1
|
Wu LH, Cheng YW, Lin FL, Hsu KC, Wang MH, Yen JL, Wang TJ, Lin TE, Liu YC, Huang WJ, Hsiao G. A novel HDAC8 inhibitor H7E exerts retinoprotective effects against glaucomatous injury via ameliorating aberrant Müller glia activation and oxidative stress. Biomed Pharmacother 2024; 174:116538. [PMID: 38579401 DOI: 10.1016/j.biopha.2024.116538] [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] [Received: 01/05/2024] [Revised: 03/18/2024] [Accepted: 03/29/2024] [Indexed: 04/07/2024] Open
Abstract
Glaucoma is considered a neurodegenerative disease characterized by progressive visual field defects that may lead to blindness. Although controlling intraocular pressure (IOP) is the mainstay of glaucoma treatment, some glaucoma patients have unmet needs due to unclear pathogenic mechanisms. Recently, there has been growing evidence that neuroinflammation is a potential target for the development of novel antiglaucoma agents. In this study, we investigated the protective effects and cellular mechanisms of H7E, a novel small molecule inhibits HDAC8, using in vitro and in vivo glaucoma-like models. Importantly, H7E mitigated extracellular MMP-9 activity and MCP-1 levels in glutamate- or S100B-stimulated reactive Müller glia. In addition, H7E inhibited the upregulation of inflammation- and proliferation-related signaling pathways, particularly the ERK and JNK MAPK pathways. Under conditions of oxidative damage, H7E prevents retinal cell death and reduces extracellular glutamate released from stressed Müller glia. In a mouse model of NMDA-induced retinal degeneration, H7E alleviated functional and structural defects within the inner retina as assessed by electroretinography and optical coherence tomography. Our results demonstrated that the newly identified compound H7E protects against glaucoma damage by specifically targeting HDAC8 activity in the retina. This protective effect is attributed to the inhibition of Müller glial activation and the prevention of retinal cell death caused by oxidative stress.
Collapse
Affiliation(s)
- Liang-Huan Wu
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - Yu-Wen Cheng
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan; Department of Pharmaceutical Sciences, School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - Fan-Li Lin
- Department of Pharmacology, School of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., Kaohsiung 807, Taiwan.
| | - Kai-Cheng Hsu
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan; Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, 301 Yuantong Rd., New Taipei 235, Taiwan.
| | - Mong-Heng Wang
- Independent Scholar, 3466 Rhodes Hill Drive, Martinez, GA 30907, USA.
| | - Jing-Lun Yen
- Graduate Institute of Medical Sciences and Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - Tsung-Jen Wang
- Department of Ophthalmology, Taipei Medical University Hospital, 252 Wu-Hsing St., Taipei 110, Taiwan; Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - Tony Eight Lin
- Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, 301 Yuantong Rd., New Taipei 235, Taiwan.
| | - Yi-Chien Liu
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - Wei-Jan Huang
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan; Department of Pharmaceutical Sciences, School of Pharmacy, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| | - George Hsiao
- Ph.D. Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan; Graduate Institute of Medical Sciences and Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan; Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, 250 Wu-Hsing St., Taipei 110, Taiwan.
| |
Collapse
|
2
|
Feng L, Wang C, Zhang C, Zhang W, Song W. Role of epigenetic regulation in glaucoma. Biomed Pharmacother 2023; 168:115633. [PMID: 37806089 DOI: 10.1016/j.biopha.2023.115633] [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] [Received: 08/16/2023] [Revised: 09/23/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023] Open
Abstract
Glaucoma is the world's leading irreversible blinding eye disease. Lowering intraocular pressure is currently the only effective clinical treatment. However, there is a lack of long-acting IOP-lowering drugs, and some patients still experience retinal ganglion cell loss even with good intraocular pressure control. Currently, there is no effective method for neuroprotection and regeneration in clinical practice for glaucoma. In recent years, epigenetics has been widely researched and reported for its role in glaucoma's neuroprotection and regeneration. This article reviews the changes in histone modifications, DNA methylation, non-coding RNA, and m6A methylation in glaucoma, aiming to provide new perspectives for glaucoma management, protection of retinal ganglion cells, and axon regeneration by understanding epigenetic alterations.
Collapse
Affiliation(s)
- Lemeng Feng
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Chao Wang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Cheng Zhang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Wulong Zhang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China
| | - Weitao Song
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital of Central South University, Changsha, Hunan 410008, PR China; Eye Center of Xiangya Hospital, Central South University, Changsha, Hunan 410008, PR China; Hunan Key Laboratory of Ophthalmology, Changsha, Hunan 410008, PR China.
| |
Collapse
|
3
|
Lo J, Mehta K, Dhillon A, Huang YK, Luo Z, Nam MH, Al Diri I, Chang KC. Therapeutic strategies for glaucoma and optic neuropathies. Mol Aspects Med 2023; 94:101219. [PMID: 37839232 PMCID: PMC10841486 DOI: 10.1016/j.mam.2023.101219] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 10/02/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023]
Abstract
Glaucoma is a neurodegenerative eye disease that causes permanent vision impairment. The main pathological characteristics of glaucoma are retinal ganglion cell (RGC) loss and optic nerve degeneration. Glaucoma can be caused by elevated intraocular pressure (IOP), although some cases are congenital or occur in patients with normal IOP. Current glaucoma treatments rely on medicine and surgery to lower IOP, which only delays disease progression. First-line glaucoma medicines are supported by pharmacotherapy advancements such as Rho kinase inhibitors and innovative drug delivery systems. Glaucoma surgery has shifted to safer minimally invasive (or microinvasive) glaucoma surgery, but further trials are needed to validate long-term efficacy. Further, growing evidence shows that adeno-associated virus gene transduction and stem cell-based RGC replacement therapy hold potential to treat optic nerve fiber degeneration and glaucoma. However, better understanding of the regulatory mechanisms of RGC development is needed to provide insight into RGC differentiation from stem cells and help choose target genes for viral therapy. In this review, we overview current progress in RGC development research, optic nerve fiber regeneration, and human stem cell-derived RGC differentiation and transplantation. We also provide an outlook on perspectives and challenges in the field.
Collapse
Affiliation(s)
- Jung Lo
- Department of Ophthalmology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, 83301, Taiwan
| | - Kamakshi Mehta
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA
| | - Armaan Dhillon
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Yu-Kai Huang
- Department of Neurosurgery, Kaohsiung Medical University Hospital, Kaohsiung, 80708, Taiwan; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan
| | - Ziming Luo
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, 94304, USA
| | - Mi-Hyun Nam
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, 80045, USA.
| | - Issam Al Diri
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA.
| | - Kun-Che Chang
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15219, USA; Department of Neurobiology, Center of Neuroscience, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA; Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, 80708, Taiwan.
| |
Collapse
|
4
|
Pan F, Hu D, Sun LJ, Bai Q, Wang YS, Hou X. Valproate reduces retinal ganglion cell apoptosis in rats after optic nerve crush. Neural Regen Res 2023; 18:1607-1612. [PMID: 36571369 PMCID: PMC10075129 DOI: 10.4103/1673-5374.357913] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The retinal ganglion cells of the optic nerve have a limited capacity for self-repair after injury. Valproate is a histone deacetylase inhibitor and multitarget drug, which has been demonstrated to protect retinal neurons. In this study, we established rat models of optic nerve-crush injury and injected valproate into the vitreous cavity immediately after modeling. We evaluated changes in the ultrastructure morphology of the endoplasmic reticulum of retinal ganglion cells over time via transmission electron microscope. Immunohistochemistry and western blot assay revealed that valproate upregulated the expression of the endoplasmic reticulum stress marker glucose-regulated protein 78 and downregulated the expression of transcription factor C/EBP homologous protein, phosphorylated eukaryotic translation initiation factor 2α, and caspase-12 in the endoplasmic reticulum of retinal ganglion cells. These findings suggest that valproate reduces apoptosis of retinal ganglion cells in the rat after optic nerve-crush injury by attenuating phosphorylated eukaryotic translation initiation factor 2α-C/EBP homologous protein signaling and caspase-12 activation during endoplasmic reticulum stress. These findings represent a newly discovered mechanism that regulates how valproate protects neurons.
Collapse
Affiliation(s)
- Feng Pan
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Dan Hu
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Li-Juan Sun
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Qian Bai
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Yu-Sheng Wang
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| | - Xu Hou
- Eye Institute of Chinese PLA and Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China
| |
Collapse
|
5
|
Tawarayama H, Hirata Y, Uchida K, Himori N, Uesato S, Nakazawa T. Isozyme-specific histone deacetylase 1/2 inhibitor K560 attenuates oxidative stress-induced retinal cell death. Neurosci Lett 2023; 793:136978. [PMID: 36435210 DOI: 10.1016/j.neulet.2022.136978] [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: 07/05/2022] [Revised: 10/23/2022] [Accepted: 11/20/2022] [Indexed: 11/24/2022]
Abstract
Oxidative stress-induced damage is an underlying mechanism in the pathogenesis of age-related retinal diseases. Here, we examined the effects of K560, a potential candidate drug for the treatment of these diseases, on oxidative stress-induced retinal cell death. K560 is a novel isozyme-specific inhibitor of histone deacetylase 1 and 2 (HDAC1/2). Histone acetylation in retinal lysates and dissociated retinal cells was detected with a western blot analysis and cell-based enzyme-linked immunosorbent assay (ELISA), respectively. The viability of mouse retinal cells was measured with an alamarBlue assay. We used immunohistochemistry for RNA binding protein with multiple splicing (RBPMS) to visualize the retinal ganglion cells (RGCs) of mice. An ELISA analysis indicated that histone acetylation was enhanced in dissociated mouse retinal cells treated with K560. The cell viability assay indicated that K560 attenuated both exogenous hydrogen peroxide-induced and endogenous oxidative stress-induced cell death in dissociated retinal cells. Western blot analysis indicated that intravitreal K560 administration enhanced the acetylation of histones H3 and H4 in mouse retinal lysates. To examine the effect of K560 on oxidative stress-induced RGC death, we performed whole-mount immunohistochemistry for RBPMS on retinas dissected from eyes treated with K560 or vehicle on day one, and K560 or vehicle and NMDA on day two. Quantification of RBPMS-immunopositive cells indicated that K560 attenuated NMDA-induced RGC death. Taken together, our findings suggest that administration of a HDAC1/2-specific inhibitor K560 may be effective in the treatment of oxidative stress-mediated retinal degeneration and have less cytotoxicity than other known HDAC inhibitors, which are known to target a wide range of HDAC family members.
Collapse
Affiliation(s)
- Hiroshi Tawarayama
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan.
| | - Yoshiyuki Hirata
- Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
| | - Keiko Uchida
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan
| | - Noriko Himori
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Aging Vision Healthcare, Tohoku University Graduate School of Biomedical Engineering, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Shinichi Uesato
- Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan.
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan; Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8575, Japan.
| |
Collapse
|
6
|
Liu S, Tian H, Niu Y, Yu C, Xie L, Jin Z, Niu W, Ren J, Fu L, Yao Z. Combined cell grafting and VPA administration facilitates neural repair through axonal regeneration and synaptogenesis in traumatic brain injury. Acta Biochim Biophys Sin (Shanghai) 2022; 54:1289-1300. [PMID: 36148950 PMCID: PMC9828309 DOI: 10.3724/abbs.2022123] [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] [Indexed: 12/29/2022] Open
Abstract
Neuronal regeneration and functional recovery are severely compromised following traumatic brain injury (TBI). Treatment options, including cell transplantation and drug therapy, have been shown to benefit TBI, although the underlying mechanisms remain elusive. In this study, neural stem cells (NSCs) are transplanted into TBI-challenged mice, together with olfactory ensheathing cells (OECs) or followed by valproic acid (VPA) treatment. Both OEC grafting and VPA treatment facilitate the differentiation of NSCs into neurons (including endogenous and exogenous neurons) and significantly attenuate neurological functional defects in TBI mice. Combination of NSCs with OECs or VPA administration leads to overt improvement in axonal regeneration, synaptogenesis, and synaptic plasticity in the cerebral cortex in TBI-challenged mice, as shown by retrograde corticospinal tract tracing, electron microscopy, growth-associated protein 43 (GAP43), and synaptophysin (SYN) analyses. However, these beneficial effects of VPA are reversed by local delivery of N-methyl-D-aspartate (NMDA) into tissues surrounding the injury epicenter in the cerebral cortex, accompanied by a pronounced drop in axons and synapses in the brain. Our findings reveal that increased axonal regeneration and synaptogenesis evoked by cell grafting and VPA fosters neural repair in a murine model of TBI. Moreover, VPA-induced neuroprotective roles are antagonized by exogenous NMDA administration and its concomitant decrease in the number of neurons of local brain, indicating that increased neurons induced by VPA treatment mediate axonal regeneration and synaptogenesis in mice after TBI operation. Collectively, this study provides new insights into NSC transplantation therapy for TBI.
Collapse
Affiliation(s)
- Sujuan Liu
- Department of Anatomy and EmbryologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China
| | - Haili Tian
- School of KinesiologyShanghai University of SportShanghai200438China
| | - Yanmei Niu
- Department of RehabilitationSchool of Medical TechnologyTianjin Medical UniversityTianjin300070China
| | - Chunxia Yu
- Department of Physiology and PathophysiologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China
| | - Lingjian Xie
- Department of Physiology and PathophysiologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China
| | - Zhe Jin
- Tianjin Yaohua Binhai SchoolTianjin300000China
| | - Wenyan Niu
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education)Department of ImmunologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China
| | - Jun Ren
- Department of CardiologyZhongshan Hospital Fudan UniversityShanghai Institute of Cardiovascular DiseasesShanghai200032China,Department of Laboratory Medicine and PathologyUniversity of WashingtonSeattleWA98195USA,Correspondence address. Tel: +86-22-83336819; (Z.Y.) / Tel: +86-22-83336107; (L.F.) / Tel: +86-21-64041990; (J.R.) @
| | - Li Fu
- Department of RehabilitationSchool of Medical TechnologyTianjin Medical UniversityTianjin300070China,Department of Physiology and PathophysiologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China,Correspondence address. Tel: +86-22-83336819; (Z.Y.) / Tel: +86-22-83336107; (L.F.) / Tel: +86-21-64041990; (J.R.) @
| | - Zhi Yao
- Key Laboratory of Immune Microenvironment and Disease (Ministry of Education)Department of ImmunologySchool of Basic Medical ScienceTianjin Medical UniversityTianjin300070China,Correspondence address. Tel: +86-22-83336819; (Z.Y.) / Tel: +86-22-83336107; (L.F.) / Tel: +86-21-64041990; (J.R.) @
| |
Collapse
|
7
|
Sharif NA. Therapeutic Drugs and Devices for Tackling Ocular Hypertension and Glaucoma, and Need for Neuroprotection and Cytoprotective Therapies. Front Pharmacol 2021; 12:729249. [PMID: 34603044 PMCID: PMC8484316 DOI: 10.3389/fphar.2021.729249] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 08/18/2021] [Indexed: 12/11/2022] Open
Abstract
Damage to the optic nerve and the death of associated retinal ganglion cells (RGCs) by elevated intraocular pressure (IOP), also known as glaucoma, is responsible for visual impairment and blindness in millions of people worldwide. The ocular hypertension (OHT) and the deleterious mechanical forces it exerts at the back of the eye, at the level of the optic nerve head/optic disc and lamina cribosa, is the only modifiable risk factor associated with glaucoma that can be treated. The elevated IOP occurs due to the inability of accumulated aqueous humor (AQH) to egress from the anterior chamber of the eye due to occlusion of the major outflow pathway, the trabecular meshwork (TM) and Schlemm’s canal (SC). Several different classes of pharmaceutical agents, surgical techniques and implantable devices have been developed to lower and control IOP. First-line drugs to promote AQH outflow via the uveoscleral outflow pathway include FP-receptor prostaglandin (PG) agonists (e.g., latanoprost, travoprost and tafluprost) and a novel non-PG EP2-receptor agonist (omidenepag isopropyl, Eybelis®). TM/SC outflow enhancing drugs are also effective ocular hypotensive agents (e.g., rho kinase inhibitors like ripasudil and netarsudil; and latanoprostene bunod, a conjugate of a nitric oxide donor and latanoprost). One of the most effective anterior chamber AQH microshunt devices is the Preserflo® microshunt which can lower IOP down to 10–13 mmHg. Other IOP-lowering drugs and devices on the horizon will be also discussed. Additionally, since elevated IOP is only one of many risk factors for development of glaucomatous optic neuropathy, a treatise of the role of inflammatory neurodegeneration of the optic nerve and retinal ganglion cells and appropriate neuroprotective strategies to mitigate this disease will also be reviewed and discussed.
Collapse
Affiliation(s)
- Najam A Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
| |
Collapse
|
8
|
DZNep protects against retinal ganglion cell death in an NMDA-induced mouse model of retinal degeneration. Exp Eye Res 2021; 212:108785. [PMID: 34600894 DOI: 10.1016/j.exer.2021.108785] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/10/2021] [Accepted: 09/28/2021] [Indexed: 02/08/2023]
Abstract
Epigenetic gene enhancer of zeste homolog-2 (Ezh2) is reported to be associated with ocular neurodegenerative diseases; however, its underlying mechanism is poorly understood. The present study aimed to determine the role of 3-deazaneplanocin A (DZNep), which inhibits the transcription of Ezh2 by reducing the trimethylation of histone 3 lysine 27 (H3K27me3), in a retinal ganglion cell (RGC) degeneration model. Retinal damage was caused by intravitreal injection of N-methyl-D-aspartate (NMDA). DZNep and the vehicle control were intravitreally applied immediately post-NMDA injection. The severity of retinal damage was evaluated by immunofluorescence and terminal deoxyribonucleotide transferase (TdT)-mediated dUTP nick end labeling (TUNEL) staining, and retinal function was determined by electroretinogram (ERG). The transcriptome was examined by RNA sequencing and quantitative PCR (qPCR). Microglial cells were detected by immunohistochemistry. DZNep significantly prevented the cell death in the ganglion cell layer (GCL) and inner nuclear layer (INL) induced by NMDA. DZNep preserved the ERG b- and a-wave amplitudes and the b/a ratio in NMDA-treated mice. Moreover, RNA sequencing and qPCR revealed that neuroprotective genes were upregulated and played an important role in preserving retinal cells. In addition, DZNep inhibited the NMDA-induced activation of microglial cells. Our results suggest that H3K27me3 controls RGC survival at the transcriptional and epigenetic levels. The absence of H3K27me3 deposition upregulates neuroprotective genes to protect RGCs. Therefore, DZNep, which inhibits Ezh2 activity, could be a novel therapeutic treatment for ocular neurodegenerative diseases.
Collapse
|
9
|
Visual Disfunction due to the Selective Effect of Glutamate Agonists on Retinal Cells. Int J Mol Sci 2021; 22:ijms22126245. [PMID: 34200611 PMCID: PMC8230349 DOI: 10.3390/ijms22126245] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/25/2021] [Accepted: 05/30/2021] [Indexed: 02/07/2023] Open
Abstract
One of the causes of nervous system degeneration is an excess of glutamate released upon several diseases. Glutamate analogs, like N-methyl-DL-aspartate (NMDA) and kainic acid (KA), have been shown to induce experimental retinal neurotoxicity. Previous results have shown that NMDA/KA neurotoxicity induces significant changes in the full field electroretinogram response, a thinning on the inner retinal layers, and retinal ganglion cell death. However, not all types of retinal neurons experience the same degree of injury in response to the excitotoxic stimulus. The goal of the present work is to address the effect of intraocular injection of different doses of NMDA/KA on the structure and function of several types of retinal cells and their functionality. To globally analyze the effect of glutamate receptor activation in the retina after the intraocular injection of excitotoxic agents, a combination of histological, electrophysiological, and functional tools has been employed to assess the changes in the retinal structure and function. Retinal excitotoxicity caused by the intraocular injection of a mixture of NMDA/KA causes a harmful effect characterized by a great loss of bipolar, amacrine, and retinal ganglion cells, as well as the degeneration of the inner retina. This process leads to a loss of retinal cell functionality characterized by an impairment of light sensitivity and visual acuity, with a strong effect on the retinal OFF pathway. The structural and functional injury suffered by the retina suggests the importance of the glutamate receptors expressed by different types of retinal cells. The effect of glutamate agonists on the OFF pathway represents one of the main findings of the study, as the evaluation of the retinal lesions caused by excitotoxicity could be specifically explored using tests that evaluate the OFF pathway.
Collapse
|
10
|
Retinal structural changes in mood disorders: The optical coherence tomography to better understand physiopathology? Prog Neuropsychopharmacol Biol Psychiatry 2021; 108:110080. [PMID: 32827610 DOI: 10.1016/j.pnpbp.2020.110080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND Mood disorders are particularly common, disabling conditions. Diagnosis can be difficult as it may involve different pathophysiological assumptions. This could explain why such disorders are resistant to treatment. The retina is part of the central nervous system and shares a common embryonic origin with the brain. Optical coherence tomography (OCT) is an imaging technique for analysing the different layers of the retina. We reviewed studies that examined the retina with OCT in mood disorders. METHODS We conducted Pubmed search and additional manual research based on the bibliography in each of selected articles. We found and analysed 11 articles relevant to our subject. RESULTS This literature review confirms that it is possible to use OCT to detect neurodegeneration and neuroinflammation in mood disorders. Their impact is thought to depend on the duration and severity of the disease, and whether it is in acute or chronic stage. The differences seen in studies dealing with depression and those looking at bipolar disorder may reflect the particular characteristics of each disorder. A number of OCT parameters can be proposed as biomarkers of active or chronic inflammation and neurodegeneration. Markers of predisposition to an at-risk mental state are also suggested. LIMITATIONS The main limitation is selection bias, studies including more varied population would help to confirm and precise these results. CONCLUSION OCT is thus a particularly promising tool for evaluating some of the etiopathogenetic mechanisms involved in mood disorders. The combination with other approaches could help to find more specific biomarkers.
Collapse
|
11
|
Zaidi SAH, Thakore N, Singh S, Guzman W, Mehrotra S, Gangaraju V, Husain S. Histone Deacetylases Regulation by δ-Opioids in Human Optic Nerve Head Astrocytes. Invest Ophthalmol Vis Sci 2021; 61:17. [PMID: 32915982 PMCID: PMC7488628 DOI: 10.1167/iovs.61.11.17] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Purpose We determined whether δ-opioid receptor agonist (SNC-121) regulates acetylation homeostasis via controlling histone deacetylases (HDACs) activity and expression in optic nerve head (ONH) astrocytes. Methods ONH astrocytes were treated with SNC-121 (1 µM) for 24 hours. The HDAC activity was measured using HDAC-specific fluorophore-conjugated synthetic substrates, Boc-Lys(Ac)-AMC and (Boc-Lys(Tfa)-AMC). Protein and mRNA expression of each HDAC was determined by Western blotting and quantitative real-time PCR. IOP in rats was elevated by injecting 2.0 M hypertonic saline into the limbal veins. Results Delta opioid receptor agonist, SNC-121 (1 µM), treatment increased acetylation of histone H3, H2B, and H4 by 128 ± 3%, 45 ± 1%, and 68 ± 2%, respectively. The addition of Garcinol, a histone-acetyltransferase inhibitor, fully blocked SNC-121–induced histone H3 acetylation. SNC-121 reduced the activities of class I and IIb HDACs activities significantly (17 ± 3%) and this decrease in HDACs activities was fully blocked by a selective δ-opioid receptors antagonist, naltrindole. SNC-121 also decrease the mRNA expression of HDAC-3 and HDAC-6 by 19% and 18%, respectively. Furthermore, protein expression of HDAC 1, 2, 3, and 6 was significantly (P < 0.05) decreased by SNC-121 treatment. SNC-121 treatment also reduced lipopolysaccharide-induced TNF-α production from ONH astrocytes and glial fibrillary acidic protein immunostaining in the optic nerve of ocular hypertensive animals. Conclusions We provided evidence that δ-opioid receptor agonist activation increased histone acetylation, decrease HDACs class I and class IIb activities, mRNA, and protein expression, lipopolysaccharide-induced TNF-α production in ONH astrocytes. Our data also demonstrate that SNC-121 treatment decrease glial fibrillary acidic protein immunostaining in the optic nerves of animals with ocular hypertension.
Collapse
Affiliation(s)
- Syed A H Zaidi
- Hewitt Laboratory of the Ola B. Williams Glaucoma Centre, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Nakul Thakore
- Hewitt Laboratory of the Ola B. Williams Glaucoma Centre, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Sudha Singh
- Hewitt Laboratory of the Ola B. Williams Glaucoma Centre, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Wendy Guzman
- Hewitt Laboratory of the Ola B. Williams Glaucoma Centre, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Shikhar Mehrotra
- Department of Surgery, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina
| | - Vamsi Gangaraju
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina
| | - Shahid Husain
- Hewitt Laboratory of the Ola B. Williams Glaucoma Centre, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina
| |
Collapse
|
12
|
Chen X, Di H, Hong Y, Zhang C. Late-stage sequela of an isolated optic neuropathy after acute magnesium valproate overdose: A case report. Eur J Ophthalmol 2020; 32:1120672120974943. [PMID: 33222509 DOI: 10.1177/1120672120974943] [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] [Indexed: 11/16/2022]
Abstract
BACKGROUND Magnesium valproate is a valproic acid (VPA) derivative that is widely used for the treatment of epilepsy and bipolar disorders. Acute overdose of VPA may cause complicated systemic syndromes; however, the reports of ocular sequelae caused by toxic optic neuropathy (TON) are rare. CASE PRESENTATION We present a case of a 19-year-old female with bilateral damage to visual function after acute VPA overdose. She was comatose and received systemic treatments for 1 month, during which she suffered a substantial loss of visual function without any evident neurological sequelae. The first recorded visual acuity was no light perception in the right eye (OD) and hand motion in the left eye (OS). Her best-corrected visual acuity improved to 20/100 OS after 4 months of hyperbaric oxygen therapy and neurotrophic treatments. Her visual field was limited to an inferior nasal area OS. Therefore, a diagnosis of TON was made. Her visual function remained stable in the left eye, but did not recover in the right eye during the 5-month follow-up. We found damage to the optic nerve pathway during ophthalmic examinations. CONCLUSION We report a rare case of TON caused by acute VPA overdose. Hyperbaric oxygen therapy, and neuroprotective and neurotrophic treatments might be effective at the early stage but cannot fully reverse the damage to the optic nerve. The present case indicates the potential neurotoxicity of VPA. It is crucial to determine the severity of an isolated optic nerve sequela caused by VPA overdose, though it might be rare as observed in previous reports. Further confirmation of the likelihood of its causation and its pathophysiology is needed in the future.
Collapse
Affiliation(s)
- Xuhao Chen
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Haohao Di
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
- Department of Ophthalmology, Zhengzhou Second Hospital, Henan, China
| | - Ying Hong
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| | - Chun Zhang
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
- Beijing Key Laboratory of Restoration of Damaged Ocular Nerve, Peking University Third Hospital, Beijing, China
| |
Collapse
|
13
|
Suppression of Oxidative Stress as Potential Therapeutic Approach for Normal Tension Glaucoma. Antioxidants (Basel) 2020; 9:antiox9090874. [PMID: 32947996 PMCID: PMC7554707 DOI: 10.3390/antiox9090874] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/11/2020] [Accepted: 09/14/2020] [Indexed: 12/12/2022] Open
Abstract
Glaucoma is a neurodegenerative disease of the eye, which involves degeneration of retinal ganglion cells (RGCs): the output neurons of the retina to the brain, which with their axons comprise the optic nerve. Recent studies have shown the possible involvement of oxidative stress in the pathogenesis of glaucoma, especially in the subtype of normal tension glaucoma. Basic experiments utilizing rodent and primate models of glaucoma revealed that antioxidants protect RGCs under various pathological conditions including glutamate neurotoxicity and optic nerve injury. These results suggested that existing drugs and food factors may be useful for prevention and hence therapy of glaucoma. In this review, we highlight some therapeutic candidates, particularly those with antioxidant properties, and discuss the therapeutic potential of RGC protection by modulating gene expressions that prevent and ameliorate glaucoma.
Collapse
|
14
|
Calvo E, Milla-Navarro S, Ortuño-Lizarán I, Gómez-Vicente V, Cuenca N, De la Villa P, Germain F. Deleterious Effect of NMDA Plus Kainate on the Inner Retinal Cells and Ganglion Cell Projection of the Mouse. Int J Mol Sci 2020; 21:ijms21051570. [PMID: 32106602 PMCID: PMC7084685 DOI: 10.3390/ijms21051570] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 02/21/2020] [Accepted: 02/22/2020] [Indexed: 12/24/2022] Open
Abstract
Combined administration of N-Methyl-D-Aspartate (NMDA) and kainic acid (KA) on the inner retina was studied as a model of excitotoxicity. The right eye of C57BL6J mice was injected with 1 µL of PBS containing NMDA 30 mM and KA 10 mM. Only PBS was injected in the left eye. One week after intraocular injection, electroretinogram recordings and immunohistochemistry were performed on both eyes. Retinal ganglion cell (RGC) projections were studied by fluorescent-cholerotoxin anterograde labeling. A clear decrease of the retinal "b" wave amplitude, both in scotopic and photopic conditions, was observed in the eyes injected with NMDA/KA. No significant effect on the "a" wave amplitude was observed, indicating the preservation of photoreceptors. Immunocytochemical labeling showed no effects on the outer nuclear layer, but a significant thinning on the inner retinal layers, thus indicating that NMDA and KA induce a deleterious effect on bipolar, amacrine and ganglion cells. Anterograde tracing of the visual pathway after NMDA and KA injection showed the absence of RGC projections to the contralateral superior colliculus and lateral geniculate nucleus. We conclude that glutamate receptor agonists, NMDA and KA, induce a deleterious effect of the inner retina when injected together into the vitreous chamber.
Collapse
Affiliation(s)
- Estrella Calvo
- Department of Systems Biology, University of Alcalá, 28871 Madrid, Spain (P.D.l.V.)
| | | | - Isabel Ortuño-Lizarán
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690 Alicante, Spain
| | - Violeta Gómez-Vicente
- Department of Optics, Pharmacology and Anatomy, University of Alicante, 03690 Alicante, Spain;
| | - Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690 Alicante, Spain
| | - Pedro De la Villa
- Department of Systems Biology, University of Alcalá, 28871 Madrid, Spain (P.D.l.V.)
- Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), 28034 Madrid, Spain
| | - Francisco Germain
- Department of Systems Biology, University of Alcalá, 28871 Madrid, Spain (P.D.l.V.)
- Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS), 28034 Madrid, Spain
- Correspondence:
| |
Collapse
|
15
|
Birch DG, Bernstein PS, Iannacone A, Pennesi ME, Lam BL, Heckenlively J, Csaky K, Hartnett ME, Winthrop KL, Jayasundera T, Hughbanks-Wheaton DK, Warner J, Yang P, Fish GE, Teske MP, Sklaver NL, Erker L, Chegarnov E, Smith T, Wahle A, VanVeldhuisen PC, McCormack J, Lindblad R, Bramer S, Rose S, Zilliox P, Francis PJ, Weleber RG. Effect of Oral Valproic Acid vs Placebo for Vision Loss in Patients With Autosomal Dominant Retinitis Pigmentosa: A Randomized Phase 2 Multicenter Placebo-Controlled Clinical Trial. JAMA Ophthalmol 2019; 136:849-856. [PMID: 29879277 DOI: 10.1001/jamaophthalmol.2018.1171] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Importance There are no approved drug treatments for autosomal dominant retinitis pigmentosa, a relentlessly progressive cause of adult and childhood blindness. Objectives To evaluate the potential efficacy and assess the safety of orally administered valproic acid (VPA) in the treatment of autosomal dominant retinitis pigmentosa. Design, Setting, and Participants Multicenter, phase 2, prospective, interventional, placebo-controlled, double-masked randomized clinical trial. The study took place in 6 US academic retinal degeneration centers. Individuals with genetically characterized autosomal dominant retinitis pigmentosa were randomly assigned to receive treatment or placebo for 12 months. Analyses were intention-to-treat. Interventions Oral VPA 500 mg to 1000 mg daily for 12 months or placebo. Main Outcomes and Measures The primary outcome measure was determined prior to study initiation as the change in visual field area (assessed by the III4e isopter, semiautomated kinetic perimetry) between baseline and month 12. Results The mean (SD) age of the 90 participants was 50.4 (11.6) years. Forty-four (48.9%) were women, 87 (96.7%) were white, and 79 (87.8%) were non-Hispanic. Seventy-nine participants (87.8%) completed the study (42 [95.5%] received placebo and 37 [80.4%] received VPA). Forty-two (46.7%) had a rhodopsin mutation. Most adverse events were mild, although 7 serious adverse events unrelated to VPA were reported. The difference between the VPA and placebo arms for mean change in the primary outcome was -150.43 degree2 (95% CI, -290.5 to -10.03; P = .035). Conclusions and Relevance This negative value indicates that the VPA arm had worse outcomes than the placebo group. This study brings to light the key methodological considerations that should be applied to the rigorous evaluation of treatments for these conditions. This study does not provide support for the use of VPA in the treatment of autosomal dominant retinitis pigmentosa. Trial Registration ClinicalTrials.gov Identifier: NCT01233609.
Collapse
Affiliation(s)
| | | | - Alessandro Iannacone
- University of Tennessee Health Sciences Center, Hamilton Eye Institute, Memphis.,now with Duke University School of Medicine, Duke Eye Center, Durham, North Carolina
| | - Mark E Pennesi
- Oregon Health & Science University, Casey Eye Institute, Portland
| | - Byron L Lam
- University of Miami, Bascom Palmer Eye Institute, Miami, Florida
| | | | - Karl Csaky
- Retina Foundation of the Southwest, Dallas, Texas
| | | | - Kevin L Winthrop
- now with Duke University School of Medicine, Duke Eye Center, Durham, North Carolina
| | | | | | - Judith Warner
- University of Utah School of Medicine, Salt Lake City
| | - Paul Yang
- Oregon Health & Science University, Casey Eye Institute, Portland
| | | | | | | | - Laura Erker
- Oregon Health & Science University, Casey Reading Center, Portland
| | - Elvira Chegarnov
- Oregon Health & Science University, Casey Reading Center, Portland
| | - Travis Smith
- Oregon Health & Science University, Casey Reading Center, Portland
| | | | | | | | | | | | - Stephen Rose
- Foundation Fighting Blindness, Columbia, Maryland
| | | | | | | |
Collapse
|
16
|
Honda S, Namekata K, Kimura A, Guo X, Harada C, Murakami A, Matsuda A, Harada T. Survival of Alpha and Intrinsically Photosensitive Retinal Ganglion Cells in NMDA-Induced Neurotoxicity and a Mouse Model of Normal Tension Glaucoma. ACTA ACUST UNITED AC 2019; 60:3696-3707. [DOI: 10.1167/iovs.19-27145] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Sari Honda
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
- Department of Ophthalmology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Akira Murakami
- Department of Ophthalmology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Akira Matsuda
- Department of Ophthalmology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| |
Collapse
|
17
|
Assessing retinal ganglion cell death and neuroprotective agents using real time imaging. Brain Res 2019; 1714:65-72. [DOI: 10.1016/j.brainres.2019.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 02/07/2019] [Accepted: 02/08/2019] [Indexed: 01/01/2023]
|
18
|
Christensen I, Lu B, Yang N, Huang K, Wang P, Tian N. The Susceptibility of Retinal Ganglion Cells to Glutamatergic Excitotoxicity Is Type-Specific. Front Neurosci 2019; 13:219. [PMID: 30930737 PMCID: PMC6429039 DOI: 10.3389/fnins.2019.00219] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 02/26/2019] [Indexed: 12/17/2022] Open
Abstract
Retinal ganglion cells (RGCs) are the only output neurons that conduct visual signals from the eyes to the brain. RGC degeneration occurs in many retinal diseases leading to blindness and increasing evidence suggests that RGCs are susceptible to various injuries in a type-specific manner. Glutamate excitotoxicity is the pathological process by which neurons are damaged and killed by excessive stimulation of glutamate receptors and it plays a central role in the death of neurons in many CNS and retinal diseases. The purpose of this study is to characterize the susceptibility of genetically identified RGC types to the excitotoxicity induced by N-methyl-D-aspartate (NMDA). We show that the susceptibility of different types of RGCs to NMDA excitotoxicity varies significantly, in which the αRGCs are the most resistant type of RGCs to NMDA excitotoxicity while the J-RGCs are the most sensitive cells to NMDA excitotoxicity. These results strongly suggest that the differences in the genetic background of RGC types might provide valuable insights for understanding the selective susceptibility of RGCs to pathological insults and the development of a strategy to protect RGCs from death in disease conditions. In addition, our results show that RGCs lose dendrites before death and the sequence of the morphological and molecular events during RGC death suggests that the initial insult of NMDA excitotoxicity might set off a cascade of events independent of the primary insults. However, the kinetics of dendritic retraction in RGCs does not directly correlate to the susceptibility of type-specific RGC death.
Collapse
Affiliation(s)
- Ian Christensen
- Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Bo Lu
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States.,Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Ning Yang
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States.,Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Kevin Huang
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States.,Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Ping Wang
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States.,Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Ning Tian
- VA Salt Lake City Health Care System, Salt Lake City, UT, United States.,Department of Ophthalmology & Visual Sciences, University of Utah School of Medicine, Salt Lake City, UT, United States
| |
Collapse
|
19
|
Sano H, Namekata K, Kimura A, Shitara H, Guo X, Harada C, Mitamura Y, Harada T. Differential effects of N-acetylcysteine on retinal degeneration in two mouse models of normal tension glaucoma. Cell Death Dis 2019; 10:75. [PMID: 30692515 PMCID: PMC6349904 DOI: 10.1038/s41419-019-1365-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 12/17/2018] [Accepted: 01/14/2019] [Indexed: 12/24/2022]
Abstract
N-acetylcysteine (NAC) is widely used as a mucolytic agent and as an antidote to paracetamol overdose. NAC serves as a precursor of cysteine and stimulates the synthesis of glutathione in neural cells. Suppressing oxidative stress in the retina may be an effective therapeutic strategy for glaucoma, a chronic neurodegenerative disease of the retinal ganglion cells (RGCs) and optic nerves. Here we examined the therapeutic potential of NAC in two mouse models of normal tension glaucoma, in which excitatory amino-acid carrier 1 (EAAC1) or glutamate/aspartate transporter (GLAST) gene was deleted. EAAC1 is expressed in retinal neurons including RGCs, whereas GLAST is mainly expressed in Müller glial cells. Intraperitoneal administration of NAC prevented RGC degeneration and visual impairment in EAAC1-deficient (knockout; KO) mice, but not in GLAST KO mice. In EAAC1 KO mice, oxidative stress and autophagy were suppressed with increased glutathione levels by NAC treatment. Our findings suggest a possibility that systemic administration of NAC may be available for some types of glaucoma patients.
Collapse
Affiliation(s)
- Hiroki Sano
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.,Department of Ophthalmology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Hiroshi Shitara
- Laboratory for Transgenic Technology, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yoshinori Mitamura
- Department of Ophthalmology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.,Department of Ophthalmology, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| |
Collapse
|
20
|
Activation of 5-HT1A Receptors Promotes Retinal Ganglion Cell Function by Inhibiting the cAMP-PKA Pathway to Modulate Presynaptic GABA Release in Chronic Glaucoma. J Neurosci 2018; 39:1484-1504. [PMID: 30541912 DOI: 10.1523/jneurosci.1685-18.2018] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 12/12/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) receptor agonists are neuroprotective in CNS injury models. However, the neuroprotective functional implications and synaptic mechanism of 8-hydroxy-2- (di-n-propylamino) tetralin (8-OH-DPAT), a serotonin receptor (5-HT1A) agonist, in an adult male Wistar rat model of chronic glaucoma model remain unknown. We found that ocular hypertension decreased 5-HT1A receptor expression in rat retinas because the number of retinal ganglion cells (RGCs) was significantly reduced in rats with induced ocular hypertension relative to that in control retinas and 8-OH-DPAT enhanced the RGC viability. The protective effects of 8-OH-DPAT were blocked by intravitreal administration of the selective 5-HT1A antagonist WAY-100635 or the selective GABAA receptor antagonist SR95531. Using patch-clamp techniques, spontaneous and miniature GABAergic IPSCs (sIPSCs and mIPSCs, respectively) of RGCs in rat retinal slices were recorded. 8-OH-DPAT significantly increased the frequency and amplitude of GABAergic sIPSCs and mIPSCs in ON- and OFF-type RGCs. Among the signaling cascades mediated by the 5-HT1A receptor, the role of cAMP-protein kinase A (PKA) signaling was investigated. The 8-OH-DPAT-induced changes at the synaptic level were enhanced by PKA inhibition by H-89 and blocked by PKA activation with bucladesine. Furthermore, the density of phosphorylated PKA (p-PKA)/PKA was significantly increased in glaucomatous retinas and 8-OH-DPAT significantly decreased p-PKA/PKA expression, which led to the inhibition of PKA phosphorylation upon relieving neurotransmitter GABA release. These results showed that the activation of 5-HT1A receptors in retinas facilitated presynaptic GABA release functions by suppressing cAMP-PKA signaling and decreasing PKA phosphorylation, which could lead to the de-excitation of RGC circuits and suppress excitotoxic processes in glaucoma.SIGNIFICANCE STATEMENT We found that serotonin (5-HT) receptors in the retina (5-HT1A receptors) were downregulated after intraocular pressure elevation. Patch-clamp recordings demonstrated differences in the frequencies of miniature GABAergic IPSCs (mIPSCs) in ON- and OFF-type retinal ganglion cells (RGCs) and RGCs in normal and glaucomatous retinal slices. Therefore, phosphorylated protein kinase A (PKA) inhibition upon release of the neurotransmitter GABA was eliminated by 8-hydroxy-2- (di-n-propylamino) tetralin (8-OH-DPAT), which led to increased levels of GABAergic mIPSCs in ON- and OFF-type RGCs, thus enhancing RGC viability and function. These protective effects were blocked by the GABAA receptor antagonist SR95531 or the 5-HT1A antagonist WAY-100635. This study identified a novel mechanism by which activation of 5-HT1A receptors protects damaged RGCs via the cAMP-PKA signaling pathway that modulates GABAergic presynaptic activity.
Collapse
|
21
|
Harada C, Kimura A, Guo X, Namekata K, Harada T. Recent advances in genetically modified animal models of glaucoma and their roles in drug repositioning. Br J Ophthalmol 2018; 103:161-166. [PMID: 30366949 PMCID: PMC6362806 DOI: 10.1136/bjophthalmol-2018-312724] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/21/2018] [Accepted: 08/25/2018] [Indexed: 12/18/2022]
Abstract
Glaucoma is one of the leading causes of vision loss in the world. Currently, pharmacological intervention for glaucoma therapy is limited to eye drops that reduce intraocular pressure (IOP). Recent studies have shown that various factors as well as IOP are involved in the pathogenesis of glaucoma, especially in the subtype of normal tension glaucoma. To date, various animal models of glaucoma have been established, including glutamate/aspartate transporter knockout (KO) mice, excitatory amino acid carrier 1 KO mice, optineurin E50K knock-in mice, DBA/2J mice and experimentally induced models. These animal models are very useful for elucidating the pathogenesis of glaucoma and for identifying potential therapeutic targets. However, each model represents only some aspects of glaucoma, never the whole disease. This review will summarise the benefits and limitations of using disease models of glaucoma and recent basic research in retinal protection using existing drugs.
Collapse
Affiliation(s)
- Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| |
Collapse
|
22
|
Role of neuritin in retinal ganglion cell death in adult mice following optic nerve injury. Sci Rep 2018; 8:10132. [PMID: 29973613 PMCID: PMC6031618 DOI: 10.1038/s41598-018-28425-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 06/21/2018] [Indexed: 12/31/2022] Open
Abstract
Neuritin is a small extracellular protein that plays important roles in the process of neural development, synaptic plasticity, and neural cell survival. Here we investigated the function of neuritin in a mouse model of optic nerve injury (ONI). ONI induced upregulation of neuritin mRNA in the retina of WT mice. The retinal structure and the number of retinal ganglion cells (RGCs) were normal in adult neuritin knockout (KO) mice. In vivo retinal imaging and histopathological analyses demonstrated that RGC death and inner retinal degeneration following ONI were more severe in neuritin KO mice. Immunoblot analyses revealed that ONI-induced phosphorylation of Akt and ERK were suppressed in neuritin KO mice. Our findings suggest that neuritin has neuroprotective effects following ONI and may be useful for treatment of posttraumatic complication.
Collapse
|
23
|
Schur RM, Gao S, Yu G, Chen Y, Maeda A, Palczewski K, Lu ZR. New GABA modulators protect photoreceptor cells from light-induced degeneration in mouse models. FASEB J 2018; 32:3289-3300. [PMID: 29401616 DOI: 10.1096/fj.201701250r] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
No clinically approved therapies are currently available that prevent the onset of photoreceptor death in retinal degeneration. Signaling between retinal neurons is regulated by the release and uptake of neurotransmitters, wherein GABA is the main inhibitory neurotransmitter. In this work, novel 3-chloropropiophenone derivatives and the clinical anticonvulsants tiagabine and vigabatrin were tested to modulate GABA signaling and protect against light-induced retinal degeneration. Abca4-/-Rdh8-/- mice, an accelerated model of retinal degeneration, were exposed to intense light after prophylactic injections of one of these compounds. Imaging and functional assessments of the retina indicated that these compounds successfully protected photoreceptor cells from degeneration to maintain a full-visual-field response. Furthermore, these compounds demonstrated a strong safety profile in wild-type mice and did not compromise visual function or damage the retina, despite repeated administration. These results indicate that modulating inhibitory GABA signaling can offer prophylactic protection against light-induced retinal degeneration.-Schur, R. M., Gao, S., Yu, G., Chen, Y., Maeda, A., Palczewski, K., Lu, Z.-R. New GABA modulators protect photoreceptor cells from light-induced degeneration in mouse models.
Collapse
Affiliation(s)
- Rebecca M Schur
- Case Center for Biomolecular Engineering, Department of Biomedical Engineering, School of Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Songqi Gao
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Guanping Yu
- Case Center for Biomolecular Engineering, Department of Biomedical Engineering, School of Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yu Chen
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Akiko Maeda
- Department of Ophthalmology and Visual Sciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Krzysztof Palczewski
- Department of Pharmacology, Cleveland Center for Membrane and Structural Biology, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Zheng-Rong Lu
- Case Center for Biomolecular Engineering, Department of Biomedical Engineering, School of Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| |
Collapse
|
24
|
Sharif NA. iDrugs and iDevices Discovery Research: Preclinical Assays, Techniques, and Animal Model Studies for Ocular Hypotensives and Neuroprotectants. J Ocul Pharmacol Ther 2018; 34:7-39. [PMID: 29323613 DOI: 10.1089/jop.2017.0125] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Discovery ophthalmic research is centered around delineating the molecular and cellular basis of ocular diseases and finding and exploiting molecular and genetic pathways associated with them. From such studies it is possible to determine suitable intervention points to address the disease process and hopefully to discover therapeutics to treat them. An investigational new drug (IND) filing for a new small-molecule drug, peptide, antibody, genetic treatment, or a device with global health authorities requires a number of preclinical studies to provide necessary safety and efficacy data. Specific regulatory elements needed for such IND-enabling studies are beyond the scope of this article. However, to enhance the overall data packages for such entities and permit high-quality foundation-building publications for medical affairs, additional research and development studies are always desirable. This review aims to provide examples of some target localization/verification, ocular drug discovery processes, and mechanistic and portfolio-enhancing exploratory investigations for candidate drugs and devices for the treatment of ocular hypertension and glaucomatous optic neuropathy (neurodegeneration of retinal ganglion cells and their axons). Examples of compound screening assays, use of various technologies and techniques, deployment of animal models, and data obtained from such studies are also presented.
Collapse
Affiliation(s)
- Najam A Sharif
- 1 Global Alliances & External Research , Santen Incorporated, Emeryville, California.,2 Department of Pharmaceutical Sciences, Texas Southern University , Houston, Texas.,3 Department of Pharmacology and Neuroscience, University of North Texas Health Sciences Center , Fort Worth, Texas
| |
Collapse
|
25
|
Daly C, Ward R, Reynolds AL, Galvin O, Collery RF, Kennedy BN. Brain-Derived Neurotrophic Factor as a Treatment Option for Retinal Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:465-471. [PMID: 29721977 DOI: 10.1007/978-3-319-75402-4_57] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
This review discusses the therapeutic potential of brain-derived neurotrophic factor (BDNF) for retinal degeneration. BDNF, nerve growth factor (NGF), neurotrophin 3 (NT-3) and NT-4/NT-5 belong to the neurotrophin family. These neuronal modulators activate a common receptor and a specific tropomyosin-related kinase (Trk) receptor. BDNF was identified as a photoreceptor protectant in models of retinal degeneration as early as 1992. However, development of effective therapeutics that exploit this pathway has been difficult due to challenges in sustaining therapeutic levels in the retina.
Collapse
Affiliation(s)
- Conor Daly
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Ireland
| | - Rebecca Ward
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Ireland
| | - Alison L Reynolds
- School of Veterinary Medicine, University College Dublin, Belfield, Ireland
| | - Orla Galvin
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Ireland.,RenaSci Limited, BioCity, Nottingham, UK
| | - Ross F Collery
- Department of Ophthalmology and Visual Sciences, Eye Institute, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Breandán N Kennedy
- School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Ireland.
| |
Collapse
|
26
|
Bucolo C, Platania CBM, Drago F, Bonfiglio V, Reibaldi M, Avitabile T, Uva M. Novel Therapeutics in Glaucoma Management. Curr Neuropharmacol 2018; 16:978-992. [PMID: 28925883 PMCID: PMC6120119 DOI: 10.2174/1570159x15666170915142727] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 06/26/2017] [Accepted: 09/03/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Glaucoma is a progressive optic neuropathy characterized by retinal ganglion cell death and alterations of visual field. Elevated intraocular pressure (IOP) is considered the main risk factor of glaucoma, even though other factors cannot be ruled out, such as epigenetic mechanisms. OBJECTIVE An overview of the ultimate promising experimental drugs to manage glaucoma has been provided. RESULTS In particular, we have focused on purinergic ligands, KATP channel activators, gases (nitric oxide, carbon monoxide and hydrogen sulfide), non-glucocorticoid steroidal compounds, neurotrophic factors, PI3K/Akt activators, citicoline, histone deacetylase inhibitors, cannabinoids, dopamine and serotonin receptors ligands, small interference RNA, and Rho kinase inhibitors. CONCLUSIONS The review has been also endowed of a brief chapter on last reports about potential neuroprotective benefits of anti-glaucoma drugs already present in the market.
Collapse
Affiliation(s)
- Claudio Bucolo
- Address correspondence to this author at the Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Via S. Sofia 97, 95123 Catania, Italy; Tel: +39 095 4781196;
| | | | | | | | | | | | | |
Collapse
|
27
|
Son MS, Park CH, Kim JW. Effect of Valproic Acid on Nitric Oxide and Nitric Oxide Synthase in Trabecular Meshwork Cell. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2018. [DOI: 10.3341/jkos.2018.59.6.543] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Myung Seo Son
- Department of Ophthalmology, Catholic University of Daegu School of Medicine, Daegu, Korea
| | | | - Jae Woo Kim
- Department of Ophthalmology, Catholic University of Daegu School of Medicine, Daegu, Korea
| |
Collapse
|
28
|
Effects of neuroactive agents on axonal growth and pathfinding of retinal ganglion cells generated from human stem cells. Sci Rep 2017; 7:16757. [PMID: 29196712 PMCID: PMC5711798 DOI: 10.1038/s41598-017-16727-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/16/2017] [Indexed: 12/22/2022] Open
Abstract
We recently established a novel method for generating functional human retinal ganglion cells (RGCs) from human induced pluripotent cells (hiPSCs). Here, we confirmed that RGCs can also be generated from human embryonic stem cells (hESCs). We investigated the usefulness of human RGCs with long axons for assessing the effects of chemical agents, such as the neurotrophic factor, nerve growth factor (NGF), and the chemorepellent factors, semaphorin 3 A (SEMA3A) and SLIT1. The effects of direct and local administration of each agent on axonal projection were evaluated by immunohistochemistry, real-time polymerase chain reaction (PCR), and real-time imaging, in which the filopodia of the growth cone served as an excellent marker. A locally sustained agent system showed that the axons elongate towards NGF, but were repelled by SEMA3A and SLIT1. Focally transplanted beads that released SLIT1 bent the pathfinding of axons, imitating normal retinal development. Our innovative system for assessing the effects of chemical compounds using human RGCs may facilitate development of novel drugs for the examination, prophylaxis, and treatment of diseases. It may also be useful for observing the physiology of the optic nerve in vitro, which might lead to significant progress in the science of human RGCs.
Collapse
|
29
|
A Brain-Derived Neurotrophic Factor Mimetic Is Sufficient to Restore Cone Photoreceptor Visual Function in an Inherited Blindness Model. Sci Rep 2017; 7:11320. [PMID: 28900183 PMCID: PMC5595969 DOI: 10.1038/s41598-017-11513-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 08/25/2017] [Indexed: 01/25/2023] Open
Abstract
Controversially, histone deacetylase inhibitors (HDACi) are in clinical trial for the treatment of inherited retinal degeneration. Utilizing the zebrafish dyeucd6 model, we determined if treatment with HDACi can rescue cone photoreceptor-mediated visual function. dye exhibit defective visual behaviour and retinal morphology including ciliary marginal zone (CMZ) cell death and decreased photoreceptor outer segment (OS) length, as well as gross morphological defects including hypopigmentation and pericardial oedema. HDACi treatment of dye results in significantly improved optokinetic (OKR) (~43 fold, p < 0.001) and visualmotor (VMR) (~3 fold, p < 0.05) responses. HDACi treatment rescued gross morphological defects and reduced CMZ cell death by 80%. Proteomic analysis of dye eye extracts suggested BDNF-TrkB and Akt signaling as mediators of HDACi rescue in our dataset. Co-treatment with the TrkB antagonist ANA-12 blocked HDACi rescue of visual function and associated Akt phosphorylation. Notably, sole treatment with a BDNF mimetic, 7,8-dihydroxyflavone hydrate, significantly rescued dye visual function (~58 fold increase in OKR, p < 0.001, ~3 fold increase in VMR, p < 0.05). In summary, HDACi and a BDNF mimetic are sufficient to rescue retinal cell death and visual function in a vertebrate model of inherited blindness.
Collapse
|
30
|
Akaiwa K, Namekata K, Azuchi Y, Guo X, Kimura A, Harada C, Mitamura Y, Harada T. Edaravone suppresses retinal ganglion cell death in a mouse model of normal tension glaucoma. Cell Death Dis 2017; 8:e2934. [PMID: 28703795 PMCID: PMC5550882 DOI: 10.1038/cddis.2017.341] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 06/06/2017] [Accepted: 06/19/2017] [Indexed: 01/16/2023]
Abstract
Glaucoma, one of the leading causes of irreversible blindness, is characterized by progressive degeneration of optic nerves and retinal ganglion cells (RGCs). In the mammalian retina, excitatory amino-acid carrier 1 (EAAC1) is expressed in neural cells, including RGCs. Loss of EAAC1 leads to RGC degeneration without elevated intraocular pressure (IOP) and exhibits glaucomatous pathology including glutamate neurotoxicity and oxidative stress. In the present study, we found that edaravone, a free radical scavenger that is used for treatment of acute brain infarction and amyotrophic lateral sclerosis (ALS), reduces oxidative stress and prevents RGC death and thinning of the inner retinal layer in EAAC1-deficient (KO) mice. In addition, in vivo electrophysiological analyses demonstrated that visual impairment in EAAC1 KO mice was ameliorated with edaravone treatment, clearly establishing that edaravone beneficially affects both histological and functional aspects of the glaucomatous retina. Our findings raise intriguing possibilities for the management of glaucoma by utilizing a widely prescribed drug for the treatment of acute brain infarction and ALS, edaravone, in combination with conventional treatments to lower IOP.
Collapse
Affiliation(s)
- Kei Akaiwa
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.,Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yuriko Azuchi
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yoshinori Mitamura
- Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.,Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
| |
Collapse
|
31
|
Targeting Oxidative Stress for Treatment of Glaucoma and Optic Neuritis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:2817252. [PMID: 28270908 PMCID: PMC5320364 DOI: 10.1155/2017/2817252] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 01/09/2017] [Indexed: 12/31/2022]
Abstract
Glaucoma is a neurodegenerative disease of the eye and it is one of the leading causes of blindness. Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons, namely, the optic nerve, usually associated with elevated intraocular pressure (IOP). Current glaucoma therapies target reduction of IOP, but since RGC death is the cause of irreversible vision loss, neuroprotection may be an effective strategy for glaucoma treatment. One of the risk factors for glaucoma is increased oxidative stress, and drugs with antioxidative properties including valproic acid and spermidine, as well as inhibition of apoptosis signal-regulating kinase 1, an enzyme that is involved in oxidative stress, have been reported to prevent glaucomatous retinal degeneration in mouse models of glaucoma. Optic neuritis is a demyelinating inflammation of the optic nerve that presents with visual impairment and it is commonly associated with multiple sclerosis, a chronic demyelinating disease of the central nervous system. Although steroids are commonly used for treatment of optic neuritis, reduction of oxidative stress by approaches such as gene therapy is effective in ameliorating optic nerve demyelination in preclinical studies. In this review, we discuss oxidative stress as a therapeutic target for glaucoma and optic neuritis.
Collapse
|
32
|
Valproic acid and ASK1 deficiency ameliorate optic neuritis and neurodegeneration in an animal model of multiple sclerosis. Neurosci Lett 2016; 639:82-87. [PMID: 28040492 DOI: 10.1016/j.neulet.2016.12.057] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/21/2016] [Accepted: 12/23/2016] [Indexed: 11/23/2022]
Abstract
Optic neuritis, which is an acute inflammatory demyelinating syndrome of the central nervous system, is one of the major complications in multiple sclerosis (MS). Herein, we investigated the therapeutic potential of valproic acid (VPA) on optic neuritis in experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. EAE was induced in C57BL/6 mice by immunization with MOG35-55 and VPA (300mg/kg) was administered via intraperitoneal injection once daily from day 3 postimmunization until the end of the experimental period (day 28). VPA treatment suppressed neuroinflammation and decreased the clinical score of EAE at an early phase (from day 12-14 after immunization). We also examined the effects of apoptosis signal-regulating kinase 1 (ASK1), an evolutionarily conserved signaling intermediate for innate immunity, in EAE mice. ASK1 deficiency strongly suppressed microglial activation and decreased the clinical score of EAE at a late phase (day 25, 27 and 28 after immunization). When VPA was administered to ASK1-deficient EAE mice, the clinical score was suppressed in both early and late phases (from day 12-28 after immunization) and showed synergistic effects on protection of retinal neurons. Our findings raise intriguing possibilities that the widely prescribed drug VPA and ASK1 inhibition may be useful for neuroinflammatory disorders including optic neuritis and MS.
Collapse
|
33
|
Guo X, Kimura A, Azuchi Y, Akiyama G, Noro T, Harada C, Namekata K, Harada T. Caloric restriction promotes cell survival in a mouse model of normal tension glaucoma. Sci Rep 2016; 6:33950. [PMID: 27669894 PMCID: PMC5037377 DOI: 10.1038/srep33950] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/06/2016] [Indexed: 12/15/2022] Open
Abstract
Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons. We previously reported that loss of glutamate transporters (EAAC1 or GLAST) in mice leads to RGC degeneration that is similar to normal tension glaucoma and these animal models are useful in examining potential therapeutic strategies. Caloric restriction has been reported to increase longevity and has potential benefits in injury and disease. Here we investigated the effects of every-other-day fasting (EODF), a form of caloric restriction, on glaucomatous pathology in EAAC1−/− mice. EODF suppressed RGC death and retinal degeneration without altering intraocular pressure. Moreover, visual impairment was ameliorated with EODF, indicating the functional significance of the neuroprotective effect of EODF. Several mechanisms associated with this neuroprotection were explored. We found that EODF upregulated blood β-hydroxybutyrate levels and increased histone acetylation in the retina. Furthermore, it elevated retinal mRNA expression levels of neurotrophic factors and catalase, whereas it decreased oxidative stress levels in the retina. Our findings suggest that EODF, a safe, non-invasive, and low-cost treatment, may be available for glaucoma therapy.
Collapse
Affiliation(s)
- Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yuriko Azuchi
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Goichi Akiyama
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takahiko Noro
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| |
Collapse
|
34
|
Kimura A, Namekata K, Guo X, Harada C, Harada T. Neuroprotection, Growth Factors and BDNF-TrkB Signalling in Retinal Degeneration. Int J Mol Sci 2016; 17:ijms17091584. [PMID: 27657046 PMCID: PMC5037849 DOI: 10.3390/ijms17091584] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/01/2016] [Accepted: 09/14/2016] [Indexed: 12/18/2022] Open
Abstract
Neurotrophic factors play key roles in the development and survival of neurons. The potent neuroprotective effects of neurotrophic factors, including brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), glial cell-line derived neurotrophic factor (GDNF) and nerve growth factor (NGF), suggest that they are good therapeutic candidates for neurodegenerative diseases. Glaucoma is a neurodegenerative disease of the eye that causes irreversible blindness. It is characterized by damage to the optic nerve, usually due to high intraocular pressure (IOP), and progressive degeneration of retinal neurons called retinal ganglion cells (RGCs). Current therapy for glaucoma focuses on reduction of IOP, but neuroprotection may also be beneficial. BDNF is a powerful neuroprotective agent especially for RGCs. Exogenous application of BDNF to the retina and increased BDNF expression in retinal neurons using viral vector systems are both effective in protecting RGCs from damage. Furthermore, induction of BDNF expression by agents such as valproic acid has also been beneficial in promoting RGC survival. In this review, we discuss the therapeutic potential of neurotrophic factors in retinal diseases and focus on the differential roles of glial and neuronal TrkB in neuroprotection. We also discuss the role of neurotrophic factors in neuroregeneration.
Collapse
Affiliation(s)
- Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| | - Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan.
| |
Collapse
|
35
|
Nucci C, Russo R, Martucci A, Giannini C, Garaci F, Floris R, Bagetta G, Morrone LA. New strategies for neuroprotection in glaucoma, a disease that affects the central nervous system. Eur J Pharmacol 2016; 787:119-26. [DOI: 10.1016/j.ejphar.2016.04.030] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/23/2016] [Accepted: 04/14/2016] [Indexed: 01/30/2023]
|
36
|
Geeraerts E, Dekeyster E, Gaublomme D, Salinas-Navarro M, De Groef L, Moons L. A freely available semi-automated method for quantifying retinal ganglion cells in entire retinal flatmounts. Exp Eye Res 2016; 147:105-113. [PMID: 27107795 DOI: 10.1016/j.exer.2016.04.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 04/08/2016] [Accepted: 04/18/2016] [Indexed: 01/13/2023]
Abstract
Glaucomatous optic neuropathies are characterized by progressive loss of retinal ganglion cells (RGCs), the neurons that connect the eye to the brain. Quantification of these RGCs is a cornerstone in experimental optic neuropathy research and commonly performed via manually quantifying parts of the retina. However, this is a time-consuming process subject to inter- and intra-observer variability. Here we present a freely available ImageJ script to semi-automatically quantify RGCs in entire retinal flatmounts after immunostaining for the RGC-specific transcription factor Brn3a. The blob-like signal of Brn3a-immunopositive RGCs is enhanced via eigenvalues of the Hessian matrix and the resulting local maxima are counted as RGCs. After the user has outlined the retinal flatmount area, the total RGC number and retinal area are reported and an isodensity map, showing the RGC density distribution across the retina, is created. The semi-automated quantification shows a very strong correlation (Pearson's r ≥ 0.99) with manual counts for both widefield and confocal images, thereby validating the data generated via the developed script. Moreover, application of this method in established glaucomatous optic neuropathy models such as N-methyl-D-aspartate-induced excitotoxicity, optic nerve crush and laser-induced ocular hypertension revealed RGC loss conform with literature. Compared to manual counting, the described automated quantification method is faster and shows user-independent consistency. Furthermore, as the script detects the RGC number in entire retinal flatmounts, the method allows detection of regional differences in RGC density. As such, it can help advance research investigating the degenerative mechanisms of glaucomatous optic neuropathies and the effectiveness of new neuroprotective treatments. Because the script is flexible and easy to optimize due to a low number of critical parameters, it can potentially be applied in combination with other tissues or alternative labeling protocols.
Collapse
Affiliation(s)
- E Geeraerts
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| | - E Dekeyster
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| | - D Gaublomme
- Unit for Molecular Immunology and Inflammation, VIB Inflammation Research Centre, Ghent University, Ghent, Belgium; Laboratory for Molecular Immunology and Inflammation, Department of Rheumatology, Ghent University Hospital, Ghent, Belgium
| | - M Salinas-Navarro
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| | - L De Groef
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium
| | - L Moons
- Laboratory of Neural Circuit Development and Regeneration, Animal Physiology and Neurobiology Section, Department of Biology, KU Leuven, Leuven, Belgium.
| |
Collapse
|
37
|
Harada C, Azuchi Y, Noro T, Guo X, Kimura A, Namekata K, Harada T. TrkB Signaling in Retinal Glia Stimulates Neuroprotection after Optic Nerve Injury. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:3238-47. [PMID: 26476348 DOI: 10.1016/j.ajpath.2015.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/13/2015] [Accepted: 08/20/2015] [Indexed: 12/13/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) regulates neural cell survival mainly by activating TrkB receptors. Several lines of evidence support a key role for BDNF-TrkB signaling in survival of adult retinal ganglion cells in animal models of optic nerve injury (ONI), but the neuroprotective effect of exogenous BDNF is transient. Glial cells have recently attracted considerable attention as mediators of neural cell survival, and TrkB expression in retinal glia suggests its role in neuroprotection. To elucidate this point directly, we examined the effect of ONI on TrkB(flox/flox):glial fibrillary acidic protein (GFAP)-Cre+ (TrkB(GFAP)) knockout (KO) mice, in which TrkB is deleted in retinal glial cells. ONI markedly increased mRNA expression levels of basic fibroblast growth factor (bFGF) in wild-type (WT) mice but not in TrkB(GFAP) KO mice. Immunohistochemical analysis at 7 days after ONI (d7) revealed bFGF up-regulation mainly occurred in Müller glia. ONI-induced retinal ganglion cell loss in WT mice was consistently mild compared with TrkB(GFAP) KO mice at d7. On the other hand, ONI severely decreased TrkB expression in both WT and TrkB(GFAP) KO mice after d7, and the severity of retinal degeneration was comparable with TrkB(GFAP) KO mice at d14. Our data provide direct evidence that glial TrkB signaling plays an important role in the early stage of neural protection after traumatic injury.
Collapse
Affiliation(s)
- Chikako Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yuriko Azuchi
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Takahiko Noro
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan; Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Xiaoli Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Atsuko Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Kazuhiko Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
| | - Takayuki Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| |
Collapse
|
38
|
Noro T, Namekata K, Kimura A, Guo X, Azuchi Y, Harada C, Nakano T, Tsuneoka H, Harada T. Spermidine promotes retinal ganglion cell survival and optic nerve regeneration in adult mice following optic nerve injury. Cell Death Dis 2015; 6:e1720. [PMID: 25880087 PMCID: PMC4650557 DOI: 10.1038/cddis.2015.93] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/13/2015] [Accepted: 03/02/2015] [Indexed: 12/19/2022]
Abstract
Spermidine acts as an endogenous free radical scavenger and inhibits the action of reactive oxygen species. In this study, we examined the effects of spermidine on retinal ganglion cell (RGC) death in a mouse model of optic nerve injury (ONI). Daily ingestion of spermidine reduced RGC death following ONI and sequential in vivo retinal imaging revealed that spermidine effectively prevented retinal degeneration. Apoptosis signal-regulating kinase-1 (ASK1) is an evolutionarily conserved mitogen-activated protein kinase kinase kinase and has an important role in ONI-induced RGC apoptosis. We demonstrated that spermidine suppresses ONI-induced activation of the ASK1-p38 mitogen-activated protein kinase pathway. Moreover, production of chemokines important for microglia recruitment was decreased with spermidine treatment and, consequently, accumulation of retinal microglia is reduced. In addition, the ONI-induced expression of inducible nitric oxide synthase in the retina was inhibited with spermidine treatment, particularly in microglia. Furthermore, daily spermidine intake enhanced optic nerve regeneration in vivo. Our findings indicate that spermidine stimulates neuroprotection as well as neuroregeneration, and may be useful for treatment of various neurodegenerative diseases including glaucoma.
Collapse
Affiliation(s)
- T Noro
- 1] Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan [2] Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - K Namekata
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - A Kimura
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - X Guo
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Y Azuchi
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - C Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - T Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - H Tsuneoka
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - T Harada
- Visual Research Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| |
Collapse
|
39
|
Kimura A, Guo X, Noro T, Harada C, Tanaka K, Namekata K, Harada T. Valproic acid prevents retinal degeneration in a murine model of normal tension glaucoma. Neurosci Lett 2015; 588:108-13. [DOI: 10.1016/j.neulet.2014.12.054] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Revised: 12/22/2014] [Accepted: 12/25/2014] [Indexed: 12/28/2022]
|