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Salas A, Badia A, Fontrodona L, Zapata M, García-Arumí J, Duarri A. Neovascular Progression and Retinal Dysfunction in the Laser-Induced Choroidal Neovascularization Mouse Model. Biomedicines 2023; 11:2445. [PMID: 37760886 PMCID: PMC10525599 DOI: 10.3390/biomedicines11092445] [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: 07/28/2023] [Revised: 08/22/2023] [Accepted: 08/29/2023] [Indexed: 09/29/2023] Open
Abstract
The mouse model of laser-induced choroidal neovascularization (LI-CNV) has been widely used to study neovascular age-related macular degeneration; however, it still lacks a comprehensive characterization. Here, CNV was induced in the eyes of 12-week-old C57BL/6J male mice by argon laser irradiation. We studied the CNV lesion progression of an LI-CNV mouse cohort by using multimodal imaging (color fundus, optical coherence tomography (OCT), and fluorescence angiography, focal electroretinography features for 14 days, and related cytokines, angiogenic factors, and reactive gliosis for 5 days. CNV lesions involving the rupture of the Bruch's membrane were confirmed using funduscopy and OCT after laser photocoagulation. During the initial stage, from the CNV induction until day 7, CNV lesions presented leakage observed by using fluorescence angiography and a typical hyperreflective area with cell infiltration, subretinal leakage, and degeneration of photoreceptors observed through OCT. This correlated with decreased retinal responses to light. Moreover, inflammatory and angiogenic markers were reduced to basal levels in the first 5 days of CNV progression. In contrast, reactive gliosis and the VEGF expression in retinal sections were sustained, with infiltration of endothelial cells in the subretinal space. In the second stage, between days 7 and 14 post-induction, we observed stabilization of the CNV lesions, a hyperfluorescent area corresponding to the formation of fibrosis, and a partial rescue of retinal function. These findings suggest that the LI-CNV lesion development goes through an acute phase during the first seven days following induction, and then the CNV lesion stabilizes. According to these results, this model is suitable for screening anti-inflammatory and anti-angiogenic drugs in the early stages of LI-CNV. At the same time, it is more convenient for screening anti-fibrotic compounds in the later stages.
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Affiliation(s)
- Anna Salas
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
| | - Anna Badia
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
| | - Laura Fontrodona
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
| | - Miguel Zapata
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
- Department of Ophthalmology, Vall d’Hebron Hospital Universitari, 08035 Barcelona, Spain
| | - José García-Arumí
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
- Department of Ophthalmology, Vall d’Hebron Hospital Universitari, 08035 Barcelona, Spain
| | - Anna Duarri
- Ophthalmology Research Group, Vall d’Hebron Institut de Recerca, 08035 Barcelona, Spain
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Li C, Sun J, Zhang X, Zhou M, Gan X. Implications of MCU complex in metabolic diseases. FASEB J 2023; 37:e23046. [PMID: 37389546 DOI: 10.1096/fj.202300218r] [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: 02/07/2023] [Revised: 05/17/2023] [Accepted: 06/07/2023] [Indexed: 07/01/2023]
Abstract
Metabolic diseases are considered the primary culprit for physical and mental health of individuals. Although the diagnosis of these diseases is relatively easy, more effective and convenient potent drugs are still being explored. Ca2+ across the inner mitochondrial membrane is a vital intracellular messenger that regulates energy metabolism and cellular Ca2+ homeostasis and is involved in cell death. Mitochondria rely on a selective mitochondrial Ca2+ unidirectional transport complex (MCU complex) in their inner membrane for Ca2+ uptake. We found that the channel contains several subunits and undergoes dramatic transformations in various pathological processes, especially in metabolic diseases. In this way, we believe that the MCU complex becomes a target with significant potential for these diseases. However, there is no review linking the two factors, thus hindering the possibility of new drug production. Here, we highlight the connection between MCU complex-related Ca2+ transport and the pathophysiology of metabolic diseases, adding understanding and insight at the molecular level to provide new insights for targeting MCU to reverse metabolism-related diseases.
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Affiliation(s)
- Chen Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Jiyu Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xidan Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Min Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xueqi Gan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
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He W, Wu F, Xiong H, Zeng J, Gao Y, Cai Z, Pang J, Zheng Y. Promoting TFEB nuclear localization with curcumin analog C1 attenuates sensory hair cell injury and delays age-related hearing loss in C57BL/6 mice. Neurotoxicology 2023; 95:218-231. [PMID: 36792013 DOI: 10.1016/j.neuro.2023.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/16/2023] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
Sensory hair cell (HC) injuries, especially outer hair cell (OHC) loss, are well-documented to be the primary pathology of age-related hearing loss (AHL). Recent studies have demonstrated that autophagy plays an important role in HC injury in the inner ear. In our previous works, a decline in autophagy levels and HC loss were found to occur simultaneously in the inner ears of aged C57BL/6 mice, and the administration of rapamycin promoted autophagy levels, which reduced OHC loss and delayed AHL, but the underlying mechanism of autophagy in AHL has not been well elucidated. Transcription factor EB (TFEB), an autophagy regulator and the downstream target of mammalian target of rapamycin (mTOR), is involved in the pathological development of neurodegenerative disease. This study would address the link between autophagy and TFEB in aged C57BL/6 mouse cochleae and clarify the effect of the TFEB activator curcumin analog C1 (C1) in aged cochleae. Decreased TFEB nuclear localization (p = 0.0371) and autophagy dysfunction (p = 0.0273) were observed in the cochleae of aged C57BL/6 mice that exhibited AHL, HCs loss and HCs senescence. Treatment with C1 promoted TFEB nuclear localization and restored autophagy, subsequently alleviating HC injury and delaying AHL. The protective effect of C1 on HEI-OC1 cells against autophagy disorder and aging induced by D-galactose was abolished by chloroquine, which is one of the commonly used autophagy inhibitors. Overall, our results demonstrated that the capacity to perform autophagy is mediated by the nuclear localization of TFEB in aged C57BL/6 mouse cochleae. C1 promotes the nuclear localization of TFEB, subsequently alleviating HC injury and delaying AHL by restoring the impaired autophagy function. TFEB may serve as a new therapeutic target for AHL treatment.
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Affiliation(s)
- Wuhui He
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Fan Wu
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hao Xiong
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China
| | - Junbo Zeng
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China
| | - Yiming Gao
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Ziyi Cai
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jiaqi Pang
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
| | - Yiqing Zheng
- Department of Otolaryngology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China; Institute of Hearing and Speech-Language Science, Sun Yat-sen University, Guangzhou, China.
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Retinal Ganglion Cells: Global Number, Density and Vulnerability to Glaucomatous Injury in Common Laboratory Mice. Cells 2022; 11:cells11172689. [PMID: 36078097 PMCID: PMC9454702 DOI: 10.3390/cells11172689] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 11/30/2022] Open
Abstract
How many RBPMS+ retinal ganglion cells (RGCs) does a standard C57BL/6 laboratory mouse have on average and is this number substrain- or sex-dependent? Do RGCs of (European) C57BL/6J and -N mice show a different intrinsic vulnerability upon glaucomatous injury? Global RGC numbers and densities of common laboratory mice were previously determined via axon counts, retrograde tracing or BRN3A immunohistochemistry. Here, we report the global RGC number and density by exploiting the freely available tool RGCode to automatically count RGC numbers and densities on entire retinal wholemounts immunostained for the pan-RGC marker RBPMS. The intrinsic vulnerability of RGCs from different substrains to glaucomatous injury was evaluated upon introduction of the microbead occlusion model, followed by RBPMS counts, retrograde tracing and electroretinography five weeks post-injury. We demonstrate that the global RGC number and density varies between substrains, yet is not sex-dependent. C57BL/6J mice have on average 46K ± 2K RBPMS+ RGCs per retina, representing a global RGC density of 3268 ± 177 RGCs/mm2. C57BL/6N mice, on the other hand, have on average less RBPMS+ RGCs (41K ± 3K RGCs) and a lower density (3018 ± 189 RGCs/mm2). The vulnerability of the RGC population of the two C57BL/6 substrains to glaucomatous injury did, however, not differ in any of the interrogated parameters.
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Akter T, Annamalai B, Obert E, Simpson KN, Rohrer B. Dabigatran and Wet AMD, Results From Retinal Pigment Epithelial Cell Monolayers, the Mouse Model of Choroidal Neovascularization, and Patients From the Medicare Data Base. Front Immunol 2022; 13:896274. [PMID: 35784301 PMCID: PMC9248746 DOI: 10.3389/fimmu.2022.896274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 05/17/2022] [Indexed: 12/02/2022] Open
Abstract
Background Age-related macular degeneration (AMD), the leading cause of irreversible blindness in elderly Caucasian populations, includes destruction of the blood-retina barrier (BRB) generated by the retinal pigment epithelium-Bruch’s membrane complex (RPE/BrM), and complement activation. Thrombin is likely to get access to those structures upon BRB integrity loss. Here we investigate the potential role of thrombin in AMD by analyzing effects of the thrombin inhibitor dabigatran. Material and Methods MarketScan data for patients aged ≥65 years on Medicare was used to identify association between AMD and dabigatran use. ARPE-19 cells grown as mature monolayers were analyzed for thrombin effects on barrier function (transepithelial resistance; TER) and downstream signaling (complement activation, expression of connective tissue growth factor (CTGF), and secretion of vascular endothelial growth factor (VEGF)). Laser-induced choroidal neovascularization (CNV) in mouse is used to test the identified downstream signaling. Results Risk of new wet AMD diagnosis was reduced in dabigatran users. In RPE monolayers, thrombin reduced TER, generated unique complement C3 and C5 cleavage products, led to C3d/MAC deposition on cell surfaces, and increased CTGF expression via PAR1-receptor activation and VEGF secretion. CNV lesion repair was accelerated by dabigatran, and molecular readouts suggest that downstream effects of thrombin include CTGF and VEGF, but not the complement system. Conclusions This study provides evidence of association between dabigatran use and reduced exudative AMD diagnosis. Based on the cell- and animal-based studies, we suggest that thrombin modulates wound healing and CTGF and VEGF expression, making dabigatran a potential novel treatment option in AMD.
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Affiliation(s)
- Tanjina Akter
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
- *Correspondence: Tanjina Akter, ; Bärbel Rohrer,
| | | | - Elisabeth Obert
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
| | - Kit N. Simpson
- Department of Healthcare Leadership and Management, Medical University of South Carolina, Charleston, SC, United States
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, United States
- *Correspondence: Tanjina Akter, ; Bärbel Rohrer,
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Annamalai B, Parsons N, Nicholson C, Joseph K, Coughlin B, Yang X, Jones BW, Tomlinson S, Rohrer B. Natural immunoglobulin M-based delivery of a complement alternative pathway inhibitor in mouse models of retinal degeneration. Exp Eye Res 2021; 207:108583. [PMID: 33878326 PMCID: PMC8504679 DOI: 10.1016/j.exer.2021.108583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 03/31/2021] [Accepted: 04/13/2021] [Indexed: 11/23/2022]
Abstract
PURPOSE Age-related macular degeneration is a slowly progressing disease. Studies have tied disease risk to an overactive complement system. We have previously demonstrated that pathology in two mouse models, the choroidal neovascularization (CNV) model and the smoke-induced ocular pathology (SIOP) model, can be reduced by specifically inhibiting the alternative complement pathway (AP). Here we report on the development of a novel injury-site targeted inhibitor of the alternative pathway, and its characterization in models of retinal degeneration. METHODS Expression of the danger associated molecular pattern, a modified annexin IV, in injured ARPE-19 cells was confirmed by immunohistochemistry and complementation assays using B4 IgM mAb. Subsequently, a construct was prepared consisting of B4 single chain antibody (scFv) linked to a fragment of the alternative pathway inhibitor, fH (B4-scFv-fH). ARPE-19 cells stably expressing B4-scFv-fH were microencapsulated and administered intravitreally or subcutaneously into C57BL/6 J mice, followed by CNV induction or smoke exposure. Progression of CNV was analyzed using optical coherence tomography, and SIOP using structure-function analyses. B4-scFv-fH targeting and AP specificity was assessed by Western blot and binding experiments. RESULTS B4-scFv-fH was secreted from encapsulated RPE and inhibited complement in RPE monolayers. B4-scFv-fH capsules reduced CNV and SIOP, and western blotting for breakdown products of C3α, IgM and IgG confirmed a reduction in complement activation and antibody binding in RPE/choroid. CONCLUSIONS Data supports a role for natural antibodies and neoepitope expression in ocular disease, and describes a novel strategy to target AP-specific complement inhibition to diseased tissue in the eye. PRECIS AMD risk is tied to an overactive complement system, and ocular injury is reduced by alternative pathway (AP) inhibition in experimental models. We developed a novel inhibitor of the AP that targets an injury-specific danger associated molecular pattern, and characterized it in disease models.
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Affiliation(s)
| | - Nathaniel Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Crystal Nicholson
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Kusumam Joseph
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Beth Coughlin
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Xiaofeng Yang
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
| | - Bryan W Jones
- Department of Ophthalmology, University of Utah, Salt Lake City, UT, USA
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA; Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA; Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA; Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA.
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Schnabolk G, Obert E, Banda NK, Rohrer B. Systemic Inflammation by Collagen-Induced Arthritis Affects the Progression of Age-Related Macular Degeneration Differently in Two Mouse Models of the Disease. Invest Ophthalmol Vis Sci 2021; 61:11. [PMID: 33289791 PMCID: PMC7726584 DOI: 10.1167/iovs.61.14.11] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Purpose Age-related macular degeneration (AMD) shares similar risk factors and inflammatory responses with rheumatoid arthritis (RA). Previously, we identified increased risk for dry AMD among patients with RA compared to control subjects, using retrospective data analysis. In this current study, we investigate the role of systemic inflammation triggered in a murine model of arthritis on choroidal neovascularization and retinal pigment epithelium (RPE) degeneration mouse models. Methods Collagen-induced arthritis (CIA) was induced in C57BL/6J mice prior to laser-induced choroidal neovascularization (CNV; wet AMD model) or sodium iodate-induced retinal degeneration (NaIO3; dry AMD model). CNV lesion size and retinal thickness were quantified by optical coherence photography (OCT), visual function was analyzed using optokinetic response and electroretinography, RPE morphology was examined by immunohistochemistry, and inflammatory gene expression was analyzed by quantitative PCR. Results CIA mice demonstrated decreased spatial acuity and contrast sensitivity, whereas no difference was observed in the RPE-generated c-wave. CNV lesion size was decreased in CIA mice. NaIO3 decreased c-wave amplitude, as well as retinal thickness, which was augmented by CIA. NaIO3 treatment resulted in loss of normal RPE hexagonal shape, which was further aggravated by CIA. Increased Cxcl9 expression was observed in the presence of CIA and CIA combined with AMD. Disease severity differences were observed between sexes. Conclusions Our data suggest systemic inflammation by CIA results in increased pathology in a dry AMD model, whereas it reduces lesions in a wet AMD model. These findings highlight the need for additional investigation into the role of secondary inflammation and sex-based differences on AMD.
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Affiliation(s)
- Gloriane Schnabolk
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Elisabeth Obert
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Nirmal K Banda
- Division of Rheumatology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States.,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, South Carolina, United States
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Abstract
The inbred mouse strain C57BL/6 has been widely used as a background strain for spontaneous and induced mutations. Developed in the 1930s, the C57BL/6 strain
diverged into two major groups in the 1950s, namely, C57BL/6J and C57BL/6N, and more than 20 substrains have been established from them worldwide. We previously
reported genetic differences among C57BL/6 substrains in 2009 and 2015. Since then, dozens of reports have been published on phenotypic differences in
behavioral, neurological, cardiovascular, and metabolic traits. Substrains need to be chosen according to the purpose of the study because phenotypic
differences might affect the experimental results. In this paper, we review recent reports of phenotypic and genetic differences among C57BL/6 substrains, focus
our attention on the proper use of C57BL/6 and other inbred strains in the era of genome editing, and provide the life science research community wider
knowledge about this subject.
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Affiliation(s)
- Kazuyuki Mekada
- Department of Zoology, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 700-0005, Japan.,Experimental Animal Division, RIKEN BioResource Research Center, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan
| | - Atsushi Yoshiki
- Experimental Animal Division, RIKEN BioResource Research Center, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan
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Annamalai B, Parsons N, Brandon C, Rohrer B. The use of Matrigel combined with encapsulated cell technology to deliver a complement inhibitor in a mouse model of choroidal neovascularization. Mol Vis 2020; 26:370-377. [PMID: 32476817 PMCID: PMC7245607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/13/2020] [Indexed: 11/03/2022] Open
Abstract
Purpose Risk for age-related macular degeneration (AMD), a slowly progressing, complex disease, is tied to an overactive complement system. Efforts are under way to develop an anticomplement-based treatment to be delivered locally or systemically. We developed an alternative pathway (AP) inhibitor fusion protein consisting of a complement receptor-2 fragment linked to the inhibitory domain of factor H (CR2-fH), which reduces the size of mouse choroidal neovascularization (CNV) when delivered locally or systemically. Specifically, we confirmed that ARPE-19 cells genetically engineered to produce CR2-fH reduce CNV lesion size when encapsulated and placed intravitreally. We extend this observation by delivering the encapsulated cells systemically in Matrigel. Methods ARPE-19 cells were generated to stably express CR2 or CR2-fH, microencapsulated using sodium alginate, and injected subcutaneously in Matrigel into 2-month-old C57BL/6J mice. Four weeks after implantation, CNV was induced using argon laser photocoagulation. Progression of CNV was analyzed using optical coherence tomography. Bioavailability of CR2-fH was evaluated in Matrigel plugs with immunohistochemistry, as well as in ocular tissue with dot blots. Efficacy as an AP inhibitor was confirmed with protein chemistry. Results An efficacious number of implanted capsules to reduce CNV was identified. Expression of the fusion protein systemically did not elicit an immune response. Bioavailability studies showed that CR2-fH was present in the RPE/choroid fractions of the treated mice, and reduced CNV-associated ocular complement activation. Conclusions These findings indicate that systemic production of the AP inhibitor CR2-fH can reduce CNV in the mouse model.
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Affiliation(s)
| | - Nathaniel Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC
| | - Carlene Brandon
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC,Department of Neuroscience; Medical University of South Carolina, Charleston, SC,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC
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A combination of genetics and microbiota influences the severity of the obesity phenotype in diet-induced obesity. Sci Rep 2020; 10:6118. [PMID: 32273571 PMCID: PMC7145845 DOI: 10.1038/s41598-020-63340-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 03/30/2020] [Indexed: 12/03/2022] Open
Abstract
Obesity has emerged as a major global health problem and is associated with various diseases, such as metabolic syndrome, type 2 diabetes mellitus, and cardiovascular diseases. The inbred C57BL/6 mouse strain is often used for various experimental investigations, such as metabolic research. However, over time, genetically distinguishable C57BL/6 substrains have evolved. The manifestation of genetic alterations has resulted in behavioral and metabolic differences. In this study, a comparison of diet-induced obesity in C57BL/6JHanZtm, C57BL/6NCrl and C57BL/6 J mice revealed several metabolic and immunological differences such as blood glucose level and cytokine expression, respectively, among these C57BL/6 substrains. For example, C57BL/6NCrl mice developed the most pronounced adiposity, whereas C57BL/6 J mice showed the highest impairment in glucose tolerance. Moreover, our results indicated that the immunological phenotype depends on the intestinal microbiota, as the cell subset composition of the colon was similar in obese ex-GF B6NRjB6JHanZtm and obese B6JHanZtm mice. Phenotypic differences between C57BL/6 substrains are caused by a complex combination of genetic and microbial alterations. Therefore, in performing metabolic research, considering substrain-specific characteristics, which can influence the course of study, is important. Moreover, for unbiased comparison of data, the entire strain name should be shared with the scientific community.
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Capozzi ME, Savage SR, McCollum GW, Hammer SS, Ramos CJ, Yang R, Bretz CA, Penn JS. The peroxisome proliferator-activated receptor-β/δ antagonist GSK0660 mitigates retinal cell inflammation and leukostasis. Exp Eye Res 2019; 190:107885. [PMID: 31758977 DOI: 10.1016/j.exer.2019.107885] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 11/19/2019] [Accepted: 11/19/2019] [Indexed: 12/18/2022]
Abstract
Diabetic retinopathy (DR) is triggered by retinal cell damage stimulated by the diabetic milieu, including increased levels of intraocular free fatty acids. Free fatty acids may serve as an initiator of inflammatory cytokine release from Müller cells, and the resulting cytokines are potent stimulators of retinal endothelial pathology, such as leukostasis, vascular permeability, and basement membrane thickening. Our previous studies have elucidated a role for peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) in promoting several steps in the pathologic cascade in DR, including angiogenesis and expression of inflammatory mediators. Furthermore, PPARβ/δ is a known target of lipid signaling, suggesting a potential role for this transcription factor in fatty acid-induced retinal inflammation. Therefore, we hypothesized that PPARβ/δ stimulates both the induction of inflammatory mediators by Müller cells as well the paracrine induction of leukostasis in endothelial cells (EC) by Müller cell inflammatory products. To test this, we used the PPARβ/δ inhibitor, GSK0660, in primary human Müller cells (HMC), human retinal microvascular endothelial cells (HRMEC) and mouse retina. We found that palmitic acid (PA) activation of PPARβ/δ in HMC leads to the production of pro-angiogenic and/or inflammatory cytokines that may constitute DR-relevant upstream paracrine inflammatory signals to EC and other retinal cells. Downstream, EC transduce these signals and increase their synthesis and release of chemokines such as CCL8 and CXCL10 that regulate leukostasis and other cellular events related to vascular inflammation in DR. Our results indicate that PPARβ/δ inhibition mitigates these upstream (MC) as well as downstream (EC) inflammatory signaling events elicited by metabolic stimuli and inflammatory cytokines. Therefore, our data suggest that PPARβ/δ inhibition is a potential therapeutic strategy against early DR pathology.
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Affiliation(s)
- Megan E Capozzi
- Department of Molecular Physiology and Biophysics, Vanderbilt University, USA.
| | - Sara R Savage
- Department of Pharmacology, Vanderbilt University, USA
| | - Gary W McCollum
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, USA
| | - Sandra S Hammer
- Department of Cell and Developmental Biology, Vanderbilt University, USA
| | - Carla J Ramos
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, USA
| | - Rong Yang
- Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, USA
| | - Colin A Bretz
- Department of Cell and Developmental Biology, Vanderbilt University, USA
| | - John S Penn
- Department of Molecular Physiology and Biophysics, Vanderbilt University, USA; Department of Pharmacology, Vanderbilt University, USA; Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, USA; Department of Cell and Developmental Biology, Vanderbilt University, USA
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Microglial Cell Dysfunction in CRB1-Associated Retinopathies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1185:159-163. [PMID: 31884605 DOI: 10.1007/978-3-030-27378-1_26] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Inherited retinal diseases encompass a large group of clinically and genetically heterogeneous diseases estimated to affect two million people worldwide. Among these people, approximately 80,000 are or will become blind in their first decades of life due to mutations in both alleles of the Crumbs homologue-1 (CRB1) gene. Microglia are the resident immune surveyor cells in the retina, and their roles have been heavily studied in several retinal diseases, including retinitis pigmentosa (RP), age-related macular degeneration, and diabetic retinopathy. However, very little is known about the role of microglia in CRB1-associated retinopathies. Thus, we here summarize the main findings described in the literature concerning inflammation and the role of microglia in CRB1-patients and CRB1-rodent models.
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Annamalai B, Parsons N, Belhaj M, Brandon C, Potts J, Rohrer B. Encapsulated Cell Technology-Based Delivery of a Complement Inhibitor Reduces Choroidal Neovascularization in a Mouse Model. Transl Vis Sci Technol 2018; 7:3. [PMID: 29576927 PMCID: PMC5846441 DOI: 10.1167/tvst.7.2.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 12/19/2017] [Indexed: 12/28/2022] Open
Abstract
Purpose Age-related macular degeneration (AMD) is a slowly progressing disease, and risk appears to be tied to an overactive complement system. We have previously demonstrated that mouse choroidal neovascularization (CNV) and smoke-induced ocular pathology can be reduced with an alternative pathway (AP) inhibitor fusion protein consisting of a complement receptor-2 fragment linked to the inhibitory domain of factor H (CR2-fH) when delivered systemically. Here we developed an experimental approach with genetically engineered encapsulated ARPE-19 cells to produce CR2-fH intravitreally. Methods ARPE-19 cells were generated to stably express CR2 or CR2-fH, microencapsulated using sodium alginate, and injected intravitreally into 2-month-old C57BL/6J mice. CNV was induced using argon laser photocoagulation 4 weeks postinjection. Presence of capsules and progression of CNV was analyzed using optical coherence tomography. Bioavailability of CR2-fH was evaluated in retina sections by immunohistochemistry, and efficacy as an AP inhibitor by C3a ELISA. Results Secretion of CR2-fH or CR2 from encapsulated ARPE-19 cells was confirmed. An efficacious concentration of CR2-fH capsules to reduce CNV was identified. Bioavailability studies showed that CR2-fH was present in capsules and retinas of injected mice, and reduced CNV-associated ocular C3a production. Conclusions These findings indicate that the AP inhibitor CR2-fH, when generated intravitreally, can reduce CNV in mouse. Translational Relevance Encapsulated ARPE-19 cells secreting CR2-fH or perhaps other antiangiogenic or prosurvival factors might be useful as a potential therapeutic tool to treat age-related macular degeneration.
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Affiliation(s)
| | - Nathaniel Parsons
- Departments of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Marwa Belhaj
- Department of Cell Biology, University of South Carolina, Columbia, SC, USA
| | - Carlene Brandon
- Departments of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA
| | - Jay Potts
- Department of Cell Biology, University of South Carolina, Columbia, SC, USA
| | - Bärbel Rohrer
- Departments of Ophthalmology, Medical University of South Carolina, Charleston, SC, USA.,Neurosciences, Division of Research, Medical University of South Carolina, Charleston, SC, USA.,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC, USA
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14
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Schnabolk G, Parsons N, Obert E, Annamalai B, Nasarre C, Tomlinson S, Lewin AS, Rohrer B. Delivery of CR2-fH Using AAV Vector Therapy as Treatment Strategy in the Mouse Model of Choroidal Neovascularization. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2017; 9:1-11. [PMID: 29234687 PMCID: PMC5723362 DOI: 10.1016/j.omtm.2017.11.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/06/2017] [Indexed: 12/12/2022]
Abstract
Complement activation plays a significant role in age-related macular degeneration (AMD) pathogenesis, and polymorphisms interfering with factor H (fH) function, a complement alternative pathway (AP) inhibitor, are associated with increased AMD risk. We have previously validated an AP inhibitor, a fusion protein consisting of a complement receptor 2 fragment linked to the inhibitory domain of fH (CR2-fH) as an efficacious treatment for choroidal neovascularization (CNV) when delivered intravenously. Here we tested an alternative approach of AAV-mediated delivery (AAV5-VMD2-CR2-fH or AAV5-VMD2-mCherry) using subretinal delivery in C57BL/6J mice. Secretion of CR2-fH was confirmed in polarized retinal pigment epithelium (RPE) cells. A safe concentration of AAV5-VMD2-CR2-fH was identified using electroretinography, optical coherence tomography (OCT), RPE morphology, and antibody profiling. One month after gene delivery, CNV was induced using argon laser photocoagulation. OCT assessment demonstrated reduced CNV with AAV5-VMD2-CR2-fH administration. Bioavailability studies revealed that gene-therapy delivered similar levels of CR2-fH to the RPE/choroid as treatment by intravenous injections, and C3a ELISA verified reduced CNV-associated ocular C3a production. These results contribute to existing data illustrating the importance of the AP of complement in CNV development and its potential role in AMD treatment. Demonstration of AAV-vector efficacy opens new avenues for the development of treatment strategies.
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Affiliation(s)
- Gloriane Schnabolk
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Nathaniel Parsons
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Elisabeth Obert
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA
| | | | - Cecile Nasarre
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC 29425, USA.,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC 29401, USA
| | - Alfred S Lewin
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville FL 32611, USA
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA.,Ralph H. Johnson VA Medical Center, Division of Research, Charleston, SC 29401, USA
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15
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Lajko M, Cardona HJ, Taylor JM, Farrow KN, Fawzi AA. Photoreceptor oxidative stress in hyperoxia-induced proliferative retinopathy accelerates rd8 degeneration. PLoS One 2017; 12:e0180384. [PMID: 28671996 PMCID: PMC5495396 DOI: 10.1371/journal.pone.0180384] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/14/2017] [Indexed: 12/13/2022] Open
Abstract
To investigate the impact of photoreceptor oxidative stress on photoreceptor degeneration in mice carrying the rd8 mutation (C57BL/6N). We compared the hyperoxia-induced proliferative retinopathy (HIPR) model in two mouse strains (C57BL/6J and C57BL/6N). Pups were exposed to 75% oxygen, starting at birth and continuing for 14 days (P14). Mice were euthanized at P14, or allowed to recover in room air for one day (P15), seven days (P21), or 14 days (P28). We quantified retinal thickness and the length of residual photoreceptors not affected by rosette formation. In addition we explored differences in retinal immunostaining for NADPH oxidase 4 (NOX4), Rac1, vascular endothelium, and activated Mϋller cells. We analyzed photoreceptor oxidative stress using DCF staining in cross sections and quantified NOX4 protein levels using western blotting. C57BL/6N mice in HIPR showed increased oxidative stress, NOX4, and Rac1 in the photoreceptors at P14 and P15 compared to C57BL/6J. In addition, we observed significant progression of photoreceptor degeneration, with significantly accelerated rosette formation in C57BL/6N under HIPR, compared to their room air counterparts. Furthermore, C57BL/6N under HIPR had significantly thinner central retinas than C57BL/6J in HIPR. We did not find a difference in vascular disruption or Mϋller cell activation comparing the two strains in hyperoxia. In HIPR, the C57BL/6N strain carrying the rd8 mutation showed significantly accelerated photoreceptor degeneration, mediated via exacerbated photoreceptor oxidative stress, which we believe relates to Rac1-NOX dysregulation in the setting of Crb1 loss-of-function.
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Affiliation(s)
- Michelle Lajko
- Department of Ophthalmology, Feinberg School of Medicine at Northwestern University, Chicago, Illinois, United States of America
| | - Herminio J. Cardona
- Department of Pediatrics, Feinberg School of Medicine at Northwestern University, Chicago, Illinois, United States of America
| | - Joann M. Taylor
- Department of Pediatrics, Feinberg School of Medicine at Northwestern University, Chicago, Illinois, United States of America
| | - Kathryn N. Farrow
- Department of Pediatrics, Feinberg School of Medicine at Northwestern University, Chicago, Illinois, United States of America
| | - Amani A. Fawzi
- Department of Ophthalmology, Feinberg School of Medicine at Northwestern University, Chicago, Illinois, United States of America
- * E-mail:
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16
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Song D, Wilson B, Zhao L, Bhuyan R, Bandyopadhyay M, Lyubarsky A, Yu C, Li Y, Kanu L, Miwa T, Song WC, Finnemann SC, Rohrer B, Dunaief JL. Retinal Pre-Conditioning by CD59a Knockout Protects against Light-Induced Photoreceptor Degeneration. PLoS One 2016; 11:e0166348. [PMID: 27893831 PMCID: PMC5125596 DOI: 10.1371/journal.pone.0166348] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 10/27/2016] [Indexed: 11/25/2022] Open
Abstract
Complement dysregulation plays a key role in the pathogenesis of age-related macular degeneration (AMD), but the specific mechanisms are incompletely understood. Complement also potentiates retinal degeneration in the murine light damage model. To test the retinal function of CD59a, a complement inhibitor, CD59a knockout (KO) mice were used for light damage (LD) experiments. Retinal degeneration and function were compared in WT versus KO mice following light damage. Gene expression changes, endoplasmic reticulum (ER) stress, and glial cell activation were also compared. At baseline, the ERG responses and rhodopsin levels were lower in CD59aKO compared to wild-type (WT) mice. Following LD, the ERG responses were better preserved in CD59aKO compared to WT mice. Correspondingly, the number of photoreceptors was higher in CD59aKO retinas than WT controls after LD. Under normal light conditions, CD59aKO mice had higher levels than WT for GFAP immunostaining in Müller cells, mRNA and protein levels of two ER-stress markers, and neurotrophic factors. The reduction in photon capture, together with the neurotrophic factor upregulation, may explain the structural and functional protection against LD in the CD59aKO.
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Affiliation(s)
- Delu Song
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
| | - Brooks Wilson
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC
| | - Liangliang Zhao
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
- Department of Ophthalmology, The Second Hospital of Jilin University, Jilin, China
| | - Rupak Bhuyan
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
| | | | - Arkady Lyubarsky
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
| | - Chen Yu
- Center for Cancer, Genetic Diseases, and Gene Regulation, Department of Biological Sciences, Fordham University, Bronx, NY
| | - Yafeng Li
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
| | - Levi Kanu
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
| | - Takashi Miwa
- Department of Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Wen-Chao Song
- Department of Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Silvia C. Finnemann
- Center for Cancer, Genetic Diseases, and Gene Regulation, Department of Biological Sciences, Fordham University, Bronx, NY
| | - Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC
- Research Service, Ralph H. Johnson VA Medical Center, Charleston, SC
- * E-mail: (JLD); (BR)
| | - Joshua L. Dunaief
- The F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at University of Pennsylvania, Philadelphia, PA
- * E-mail: (JLD); (BR)
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Sturm M, Becker A, Schroeder A, Bilkei-Gorzo A, Zimmer A. Effect of chronic corticosterone application on depression-like behavior in C57BL/6N and C57BL/6J mice. GENES BRAIN AND BEHAVIOR 2015; 14:292-300. [DOI: 10.1111/gbb.12208] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 02/21/2015] [Accepted: 02/26/2015] [Indexed: 02/01/2023]
Affiliation(s)
- M. Sturm
- Institute of Molecular Psychiatry; University of Bonn; Bonn Germany
| | - A. Becker
- Institute of Molecular Psychiatry; University of Bonn; Bonn Germany
| | - A. Schroeder
- Institute of Molecular Psychiatry; University of Bonn; Bonn Germany
| | - A. Bilkei-Gorzo
- Institute of Molecular Psychiatry; University of Bonn; Bonn Germany
| | - A. Zimmer
- Institute of Molecular Psychiatry; University of Bonn; Bonn Germany
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18
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Schnabolk G, Coughlin B, Joseph K, Kunchithapautham K, Bandyopadhyay M, O'Quinn EC, Nowling T, Rohrer B. Local production of the alternative pathway component factor B is sufficient to promote laser-induced choroidal neovascularization. Invest Ophthalmol Vis Sci 2015; 56:1850-63. [PMID: 25593023 DOI: 10.1167/iovs.14-15910] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
PURPOSE Complement factor B (CFB) is a required component of the alternative pathway (AP) of complement, and CFB polymorphisms are associated with age-related macular degeneration (AMD) risk. Complement factor B is made in the liver, but expression has also been detected in retina and retinal pigment epithelium (RPE)-choroid. We investigated whether production of CFB by the RPE can promote AP activation in mouse choroidal neovascularization (CNV). METHODS Transgenic mice expressing CFB under the RPE65 promoter were generated and crossed onto factor B-deficient (CFB-KO) mice. Biological activity was determined in vitro using RPE monolayers and in vivo using laser-induced CNV. Contribution of systemic CFB was investigated using CFB-KO reconstituted with CFB-sufficient serum. RESULTS Transgenic mice (CFB-tg) expressed CFB in RPE-choroid; no CFB was detected in serum. Cultured CFB-tg RPE monolayers secreted CFB apically and basally upon exposure to oxidative stress that was biologically active. Choroidal neovascularization sizes were comparable between wild-type and CFB-tg mice, but significantly increased when compared to lesions in CFB-KO mice. Injections of CFB-sufficient serum into CFB-KO mice resulted in partial reconstitution of systemic AP activity and significantly increased CNV size. CONCLUSIONS Mouse RPE cells express and secrete CFB sufficient to promote RPE damage and CNV. This further supports that local complement production may regulate disease processes; however, the reconstitution experiments suggest that additional components may be sequestered from the bloodstream. Understanding the process of ocular complement production and regulation will further our understanding of the AMD disease process and the requirements of a complement-based therapeutic.
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Affiliation(s)
- Gloriane Schnabolk
- Research Service, Ralph H. Johnson VA Medical Center, Charleston, South Carolina, United States
| | - Beth Coughlin
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Kusumam Joseph
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Kannan Kunchithapautham
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Mausumi Bandyopadhyay
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Elizabeth C O'Quinn
- Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Tamara Nowling
- Department of Medicine, Division of Rheumatology and Immunology, Medical University of South Carolina, Charleston, South Carolina, United States
| | - Bärbel Rohrer
- Research Service, Ralph H. Johnson VA Medical Center, Charleston, South Carolina, United States Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina, United States
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