% strain. It was observed that the collagen cross-linking therapy significantly increased the immediate and equilibrium tensile behavior of the bovine cornea (P < 0.05). Furthermore, for all samples in control and treated groups and throughout the whole range of frequencies, a significantly larger tensile storage modulus was measured at an axial strain of 10% compared to what was obtained at a tensile strain of 5%. Finally, it was noted that although this treatment procedure resulted in a significant increase in the storage and loss modulus at any axial strain and frequency (P < 0.05), it significantly reduced the ratio of the dissipated and stored energy during a single cycle of deformation. Therefore, it was concluded that while the riboflavin/UVA collagen cross-linking increased significantly corneal stiffness, it decreased significantly its damping capability and deformability. This reduced damping ability might adversely interfere with corneal mechanical performance.
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Affiliation(s)
- Hamed Hatami-Marbini
- Computational Biomechanics Laboratory, School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, OK, USA.
| | - Abdolrasol Rahimi
- Computational Biomechanics Laboratory, School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, OK, USA
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22
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Ahonen SJ, Kaukonen M, Nussdorfer FD, Harman CD, Komáromy AM, Lohi H. A novel missense mutation in ADAMTS10 in Norwegian Elkhound primary glaucoma. PLoS One 2014; 9:e111941. [PMID: 25372548 PMCID: PMC4221187 DOI: 10.1371/journal.pone.0111941] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/02/2014] [Indexed: 12/11/2022] Open
Abstract
Primary glaucoma is one of the most common causes of irreversible blindness both in humans and in dogs. Glaucoma is an optic neuropathy affecting the retinal ganglion cells and optic nerve, and elevated intraocular pressure is commonly associated with the disease. Glaucoma is broadly classified into primary open angle (POAG), primary closed angle (PCAG) and primary congenital glaucoma (PCG). Human glaucomas are genetically heterogeneous and multiple loci have been identified. Glaucoma affects several dog breeds but only three loci and one gene have been implicated so far. We have investigated the genetics of primary glaucoma in the Norwegian Elkhound (NE). We established a small pedigree around the affected NEs collected from Finland, US and UK and performed a genome-wide association study with 9 cases and 8 controls to map the glaucoma gene to 750 kb region on canine chromosome 20 (praw = 4.93×10−6, pgenome = 0.025). The associated region contains a previously identified glaucoma gene, ADAMTS10, which was subjected to mutation screening in the coding regions. A fully segregating missense mutation (p.A387T) in exon 9 was found in 14 cases and 572 unaffected NEs (pFisher = 3.5×10−27) with a high carrier frequency (25.3%). The mutation interrupts a highly conserved residue in the metalloprotease domain of ADAMTS10, likely affecting its functional capacity. Our study identifies the genetic cause of primary glaucoma in NEs and enables the development of a genetic test for breeding purposes. This study establishes also a new spontaneous canine model for glaucoma research to study the ADAMTS10 biology in optical neuropathy.
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Affiliation(s)
- Saija J. Ahonen
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Maria Kaukonen
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
| | - Forrest D. Nussdorfer
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - Christine D. Harman
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States of America
| | - András M. Komáromy
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, United States of America
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Hannes Lohi
- Department of Veterinary Biosciences and Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- The Folkhälsan Institute of Genetics, Helsinki, Finland
- * E-mail:
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