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Li W, Cao J, Liu J, Chen S, Dai M, Zhang M, Hou X, Wang J, Kang Z. Protective effect of Tetrandrine on optic nerve by inhibiting glial activation through NF-κB pathway. Heliyon 2024; 10:e24749. [PMID: 38370256 PMCID: PMC10867623 DOI: 10.1016/j.heliyon.2024.e24749] [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: 01/23/2023] [Revised: 12/09/2023] [Accepted: 01/12/2024] [Indexed: 02/20/2024] Open
Abstract
Introduction This study aimed to explore the effect and molecular mechanism of Tetrandrine (Tet) onlipopolysaccharide (LPS)-induceduveitis andoptic nerve injury in vivo and in vitro. Methods Uveitis was induced by LPS injected into the hindlimb foot pad of Wistar rats and was intervened by retroeyeball injection of Tet (100 nM, 1 μM or 10 μM).The anterior segment inflammation was observed by slit lamp. Tunelassay was used to detect the survival state of ganglion cells and nuclear layers of inner and outer. The detection of characteristic markers in different activation states of glial cells were performed by qualitative and quantitative test of immunofluorescence and western blotting. Also, western blotting was used to detect the expression of inflammatory factors in retina and the activation of nuclear factor kappa B (NF-κB) signal pathway. Meanwhile, routine blood test and function of liver and renal were performed. Results The ciliary hyperemia was obvious, and the iris vessels were dilated and tortuous in rats with LPS-induced uveitis. Tet-pretreated obviously elieved these symptoms. In addition, the dilation and hyperemia in Tet group were alleviated compared with LPS group, and the inflammatory scores in Tetgroup were significantly lower than those of LPS group. TUNEL Staining showed that the number ofretinal ganglion cell (RGCs) in Tetgroup was slightly less than that in normal group, but significantly more than that in LPS group, and the cells arranged orderly. Besides, the number of apoptotic cells was significantly less than that in LPS group. Tet reduced LPS-activated gliocyte in a dose-dependent manner. Tumour necrosis factor alpha (TNF-α), interleukin (IL)-1β, interferon gamma (γ-IFN) and IL-2 in retina were increased by LPS but decreased significantly viaTet-pretreatment. Moreover, LPS activate NF-κB signal pathway, while Tet efficiently inhibited this effect.Furthermore, injection of Tet did not damage theroutineblood, liver and kidney. Conclusions Retrobulbar injection of Tet significantly alleviatedLPS-induced uveitisand optic nerve injuryof rats by activating gliocyte and NF-κB signaling pathway.
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Affiliation(s)
- Weiyi Li
- Department of Ophthalmology, Shenzhen People's Hospital, The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology, Shenzhen, 518020, Guangdong, China
- School of Ophthalmology & Optometry Affiliated to Shenzhen University, Shenzhen, 518040, Guangdong, China
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Jing Cao
- Yinan Branch of Qilu Hospital of Shandong University, Linyi, 276300, Shandong, China
| | - Jian Liu
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Shuiling Chen
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Min Dai
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Mingming Zhang
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Xinyue Hou
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Jianquan Wang
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
| | - Zefeng Kang
- Eye Hospital, China Academy of Chinese Medical Sciences, Shijingshan, 100040, Beijing, China
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Goulart Nacácio E Silva S, Occhiutto ML, Costa VP. The use of Nicotinamide and Nicotinamide riboside as an adjunct therapy in the treatment of glaucoma. Eur J Ophthalmol 2023; 33:1801-1815. [PMID: 36916064 DOI: 10.1177/11206721231161101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
Abstract
Glaucoma is an optic neuropathy characterized by death of retinal ganglion cells (RGCs), which leads to progressive visual field loss and may result in blindness. Currently, the only available treatment to avoid or delay progression in glaucoma patients is to decrease intraocular pressure (IOP). However, despite adequate IOP control, approximately 25% of the patients continue to progress. To delay or prevent optic nerve damage in glaucoma, two forms of vitamin B3, nicotinamide (NAM) and nicotinamide riboside (NR) are emerging as viable adjuvant therapies. These compounds are nicotinamide adenine dinucleotide (NAD) precursors. NAD is essential for proper cell functioning and is involved in several metabolic activities, including protection against reactive oxygen species, contribution to the performance of various enzymes, and maintenance of mitochondrial function. Due to its beneficial effects and to the evidence of the reduction of NAD bioavailability with aging, researchers are seeking ways to replenish the cellular NAD pool, by administrating its precursors (NAM and NR), believing that it will reduce the RGC vulnerability to external stressors, such as increased IOP. This article attempts to analyze the current knowledge regarding the use of NAM and NR for the prevention and/or treatment of glaucoma.
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Cell-Based Neuroprotection of Retinal Ganglion Cells in Animal Models of Optic Neuropathies. BIOLOGY 2021; 10:biology10111181. [PMID: 34827174 PMCID: PMC8615038 DOI: 10.3390/biology10111181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022]
Abstract
Retinal ganglion cells (RGCs) comprise a heterogenous group of projection neurons that transmit visual information from the retina to the brain. Progressive degeneration of these cells, as it occurs in inflammatory, ischemic, traumatic or glaucomatous optic neuropathies, results in visual deterioration and is among the leading causes of irreversible blindness. Treatment options for these diseases are limited. Neuroprotective approaches aim to slow down and eventually halt the loss of ganglion cells in these disorders. In this review, we have summarized preclinical studies that have evaluated the efficacy of cell-based neuroprotective treatment strategies to rescue retinal ganglion cells from cell death. Intraocular transplantations of diverse genetically nonmodified cell types or cells engineered to overexpress neurotrophic factors have been demonstrated to result in significant attenuation of ganglion cell loss in animal models of different optic neuropathies. Cell-based combinatorial neuroprotective approaches represent a potential strategy to further increase the survival rates of retinal ganglion cells. However, data about the long-term impact of the different cell-based treatment strategies on retinal ganglion cell survival and detailed analyses of potential adverse effects of a sustained intraocular delivery of neurotrophic factors on retina structure and function are limited, making it difficult to assess their therapeutic potential.
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Shen J, Wang Y, Yao K. Protection of retinal ganglion cells in glaucoma: Current status and future. Exp Eye Res 2021; 205:108506. [PMID: 33609512 DOI: 10.1016/j.exer.2021.108506] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 01/29/2021] [Accepted: 02/12/2021] [Indexed: 02/08/2023]
Abstract
Glaucoma is a neuropathic disease that causes optic nerve damage, loss of retinal ganglion cells (RGCs), and visual field defects. Most glaucoma patients have no early signs or symptoms. Conventional pharmacological glaucoma medications and surgeries that focus on lowering intraocular pressure are not sufficient; RGCs continue to die, and the patient's vision continues to decline. Recent evidence has demonstrated that neuroprotective approaches could be a promising strategy for protecting against glaucoma. In the case of glaucoma, neuroprotection aims to prevent or slow down disease progression by mitigating RGCs death and optic nerve degeneration. Notably, new pharmacologic medications such as antiglaucomatous agents, antibiotics, dietary supplementation, novel neuroprotective molecules, neurotrophic factors, translational methods such as gene therapy and cell therapy, and electrical stimulation-based physiotherapy are emerging to attenuate the death of RGCs, or to make RGCs resilient to attacks. Understanding the roles of these interventions in RGC protection may offer benefits over traditional pharmacological medications and surgeries. In this review, we summarize the recent neuroprotective strategy for glaucoma, both in clinical trials and in laboratory research.
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Affiliation(s)
- Junhui Shen
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China; Key Laboratory of Ophthalmology of Zhejiang Province, Hangzhou, Zhejiang, 310009, China
| | - Yuanqi Wang
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China; Key Laboratory of Ophthalmology of Zhejiang Province, Hangzhou, Zhejiang, 310009, China
| | - Ke Yao
- Eye Center, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310009, China; Key Laboratory of Ophthalmology of Zhejiang Province, Hangzhou, Zhejiang, 310009, China.
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Cheng CSM, Lee YF, Ong C, Yap ZL, Tsai A, Mohla A, Nongpiur ME, Aung T, Perera SA. Inter-eye comparison of retinal oximetry and vessel caliber between eyes with asymmetrical glaucoma severity in different glaucoma subtypes. Clin Ophthalmol 2016; 10:1315-21. [PMID: 27486303 PMCID: PMC4958362 DOI: 10.2147/opth.s96529] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background To compare retinal vessel oxygenation and vessel caliber in primary angle-closure glaucoma (PACG), primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and normal controls, as well as between eyes of asymmetrical glaucoma severity. Methods This was a prospective, cross-sectional study. The 159 subjects (PACG, n=39; POAG, n=41; NTG, n=41; normal controls, n=38) underwent retinal oxygen saturation measurements using the Oxymap T1 Retinal Oximeter, optical coherence tomography, and Humphrey visual field testing. Retinal oxygen saturation and vessel diameter were compared between the glaucoma groups and normal controls, as well as between eyes of asymmetrical glaucoma severity. Kruskal–Wallis test was performed for comparison among different subtypes of glaucoma. Wilcoxon signed-rank test was used to compare the inter-eye differences. Results Compared to normal controls, arteriolar oxygen saturation was increased in PACG eyes (P=0.048) but not in POAG or NTG eyes. There were no significant differences in oxygen saturation in venules or arteriovenous (AV) difference in all three glaucoma groups. Venular diameter was significantly reduced in all glaucoma groups compared to normal controls (P<0.001), but no such change was observed in arteriolar diameter (P=0.10). When comparing between eyes of asymmetrical glaucoma severity, arteriolar oxygen saturation (P=0.03) and AV difference (P=0.04) were significantly higher, while arteriolar diameter was significantly lower (P=0.001) in the worse eye in PACG group. There were no significant differences in oximetric parameters or vessel calibers between the worse and the better eyes in POAG and NTG groups. Conclusion Eyes with PACG showed increased arteriolar oxygen saturation and increased AV difference. This was not observed in POAG and NTG eyes. Arteriolar diameter in PACG and venular diameter in all three glaucoma groups were reduced. The difference observed in PACG eyes may be due to an increased metabolic demand in the disease process compared to open-angle glaucoma.
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Affiliation(s)
- Clarissa Shu Ming Cheng
- Department of Ophthalmology, Tan Tock Seng Hospital; Department of Ophthalmology, Singapore National Eye Centre
| | - Yi Fang Lee
- Department of Ophthalmology, Singapore National Eye Centre
| | - Charles Ong
- Yong Loo Lin School of Medicine, National University of Singapore
| | - Zhu Li Yap
- Department of Ophthalmology, Singapore National Eye Centre
| | - Andrew Tsai
- Department of Ophthalmology, Singapore National Eye Centre
| | - Aditi Mohla
- Department of Ophthalmology, Singapore National Eye Centre
| | - Monisha E Nongpiur
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Tin Aung
- Department of Ophthalmology, Singapore National Eye Centre; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
| | - Shamira A Perera
- Department of Ophthalmology, Singapore National Eye Centre; Singapore Eye Research Institute, Singapore National Eye Centre, Singapore
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Sapienza A, Raveu AL, Reboussin E, Roubeix C, Boucher C, Dégardin J, Godefroy D, Rostène W, Reaux-Le Goazigo A, Baudouin C, Melik Parsadaniantz S. Bilateral neuroinflammatory processes in visual pathways induced by unilateral ocular hypertension in the rat. J Neuroinflammation 2016; 13:44. [PMID: 26897546 PMCID: PMC4761202 DOI: 10.1186/s12974-016-0509-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 02/11/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Glaucoma is one of the leading causes of irreversible blindness in the world. The major risk factor is elevated intraocular pressure (IOP) leading to progressive retinal ganglion cell (RGC) death from the optic nerve (ON) to visual pathways in the brain. Glaucoma has been reported to share mechanisms with neurodegenerative disorders. We therefore hypothesize that neuroinflammatory mechanisms in central visual pathways may contribute to the spread of glaucoma disease. The aim of the present study was to analyze the neuroinflammation processes that occur from the pathological retina to the superior colliculi (SCs) in a rat model of unilateral ocular hypertension induced by episcleral vein cauterization (EVC). RESULTS Six weeks after unilateral (right eye) EVC in male Long-Evans rats, we evaluated both the neurodegenerative process and the neuroinflammatory state in visual pathway tissues. RGCs immunolabeled (Brn3a(+)) in ipsilateral whole flat-mounted retina demonstrated peripheral RGC loss associated with tissue macrophage/microglia activation (CD68(+)). Gene expression analysis of hypertensive and normotensive retinas revealed a significant increase of pro-inflammatory genes such as CCL2, IL-1β, and Nox2 mRNA expression compared to naïve eyes. Importantly, we found an upregulation of pro-inflammatory markers such as IL-1β and TNFα and astrocyte and tissue macrophage/microglia activation in hypertensive and normotensive RGC projection sites in the SCs compared to a naïve SC. To understand how neuroinflammation in the hypertensive retina is sufficient to damage both right and left SCs and the normotensive retina, we used an inflammatory model consisting in an unilateral stereotaxic injection of TNFα (25 ng/μl) in the right SC of naïve rats. Two weeks after TNFα injection, using an optomotor test, we observed that rats had visual deficiency in both eyes. Furthermore, both SCs showed an upregulation of genes and proteins for astrocytes, microglia, and pro-inflammatory cytokines, notably IL-1β. In addition, both retinas exhibited a significant increase of inflammatory markers compared to a naïve retina. CONCLUSIONS All these data evidence the complex role played by the SCs in the propagation of neuroinflammatory events induced by unilateral ocular hypertension and provide a new insight into the spread of neurodegenerative diseases such as glaucoma.
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Affiliation(s)
- Anaïs Sapienza
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Anne-Laure Raveu
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Elodie Reboussin
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Christophe Roubeix
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Céline Boucher
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Julie Dégardin
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - David Godefroy
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - William Rostène
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Annabelle Reaux-Le Goazigo
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France
| | - Christophe Baudouin
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC, 28 rue de Charenton, 75012, Paris, France.,Department Ophthalmology, Hopital Ambroise Pare, AP HP, F-92100, Boulogne, France.,University Versailles St Quentin En Yvelines, F-78180, Montigny-Le-Bretonneux, France
| | - Stéphane Melik Parsadaniantz
- Sorbonne Universités, UPMC University of Paris 06, Institut de la Vision, 17 rue Moreau, 75012, Paris, France. .,INSERM U968, Institut de la Vision, 17 rue Moreau, 75012, Paris, France. .,CNRS UMR_7210, Institut de la Vision, 17 rue Moreau, 75012, Paris, France.
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Soluble Tumor Necrosis Factor Alpha Promotes Retinal Ganglion Cell Death in Glaucoma via Calcium-Permeable AMPA Receptor Activation. J Neurosci 2015; 35:12088-102. [PMID: 26338321 DOI: 10.1523/jneurosci.1273-15.2015] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED Loss of vision in glaucoma results from the selective death of retinal ganglion cells (RGCs). Tumor necrosis factor α (TNFα) signaling has been linked to RGC damage, however, the mechanism by which TNFα promotes neuronal death remains poorly defined. Using an in vivo rat glaucoma model, we show that TNFα is upregulated by Müller cells and microglia/macrophages soon after induction of ocular hypertension. Administration of XPro1595, a selective inhibitor of soluble TNFα, effectively protects RGC soma and axons. Using cobalt permeability assays, we further demonstrate that endogenous soluble TNFα triggers the upregulation of Ca(2+)-permeable AMPA receptor (CP-AMPAR) expression in RGCs of glaucomatous eyes. CP-AMPAR activation is not caused by defects in GluA2 subunit mRNA editing, but rather reflects selective downregulation of GluA2 in neurons exposed to elevated eye pressure. Intraocular administration of selective CP-AMPAR blockers promotes robust RGC survival supporting a critical role for non-NMDA glutamate receptors in neuronal death. Our study identifies glia-derived soluble TNFα as a major inducer of RGC death through activation of CP-AMPARs, thereby establishing a novel link between neuroinflammation and cell loss in glaucoma. SIGNIFICANCE STATEMENT Tumor necrosis factor α (TNFα) has been implicated in retinal ganglion cell (RGC) death, but how TNFα exerts this effect is poorly understood. We report that ocular hypertension, a major risk factor in glaucoma, upregulates TNFα production by Müller cells and microglia. Inhibition of soluble TNFα using a dominant-negative strategy effectively promotes RGC survival. We find that TNFα stimulates the expression of calcium-permeable AMPA receptors (CP-AMPAR) in RGCs, a response that does not depend on abnormal GluA2 mRNA editing but on selective downregulation of the GluA2 subunit by these neurons. Consistent with this, CP-AMPAR blockers promote robust RGC survival supporting a critical role for non-NMDA glutamate receptors in glaucomatous damage. This study identifies a novel mechanism by which glia-derived soluble TNFα modulates neuronal death in glaucoma.
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Fleischman D, Allingham RR. The role of cerebrospinal fluid pressure in glaucoma and other ophthalmic diseases: A review. Saudi J Ophthalmol 2013; 27:97-106. [PMID: 24227969 DOI: 10.1016/j.sjopt.2013.03.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Accepted: 03/11/2013] [Indexed: 01/27/2023] Open
Abstract
Glaucoma is one of the most common causes of blindness in the world. Well-known risk factors include age, race, a positive family history and elevated intraocular pressures. A newly proposed risk factor is decreased cerebrospinal fluid pressure (CSFP). This concept is based on the notion that a pressure differential exists across the lamina cribrosa, which separates the intraocular space from the subarachnoid fluid space. In this construct, an increased translaminar pressure difference will occur with a relative increase in elevated intraocular pressure or a reduction in CSFP. This net change in pressure is proposed to act on the tissues within the optic nerve head, potentially contributing to glaucomatous optic neuropathy. Similarly, patients with ocular hypertension who have elevated CSFPs, would enjoy a relatively protective effect from glaucomatous damage. This review will focus on the current literature pertaining to the role of CSFP in glaucoma. Additionally, the authors examine the relationship between glaucoma and other known CSFP-related ophthalmic disorders.
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Affiliation(s)
- David Fleischman
- Department of Ophthalmology, University of North Carolina Hospitals, Chapel Hill, NC, USA
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Xu YF, Fu LL, Jiang CH, Qin YW, Ni YQ, Fan JW. Naloxone inhibition of lipopolysaccharide-induced activation of retinal microglia is partly mediated via the p38 mitogen activated protein kinase signalling pathway. J Int Med Res 2013; 40:1438-48. [PMID: 22971495 DOI: 10.1177/147323001204000422] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVES To investigate the effects and underlying mechanism of action of naloxone on lipopolysaccharide (LPS)-induced activation of retinal microglia in vitro. METHODS Rat retinal microglia primary cultures were divided into four treatment groups: untreated; 1 μg/ml LPS for 12 h; 0.5, 1.0 or 2.0 μM naloxone for 30 min before LPS; 2.5 or 5.0 μM SB203580 for 12 h before LPS and naloxone. Levels of tumour necrosis factor (TNF)-α and interleukin (IL)-1β were determined by enzyme-linked immuno sorbent assay. Western blot analysis and double immunofluorescence were used to examine activation of the mitogen activated protein kinase (MAPK) signalling pathway. RESULTS LPS induced an increase in TNF-α and IL-1β in culture supernatants, which was dose-dependently inhibited by naloxone. Naloxone also dose-dependently inhibited LPS-induced increases in phosphorylated p38 MAPK. Pretreatment of cells with SB203580 attenuated the inhibitory effect of naloxone on TNF-α and IL-1β production. CONCLUSIONS Naloxone suppressed LPS-induced activation of cultured retinal microglia and this suppression appeared to occur partly through the p38 MAPK signalling pathway. Naloxone may have therapeutic potential in neuro degenerative diseases characterized by the activation of microglia.
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Affiliation(s)
- Y F Xu
- Department of Ophthalmology, Eye, Ear, Nose and Throat Hospital, Fudan University School of Medicine, Shanghai, China
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10
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Munemasa Y, Kitaoka Y. Molecular mechanisms of retinal ganglion cell degeneration in glaucoma and future prospects for cell body and axonal protection. Front Cell Neurosci 2013; 6:60. [PMID: 23316132 PMCID: PMC3540394 DOI: 10.3389/fncel.2012.00060] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 12/06/2012] [Indexed: 12/20/2022] Open
Abstract
Glaucoma, which affects more than 70 million people worldwide, is a heterogeneous group of disorders with a resultant common denominator; optic neuropathy, eventually leading to irreversible blindness. The clinical manifestations of primary open-angle glaucoma (POAG), the most common subtype of glaucoma, include excavation of the optic disc and progressive loss of visual field. Axonal degeneration of retinal ganglion cells (RGCs) and apoptotic death of their cell bodies are observed in glaucoma, in which the reduction of intraocular pressure (IOP) is known to slow progression of the disease. A pattern of localized retinal nerve fiber layer (RNFL) defects in glaucoma patients indicates that axonal degeneration may precede RGC body death in this condition. The mechanisms of degeneration of neuronal cell bodies and their axons may differ. In this review, we addressed the molecular mechanisms of cell body death and axonal degeneration in glaucoma and proposed axonal protection in addition to cell body protection. The concept of axonal protection may become a new therapeutic strategy to prevent further axonal degeneration or revive dying axons in patients with preperimetric glaucoma. Further study will be needed to clarify whether the combination therapy of axonal protection and cell body protection will have greater protective effects in early or progressive glaucomatous optic neuropathy (GON).
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Affiliation(s)
- Yasunari Munemasa
- Department of Ophthalmology, St. Marianna University School of Medicine Kawasaki, Kanagawa, Japan
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11
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Pascale A, Drago F, Govoni S. Protecting the retinal neurons from glaucoma: lowering ocular pressure is not enough. Pharmacol Res 2012; 66:19-32. [PMID: 22433276 DOI: 10.1016/j.phrs.2012.03.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 02/28/2012] [Accepted: 03/05/2012] [Indexed: 01/01/2023]
Abstract
The retina is theater of a number of biochemical reactions allowing, within its layers, the conversion of light impulses into electrical signals. The axons of the last neuronal elements, the ganglion cells, form the optic nerve and transfer the signals to the brain. Therefore, an appropriate cellular communication, not only within the different retinal cells, but also between the retina itself and the other brain structures, is fundamental. One of the most diffuse pathologies affecting retinal function and communication, which thus reverberates in the whole visual system, is glaucoma. This insidious disease is characterized by a progressive optic nerve degeneration and sight loss which may finally lead to irreversible blindness. Nevertheless, the progressive nature of this pathology offers an opportunity for therapeutic intervention. To better understand the cellular processes implicated in the development of glaucoma useful to envision a targeted pharmacological strategy, this manuscript first examines the complex cellular and functional organization of the retina and subsequently identifies the targets sensitive to neurodegeneration. Within this context, high ocular pressure represents a key risk factor. However, recent literature findings highlight the concept that lowering ocular pressure is not enough to prevent/slow down glaucomatous damage, suggesting the importance of combining the hypotensive treatment with other pharmacological approaches, such as the use of neuroprotectants. Therefore, this important and more novel aspect is extensively considered in this review, also emphasizing the idea that the neuroprotective strategy should be extended to the entire visual system and not restricted to the retina.
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Affiliation(s)
- Alessia Pascale
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
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12
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The molecular basis of retinal ganglion cell death in glaucoma. Prog Retin Eye Res 2012; 31:152-81. [DOI: 10.1016/j.preteyeres.2011.11.002] [Citation(s) in RCA: 565] [Impact Index Per Article: 47.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 10/28/2011] [Accepted: 11/01/2011] [Indexed: 12/14/2022]
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13
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Ni YQ, Gan DK, Xu HD, Xu GZ, Da CD. Neuroprotective effect of transcorneal electrical stimulation on light-induced photoreceptor degeneration. Exp Neurol 2009; 219:439-52. [PMID: 19576889 DOI: 10.1016/j.expneurol.2009.06.016] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Revised: 06/17/2009] [Accepted: 06/20/2009] [Indexed: 10/20/2022]
Abstract
Direct electrical stimulation of neural tissues is a strategic approach to treat injured axons by accelerating their outgrowth [Al-Majed, A.A., Neumann, C.M., Brushart, T.M., Gordon, T., 2000. Brief electrical stimulation promotes the speed and accuracy of motor axonal regeneration. J. Neurosci. 20, 2602-2608] and promoting their regeneration [Geremia, N.M., Gordon, T., Brushart, T.M., Al-Majed, A.A., Verge, V.M.K., 2007. Electrical stimulation promotes sensory neuron regeneration and growth-associated gene expression. Exp. Neurol. 205, 347-359]. Recently, transcorneal electrical stimulation (TCES), a novel less invasive method, has been shown to rescue axotomized and damaged retinal ganglion cells [Morimoto, T., Miyoshi, T., Matsuda, S., Tano, Y., Fujikado, T., Fukuda, Y., 2005. Transcorneal electrical stimulation rescues axotomized retinal ganglion cells by activating endogenous retinal IGF-1 system. Invest. Ophthalmol. Vis. Sci. 46(6), 2147-2155]. Here, we investigated the neuroprotection of TCES on light-induced photoreceptor degeneration and the underlying mechanism. Adult male Sprague-Dawley (SD) rats received TCES before (pre-TCES) or after (post-TCES) intense light exposure. After fourteen days of light exposure, retinal histology and electroretinography were performed to evaluate the neuroprotective effect of TCES. The mRNA and protein levels of apoptotic-associated genes including Bcl-2, Bax, Caspase-3 as well as ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) in the retinas were determined by real-time PCR and Western blot analysis. The localization of these gene products in the retinas was examined by immunohistochemistry. Both pre- and post-TCES ameliorated the progressive photoreceptor degeneration. The degree of rescue depended on the strength of the electric charge. Post-TCES showed a relatively better and longer-term protective effect than pre-TCES. Real-time PCR and Western blot analysis revealed an upregulation of Bcl-2, CNTF, and BDNF and a downregulation of Bax in the retinas after TCES. Immunohistochemical studies showed that Bcl-2 and CNTF were selectively upregulated in Müller cells. These findings provide a new therapeutic method to prevent or delay photoreceptor degeneration through activating the intrinsic survival system.
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Affiliation(s)
- Ying-qin Ni
- Department of Ophthalmology, Eye and ENT Hospital of Fudan University, 83 Fen Yang Road, Shanghai 200031, People's Republic of China
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14
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Dendritic and Synaptic Protection: Is It Enough to Save the Retinal Ganglion Cell Body and Axon? J Neuroophthalmol 2008; 28:144-54. [DOI: 10.1097/wno.0b013e318177edf0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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15
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Kim HS, Park CK. Retinal ganglion cell death is delayed by activation of retinal intrinsic cell survival program. Brain Res 2006; 1057:17-28. [PMID: 16139821 DOI: 10.1016/j.brainres.2005.07.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2005] [Revised: 07/01/2005] [Accepted: 07/08/2005] [Indexed: 10/25/2022]
Abstract
Neuronal cells undergo apoptosis when deprived of neurotrophic factors due to injury, trauma, or neurodegenerative disease. This study examined cell death in the retina after chronic elevation of intraocular pressure (IOP) in an experimental rat model of human glaucomatous disease. Three episcleral veins on the ocular surface of rats were cauterized. Activation of several cell death programs represented by Fas ligand, FADD (Fas Associated Death Domain/Mort1) and the caspase cascade (caspase-8 and -3) and survival programs represented by phosphorylated protein kinase B (PKB/Akt), Bcl-2 associated death domain (BAD), and cAMP responsive element binding protein (CREB) were examined using immunohistochemistry and Western blotting. Following injury, two major events occurred simultaneously in the retina: activation of programmed cell death pathways and activation of survival mechanisms to maintain the cellular homeostasis of the retina. At the later stage of injury, markers of an activated cell death program appeared to be concentrated in the retinal ganglion cells. In conclusion, we suggest that endogenous cell survival factors triggered at the early stage of injury play a critical role in control of the death or survival of retinal ganglion cells and that the manipulation of this decision phase is one of the therapeutic targets for glaucoma.
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Affiliation(s)
- Hwa Sun Kim
- Department of Ophthalmology, College of Medicine, The Catholic University of Korea, 505 Banpo-dong, Seocho-ku, Seoul 137-701, South Korea
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16
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Zhou Y, Pernet V, Hauswirth WW, Di Polo A. Activation of the Extracellular Signal-Regulated Kinase 1/2 Pathway by AAV Gene Transfer Protects Retinal Ganglion Cells in Glaucoma. Mol Ther 2005; 12:402-12. [PMID: 15975850 DOI: 10.1016/j.ymthe.2005.04.004] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 04/11/2005] [Accepted: 04/11/2005] [Indexed: 11/18/2022] Open
Abstract
Glaucoma is the second leading cause of blindness in the world. Loss of vision in glaucomatous optic neuropathy is caused by the selective degeneration of retinal ganglion cells (RGCs). Ocular hypertension is a major risk factor in glaucoma, but visual field defects continue to progress in some patients despite the use of drugs that lower intraocular pressure. At present, there are no effective neuroprotective strategies for the treatment of this disease. The extracellular signal-regulated kinase (Erk) 1/2 pathway is an evolutionarily conserved mechanism used by several peptide factors to promote cell survival. Here we tested if selective activation of Erk1/2 protected RGCs in a rat model of experimental glaucoma. We used recombinant adeno-associated virus to transduce RGCs with genes encoding constitutively active or wild-type MEK1 (approved gene symbol MAP2K1), the upstream activator of Erk1/2. MEK1 gene transfer into RGCs markedly increased neuronal survival: 1366 +/- 70 RGCs/mm(2) (mean +/- SEM) were alive in the dorsal retina at 5 weeks after ocular hypertension surgery, a time when only 680 +/- 86 RGCs/mm(2) of these neurons remained in control eyes. We conclude that the Erk1/2 pathway plays a key role in the protection of RGCs from ocular hypertensive damage. This study identifies a novel gene therapy strategy in which selective activation of the Erk1/2 signaling pathway effectively slows cell death in glaucoma.
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Affiliation(s)
- Yu Zhou
- Department of Pathology and Cell Biology, Université de Montréal, 2900 Boulevard Edouard-Montpetit, Montreal, Quebec, Canada H3T 1J4
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17
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Abstract
Glaucoma is a family of diseases commonly characterised by progressive optic neuropathy with associated visual field deficits for which elevated intraocular pressure (IOP) is one of the primary risk factors. For more than a century the main goal of glaucoma management has been to eliminate the risk associated with elevated IOP. In recent years, accumulating evidence of pressure-independent causes of glaucomatous optic neuropathy has led to the recognition that lowering IOP alone may often be insufficient for the long-term preservation of visual function. An innovative therapeutic approach is now emerging to prevent progression of glaucomatous optic neuropathy and preserve vision, irrespective of disease aetiology: direct protection of the optic nerve. In addition to reducing the risk associated with elevated IOP, this neuroprotective approach will augment the overall goal of preserving the optic nerve through direct promotion of retinal ganglion cell (RGC) survival and/or prevention of RGC death. Although no currently available compounds have been clinically demonstrated to provide neuroprotective benefit in glaucoma, recent preclinical studies have shown that alpha-adrenergic agonists, such as brimonidine, provide neuroprotective benefits, as well as excellent IOP lowering efficacy. In addition, new agents with promising neuroprotective utility that are emerging from other studies are now being investigated for efficacy in glaucoma. The review discusses recently introduced compounds and new drugs in development with regard to their potential value in conventional and/or neuroprotective strategies for vision sparing in glaucoma.
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Affiliation(s)
- R David
- Allergan, 2525 Dupont Drive, PO Box 19534, Irvine, CA 92623-9534, USA
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18
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Neufeld AH. Pharmacologic neuroprotection with an inhibitor of nitric oxide synthase for the treatment of glaucoma. Brain Res Bull 2004; 62:455-9. [PMID: 15036557 DOI: 10.1016/j.brainresbull.2003.07.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2003] [Accepted: 07/07/2003] [Indexed: 10/26/2022]
Abstract
Excessive nitric oxide, generated by inducible NOS-2 in astrocytes and microglia in the optic nerve head of patients with glaucoma, may contribute to the optic neuropathy associated with the disease. A rat model of glaucoma, in which there is chronic, moderately elevated IOP and slow loss of retinal ganglion cells, has been established to study pharmacological agents that have the potential to be neuroprotective. In this model, the pharmacological use of an inhibitor of NOS-2, aminoguanidine, significantly prevents the loss of retinal ganglion cells. A well-tolerated pharmacological inhibitor of NOS-2, perhaps orally or locally delivered, is a reasonable candidate for a neuroprotective agent for treating glaucoma.
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Affiliation(s)
- Arthur H Neufeld
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, 660 South Euclid Avenue, Box 8096, St. Louis, MO 63110, USA.
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Yarangümeli A, Comoglu S, Köz OG, Elhan AH, Kural G. Effects of betaxolol and flunarizine on visual fields and intraocular pressure in patients with migraine. Doc Ophthalmol 2003; 106:265-70. [PMID: 12737504 DOI: 10.1023/a:1022925432197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Fifty-one patients with migraine were divided into four groups to investigate the effects of topical betaxolol and systemic calcium channel blocker flunarizine on visual fields (VF) and intraocular pressure (IOP). The first group (Group 0) was followed with no medications, topical betaxolol (bid) was precribed to the second group (Group B), oral flunarizine (10 mg daily) was prescribed to the third group (Group F), and the last group (Group BF) was assigned for combined betaxolol and flunarizine treatment. After a mean follow-up time of 4.2 +/- 1.2 months (3-6 months), IOP measurements and VF tests were repeated. Group B and Group BF were found to be statistically different from the other groups in terms of IOP reduction and VF improvement according to mean deviation and corrected pattern standard deviation indices in the second examinations. On the other hand, Group F and Group BF differed from the other two groups considering the improvement in migrainous complaints. VF findings which are probably influenced by perfusion problems due to vasospastic mechanisms in migraineurs, improved following topical betaxolol treatment. However, systemic use of flunarizine--a calcium channel blocker--did not seem to be effective on visual fields although it had beneficial effects on migraine.
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Affiliation(s)
- Alper Yarangümeli
- Ankara Numune Training and Research Hospital, 1st Eye Clinic, Ankara, Turkey.
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20
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Abstract
Apoptosis represents a mode of cellular death genetically programmed to maintain homeostasis of tissues. In specific pathologic circumstances, the death program may be activated by various environmental factors such as exposure to toxic substances or bacteria or deprivation of nutrients. From this point of view, apoptosis is considered the final event in several pathologies. In ophthalmology, experimental evidence has confirmed that apoptosis is a type of cellular death involved in various pathologic processes including glaucoma, retinitis pigmentosa, ischemic retinopathy, corneal reparative processes, cataract, and retinoblastoma. The aim of this article is to review the most recent results published in this field and to describe some of the molecular mechanisms responsible for the activation of the apoptotic program in some important ocular disorders. The understanding of such mechanisms could outline new therapeutic strategies for the prevention of cellular death in ophthalmology.
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Affiliation(s)
- G Carella
- Department of Ophthalmology and Visual Sciences, University Hospital San Raffaele, National Study Group on Apoptosis in Ophthalmology, Milano, Italy.
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21
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Abstract
UNLABELLED Brinzolamide is a highly specific carbonic anhydrase (CA) inhibitor which lowers intraocular pressure (IOP) by reducing the rate of aqueous humour formation. Formulated as a 1% ophthalmic suspension (Azopt) and administered twice or three times daily, brinzolamide is indicated for the topical management of primary open-angle glaucoma (POAG) and ocular hypertension (OH) as either monotherapy or adjunctive therapy with topical beta-blockers. As monotherapy in patients with POAG or OH, brinzolamide 1% demonstrated IOP-lowering efficacy that was significantly greater than placebo, equivalent to three-times-daily dorzolamide 2% but significantly lower than twice-daily timolol 0.5%. Brinzolamide 1% was equally effective in twice- and three-times-daily regimens producing diurnal mean IOP reductions from baseline in the range of 13.2-21.8%. When used adjunctively twice daily with timolol 0.5%, brinzolamide 1% was as effective as dorzolamide 2% and superior to placebo in lowering IOP in patients with POAG or OH. In clinical trials, brinzolamide 1% was well tolerated causing only nonserious adverse effects that were generally local, transient and mild to moderate in severity. The incidence of the most common adverse events associated with the use of brinzolamide 1% was either similar to (blurred vision and abnormal taste) or significantly lower than (ocular discomfort) with dorzolamide 2%. Topical brinzolamide 1% does not appear to produce the acid-base or electrolyte disturbances and severe systemic adverse effects characteristic of oral CA inhibitors. It can be used in patients unresponsive to beta-blockers or in whom beta-blockers are contraindicated. Brinzolamide 1% administered twice daily is among the least costly alternatives and adjuncts to beta-blocker therapy for glaucoma and is generally associated with less direct medical cost than dorzolamide. CONCLUSION Brinzolamide 1% ophthalmic suspension administered twice or three times daily, as monotherapy or adjunctive therapy with topical beta-blockers, has good IOP-lowering efficacy in patients with POAG or OH that is equivalent to that of dorzolamide 2% (three times daily as monotherapy, twice daily as adjunctive therapy). Brinzolamide is generally well tolerated and does not produce the systemic adverse effects associated with oral CA inhibitors. It can be used in patients who are unresponsive to, intolerant of, or unable to receive, ophthalmic beta-blockers. Thus, brinzolamide, either as monotherapy or adjunctive therapy with topical beta-blockers, should be regarded as a good second-line option in the pharmacological management of POAG and OH, and may be preferred over dorzolamide because of significantly less ocular discomfort.
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Farkas RH, Grosskreutz CL. Apoptosis, neuroprotection, and retinal ganglion cell death: an overview. Int Ophthalmol Clin 2001; 41:111-30. [PMID: 11198138 DOI: 10.1097/00004397-200101000-00011] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- R H Farkas
- Harvard Medical School, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles Street, Boston, MA 02114, USA
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23
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Lannek EB, Miller PE. Development of glaucoma after phacoemulsification for removal of cataracts in dogs: 22 cases (1987-1997). J Am Vet Med Assoc 2001; 218:70-6. [PMID: 11149718 DOI: 10.2460/javma.2001.218.70] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine factors contributing to glaucoma after lens extraction via phacoemulsification in dogs. DESIGN Retrospective study. ANIMALS 22 dogs (29 eyes) with glaucoma and 21 dogs (30 eyes) without glaucoma after phacoemulsification. PROCEDURE Medical record review. RESULTS Eyes at increased risk for glaucoma included those of Boston Terriers, those with uveal or retinal abnormalities before surgery, and those with intraoperative intraocular hemorrhage. Significant differences between groups were not detected for incidence of preoperative lens-induced uveitis, presence of an intraocular lens, or frequency of an acute postoperative increase in intraocular pressure. Glaucoma developed (mean +/- SD) 12.8+/-14.1 months (median, 10 months; range, 0.25 to 55 months) after surgery. Eighteen of 29 (62%) eyes with potential for vision after onset of glaucoma retained vision for a mean of 16.5+/-12.8 months (median, 10.8 months; range, 1.5 to 37 months) after glaucoma was diagnosed. Most of these eyes still had vision at the conclusion of the study period. CONCLUSIONS AND CLINICAL RELEVANCE Risk factors identified by this study will aid in preoperative counseling of clients and refining selection criteria for candidates for phacoemulsification. Careful follow-up for the remainder of the dog's life after surgery may improve long-term success rates by permitting early intervention before intraocular pressure increases substantially and vision is irreversibly lost. Surgery for cataracts may still be worthwhile in dogs with increased risk of glaucoma, especially if elderly, because of the lengthy period to onset of glaucoma after surgery and the beneficial effects of treatment after glaucoma develops.
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Affiliation(s)
- E B Lannek
- Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin, Madison 53706-1102, USA
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Arend O, Remky A, Cantor LB, Harris A. Altitudinal visual field asymmetry is coupled with altered retinal circulation in patients with normal pressure glaucoma. Br J Ophthalmol 2000; 84:1008-12. [PMID: 10966955 PMCID: PMC1723619 DOI: 10.1136/bjo.84.9.1008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
AIM To compare the effect of altitudinal asymmetric glaucomatous damage on retinal microcirculation in patients with normal pressure glaucoma (NPG). METHODS In a prospective cross sectional study patients with NPG (washed out for antiglaucomatous therapy) and altitudinal asymmetric perimetric findings between the superior and inferior hemisphere (Humphrey 24-2) (n=18) were included and compared with 20 NPG patients with symmetrical field defects and 18 healthy subjects. Fluorescein angiograms were performed using a scanning laser ophthalmoscope. Using digital image analysis, arteriovenous passage time (AVP) and vessel diameters were assessed for comparison of corresponding affected and less affected temporal arcades. RESULTS Both affected and less affected hemispheres showed significantly prolonged AVP times (p<0.001) when compared with healthy subject data. In hemispheres with more severe glaucomatous field loss the AVP times were significantly (p=0.04) prolonged compared with the less affected hemisphere (AVP affected 3.1 (SD 7) seconds v AVP less affected 2.61 (1.4) seconds). There was no asymmetry effect on arterial and venous diameter measurements. CONCLUSION Altitudinal visual field defects are linked together with circulatory deficits of the retinal tissue. The attenuated circulation seems to be a considerable factor in the natural course of glaucomatous optic neuropathy.
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Affiliation(s)
- O Arend
- Department of Ophthalmology, Medical School of the Technical University of Aachen, Pauwelsstrasse 30, 52057 Aachen, Germany.
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25
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Abstract
In 2000 an estimated 66.8 million people worldwide will have glaucoma, 6.7 million of whom will be bilaterally blind from irreversible optic-nerve damage. Yet even in developed countries with public educational programmes that target glaucoma, half of the individuals with glaucoma remain undiagnosed. Patients with even mild visual impairment secondary to glaucoma may have difficulties with mobility, driving, and social interactions. Although glaucoma may be associated with increased eye pressures, its diagnosis does not rely on a specific level of eye pressure. Diagnosis of glaucoma often relies on examination of the optic disc and assessment of the visual field. The two most common types of glaucoma--primary open-angle glaucoma and primary angle-closure glaucoma--have different risk factors. Although similar medications can be used to treat these two types of glaucoma, the overall management of patients differs in important ways. Until recently, there were no randomised clinical trials that showed the effectiveness of lowering eye pressures with medications or surgery in patients with glaucoma. However, in 1998 a randomised clinical trial showed the benefit of lowering eye pressure in patients with glaucoma who had eye pressures of 24 mm Hg or less. Because glaucoma is treatable, and because the visual impairment from glaucoma is irreversible, early detection of the disease is critically important.
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Affiliation(s)
- A L Coleman
- Department of Ophthalmology, Jules Stein Eye Institute, University of California, Los Angeles 90095, USA.
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26
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Abstract
Visual field loss in glaucoma is due to death of retinal ganglion cells. Reducing or slowing down the loss of ganglion cells in glaucoma, a concept known as neuroprotection, would appear to be the only way forward. This does not imply that treatment of risk factors, such as elevated intraocular pressure, must not be continuously implemented. In this paper we point out that very little is known about the mechanisms of ganglion cell death in glaucoma and that data derived from studies on the "ideal animal model for glaucoma" must not be overemphasized. We also propose that the death processes of neurones in various diseases are fundamentally the same but vary in cause. Experimental data show that the death rate of neuronal populations is dependent on the impact of the insult and that neuroprotectants are more likely to benefit a patient in diseases in which the neurones die slowly, as in glaucoma, than in a disease in which the death of a set of neurones is rapid. We conclude that if a putative neuroprotectant can be administered in such a way that it reaches the retina in appropriate amounts and has insignificant side effects, it is likely to attenuate ganglion cell death and thus benefit the glaucoma patient.
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Affiliation(s)
- N N Osborne
- Nuffield Laboratory of Ophthalmology, Oxford University, UK
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27
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Howell N. Leber hereditary optic neuropathy: Potential opportunities/potential pitfalls for drug therapy of optic nerve degenerative disorders. Drug Dev Res 1999. [DOI: 10.1002/(sici)1098-2299(199901)46:1<34::aid-ddr6>3.0.co;2-a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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