1
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Jiang R, Lv Y, Chen B, Wu X, Zou Y, Liang L. Antioxidant effect of gallic acid on retinal ganglion cells in glaucoma model. Sci Rep 2024; 14:14907. [PMID: 38942959 PMCID: PMC11213916 DOI: 10.1038/s41598-024-65965-7] [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: 12/21/2023] [Accepted: 06/25/2024] [Indexed: 06/30/2024] Open
Abstract
To evaluate the protective effect of gallic acid on the optic nerve by studying the inhibitory effect of gallic acid on oxidative stress in retinal ganglion cells. 100 male SD rats were randomly divided into four groups: normal control group, simple high IOP group, 0.5% gallic acid experimental group, and 1% gallic acid experimental group. HE staining, immunofluorescence, DHE staining, Western blot, and q-PCR were used to observe the antioxidant effect of gallic acid on the retina of acute ocular hypertension rats. HE staining of the retina of SD rats confirmed that the nucleus of RGCs was clear, the thickness of the RNFL was regular in the normal control group, and the nucleus of RGCs was ruptured and lysed in the simple high intraocular pressure (IOP) group and the gallic acid group, and the thickness of the RNFL was significantly thickened, but the thickness of the RNFL in the gallic acid group was significantly reduced compared with that in the simple high IOP group (p < 0.05). DHE staining showed that ROS content in the simple high IOP group was significantly increased compared with the normal control group, and ROS content was significantly decreased after the application of gallic acid (p < 0.05). Immunofluorescence staining with Brn-3a antibody confirmed that the number of RGCs was significantly reduced in the simple high IOP group compared with the normal control group, whereas after application of gallic acid, the number of RGCs was significantly more in the gallic acid group than in the simple high IOP group (p < 0.05). Western Blot and q-PCR confirmed that hypoxia-inducing factor 1α (HIF-1α) protein content and transcription level were significantly increased in the retinal tissue of the simple high IOP group, and gallic acid could inhibit HIF-1α protein content (p < 0.05) and reduce transcription factor level (p < 0.05). Gallic acid exerts a protective effect on RGC by inhibiting oxidative stress in rats with acute IOP elevation.
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Affiliation(s)
- Ruping Jiang
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China
| | - Yao Lv
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China
| | - Binlin Chen
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China
| | - Xia Wu
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China
| | - Yuan Zou
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China
| | - Liang Liang
- Department of Ophthalmology, Yichang Central People's Hospital, The First College of Clinical Medical Science, China Three Gorges University, Yichang, 443003, China.
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2
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Lv J, Gao R, Wang Y, Huang C, Wu R. Protective effect of leukemia inhibitory factor on the retinal injury induced by acute ocular hypertension in rats. Exp Ther Med 2022; 25:19. [PMID: 36561619 PMCID: PMC9748713 DOI: 10.3892/etm.2022.11717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 10/04/2022] [Indexed: 11/23/2022] Open
Abstract
Glaucoma is one of the leading causes of irreversible blindness worldwide. As such, neuroprotective therapy is essential for the treatment of this disease. Leukemia inhibitory factor (LIF) is a member of the IL-6 cytokine family and the LIF signaling pathway is considered to be one of the major endogenous factors mediating neuroprotection in the retina. Therefore, the present study aimed to investigate the possible effects of LIF in acute ocular hypertension (AOH). The intraocular pressure in rat eyes was raised to 110 mmHg for 1 h by infusing the anterior chamber with normal saline to establish the AOH model. In the treatment group, LIF was then injected into the vitreous cavity after AOH was ceased. The retinal tissues were obtained after the termination of AOH, and H&E staining was conducted to assess the morphological damage. The number of retinal ganglion cells (RGCs) was counted using the Fluoro-Gold retrograde staining method. TUNEL staining was used to determine the extent of apoptosis among the retinal cells. In addition, the protein expression levels of cleaved caspase-3, poly (ADP-ribose) polymerase (PARP), STAT3 and components of the AKT/mTOR/70-kDa ribosomal protein S6 kinase (p70S6K) signaling pathway were examined by western blotting. The results showed that AOH induced tissue swelling and structural damage in the retina, which were reversed by LIF injection. In the LIF treatment group, RGC loss was significantly inhibited and the quantity of TUNEL-stained cells was also significantly reduced, whereas the expression of cleaved caspase-3 and PARP was decreased. Furthermore, increased phosphorylation of STAT3, AKT, mTOR and p70S6K was observed after LIF treatment. By contrast, pretreatment with the STAT3 inhibitor C188-9 or the PI3K/AKT/mTOR inhibitor LY3023414 reversed the LIF-induced inhibition of RGC loss. These results suggested that exogenous LIF treatment inhibited the retinal damage induced by AOH, which was associated with the activation of STAT3 and mTOR/p70S6K signaling. Therefore, LIF may serve a role in neuroprotection for glaucoma treatment.
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Affiliation(s)
- Jiexuan Lv
- Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361001, P.R. China
| | - Ruxin Gao
- Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361001, P.R. China
| | - Yao Wang
- Shaanxi Provincial Key Laboratory of Ophthalmology, Shaanxi Institute of Ophthalmology, Shaanxi Clinical Study Center for Ocular Disease, The First Affiliated Hospital of Xi'an Jiaotong University, Medical School, Northwest University, Xi'an, Shaanxi 710002, P.R. China
| | - Changquan Huang
- Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361001, P.R. China,Fujian Provincial Key Laboratory of Corneal and Ocular Surface Diseases, Xiamen, Fujian 361001, P.R. China
| | - Renyi Wu
- Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361001, P.R. China,Fujian Provincial Key Laboratory of Corneal and Ocular Surface Diseases, Xiamen, Fujian 361001, P.R. China,Department of Glaucoma, Shanghai Peace Eye Hospital, Shanghai 200437, P.R. China,Correspondence to: Professor Renyi Wu, Eye Institute and Affiliated Xiamen Eye Center of Xiamen University, School of Medicine, Xiamen University, 336 Xiahe Road, Xiamen, Fujian 361001, P.R. China
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3
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Regeneration des Sehnerven – Wird das einmal Realität? Ophthalmologe 2022; 119:919-928. [DOI: 10.1007/s00347-022-01628-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2022] [Indexed: 10/18/2022]
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4
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Nicoară SD, Brie I, Jurj A, Sorițău O. The Future of Stem Cells and Their Derivates in the Treatment of Glaucoma. A Critical Point of View. Int J Mol Sci 2021; 22:ijms222011077. [PMID: 34681739 PMCID: PMC8540760 DOI: 10.3390/ijms222011077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/07/2021] [Accepted: 10/09/2021] [Indexed: 12/24/2022] Open
Abstract
This review focuses on the clinical translation of preclinical studies, especially those that have used stem cells in the treatment of glaucoma, with an emphasis on optic nerve regeneration. The studies referred to in the review aim to treat optic nerve atrophy, while cell therapies targeting other sites in the eye, such as the trabecular meshwork, have not been addressed. Such complex and varied pathophysiological mechanisms that lead to glaucoma may explain the fact that although stem cells have a high capacity of neuronal regeneration, the treatments performed did not have the expected results and the promise offered by animal studies was not achieved. By analyzing the facts associated with failure, important lessons are to be learned: the type of stem cells that are used, the route of administration, the selection of patients eligible for these treatments, additional therapies that support stem cells transplantation and their mode of action, methods of avoiding the host’s immune response. Many of these problems could be solved using exosomes (EV), but also miRNA, which allows more targeted approaches with minimal side effects.
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Affiliation(s)
- Simona Delia Nicoară
- Department of Ophthalmology, “Iuliu Hatieganu” University of Medicine and Pharmacy, 8 Victor Babeș Street, 400012 Cluj-Napoca, Romania
- Clinic of Ophthalmology, Emergency County Hospital, 3–5 Clinicilor Street, 40006 Cluj-Napoca, Romania
- Correspondence: or ; Tel.: +40-264592771
| | - Ioana Brie
- “Ion Chiricuță” Institute of Oncology, Laboratory of Cell Biology and Radiobiology, 34–36 Republicii Street, 400010 Cluj-Napoca, Romania; (I.B.); (O.S.)
| | - Ancuța Jurj
- Research Center for Functional Genomics, Biomedicine and Translational Medicine, “Iuliu Hațieganu” University of Medicine and Pharmacy, 8 Victor Babeș Street, 400012 Cluj-Napoca, Romania;
| | - Olga Sorițău
- “Ion Chiricuță” Institute of Oncology, Laboratory of Cell Biology and Radiobiology, 34–36 Republicii Street, 400010 Cluj-Napoca, Romania; (I.B.); (O.S.)
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Zhang J, Jiao J, Niu M, Gao X, Zhang G, Yu H, Yang X, Liu L. Ten Years of Knowledge of Nano-Carrier Based Drug Delivery Systems in Ophthalmology: Current Evidence, Challenges, and Future Prospective. Int J Nanomedicine 2021; 16:6497-6530. [PMID: 34588777 PMCID: PMC8473849 DOI: 10.2147/ijn.s329831] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 08/30/2021] [Indexed: 12/13/2022] Open
Abstract
The complex drug delivery barrier in the eye reduces the bioavailability of many drugs, resulting in poor therapeutic effects. It is necessary to investigate new drugs through appropriate delivery routes and vehicles. Nanotechnology has utilized various nano-carriers to develop potential ocular drug delivery techniques that interact with the ocular mucosa, prolong the retention time of drugs in the eye, and increase permeability. Additionally, nano-carriers such as liposomes, nanoparticles, nano-suspensions, nano-micelles, and nano-emulsions have grown in popularity as an effective theranostic application to combat different microbial superbugs. In this review, we summarize the nano-carrier based drug delivery system developments over the last decade, particularly review the biology, methodology, approaches, and clinical applications of nano-carrier based drug delivery system in the field of ocular therapeutics. Furthermore, this review addresses upcoming challenges, and provides an outlook on potential future trends of nano-carrier-based drug delivery approaches in ophthalmology, and hopes to eventually provide successful applications for treating ocular diseases.
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Affiliation(s)
- Jie Zhang
- Department of Ophthalmology, Weifang Eye Hospital, Weifang, 261041, People's Republic of China
| | - Jinghua Jiao
- Department of Anesthesiology, Central Hospital, Shenyang Medical College, Shenyang, 110024, People's Republic of China
| | - Meng Niu
- Department of Radiology, First Hospital of China Medical University, Shenyang, 110001, People's Republic of China
| | - Xiaotong Gao
- Department of Endocrinology and Metabolism and the Institute of Endocrinology, The First Hospital of China Medical University, Shenyang, 110001, People's Republic of China
| | - Guisen Zhang
- Department of Retina, Inner Mongolia Chaoju Eye Hospital, Hohhot, 010050, People's Republic of China
| | - Honghua Yu
- Guangdong Eye Institute, Department of Ophthalmology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences; School of Medicine, South China University of Technology, Guangzhou, 510120, People's Republic of China
| | - Xiaohong Yang
- Guangdong Eye Institute, Department of Ophthalmology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences; School of Medicine, South China University of Technology, Guangzhou, 510120, People's Republic of China
| | - Lei Liu
- Guangdong Eye Institute, Department of Ophthalmology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences; School of Medicine, South China University of Technology, Guangzhou, 510120, People's Republic of China.,Department of Ophthalmology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, People's Republic of China
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6
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Signal transducer and activator of transcription-3 mediated neuroprotective effect of interleukin-6 on cobalt chloride mimetic hypoxic cell death in R28 cells. Mol Biol Rep 2021; 48:6197-6203. [PMID: 34318437 DOI: 10.1007/s11033-021-06586-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/20/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Hypoxic injury to retinal ganglionic cells and adjoining glia is implicated in glaucomatous optic neuropathy. The present study evaluates the effect of IL-6 on R28 retinal precursor cell line exposed to hypoxic injury. METHODS AND RESULTS Apoptotic cell death induced by hypoxia mimetic CoCl2 in R28 cells with or without IL-6 treatment was measured using cell viability assays and apoptotic markers. Oxidative stress was also measured. Hypoxia induced by mimetic CoCl2 led to a time and concentration dependent apoptosis of cells mediated by disruption of mitochondrial membrane potential and activation of caspase 3. Cells pre-treated with IL-6 demonstrated significantly higher viability and mitochondrial integrity under hypoxic conditions. A critical role of STAT3 was observed in mediating the cytoprotective effects of IL-6. Treatment of cells with IL-6 led to STAT3-mediated expression of the Bcl-2 family proteins and MnSOD. CONCLUSIONS The data from the present study indicate cytoprotective role of IL-6 and suggest a previously unreported mechanism of neuroprotection via STAT3 mediated signaling.
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Sher I, Moverman D, Ketter-Katz H, Moisseiev E, Rotenstreich Y. In vivo retinal imaging in translational regenerative research. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1096. [PMID: 33145315 PMCID: PMC7575995 DOI: 10.21037/atm-20-4355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Regenerative translational studies must include a longitudinal assessment of the changes in retinal structure and function that occur as part of the natural history of the disease and those that result from the studied intervention. Traditionally, retinal structural changes have been evaluated by histological analysis which necessitates sacrificing the animals. In this review, we describe key imaging approaches such as fundus imaging, optical coherence tomography (OCT), OCT-angiography, adaptive optics (AO), and confocal scanning laser ophthalmoscopy (cSLO) that enable noninvasive, non-contact, and fast in vivo imaging of the posterior segment. These imaging technologies substantially reduce the number of animals needed and enable progression analysis and longitudinal follow-up in individual animals for accurate assessment of disease natural history, effects of interventions and acute changes. We also describe the benefits and limitations of each technology, as well as outline possible future directions that can be taken in translational retinal imaging studies.
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Affiliation(s)
- Ifat Sher
- Goldschleger Eye Institute, Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Moverman
- Goldschleger Eye Institute, Sheba Medical Center, Tel-Hashomer, Israel
| | - Hadas Ketter-Katz
- Goldschleger Eye Institute, Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Elad Moisseiev
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Department of Ophthalmology, Meir Medical Center, Kfar Saba, Israel
| | - Ygal Rotenstreich
- Goldschleger Eye Institute, Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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8
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Eastlake K, Wang W, Jayaram H, Murray‐Dunning C, Carr AJF, Ramsden CM, Vugler A, Gore K, Clemo N, Stewart M, Coffey P, Khaw PT, Limb GA. Phenotypic and Functional Characterization of Müller Glia Isolated from Induced Pluripotent Stem Cell-Derived Retinal Organoids: Improvement of Retinal Ganglion Cell Function upon Transplantation. Stem Cells Transl Med 2019; 8:775-784. [PMID: 31037833 PMCID: PMC6646702 DOI: 10.1002/sctm.18-0263] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/22/2019] [Indexed: 12/25/2022] Open
Abstract
Glaucoma is one of the leading causes of blindness, and there is an ongoing need for new therapies. Recent studies indicate that cell transplantation using Müller glia may be beneficial, but there is a need for novel sources of cells to provide therapeutic benefit. In this study, we have isolated Müller glia from retinal organoids formed by human induced pluripotent stem cells (hiPSCs) in vitro and have shown their ability to partially restore visual function in rats depleted of retinal ganglion cells by NMDA. Based on the present results, we suggest that Müller glia derived from retinal organoids formed by hiPSC may provide an attractive source of cells for human retinal therapies, to prevent and treat vision loss caused by retinal degenerative conditions. Stem Cells Translational Medicine 2019;8:775&784.
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Affiliation(s)
- Karen Eastlake
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Weixin Wang
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Hari Jayaram
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Celia Murray‐Dunning
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Amanda J. F. Carr
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Conor M. Ramsden
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Anthony Vugler
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | | | | | - Mark Stewart
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Pete Coffey
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - Peng T. Khaw
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
| | - G. Astrid Limb
- NIHR Biomedical Research CentreUCL Institute of Ophthalmology and Moorfields Eye HospitalLondonUnited Kingdom
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9
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Herrera E, Agudo-Barriuso M, Murcia-Belmonte V. Cranial Pair II: The Optic Nerves. Anat Rec (Hoboken) 2018; 302:428-445. [DOI: 10.1002/ar.23922] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 04/19/2017] [Accepted: 05/14/2017] [Indexed: 11/12/2022]
Affiliation(s)
- Eloísa Herrera
- Instituto de Neurociencias de Alicante (Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH); Av. Santiago Ramón y Cajal, s/n., 03550 Sant Joan d'Alacant Alicante Spain
| | - Marta Agudo-Barriuso
- Departamento de Oftalmología, Facultad de Medicina; Universidad de Murcia, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca (IMIB-Arrixaca); Murcia Spain
| | - Verónica Murcia-Belmonte
- Instituto de Neurociencias de Alicante (Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH); Av. Santiago Ramón y Cajal, s/n., 03550 Sant Joan d'Alacant Alicante Spain
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10
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Hilla AM, Fischer D. Studying the Role of Microglia in Neurodegeneration and Axonal Regeneration in the murine Visual System. Bio Protoc 2018; 8:e2979. [PMID: 34395779 DOI: 10.21769/bioprotoc.2979] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/02/2018] [Accepted: 08/05/2018] [Indexed: 11/02/2022] Open
Abstract
Microglia reside in the central nervous system (CNS) and are involved in the maintenance of the physiologic state. They constantly survey their environment for pathologic alterations associated with injury or diseases. For decades, researchers have investigated the role of microglia under different pathologic conditions, using approaches aiming to inhibit or eliminate these phagocytic cells. However, until recently, methods have failed to achieve complete depletion. Moreover, treatments often affected other cells, making unequivocal conclusions from these studies difficult. Recently, we have shown that inhibition of colony stimulating factor 1 receptor (CSF1R) by oral treatment with PLX5622 containing chow enables complete depletion of retinal microglia and almost complete microglia depletion in the optic nerve without affecting peripheral macrophages or other cells. Using this approach, we investigated the role of microglia in neuroprotection in the retina and axon regeneration in the injured optic nerve under different conditions. Thus, this efficient, reliable and easy to use protocol presented here will enable researchers to unequivocally study the contribution of microglia on neurodegeneration and axon regeneration. This protocol can be also easily expanded to other paradigms of acute and chronic injury or diseases in the visual system.
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Affiliation(s)
- Alexander M Hilla
- Department of Cell Physiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany.,Division of Experimental Neurology, Department of Neurology Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Dietmar Fischer
- Department of Cell Physiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany.,Division of Experimental Neurology, Department of Neurology Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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11
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Reinhard J, Roll L, Faissner A. Tenascins in Retinal and Optic Nerve Neurodegeneration. Front Integr Neurosci 2017; 11:30. [PMID: 29109681 PMCID: PMC5660115 DOI: 10.3389/fnint.2017.00030] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 10/03/2017] [Indexed: 02/04/2023] Open
Abstract
Tenascins represent key constituents of the extracellular matrix (ECM) with major impact on central nervous system (CNS) development. In this regard, several studies indicate that they play a crucial role in axonal growth and guidance, synaptogenesis and boundary formation. These functions are not only important during development, but also for regeneration under several pathological conditions. Additionally, tenascin-C (Tnc) represents a key modulator of the immune system and inflammatory processes. In the present review article, we focus on the function of Tnc and tenascin-R (Tnr) in the diseased CNS, specifically after retinal and optic nerve damage and degeneration. We summarize the current view on both tenascins in diseases such as glaucoma, retinal ischemia, age-related macular degeneration (AMD) or diabetic retinopathy. In this context, we discuss their expression profile, possible functional relevance, remodeling of the interacting matrisome and tenascin receptors, especially under pathological conditions.
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Affiliation(s)
- Jacqueline Reinhard
- Department of Cell Morphology and Molecular Neurobiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Lars Roll
- Department of Cell Morphology and Molecular Neurobiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Andreas Faissner
- Department of Cell Morphology and Molecular Neurobiology, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
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12
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Neuroprotection in Glaucoma: Old and New Promising Treatments. Adv Pharmacol Sci 2017; 2017:4320408. [PMID: 30723498 PMCID: PMC5664381 DOI: 10.1155/2017/4320408] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 09/02/2017] [Accepted: 09/13/2017] [Indexed: 12/21/2022] Open
Abstract
Glaucoma is a major global cause of blindness, but the molecular mechanisms responsible for the neurodegenerative damage are not clear. Undoubtedly, the high intraocular pressure (IOP) and the secondary ischemic and mechanical damage of the optic nerve have a crucial role in retinal ganglion cell (RGC) death. Several studies specifically analyzed the events that lead to nerve fiber layer thinning, showing the importance of both intra- and extracellular factors. In parallel, many neuroprotective substances have been tested for their efficacy and safety in hindering the negative effects that lead to RGC death. New formulations of these compounds, also suitable for chronic oral administration, are likely to be used in clinical practice in the future along with conventional therapies, in order to control the progression of the visual impairment due to primary open-angle glaucoma (POAG). This review illustrates some of these old and new promising agents for the adjuvant treatment of POAG, with particular emphasis on forskolin and melatonin.
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13
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Shen J, Yang Q, Yu D, Wu J, Zhu Y, Guo W. Vulnerability study of myelinated and unmyelinated nerve fibers in acute ocular hypertension in rabbit. Mol Med Rep 2017; 16:6794-6802. [PMID: 28901515 PMCID: PMC5865837 DOI: 10.3892/mmr.2017.7474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 07/11/2017] [Indexed: 11/05/2022] Open
Abstract
In the current study, it was aimed to evaluate the changes in myelinated and unmyelinated nerve fibers in retinal ischemia-reperfusion injuries caused by acute ocular hypertension and to determine the sequence of these changes. Adult healthy New Zealand white rabbits were randomized to the hemodynamic group [n=12; used to determine the optimal intraocular pressure (IOP) for the subsequent experiments] and the hypertension group (n=6; 70-mmHg hypertension induced in one eye). IOP was adjusted using a cannula and saline. Doppler ultrasound was used to measure the velocity of the optic artery under different intraocular pressures. Immunohistochemistry for myelin basic protein (MBP) was performed. Apoptosis of retinal cells was detected by terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) assay. Electron microscopy was used to investigate the changes in myelinated and unmyelinated nerve fibers. IOP of the hypertension eyes was maintained at 70.2±1.0 mmHg, while IOP of control eyes was 7–14 mmHg. Doppler ultrasound demonstrated an obvious decline of peak systolic velocity and an increase of resistance index of retinal bloodstream under a 70-mmHg IOP. MBP immunohistochemistry and electron microscopy demonstrated obvious injuries to the myelin fibers. TUNEL indicated a significantly higher apoptosis rate in the hypertension eyes compared with control eyes. The apoptosis rate of retinal ganglion cells and bipolar cells in unmyelinated regions was higher than in myelinated regions. In conclusion, an IOP of 70 mmHg led to incomplete retinal ischemia but was the threshold for retinal ischemia, leading to obvious injuries to the myelin fibers.
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Affiliation(s)
- Jiying Shen
- Department of Ophthalmology, Shanghai Peace Eye Hospital, Shanghai 200437, P.R. China
| | - Qiang Yang
- Department of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai 200031, P.R. China
| | - Daoyi Yu
- Centre for Ophthalmology & Visual Science, The University of Western Australia, Perth, WA 6009, Australia
| | - Jihong Wu
- Department of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai 200031, P.R. China
| | - Yuanfang Zhu
- Department of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai 200031, P.R. China
| | - Wenyi Guo
- Department of Ophthalmology, Eye & ENT Hospital of Fudan University, Shanghai 200031, P.R. China
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14
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Leibinger M, Andreadaki A, Golla R, Levin E, Hilla AM, Diekmann H, Fischer D. Boosting CNS axon regeneration by harnessing antagonistic effects of GSK3 activity. Proc Natl Acad Sci U S A 2017; 114:E5454-E5463. [PMID: 28630333 PMCID: PMC5502600 DOI: 10.1073/pnas.1621225114] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Implications of GSK3 activity for axon regeneration are often inconsistent, if not controversial. Sustained GSK3 activity in GSK3S/A knock-in mice reportedly accelerates peripheral nerve regeneration via increased MAP1B phosphorylation and concomitantly reduces microtubule detyrosination. In contrast, the current study shows that lens injury-stimulated optic nerve regeneration was significantly compromised in these knock-in mice. Phosphorylation of MAP1B and CRMP2 was expectedly increased in retinal ganglion cell (RGC) axons upon enhanced GSK3 activity, but, surprisingly, no GSK3-mediated CRMP2 inhibition was detected in sciatic nerves, thus revealing a fundamental difference between central and peripheral axons. Conversely, genetic or shRNA-mediated conditional KO/knockdown of GSK3β reduced inhibitory phosphorylation of CRMP2 in RGCs and improved optic nerve regeneration. Accordingly, GSK3β KO-mediated neurite growth promotion and myelin disinhibition were abrogated by CRMP2 inhibition and largely mimicked in WT neurons upon expression of constitutively active CRMP2 (CRMP2T/A). These results underscore the prevalent requirement of active CRMP2 for optic nerve regeneration. Strikingly, expression of CRMP2T/A in GSK3S/A RGCs further boosted optic nerve regeneration, with axons reaching the optic chiasm within 3 wk. Thus, active GSK3 can also markedly promote axonal growth in central nerves if CRMP2 concurrently remains active. Similar to peripheral nerves, GSK3-mediated MAP1B phosphorylation/activation and the reduction of microtubule detyrosination contributed to this effect. Overall, these findings reconcile conflicting data on GSK3-mediated axon regeneration. In addition, the concept of complementary modulation of normally antagonistically targeted GSK3 substrates offers a therapeutically applicable approach to potentiate the regenerative outcome in the injured CNS.
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Affiliation(s)
- Marco Leibinger
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Anastasia Andreadaki
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Renate Golla
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Evgeny Levin
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Alexander M Hilla
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Heike Diekmann
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
| | - Dietmar Fischer
- Division of Experimental Neurology, Department of Neurology, Heinrich Heine University of Düsseldorf, 40225 Duesseldorf, Germany
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Microglia Are Irrelevant for Neuronal Degeneration and Axon Regeneration after Acute Injury. J Neurosci 2017; 37:6113-6124. [PMID: 28539419 DOI: 10.1523/jneurosci.0584-17.2017] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 03/29/2017] [Accepted: 04/26/2017] [Indexed: 12/15/2022] Open
Abstract
The role of microglia in degenerative and regenerative processes after damage of the nervous system remains ambiguous, partially due to the paucity of appropriate investigative methods. Here, we show that treatment with the pharmacological colony stimulating factor 1 receptor inhibitor PLX5622 specifically eliminated microglia in murine retinae and optic nerves with high efficiency. Interestingly, time course and extent of retinal ganglion cell (RGC) degeneration after optic nerve crush remained unaffected upon microglia depletion, although remnants of prelabeled apoptotic RGCs were not cleared from the retina in these animals. In addition, microglia depletion neither affected the induction of regeneration associated genes upon optic nerve injury nor the increased regenerative potential of RGCs upon lens injury (LI). However, although the repopulation of the optic nerve lesion site by astrocytes was significantly delayed upon microglia depletion, spontaneous and LI-induced axon regeneration were unaffected by PLX5622 treatment or peripheral macrophage depletion by clodronate liposome treatment. Only concurrent double depletion of microglia and infiltrated macrophages slightly, but significantly, compromised optic nerve regeneration. Therefore, microglia are not essentially involved in RGC degeneration or axonal regeneration after acute CNS injury.SIGNIFICANCE STATEMENT The roles of microglia, the phagocytosing cells of the CNS, and invading macrophages in degenerative and regenerative processes after injury are still controversial and insufficiently characterized. Here, we show that application of a CSF1R inhibitor eliminated virtually all microglia from the visual system, whereas macrophages were spared. Specific microglia depletion impaired the removal of dead labeled retinal ganglion cells after optic nerve crush, but remarkable had no influence on their degeneration. Similarly, optic nerve regeneration was completely unaffected, although repopulation of the lesion site by astrocytes was delayed significantly. Therefore, contrary to previous reports, this experimental approach revealed that microglia seemingly neither promote nor inhibit neuronal degeneration or axonal regrowth within the injured visual system.
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Li Y, He X, Li J, Ni F, Sun Q, Zhou Y. Proliferation and differentiation of direct co‑culture of bone marrow mesenchymal stem cells and pigmented cells from the ciliary margin. Mol Med Rep 2017; 15:3529-3534. [PMID: 28440470 PMCID: PMC5436198 DOI: 10.3892/mmr.2017.6481] [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: 02/14/2016] [Accepted: 02/07/2017] [Indexed: 12/23/2022] Open
Abstract
Damage of retinal ganglion cells (RGCs) is the major consequence of glaucoma and regeneration of RGCs is extremely difficult once the damage has occurred. Retinal stem cells (RSCs) are considered an ideal choice for RGC regeneration. Pigmented cells from the ciliary margin (PCMs) have great retinal differentiation potential and may be an ideal RSC candidate. However, the ciliary margin is too small, so the number of cells that can be obtained is limited. Bone marrow-derived mesenchymal stem cells (BMMSCs) are another type of stem cell that have been previously investigated for RGC regeneration. BMMSCs expand sufficiently, whereas the retinal differentiation of BMMSCs is insufficient. The aim of the present study was to investigate whether the co-culture of PCMs and BMMSCs may combine the advantages of both cell types to establish a novel and effective stem cell source for RGC regeneration. Primary rat PCMs and BMMSCs were isolated and co-cultured. Cell growth was observed by an inverted microscope and proliferation was monitored by an MTT assay. Cell cycle analysis was performed by using a flow cytometer, while the expression of the photoreceptor-specific homeobox gene (cone-rod homeobox, Crx) was determined by reverse transcription-quantitative polymerase chain reaction and western blot analysis. In addition, retinal differentiation was confirmed by immunofluorescence staining of major markers of retinal differentiation, including rhodopsin, visual system homeobox 2 and heparin sulfate. The co-cultured cells expanded successfully, in a similar way to BMMSCs. In addition, the expression of Crx and retinal markers were significantly upregulated following BMMSC and PCM co-culture. The results of the present study demonstrated that the co-culture of BMMSCs and PCMs may be used as a source of RSCs.
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Affiliation(s)
- Yan Li
- Department of Ophthalmology, No. 113 Hospital of PLA, Ningbo, Zhejiang 315000, P.R. China
| | - Xinzheng He
- Department of Ophthalmology, No. 113 Hospital of PLA, Ningbo, Zhejiang 315000, P.R. China
| | - Jun Li
- Department of Ophthalmology, No. 113 Hospital of PLA, Ningbo, Zhejiang 315000, P.R. China
| | - Fangfang Ni
- Department of Ophthalmology, No. 113 Hospital of PLA, Ningbo, Zhejiang 315000, P.R. China
| | - Qingqing Sun
- Department of Ophthalmology, No. 113 Hospital of PLA, Ningbo, Zhejiang 315000, P.R. China
| | - Yan Zhou
- Department of Glaucoma, Ningbo Eye Hospital, Ningbo, Zhejiang 315000, P.R. China
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17
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Longitudinal Analysis of Serum Autoantibody-Reactivities in Patients with Primary Open Angle Glaucoma and Optic Disc Hemorrhage. PLoS One 2016; 11:e0166813. [PMID: 28030545 PMCID: PMC5193360 DOI: 10.1371/journal.pone.0166813] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 11/04/2016] [Indexed: 11/06/2022] Open
Abstract
Background The aim of our current investigation was to analyze the autoantibody-reactivities of primary open angle glaucoma patients with optic disc hemorrhage as possibly correlated to disease progression by means of a protein microarray approach. Methods Sera of patients with primary open angle glaucoma and optic disc hemorrhage (n = 16) were collected directly after study inclusion (0 weeks) and after 2 weeks, 4 weeks and 12 weeks. As a control group patients with primary open angle glaucoma (n = 18) were used (0 weeks and 12 weeks). Microarrays were incubated and occurring antibody-antigen-reactions were visualized with fluorescence labeled anti-human-IgG secondary antibodies. To detect changes in autoantibodies spot intensities were digitized and compared. Results With respect to the immunoreactivity at 0 weeks level increment of anti-adaptor protein 1 complex subunit mu-1 antibodies and anti-SPRY domain-containing SOCS box protein 3 antibodies in sera of primary open angle patients with optic disc hemorrhage was detected. Linear trend analysis revealed a positive correlation with r ≥ 0.8 between antibody-level and time course. Control group show no relevant changes in the same period. Significant changes were found in time point 4 comparison between patient groups in anti-adaptor protein 1 complex subunit mu-1-level (p = 0.01). No significant changes in visual acuity were found. Conclusion With this approach we were able to detect autoimmune reactivities in sera of patients with primary open angle glaucoma and optic disc hemorrhage compared to patients without optic disc hemorrhage. These antibodies could give further insights into the pathogenesis and the autoimmune component of glaucomatous optic neuropathy.
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Hyper-IL-6: a potent and efficacious stimulator of RGC regeneration. Eye (Lond) 2016; 31:173-178. [PMID: 27886185 DOI: 10.1038/eye.2016.234] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 09/29/2016] [Indexed: 01/11/2023] Open
Abstract
Mature retinal ganglion cells (RGCs) normally fail to regenerate injured axons and die soon after optic nerve injury. Research over the last two decades has demonstrated that application of IL-6-like cytokines or activation of respective downstream signaling pathways promote neuroprotection and optic nerve regeneration. However, the overall beneficial effects of natural cytokines remain usually rather moderate, possibly due to intrinsic signaling pathway inhibitors, such as PTEN or SOCS3, or a limited expression of specific cytokine receptors in RGCs. It was recently demonstrated that directly targeting the gp130 receptor, a common signalling receptor of all IL-6-like cytokines, induces stronger RGC axon regeneration in vitro and in vivo than other known growth-promoting treatments such as inflammatory stimulation or PTEN knockout. Remarkably, continuous expression of hyper-IL-6 (hIL-6) upon intravitreal AAV injection after nerve injury enables long-distance axon regeneration, with some axons growing through the optic chiasm 6 weeks after optic nerve injury. Thus, AAV-mediated hIL-6 delivery is so far one of the strongest single, post-injury treatments for the promotion of optic nerve regeneration and may be suitable for the development of novel, clinically applicable therapeutic treatments for human patients.
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24(S)-Hydroxycholesterol protects the ex vivo rat retina from injury by elevated hydrostatic pressure. Sci Rep 2016; 6:33886. [PMID: 27653972 PMCID: PMC5032171 DOI: 10.1038/srep33886] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 09/05/2016] [Indexed: 01/01/2023] Open
Abstract
In the central nervous system, 24(S)-hydroxycholesterol (24(S)-HC) is an oxysterol synthesized from cholesterol by cholesterol 24-hydroxylase (CYP46A1) encoded by the cyp46a1 gene. In the present study using a rat ex vivo glaucoma model, we found that retinal 24(S)-HC synthesis is facilitated by pressure elevation. Moreover, we found that 24(S)-HC is neuroprotective against pressure mediated retinal degeneration. Quantitative real-time RT-PCR, ELISA, and immunohistochemistry revealed that elevated pressure facilitated the expression of cyp46a1 and CYP46A1. Immunohistochemically, the enhanced expression of CYP46A1 was mainly observed in retinal ganglion cells (RGC). LC-MS/MS revealed that 24(S)-HC levels increased in a pressure-dependent manner. Axonal injury and apoptotic RGC death induced by 75 mmHg high pressure was ameliorated by exogenously administered 1 μM 24(S)-HC. In contrast, voriconazole, a CYP46A1 inhibitor, was severely toxic even at normobaric pressure. Under normobaric conditions, 30 μM 24(S)-HC was required to prevent the voriconazole-mediated retinal damage. Taken together, our findings indicate that 24(S)-HC is facilitated by elevated pressure and plays a neuroprotective role under glaucomatous conditions, while voriconazole, an antifungal drug, is retinotoxic. 24(S)-HC and related compounds may serve as potential therapeutic targets for protecting glaucomatous eyes from pressure-induced injuries.
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20
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Ishikawa M, Yoshitomi T, Covey DF, Zorumski CF, Izumi Y. TSPO activation modulates the effects of high pressure in a rat ex vivo glaucoma model. Neuropharmacology 2016; 111:142-159. [PMID: 27596950 DOI: 10.1016/j.neuropharm.2016.09.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 08/12/2016] [Accepted: 09/01/2016] [Indexed: 01/02/2023]
Abstract
We previously reported that elevated pressure induces axonal swelling and facilitates the synthesis of the neurosteroid, allopregnanolone (AlloP), in the ex vivo rat retina. Exogenously applied AlloP attenuates the axonal swelling, suggesting that the neurosteroid plays a neuroprotective role against glaucomatous pressure-induced injuries, although mechanisms underlying neurosteroidogenesis have not been clarified. The aim of this study was to determine whether AlloP synthesis involves activation of translocator protein 18 kD (TSPO) and whether TSPO modulates pressure-induced retinal injury. Ex vivo rat retinas were exposed to various pressures (10, 35, or 75 mmHg) for 24 h. Expression of TSPO, 5α-reductase (5aRD), and AlloP was examined by quantitative real-time RT-PCR, ELISA, immunohistochemistry, and LC-MS/MS. We also examined the effects of TSPO ligands on AlloP synthesis and retinal damage. In this acute model, quantitative real-time RT-PCR and ELISA analyses revealed that elevated pressure facilitated TSPO expression. Similarly, these methods also detected enhanced 5aRD (mostly type II), which was observed in retinal ganglion cells (RGC) and the inner nuclear layer (INL). Atriol, a TSPO antagonist, suppressed pressure mediated AlloP synthesis and induced more severe histological changes in the inner retina when combined with elevated pressure. PK11195, a TSPO ligand that facilitates AlloP synthesis by itself, remarkably diminished pressure-mediated retinal degeneration. These results suggest that AlloP synthesis is induced by sequential activation of TSPO and 5aRD in an ex vivo glaucoma model, and that TSPO agonists may serve as potential therapeutic agents for the prevention of pressure-induced retinal damage.
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Affiliation(s)
- Makoto Ishikawa
- Department of Ophthalmology, Akita Graduate University School of Medicine, Akita, Japan.
| | - Takeshi Yoshitomi
- Department of Ophthalmology, Akita Graduate University School of Medicine, Akita, Japan
| | - Douglas F Covey
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, M.O, USA; The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, M.O, USA
| | - Charles F Zorumski
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, M.O, USA; Center for Brain Research in Mood Disorders, Washington University School of Medicine, St. Louis, M.O, USA; Department of Psychiatry, Washington University School of Medicine, St. Louis, M.O, USA
| | - Yukitoshi Izumi
- The Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, M.O, USA; Center for Brain Research in Mood Disorders, Washington University School of Medicine, St. Louis, M.O, USA; Department of Psychiatry, Washington University School of Medicine, St. Louis, M.O, USA
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21
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Becker S, Eastlake K, Jayaram H, Jones MF, Brown RA, McLellan GJ, Charteris DG, Khaw PT, Limb GA. Allogeneic Transplantation of Müller-Derived Retinal Ganglion Cells Improves Retinal Function in a Feline Model of Ganglion Cell Depletion. Stem Cells Transl Med 2016; 5:192-205. [PMID: 26718648 PMCID: PMC4729554 DOI: 10.5966/sctm.2015-0125] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 11/11/2015] [Indexed: 11/16/2022] Open
Abstract
Human Müller glia with stem cell characteristics (hMGSCs) have been shown to improve retinal function upon transplantation into rat models of retinal ganglion cell (RGC) depletion. However, their translational potential may depend upon successful engraftment and improvement of retinal function in experimental models with anatomical and functional features resembling those of the human eye. We investigated the effect of allogeneic transplantation of feline Müller glia with the ability to differentiate into cells expressing RGC markers, following ablation of RGCs by N-methyl-d-aspartate (NMDA). Unlike previous observations in the rat, transplantation of hMGSC-derived RGCs into the feline vitreous formed aggregates and elicited a severe inflammatory response without improving visual function. In contrast, allogeneic transplantation of feline MGSC (fMGSC)-derived RGCs into the vitrectomized eye improved the scotopic threshold response (STR) of the electroretinogram (ERG). Despite causing functional improvement, the cells did not attach onto the retina and formed aggregates on peripheral vitreous remnants, suggesting that vitreous may constitute a barrier for cell attachment onto the retina. This was confirmed by observations that cellular scaffolds of compressed collagen and enriched preparations of fMGSC-derived RGCs facilitated cell attachment. Although cells did not migrate into the RGC layer or the optic nerve, they significantly improved the STR and the photopic negative response of the ERG, indicative of increased RGC function. These results suggest that MGSCs have a neuroprotective ability that promotes partial recovery of impaired RGC function and indicate that cell attachment onto the retina may be necessary for transplanted cells to confer neuroprotection to the retina. Significance: Müller glia with stem cell characteristics are present in the adult human retina, but they do not have regenerative ability. These cells, however, have potential for development of cell therapies to treat retinal disease. Using a feline model of retinal ganglion cell (RGC) depletion, cell grafting methods to improve RGC function have been developed. Using cellular scaffolds, allogeneic transplantation of Müller glia-derived RGC promoted cell attachment onto the retina and enhanced retinal function, as judged by improvement of the photopic negative and scotopic threshold responses of the electroretinogram. The results suggest that the improvement of RGC function observed may be ascribed to the neuroprotective ability of these cells and indicate that attachment of the transplanted cells onto the retina is required to promote effective neuroprotection.
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Affiliation(s)
- Silke Becker
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Karen Eastlake
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Hari Jayaram
- National Institute for Health Research Biomedical Research Centre for Ophthalmology, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Megan F Jones
- Institute of Ophthalmology, University College London, London, United Kingdom
| | - Robert A Brown
- Institute of Orthopaedics and Musculoskeletal Science, University College London, London, United Kingdom
| | - Gillian J McLellan
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - David G Charteris
- National Institute for Health Research Biomedical Research Centre for Ophthalmology, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Peng T Khaw
- National Institute for Health Research Biomedical Research Centre for Ophthalmology, Institute of Ophthalmology, University College London, London, United Kingdom
| | - G Astrid Limb
- National Institute for Health Research Biomedical Research Centre for Ophthalmology, Institute of Ophthalmology, University College London, London, United Kingdom
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Jiang SM, Zeng LP, Zeng JH, Tang L, Chen XM, Wei X. β-III-Tubulin: a reliable marker for retinal ganglion cell labeling in experimental models of glaucoma. Int J Ophthalmol 2015; 8:643-52. [PMID: 26309856 DOI: 10.3980/j.issn.2222-3959.2015.04.01] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 01/22/2015] [Indexed: 02/05/2023] Open
Abstract
AIM To evaluate the reliability of β-III-Tubulin protein as a retinal ganglion cell (RGC) marker in the experimental glaucoma model. METHODS Glaucoma mouse models were established by injecting polystyrene microbeads into the anterior chamber of C57BL/6J mice, then their retinas were obtained 14d and 28d after the intraocular pressure (IOP) was elevated. Retinal flat mounts and sections were double-labeled by fluorogold (FG) and β-III-Tubulin antibody or single-labeled by β-III-Tubulin antibody, then RGCs were counted and compared respectively. RESULTS IOP of the injected eyes were elevated significantly and reached the peak at 22.8±0.7 mm Hg by day 14 after injection, then dropped to 11.3±0.7 mm Hg by day 28. RGC numbers counted by FG labeling and β-III-Tubulin antibody labeling were 64 807±4930 and 64614±5054 respectively in the control group, with no significant difference. By day 14, RGCs in the experimental group decreased significantly compared to the control group, but there was no significant difference between the FG labeling counting and the β-III-Tubulin antibody labeling counting either in the experimental group or in the control group. The result was similar by day 28, with further RGC loss. CONCLUSION Our result suggested that the β-III-Tubulin protein was not affected by IOP elevation and can be used as a reliable marker for RGC in experimental models of glaucoma.
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Affiliation(s)
- Shan-Ming Jiang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Li-Ping Zeng
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Ji-Hong Zeng
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Li Tang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Xiao-Ming Chen
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
| | - Xin Wei
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China
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Zhang J, Zhou YH. Effect of suction on macular thickness and retinal nerve fiber layer thickness during LASIK used femtosecond laser and Moria M2 microkeratome. Int J Ophthalmol 2015; 8:777-83. [PMID: 26309879 DOI: 10.3980/j.issn.2222-3959.2015.04.24] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 01/08/2015] [Indexed: 01/09/2023] Open
Abstract
AIM To compare the effect of suction on the macular thickness and retinal nerve fiber layer (RNFL) thickness during laser in situ keratomileusis (LASIK) used Ziemer FEMTO LDV femtosecond laser (Ziemer group) and Moria M2 automated microkeratome (Moria group) for flap creation. METHODS Fourier-domain optical coherence tomography (FD-OCT) was used to measure macular thickness, ganglion cell complex thickness and (RNFL) thickness of 204 eyes of 102 patients with the Ziemer femtosecond laser (102 eyes) and the Moria M2 microkeratome (102 eyes) before surgery and 30min; 1, 3d; 1wk; 1, 3mo; 1y after surgery. RESULTS The average foveal thickness and parafoveal retinal thickness 30min after the surgery were statistically more than that before surgery (Ziemer P<0.001, P=0.003 and Moria P=0.001, P=0.006) and the effect was less in the Ziemer group than that in the Moria group (P all<0.05). The ganglion cell complex thickness was not significantly changed in both groups (P all>0.05). The RNFL thickness was statistically less 30min after surgery in both groups (P=0.014, P<0.001), but the influence was less in Ziemer group than that in Moria group (P=0.038). However, the RNFL thickness had recovered to the preoperative level only 1d after surgery. CONCLUSION The suction of femtosecond laser and mechanical microkeratome led to the increase in macular central fovea thickness and the decrease in RNFL thickness values at the early stage after LASIK. The effect of suction on macular and the RNFL thicknesses in Ziemer group is smaller than that in Moria group.
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Affiliation(s)
- Jing Zhang
- Ophthalmic Center, Beijing Key Laboratory of Ophthalmology and Visual Science, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Yue-Hua Zhou
- Ophthalmic Center, Beijing Key Laboratory of Ophthalmology and Visual Science, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
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24
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Diekmann H, Kalbhen P, Fischer D. Active mechanistic target of rapamycin plays an ancillary rather than essential role in zebrafish CNS axon regeneration. Front Cell Neurosci 2015. [PMID: 26217179 PMCID: PMC4493654 DOI: 10.3389/fncel.2015.00251] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The developmental decrease of the intrinsic regenerative ability of the mammalian central nervous system (CNS) is associated with reduced activity of mechanistic target of rapamycin (mTOR) in mature neurons such as retinal ganglion cells (RGCs). While mTOR activity is further decreased upon axonal injury, maintenance of its pre-injury level, for instance by genetic deletion of the phosphatase and tensin homolog (PTEN), markedly promotes axon regeneration in mammals. The current study now addressed the question whether active mTOR might generally play a central role in axon regeneration by analyzing its requirement in regeneration-competent zebrafish. Remarkably, regulation of mTOR activity after optic nerve injury in zebrafish is fundamentally different compared to mammals. Hardly any activity was detected in naïve RGCs, whereas it was markedly increased upon axotomy in vivo as well as in dissociated cell cultures. After a short burst, mTOR activity was quickly attenuated, which is contrary to the requirements for axon regeneration in mammals. Surprisingly, mTOR activity was not essential for axonal growth per se, but correlated with cytokine- and PTEN inhibitor-induced neurite extension in vitro. Moreover, inhibition of mTOR using rapamycin significantly reduced axon regeneration in vivo and compromised functional recovery after optic nerve injury. Therefore, axotomy-induced mTOR activity is involved in CNS axon regeneration in zebrafish similar to mammals, although it plays an ancillary rather than essential role in this regeneration-competent species.
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Affiliation(s)
- Heike Diekmann
- Division of Experimental Neurology, Department of Neurology, Heinrich-Heine-University of Düsseldorf Düsseldorf, Germany
| | - Pascal Kalbhen
- Division of Experimental Neurology, Department of Neurology, Heinrich-Heine-University of Düsseldorf Düsseldorf, Germany
| | - Dietmar Fischer
- Division of Experimental Neurology, Department of Neurology, Heinrich-Heine-University of Düsseldorf Düsseldorf, Germany
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25
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Sugita M, Pircher M, Zotter S, Baumann B, Roberts P, Makihira T, Tomatsu N, Sato M, Vass C, Hitzenberger CK. Retinal nerve fiber bundle tracing and analysis in human eye by polarization sensitive OCT. BIOMEDICAL OPTICS EXPRESS 2015; 6:1030-54. [PMID: 25798324 PMCID: PMC4361419 DOI: 10.1364/boe.6.001030] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 02/19/2015] [Accepted: 02/20/2015] [Indexed: 05/18/2023]
Abstract
We present a new semi-automatic processing method for retinal nerve fiber bundle tracing based on polarization sensitive optical coherence tomography (PS-OCT) data sets. The method for tracing is based on a nerve fiber orientation map that covers the fovea and optic nerve head (ONH) regions. In order to generate the orientation map, two types of information are used: optic axis orientation based on polarization data, and complementary information obtained from nerve fiber layer (NFL) local thickness variation to reveal fiber bundle structures around the fovea. The corresponding two orientation maps are fused into a combined fiber orientation map. En face maps of NFL retardation, thickness, and unit-depth-retardation (UDR, equivalent to birefringence) are transformed into "along-trace" maps by using the obtained traces of the nerve fiber bundles. The method is demonstrated in the eyes of healthy volunteers, and as an example of further analyses utilizing this method, maps illustrating the gradients of NFL retardation, thickness, and UDR are demonstrated.
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Affiliation(s)
- Mitsuro Sugita
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
- Canon Inc., Tokyo,
Japan
| | - Michael Pircher
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
- Medical Imaging Cluster, Medical University of Vienna, Vienna,
Austria
| | - Stefan Zotter
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
| | - Bernhard Baumann
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
- Medical Imaging Cluster, Medical University of Vienna, Vienna,
Austria
| | - Philipp Roberts
- Department of Ophthalmology and Optometry, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
| | | | | | | | - Clemens Vass
- Department of Ophthalmology and Optometry, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
| | - Christoph K. Hitzenberger
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Währinger Gürtel 18-20, A-1090 Vienna,
Austria
- Medical Imaging Cluster, Medical University of Vienna, Vienna,
Austria
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26
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Wu Y, Xu F, Huang H, Chen L, Wen M, Jiang L, Lu L, Li L, Song D, Zeng S, Li L, Li M. Up-regulation of SKIP relates to retinal ganglion cells apoptosis after optic nerve crush in vivo. J Mol Histol 2014; 45:715-21. [PMID: 25074585 DOI: 10.1007/s10735-014-9589-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2014] [Accepted: 07/23/2014] [Indexed: 12/11/2022]
Abstract
Cell cycle re-entry is one of the key processes in neuronal apoptosis. Previous studies have shown that Ski-interacting protein (SKIP) played an important role in cell cycle re-entry. However, its expression and function in optic nerve injury are still with limited acquaintance. To investigate whether SKIP is involved in retinal ganglion cells (RGCs) death, we performed an optic nerve crush (ONC) model in adult rats. Western blot analysis revealed that up-regulation of SKIP was present in retina at 5 days after ONC. Immunofluorescent labeling indicated that up-regulated SKIP was found mainly in RGCs. We also investigated co-localization of SKIP with active-caspase-3 and TUNEL (apoptotic markers) -positive cells in the retina after ONC. In addition, the expression of SKIP was increased in parallel with P53 and P21 in retina after ONC. All these results suggested that up-regulation of SKIP in the retina was associated with RGCs death after ONC.
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Affiliation(s)
- Yu Wu
- Department of Ophthalmology, People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, Guangxi, People's Republic of China
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27
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Li N, Li Y, Duan X. Heat shock protein 72 confers protection in retinal ganglion cells and lateral geniculate nucleus neurons via blockade of the SAPK/JNK pathway in a chronic ocular-hypertensive rat model. Neural Regen Res 2014; 9:1395-401. [PMID: 25221598 PMCID: PMC4160872 DOI: 10.4103/1673-5374.137595] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2014] [Indexed: 01/03/2023] Open
Abstract
Optic nerve transection increased the expression of heat shock protein 72 (HSP72) in the lateral geniculate body, indicating that this protein is involved in the prevention of neuronal injury. Zinc sulfate and quercetin induced and inhibited the expression of HSP72, respectively. Intraperitoneal injections of zinc sulfate, SP600125 (c-Jun N-terminal kinase inhibitor), or quercetin were performed on retinal ganglion cells in a Wistar rat model of chronic ocular hypertension. Our results showed that compared with the control group, the expression of HSP72 in retinal ganglion cells and the lateral geniculate body was increased after the injection of zinc sulfate, but was decreased after the injection of quercetin. The expression of phosphorylated c-Jun N-terminal kinases and phosphorylated c-Jun were visible 3 days after injection in the control group, and reached a peak at 7 days. Zinc sulfate and SP600125 significantly decreased the expression of p-c-Jun, whereas quercetin significantly enhanced the expression of this protein. These results suggest that HSP72 protects retinal ganglion cells and lateral geniculate body in a rat model of chronic ocular hypertension from injury by blocking the activation of the stress-activated kinase/c-Jun N-terminal kinase apoptotic pathway.
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Affiliation(s)
- Ning Li
- Department of Ophthalmology, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui Province, China
| | - Yuehua Li
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
| | - Xuanchu Duan
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha, Hunan Province, China
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28
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Xu F, Huang H, Wu Y, Lu L, Jiang L, Chen L, Zeng S, Li L, Li M. Upregulation of Gem relates to retinal ganglion cells apoptosis after optic nerve crush in adult rats. J Mol Histol 2014; 45:565-71. [PMID: 24948002 DOI: 10.1007/s10735-014-9579-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/11/2014] [Indexed: 12/12/2022]
Abstract
GTP-binding protein Gem, a member protein of the Ras superfamily, can regulate actin cytoskeleton reorganization mediated by Rho-associated coiled-coil-containing protein kinase (ROCK). One attractive activity of the ROCK is playing a potential role in physiological and pathological process in retinal ganglion cells (RGCs) apoptosis. However, the function of Gem in retina is still with limited understanding. To investigate whether Gem is involved in optic nerve injury, we performed an optic nerve crush (ONC) model in adult rats. Western blot analysis indicated that Gem was significantly increased in the retina at the 3rd day after ONC. Meanwhile, double-immunofluorescent staining showed that Gem expression was mainly up-regulated in ganglion cell layer and co-localized with NeuN (a marker of RGCs). Additionally, the co-localizations of Gem/active-caspase-3 and Gem/TUNEL-positive cells were detected in RGCs. Furthermore, the expression of active-caspase-3 and TUNEL-positive cells was parallel with that of Gem. Finally, expression pattern of ROCK family (only ROCK2 but not ROCK1) was increased in the differentiated process, which was collected with the expression of GEM and active-caspase-3. Based on the present results, it is suggested that Gem might play a crucial role in RGCs apoptosis after ONC, which might be involved in ROCK pathway.
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Affiliation(s)
- Fan Xu
- Department of Ophthalmology, People's Hospital of Guangxi Zhuang Autonomous Region, Nanning, 530021, Guangxi, People's Republic of China
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29
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Osteopontin is induced by TGF-β2 and regulates metabolic cell activity in cultured human optic nerve head astrocytes. PLoS One 2014; 9:e92762. [PMID: 24718314 PMCID: PMC3981660 DOI: 10.1371/journal.pone.0092762] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 02/25/2014] [Indexed: 12/26/2022] Open
Abstract
The aqueous humor (AH) component transforming growth factor (TGF)-β2 is strongly correlated to primary open-angle glaucoma (POAG), and was shown to up-regulate glaucoma-associated extracellular matrix (ECM) components, members of the ECM degradation system and heat shock proteins (HSP) in primary ocular cells. Here we present osteopontin (OPN) as a new TGF-β2 responsive factor in cultured human optic nerve head (ONH) astrocytes. Activation was initially demonstrated by Oligo GEArray microarray and confirmed by semiquantitative (sq) RT-PCR, realtime RT-PCR and western blot. Expressions of most prevalent OPN receptors CD44 and integrin receptor subunits αV, α4, α 5, α6, α9, β1, β3 and β5 by ONH astrocytes were shown by sqRT-PCR and immunofluorescence labeling. TGF-β2 treatment did not affect their expression levels. OPN did not regulate gene expression of described TGF-β2 targets shown by sqRT-PCR. In MTS-assays, OPN had a time- and dose-dependent stimulating effect on the metabolic activity of ONH astrocytes, whereas TGF-β2 significantly reduced metabolism. OPN signaling via CD44 mediated a repressive outcome on metabolic activity, whereas signaling via integrin receptors resulted in a pro-metabolic effect. In summary, our findings characterize OPN as a TGF-β2 responsive factor that is not involved in TGF-β2 mediated ECM and HSP modulation, but affects the metabolic activity of astrocytes. A potential involvement in a protective response to TGF-β2 triggered damage is indicated, but requires further investigation.
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30
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Stutzki H, Leibig C, Andreadaki A, Fischer D, Zeck G. Inflammatory stimulation preserves physiological properties of retinal ganglion cells after optic nerve injury. Front Cell Neurosci 2014; 8:38. [PMID: 24574973 PMCID: PMC3922046 DOI: 10.3389/fncel.2014.00038] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 01/27/2014] [Indexed: 01/29/2023] Open
Abstract
Axonal injury in the optic nerve is associated with retinal ganglion cell (RGC) degeneration and irreversible loss of vision. However, inflammatory stimulation (IS) by intravitreal injection of Pam3Cys transforms RGCs into an active regenerative state enabling these neurons to survive injury and to regenerate axons into the injured optic nerve. Although morphological changes have been well studied, the functional correlates of RGCs transformed either into a de- or regenerating state at a sub-cellular level remain unclear. In the current study, we investigated the signal propagation in single intraretinal axons as well as characteristic activity features of RGCs in a naive, a degenerative or a regenerative state in ex vivo retinae 1 week after either optic nerve cut alone (ONC) or additional IS (ONC + IS). Recordings of single RGCs using high-density microelectrode arrays demonstrate that the mean intraretinal axonal conduction velocity significantly decreased within the first week after ONC. In contrast, when ONC was accompanied by regenerative Pam3Cys treatment the mean intraretinal velocity was undistinguishable from control RGCs, indicating a protective effect on the proximal axon. Spontaneous RGC activity decreased for the two most numerous RGC types (ON- and OFF-sustained cells) within one post-operative week, but did not significantly increase in RGCs after IS. The analysis of light-induced activity revealed that RGCs in ONC animals respond on average later and with fewer spikes than control RGCs. IS significantly improved the responsiveness of the two studied RGC types. These results show that the transformation into a regenerative state by IS preserves, at least transiently, the physiological functional properties of injured RGCs.
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Affiliation(s)
- Henrike Stutzki
- Neurochip Research Group, Natural and Medical Sciences Institute, University of Tübingen Reutlingen, Germany ; Graduate Training Centre of Neuroscience Tübingen, Germany
| | - Christian Leibig
- Neurochip Research Group, Natural and Medical Sciences Institute, University of Tübingen Reutlingen, Germany ; Graduate Training Centre of Neuroscience Tübingen, Germany
| | - Anastasia Andreadaki
- Department of Neurology, Experimental Neurology, Heinrich Heine University Düsseldorf Düsseldorf, Germany
| | - Dietmar Fischer
- Department of Neurology, Experimental Neurology, Heinrich Heine University Düsseldorf Düsseldorf, Germany
| | - Günther Zeck
- Neurochip Research Group, Natural and Medical Sciences Institute, University of Tübingen Reutlingen, Germany
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31
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Leibinger M, Andreadaki A, Diekmann H, Fischer D. Neuronal STAT3 activation is essential for CNTF- and inflammatory stimulation-induced CNS axon regeneration. Cell Death Dis 2013; 4:e805. [PMID: 24052073 PMCID: PMC3789169 DOI: 10.1038/cddis.2013.310] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 07/18/2013] [Accepted: 07/29/2013] [Indexed: 01/08/2023]
Abstract
CNS neurons, such as retinal ganglion cells (RGCs), do not normally regenerate injured axons, but instead undergo apoptotic cell death. Regenerative failure is due to inhibitory factors in the myelin and forming glial scar as well as due to an insufficient intrinsic capability of mature neurons to regrow axons. Nevertheless, RGCs can be transformed into an active regenerative state upon inflammatory stimulation (IS) in the inner eye, for instance by lens injury, enabling these RGCs to survive axotomy and to regenerate axons into the lesioned optic nerve. The beneficial effects of IS are mediated by various factors, including CNTF, LIF and IL-6. Consistently, IS activates various signaling pathways, such as JAK/STAT3 and PI3K/AKT/mTOR, in several retinal cell types. Using a conditional knockdown approach to specifically delete STAT3 in adult RGCs, we investigated the role of STAT3 in IS-induced neuroprotection and axon regeneration. Conditional STAT3 knockdown in RGCs did not affect the survival of RGCs after optic nerve injury compared with controls, but significantly reduced the neuroprotective effects of IS. STAT3 depletion significantly compromised CNTF-stimulated neurite growth in culture and IS-induced transformation of RGCs into an active regenerative state in vivo. As a consequence, IS-mediated axonal regeneration into the injured optic nerve was almost completely abolished in mice with STAT3 depleted in RGCs. In conclusion, STAT3 activation in RGCs is involved in neuroprotection and is a necessary prerequisite for optic nerve regeneration upon IS.
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Affiliation(s)
- M Leibinger
- Department of Neurology, Heinrich-Heine-University of Düsseldorf, Merowingerplatz 1a, Düsseldorf, Germany
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Paschalis EI, Chodosh J, Sperling RA, Salvador-Culla B, Dohlman C. A novel implantable glaucoma valve using ferrofluid. PLoS One 2013; 8:e67404. [PMID: 23840691 PMCID: PMC3696055 DOI: 10.1371/journal.pone.0067404] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 05/17/2013] [Indexed: 12/24/2022] Open
Abstract
Purpose To present a novel design of an implantable glaucoma valve based on ferrofluidic nanoparticles and to compare it with a well-established FDA approved valve. Setting Massachusetts Eye & Ear Infirmary, Boston, USA. Methods A glaucoma valve was designed using soft lithography techniques utilizing a water-immiscible magnetic fluid (ferrofluid) as a pressure-sensitive barrier to aqueous flow. Two rare earth micro magnets were used to calibrate the opening and closing pressure. In-vitro flow measurements were performed to characterize the valve and to compare it to Ahmed™ glaucoma valve. The reliability and predictability of the new valve was verified by pressure/flow measurements over a period of three months and X-ray diffraction (XRD) analysis over a period of eight weeks. In vivo assessment was performed in three rabbits. Results In the in vitro experiments, the opening and closing pressures of the valve were 10 and 7 mmHg, respectively. The measured flow/pressure response was linearly proportional and reproducible over a period of three months (1.8 µl/min at 12 mmHg; 4.3 µl/min at 16 mmHg; 7.6 µl/min at 21 mmHg). X-ray diffraction analysis did not show oxidization of the ferrofluid when exposed to water or air. Preliminary in vivo results suggest that the valve is biocompatible and can control the intraocular pressure in rabbits. Conclusions The proposed valve utilizes ferrofluid as passive, tunable constriction element to provide highly predictable opening and closing pressures while maintaining ocular tone. The ferrofluid maintained its magnetic properties in the aqueous environment and provided linear flow to pressure response. Our in-vitro tests showed reliable and reproducible results over a study period of three months. Preliminary in-vivo results were very promising and currently more thorough investigation of this device is underway.
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Affiliation(s)
- Eleftherios I Paschalis
- Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, United States of America.
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33
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Status and perspectives of neuroprotective therapies in glaucoma: the European Glaucoma Society White Paper. Cell Tissue Res 2013; 353:347-54. [PMID: 23712457 DOI: 10.1007/s00441-013-1637-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 04/12/2013] [Indexed: 12/12/2022]
Abstract
Glaucoma, a chronic progressive neuropathy and the most frequent cause of irreversible blindness worldwide, is commonly treated by medication or surgery aimed at lowering intraocular pressure. In view of the limited therapeutic options, the European Glaucoma Society (EGS) sponsored two Think Tank Meetings with the goal of assessing the current status and the overall perspectives for neuroprotective treatment strategies in glaucoma. The results of the meetings are summarized in this EGS White Paper.
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