1
|
Pang IH, Clark AF. Inducible rodent models of glaucoma. Prog Retin Eye Res 2020; 75:100799. [PMID: 31557521 PMCID: PMC7085984 DOI: 10.1016/j.preteyeres.2019.100799] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 09/16/2019] [Accepted: 09/18/2019] [Indexed: 11/23/2022]
Abstract
Glaucoma is one of the leading causes of vision impairment worldwide. In order to further understand the molecular pathobiology of this disease and to develop better therapies, clinically relevant animal models are necessary. In recent years, both the rat and mouse have become popular models in glaucoma research. Key reasons are: many important biological similarities shared among rodent eyes and the human eye; development of improved methods to induce glaucoma and to evaluate glaucomatous damage; availability of genetic tools in the mouse; as well as the relatively low cost of rodent studies. Commonly studied rat and mouse glaucoma models include intraocular pressure (IOP)-dependent and pressure-independent models. The pressure-dependent models address the most important risk factor of elevated IOP, whereas the pressure-independent models assess "normal tension" glaucoma and other "non-IOP" related factors associated with glaucomatous damage. The current article provides descriptions of these models, their characterizations, specific techniques to induce glaucoma, mechanisms of injury, advantages, and limitations.
Collapse
Affiliation(s)
- Iok-Hou Pang
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, USA; Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Abbot F Clark
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, USA; Department of Pharmacology & Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, USA.
| |
Collapse
|
2
|
Bahr HI, Abdelghany AA, Galhom RA, Barakat BM, Arafa ESA, Fawzy MS. Duloxetine protects against experimental diabetic retinopathy in mice through retinal GFAP downregulation and modulation of neurotrophic factors. Exp Eye Res 2019; 186:107742. [PMID: 31344388 DOI: 10.1016/j.exer.2019.107742] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 07/19/2019] [Accepted: 07/19/2019] [Indexed: 12/23/2022]
Abstract
Diabetic retinopathy (DR) is recognized as one of the leading causes of blindness worldwide. Searching and validation for a novel therapeutic strategy to prevent its progress are promising. This work aimed to assess the retinal protective effects of duloxetine (DLX) in Alloxan-induced diabetic mice model. Animals were equally and randomly divided to four groups (eight mice per group); group 1: is the control group, 2: diabetic group, 3&4: diabetic and after 9 weeks received DLX for 4 weeks (15 mg/kg and 30 mg/kg), respectively. Quantitative real-time PCR (qPCR) analysis revealed nerve growth factor (NGF), inducible nitric oxide synthase (iNOS) and transforming growth factor beta (TGF-β) genes upregulation in the diabetic group compared to controls. Also, increased retinal malondialdehyde (MDA) and the decline of reduced glutathione (GSH) levels were observed. The morphometric analysis of diabetic retina revealed a significant reduction in total retinal thickness compared to control. Diabetic retinal immunostaining and Western blot analyses displayed glial fibrillary acidic protein (GFAP) and vascular endothelial cell growth factor (VEGF) proteins expression upregulation as well as glucose transporter-1 (GLUT-1) downregulation comparing to controls. However, DLX-treated groups showed downregulated NGF, iNOS, and TGF-β that was more obviously seen in the DLX-30 mg/kg group than DLX-15 mg/kg group. Furthermore, these groups showed amelioration of the oxidative markers; MDA and GSH, retaining the total retinal thickness nearly to control, GFAP and VEGF downregulation, and GLUT-1 upregulation compared to diabetic group. Taken together, it could be summarized that duloxetine can attenuate DR via the anti-inflammatory and the anti-oxidative properties as well as modulating the angiogenic and the neurotrophic factors expressions. This could hopefully pave the road to be included in the novel list of the therapeutic regimen for DR after validation in the clinic.
Collapse
Affiliation(s)
- Hoda I Bahr
- Department of Biochemistry, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| | - Ahmed A Abdelghany
- Department of Ophthalmology, Faculty of Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| | - Rania A Galhom
- Department of Human Anatomy and Embryology, Faculty of Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| | - Bassant M Barakat
- Department of Pharmacology and Toxicology, Faculty of Pharmacy (Girls), Al-Azhar University, Cairo, Egypt; Department of Clinical Pharmacy, College of Clinical Pharmacy, Al-Baha University, Al-Baha, Saudi Arabia.
| | - El-Shaimaa A Arafa
- Department of Clinical Sciences, College of Pharmacy and Health Sciences, Ajman University, Ajman, 346, United Arab Emirates; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt.
| | - Manal S Fawzy
- Department of Biochemistry, Faculty of Medicine, Northern Border University, Arar, Saudi Arabia; Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Suez Canal University, Ismailia, 41522, Egypt.
| |
Collapse
|
3
|
Abstract
The expression of serotonin (5-HT) in the retina was first reported in the sixties. The detection of vesicular monoamine transporter and serotonin receptors in several retinal cells confirm that 5-HT is playing a neuromodulatory role in this structure. Whereas signaling pathways activated by 5-HT receptor binding has been poorly investigated so far, numerous data demonstrated that 5-HT is involved in retinal physiology, retinal physiopathology and photoreceptor survival.
Collapse
|
4
|
Rizzo MI, Greco A, De Virgilio A, Gallo A, Taverniti L, Fusconi M, Conte M, Pagliuca G, Turchetta R, de Vincentiis M. Glaucoma: recent advances in the involvement of autoimmunity. Immunol Res 2018; 65:207-217. [PMID: 27475096 DOI: 10.1007/s12026-016-8837-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Glaucomatous optic neuropathy is the most commonly acquired optic neuropathy encountered in clinical practice. It is the second leading cause of blindness globally, after cataracts, but it presents a greater public health challenge than cataracts, because the blindness it causes is irreversible. It has pathogenesis still largely unknown and no established cure. Alterations in serum antibody profiles, upregulation, and downregulation have been described, but it still remains elusive if the autoantibodies seen in glaucoma are an epiphenomenon or causative. Hypertension, diabetes, and hearing disorders also are associated. This review is a glaucoma update with focus about the recent advances in the last 15 years.
Collapse
Affiliation(s)
- Maria Ida Rizzo
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy.,Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Antonio Greco
- Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Armando De Virgilio
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy. .,Department of Surgical Science, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy.
| | - Andrea Gallo
- Otorhinolaryngology Section, Department of Medico-Surgical Sciences and Biotechnologies, ''Sapienza'' University of Rome, Corso della Repubblica, 79, 04100, Latina, LT, Italy
| | - Luciano Taverniti
- Ophthalmology Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Massimo Fusconi
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Michela Conte
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Giulio Pagliuca
- Otorhinolaryngology Section, Department of Medico-Surgical Sciences and Biotechnologies, ''Sapienza'' University of Rome, Corso della Repubblica, 79, 04100, Latina, LT, Italy
| | - Rosaria Turchetta
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| | - Marco de Vincentiis
- ENT Section, Department Organs of Sense, University of Rome "La Sapienza", Viale del Policlinico 155, 00100, Rome, Italy
| |
Collapse
|
5
|
Retinal Neuroprotective Effects of Flibanserin, an FDA-Approved Dual Serotonin Receptor Agonist-Antagonist. PLoS One 2016; 11:e0159776. [PMID: 27447833 PMCID: PMC4957778 DOI: 10.1371/journal.pone.0159776] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 06/07/2016] [Indexed: 12/30/2022] Open
Abstract
PURPOSE To assess the neuroprotective effects of flibanserin (formerly BIMT-17), a dual 5-HT1A agonist and 5-HT2A antagonist, in a light-induced retinopathy model. METHODS Albino BALB/c mice were injected intraperitoneally with either vehicle or increasing doses of flibanserin ranging from 0.75 to 15 mg/kg flibanserin. To assess 5-HT1A-mediated effects, BALB/c mice were injected with 10 mg/kg WAY 100635, a 5-HT1A antagonist, prior to 6 mg/kg flibanserin and 5-HT1A knockout mice were injected with 6 mg/kg flibanserin. Injections were administered once immediately prior to light exposure or over the course of five days. Light exposure lasted for one hour at an intensity of 10,000 lux. Retinal structure was assessed using spectral domain optical coherence tomography and retinal function was assessed using electroretinography. To investigate the mechanisms of flibanserin-mediated neuroprotection, gene expression, measured by RT-qPCR, was assessed following five days of daily 15 mg/kg flibanserin injections. RESULTS A five-day treatment regimen of 3 to 15 mg/kg of flibanserin significantly preserved outer retinal structure and function in a dose-dependent manner. Additionally, a single-day treatment regimen of 6 to 15 mg/kg of flibanserin still provided significant protection. The action of flibanserin was hindered by the 5-HT1A antagonist, WAY 100635, and was not effective in 5-HT1A knockout mice. Creb, c-Jun, c-Fos, Bcl-2, Cast1, Nqo1, Sod1, and Cat were significantly increased in flibanserin-injected mice versus vehicle-injected mice. CONCLUSIONS Intraperitoneal delivery of flibanserin in a light-induced retinopathy mouse model provides retinal neuroprotection. Mechanistic data suggests that this effect is mediated through 5-HT1A receptors and that flibanserin augments the expression of genes capable of reducing mitochondrial dysfunction and oxidative stress. Since flibanserin is already FDA-approved for other indications, the potential to repurpose this drug for treating retinal degenerations merits further investigation.
Collapse
|
6
|
Tullis BE, Ryals RC, Coyner AS, Gale MJ, Nicholson A, Ku C, Regis D, Sinha W, Datta S, Wen Y, Yang P, Pennesi ME. Sarpogrelate, a 5-HT2A Receptor Antagonist, Protects the Retina From Light-Induced Retinopathy. Invest Ophthalmol Vis Sci 2015. [PMID: 26200496 DOI: 10.1167/iovs.15-16378] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
PURPOSE To determine if sarpogrelate, a selective 5-HT2A receptor antagonist, is protective against light-induced retinopathy in BALB/c mice. METHODS BALB/c mice were dosed intraperitoneally with 5, 15, 30, 40, or 50 mg/kg sarpogrelate 48, 24, and 0 hours prior to bright light exposure (10,000 lux) as well as 24 and 48 hours after exposure. Additionally, a single injection regimen was evaluated by injecting mice with 50 mg/kg sarpogrelate once immediately prior to light exposure. To investigate the potential for additive effects of serotonin receptor agents, a combination therapy consisting of sarpogrelate (15 mg/kg) and 8-OH-DPAT (1 mg/kg) was evaluated with the 5-day treatment regimen. Neuroprotection was characterized by the preservation of retinal thickness and function, measured by spectral-domain optical coherence tomography (SD-OCT) and electroretinography (ERG), respectively. RESULTS Mice that were light damaged and injected with saline had significantly reduced outer retinal thickness, total retinal thickness, and ERG amplitudes compared with naïve mice. A 5-day administration of 15, 30, or 40 mg/kg of sarpogrelate was able to partially protect retinal morphology and full protection of retinal morphology was achieved with a 50 mg/kg dose. Both 15 and 30 mg/kg doses of sarpogrelate partially preserved retinal function measured by ERG, whereas 40 and 50 mg/kg doses fully preserved retinal function. Additionally, a single administration of 50 mg/kg sarpogrelate was able to fully preserve both retinal morphology and function. Administration of 15 mg/kg of sarpogrelate and 1 mg/kg of 8-OH-DPAT together demonstrated an additive effect and fully preserved retinal morphology. CONCLUSIONS A 5- or 1-day treatment with 50 mg/kg sarpogrelate can completely protect the retina of BALB/c mice from light-induced retinopathy. Partial protection can be achieved with lower doses starting at 15 mg/kg and protection increases in a dose-dependent manner. Treatment with low doses of sarpogrelate and 8-OH-DPAT elicits an additive effect that results in full protection of retinal morphology.
Collapse
Affiliation(s)
- Brandon E Tullis
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Renee C Ryals
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Aaron S Coyner
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Michael J Gale
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Alex Nicholson
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Cristy Ku
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Dain Regis
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Wrik Sinha
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Shreya Datta
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Yuquan Wen
- Baylor University Medical Center, Dallas, Texas, United States
| | - Paul Yang
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| | - Mark E Pennesi
- Casey Eye Institute Oregon Health & Science University, Portland, Oregon, United States
| |
Collapse
|
7
|
Selective over-expression of endothelin-1 in endothelial cells exacerbates inner retinal edema and neuronal death in ischemic retina. PLoS One 2011; 6:e26184. [PMID: 22053184 PMCID: PMC3203861 DOI: 10.1371/journal.pone.0026184] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Accepted: 09/22/2011] [Indexed: 11/19/2022] Open
Abstract
The level of endothelin-1 (ET-1), a potent vasoconstrictor, was associated with retinopathy under ischemia. The effects of endothelial endothelin-1 (ET-1) over-expression in a transgenic mouse model using Tie-1 promoter (TET-1 mice) on pathophysiological changes of retinal ischemia were investigated by intraluminal insertion of a microfilament up to middle cerebral artery (MCA) to transiently block the ophthalmic artery. Two-hour occlusion and twenty-two-hour reperfusion were performed in homozygous (Hm) TET-1 mice and their non-transgenic (NTg) littermates. Presence of pyknotic nuclei in ganglion cell layer (GCL) was investigated in paraffin sections of ipsilateral (ischemic) and contralateral (non-ischemic) retinae, followed by measurement of the thickness of inner retinal layer. Moreover, immunocytochemistry of glial fibrillary acidic protein (GFAP), glutamine synthetase (GS) and aquaporin-4 (AQP4) peptides on retinal sections were performed to study glial cell reactivity, glutamate metabolism and water accumulation, respectively after retinal ischemia. Similar morphology was observed in the contralateral retinae of NTg and Hm TET-1 mice, whereas ipsilateral retina of NTg mice showed slight structural and cellular changes compared with the corresponding contralateral retina. Ipsilateral retinae of Hm TET-1 mice showed more significant changes when compared with ipsilateral retina of NTg mice, including more prominent cell death in GCL characterized by the presence of pyknotic nuclei, elevated GS immunoreactivity in Müller cell bodies and processes, increased AQP-4 immunoreactivity in Müller cell processes, and increased inner retinal thickness. Thus, over-expression of endothelial ET-1 in TET-1 mice may contribute to increased glutamate-induced neurotoxicity on neuronal cells and water accumulation in inner retina leading to edema.
Collapse
|
8
|
Abstract
Animal models are useful to elucidate the etiology and pathology of glaucoma and to develop novel and more effective therapies for the disease. Because of the substantial similarities between the rodent and primate eyes, and the advances of relevant study techniques, rat and mouse models of glaucoma have recently become popular as research tools. This review surveys research techniques used in the measurement of rodent intraocular pressure, and also the evaluation of pertinent morphologic, biochemical, and functional changes in the retina, optic nerve head, and optic nerve. This review further describes in detail the individual rodent models, some of which serve as surrogate models and do not entail ocular hypertension, whereas others involve transient or chronic increases of intraocular pressure. The technical considerations and theoretical concerns of these models, their advantages, and limitations, are also discussed.
Collapse
Affiliation(s)
- Iok-Hou Pang
- Glaucoma Research, Alcon Research, Ltd, Fort Worth, TX, USA.
| | | |
Collapse
|
9
|
Gastinger MJ, Tian N, Horvath T, Marshak DW. Retinopetal axons in mammals: emphasis on histamine and serotonin. Curr Eye Res 2006; 31:655-67. [PMID: 16877274 PMCID: PMC3351198 DOI: 10.1080/02713680600776119] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Since 1892, anatomical studies have demonstrated that the retinas of mammals, including humans, receive input from the brain via axons emerging from the optic nerve. There are only a small number of these retinopetal axons, but their branches in the inner retina are very extensive. More recently, the neurons in the brain stem that give rise to these axons have been localized, and their neurotransmitters have been identified. One set of retinopetal axons arises from perikarya in the posterior hypothalamus and uses histamine, and the other arises from perikarya in the dorsal raphe and uses serotonin. These serotonergic and histaminergic neurons are not specialized to supply the retina; rather, they are a subset of the neurons that project via collaterals to many other targets in the central nervous system, as well. They are components of the ascending arousal system, firing most rapidly when the animal is awake and active. The contributions of these retinopetal axons to vision may be predicted from the known effects of serotonin and histamine on retinal neurons. There is also evidence suggesting that retinopetal axons play a role in the etiology of retinal diseases.
Collapse
Affiliation(s)
- Matthew J Gastinger
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center Houston, Houston, Texas 77225, USA
| | | | | | | |
Collapse
|
10
|
Saito S, Ohashi M, Naito A, Fukaya Y, Suzuki Y, Araie M. Neuroprotective effect of the novel Na+/Ca2+ channel blocker NS-7 on rat retinal ganglion cells. Jpn J Ophthalmol 2005; 49:371-6. [PMID: 16187036 DOI: 10.1007/s10384-005-0210-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2004] [Accepted: 01/12/2005] [Indexed: 01/31/2023]
Abstract
PURPOSE To investigate whether NS-7, 4-(4-fluorophenyl)-2-methyl-6-(5-piperidinopentyloxy) pyrimidine hydrochloride, a novel Na(+)/Ca(2+) channel blocker, can protect the rat retina subjected to ischemia-reperfusion insult. METHODS To evaluate the protective effect of NS-7 against retinal damage, the drug was administered before and after ischemia-reperfusion. Damage to the retina was assessed by measuring the thickness of the inner plexiform layer (IPL) and the outer nuclear layer (ONL) of each eye. In a subsequent experiment, electroretinographic (ERG) evaluation was also used. RESULTS In histopathologic evaluation, ischemia-reperfusion injury caused a significant reduction of IPL thickness (measured as the IPL/ONL ratio). In the NS-7-treated group, retinal damage was partially prevented by a concentration of 0.25 mg/kg per day. In the ERG evaluation, ischemia-reperfusion injury caused a reduction of A- and B-wave amplitudes. NS-7 treatment significantly prevented the reduction of the B wave at a concentration of 0.1 or 0.3 mg/kg, while the reduction of the A wave was not significantly affected. CONCLUSIONS NS-7 has neuroprotective effects against retinal damage resulting from subjection to ischemia. In addition, NS-7 can be used as an agent for treating acute ischemic retinopathy, including diseases associated with very high intraocular pressure, such as acute angle-closure glaucoma.
Collapse
Affiliation(s)
- Shinichiro Saito
- Department of Ophthalmology, Nippon Medical School, Tokyo, Japan.
| | | | | | | | | | | |
Collapse
|
11
|
Linden R, Martins RAP, Silveira MS. Control of programmed cell death by neurotransmitters and neuropeptides in the developing mammalian retina. Prog Retin Eye Res 2004; 24:457-91. [PMID: 15845345 DOI: 10.1016/j.preteyeres.2004.10.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
It has long been known that a barrage of signals from neighboring and connecting cells, as well as components of the extracellular matrix, control cell survival. Given the extensive repertoire of retinal neurotransmitters, neuromodulators and neurotrophic factors, and the exhuberant interconnectivity of retinal interneurons, it is likely that various classes of released neuroactive substances may be involved in the control of sensitivity to retinal cell death. The aim of this article is to review evidence that neurotransmitters and neuropeptides control the sensitivity to programmed cell death in the developing retina. Whereas the best understood mechanism of execution of cell death is that of caspase-mediated apoptosis, current evidence shows that not only there are many parallel pathways to apoptotic cell death, but non-apoptotic programs of execution of cell death are also available, and may be triggered either in isolation or combined with apoptosis. The experimental data show that many upstream signaling pathways can modulate cell death, including those dependent on the second messengers cAMP-PKA, calcium and nitric oxide. Evidence for anterograde neurotrophic control is provided by a variety of models of the central nervous system, and the data reviewed here indicate that an early function of certain neurotransmitters, such as glutamate and dopamine, as well as neuropeptides such as pituitary adenylyl cyclase-activating polypeptide and vasoactive intestinal peptide is the trophic support of cell populations in the developing retina. This may have implications both regarding the mechanisms of retinal organogenesis, as well as pathological conditions leading to retinal dystrophies and to dysfunctional cellular behavior.
Collapse
Affiliation(s)
- Rafael Linden
- Centro de Ciencias da Saude, Instituto de Biofísica da UFRJ, Cidade Universitária, bloco G, Rio de Janeiro 21949-900, Brazil.
| | | | | |
Collapse
|
12
|
Osborne NN, Casson RJ, Wood JPM, Chidlow G, Graham M, Melena J. Retinal ischemia: mechanisms of damage and potential therapeutic strategies. Prog Retin Eye Res 2004; 23:91-147. [PMID: 14766318 DOI: 10.1016/j.preteyeres.2003.12.001] [Citation(s) in RCA: 737] [Impact Index Per Article: 36.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Retinal ischemia is a common cause of visual impairment and blindness. At the cellular level, ischemic retinal injury consists of a self-reinforcing destructive cascade involving neuronal depolarisation, calcium influx and oxidative stress initiated by energy failure and increased glutamatergic stimulation. There is a cell-specific sensitivity to ischemic injury which may reflect variability in the balance of excitatory and inhibitory neurotransmitter receptors on a given cell. A number of animal models and analytical techniques have been used to study retinal ischemia, and an increasing number of treatments have been shown to interrupt the "ischemic cascade" and attenuate the detrimental effects of retinal ischemia. Thus far, however, success in the laboratory has not been translated to the clinic. Difficulties with the route of administration, dosage, and adverse effects may render certain experimental treatments clinically unusable. Furthermore, neuroprotection-based treatment strategies for stroke have so far been disappointing. However, compared to the brain, the retina exhibits a remarkable natural resistance to ischemic injury, which may reflect its peculiar metabolism and unique environment. Given the increasing understanding of the events involved in ischemic neuronal injury it is hoped that clinically effective treatments for retinal ischemia will soon be available.
Collapse
Affiliation(s)
- Neville N Osborne
- Nuffield Laboratory of Ophthalmology, University of Oxford, Walton Street, Oxford OX2 6AW, UK.
| | | | | | | | | | | |
Collapse
|