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Li Z, Huang W, Zhang M, Huo Y, Li F, Song L, Wu S, Yang Q, Li X, Zhang J, Yang L, Hao J, Kang L. Minocycline-loaded nHAP/PLGA microspheres for prevention of injury-related corneal angiogenesis. J Nanobiotechnology 2024; 22:134. [PMID: 38549081 PMCID: PMC10979583 DOI: 10.1186/s12951-024-02317-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Accepted: 01/26/2024] [Indexed: 04/01/2024] Open
Abstract
BACKGROUND Corneal neovascularization (CoNV) threatens vision by disrupting corneal avascularity, however, current treatments, including pharmacotherapy and surgery, are hindered by limitations in efficacy and adverse effects. Minocycline, known for its anti-inflammatory properties, could suppress CoNV but faces challenges in effective delivery due to the cornea's unique structure. Therefore, in this study a novel drug delivery system using minocycline-loaded nano-hydroxyapatite/poly (lactic-co-glycolic acid) (nHAP/PLGA) nanoparticles was developed to improve treatment outcomes for CoNV. RESULTS Ultra-small nHAP was synthesized using high gravity technology, then encapsulated in PLGA by a double emulsion method to form nHAP/PLGA microspheres, attenuating the acidic by-products of PLGA degradation. The MINO@PLGA nanocomplex, featuring sustained release and permeation properties, demonstrated an efficient delivery system for minocycline that significantly inhibited the CoNV area in an alkali-burn model without exhibiting apparent cytotoxicity. On day 14, the in vivo microscope examination and ex vivo CD31 staining corroborated the inhibition of neovascularization, with the significantly smaller CoNV area (29.40% ± 6.55%) in the MINO@PLGA Tid group (three times daily) than that of the control group (86.81% ± 15.71%), the MINO group (72.42% ± 30.15%), and the PLGA group (86.87% ± 14.94%) (p < 0.05). Fluorescein sodium staining show MINO@PLGA treatments, administered once daily (Qd) and three times daily (Tid) demonstrated rapid corneal epithelial healing while the Alkali injury group and the DEX group showed longer healing times (p < 0.05). Additionally, compared to the control group, treatments with dexamethasone, MINO, and MINO@PLGA were associated with an increased expression of TGF-β as evidenced by immunofluorescence, while the levels of pro-inflammatory cytokines IL-1β and TNF-α demonstrated a significant decrease following alkali burn. Safety evaluations, including assessments of renal and hepatic biomarkers, along with H&E staining of major organs, revealed no significant cytotoxicity of the MINO@PLGA nanocomplex in vivo. CONCLUSIONS The novel MINO@PLGA nanocomplex, comprising minocycline-loaded nHAP/PLGA microspheres, has shown a substantial capacity for preventing CoNV. This study confirms the complex's ability to downregulate inflammatory pathways, significantly reducing CoNV with minimal cytotoxicity and high biosafety in vivo. Given these findings, MINO@PLGA stands as a highly promising candidate for ocular conditions characterized by CoNV.
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Affiliation(s)
- Zitong Li
- Department of Ophthalmology, Peking University First Hospital, Beijing, 100034, People's Republic of China
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China
| | - Wenpeng Huang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China
| | - Ming Zhang
- Department of Pathology, Peking University International Hospital, Beijing, China
| | - Yan Huo
- Department of Ophthalmology, PLA Rocket Force Characteristic Medical Center, Beijing, China
| | - Feifei Li
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Lele Song
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China
| | - Sitong Wu
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China
| | - Qi Yang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China
| | - Xiaoming Li
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Jianjun Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
| | - Liu Yang
- Department of Ophthalmology, Peking University First Hospital, Beijing, 100034, People's Republic of China.
| | - Jianchen Hao
- Department of Ophthalmology, Peking University First Hospital, Beijing, 100034, People's Republic of China.
| | - Lei Kang
- Department of Nuclear Medicine, Peking University First Hospital, Beijing, 100034, People's Republic of China.
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Driban M, Kedia N, Arora S, Chhablani J. Novel pharmaceuticals for the management of retinal vein occlusion and linked disorders. Expert Rev Clin Pharmacol 2023; 16:1125-1139. [PMID: 37933706 DOI: 10.1080/17512433.2023.2277882] [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: 08/09/2023] [Accepted: 10/27/2023] [Indexed: 11/08/2023]
Abstract
INTRODUCTION Retinal vein occlusion (RVO) is the second leading cause of blindness from retinal vascular disease behind diabetic retinopathy. Anti-vascular endothelial growth factor (VEGF) and glucocorticoid therapy are the cornerstones of pharmaceutical treatment for RVO. There is considerable interest in developing new pharmaceuticals in and out of these two classes to reduce costs, lower injection burden, and treat the occlusion itself, rather than the complications. AREAS COVERED In this review, we discuss novel pharmaceuticals for the treatment of RVO outside of current standard of care. We performed a comprehensive literature search encompassing pharmaceuticals that have recently been approved or have shown promising results in early clinical trials or animal models. EXPERT OPINION Anti-VEGF therapy remains the most efficacious treatment for RVO with a very favorable side effect profile. New biosimilars reduce costs while maintaining efficacy. Novel glucocorticoids may be a useful therapy in patients for whom anti-VEGF therapy has failed, or as an adjunct. Pharmaceuticals in other drug classes, particularly those with neuroprotective or regenerative properties, as well as those geared toward treating the occlusion itself, represent exciting options for early RVO therapy, but are likely years away from clinical relevance.
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Affiliation(s)
- Matthew Driban
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nikita Kedia
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Supriya Arora
- Bahamas Vision Center and Princess Margaret Hospital, Nassau, New Providence, Bahamas
| | - Jay Chhablani
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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3
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Combined drug triads for synergic neuroprotection in retinal degeneration. Biomed Pharmacother 2022; 149:112911. [DOI: 10.1016/j.biopha.2022.112911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/23/2022] Open
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4
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Wang SK, Cepko CL. Targeting Microglia to Treat Degenerative Eye Diseases. Front Immunol 2022; 13:843558. [PMID: 35251042 PMCID: PMC8891158 DOI: 10.3389/fimmu.2022.843558] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 01/31/2022] [Indexed: 12/29/2022] Open
Abstract
Microglia have been implicated in many degenerative eye disorders, including retinitis pigmentosa, age-related macular degeneration, glaucoma, diabetic retinopathy, uveitis, and retinal detachment. While the exact roles of microglia in these conditions are still being discovered, evidence from animal models suggests that they can modulate the course of disease. In this review, we highlight current strategies to target microglia in the eye and their potential as treatments for both rare and common ocular disorders. These approaches include depleting microglia with chemicals or radiation, reprogramming microglia using homeostatic signals or other small molecules, and inhibiting the downstream effects of microglia such as by blocking cytokine activity or phagocytosis. Finally, we describe areas of future research needed to fully exploit the therapeutic value of microglia in eye diseases.
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Affiliation(s)
- Sean K. Wang
- Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Constance L. Cepko
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, United States
- Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
- Howard Hughes Medical Institute, Chevy Chase, MD, United States
- *Correspondence: Constance L. Cepko,
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5
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Adamus G. Importance of Autoimmune Responses in Progression of Retinal Degeneration Initiated by Gene Mutations. Front Med (Lausanne) 2021; 8:672444. [PMID: 34926479 PMCID: PMC8674421 DOI: 10.3389/fmed.2021.672444] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 11/01/2021] [Indexed: 12/13/2022] Open
Abstract
Inherited retinal diseases (IRDs) are clinically and genetically heterogeneous rare disorders associated with retinal dysfunction and death of retinal photoreceptor cells, leading to blindness. Among the most frequent and severe forms of those retinopathies is retinitis pigmentosa (RP) that affects 1:4,000 individuals worldwide. The genes that have been implicated in RP are associated with the proteins present in photoreceptor cells or retinal pigment epithelium (RPE). Asymmetric presentation or sudden progression in retinal disease suggests that a gene mutation alone might not be responsible for retinal degeneration. Immune responses could directly target the retina or be site effect of immunity as a bystander deterioration. Autoantibodies against retinal autoantigens have been found in RP, which led to a hypothesis that autoimmunity could be responsible for the progression of photoreceptor cell death initiated by a genetic mutation. The other contributory factor to retinal degeneration is inflammation that activates the innate immune mechanisms, such as complement. If autoimmune responses contribute to the progression of retinopathy, this could have an implication on treatment, such as gene replacement therapy. In this review, we provide a perspective on the current role of autoimmunity/immunity in RP pathophysiology.
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Affiliation(s)
- Grazyna Adamus
- Ocular Immunology Laboratory, Casey Eye Institute, School of Medicine, Oregon Health and Science University, Portland, OR, United States
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6
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Hadziahmetovic M, Malek G. Age-Related Macular Degeneration Revisited: From Pathology and Cellular Stress to Potential Therapies. Front Cell Dev Biol 2021; 8:612812. [PMID: 33569380 PMCID: PMC7868387 DOI: 10.3389/fcell.2020.612812] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/23/2020] [Indexed: 12/12/2022] Open
Abstract
Age-related macular degeneration (AMD) is a neurodegenerative disease of the aging retina, in which patients experience severe vision loss. Therapies available to patients are limited and are only effective in a sub-population of patients. Future comprehensive clinical care depends on identifying new therapeutic targets and adopting a multi-therapeutic approach. With this goal in mind, this review examines the fundamental concepts underlying the development and progression of AMD and re-evaluates the pathogenic pathways associated with the disease, focusing on the impact of injury at the cellular level, with the understanding that critical assessment of the literature may help pave the way to identifying disease-relevant targets. During this process, we elaborate on responses of AMD vulnerable cells, including photoreceptors, retinal pigment epithelial cells, microglia, and choroidal endothelial cells, based on in vitro and in vivo studies, to select stressful agents, and discuss current therapeutic developments in the field, targeting different aspects of AMD pathobiology.
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Affiliation(s)
- Majda Hadziahmetovic
- Duke Eye Center, Department of Ophthalmology, Duke University School of Medicine, Durham, NC, United States
| | - Goldis Malek
- Duke Eye Center, Department of Ophthalmology, Duke University School of Medicine, Durham, NC, United States.,Department of Pathology, Duke University School of Medicine, Durham, NC, United States
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Zhu Q, Xiao S, Hua Z, Yang D, Hu M, Zhu YT, Zhong H. Near Infrared (NIR) Light Therapy of Eye Diseases: A Review. Int J Med Sci 2021; 18:109-119. [PMID: 33390779 PMCID: PMC7738953 DOI: 10.7150/ijms.52980] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 10/15/2020] [Indexed: 12/18/2022] Open
Abstract
Near infrared (NIR) light therapy, or photobiomodulation therapy (PBMT), has gained persistent worldwide attention in recent years as a new novel scientific approach for therapeutic applications in ophthalmology. This ongoing therapeutic adoption of NIR therapy is largely propelled by significant advances in the fields of photobiology and bioenergetics, such as the discovery of photoneuromodulation by cytochrome c oxidase and the elucidation of therapeutic biochemical processes. Upon transcranial delivery, NIR light has been shown to significantly increase cytochrome oxidase and superoxide dismutase activities which suggests its role in inducing metabolic and antioxidant beneficial effects. Furthermore, NIR light may also boost cerebral blood flow and cognitive functions in humans without adverse effects. In this review, we highlight the value of NIR therapy as a novel paradigm for treatment of visual and neurological conditions, and provide scientific evidence to support the use of NIR therapy with emphasis on molecular and cellular mechanisms in eye diseases.
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Affiliation(s)
- Qin Zhu
- Department of Ophthalmology, the First Affiliated Hospital of Kunming Medical University, Kunming 650031, China
| | - Shuyuan Xiao
- Department of Ophthalmology, the First Affiliated Hospital of Kunming Medical University, Kunming 650031, China
| | - Zhijuan Hua
- Department of Ophthalmology, the First Affiliated Hospital of Kunming Medical University, Kunming 650031, China
| | - Dongmei Yang
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming 650021, China
| | - Min Hu
- Department of Ophthalmology, the Second People's Hospital of Yunnan Province, Kunming 650021, China
| | | | - Hua Zhong
- Department of Ophthalmology, the First Affiliated Hospital of Kunming Medical University, Kunming 650031, China
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8
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Gao W, Du J, Chi Y, Zhu R, Gao X, Yang L. Minocycline prevents the inflammatory response after retinal detachment, where microglia phenotypes being regulated through A20. Exp Eye Res 2020; 203:108403. [PMID: 33326811 DOI: 10.1016/j.exer.2020.108403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 12/14/2022]
Abstract
Retinal detachment (RD) is a severe sight-threatening complication that can be caused by a multitude of retinal diseases. It has been evidenced that minocycline exerts neuroprotective effects by targeting microglia in the pathogenesis of massive ocular lesions including RD, but mechanisms remain elusive. We carried out this research to elucidate the potential mediators that link RD-induced vision loss with microglia reactivity by discussing effects of minocycline on cytokine levels and A20, a negative regulator of inflammation. Minocycline or vehicle was intraperitoneally administrated immediately after RD and continued daily before animals being euthanized. The oxygen glucose deprivation assay was undertaken on the co-cultured BV-2 and 661W cells to mimic the condition of RD in vitro, where A20 siRNA was adopted to knock down the A20 expression in BV-2 cells. Photoreceptor cells apoptosis, inflammatory response and microglia activity following RD with or without minocycline were evaluated. Photoreceptor cells apoptosis and inflammatory response were induced after RD, which could be largely counteracted by minocycline. Minocycline postponed the migration and proliferation of microglia and facilitated their transition to the M2 subtype following RD. Blocking A20 expression in BV-2 cells with siRNA crippled the effect of minocycline. Collectively, minocycline yields a promoting effect on photoreceptor cells survival post-RD by modulating the transformation of microglia phenotypes, in which process A20 may play a "bridge" role.
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Affiliation(s)
- Wenna Gao
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China
| | - Jiantong Du
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China
| | - Ying Chi
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China
| | - Ruilin Zhu
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China
| | - Xinran Gao
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China
| | - Liu Yang
- Department of Ophthalmology, Peking University First Hospital, Beijing, PR China.
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9
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Yu H, Enayati S, Chang K, Cho K, Lee SW, Talib M, Zihlavnikova K, Xie J, Achour H, Fried SI, Utheim TP, Chen DF. Noninvasive Electrical Stimulation Improves Photoreceptor Survival and Retinal Function in Mice with Inherited Photoreceptor Degeneration. Invest Ophthalmol Vis Sci 2020; 61:5. [PMID: 32271885 PMCID: PMC7401948 DOI: 10.1167/iovs.61.4.5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose Neurons carry electrical signals and communicate via electrical activities. The therapeutic potential of electrical stimulation (ES) for the nervous system, including the retina, through improvement of cell survival and function has been noted. Here we investigated the neuroprotective and regenerative potential of ES in a mouse model of inherited retinal degeneration. Methods Rhodopsin-deficient (Rho−/−) mice received one or two sessions of transpalpebral ES or sham treatments for 7 consecutive days. Intraperitoneal injection of 5-ethynyl-2′-deoxyuridine was used to label proliferating cells. Weekly electroretinograms were performed to monitor retinal function. Retinal morphology, photoreceptor survival, and regeneration were evaluated in vivo using immunohistochemistry and genetic fate-mapping techniques. Müller cell (MC) cultures were employed to further define the optimal conditions of ES application. Results Noninvasive transpalpebral ES in Rho−/− mice improved photoreceptor survival and electroretinography function in vivo. ES also triggered residential retinal progenitor-like cells such as MCs to reenter the cell cycle, possibly producing new photoreceptors, as shown by immunohistochemistry and genetic fate-mapping techniques. ES directly stimulated cell proliferation and the expression of progenitor cell markers in MC cultures, at least partially through bFGF signaling. Conclusions Our study showed that transpalpebral ES improved photoreceptor survival and retinal function and induced the proliferation, probably photoreceptor regeneration, of MCs; this occurs via stimulation of the bFGF pathways. These results suggest the exciting possibility of applying noninvasive ES as a versatile tool for preventing photoreceptor loss and mobilizing endogenous progenitors for reversing vision loss in patients with photoreceptor degeneration.
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10
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Khanh Vu TH, Chen H, Pan L, Cho KS, Doesburg D, Thee EF, Wu N, Arlotti E, Jager MJ, Chen DF. CD4 + T-Cell Responses Mediate Progressive Neurodegeneration in Experimental Ischemic Retinopathy. THE AMERICAN JOURNAL OF PATHOLOGY 2020; 190:1723-1734. [PMID: 32389572 DOI: 10.1016/j.ajpath.2020.04.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 04/14/2020] [Accepted: 04/21/2020] [Indexed: 11/17/2022]
Abstract
Retinal ischemic events, which result from occlusion of the ocular vasculature share similar causes as those for central nervous system stroke and are among the most common cause of acute and irreversible vision loss in elderly patients. Currently, there is no established treatment, and the condition often leaves patients with seriously impaired vision or blindness. The immune system, particularly T-cell-mediated responses, is thought to be intricately involved, but the exact roles remain elusive. We found that acute ischemia-reperfusion injury to the retina induced a prolonged phase of retinal ganglion cell loss that continued to progress during 8 weeks after the procedure. This phase was accompanied by microglial activation and CD4+ T-cell infiltration into the retina. Adoptive transfer of CD4+ T cells isolated from diseased mice exacerbated retinal ganglion cell loss in mice with retinal reperfusion damage. On the other hand, T-cell deficiency or administration of T-cell or interferon-γ-neutralizing antibody attenuated retinal ganglion cell degeneration and retinal function loss after injury. These findings demonstrate a crucial role for T-cell-mediated responses in the pathogenesis of neural ischemia. These findings point to novel therapeutic targets of limiting or preventing neuron and function loss for currently untreatable conditions of optic neuropathy and/or central nervous system ischemic stroke.
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Affiliation(s)
- Thi Hong Khanh Vu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Huihui Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; The Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Li Pan
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Kin-Sang Cho
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Geriatric Research Education and Clinical Center, Office of Research and Development, Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts
| | - Djoeke Doesburg
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Eric F Thee
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Nan Wu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Department of Ophthalmology, Southwest Eye Hospital, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Elisa Arlotti
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts; Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Martine J Jager
- Department of Ophthalmology, Leiden University Medical Center, Leiden, the Netherlands
| | - Dong Feng Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts.
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11
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Xiao J, Adil MY, Chang K, Yu Z, Yang L, Utheim TP, Chen DF, Cho KS. Visual Contrast Sensitivity Correlates to the Retinal Degeneration in Rhodopsin Knockout Mice. Invest Ophthalmol Vis Sci 2020; 60:4196-4204. [PMID: 31618423 PMCID: PMC6795341 DOI: 10.1167/iovs.19-26966] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Purpose Clinical manifestations of photoreceptor degeneration include gradual thinning of the outer nuclear layer (ONL) and progressive reduction of electroretinogram (ERG) amplitudes and vision loss. Although preclinical evaluations of treatment strategies greatly depend on rodent models, the courses of these changes in mice remain unclear. We thus sought to investigate the temporal correlations in changes of spatial vision, ERG response, and ONL thickness in mice with progressive photoreceptor degeneration. Methods Adult wild-type (WT) mice and mice carrying rhodopsin deficiency (Rho−/−), a frequently used mouse model of human retinitis pigmentosa, were selected for investigation. Mouse spatial vision, including visual acuity (VA) and contrast sensitivity (CS), was determined using optomotor response (OMR) assays; ONL thickness was quantified by spectral-domain optical coherence tomography (SD-OCT), and ERG was performed to evaluate retinal functions. The mice were killed when they were 14 weeks old, and the cone photoreceptors in retinal sections were counted. Results Spatial vision, ONL thickness, and ERG amplitudes remained stable in WT mice at all examined time points. While 6-week-old Rho−/− mice had VA, CS, as well as ERG responses similar to those of WT mice, progressive reductions in the spatial vision and retinal functions were recorded thereafter. Most tested 12-week-old Rho−/− mice had no visual-evoked OMR and ERG responses. Moreover, CS, but not VA, displayed a linear decline that was closely associated with ONL thinning, reduction of ERG amplitudes, and loss of cones. Conclusions We presented a comprehensive study of the relation between the changes of spatial vision, retinal function, and ONL thickness in postnatal week (PW)6 to PW12 Rho−/− mice. CS is a more sensitive indicator of spatial vision compared to VA, although both are required as separate parameters for monitoring the visual changes in retina undergoing photoreceptor degeneration.
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Affiliation(s)
- Jiaxin Xiao
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.,Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Muhammed Yasin Adil
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.,Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Karen Chang
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.,National Taiwan University, Taiwan
| | - Zicheng Yu
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
| | - Lanbo Yang
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
| | - Tor P Utheim
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Norway
| | - Dong Feng Chen
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States
| | - Kin-Sang Cho
- Schepens Eye Research Institute of Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, United States.,Geriatric Research Education and Clinical Center, Office of Research and Development, Edith Nourse Rogers Memorial Veterans Hospital, Bedford, Massachusetts, United States
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12
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Abstract
Microglia, the primary resident immune cell type, constitute a key population of glia in the retina. Recent evidence indicates that microglia play significant functional roles in the retina at different life stages. During development, retinal microglia regulate neuronal survival by exerting trophic influences and influencing programmed cell death. During adulthood, ramified microglia in the plexiform layers interact closely with synapses to maintain synaptic structure and function that underlie the retina's electrophysiological response to light. Under pathological conditions, retinal microglia participate in potentiating neurodegeneration in diseases such as glaucoma, retinitis pigmentosa, and age-related neurodegeneration by producing proinflammatory neurotoxic cytokines and removing living neurons via phagocytosis. Modulation of pathogenic microglial activation states and effector mechanisms has been linked to neuroprotection in animal models of retinal diseases. These findings have led to the design of early proof-of-concept clinical trials with microglial modulation as a therapeutic strategy.
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Affiliation(s)
- Sean M. Silverman
- Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;,
| | - Wai T. Wong
- Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;,
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13
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Kogachi K, Wolfe JD, Kashani AH. Surgically Induced Focal Retinal Detachment Does Not Cause Detectable SD-OCT Retinal Changes in Normal Human Retina. Invest Ophthalmol Vis Sci 2017; 58:5270-5279. [PMID: 29049728 PMCID: PMC5644709 DOI: 10.1167/iovs.17-22737] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Induction of focal retinal detachment (RD) for subretinal delivery of stem cells and gene therapy is increasingly common. In order to determine if this procedure has an adverse impact on the retina, we use spectral-domain optical coherence tomography (SD-OCT) to evaluate the pre- and postoperative retinal anatomy of the incidentally detached normal retina surrounding large submacular hemorrhages (SMH) during surgical displacement procedures. Methods Retrospective, observational study of human subjects with monocular SMH evaluated before and after surgical displacement using clinical exam, fundus photography, and SD-OCT. Manual measurements of the inner retinal thickness (IRT), outer retinal thickness (ORT), and full retinal thickness (FRT) were made in regions involving the SMH and surrounding normal retina. Comparison of retinal thickness measurements was made using the Wilcoxon signed-rank test. Results Seven eyes were included in this study. All eyes successfully underwent surgical displacement of SMH. Visual acuity improved in 6/7 subjects and was unchanged in the remaining subject. Incidental RD of the normal retinal regions surrounding the SMH did not cause any significant change in IRT, ORT, or FRT that was detectable by SD-OCT. In contrast, mean FRT overlying regions with SMH was significantly greater before surgery compared to after displacement of SMH or normal adjacent retina. Conclusions Surgically induced focal RD does not cause detectable retinal changes in the incidentally detached normal retina surrounding large SMH. Therefore, surgical induction of focal RD should not be considered to have the same adverse impact on the retina as pathologic RD.
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Affiliation(s)
- Kaitlin Kogachi
- USC Roski Eye Institute, Keck School of Medicine of USC, Los Angeles, California, United States
| | - Jeremy D Wolfe
- Associated Retinal Consultants, Oakland University William Beaumont School of Medicine, Royal Oak, Michigan, United States
| | - Amir H Kashani
- USC Roski Eye Institute, Keck School of Medicine of USC, Los Angeles, California, United States
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Wubben TJ, Besirli CG, Zacks DN. Pharmacotherapies for Retinal Detachment. Ophthalmology 2016; 123:1553-62. [PMID: 27040150 DOI: 10.1016/j.ophtha.2016.02.040] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 02/15/2016] [Accepted: 02/24/2016] [Indexed: 01/02/2023] Open
Abstract
Retinal detachment is an important cause of visual loss. Currently, surgical techniques, including vitrectomy, scleral buckle, and pneumatic retinopexy, are the only means to repair retinal detachment and restore vision. However, surgical failure rates may be as high as 20%, and visual outcomes continue to vary secondary to multiple processes, including postoperative cystoid macular edema, epiretinal membrane formation, macular folds, and, ultimately, photoreceptor death. Therefore, pharmacotherapies are being sought to aid the success rates of modern surgical techniques and reduce or slow the degeneration of photoreceptors during retinal detachment. This review discusses potential therapeutic avenues that aid in retinal reattachment, reduce the rate of retinal redetachment by limiting proliferative vitreoretinopathy, and protect against photoreceptor cell death.
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Affiliation(s)
- Thomas J Wubben
- Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Cagri G Besirli
- Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - David N Zacks
- Kellogg Eye Center, Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan.
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15
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Falavarjani KG, Pourhabibi A, Aghdam KA, Hosseini SB, Modarres M, Pazouki A, Khanamiri HN. Determination of the toxicity of intravitreal minocycline in rabbit eyes. Cutan Ocul Toxicol 2015; 35:233-6. [DOI: 10.3109/15569527.2015.1081604] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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16
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Adalimumab Reduces Photoreceptor Cell Death in A Mouse Model of Retinal Degeneration. Sci Rep 2015; 5:11764. [PMID: 26170250 PMCID: PMC4501000 DOI: 10.1038/srep11764] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/02/2015] [Indexed: 12/29/2022] Open
Abstract
Growing evidence suggests that inflammation is involved in the progression of retinitis pigmentosa (RP) both in patients and in animal models. The aim of this study was to investigate the effect of Adalimumab, a monoclonal anti-TNFα antibody, on retinal degeneration in a murine model of human autosomal recessive RP, the rd10 mice at postnatal day (P) 18. In our housing conditions, rd10 retinas were seriously damaged at P18. Adalimumab reduced photoreceptor cell death, as determined by scoring the number of TUNEL-positive cells. In addition, nuclear poly (ADP) ribose (PAR) content, an indirect measure of PAR polymerase (PARP) activity, was also reduced after treatment. The blockade of TNFα ameliorated reactive gliosis, as visualized by decreased GFAP and IBA1 immunolabelling (Müller cell and microglial markers, respectively) and decreased up-regulation of TNFα gene expression. Adalimumab also improved antioxidant response by restoring total antioxidant capacity and superoxide dismutase activity. Finally, we observed that Adalimumab normalized energetic and metabolic pattern in rd10 mouse retinas. Our study suggests that the TNFα blockade could be a successful therapeutic approach to increase photoreceptor survival during the progression of RP. Further studies are needed to characterize its effect along the progression of the disease.
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17
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Li L, Eter N, Heiduschka P. The microglia in healthy and diseased retina. Exp Eye Res 2015; 136:116-30. [PMID: 25952657 DOI: 10.1016/j.exer.2015.04.020] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 04/28/2015] [Accepted: 04/29/2015] [Indexed: 12/25/2022]
Abstract
The microglia are the immune cells of the central nervous system and, also the retina. They fulfil several tasks of surveillance in the healthy retina. In case of an injury or disease, microglia become activated and tries to repair the damage. However, in a lot of cases it does not work, and microglia deteriorate the situation by releasing toxic and pro-inflammatory compounds. Moreover, they further promote degenerative processes by attacking and phagocytosing damaged neurones and photoreceptors that otherwise would possibly have the chance to survive. Such deleterious action of the microglia has been observed in degeneration of retinal ganglion cells and photoreceptors, and it takes place in hereditary diseases, infections as well as in case of traumatic or light injuries. Therefore, a number of attempts has been undertaken so far to inhibit the microglia, with varying success. The task remains to study behaviour of the microglia and their interaction with other retinal cell populations in more detail with respect to released factors and expressed receptors including the time points of the corresponding events. The goal has to be to find a better balance between helpful and detrimental actions of the microglia.
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Affiliation(s)
- Lu Li
- University of Münster Medical School, Department of Ophthalmology, Domagkstr. 15, D-48149 Münster, Germany
| | - Nicole Eter
- University of Münster Medical School, Department of Ophthalmology, Domagkstr. 15, D-48149 Münster, Germany
| | - Peter Heiduschka
- University of Münster Medical School, Department of Ophthalmology, Domagkstr. 15, D-48149 Münster, Germany.
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18
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Karlstetter M, Scholz R, Rutar M, Wong WT, Provis JM, Langmann T. Retinal microglia: just bystander or target for therapy? Prog Retin Eye Res 2014; 45:30-57. [PMID: 25476242 DOI: 10.1016/j.preteyeres.2014.11.004] [Citation(s) in RCA: 365] [Impact Index Per Article: 36.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 11/20/2014] [Accepted: 11/25/2014] [Indexed: 10/24/2022]
Abstract
Resident microglial cells can be regarded as the immunological watchdogs of the brain and the retina. They are active sensors of their neuronal microenvironment and rapidly respond to various insults with a morphological and functional transformation into reactive phagocytes. There is strong evidence from animal models and in situ analyses of human tissue that microglial reactivity is a common hallmark of various retinal degenerative and inflammatory diseases. These include rare hereditary retinopathies such as retinitis pigmentosa and X-linked juvenile retinoschisis but also comprise more common multifactorial retinal diseases such as age-related macular degeneration, diabetic retinopathy, glaucoma, and uveitis as well as neurological disorders with ocular manifestation. In this review, we describe how microglial function is kept in balance under normal conditions by cross-talk with other retinal cells and summarize how microglia respond to different forms of retinal injury. In addition, we present the concept that microglia play a key role in local regulation of complement in the retina and specify aspects of microglial aging relevant for chronic inflammatory processes in the retina. We conclude that this resident immune cell of the retina cannot be simply regarded as bystander of disease but may instead be a potential therapeutic target to be modulated in the treatment of degenerative and inflammatory diseases of the retina.
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Affiliation(s)
- Marcus Karlstetter
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Rebecca Scholz
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Cologne, Germany
| | - Matt Rutar
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
| | - Wai T Wong
- Unit on Neuron-Glia Interactions in Retinal Disease, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jan M Provis
- The John Curtin School of Medical Research, The Australian National University (ANU), Canberra, Australian Capital Territory, Australia
| | - Thomas Langmann
- Laboratory for Experimental Immunology of the Eye, Department of Ophthalmology, University of Cologne, Cologne, Germany.
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19
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Abcouwer SF, Lin CM, Shanmugam S, Muthusamy A, Barber AJ, Antonetti DA. Minocycline prevents retinal inflammation and vascular permeability following ischemia-reperfusion injury. J Neuroinflammation 2013; 10:149. [PMID: 24325836 PMCID: PMC3866619 DOI: 10.1186/1742-2094-10-149] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 11/24/2013] [Indexed: 12/21/2022] Open
Abstract
Background Many retinal diseases are associated with vascular dysfunction accompanied by neuroinflammation. We examined the ability of minocycline (Mino), a tetracycline derivative with anti-inflammatory and neuroprotective properties, to prevent vascular permeability and inflammation following retinal ischemia-reperfusion (IR) injury, a model of retinal neurodegeneration with breakdown of the blood-retinal barrier (BRB). Methods Male Sprague–Dawley rats were subjected to 45 min of pressure-induced retinal ischemia, with the contralateral eye serving as control. Rats were treated with Mino prior to and following IR. At 48 h after reperfusion, retinal gene expression, cellular inflammation, Evan’s blue dye leakage, tight junction protein organization, caspase-3 activation, and DNA fragmentation were measured. Cellular inflammation was quantified by flow-cytometric evaluation of retinal tissue using the myeloid marker CD11b and leukocyte common antigen CD45 to differentiate and quantify CD11b+/CD45low microglia, CD11b+/CD45hi myeloid leukocytes and CD11bneg/CD45hi lymphocytes. Major histocompatibility complex class II (MHCII) immunoreactivity was used to determine the inflammatory state of these cells. Results Mino treatment significantly inhibited IR-induced retinal vascular permeability and disruption of tight junction organization. Retinal IR injury significantly altered mRNA expression for 21 of 25 inflammation- and gliosis-related genes examined. Of these, Mino treatment effectively attenuated IR-induced expression of lipocalin 2 (LCN2), serpin peptidase inhibitor clade A member 3 N (SERPINA3N), TNF receptor superfamily member 12A (TNFRSF12A), monocyte chemoattractant-1 (MCP-1, CCL2) and intercellular adhesion molecule-1 (ICAM-1). A marked increase in leukostasis of both myeloid leukocytes and lymphocytes was observed following IR. Mino treatment significantly reduced retinal leukocyte numbers following IR and was particularly effective in decreasing the appearance of MHCII+ inflammatory leukocytes. Surprisingly, Mino did not significantly inhibit retinal cell death in this model. Conclusions IR induces a retinal neuroinflammation within hours of reperfusion characterized by inflammatory gene expression, leukocyte adhesion and invasion, and vascular permeability. Despite Mino significantly inhibiting these responses, it failed to block neurodegeneration.
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Affiliation(s)
- Steven F Abcouwer
- Department of Ophthalmology and Visual Sciences, University of Michigan Kellogg Eye Center, 1000 Wall Street, Ann Arbor, MI 48105, USA.
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20
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Baumgartner W, Baumgartner A. Rationale for an experimental treatment of retinitis pigmentosa: 140-Month test of hypothesis with one patient. Med Hypotheses 2013; 81:720-8. [DOI: 10.1016/j.mehy.2013.07.036] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 03/05/2013] [Accepted: 07/20/2013] [Indexed: 10/26/2022]
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21
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Sun C, Li XX, He XJ, Zhang Q, Tao Y. Neuroprotective effect of minocycline in a rat model of branch retinal vein occlusion. Exp Eye Res 2013; 113:105-16. [PMID: 23748101 DOI: 10.1016/j.exer.2013.05.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/01/2013] [Accepted: 05/21/2013] [Indexed: 01/06/2023]
Affiliation(s)
- Chuan Sun
- Department of Ophthalmology, People's Hospital, Peking University, Beijing, China
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22
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Yang X, Duan X. Minocycline inhibits the production of the precursor form of nerve growth factor by retinal microglial cells. Neural Regen Res 2013; 8:320-7. [PMID: 25206672 PMCID: PMC4107537 DOI: 10.3969/j.issn.1673-5374.2013.04.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 12/22/2012] [Indexed: 12/20/2022] Open
Abstract
A rat model of acute ocular hypertension was established by enhancing the perfusion of balanced salt solution in the anterior chamber of the right eye. Minocycline (90 mg/kg) was administered intraperitoneally into rats immediately after the operation for 3 consecutive days. Immunofluorescence, western blot assay and PCR detection revealed that the expression of the precursor form of nerve growth factor, nerve growth factor and the p75 neurotrophin receptor, and the mRNA expression of nerve growth factor and the p75 neurotrophin receptor, increased after acute ocular hypertension. The number of double-labeled CD11B- and precursor form of nerve growth factor-positive cells, glial fibrillary acidic protein- and p75 neurotrophin receptor-positive cells, glial fibrillary acidic protein- and caspase-3-positive cells in the retina markedly increased after acute ocular hypertension. The above-described expression decreased after minocycline treatment. These results suggested that minocycline inhibited the increased expression of the precursor form of nerve growth factor in microglia, the p75 neurotrophin receptor in astroglia, and protected cells from apoptosis.
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Affiliation(s)
- Xiaochun Yang
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | - Xuanchu Duan
- Department of Ophthalmology, Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
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23
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Chan CC, Smith WM. Inflammatory Response and Mediators in Retinal Injury. Retina 2013. [DOI: 10.1016/b978-1-4557-0737-9.00025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Wickham L, Lewis GP, Charteris DG, Fisher SK. Cellular Effects of Detachment and Reattachment on the Neural Retina and the Retinal Pigment Epithelium. Retina 2013. [DOI: 10.1016/b978-1-4557-0737-9.00029-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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25
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Cukras CA, Petrou P, Chew EY, Meyerle CB, Wong WT. Oral minocycline for the treatment of diabetic macular edema (DME): results of a phase I/II clinical study. Invest Ophthalmol Vis Sci 2012; 53:3865-74. [PMID: 22589436 DOI: 10.1167/iovs.11-9413] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Inflammation contributes significantly to the pathogenesis of diabetic macular edema (DME). In particular, retinal microglia demonstrate increased activation and aggregation in areas of DME. Study authors investigated the safety and potential efficacy of oral minocycline, a drug capable of inhibiting microglial activation, in the treatment of DME. METHODS A single-center, prospective, open-label phase I/II clinical trial enrolled five participants with fovea-involving DME who received oral minocycline 100 mg twice daily for 6 months. Main outcome measurements included best-corrected visual acuity (BCVA), central retinal subfield thickness (CST), and central macular volume using spectral domain optical coherence tomography (SD-OCT) and late leakage on fluorescein angiography (FA). RESULTS Findings indicated that the study drug was well tolerated and not associated with significant safety issues. In study eyes, mean BCVA improved continuously from baseline at 1, 2, 4, and 6 months by +1.0, +4.0, +4.0, and +5.8 letters, respectively, while mean retinal thickness (CST) on OCT decreased by -2.9%, -5.7%, -13.9, and -8.1% for the same time points. At month 6, mean area of late leakage on FA decreased by -34.4% in study eyes. Mean changes in contralateral fellow eyes also demonstrated similar trends. Improvements in outcome measures were not correlated with concurrent changes in systemic factors. CONCLUSIONS In this pilot proof-of-concept study of DME, minocycline as primary treatment was associated with improved visual function, central macular edema, and vascular leakage, comparing favorably with historical controls from previous studies. Microglial inhibition with oral minocycline may be a promising therapeutic strategy targeting the inflammatory etiology of DME. (ClinicalTrials.gov number, NCT01120899.).
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Affiliation(s)
- Catherine A Cukras
- Division of Epidemiology and Clinical Applications, National Institutes of Health, Bethesda, Maryland 20892, USA.
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26
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Rhee H, Cameron DJ. Lyme disease and pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS): an overview. Int J Gen Med 2012; 5:163-74. [PMID: 22393303 PMCID: PMC3292400 DOI: 10.2147/ijgm.s24212] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lyme disease (LD) is a complex, multisystemic illness. As the most common vector- borne disease in the United States, LD is caused by bacterial spirochete Borrelia burgdorferi sensu stricto, with potential coinfections from agents of anaplasmosis, babesiosis, and ehrlichiosis. Persistent symptoms and clinical signs reflect multiorgan involvement with episodes of active disease and periods of remission, not sparing the coveted central nervous system. The capability of microorganisms to cause and exacerbate various neuropsychiatric pathology is also seen in pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS), a recently described disorder attributed to bacterium Streptococcus pyogenes of group A beta-hemolytic streptococcus in which neurologic tics and obsessive-compulsive disorders are sequelae of the infection. In the current overview, LD and PANDAS are juxtaposed through a review of their respective infectious etiologies, clinical presentations, mechanisms of disease development, courses of illness, and treatment options. Future directions related to immunoneuropsychiatry are also discussed.
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27
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Miyake S, Sasaki M, Takahashi N, Tsubota K, Ozawa Y. Photo-damage mechanisms and anti-apoptotic effect of lutein in the mouse retina. Inflamm Regen 2012. [DOI: 10.2492/inflammregen.32.208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Lo ACY, Woo TTY, Wong RLM, Wong D. Apoptosis and other cell death mechanisms after retinal detachment: implications for photoreceptor rescue. ACTA ACUST UNITED AC 2011; 226 Suppl 1:10-7. [PMID: 21778775 DOI: 10.1159/000328206] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Retinal detachment (RD) is one of the most common causes of blindness. This separation of the neurosensory retina from its underlying retinal pigment epithelium results in photoreceptor loss, which is the basis of permanent visual impairment. This review explores the various cell death mechanisms in photoreceptor death associated with RD. One of the major mechanisms is apoptosis, mediated by the intrinsic pathway, the Fas signalling pathway and/or the caspase-independent pathway. Other pathways of mechanisms include endoplasmic reticulum stress-mediated cell death, programmed necrosis and cytokine-related pathways. Understanding the mechanism of RD-associated photoreceptor death is likely to help us improve the current therapies or devise new strategies for this sight-threatening condition.
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Affiliation(s)
- Amy C Y Lo
- Eye Institute, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, SAR, China.
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Minocycline attenuates photoreceptor degeneration in a mouse model of subretinal hemorrhage microglial: inhibition as a potential therapeutic strategy. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:1265-77. [PMID: 21763674 DOI: 10.1016/j.ajpath.2011.05.042] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 05/09/2011] [Accepted: 05/26/2011] [Indexed: 01/09/2023]
Abstract
Hemorrhage under the neural retina (subretinal hemorrhage) can occur in the context of age-related macular degeneration and induce subsequent photoreceptor cell death and permanent vision loss. Current treatments with the objective of removing or displacing the hemorrhage are invasive and of mixed efficacy. We created a mouse model of subretinal hemorrhage to characterize the inflammatory responses and photoreceptor degeneration that occur in the acute aftermath of hemorrhage. It was observed that microglial infiltration into the outer retina commences as early as 6 hours after hemorrhage. Inflammatory cells progressively accumulate in the outer nuclear layer concurrently with photoreceptor degeneration and apoptosis. Administration of minocycline, an inhibitor of microglial activation, decreased microglial expression of chemotactic cytokines in vitro and reduced microglial infiltration and photoreceptor cell loss after subretinal hemorrhage in vivo. Inflammatory responses and photoreceptor atrophy occurred after subretinal hemorrhage, however, the degree of response and atrophy were similar between C3-deficient and C3-sufficient mice, indicating a limited role for complement-mediated processes. Our data indicate a role for inflammatory responses in driving photoreceptor cell loss in subretinal hemorrhage, and it is proposed that microglial inhibition may be beneficial in the treatment of subretinal hemorrhage.
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