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Carozza G, Zerti D, Tisi A, Ciancaglini M, Maccarrone M, Maccarone R. An overview of retinal light damage models for preclinical studies on age-related macular degeneration: identifying molecular hallmarks and therapeutic targets. Rev Neurosci 2024; 35:303-330. [PMID: 38153807 DOI: 10.1515/revneuro-2023-0130] [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: 10/21/2023] [Accepted: 11/19/2023] [Indexed: 12/30/2023]
Abstract
Age-related macular degeneration (AMD) is a complex, multifactorial disease leading to progressive and irreversible retinal degeneration, whose pathogenesis has not been fully elucidated yet. Due to the complexity and to the multiple features of the disease, many efforts have been made to develop animal models which faithfully reproduce the overall AMD hallmarks or that are able to mimic the different AMD stages. In this context, light damage (LD) rodent models of AMD represent a suitable and reliable approach to mimic the different AMD forms (dry, wet and geographic atrophy) while maintaining the time-dependent progression of the disease. In this review, we comprehensively reported how the LD paradigms reproduce the main features of human AMD. We discuss the capability of these models to broaden the knowledge in AMD research, with a focus on the mechanisms and the molecular hallmarks underlying the pathogenesis of the disease. We also critically revise the remaining challenges and future directions for the use of LD models.
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Affiliation(s)
- Giulia Carozza
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Darin Zerti
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Annamaria Tisi
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Marco Ciancaglini
- Department of Life, Health & Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Mauro Maccarrone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
- European Center for Brain Research (CERC)/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
| | - Rita Maccarone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, 67100 L'Aquila, Italy
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2
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Elbaz-Hayoun S, Rinsky B, Hagbi-Levi S, Grunin M, Chowers I. CCR1 mediates Müller cell activation and photoreceptor cell death in macular and retinal degeneration. eLife 2023; 12:e81208. [PMID: 37903056 PMCID: PMC10615370 DOI: 10.7554/elife.81208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2022] [Accepted: 10/04/2023] [Indexed: 11/01/2023] Open
Abstract
Mononuclear cells are involved in the pathogenesis of retinal diseases, including age-related macular degeneration (AMD). Here, we examined the mechanisms that underlie macrophage-driven retinal cell death. Monocytes were extracted from patients with AMD and differentiated into macrophages (hMdɸs), which were characterized based on proteomics, gene expression, and ex vivo and in vivo properties. Using bioinformatics, we identified the signaling pathway involved in macrophage-driven retinal cell death, and we assessed the therapeutic potential of targeting this pathway. We found that M2a hMdɸs were associated with retinal cell death in retinal explants and following adoptive transfer in a photic injury model. Moreover, M2a hMdɸs express several CCRI (C-C chemokine receptor type 1) ligands. Importantly, CCR1 was upregulated in Müller cells in models of retinal injury and aging, and CCR1 expression was correlated with retinal damage. Lastly, inhibiting CCR1 reduced photic-induced retinal damage, photoreceptor cell apoptosis, and retinal inflammation. These data suggest that hMdɸs, CCR1, and Müller cells work together to drive retinal and macular degeneration, suggesting that CCR1 may serve as a target for treating these sight-threatening conditions.
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Affiliation(s)
- Sarah Elbaz-Hayoun
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of JerusalemJerusalemIsrael
| | - Batya Rinsky
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of JerusalemJerusalemIsrael
| | - Shira Hagbi-Levi
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of JerusalemJerusalemIsrael
| | - Michelle Grunin
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of JerusalemJerusalemIsrael
| | - Itay Chowers
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of JerusalemJerusalemIsrael
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3
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Ahmad I, Naqvi RA, Valverde A, Naqvi AR. LncRNA MALAT1/microRNA-30b axis regulates macrophage polarization and function. Front Immunol 2023; 14:1214810. [PMID: 37860007 PMCID: PMC10582718 DOI: 10.3389/fimmu.2023.1214810] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Accepted: 09/21/2023] [Indexed: 10/21/2023] Open
Abstract
Macrophages (Mφ) are long-lived myeloid cells that can polarize towards the proinflammatory M1 or proresolving M2 phenotype to control diverse biological processes such as inflammation, tissue damage, and regeneration. Noncoding RNA are a class of nonprotein-coding transcriptome with numerous interdependent biological roles; however, their functional interaction in the regulation of Mφ polarization and immune responses remain unclear. Here, we show antagonistic relationship between lncRNA (MALAT1) and microRNA (miR-30b) in shaping macrophage polarization and immune functions. MALAT1 expression displays a time-dependent induction during Mφ differentiation and, upon challenge with TLR4 agonist (E. coli LPS). MALAT1 knockdown promoted the expression of M2Mφ markers without affecting M1Mφ markers, suggesting that MALAT1 favors the M1 phenotype by suppressing M2 differentiation. Compared to the control, MALAT1 knockdown resulted in reduced antigen uptake and processing, bacterial phagocytosis, and bactericidal activity, strongly supporting its critical role in regulating innate immune functions in Mφ. Consistent with this, MALAT1 knockdown showed impaired cytokine secretion upon challenge with LPS. Importantly, MALAT1 exhibit an antagonistic expression pattern with all five members of the miR-30 family during M2 Mφ differentiation. Dual-luciferase assays validated a novel sequence on MALAT1 that interacts with miR-30b, a microRNA that promotes the M2 phenotype. Phagocytosis and antigen processing assays unequivocally demonstrated that MALAT1 and miR-30b are functionally antagonistic. Concurrent MALAT1 knockdown and miR-30b overexpression exhibited the most significant attenuation in both assays. In human subjects with periodontal disease and murine model of ligature-induced periodontitis, we observed higher levels of MALAT1, M1Mφ markers and downregulation of miR-30b expression in gingival tissues suggesting a pro-inflammatory function of MALAT1 in vivo. Overall, we unraveled the role of MALAT1 in Mφ polarization and delineated the underlying mechanism of its regulation by involving MALAT-1-driven miR-30b sequestration.
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Affiliation(s)
| | | | | | - Afsar R. Naqvi
- Mucosal Immunology Lab, College of Dentistry, University of Illinois at Chicago, Chicago, IL, United States
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4
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Lepre CC, Russo M, Trotta MC, Petrillo F, D'Agostino FA, Gaudino G, D'Amico G, Campitiello MR, Crisci E, Nicoletti M, Gesualdo C, Simonelli F, D'Amico M, Hermenean A, Rossi S. Inhibition of Galectins and the P2X7 Purinergic Receptor as a Therapeutic Approach in the Neurovascular Inflammation of Diabetic Retinopathy. Int J Mol Sci 2023; 24:ijms24119721. [PMID: 37298672 DOI: 10.3390/ijms24119721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 06/12/2023] Open
Abstract
Diabetic retinopathy (DR) is the most frequent microvascular retinal complication of diabetic patients, contributing to loss of vision. Recently, retinal neuroinflammation and neurodegeneration have emerged as key players in DR progression, and therefore, this review examines the neuroinflammatory molecular basis of DR. We focus on four important aspects of retinal neuroinflammation: (i) the exacerbation of endoplasmic reticulum (ER) stress; (ii) the activation of the NLRP3 inflammasome; (iii) the role of galectins; and (iv) the activation of purinergic 2X7 receptor (P2X7R). Moreover, this review proposes the selective inhibition of galectins and the P2X7R as a potential pharmacological approach to prevent the progression of DR.
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Affiliation(s)
- Caterina Claudia Lepre
- "Aurel Ardelean" Institute of Life Sciences, Vasile Goldis Western University of Arad, 310144 Arad, Romania
| | - Marina Russo
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Maria Consiglia Trotta
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Francesco Petrillo
- Ph.D. Course in Translational Medicine, Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Fabiana Anna D'Agostino
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Gennaro Gaudino
- School of Anesthesia and Intensive Care, University of Foggia, 71122 Foggia, Italy
| | | | - Maria Rosaria Campitiello
- Department of Obstetrics and Gynecology and Physiopathology of Human Reproduction, ASL Salerno, 84124 Salerno, Italy
| | - Erminia Crisci
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Maddalena Nicoletti
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Carlo Gesualdo
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Francesca Simonelli
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Michele D'Amico
- Department of Experimental Medicine, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
| | - Anca Hermenean
- "Aurel Ardelean" Institute of Life Sciences, Vasile Goldis Western University of Arad, 310144 Arad, Romania
| | - Settimio Rossi
- Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania "Luigi Vanvitelli", 80138 Naples, Italy
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Tisi A, Carozza G, Leuti A, Maccarone R, Maccarrone M. Dysregulation of Resolvin E1 Metabolism and Signaling in a Light-Damage Model of Age-Related Macular Degeneration. Int J Mol Sci 2023; 24:ijms24076749. [PMID: 37047721 PMCID: PMC10095591 DOI: 10.3390/ijms24076749] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/31/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
Resolvin E1 (RvE1) is an eicosapentaenoic acid-derived lipid mediator involved in the resolution of inflammation. Here, we investigated whether RvE1 alterations may occur in an animal model of age-related macular degeneration (AMD). To this end, Sprague Dawley albino rats underwent light damage (LD), and retinas and serum were analyzed immediately or seven days after treatment. Western blot of retinas showed that the RvE1 receptor ChemR23 and the RvE1 metabolic enzymes 5-LOX and COX-2 were unchanged immediately after LD, but they were significantly up-regulated seven days later. Instead, the RvE1 receptor BLT1 was not modulated by LD, and neither was the RvE1 degradative enzyme 15-PGDH. Moreover, ChemR23, 5-LOX, COX-2 and BLT1 were found to be more expressed in the inner retina under all experimental conditions, as observed through ImageJ plot profile analysis. Of note, amacrine cells highly expressed BLT1, while ChemR23 was highly expressed in the activated microglia of the outer retina. ELISA assays also showed that LD rats displayed significantly higher circulating levels and reduced retinal levels of RvE1 compared to controls. Altogether, our data indicate that RvE1 metabolism and signaling are modulated in the LD model, suggesting a potentially relevant role of this pathway in AMD.
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Affiliation(s)
- Annamaria Tisi
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy
| | - Giulia Carozza
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy
| | - Alessandro Leuti
- Department of Medicine, Campus Bio-Medico University of Rome, 00128 Rome, Italy
- European Center for Brain Research (CERC)/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
| | - Rita Maccarone
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy
| | - Mauro Maccarrone
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, 67100 L’Aquila, Italy
- European Center for Brain Research (CERC)/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
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6
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Microglia in Cultured Porcine Retina: Qualitative Immunohistochemical Analyses of Reactive Microglia in the Outer Retina. Int J Mol Sci 2023; 24:ijms24010871. [PMID: 36614320 PMCID: PMC9820911 DOI: 10.3390/ijms24010871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/26/2022] [Accepted: 12/29/2022] [Indexed: 01/05/2023] Open
Abstract
A late stage of several retinal disorders is retinal detachment, a complication that results in rapid photoreceptor degeneration and synaptic damages. Experimental retinal detachment in vivo is an invasive and complicated method performed on anesthetized animals. As retinal detachment may result in visual impairment and blindness, research is of fundamental importance for understanding degenerative processes. Both morphological and ethical issues make the porcine retina a favorable organotypic model for studies of the degenerative processes that follow retinal detachment. In the cultured retina, photoreceptor degeneration and synaptic injuries develop rapidly and correlate with resident microglial cells' transition into a reactive phenotype. In this immunohistochemical study, we have begun to analyze the transition of subsets of reactive microglia which are known to localize close to the outer plexiform layer (OPL) in degenerating in vivo and in vitro retina. Biomarkers for reactive microglia included P2Ry12, CD63 and CD68 and the general microglial markers were CD11b, Iba1 and isolectin B4 (IB4). The reactive microglia markers labeled microglia subpopulations, suggesting that protective or harmful reactive microglia may be present simultaneously in the injured retina. Our findings support the usage of porcine retina cultures for studies of photoreceptor injuries related to retinal detachment.
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7
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Farajipour H, Sadr S, Matin HR, Aschner M, Asemi Z, Banikazemi Z, Mirzaei H, Taghizadeh M. Therapeutic effect of probiotics on metabolic indices and clinical signs in age-related macular degeneration. J Immunoassay Immunochem 2022; 44:229-241. [PMID: 36576143 DOI: 10.1080/15321819.2022.2159765] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Probiotics positively influence age-related macular degeneration (ARMD) given their propensity to attenuate oxidative and inflammatory stress. We addressed the impact of probiotics on metabolic profiles, clinical indices, inflammatory and oxidative stress parameters in ARMD patients. We performed a randomized, double-blind, placebo-controlled trial analyzing 57 subjects with ARMD aged between 50 and 85 years. Subjects were randomized into two groups, and received daily for 8 weeks either probiotic capsule or placebo. Fasting blood samples were obtained at baseline and after the 8-week intervention for the determination of metabolic profiles and oxidative stress biomarkers. After the 8-week intervention, compared with the placebo, probiotic supplementation significantly increased means HDL-cholesterol (Probiotic group: +3.86±4.42 vs. Placebo group: -0.55±4.93 mg/dL, P = .001), plasma total antioxidant capacity (TAC) (Probiotic group: +77.43±168.30 vs. Placebo group: -23.12±169.22 mmol/L, P = .02) and significantly decreased malondialdehyde (MDA) levels (Probiotic group: -0.18±0.46 vs. Placebo group: +0.18±0.25 µmol/L, P = .001). There was no significant effect of probiotic administration on other metabolic profiles and clinical symptoms. Overall, an eight-week probiotic administration among ARMD patients had beneficial effects on TAC, MDA and HDL-cholesterol levels; however, it did not affect clinical signs and other metabolic profiles.
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Affiliation(s)
- Hasan Farajipour
- Department of Ophthalmology, School of Medicine, Matini Hospital, Kashan University of Medical Sciences, Kashan, Iran
| | - Saeed Sadr
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Hamid Reza Matin
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Forchheimer 209, 1300 Morris Park Avenue, Bronx, New York 10461, USA
| | - Zatollah Asemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
| | - Zarrin Banikazemi
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.,Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
| | - Mohsen Taghizadeh
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran
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8
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Nortey A, Garces K, Carmy-Bennun T, Hackam AS. The cytokine IL-27 reduces inflammation and protects photoreceptors in a mouse model of retinal degeneration. J Neuroinflammation 2022; 19:216. [PMID: 36064575 PMCID: PMC9446869 DOI: 10.1186/s12974-022-02576-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 08/25/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Retinal degenerative diseases are a group of conditions characterized by photoreceptor death and vision loss. Excessive inflammation and microglial activation contribute to the pathology of retinal degenerations and a major focus in the field is identifying more effective anti-inflammatory therapeutic strategies that promote photoreceptor survival. A major challenge to developing anti-inflammatory treatments is to selectively suppress detrimental inflammation while maintaining beneficial inflammatory responses. We recently demonstrated that endogenous levels of the IL-27 cytokine were upregulated in association with an experimental treatment that increased photoreceptor survival. IL-27 is a pleiotropic cytokine that regulates tissue reactions to infection, neuronal disease and tumors by inducing anti-apoptotic and anti-inflammatory genes and suppressing pro-inflammatory genes. IL-27 is neuroprotective in the brain, but its function during retinal degeneration has not been investigated. In this study, we investigated the effect of IL-27 in the rd10 mouse model of inherited photoreceptor degeneration. METHODS Male and female rd10 mice were randomly divided into experimental (IL-27) and control (saline) groups and intravitreally injected at age post-natal day (P) 18. Retina function was analyzed by electroretinograms (ERGs), visual acuity by optomotor assay, photoreceptor death by TdT-mediated dUTP nick-end labeling (TUNEL) assay, microglia/macrophage were detected by immunodetection of IBA1 and inflammatory mediators by cytoplex and QPCR analysis. The distribution of IL-27 in the retina was determined by immunohistochemistry on retina cross-sections and primary Muller glia cultures. RESULTS We demonstrate that recombinant IL-27 decreased photoreceptor death, increased retinal function and reduced inflammation in the rd10 mouse model of retinal degeneration. Furthermore, IL-27 injections led to lower levels of the pro-inflammatory proteins Ccl22, IL-18 and IL-12. IL-27 expression was localized to Muller glia and IL-27 receptors to microglia, which are key cell types that regulate photoreceptor survival. CONCLUSION Our results identify for the first time anti-inflammatory and neuroprotective activities of IL-27 in a genetic model of retinal degeneration. These findings provide new insight into the therapeutic potential of anti-inflammatory cytokines as a treatment for degenerative diseases of the retina.
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Affiliation(s)
- Andrea Nortey
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Kimberly Garces
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Tal Carmy-Bennun
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Abigail S Hackam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
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9
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Microglia Impairs Proliferation and Induces Senescence In-Vitro in NGF Releasing Cells Used in Encapsulated Cell Biodelivery for Alzheimer's Disease Therapy. Int J Mol Sci 2022; 23:ijms23169011. [PMID: 36012296 PMCID: PMC9409429 DOI: 10.3390/ijms23169011] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/01/2022] [Accepted: 08/09/2022] [Indexed: 12/06/2022] Open
Abstract
There is no cure yet available for Alzheimer's disease (AD). We recently optimized encapsulated cell biodelivery (ECB) devices releasing human mature nerve growth factor (hmNGF), termed ECB-NGF, to the basal forebrain of AD patients. The ECB-NGF delivery resulted in increased CSF cholinergic markers, improved glucose metabolism, and positive effects on cognition in AD patients. However, some ECB-NGF implants showed altered hmNGF release post-explantation. To optimize the ECB-NGF platform for future therapeutic purposes, we initiated in-vitro optimization studies by exposing ECB-NGF devices to physiological factors present within the AD brain. We report here that microglia cells can impair hmNGF release from ECB-NGF devices in-vitro, which can be reversed by transferring the devices to fresh culture medium. Further, we exposed the hmNGF secreting human ARPE-19 cell line (NGC0211) to microglia (HMC3) conditioned medium (MCM; untreated or treated with IL-1β/IFNγ/Aβ40/Aβ42), and evaluated biochemical stress markers (ROS, GSH, ΔΨm, and Alamar Blue assay), cell death indicators (Annexin-V/PI), cell proliferation (CFSE retention and Ki67) and senescence markers (SA-β-gal) in NGC0211 cells. MCMs from activated microglia reduced cell proliferation and induced cell senescence in NGC0211 cells, which otherwise resist biochemical alterations and cell death. These data indicate a critical but reversible impact of activated microglia on NGC0211 cells.
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10
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Nashine S, Cohen P, Wan J, Kenney C. Effect of Humanin G (HNG) on inflammation in age-related macular degeneration (AMD). Aging (Albany NY) 2022; 14:4247-4269. [PMID: 35576057 PMCID: PMC9186758 DOI: 10.18632/aging.204074] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/25/2022] [Indexed: 12/03/2022]
Abstract
Inflammation plays a crucial role in the etiology and pathogenesis of AMD (Age-related Macular Degeneration). Humanin G (HNG) is a Mitochondrial Derived Peptide (MDP) that is cytoprotective in AMD and can protect against mitochondrial and cellular stress induced by damaged AMD mitochondria. The goal of this study was to test our hypothesis that inflammation-associated marker protein levels are increased in AMD and treatment with HNG leads to reduction in their protein levels. Humanin protein levels were measured in the plasma of AMD patients and normal subjects using ELISA assay. Humanin G was added to AMD and normal (control) cybrids which had identical nuclei from mitochondria-deficient ARPE-19 cells but differed in mitochondrial DNA (mtDNA) content derived from clinically characterized AMD patients and normal (control) subjects. Cell lysates were extracted from untreated and HNG-treated AMD and normal cybrids, and the Luminex XMAP multiplex assay was used to measure the levels of inflammatory proteins. AMD plasma showed reduced Humanin protein levels, but higher protein levels of inflammation markers compared to control plasma samples. In AMD RPE cybrid cells, Humanin G reduced the CD62E/ E-Selectin, CD62P/ P-Selectin, ICAM-1, TNF-α, MIP-1α, IFN–γ, IL-1β, IL-13, and IL-17A protein levels, thereby suggesting that Humanin G may rescue from mtDNA-mediated inflammation in AMD cybrids. In conclusion, we present novel findings that: A) show reduced Humanin protein levels in AMD plasma vs. normal plasma; B) suggest the role of inflammatory markers in AMD pathogenesis, and C) highlight the positive effects of Humanin G in reducing inflammation in AMD.
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Affiliation(s)
- Sonali Nashine
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California Irvine, Irvine, CA 92697, USA
| | - Pinchas Cohen
- Davis School of Gerontology, University of Southern California, Los Angeles, CA 90007, USA
| | - Junxiang Wan
- Davis School of Gerontology, University of Southern California, Los Angeles, CA 90007, USA
| | - Cristina Kenney
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California Irvine, Irvine, CA 92697, USA.,Department of Pathology and Laboratory Medicine, University of California, Irvine, CA 92697, USA
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11
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Jin N, Sha W, Gao L. Shaping the Microglia in Retinal Degenerative Diseases Using Stem Cell Therapy: Practice and Prospects. Front Cell Dev Biol 2021; 9:741368. [PMID: 34966736 PMCID: PMC8710684 DOI: 10.3389/fcell.2021.741368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 11/29/2021] [Indexed: 12/11/2022] Open
Abstract
Retinal degenerative disease (RDD) refers to a group of diseases with retinal degeneration that cause vision loss and affect people's daily lives. Various therapies have been proposed, among which stem cell therapy (SCT) holds great promise for the treatment of RDDs. Microglia are immune cells in the retina that have two activation phenotypes, namely, pro-inflammatory M1 and anti-inflammatory M2 phenotypes. These cells play an important role in the pathological progression of RDDs, especially in terms of retinal inflammation. Recent studies have extensively investigated the therapeutic potential of stem cell therapy in treating RDDs, including the immunomodulatory effects targeting microglia. In this review, we substantially summarized the characteristics of RDDs and microglia, discussed the microglial changes and phenotypic transformation of M1 microglia to M2 microglia after SCT, and proposed future directions for SCT in treating RDDs.
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Affiliation(s)
- Ni Jin
- Senior Department of Ophthalmology, The Third Medical Center of Chinese People's Liberation Army General Hospital, Beijing, China.,Department of Endocrinology, The Second Medical Center and National Clinical Research Center for Geriatric Diseases, Chinese People's Liberation Army General Hospital, Beijing, China
| | - Weiwei Sha
- Department of Endocrinology, The Second Medical Center and National Clinical Research Center for Geriatric Diseases, Chinese People's Liberation Army General Hospital, Beijing, China
| | - Lixiong Gao
- Senior Department of Ophthalmology, The Third Medical Center of Chinese People's Liberation Army General Hospital, Beijing, China
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12
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Kaur G, Singh NK. The Role of Inflammation in Retinal Neurodegeneration and Degenerative Diseases. Int J Mol Sci 2021; 23:ijms23010386. [PMID: 35008812 PMCID: PMC8745623 DOI: 10.3390/ijms23010386] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/24/2021] [Accepted: 12/28/2021] [Indexed: 12/19/2022] Open
Abstract
Retinal neurodegeneration is predominantly reported as the apoptosis or impaired function of the photoreceptors. Retinal degeneration is a major causative factor of irreversible vision loss leading to blindness. In recent years, retinal degenerative diseases have been investigated and many genes and genetic defects have been elucidated by many of the causative factors. An enormous amount of research has been performed to determine the pathogenesis of retinal degenerative conditions and to formulate the treatment modalities that are the critical requirements in this current scenario. Encouraging results have been obtained using gene therapy. We provide a narrative review of the various studies performed to date on the role of inflammation in human retinal degenerative diseases such as age-related macular degeneration, inherited retinal dystrophies, retinitis pigmentosa, Stargardt macular dystrophy, and Leber congenital amaurosis. In addition, we have highlighted the pivotal role of various inflammatory mechanisms in the progress of retinal degeneration. This review also offers an assessment of various therapeutic approaches, including gene-therapies and stem-cell-based therapies, for degenerative retinal diseases.
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Affiliation(s)
- Geetika Kaur
- Integrative Biosciences Center, Wayne State University, Detroit, MI 48202, USA;
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI 48202, USA
| | - Nikhlesh K. Singh
- Integrative Biosciences Center, Wayne State University, Detroit, MI 48202, USA;
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI 48202, USA
- Correspondence:
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13
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Li J, Chen YH, Li LZ, Wang F, Song W, Alolga RN, Zhou W, Yu H, Huang FQ, Yin X. Omics and Transgenic Analyses Reveal that Salvianolic Acid B Exhibits its Anti-Inflammatory Effects through Inhibiting the Mincle-Syk-Related Pathway in Macrophages. J Proteome Res 2021; 20:3734-3748. [PMID: 34080425 DOI: 10.1021/acs.jproteome.1c00325] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Salvianolic acid B (Sal B), the main water-soluble compound in Salvia miltiorrhiza, is known to exhibit anti-inflammatory activity, however, the underlying mechanism(s) is not completely uncovered. In this study, Sal B inhibited lipopolysaccharide (LPS)-induced M1 activation and promoted the transformation of macrophages from M1- to M2-type polarization. The altered lipid profiles of LPS-induced RAW 264.7 macrophages were partly restored by Sal B treatment. At the proteomic level, a total of 5612 proteins were identified and 432 were significantly changed in macrophages under LPS treatment. The differential proteins were classified into four clusters according to their expression level in blank, LPS, and Sal B groups. LPS-induced proteins in Cluster IV including Kif14, Mincle, and Sec62 were significantly recovered to almost normal levels by Sal B treatment. Use of knockdown Mincle or picetannol (inhibitor of Syk) led to significant reductions in the gene expressions of IL-1β, iNOS, and IL-12 and the release of NO. The converse was, however, observed for overexpressed Mincle. In addition, LPS- or trehalose-6,6-dibehenate-induced phosphorylation of Syk and PKCδ was decreased by Sal B treatment. These results suggest that Sal B inhibition of LPS-induced inflammation might be through inhibition of the Mincle-Syk-PKCδ signaling pathway.
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Affiliation(s)
- Jia Li
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Ya-Hui Chen
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Lan-Zhu Li
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China.,Beijing, State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Feizuo Wang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Wei Song
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Raphael N Alolga
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Wei Zhou
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Heming Yu
- Nanjing Hospital of Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu, China
| | - Feng-Qing Huang
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
| | - Xiaojian Yin
- State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 210009, Jiangsu, China
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Retinal Inflammation, Cell Death and Inherited Retinal Dystrophies. Int J Mol Sci 2021; 22:ijms22042096. [PMID: 33672611 PMCID: PMC7924201 DOI: 10.3390/ijms22042096] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/12/2021] [Accepted: 02/18/2021] [Indexed: 12/15/2022] Open
Abstract
Inherited retinal dystrophies (IRDs) are a group of retinal disorders that cause progressive and severe loss of vision because of retinal cell death, mainly photoreceptor cells. IRDs include retinitis pigmentosa (RP), the most common IRD. IRDs present a genetic and clinical heterogeneity that makes it difficult to achieve proper treatment. The progression of IRDs is influenced, among other factors, by the activation of the immune cells (microglia, macrophages, etc.) and the release of inflammatory molecules such as chemokines and cytokines. Upregulation of tumor necrosis factor alpha (TNFα), a pro-inflammatory cytokine, is found in IRDs. This cytokine may influence photoreceptor cell death. Different cell death mechanisms are proposed, including apoptosis, necroptosis, pyroptosis, autophagy, excessive activation of calpains, or parthanatos for photoreceptor cell death. Some of these cell death mechanisms are linked to TNFα upregulation and inflammation. Therapeutic approaches that reduce retinal inflammation have emerged as useful therapies for slowing down the progression of IRDs. We focused this review on the relationship between retinal inflammation and the different cell death mechanisms involved in RP. We also reviewed the main anti-inflammatory therapies for the treatment of IRDs.
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15
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Newton F, Megaw R. Mechanisms of Photoreceptor Death in Retinitis Pigmentosa. Genes (Basel) 2020; 11:genes11101120. [PMID: 32987769 PMCID: PMC7598671 DOI: 10.3390/genes11101120] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/15/2020] [Accepted: 09/22/2020] [Indexed: 02/08/2023] Open
Abstract
Retinitis pigmentosa (RP) is the most common cause of inherited blindness and is characterised by the progressive loss of retinal photoreceptors. However, RP is a highly heterogeneous disease and, while much progress has been made in developing gene replacement and gene editing treatments for RP, it is also necessary to develop treatments that are applicable to all causative mutations. Further understanding of the mechanisms leading to photoreceptor death is essential for the development of these treatments. Recent work has therefore focused on the role of apoptotic and non-apoptotic cell death pathways in RP and the various mechanisms that trigger these pathways in degenerating photoreceptors. In particular, several recent studies have begun to elucidate the role of microglia and innate immune response in the progression of RP. Here, we discuss some of the recent progress in understanding mechanisms of rod and cone photoreceptor death in RP and summarise recent clinical trials targeting these pathways.
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Affiliation(s)
- Fay Newton
- MRC Human Genetics Unit, University of Edinburgh, South Bridge, Edinburgh EH8 9YL, UK;
- Correspondence:
| | - Roly Megaw
- MRC Human Genetics Unit, University of Edinburgh, South Bridge, Edinburgh EH8 9YL, UK;
- Princess Alexandra Eye Pavilion, NHS Lothian, Edinburgh EH3 9HA, UK
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16
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Johansson K, Svensson LA, Mohlin C. Morphological analyzes of microglia heterogeneity and dynamics during photoreceptor degeneration in vitro: Presumptive dark microglia in porcine retina. Exp Eye Res 2020; 200:108217. [PMID: 32896534 DOI: 10.1016/j.exer.2020.108217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 08/31/2020] [Accepted: 09/01/2020] [Indexed: 11/18/2022]
Abstract
In the adult retina, ramifying microglia interact with the outer plexiform layer (OPL) monitoring the synaptic integrity between photoreceptors and post-synaptic target cells. Microglia are reactive during photoreceptor diseases, but their disease-related function(s) are not fully understood. Retinal explant cultures are model systems used to study degenerative events including photoreceptor degeneration and gliosis. Our culture paradigm, with adult porcine retinas subjected to coculture with human A-retinal pigment epithelia-19 (ARPE) cells, is an experimental approach resulting in improved photoreceptor survival and reduced gliosis. Under the in vitro pathological conditions with photoreceptor degeneration, reactive Iba1-and CD11b-immunoreactive microglia and their processes positioned in proximity with the OPL and among photoreceptor outer segments. Coculture for 3 days with ARPE-cells resulted in a significantly increased density of microglia at the OPL. After 5 days of culture, the density of microglia at the OPL was similar between coculture and control specimens. Electron microscopy revealed the presence of two subtypes of microglia: one exhibiting a dark nucleus and cytosol with dilated endoplasmic reticulum, vacuoles, endosomes and mitochondrial variations. This subtype localized close to synaptic structures in the OPL. The other subtype appeared as pale phagocytic microglia localized among degenerating outer segments. The Iba1-and CD11b-immunoreactive microglia in degenerating retina may be of two separate subtypes, which differ in localization, subcellular morphology and perhaps function.
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Affiliation(s)
| | | | - Camilla Mohlin
- Department of Chemistry and Biomedicine, Linnaeus University, Kalmar, Sweden
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17
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Tisi A, Passacantando M, Lozzi L, Maccarone R. Cerium oxide nanoparticles reduce the accumulation of autofluorescent deposits in light-induced retinal degeneration: Insights for age-related macular degeneration. Exp Eye Res 2020; 199:108169. [PMID: 32758489 DOI: 10.1016/j.exer.2020.108169] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 07/10/2020] [Accepted: 07/26/2020] [Indexed: 01/05/2023]
Abstract
Accumulation of lipofuscin deposits in the retinal pigment epithelium (RPE) is one of the main events involved in age-related macular degeneration and its increase together with RPE dysfunction, blood retinal barrier disruption and photoreceptors death progressively leads to blindness. Lipofuscin is the main autofluorescent (AF) component of the retina and therapies to counteract its deposition are a main goal to be achieved, since effective treatments have not yet been identified. Here, we first investigated the spatio-temporal pattern of AF deposits accumulation in the light-damage model of age-related macular degeneration. Afterward, we tested the ability of cerium oxide nanoparticles, a well known anti-oxidant agent, to counteract AF granules accumulation. The treatment was performed both before and after the induction of the degeneration. AF granules were quantified by confocal microscopy on whole mounted retinas. We demonstrated that the acute light-damage increases the accumulation of AF deposits in the hot spot retina in terms of number of granules and percentage of occupied area, with a peak 7 days after the exposure. Remarkably, cerium oxide nanoparticles showed a strong efficacy in preventing the formation of AF deposits when they were injected 3 days before light exposure. Moreover, when the treatment was performed 7 days after light exposure, nanoceria activity was found to be effective also in reducing the amount of the AF granules still deposited up to 60 days. These important results represent the very first evidence about the ability of cerium oxide nanoparticles to counteract AF deposits accumulation in retinal degeneration, laying the foundations for the development of a new therapy possibly targeting lipofuscin in AMD.
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Affiliation(s)
- A Tisi
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
| | - M Passacantando
- Department of Physical and Chemical Science, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy.
| | - L Lozzi
- Department of Physical and Chemical Science, University of L'Aquila, via Vetoio, Coppito 1, 67100, L'Aquila, Italy.
| | - R Maccarone
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
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18
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Tisi A, Parete G, Flati V, Maccarone R. Up-regulation of pro-angiogenic pathways and induction of neovascularization by an acute retinal light damage. Sci Rep 2020; 10:6376. [PMID: 32286488 PMCID: PMC7156521 DOI: 10.1038/s41598-020-63449-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 03/30/2020] [Indexed: 12/23/2022] Open
Abstract
The light damage (LD) model was mainly used to study some of the main aspects of age related macular degeneration (AMD), such as oxidative stress and photoreceptor death. Several protocols of light-induced retinal degeneration exist. Acute light damage is characterized by a brief exposure (24 hours) to high intensity light (1000 lux) and leads to focal degeneration of the retina which progresses over time. To date there are not experimental data that relate this model to neovascular events. Therefore, the purpose of this study was to characterize the retina after an acute light damage to assess whether the vascularization was affected. Functional, molecular and morphological investigations were carried out. The electroretinographic response was assessed at all recovery times (7, 60, 120 days after LD). Starting from 7 days after light damage there was a significant decrease in the functional response, which remained low up to 120 days of recovery. At 7 days after light exposure, neo-vessels invaded the photoreceptor layer and retinal neovascularization occurred. Remarkably, neoangiogenesis was associated to the up-regulation of VEGF, bFGF and their respective receptors (VEGFR2 and FGFR1) with the progression of degeneration. These important results indicate that a brief exposure to bright light induces the up-regulation of pro-angiogenic pathways with subsequent neovascularization.
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Affiliation(s)
- A Tisi
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy
| | - G Parete
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy
| | - V Flati
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy
| | - R Maccarone
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
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19
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Inhibition of LOX-1 prevents inflammation and photoreceptor cell death in retinal degeneration. Int Immunopharmacol 2020; 80:106190. [PMID: 31945611 DOI: 10.1016/j.intimp.2020.106190] [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: 11/12/2019] [Revised: 12/10/2019] [Accepted: 01/03/2020] [Indexed: 11/21/2022]
Abstract
PURPOSE To explore the expression and role of lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) in retinal degeneration. METHODS The retinal degeneration of BALB/c mice was induced by light exposure. BV2 cells were activated by LPS stimulation. Retinas or BV2 cells were pretreated with LOX-1 neutralizing antibody or Polyinosinic acid (PolyI) (the inhibitor of LOX-1) before light damage (LD) or LPS stimulation. LOX-1, TNF-α, IL-1β, CCL2 and NF-κB expression were detected in retinas or BV2 cells by real-time RT-PCR, western blot or ELISA. Histological analyses of retinas were performed. Photoreceptor cell death was assessed by TUNEL assay in retinas or by flow cytometry in 661W cells cultured in microglia-conditioned medium. RESULTS Photoreceptor cell death and elevated expression of LOX-1 were induced by LD in retinas of BALB/c mice. LOX-1 neutralizing antibody or PolyI pretreatment significantly reduced the elevated expression of LOX-1, TNF-α, IL-1β, CCL2 and p-NF-κB caused by LD in retinas. Inhibition of LOX-1 by LOX-1 neutralizing antibody or PolyI significantly reduced photoreceptor cell death induced by LD in retinas. Elevated levels of TNF-α, IL-1β and CCL2 caused by LPS were down-regulated by inhibition of LOX-1 in BV2 cells. Inhibition of LOX-1 reduces microglial neurotoxicity on photoreceptors. CONCLUSIONS LOX-1 expression is increased in light induced retinal degeneration, what's more, inhibition of LOX-1 prevents inflammation and photoreceptor cell death in retinal degeneration and reduces microglial neurotoxicity on photoreceptors. Therefore, LOX-1 can be used as a potential therapeutic target for such retinal degeneration diseases.
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20
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Tisi A, Passacantando M, Ciancaglini M, Maccarone R. Nanoceria neuroprotective effects in the light-damaged retina: A focus on retinal function and microglia activation. Exp Eye Res 2019; 188:107797. [PMID: 31520599 DOI: 10.1016/j.exer.2019.107797] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 09/10/2019] [Accepted: 09/10/2019] [Indexed: 11/18/2022]
Abstract
The use of nanomaterials is an emerging therapeutic approach for the treatment of several pathologies. Cerium oxide nanoparticles have been studied for biomedical application, including neurodegenerative disorders, such as age-related macular degeneration in several animal models. The light damage model is characterised by oxidative stress upregulation followed by photoreceptor death and microglia activation in the outer retina. For this reason, the light damage model mimics some aspects involved in human age-related macular degeneration pathogenesis. In this review, we focus on the neuroprotective effects on retinal function and microglia activation in the light damage model, considering the administration of the nanoparticles both before and after the injury. The electrical responses of the retina and the microglia number and morphology are clearly modulated by the treatment, supporting the beneficial effects of cerium oxide nanoparticles to counteract the degeneration processes in the retina.
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Affiliation(s)
- A Tisi
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
| | - M Passacantando
- Department of Physical and Chemical Science, University of L'Aquila, Via Vetoio, Coppito 1, 67100, L'Aquila, Italy.
| | - M Ciancaglini
- Department of Life, Health and Environmental Sciences, University of L'Aquila, Piazzale Salvatore Tommasi 1, Blocco 11, 67100, L'Aquila, Italy.
| | - R Maccarone
- Department of Biotechnology and Applied Clinical Sciences, University of L'Aquila, Via Vetoio, Coppito 2, 67100, L'Aquila, Italy.
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21
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Elbaz-Hayoun S, Rinsky B, Hagbi-Levi S, Grunin M, Chowers I. Evaluation of antioxidant treatments for the modulation of macrophage function in the context of retinal degeneration. Mol Vis 2019; 25:479-488. [PMID: 31588172 PMCID: PMC6776439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 09/03/2019] [Indexed: 11/24/2022] Open
Abstract
Purpose Oxidative stress and macrophages have been implicated in the pathogenesis of atrophic and neovascular age-related macular degeneration (aAMD and nvAMD). It is unclear whether oxidative injury mediates macrophage involvement in AMD. We aimed to investigate the effect of antioxidant treatments on human monocyte-derived macrophages (hMDMs) from patients with AMD in models for the disease. Methods Four antioxidant treatments were evaluated (G1: lutein + zeaxanthin, G2: lutein + zeaxanthin and zinc, G3: lutein + zeaxanthin, zinc, Lyc-O-Mato, and carnosic acid, G4: lutein + zeaxanthin, carnosic acid, and beta-carotene, G5: olive oil as vehicle control). The compounds were added to the culture medium of M1 (interferon-gamma [IFN-Ɣ] and lipopolysaccharide [LPS]) and M2a (interleukin-13 [IL-13] and IL-4) hMDMs from patients with AMD (n=7 and n=8, respectively). Mouse choroidal tissue was cultured with supernatants from treated M1/M2a hMDMs, to evaluate the effect of treatments on the angiogenic properties of macrophages with choroidal sprouting assay (CSA). Mouse retinal explants were cultured with treated hMDMs for 18 h, and evaluated for photoreceptor apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) labeling. Adult BALB/c mice (n=8) were exposed to 8,000 lux bright light for 3 h, and treated orally with antioxidant supplements for 7 days that preceded light injury and following it. Oxidative stress was assessed using an anti-4 hydroxynonenal (4-HNE) antibody. Retinal function and the thickness of the outer nuclear layer were evaluated with electroretinography (ERG) and histological analysis, respectively. Results The G3 treatment reduced M2a hMDMs-associated sprouting in the CSA compared to the untreated group (n=7, -1.52-fold, p=0.05). Conversely, the G2 treatment was associated with an increased neurotoxic effect of M2a hMDMs in the retinal explant assay compared to the control group (n=7, 1.37-fold, p=0.047), as well as compared to the G3 treatment group (1.46-fold, p=0.01). The G4 treatment was also associated with increased cytotoxicity compared to the control group (1.48-fold, p=0.004), and compared to the G3 treatment group (1.58-fold, p=0.001). In the in vivo light damage model, mice (n=8) supplemented with G2, G3, and G4 had decreased levels of oxidative injury assessed using 4-HNE labeling (-2.32-fold, -2.17-fold, and -2.18-fold, respectively, p<0.05 for all comparisons). None of the treatments were associated with reduced photoreceptor cell loss, as shown with histology and ERG. Conclusions Antioxidant treatment modulates M2a hMDMs at the functional level. In particular, we found that the G3 combination has a beneficial effect on M2a macrophages in reducing their angiogenic and neurotoxic capacity ex vivo. In addition, antioxidant treatments considerably reduced the oxidative stress level in light-damaged retinas. Further research is required to assess whether such therapies may curb macrophage-driven photoreceptor loss and neovascularization in AMD.
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Affiliation(s)
- Sarah Elbaz-Hayoun
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, and the Hebrew University - Hadassah School of Medicine
| | - Batya Rinsky
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, and the Hebrew University - Hadassah School of Medicine
| | - Shira Hagbi-Levi
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, and the Hebrew University - Hadassah School of Medicine
| | - Michelle Grunin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, and the Hebrew University - Hadassah School of Medicine
| | - Itay Chowers
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, and the Hebrew University - Hadassah School of Medicine
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Tsai T, Reinehr S, Maliha AM, Joachim SC. Immune Mediated Degeneration and Possible Protection in Glaucoma. Front Neurosci 2019; 13:931. [PMID: 31543759 PMCID: PMC6733056 DOI: 10.3389/fnins.2019.00931] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 08/19/2019] [Indexed: 12/13/2022] Open
Abstract
The underlying pathomechanisms for glaucoma, one of the most common causes of blindness worldwide, are still not identified. In addition to increased intraocular pressure (IOP), oxidative stress, excitotoxicity, and immunological processes seem to play a role. Several pharmacological or molecular/genetic methods are currently investigated as treatment options for this disease. Altered autoantibody levels were detected in serum, aqueous humor, and tissue sections of glaucoma patients. To further analyze the role of the immune system, an IOP-independent, experimental autoimmune glaucoma (EAG) animal model was developed. In this model, immunization with ocular antigens leads to antibody depositions, misdirected T-cells, retinal ganglion cell death and degeneration of the optic nerve, similar to glaucomatous degeneration in patients. Moreover, an activation of the complement system and microglia alterations were identified in the EAG as well as in ocular hypertension models. The inhibition of these factors can alleviate degeneration in glaucoma models with and without high IOP. Currently, several neuroprotective approaches are tested in distinct models. It is necessary to have systems that cover underlying pathomechanisms, but also allow for the screening of new drugs. In vitro models are commonly used, including single cell lines, mixed-cultures, and even organoids. In ex vivo organ cultures, pathomechanisms as well as therapeutics can be investigated in the whole retina. Furthermore, animal models reveal insights in the in vivo situation. With all these models, several possible new drugs and therapy strategies were tested in the last years. For example, hypothermia treatment, neurotrophic factors or the blockage of excitotoxity. However, further studies are required to reveal the pressure independent pathomechanisms behind glaucoma. There is still an open issue whether immune mechanisms directly or indirectly trigger cell death pathways. Hence, it might be an imbalance between protective and destructive immune mechanisms. Moreover, identified therapy options have to be evaluated in more detail, since deeper insights could lead to better treatment options for glaucoma patients.
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Affiliation(s)
| | | | | | - Stephanie C. Joachim
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
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23
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Xie J, Li Y, Dai J, He Y, Sun D, Dai C, Xu H, Yin ZQ. Olfactory Ensheathing Cells Grafted Into the Retina of RCS Rats Suppress Inflammation by Down-Regulating the JAK/STAT Pathway. Front Cell Neurosci 2019; 13:341. [PMID: 31402855 PMCID: PMC6670006 DOI: 10.3389/fncel.2019.00341] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/11/2019] [Indexed: 01/23/2023] Open
Abstract
The inflammatory microenvironment in the retina plays a vital role in the pathogenesis and progression of retinitis pigmentosa (RP). Microglial inflammatory cytokines production leads to gliosis and apoptosis of retinal neurons, and ultimately, visual loss. Cell-based therapies using grafted olfactory ensheathing cells (OECs) have demonstrated modulation of degenerative microenvironments in the central nervous system (CNS), in a number of animal models. However, mechanisms by which grafted OECs can reduce degeneration in the retina are not well understood. In the present study, we set up an in vitro OEC/BV2 microglia co-culture system, and an in vivo royal college of surgeons (RCS) rat model, used cell transplantation, immunohistochemistry, RT-PCR, western blot to explore the mechanisms by which OECs affect expression of pro- or anti-inflammatory cytokines and polarization of M(IL-6) and M(Arg1) type microglial activation in the retina. We found that compared with the LPS (Lipopolysaccharide) and olfactory nerve fibroblast (ONF), the OEC and BV2 co-culture group modulate microglial cytokines releasing toward the anti-inflammation, and away from the pro-inflammation, which was followed by higher IL-4 and IL-10 and lower TNF-a and IL-6 in their expression levels. In vivo, the transplantation group significantly reduced activated resident microglia/infiltrated macrophage, and expression of pro-inflammatory cytokines in RCS rats retina, increased anti-inflammatory cytokines in transplantation area. Additionally, we found that OECs expressed SOCS3 and down-regulated the JAK2/STAT3 (Janus Kinase 2/Signal Transducer and Activator of Transcription 3) pathway. Thirdly, OEC transplantation reduced Caspase-3 expression, protected inner retinal neurons and photoreceptors and therefore, delayed the visual function degeneration. In conclusion, our data suggest that OECs delay retinal degeneration in RP, at least in part through immunomodulation of microglia via the JAK/STAT pathway.
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Affiliation(s)
- Jing Xie
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yijian Li
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Jiaman Dai
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yan He
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Dayu Sun
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Chao Dai
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Haiwei Xu
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
| | - Zheng Qin Yin
- Southwest Eye Hospital, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China.,Key Laboratory of Visual Damage, Regeneration and Restoration of Chongqing, Chongqing, China
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Wooff Y, Man SM, Aggio-Bruce R, Natoli R, Fernando N. IL-1 Family Members Mediate Cell Death, Inflammation and Angiogenesis in Retinal Degenerative Diseases. Front Immunol 2019; 10:1618. [PMID: 31379825 PMCID: PMC6646526 DOI: 10.3389/fimmu.2019.01618] [Citation(s) in RCA: 142] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/28/2019] [Indexed: 12/22/2022] Open
Abstract
Inflammation underpins and contributes to the pathogenesis of many retinal degenerative diseases. The recruitment and activation of both resident microglia and recruited macrophages, as well as the production of cytokines, are key contributing factors for progressive cell death in these diseases. In particular, the interleukin 1 (IL-1) family consisting of both pro- and anti-inflammatory cytokines has been shown to be pivotal in the mediation of innate immunity and contribute directly to a number of retinal degenerations, including Age-Related Macular Degeneration (AMD), diabetic retinopathy, retinitis pigmentosa, glaucoma, and retinopathy of prematurity (ROP). In this review, we will discuss the role of IL-1 family members and inflammasome signaling in retinal degenerative diseases, piecing together their contribution to retinal disease pathology, and identifying areas of research expansion required to further elucidate their function in the retina.
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Affiliation(s)
- Yvette Wooff
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Si Ming Man
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Riemke Aggio-Bruce
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Nilisha Fernando
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
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Agrawal R, Balne PK, Wei X, Bijin VA, Lee B, Ghosh A, Narayanan R, Agrawal M, Connolly J. Cytokine Profiling in Patients With Exudative Age-Related Macular Degeneration and Polypoidal Choroidal Vasculopathy. Invest Ophthalmol Vis Sci 2019; 60:376-382. [PMID: 30682207 DOI: 10.1167/iovs.18-24387] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to investigate the cytokine profiles in plasma and aqueous humor of patients with choroidal neovascularization (CNV) due to exudative AMD and polypoidal choroidal vasculopathy (PCV). Methods In this cross-sectional study, 16 patients clinically diagnosed with AMD, 18 patients with PCV, and 50 age- and sex-matched cataract patients without AMD/PCV (controls) were enrolled. Study subjects were treatment naïve, and 200 μL undiluted aqueous humor and 5 mL peripheral venous blood were collected from the study subjects. Clinical samples were analyzed for 41 different cytokines by Luminex bead-based multiplex assay. Cytokines concentrations with detection rates of 50% or more were included for the analysis, and the differences in plasma and aqueous humor cytokines levels between each group were analyzed. Results The age of the patients with AMD and PCV was 70.62 ± 10.15 (mean ± SD) and 71.48 ± 9.08 years, respectively, and that in the control group was 62.8 ± 10.67 years. Aqueous humor cytokines growth-regulated oncogene (GRO), macrophage-derived chemokine (MDC), and macrophage inflammatory protein (MIP)-1α were significantly higher in AMD patients than controls (all P < 0.04), and GRO, MDC, MIP-1α, IL-8, IFN-γ-inducible protein 10, and monocyte chemotactic protein levels were significantly higher in PCV patients than controls (all P < 0.03). Soluble CD40 ligand and platelet-derived growth factor-AA levels were higher in plasma of healthy controls compared with AMD subjects. No significant differences in cytokine levels were observed between AMD and PCV patients for both plasma and aqueous humor. Conclusions In AMD and PCV patients, our data suggest that the pathologic changes are primarily driven by dysregulation of local immune factors in the eye, whereas the plasma cytokine levels are not elevated.
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Affiliation(s)
- Rupesh Agrawal
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore.,Singapore Eye Research Institute, Singapore
| | - Praveen Kumar Balne
- National Healthcare Group Eye Institute, Tan Tock Seng Hospital, Singapore.,Singapore Eye Research Institute, Singapore
| | - Xin Wei
- Khoo Teck Puat Hospital, Department of Ophthalmology and Visual Sciences, Singapore
| | | | | | - Arkasubhra Ghosh
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bangalore, India
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Evidences Suggesting that Distinct Immunological and Cellular Responses to Light Damage Distinguishes Juvenile and Adult Rat Retinas. Int J Mol Sci 2019; 20:ijms20112744. [PMID: 31167447 PMCID: PMC6600267 DOI: 10.3390/ijms20112744] [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: 03/29/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 11/29/2022] Open
Abstract
To unravel the mechanisms behind the higher resistance to light damage of juvenile (JR) versus adult (AR) rats, Sprague Dawley rats were exposed to a bright luminous environment of 10, 000 lux. The light-induced retinopathy (LIR) was assessed with histology, electroretinography and immunohistochemistry (IHC). In JR, 2 days of exposure induced the typical LIR, while >3 days added little LIR. IHC revealed a subtle migration of microglia (Iba1 marker) from the inner to the outer retina after 3 days of exposure in JR contrasting with the stronger reaction seen after 1 day in AR. Similarly, in JR, the Müller cells expressed less intense GFAP, CNTF and FGF2 staining compared to AR. Our results suggest that in JR the degree of retinal damage is not proportional to the duration of light exposure (i.e., dose-independent retinopathy), contrasting with the dose-dependent LIR reported in AR. The immature immune system in JR may explain the delayed and/or weaker inflammatory response compared to AR, a finding that would also point to the devastating contribution of the immune system in generating the LIR phenotype, a claim also advanced to explain the pathophysiology of other retinal degenerative disorders such as Age-related Macular Degeneration, Diabetic Retinopathy and Retinitis Pigmentosa.
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Lactobacillus paracasei KW3110 Prevents Blue Light-Induced Inflammation and Degeneration in the Retina. Nutrients 2018; 10:nu10121991. [PMID: 30558320 PMCID: PMC6316514 DOI: 10.3390/nu10121991] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/11/2018] [Accepted: 12/13/2018] [Indexed: 12/18/2022] Open
Abstract
Age-related macular degeneration and retinitis pigmentosa are leading causes of blindness and share a pathological feature, which is photoreceptor degeneration. To date, the lack of a potential treatment to prevent such diseases has raised great concern. Photoreceptor degeneration can be accelerated by excessive light exposure via an inflammatory response; therefore, anti-inflammatory agents would be candidates to prevent the progress of photoreceptor degeneration. We previously reported that a lactic acid bacterium, Lactobacillus paracasei KW3110 (L. paracasei KW3110), activated macrophages suppressing inflammation in mice and humans. Recently, we also showed that intake of L. paracasei KW3110 could mitigate visual display terminal (VDT) load-induced ocular disorders in humans. However, the biological mechanism of L. paracasei KW3110 to retain visual function remains unclear. In this study, we found that L. paracasei KW3110 activated M2 macrophages inducing anti-inflammatory cytokine interleukin-10 (IL-10) production in vitro using bone marrow-derived M2 macrophages. We also show that IL-10 gene expression was significantly increased in the intestinal immune tissues 6 h after oral administration of L. paracasei KW3110 in vivo. Furthermore, we demonstrated that intake of L. paracasei KW3110 suppressed inflammation and photoreceptor degeneration in a murine model of light-induced retinopathy. These results suggest that L. paracasei KW3110 may have a preventive effect against degrative retinal diseases.
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Kreisel T, Wolf B, Keshet E, Licht T. Unique role for dentate gyrus microglia in neuroblast survival and in VEGF-induced activation. Glia 2018; 67:594-618. [DOI: 10.1002/glia.23505] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 06/24/2018] [Accepted: 06/25/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Tirzah Kreisel
- Department of Developmental Biology and Cancer Research; Hadassah Medical School, The Hebrew University; Jerusalem Israel
- Edmond and Lily Safra Center for Brain Sciences (ELSC); The Hebrew University; Jerusalem Israel
| | - Brachi Wolf
- Department of Developmental Biology and Cancer Research; Hadassah Medical School, The Hebrew University; Jerusalem Israel
| | - Eli Keshet
- Department of Developmental Biology and Cancer Research; Hadassah Medical School, The Hebrew University; Jerusalem Israel
| | - Tamar Licht
- Department of Developmental Biology and Cancer Research; Hadassah Medical School, The Hebrew University; Jerusalem Israel
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Efremov YR, Proskurina AS, Potter EA, Dolgova EV, Efremova OV, Taranov OS, Ostanin AA, Chernykh ER, Kolchanov NA, Bogachev SS. Cancer Stem Cells: Emergent Nature of Tumor Emergency. Front Genet 2018; 9:544. [PMID: 30505319 PMCID: PMC6250818 DOI: 10.3389/fgene.2018.00544] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/26/2018] [Indexed: 12/12/2022] Open
Abstract
A functional analysis of 167 genes overexpressed in Krebs-2 tumor initiating cells was performed. In the first part of the study, the genes were analyzed for their belonging to one or more of the three groups, which represent the three major phenotypic manifestation of malignancy of cancer cells, namely (1) proliferative self-sufficiency, (2) invasive growth and metastasis, and (3) multiple drug resistance. 96 genes out of 167 were identified as possible contributors to at least one of these fundamental properties. It was also found that substantial part of these genes are also known as genes responsible for formation and/or maintenance of the stemness of normal pluri-/multipotent stem cells. These results suggest that the malignancy is simply the ability to maintain the stem cell specific genes expression profile, and, as a consequence, the stemness itself regardless of the controlling effect of stem niches. In the second part of the study, three stress factors combined into the single concept of "generalized cellular stress," which are assumed to activate the expression of these genes, were defined. In addition, possible mechanisms for such activation were identified. The data obtained suggest the existence of a mechanism for the de novo formation of a pluripotent/stem phenotype in the subpopulation of "committed" tumor cells.
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Affiliation(s)
- Yaroslav R Efremov
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Anastasia S Proskurina
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Ekaterina A Potter
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Evgenia V Dolgova
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Oksana V Efremova
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Oleg S Taranov
- The State Research Center of Virology and Biotechnology Vector, Koltsovo, Russia
| | - Aleksandr A Ostanin
- Research Institute of Fundamental and Clinical Immunology, Novosibirsk, Russia
| | - Elena R Chernykh
- Research Institute of Fundamental and Clinical Immunology, Novosibirsk, Russia
| | - Nikolay A Kolchanov
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Sergey S Bogachev
- Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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30
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Morita Y, Jounai K, Miyake M, Inaba M, Kanauchi O. Effect of Heat-Killed Lactobacillus paracasei KW3110 Ingestion on Ocular Disorders Caused by Visual Display Terminal (VDT) Loads: A Randomized, Double-Blind, Placebo-Controlled Parallel-Group Study. Nutrients 2018; 10:nu10081058. [PMID: 30096952 PMCID: PMC6116181 DOI: 10.3390/nu10081058] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/30/2018] [Accepted: 08/07/2018] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Visual display terminals (VDTs) emitting blue light can cause ocular disorders including eye fatigue. Some dietary constituents have been reported to be effective in improving ocular disorders while few clinical studies have been performed. We evaluated the effects of heat-killed Lactobacillus paracasei KW 3110 on improving ocular disorders and symptoms of eye fatigue among healthy human subjects with VDT loads. METHODS In vitro, the effect of L. paracasei KW3110 on blue light-induced human retinal pigment epithelial (ARPE-19) cell damage. For clinical studies, 62 healthy Japanese volunteers of 35 to 45 years of age who had experienced eye fatigue were randomized into two groups and given a placebo or L. paracasei KW3110-containing supplements for eight weeks. The primary endpoint was changes in VDT load-induced eye fatigue as determined by critical flicker frequency four and eight weeks after the start of supplementation. RESULTS In vitro, blue light-induced human retinal cell death was suppressed with the culture supernatants of cells treated with L. paracasei KW3110. In clinical study, the VDT load-induced reduction of critical flicker frequency tended to be milder in the L. paracasei KW3110 group when compared with the placebo group during the fourth week. Subgroup analysis classified by the degree of eye fatigue showed that the VDT load-induced reduction of critical flicker frequency was significantly better in the high-level eye fatigue subjects from the L. paracasei KW3110 group when compared with the placebo group during the fourth week (p = 0.020). CONCLUSIONS L. paracasei KW3110 suppressed blue light-induced retinal pigment epithelial cell death. In the clinical study, ingestion of L. paracasei KW3110 had a potential to improve eye fatigue induced by VDT loads especially high levels of eye fatigue. However, further studies should be required to show more dependable clinical efficacy of L. paracasei KW3110.
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Affiliation(s)
- Yuji Morita
- Research Laboratories for Health Science & Food Technologies, Kirin Company, Ltd., 1-13-5 Fukuura Kanazawa-ku, Yokohama-shi, Kanagawa 236-0004, Japan.
| | - Kenta Jounai
- Technical Development Center, Koiwai Dairy Products Co. Ltd., Sayama, Saitama 350-1321, Japan.
| | - Mika Miyake
- Research Laboratories for Health Science & Food Technologies, Kirin Company, Ltd., 1-13-5 Fukuura Kanazawa-ku, Yokohama-shi, Kanagawa 236-0004, Japan.
| | | | - Osamu Kanauchi
- Research Laboratories for Health Science & Food Technologies, Kirin Company, Ltd., 1-13-5 Fukuura Kanazawa-ku, Yokohama-shi, Kanagawa 236-0004, Japan.
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Nakamura M, Yako T, Kuse Y, Inoue Y, Nishinaka A, Nakamura S, Shimazawa M, Hara H. Exposure to excessive blue LED light damages retinal pigment epithelium and photoreceptors of pigmented mice. Exp Eye Res 2018; 177:1-11. [PMID: 30040948 DOI: 10.1016/j.exer.2018.07.022] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/11/2018] [Accepted: 07/20/2018] [Indexed: 12/26/2022]
Abstract
To determine the characteristics of the damages of the retinal pigment epithelium (RPE) and photoreceptors of pigmented mice induced by exposure to blue light emitting diode (LED) light, and to determine the mechanisms causing the damages. Exposure to blue LED light for 3 days induced retinal damage, and the characteristics of the damage differed from that induced by white fluorescent light exposure. Ophthalmoscopy showed that blue LED exposure for 3 days induced white spots on the retina, and histological examinations showed materials accumulated at the IS/OS junction of the photoreceptors. The accumulated materials were stained by ionized calcium binding adapter molecule-1 (Iba-1), a marker for macrophages. The debris was also positive for periodic acid-Schiff (PAS). An enlarging the area of RPE was detected just after the blue LED exposure especially around the optic nerve, and this led to a secondary degeneration of the photoreceptors. Exposure of pigmented mice to 3 consecutive days of blue LED light will cause RPE and photoreceptor damage. The damage led to an accumulation of macrophages and drusen-like materials around the outer segments of the photoreceptors. This blue light exposed model may be useful for investigating the pathogenesis of non-exudative age-related macular degeneration.
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Affiliation(s)
- Maho Nakamura
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Tomohiro Yako
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Yoshiki Kuse
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Yuki Inoue
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Anri Nishinaka
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Shinsuke Nakamura
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan
| | - Masamitsu Shimazawa
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan.
| | - Hideaki Hara
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, Gifu, Japan.
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S100B immunization triggers NFκB and complement activation in an autoimmune glaucoma model. Sci Rep 2018; 8:9821. [PMID: 29959432 PMCID: PMC6026137 DOI: 10.1038/s41598-018-28183-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 06/13/2018] [Indexed: 12/27/2022] Open
Abstract
In glaucoma, latest studies revealed an involvement of the complement system with and without an elevated intraocular pressure. In the experimental autoimmune glaucoma model, immunization with antigens, such as S100B, lead to retinal ganglion cell (RGC) loss and optic nerve degeneration after 28 days. Here, we investigated the timeline of progression of the complement system, toll-like-receptor 4 (TLR4), and the transcription factor nucleus factor-kappa B (NFκB). Therefore, rats were immunized with S100B protein (S100) and analyzed at 3, 7, and 14 days. RGC numbers were comparable at all points in time, whereas a destruction of S100 optic nerves was noted at 14 days. A significant increase of mannose binding lectin (MBL) was observed in S100 retinas at 3 days. Subsequently, significantly more MBL+ cells were seen in S100 optic nerves at 7 and 14 days. Accordingly, C3 was upregulated in S100 retinas at 14 days. An increase of interleukin-1 beta was noted in S100 aqueous humor samples at 7 days. In this study, activation of complement system via the lectin pathway was obvious. However, no TLR4 alterations were noted in S100 retinas and optic nerves. Interestingly, a significant NFκB increase was observed in S100 retinas at 7 and 14 days. We assume that NFκB activation might be triggered via MBL leading to glaucomatous damage.
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The Role of Microglia in Diabetic Retinopathy: Inflammation, Microvasculature Defects and Neurodegeneration. Int J Mol Sci 2018; 19:ijms19010110. [PMID: 29301251 PMCID: PMC5796059 DOI: 10.3390/ijms19010110] [Citation(s) in RCA: 233] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 12/23/2017] [Accepted: 12/25/2017] [Indexed: 12/15/2022] Open
Abstract
Diabetic retinopathy is a common complication of diabetes mellitus, which appears in one third of all diabetic patients and is a prominent cause of vision loss. First discovered as a microvascular disease, intensive research in the field identified inflammation and neurodegeneration to be part of diabetic retinopathy. Microglia, the resident monocytes of the retina, are activated due to a complex interplay between the different cell types of the retina and diverse pathological pathways. The trigger for developing diabetic retinopathy is diabetes-induced hyperglycemia, accompanied by leukostasis and vascular leakages. Transcriptional changes in activated microglia, mediated via the nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) and extracellular signal–regulated kinase (ERK) signaling pathways, results in release of various pro-inflammatory mediators, including cytokines, chemokines, caspases and glutamate. Activated microglia additionally increased proliferation and migration. Among other consequences, these changes in microglia severely affected retinal neurons, causing increased apoptosis and subsequent thinning of the nerve fiber layer, resulting in visual loss. New potential therapeutics need to interfere with these diabetic complications even before changes in the retina are diagnosed, to prevent neuronal apoptosis and blindness in patients.
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Rinsky B, Hagbi-Levi S, Elbaz-Hayoun S, Grunin M, Chowers I. Characterizing the effect of supplements on the phenotype of cultured macrophages from patients with age-related macular degeneration. Mol Vis 2017; 23:889-899. [PMID: 29259394 PMCID: PMC5723149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 12/04/2017] [Indexed: 11/07/2022] Open
Abstract
Purpose Oral vitamin and mineral supplements reduce the risk of visual loss in age-related macular degeneration (AMD). However, the pathways that mediate this beneficial effect are poorly understood. Macrophages may exert oxidative, inflammatory, and angiogenic effects in the context of AMD. We aim to assess if oral supplements can modulate the macrophage phenotype in this disease. Methods Monocytes were isolated from patients with neovascular AMD (nvAMD), cultured, matured to macrophages, and polarized to classical [M1 (stimulated by IFNγ and lipopolysaccharide (LPS))] and alternative [M2 (stimulated with IL-4 and IL-13)] phenotypes. Combinations of antioxidants including lutein+zeaxanthin (1 μM; 0.2 μM), zinc (10 µM), carnosic acid (2 µM), beta-carotene (2 µM), and standardized tomato extract containing lycopene and other tomato phytonutrients were added to the culture media. Levels of anti-inflammatory, antioxidant, and pro-angiogenic gene and protein expression were then evaluated. Results Combinations of lutein and carnosic acid with zinc and standardized tomato extract or with beta-carotene yielded an antioxidative, anti-inflammatory, and antiangiogenic effect in M1 and M2 macrophages. These effects manifested in the upregulation of antioxidative genes (HMOX1, SOD1) and the downregulation of pro-angiogenic genes and pro-inflammatory genes (SDF-1, TNF-alpha, IL-6, MCP-1). Lutein monotherapy or a combination of lutein and zinc had less effect on the expression of these genes. Conclusions Combinations of supplements can modify the expression of genes and proteins that may be relevant for the involvement of macrophages in the pathogenesis of AMD. Further studies are required to evaluate if the modulation of the macrophage phenotype partially accounts for the beneficial effect of oral supplements in AMD and if modification of the AREDS formula can improve its effect on macrophages.
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Schäfer N, Grosche A, Schmitt SI, Braunger BM, Pauly D. Complement Components Showed a Time-Dependent Local Expression Pattern in Constant and Acute White Light-Induced Photoreceptor Damage. Front Mol Neurosci 2017; 10:197. [PMID: 28676742 PMCID: PMC5476694 DOI: 10.3389/fnmol.2017.00197] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/02/2017] [Indexed: 11/26/2022] Open
Abstract
Background: Photoreceptor cell death due to extensive light exposure and induced oxidative-stress are associated with retinal degeneration. A correlated dysregulation of the complement system amplifies the damaging effects, but the local and time-dependent progression of this mechanism is not thoroughly understood. Methods: Light-induced photoreceptor damage (LD) was induced in Balb/c mice with white light illumination either for 24 h with 1000 lux (constant model) or 0.5 h with 5000 lux (acute model). Complement protein and mRNA expression levels were compared at 1 and 3 days post-LD for C1s, complement factor B (CFB), mannose binding lectin A, mannose-binding protein-associated serine protease 1 (MASP-1), C3, C4, C9, and complement factor P in retina and RPE/choroid. Histological analyses visualized apoptosis, microglia/macrophage migration, gliosis and deposition of the complement activation marker C3d. Systemic anaphylatoxin serum concentrations were determined using an ELISA. Results: Apoptosis, gliosis and microglia/macrophage migration into the outer nuclear layer showed similar patterns in both models. Local complement factor expression revealed an early upregulation of complement factor mRNA in the acute and constant light regimen at 1 day post-treatment for c1s, cfb, masp-1, c3, c4 and c9 in the RPE/choroid. However, intraretinal complement mRNA expression for c1s, cfb, c3 and c4 was increased at 1 day in the constant and at 3 days in the acute model. A corresponding regulation on protein level in the retina following both LD models was observed for C3, which was upregulated at 1 day and correlated with increased C3d staining in the ganglion cell layer and at the RPE. In the RPE/choroid C1s-complex protein detection was increased at 3 days after LD irrespectively of the light intensities used. Conclusion: LD in mouse eyes is correlated with local complement activity. The time-dependent local progression of complement regulation on mRNA and protein levels were equivalent in the acute and constant LD model, except for the intraretinal, time-dependent mRNA expression. Knowing the relative time courses of local complement expression and cellular activity can help to elucidate novel therapeutic options in retinal degeneration indicating at which time point of disease complement has to be rebalanced.
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Affiliation(s)
- Nicole Schäfer
- Department of Ophthalmology, University Hospital RegensburgRegensburg, Germany
| | - Antje Grosche
- Institute of Human Genetics, University RegensburgRegensburg, Germany
| | - Sabrina I Schmitt
- Institute of Human Anatomy and Embryology, University RegensburgRegensburg, Germany
| | - Barbara M Braunger
- Institute of Human Anatomy and Embryology, University RegensburgRegensburg, Germany
| | - Diana Pauly
- Department of Ophthalmology, University Hospital RegensburgRegensburg, Germany
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Arroba AI, Valverde ÁM. Modulation of microglia in the retina: new insights into diabetic retinopathy. Acta Diabetol 2017; 54:527-533. [PMID: 28349217 DOI: 10.1007/s00592-017-0984-z] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/12/2017] [Indexed: 01/07/2023]
Abstract
During last decades, the diagnosis of diabetes has been associated with several chronic complications such as diabetic retinopathy (DR). Recent studies of DR have revealed an inflammatory component, which precedes the detection of alterations in the visual function. During DR, the inflammatory process presents two opposite roles depending on the polarization of resident immune cells of the retina triggering proinflammatory (M1) or antiinflammatory (M2) actions. In an early stage of DR, the M2 response concurs with the M1 and is able to ameliorate inflammation and delay the progression of the disease. However, during the progression of DR, the M1 response is maintained whereas the M2 declines and, in this scenario, the classical proinflammatory signaling pathways are chronically activated leading to retinal neurodegeneration and the loss of visual function. The M1/M2 responses are closely related to the activation and polarization of microglial cells. This review aims to offer an overview of the recent insights into the role of microglial cells during inflammation in DR. We have focused on the possibility of modulating microglia polarization as a new therapeutic strategy in DR treatments.
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Affiliation(s)
- Ana I Arroba
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain.
- Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERdem), ISCIII, 28029, Madrid, Spain.
| | - Ángela M Valverde
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain.
- Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERdem), ISCIII, 28029, Madrid, Spain.
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Natoli R, Fernando N, Madigan M, Chu-Tan JA, Valter K, Provis J, Rutar M. Microglia-derived IL-1β promotes chemokine expression by Müller cells and RPE in focal retinal degeneration. Mol Neurodegener 2017; 12:31. [PMID: 28438165 PMCID: PMC5404662 DOI: 10.1186/s13024-017-0175-y] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 04/14/2017] [Indexed: 01/10/2023] Open
Abstract
Background Chemokine signalling is required for the homing of leukocytes during retinal inflammation, and is associated with pathogenesis of diseases such as age-related macular degeneration (AMD). Here, we explore the role of interleukin-1β (IL-1β) in modulating AMD-associated chemokines Ccl2, Cxcl1, and Cxcl10 during photo-oxidative retinal damage, and the effect on both the accumulation of outer-retinal macrophages, and death of photoreceptors. Methods Inhibition of retinal IL-1β expression was performed using either siRNA or antibody neutralisation, which was intravitreally injected in SD rats prior to photo-oxidative damage. Changes in the expression and localisation of Il-1β, Ccl2, Cxcl1 and Cxcl10 genes were assessed using qPCR and in situ hybridisation, while the recruitment of retinal macrophages was detected using immunohistochemistry for IBA1. Levels of photoreceptor cell death were determined using TUNEL. Results Photo-oxidative damage elevated the expression of Il-1β and inflammasome-related genes, and IL-1β protein was detected in microglia infiltrating the outer retina. This was associated with increased expression of Ccl2, Cxcl1, and Cxcl10. Intravitreal IL-1β inhibitors suppressed chemokine expression following damage and reduced macrophage accumulation and photoreceptor death. Moreover, in Müller and RPE cell cultures, and in vivo, Ccl2, Cxcl1 and Cxcl10 were variously upregulated when stimulated with IL-1β, with increased macrophage accumulation detected in vivo. Conclusions IL-1β is produced by retinal microglia and macrophages and promotes chemokine expression by Müller cells and RPE in retinal degeneration. Targeting IL-1β may prove efficacious in broadly suppressing chemokine-mediated inflammation in retinal dystrophies such as AMD.
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Affiliation(s)
- Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Nilisha Fernando
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Michele Madigan
- Save Sight Institute, Discipline of Clinical Ophthalmology, The University of Sydney, Sydney, NSW, Australia.,School of Optometry and Vision Science, The University of New South Wales, Kensington, NSW, Australia
| | - Joshua A Chu-Tan
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Krisztina Valter
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,ANU Medical School, The Australian National University, Canberra, ACT, Australia
| | - Jan Provis
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia. .,ANU Medical School, The Australian National University, Canberra, ACT, Australia.
| | - Matt Rutar
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.,The University of Melbourne, Parkville, VIC, Australia
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Fernando N, Natoli R, Valter K, Provis J, Rutar M. The broad-spectrum chemokine inhibitor NR58-3.14.3 modulates macrophage-mediated inflammation in the diseased retina. J Neuroinflammation 2016; 13:47. [PMID: 26911327 PMCID: PMC4765229 DOI: 10.1186/s12974-016-0514-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 02/18/2016] [Indexed: 12/20/2022] Open
Abstract
Background The activity of macrophages is implicated in the progression of retinal pathologies such as atrophic age-related macular degeneration (AMD), where they accumulate among the photoreceptor layer and subretinal space. This process is aided by the local expression of chemokines, which furnish these cells with directional cues that augment their migration to areas of retinal injury. While these qualities make chemokines a potential therapeutic target in curtailing damaging retinal inflammation, their wide variety and signalling redundancy pose challenges in broadly modulating their activity. Here, we examine the efficacy of the broad-spectrum chemokine inhibitor NR58-3.14.3—a suppressor of Ccl- and Cxcl- chemokine pathways—in suppressing macrophage activity and photoreceptor death, using a light-induced model of outer retinal atrophy and inflammation. Methods Photo-oxidative damage was induced in SD rats via exposure to 1000 lux of light for 24 h, after which animals were euthanized at 0- or 7-day post-exposure time points. Prior to damage, NR58-3.14.3 was injected intravitreally. Retinas were harvested and evaluated for the effect of NR58-3.14.3 on subretinal macrophage accumulation and cytokine expression profile, as well as photoreceptor degeneration. Results We report that intravitreal administration of NR58-3.14.3 reduces the accumulation of macrophages in the outer retina following exposure to light damage, at both 0- and 7-day post-exposure time points. Injection of NR58-3.14.3 also reduced the up-regulation of inflammatory markers including of Il6, Ccl3, and Ccl4 in infiltrating macrophages, which are promoters of their pathogenic activity in the retina. Finally, NR58-3.14.3-injected retinas displayed markedly reduced photoreceptor death following light damage, at both 0 and 7 days post-exposure. Conclusions Our findings indicate that NR58-3.14.3 is effective in inhibiting subretinal macrophage accumulation in light-induced retinal degeneration and illustrate the potential of broad-spectrum chemokine inhibitors as novel therapeutic agents in thwarting retinal inflammation. Although broad-spectrum chemokine inhibitors may not be appropriate for all retinal inflammatory conditions, our results suggest that they may be beneficial for retinal dystrophies in which chemokine expression and subretinal macrophage accumulation are implicated, such as advanced AMD.
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Affiliation(s)
- Nilisha Fernando
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT, 2601, Australia
| | - Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT, 2601, Australia.,ANU Medical School, The Australian National University, Canberra, Australia
| | - Krisztina Valter
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT, 2601, Australia.,ANU Medical School, The Australian National University, Canberra, Australia
| | - Jan Provis
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT, 2601, Australia.,ANU Medical School, The Australian National University, Canberra, Australia
| | - Matt Rutar
- The John Curtin School of Medical Research, The Australian National University, Building 131, Garran Rd, Canberra, ACT, 2601, Australia.
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