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Sikiric P, Kokot A, Kralj T, Zlatar M, Masnec S, Lazic R, Loncaric K, Oroz K, Sablic M, Boljesic M, Antunovic M, Sikiric S, Strbe S, Stambolija V, Beketic Oreskovic L, Kavelj I, Novosel L, Zubcic S, Krezic I, Skrtic A, Jurjevic I, Boban Blagaic A, Seiwerth S, Staresinic M. Stable Gastric Pentadecapeptide BPC 157-Possible Novel Therapy of Glaucoma and Other Ocular Conditions. Pharmaceuticals (Basel) 2023; 16:1052. [PMID: 37513963 PMCID: PMC10385428 DOI: 10.3390/ph16071052] [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: 05/05/2023] [Revised: 07/01/2023] [Accepted: 07/20/2023] [Indexed: 07/30/2023] Open
Abstract
Recently, stable gastric pentadecapeptide BPC 157 therapy by activation of collateral pathways counteracted various occlusion/occlusion-like syndromes, vascular, and multiorgan failure, and blood pressure disturbances in rats with permanent major vessel occlusion and similar procedures disabling endothelium function. Thereby, we revealed BPC 157 cytoprotective therapy with strong vascular rescuing capabilities in glaucoma therapy. With these capabilities, BPC 157 therapy can recover glaucomatous rats, normalize intraocular pressure, maintain retinal integrity, recover pupil function, recover retinal ischemia, and corneal injuries (i.e., maintained transparency after complete corneal abrasion, corneal ulceration, and counteracted dry eye after lacrimal gland removal or corneal insensitivity). The most important point is that in glaucomatous rats (three of four episcleral veins cauterized) with high intraocular pressure, all BPC 157 regimens immediately normalized intraocular pressure. BPC 157-treated rats exhibited normal pupil diameter, microscopically well-preserved ganglion cells and optic nerve presentation, normal fundus presentation, nor- mal retinal and choroidal blood vessel presentation, and normal optic nerve presentation. The one episcleral vein rapidly upgraded to accomplish all functions in glaucomatous rats may correspond with occlusion/occlusion-like syndromes of the activated rescuing collateral pathway (azygos vein direct blood flow delivery). Normalized intraocular pressure in glaucomatous rats corresponded to the counteracted intra-cranial (superior sagittal sinus), portal, and caval hypertension, and aortal hypotension in occlusion/occlusion-like syndromes, were all attenuated/eliminated by BPC 157 therapy. Furthermore, given in other eye disturbances (i.e., retinal ischemia), BPC 157 instantly breaks a noxious chain of events, both at an early stage and an already advanced stage. Thus, we further advocate BPC 157 as a therapeutic agent in ocular disease.
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Affiliation(s)
- Predrag Sikiric
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Antonio Kokot
- Department of Anatomy and Neuroscience, Faculty of Medicine, J.J. Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Tamara Kralj
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Mirna Zlatar
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Sanja Masnec
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Ratimir Lazic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Kristina Loncaric
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Katarina Oroz
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Marko Sablic
- Department of Anatomy and Neuroscience, Faculty of Medicine, J.J. Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Marta Boljesic
- Department of Anatomy and Neuroscience, Faculty of Medicine, J.J. Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Marko Antunovic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Suncana Sikiric
- Department of Pathology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Sanja Strbe
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Vasilije Stambolija
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | | | - Ivana Kavelj
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Luka Novosel
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Slavica Zubcic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Ivan Krezic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Anita Skrtic
- Department of Pathology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Ivana Jurjevic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Alenka Boban Blagaic
- Department of Pharmacology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Sven Seiwerth
- Department of Pathology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Mario Staresinic
- Department of Surgery, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
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El-Nimri NW, Jiang L, Dahanayake D, Sweidan S, Smith BE, Wildsoet CF. Effect of topical latanoprost on choroidal thickness and vessel area in Guinea pigs. Exp Eye Res 2022; 225:109286. [PMID: 36283475 DOI: 10.1016/j.exer.2022.109286] [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: 07/24/2022] [Revised: 10/04/2022] [Accepted: 10/15/2022] [Indexed: 12/29/2022]
Abstract
The aim of this study was to investigate the effect of latanoprost, an ocular hypotensive agent and prostaglandin analog, on choroidal thickness and structure in young adult guinea pigs. Young (three-month-old) guinea pigs (n = 10) underwent daily monocular treatment with topical 0.005% latanoprost for 2 weeks, followed by a washout period of 2 weeks. Tonometry (iCare) and retinoscopy were undertaken to monitor intraocular pressure (IOP) and refractive error (recorded as spherical equivalent refractive error; SER), respectively. Axial length (AL) and choroidal thickness (ChT) were measured using high frequency A-scan ultrasonography, with additional ChT data, as well as choroidal vessel (ChV) areas obtained from posterior segment imaging using Spectral Domain-Optical Coherence Tomography (SD-OCT). Image J was used to analyze SD-OCT images. As expected, latanoprost significantly reduced IOP in treated eyes. Mean interocular IOP difference (±SE) changed from -0.40 ± 0.31 mmHg at baseline to -2.23 ± 0.43 mmHg after 2 weeks of treatment (p = 0.05). However, SER and AL were unaffected; interocular difference changed from 0.41 ± 0.58 to 0.38 ± 0.43 D and from -0.002 ± 0.02 mm to -0.007 ± 0.01 mm (p > 0.05), respectively. Latanoprost had minimal effect on ChT. Interocular ChT differences were 0.01 ± 0.06 μm at baseline and 0.04 ± 0.06 μm after 2 weeks of treatment (SD-OCT; p > 0.05). However, treated eyes had significant increased ChV areas; interocular differences changed from -0.76 ± 69.2 to 100.78 ± 66.9 μm2 after treatment (p = 0.04). While this study was limited to otherwise untreated young adult guinea pigs, the possibility that choroidal vessel enlargement contributes to the previously reported inhibitory effect of topical latanoprost on myopia progression in young guinea pigs warrants investigation.
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Affiliation(s)
- Nevin W El-Nimri
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States.
| | - Liqin Jiang
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States; Singapore Eye Research Institute, Singapore National Eye Centre, Duke-NUS Medical School, Singapore
| | - Dinasha Dahanayake
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States
| | - Sami Sweidan
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States
| | - Benjamin E Smith
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States
| | - Christine F Wildsoet
- School of Optometry and Vision Science, University of California Berkeley, Berkeley, CA, United States
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Stable Gastric Pentadecapeptide BPC 157 Therapy of Rat Glaucoma. Biomedicines 2021; 10:biomedicines10010089. [PMID: 35052769 PMCID: PMC8773185 DOI: 10.3390/biomedicines10010089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/27/2021] [Accepted: 12/28/2021] [Indexed: 12/17/2022] Open
Abstract
Cauterization of three episcleral veins (open-angle glaucoma model) induces venous congestion and increases intraocular pressure in rats. If not upgraded, one episcleral vein is regularly unable to acquire and take over the whole function, and glaucoma-like features persist. Recently, the rapid upgrading of the collateral pathways by a stable gastric pentadecapeptide BPC 157 has cured many severe syndromes induced by permanent occlusion of major vessels, veins and/or arteries, peripherally and centrally. In a six-week study, medication was given prophylactically (immediately before glaucoma surgery, i.e., three episcleral veins cauterization) or as curative treatment (starting at 24 h after glaucoma surgery). The daily regimen of BPC 157 (0.4 µg/eye, 0.4 ng/eye; 10 µg/kg, 10 ng/kg) was administered locally as drops in each eye, intraperitoneally (last application at 24 h before sacrifice) or per-orally in drinking water (0.16 µg/mL, 0.16 ng/mL, 12 mL/rat until the sacrifice, first application being intragastric). Consequently, all BPC 157 regimens immediately normalized intraocular pressure. BPC 157-treated rats exhibited normal pupil diameter, microscopically well-preserved ganglion cells and optic nerve presentation, normal fundus presentation, normal retinal and choroidal blood vessel presentation and normal optic nerve presentation. As leading symptoms, increased intraocular pressure and mydriasis, as well as degeneration of retinal ganglion cells, optic nerve head excavation and reduction in optic nerve thickness, generalized severe irregularity of retinal vessels, faint presentation of choroidal vessels and severe optic nerve disc atrophy were all counteracted. In conclusion, we claim that the reversal of the episcleral veins cauterization glaucoma appeared as a consequence of the BPC 157 therapy of the vessel occlusion-induced perilous syndrome.
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Nur İH, Saçmacı Ş, Orhan İ, Perez W, Testereci H. Morphological analysis of aqueous humor drainage using QD nanoparticles and indocyanine green. Microsc Res Tech 2020; 83:1032-1044. [PMID: 32445617 DOI: 10.1002/jemt.23494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 02/07/2020] [Accepted: 03/28/2020] [Indexed: 11/06/2022]
Abstract
This study represents the first morphological description of the lymphatic drainage of the ciliary body in vivo by comparative hyperspectral fluorescence imaging techniques of Quantum Qdot655 (QD) nanoparticles and indocyanine green (ICG). A volume of 1.25 μl of QD was injected into the left anterior camera of all rats. Similarly,1.25 μl of ICG diluted at a ratio of one-fourth with physiological saline solution was injected into the right anterior camera of all rats. The thickness of the skin in the mandibular area, connective tissue, and the depth of the mandibular lymph node (MLN) made image retrieval difficult. For QD, 302 nm UV excitation and 605 nm fluorescence peak emission were applied. The detection of QD and ICG used in this study in the MLNs is definitive evidence that aqueous humor (AH) follows a uveolymphatic pathway. Scanning electron microscope and the energy dispersive X-ray analyzer spectrum were used to examine both the Schlemm's canal and the MLN. For the first time, the QD was detected in the cortex of MLN. The QCM analysis of both QD-AH and ICG-AH was used to determine whether there was any interaction between them. This comparative study shows the importance of experimental animal modeling in pharmacological studies regarding eye research and drugs. In a female rat, the signal was taken from the parotid lymph node with QD injections.
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Affiliation(s)
- İsmail Hakkı Nur
- Department of Anatomy, Faculty of Veterinary Medicine, Erciyes University, Kayseri, Turkey
| | - Şerife Saçmacı
- Department of Chemistry, Science Faculty, Erciyes University, Kayseri, Turkey
| | - İmdat Orhan
- Department of Anatomy, Faculty of Veterinary Medicine, Erciyes University, Kayseri, Turkey
| | - William Perez
- Área de Anatomía, Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay
| | - Haluk Testereci
- Department of Medical Biochemistry, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey
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Dutca LM, Rudd D, Robles V, Galor A, Garvin MK, Anderson MG. Effects of sustained daily latanoprost application on anterior chamber anatomy and physiology in mice. Sci Rep 2018; 8:13088. [PMID: 30166564 PMCID: PMC6117323 DOI: 10.1038/s41598-018-31280-1] [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: 11/22/2017] [Accepted: 08/13/2018] [Indexed: 12/04/2022] Open
Abstract
Latanoprost is a common glaucoma medication. Here, we study longitudinal effects of sustained latanoprost treatment on intraocular pressure (IOP) in C57BL/6J mice, as well as two potential side-effects, changes in iris pigmentation and central corneal thickness (CCT). Male C57BL/6J mice were treated daily for 16 weeks with latanoprost. Control mice were treated on the same schedule with the preservative used with latanoprost, benzalkonium chloride (BAK), or handled, without ocular treatments. IOP and CCT were studied at pre-treatment, 2 "early" time points, and 2 "late" time points; slit-lamp analysis performed at a late time point; and expression of corneal and iridial candidate genes analyzed at the end of the experiment. Latanoprost lowered IOP short, but not long-term. Sustained application of BAK consistently resulted in significant corneal thinning, whereas sustained treatment with latanoprost resulted in smaller and less consistent changes. Neither treatment affected iris pigmentation, corneal matrix metalloprotease expression or iridial pigment-related genes expression. In summary, latanoprost initially lowered IOP in C57BL/6J mice, but became less effective with sustained treatment, likely due to physiological adaptation. These results identify a new resource for studying changes in responsiveness associated with long-term treatment with latanoprost and highlight detrimental effects of commonly used preservative BAK.
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Affiliation(s)
- Laura M Dutca
- Center for Prevention and Treatment of Visual Loss Iowa City Veterans Administration Medical Center, Iowa City, IA, USA
- Department of Ophthalmology and Visual Science, University of Iowa, Iowa City, IA, USA
| | - Danielle Rudd
- Center for Prevention and Treatment of Visual Loss Iowa City Veterans Administration Medical Center, Iowa City, IA, USA
| | - Victor Robles
- Electrical and Computer Engineering, University of Iowa, Iowa City, IA, USA
| | - Anat Galor
- Miami Veterans Administration Medical Center and Bascom Palmer Institute, University of Miami, Miami, FL, USA
| | - Mona K Garvin
- Center for Prevention and Treatment of Visual Loss Iowa City Veterans Administration Medical Center, Iowa City, IA, USA
- Electrical and Computer Engineering, University of Iowa, Iowa City, IA, USA
| | - Michael G Anderson
- Center for Prevention and Treatment of Visual Loss Iowa City Veterans Administration Medical Center, Iowa City, IA, USA.
- Department of Ophthalmology and Visual Science, University of Iowa, Iowa City, IA, USA.
- Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA, USA.
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Villena A, Díaz F, Vidal L, Moreno M, Garcĺa-Campos J, De Vargas IP. Study of the effects of ocular hypotensive drugs on number of neurons in the retinal ganglion layer in a rat experimental glaucoma. Eur J Ophthalmol 2018; 19:963-70. [DOI: 10.1177/112067210901900611] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Alicia Villena
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Florentina Díaz
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Lourdes Vidal
- Department of Histology and Histopathology, School of Medicine, University of Málaga
| | - Mercedes Moreno
- Department of Ophthalmology, School of Medicine, University of Málaga - Spain
| | - Jose Garcĺa-Campos
- Department of Ophthalmology, School of Medicine, University of Málaga - Spain
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Toris CB, Gelfman C, Whitlock A, Sponsel WE, Rowe-Rendleman CL. Making Basic Science Studies in Glaucoma More Clinically Relevant: The Need for a Consensus. J Ocul Pharmacol Ther 2017; 33:501-518. [PMID: 28777040 DOI: 10.1089/jop.2017.0001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Glaucoma is a chronic, progressive, and debilitating optic neuropathy that causes retinal damage and visual defects. The pathophysiologic mechanisms of glaucoma remain ill-defined, and there is an indisputable need for contributions from basic science researchers in defining pathways for translational research. However, glaucoma researchers today face significant challenges due to the lack of a map of integrated pathways from bench to bedside and the lack of consensus statements to guide in choosing the right research questions, techniques, and model systems. Here, we present the case for the development of such maps and consensus statements, which are critical for faster development of the most efficacious glaucoma therapy. We underscore that interrogating the preclinical path of both successful and unsuccessful clinical programs is essential to defining future research. One aspect of this is evaluation of available preclinical research tools. To begin this process, we highlight the utility of currently available animal models for glaucoma and emphasize that there is a particular need for models of glaucoma with normal intraocular pressure. In addition, we outline a series of discoveries from cell-based, animal, and translational research that begin to reveal a map of glaucoma from cell biology to physiology to disease pathology. Completion of these maps requires input and consensus from the global glaucoma research community. This article sets the stage by outlining various approaches to such a consensus. Together, these efforts will help accelerate basic science research, leading to discoveries with significant clinical impact for people with glaucoma.
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Affiliation(s)
- Carol B Toris
- 1 Department of Ophthalmology and Visual Sciences, Case Western Reserve University , Cleveland, Ohio
| | | | | | - William E Sponsel
- 3 WESMD Professional Association , San Antonio, Texas.,4 Department of Biomedical Engineering, University of Texas San Antonio , San Antonio, Texas.,5 Department of Vision Sciences, University of the Incarnate Word , San Antonio, Texas
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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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Razali N, Agarwal R, Agarwal P, Kapitonova MY, Kannan Kutty M, Smirnov A, Salmah Bakar N, Ismail NM. Anterior and posterior segment changes in rat eyes with chronic steroid administration and their responsiveness to antiglaucoma drugs. Eur J Pharmacol 2014; 749:73-80. [PMID: 25481859 DOI: 10.1016/j.ejphar.2014.11.029] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 11/18/2014] [Accepted: 11/24/2014] [Indexed: 11/17/2022]
Abstract
Steroid-induced ocular hypertension (SIOH) is associated with topical and systemic use of steroids. However, SIOH-associated anterior and posterior segment morphological changes in rats have not been described widely. Here we describe the pattern of intraocular pressure (IOP) changes, quantitative assessment of trabecular meshwork (TM) and retinal morphological changes and changes in retinal redox status in response to chronic dexamethasone treatment in rats. We also evaluated the responsiveness of steroid-pretreated rat eyes to 5 different classes of antiglaucoma drugs that act by different mechanisms. Up to 80% of dexamethasone treated animals achieved significant and sustained IOP elevation. TM thickness was significantly increased and number of TM cells was significantly reduced in SIOH rats compared to the vehicle-treated rats. Quantitative assessment of retinal morphology showed significantly reduced thickness of ganglion cell layer (GCL) and inner retina (IR) in SIOH rats compared to vehicle-treated rats. Estimation of retinal antioxidants including catalase, superoxide dismutase and glutathione showed significantly increased retinal oxidative stress in SIOH animals. Furthermore, steroid-treated eyes showed significant IOP lowering in response to treatment with 5 different drug classes. This indicated the ability of SIOH eyes to respond to drugs acting by different mechanisms. In conclusion, SIOH was associated with significant morphological changes in TM and retina and retinal redox status. Additionally, SIOH eyes also showed IOP lowering in response to drugs that act by different mechanisms of action. Hence, SIOH rats appear to be an inexpensive and noninvasive model for studying the experimental antiglaucoma drugs for IOP lowering and neuroprotective effects.
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Affiliation(s)
- Norhafiza Razali
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Brain and Neuroscience Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia.
| | - Renu Agarwal
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Brain and Neuroscience Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
| | - Puneet Agarwal
- Faculty of Medicine, International Medical University, IMU Clinical School, Department of Ophthalmology, Jalan Rasah, Seremban, Malaysia
| | - Marina Y Kapitonova
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Drug Discovery and Health Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
| | - Methil Kannan Kutty
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Drug Discovery and Health Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
| | - Alexey Smirnov
- Pathological Anatomy Department, Volgograd State Medical University, 1, Pavshikh Bortsov Square, Volgograd 400131, Russia
| | - Nor Salmah Bakar
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Drug Discovery and Health Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
| | - Nafeeza M Ismail
- Faculty of Medicine, Universiti Teknologi MARA (UiTM), Sungai Buloh Campus, Jalan Hospital, 47000 Sungai Buloh, Selangor, Malaysia; Faculty of Medicine, Brain and Neuroscience Communities of Research, Universiti Teknologi MARA (UiTM), Shah Alam, Selangor, Malaysia
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Tam ALC, Gupta N, Zhang Z, Yücel YH. Latanoprost Stimulates Ocular Lymphatic Drainage: An In Vivo Nanotracer Study. Transl Vis Sci Technol 2013; 2:3. [PMID: 24049723 DOI: 10.1167/tvst.2.5.3] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 05/31/2013] [Indexed: 10/26/2022] Open
Abstract
PURPOSE Ocular lymphatics have been recently shown to contribute to aqueous humor outflow. It is not yet known whether lymphatic outflow can be stimulated by pharmacological agents. Here we determine whether latanoprost, a prostaglandin F2 alpha analog commonly used to lower IOP to treat glaucoma, increases lymphatic drainage from the eye. METHODS Lymphatic drainage in mice was assessed in vivo, in 11 latanoprost-treated and 11 control animals using hyperspectral imaging at multiple times following quantum dot (QD) injection into the eye. QD signal intensity was also measured in tissue sections using hyperspectral imaging. RESULTS In the latanoprost-treated group, lymphatic drainage rate into the submandibular lymph node was increased compared with controls (1.23 ± 1.06 hours-1 vs. 0.30 ± 0.17 hours-1, mean ± SD, P < 0.02). Total QD signal intensity in the submandibular lymph node was greater in the latanoprost-treated group compared with controls (10.55 ± 1.12 vs. 9.48 ± 1.24, log scale, P < 0.05). CONCLUSIONS This is the first evidence that latanoprost increases lymphatic drainage from the eye. The pharmacological manipulation of this newly identified lymphatic outflow pathway may be relevant to treatments aimed at lowering intraocular pressure in glaucoma. TRANSLATIONAL RELEVANCE This is the first evidence that a prostaglandin drug widely prescribed for glaucoma, enhances lymphatic drainage from the eye. The pharmacological stimulation of this newly identified outflow pathway may be highly relevant to treatments aimed at lowering IOP to prevent blindness from glaucoma.
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Affiliation(s)
- Alex L C Tam
- Department of Ophthalmology and Vision Sciences, University of Toronto, Canada ; Keenan Research Centre at the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada
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Abdul Y, Akhter N, Husain S. Delta-opioid agonist SNC-121 protects retinal ganglion cell function in a chronic ocular hypertensive rat model. Invest Ophthalmol Vis Sci 2013; 54:1816-28. [PMID: 23404122 DOI: 10.1167/iovs.12-10741] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
PURPOSE This study examined if the delta-opioid (δ-opioid) receptor agonist, SNC-121, can improve retinal function and retinal ganglion cell (RGC) survival during glaucomatous injury in a chronic ocular hypertensive rat model. METHODS IOP was raised in brown Norway rats by injecting hypertonic saline into the limbal venous system. Rats were treated with 1 mg/kg SNC-121 (intraperitoneally [IP]) once daily for 7 days. Pattern-electroretinograms (PERGs) were obtained in response to contrast reversal of patterned visual stimuli. RGCs were visualized by fluorogold retrograde labeling. Expression of TNF-α and p38 mitogen-activated protein (MAP) kinase was measured by immunohistochemistry and Western blotting. RESULTS PERG amplitudes in ocular hypertensive eyes were significantly reduced (14.3 ± 0.60 μvolts) when compared with healthy eyes (18.0 ± 0.62 μvolts). PERG loss in hypertensive eyes was inhibited by SNC-121 treatment (17.20 ± 0.1.3 μvolts; P < 0.05). There was a 29% loss of RGCs in the ocular hypertensive eye, which was inhibited in the presence of SNC-121. TNF-α production and activation of p38 MAP kinase in retinal sections and optic nerve samples were upregulated in ocular hypertensive eyes and inhibited in the presence of SNC-121. Furthermore, TNF-α induced increase in p38 MAP kinase activation in astrocytes was inhibited in the presence of SNC-121. CONCLUSIONS These data provide evidence that activation of δ-opioid receptors inhibited the loss of PERG amplitudes and rate of RGC loss during glaucomatous injury. Mechanistic data provided clues that TNF-α is mainly produced from glial cells and activates p38 MAP kinase, which was significantly inhibited by SNC-121 treatment. Overall, data indicate that enhancement of δ-opioidergic activity in the eye may provide retina neuroprotection against glaucoma.
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Affiliation(s)
- Yasir Abdul
- Hewitt Laboratory of the Ola B. Williams Glaucoma Center, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, SC 29425, USA
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Husain S, Abdul Y, Crosson CE. Preservation of retina ganglion cell function by morphine in a chronic ocular-hypertensive rat model. Invest Ophthalmol Vis Sci 2012; 53:4289-98. [PMID: 22661469 DOI: 10.1167/iovs.12-9467] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
PURPOSE The current study examined if opioid-receptor-activation by morphine can improve retinal function and retinal ganglion cell (RGC) integrity in a chronic glaucoma rat model. METHODS IOP was raised in Brown Norway rats by injecting hypertonic saline into the limbal venous system. Rats were treated daily with 1 mg/kg morphine for 28 days at 24-hour intervals; animals were examined for changes in IOP by a TonoLab tonometer. Pattern-ERG (PERG) was obtained in response to contrast-reversal of patterned visual stimuli. RGCs were visualized by fluorogold retrograde-labeling. Changes in the expression pattern of TNF-α and caspases were measured by Western blotting. RESULTS A significant IOP elevation was seen as early as 7 days, and maintained for up to 8 weeks, after surgery. PERG amplitudes were significantly reduced in ocular-hypertensive eyes (15.84±0.74 μvolts) when compared with normal eyes (19±0.86 μvolts). PERG deficits in hypertensive eyes were reversed by morphine treatment (18.23±0.78 μvolts; P<0.05). In untreated rats, a 24% reduction in labeled RGCs was measured in the hypertensive eye compared with the normal eye. This reduction in RGC labeling was significantly ameliorated in the presence of morphine. In retinal samples, TNF-α, caspase-8, and caspase-3 expressions were significantly upregulated in ocular hypertensive eyes, but completely inhibited in the morphine-treated animals. CONCLUSIONS These data provide evidence that activation of opioid receptors can provide significant improvement in PERG and RGC integrity against glaucomatous injury. Mechanistic data provide clues that activation of one or more opioid receptors can reduce glaucomatous-injury via suppression of TNF-α and caspase activation.
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Affiliation(s)
- Shahid Husain
- Hewitt Laboratory of the Ola B. Williams Glaucoma Center, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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Yang Q, Cho KS, Chen H, Yu D, Wang WH, Luo G, Pang IH, Guo W, Chen DF. Microbead-induced ocular hypertensive mouse model for screening and testing of aqueous production suppressants for glaucoma. Invest Ophthalmol Vis Sci 2012; 53:3733-41. [PMID: 22599582 DOI: 10.1167/iovs.12-9814] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To characterize the microbead-induced ocular hypertension (OHT) mouse model and investigate its potential use for preclinical screening and evaluation of ocular hypotensive agents, we tested the model's responses to major antiglaucoma drugs. METHODS Adult C57BL/6J mice were induced to develop OHT unilaterally by intracameral injection of microbeads. The effects of the most commonly used ocular hypotensive drugs, including timolol, brimonidine, brinzolamide, pilocarpine, and latanoprost, on IOP and glaucomatous neural damage were evaluated. Degeneration of retinal ganglion cells (RGCs) and optic nerve axons were quantitatively assessed using immunofluorescence labeling and histochemistry. Thickness of the ganglion cell complex (GCC) was also assessed with spectral-domain optical coherence tomography (SD-OCT). RESULTS A microbead-induced OHT model promptly responded to drugs, such as timolol, brimonidine, and brinzolamide, that lower IOP through suppressing aqueous humor production and showed improved RGC and axon survival as compared to vehicle controls. Accordingly, SD-OCT detected significantly less reduction of GCC thickness in mice treated with all three aqueous production suppressants as compared to the vehicle contol-treated group. In contrast, drugs that increase aqueous outflow, such as pilocarpine and latanoprost, failed to decrease IOP in the microbead-induced OHT mice. CONCLUSIONS Microbead-induced OHT mice carry dysfunctional aqueous outflow facility and therefore offer a unique model that allows selective screening of aqueous production suppressant antiglaucoma drugs or for studying the mechanisms regulating aqueous humor production. Our data set the stage for using GCC thickness assessed by SD-OCT as an imaging biomarker for noninvasive tracking of neuronal benefits of glaucoma therapy in this model.
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Affiliation(s)
- Qiang Yang
- Department of Ophthalmology, Eye & ENT Hospital, Fudan University, Shanghai, P. R. China
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14
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Whitlock NA, Harrison B, Mixon T, Yu XQ, Wilson A, Gerhardt B, Eberhart DE, Abuin A, Rice DS. Decreased intraocular pressure in mice following either pharmacological or genetic inhibition of ROCK. J Ocul Pharmacol Ther 2009; 25:187-94. [PMID: 19456252 DOI: 10.1089/jop.2008.0142] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
PURPOSE Goals of this study were to determine if pharmacological or genetic inhibition of Rho-associated coiled coil containing protein kinases (known as ROCK1 and ROCK2) alters intraocular pressure (IOP) in mice. METHODS Micro-cannulation of the anterior chamber was used to measure IOP in wild-type B6.129 hybrid mice following treatment with ROCK inhibitors Y-27632 or Y-39983. For comparative purposes, wild-type mice were also treated with timolol, acetazolamide, pilocarpine, or latanoprost. Mice deficient in either Rock1 or Rock2 were generated by homologous recombination or gene trapping, respectively, and their IOP was determined using identical methods employed in the pharmacology studies. RESULTS Treatment of wild-type B6.129 hybrid mice with ROCK inhibitors (Y-27632 and Y-39983) resulted in significant reductions in IOP. The magnitude of IOP reduction observed with topical Y-39983 was comparable to timolol, and exceeded the IOP effects of latanoprost in this study. Pilocarpine had no discernible effect on IOP in mice. Moreover, mice deficient in either Rock1 or Rock2 exhibited a significant decrease in IOP compared to their B6.129 wild-type littermates. CONCLUSIONS Pharmacological or genetic inhibition of ROCKs results in decreased IOP in mice. The magnitude of IOP reduction is significant as demonstrated with comparative pharmacology using agents that lower IOP in humans. These studies support the ROCK pathway as a therapeutic target for treating ocular hypertension.
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Affiliation(s)
- N Andrew Whitlock
- Department of Ophthalmology, Lexicon Pharmaceuticals, The Woodlands, TX 77381, USA.
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15
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Husain S, Yates PW, Crosson CE. Latanoprost-induced changes in rat intraocular pressure: direct or indirect? J Ocul Pharmacol Ther 2009; 24:367-72. [PMID: 18665807 DOI: 10.1089/jop.2008.0042] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION The topical application of prostaglandin F(2 ) (FP)-receptor agonists has been shown to significantly lower intraocular pressure (IOP) in humans and is now considered the first-line treatment for ocular hypertension. Despite the prominent role FP-receptor agonists play in the treatment of glaucoma, our understanding of how these agents lower IOP remains incomplete. The present study was designed to evaluate the role of matrix metalloproteinase (MMP) activation and the cytokine, tumor necrosis factor alpha (TNF-alpha), in latanoprost-induced changes in IOP. METHODS Changes in IOP following an acute topical administration of latanoprost (60 ng) in normotensive Brown Norway rats were evaluated by means of a commercially available rebound tonometer. To examine the role of MMPs and TNF-alpha in this response, the rats were pretreated with a broad-spectrum MMP inhibitor, GM-6001 (100 microg), or the TNF-alpha inhibitor, thalidomide (25 microg). RESULTS The topical administration of latanoprost (60 ng) alone produced a biphasic change in ipsilateral IOP: an initial hypertension (4.21 +/- 0.52), followed by a prolonged hypotension (-4.79 +/- 0.65). In rats, pretreatment with GM-6001 blocked the latanoprost-induced reduction in IOP but did not prevent the initial rise in IOP. Pretreatment with thalidomide also blocked the ocular hypotension induced by latanoprost; however, thalidomide pretreatment enhanced the duration of the initial hypertension. CONCLUSIONS These results provide evidence that the secretion and activation of MMPs and the release of TNF-alpha play a central role in the ocular hypotension induced by FP-agonists. The administration of FP-agonists appears to lower IOP directly by inducing the activation of MMPs within the ciliary body, leading to improved uveoscleral outflow and indirectly through the release of TNF within the ciliary body. Secreted TNF-alpha may then activate TNF-receptors in the uvea and trabecular meshwork, increasing both uveoscleral and conventional outflow.
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Affiliation(s)
- Shahid Husain
- Hewitt Laboratory of the Ola B. Williams Glaucoma Center, Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA.
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Toris CB, Gabelt BT, Kaufman PL. Update on the mechanism of action of topical prostaglandins for intraocular pressure reduction. Surv Ophthalmol 2008; 53 Suppl1:S107-20. [PMID: 19038618 PMCID: PMC2727743 DOI: 10.1016/j.survophthal.2008.08.010] [Citation(s) in RCA: 214] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A decade has passed since the first topical prostaglandin analog was prescribed to reduce intraocular pressure (IOP) for the treatment of glaucoma. Now four prostaglandin analogs are available for clinical use around the world and more are in development. The three most efficacious of these drugs are latanoprost, travoprost, and bimatoprost, and their effects on IOP and aqueous humor dynamics are similar. A consistent finding is a substantial increase in uveoscleral outflow and a less consistent finding is an increase in trabecular outflow facility. Aqueous flow appears to be slightly stimulated as well. Prostaglandin receptors and their associated mRNAs have been located in the trabecular meshwork, ciliary muscle, and sclera, providing evidence that endogenous prostaglandins have a functional role in aqueous humor drainage. Earlier evidence found that topical PG analogs release endogenous prostaglandins. One well-studied mechanism for the enhancement of outflow by prostaglandins is the regulation of matrix metalloproteinases and remodeling of extracellular matrix. Other proposed mechanisms include widening of the connective tissue-filled spaces and changes in the shape of cells. All of these mechanisms alter the permeability of tissues of the outflow pathways leading to changes in outflow resistance and/or outflow rates. This review summarizes recent (since 2000) animal and clinical studies of the effects of topical prostaglandin analogs on aqueous humor dynamics and recent cellular and molecular studies designed to clarify the outflow effects.
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Affiliation(s)
- Carol B Toris
- Department of Ophthalmology, University of Nebraska Medical Center, Omaha, Nebraska 68198-5840, USA.
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Sharif NA, McLaughlin MA, Kelly CR, Katoli P, Drace C, Husain S, Crosson C, Toris C, Zhan GL, Camras C. Cabergoline: Pharmacology, ocular hypotensive studies in multiple species, and aqueous humor dynamic modulation in the Cynomolgus monkey eyes. Exp Eye Res 2008; 88:386-97. [PMID: 18992242 DOI: 10.1016/j.exer.2008.10.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Revised: 09/19/2008] [Accepted: 10/01/2008] [Indexed: 12/11/2022]
Abstract
The aims of the current studies were to determine the in vitro and in vivo ocular and non-ocular pharmacological properties of cabergoline using well documented receptor binding, cell-based functional assays, and in vivo models. Cabergoline bound to native and/or human cloned serotonin-2A/B/C (5HT(2A/B/C)), 5HT(1A), 5HT(7), alpha(2B), and dopamine-2/3 (D(2/3)) receptor subtypes with nanomolar affinity. Cabergoline was an agonist at human recombinant 5HT(2), 5HT(1A) and D(2/3) receptors but an antagonist at 5HT(7) and alpha(2) receptors. In primary human ciliary muscle (h-CM) and trabecular meshwork (h-TM) cells, cabergoline stimulated phosphoinositide (PI) hydrolysis (EC(50)=19+/-7 nM in TM; 76 nM in h-CM) and intracellular Ca(2+) ([Ca(2+)](i)) mobilization (EC(50)=570+/-83 nM in h-TM; EC(50)=900+/-320 nM in h-CM). Cabergoline-induced [Ca(2+)](i) mobilization in h-TM and h-CM cells was potently antagonized by a 5HT(2A)-selective antagonist (M-100907, K(i)=0.29-0.53 nM). Cabergoline also stimulated [Ca(2+)](i) mobilization more potently via human cloned 5HT(2A) (EC(50)=63.4+/-10.3 nM) than via 5HT(2B) and 5HT(2C) receptors. In h-CM cells, cabergoline (1 microM) stimulated production of pro-matrix metalloproteinases-1 and -3 and synergized with forskolin to enhance cAMP production. Cabergoline (1 microM) perfused through anterior segments of porcine eyes caused a significant (27%) increase in outflow facility. Topically administered cabergoline (300-500 microg) in Dutch-belted rabbit eyes yielded 4.5 microMM and 1.97 microM levels in the aqueous humor 30 min and 90 min post-dose but failed to modulate intraocular pressure (IOP). However, cabergoline was an efficacious IOP-lowering agent in normotensive Brown Norway rats (25% IOP decrease with 6 microg at 4h post-dose) and in conscious ocular hypertensive cynomolgus monkeys (peak reduction of 30.6+/-3.6% with 50 microg at 3h post-dose; 30.4+/-4.5% with 500 microg at 7h post-dose). In ketamine-sedated monkeys, IOP was significantly lowered at 2.5h after the second topical ocular dose (300 microg) of cabergoline by 23% (p<0.02) and 35% (p<0.004) in normotensive and ocular hypertensive eyes, respectively. In normotensive eyes, cabergoline increased uveoscleral outflow (0.69+/-0.7 microL/min-1.61+/-0.97 microL/min, n=13; p<0.01). However, only seven of the eleven ocular hypertensive monkeys showed significantly increased uveoscleral outflow. These data indicate that cabergoline's most prominent agonist activity involves activation of 5HT(2), 5HT(1A), and D(2/3) receptors. Since 5HT(1A) agonists, 5HT(7) antagonists, and alpha(2) antagonists do not lower IOP in conscious ocular hypertensive monkeys, the 5HT(2) and dopaminergic agonist activities of cabergoline probably mediated the IOP reduction observed with this compound in this species.
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Affiliation(s)
- Najam A Sharif
- Discovery Ophthalmology Research, Alcon Research Ltd, Fort worth, TX, USA.
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Zhang Y, Davidson BR, Stamer WD, Barton JK, Marmorstein LY, Marmorstein AD. Enhanced inflow and outflow rates despite lower IOP in bestrophin-2-deficient mice. Invest Ophthalmol Vis Sci 2008; 50:765-70. [PMID: 18936135 DOI: 10.1167/iovs.08-2501] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Bestrophin-2 (Best2), a putative Cl(-) channel is expressed in the nonpigmented epithelium (NPE). Disruption of Best2 in mice results in a diminished intraocular pressure (IOP). Aqueous humor dynamics were compared in Best2(+/+) and Best2(-/-) mice, to better understand the contribution of Best2 to IOP. METHODS Measurements of IOP, episcleral venous pressure (EVP), conventional outflow facility (C(t)), aqueous humor production (F(a)), and anterior chamber volume (V(a)) were made using anterior chamber cannulation. Conventional (F(c)) and uveoscleral outflow (F(u)), and rate of aqueous humor turnover, were calculated from measured data. The anterior chamber was examined in live mice by optical coherence tomography (OCT) and postmortem by light microscopy. RESULTS IOP in Best2(-/-) mice was lower compared with Best2(+/+) littermates. EVP was unchanged. Since Best2 is expressed in NPE cells, the hypothesis was that Best2 is involved in generating aqueous flow. However, F(a) in Best2(-/-) mice was increased by approximately 73% compared with Best2(+/+) mice. This was accompanied by increases in F(c) and F(u). Aqueous humor turnover was enhanced more than twofold in Best2(-/-) mice. No evidence of developmental structural changes was noted. CONCLUSIONS Best2 appears to antagonize the formation of aqueous humor and cause an inhibition of both F(c) and F(u), despite being expressed only in NPE cells. These data support the hypothesis that the inflow and outflow pathways communicate via soluble agents present in the aqueous humor and implicate Best2 as a critical mediator of that communication.
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Affiliation(s)
- Youwen Zhang
- Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona 85711, USA
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Bakall B, McLaughlin P, Stanton JB, Zhang Y, Hartzell HC, Marmorstein LY, Marmorstein AD. Bestrophin-2 is involved in the generation of intraocular pressure. Invest Ophthalmol Vis Sci 2008; 49:1563-70. [PMID: 18385076 DOI: 10.1167/iovs.07-1338] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The bestrophin family of proteins has been demonstrated to generate or regulate Ca2+-activated Cl(-) conductances. Mutations in bestrophin-1 (Best1) cause several blinding eye diseases, but little is known about other bestrophin family members. This study involved disruption of the Best2 gene in mice. METHODS The mouse Best2 gene was disrupted by replacing exons 1, 2, and part of exon 3 with a Lac Z. The expression profile of Bestrophin-2 (Best2) was examined using RT-PCR, X-gal staining, and immunohistochemistry. Intraocular pressure (IOP) was measured by anterior chamber cannulation. RESULTS RT-PCR of mouse tissues revealed Best2 mRNA in eye, colon, nasal epithelia, trachea, brain, lung, and kidney. X-gal staining, confirmed expression in colon epithelia and in the eye, in the nonpigmented epithelia (NPE). Best2 was not expressed in RPE cells. Best2 protein was observed only in NPE and colon epithelia. The absence of Best2 had no obvious deleterious effect on the mice. However, the Best2-/- mice were found to have significantly (P < 0.02) diminished IOP with respect to the Best2+/+ and Best2+/- littermates. The Best2-/- and Best2+/- mice responded better to the carbonic anhydrase inhibitor brinzolamide than did their Best2+/+ littermates, although the beta-blocker timolol brought IOP to the same level, regardless of genotype. CONCLUSIONS Best2 plays a role in the generation of IOP by regulating formation of aqueous humor, and inhibition of Best2 function represents an attractive new avenue for regulating IOP in individuals with glaucoma.
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Affiliation(s)
- Benjamin Bakall
- Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona
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Wang Z, Do CW, Avila MY, Stone RA, Jacobson KA, Civan MM. Barrier qualities of the mouse eye to topically applied drugs. Exp Eye Res 2007; 85:105-12. [PMID: 17490649 PMCID: PMC2151915 DOI: 10.1016/j.exer.2007.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2006] [Revised: 03/02/2007] [Accepted: 03/09/2007] [Indexed: 11/20/2022]
Abstract
The mouse eye displays unusually rapid intraocular pressure (IOP) responses to topically applied drugs as measured by the invasive servo-null micropipette system (SNMS). To learn if the time course reflected rapid drug transfer across the thin mouse cornea and sclera, we monitored a different parameter, pupillary size, following topical application of droplets containing 40 microM (0.073 microg) carbachol. No miosis developed from this low carbachol concentration unless the cornea was impaled with an exploring micropipette as used in the SNMS. We also compared the mouse IOP response to several purinergic drugs, measured by the invasive SNMS and non-invasive pneumotonometry. Responses to the previously studied non-selective adenosine-receptor (AR) agonist adenosine, the A(3)-selective agonist Cl-IB-MECA and the A(3)-selective antagonist MRS 1191 were all enhanced to varying degrees, in time and magnitude, by corneal impalement. We conclude that the thin ocular coats of the mouse eye actually present a substantial barrier to drug penetration. Corneal impalement with even fine-tipped micropipettes can significantly enhance entry of topically-applied drugs into the mouse aqueous humor, reflecting either direct diffusion around the tip or a more complex impalement-triggered change in ocular barrier properties. Comparison of invasive and non-invasive measurement methods can document drug efficacy at intraocular target sites even if topical drug penetration is too slow to manifest convincing physiologic effects in intact eyes.
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Affiliation(s)
- Zhao Wang
- Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
| | - Chi Wai Do
- Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
- School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Marcel Y. Avila
- Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
- Department of Physiological Sciences, Facultad de Medicina, Universidad Nacional de Colombia, Bogota, Colombia
| | - Richard A. Stone
- Department of Ophthalmology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
| | | | - Mortimer M. Civan
- Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
- Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6085
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