scholarly journals Decreased membrane complement regulators in the retinal pigmented epithelium contributes to age-related macular degeneration

2013 ◽  
Vol 229 (5) ◽  
pp. 729-742 ◽  
Author(s):  
Katayoon B Ebrahimi ◽  
Natalia Fijalkowski ◽  
Marisol Cano ◽  
James T Handa
2020 ◽  
Vol 79 ◽  
pp. 100859
Author(s):  
Luminita Paraoan ◽  
Umar Sharif ◽  
Emil Carlsson ◽  
Wasu Supharattanasitthi ◽  
Nur Musfirah Mahmud ◽  
...  

2021 ◽  
Author(s):  
Meenakshi Ambati ◽  
Ivana Apicella ◽  
Siddharth Narendran ◽  
Shao-bin Wang ◽  
Hannah Leung ◽  
...  

AbstractThe atrophic form of age-related macular degeneration (dry AMD) affects nearly 200 million people worldwide. There is no FDA-approved therapy for this disease, which is the leading cause of irreversible blindness among people over 50 years of age. Vision loss in dry AMD results from degeneration of the retinal pigmented epithelium (RPE). RPE cell death is driven in part by accumulation of Alu RNAs, which are noncoding transcripts of a human retrotransposon. Alu RNA induces RPE degeneration by activating the NLRP3-ASC inflammasome. We report that fluoxetine, an FDA-approved drug for treating clinical depression, binds NLRP3 in silico, in vitro, and in vivo, and that it inhibits activation of the NLRP3-ASC inflammasome in RPE cells and macrophages, two critical cell types in dry AMD. We also demonstrate that fluoxetine, unlike several other anti-depressant drugs, reduces Alu RNA-induced RPE degeneration in mice. Finally, by analyzing two health insurance databases comprising more than 100 million Americans, we report a reduced hazard of developing dry AMD among patients with depression who were treated with fluoxetine. Collectively, these studies triangulate to link fluoxetine as a potential drug repurposing candidate for a major unmet medical need that causes blindness in millions of people in the United States and across the world.Significance StatementDry age-related macular degeneration (AMD) affects the vision of millions of people worldwide. There is currently no FDA-approved treatment for dry AMD. The inflammasome components NLRP3 and ASC have been implicated in the pathogenesis of dry AMD. We report that fluoxetine, which is approved for the treatment of clinical depression, directly binds the NLRP3 protein and prevents the assembly and activation of the NLRP3-ASC inflammasome. As a result, it also blocks the degeneration of retinal pigmented epithelium (RPE) cells in an animal model of dry AMD. Furthermore, we demonstrate through an analysis of health insurance databases that use of this FDA-approved anti-depressant drug is associated with reduced incidence of dry AMD. These studies identify that fluoxetine is a potential repurposing candidate for AMD, a prevalent cause of blindness.


PLoS ONE ◽  
2017 ◽  
Vol 12 (3) ◽  
pp. e0173575 ◽  
Author(s):  
Zhouhui Geng ◽  
Patrick J. Walsh ◽  
Vincent Truong ◽  
Caitlin Hill ◽  
Mara Ebeling ◽  
...  

2019 ◽  
Author(s):  
Jesse G. Meyer ◽  
Thelma Garcia ◽  
Birgit Schilling ◽  
Bradford W. Gibson ◽  
Deepak A. Lamba

AbstractAge-related macular degeneration (AMD) is the leading cause of blindness in developed countries, and is characterized by slow retinal degeneration linked to chronic oxidative stress in the retinal pigmented epithelium (RPE). The exact molecular mechanisms that lead to RPE death and dysfunction in response to chronic reactive oxygen species (ROS) are still unclear. In this work, human stem cell-derived RPE samples were treated with a low dose of paraquat (PQ) for 1 week or 3 weeks to induce chronic reactive oxygen species (ROS) stress. Cells were then harvested and both the intracellular and secreted RPE proteomes were quantified by mass spectrometry. Inside the RPE, chronic ROS caused concerted increase of glycolytic proteins but decreased mitochondrial proteins, as well as decreased extracellular matrix proteins and membrane proteins required for endocytosis. From the secreted proteins, we found that stressed RPE secrete over 1,000 detectable proteins, and the composition of the proteins secreted from RPE changes due to chronic ROS. Notably, secreted APOE is decreased 4-fold due to 3 weeks of chronic ROS stress, and urotensin-II, the strongest known vasoconstrictor, doubles. Further, secreted TGF-beta is increased, and its cognate signaler BMP1 decreased in the secretome. Together, these alterations of the RPE proteome and protein secretome paint a detailed molecular picture of the retinal stress response in space and time.


2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Fernando H. Lojudice ◽  
Rodrigo A. Brant Fernandes ◽  
Francesco Innocenti ◽  
Carlos E. Franciozi ◽  
Priscila Cristovam ◽  
...  

Abstract Background The World Health Organization (WHO) estimates that the number of individuals who lose their vision due to retinal degeneration is expected to reach 6 million annually in 2020. The retinal degenerative diseases affect the macula, which is responsible for central and detailed vision. Most macular degeneration, i.e., age-related macular degeneration (AMD) develops in the elderly; however, certain hereditary diseases, such as the Stargardt disease, also affect young people. This degeneration begins with loss of retinal pigmented epithelium (RPE) due to formation of drusen (atrophic) or abnormal vessels (exudative). In wet AMD, numerous drugs are available to successful treat the disease; however, no proven therapy currently is available to treat dry AMD or Stargardt. Since its discovery, human embryonic stem cells (hESCs) have been considered a valuable therapeutic tool. Some evidence has shown that transplantation of RPEs differentiated from hESCs cells can result in recovery of both RPE and photoreceptors and prevent visual loss. Methods The human embryonic WA-09 stem cell lineage was cultured under current Good Manufacturing Practices (cGMP) conditions using serum-free media and supplements. The colonies were isolated manually and allowed to spontaneously differentiate into RPE cells. Results This simple and effective protocol required minimal manipulation and yielded more than 10e8 RPE cells by the end of the differentiation and enrichment processes, with cells exhibiting a cobblestone morphology and displaying cellular markers and a gene expression profile typical of mature RPE cells. Moreover, the differentiated cells displayed phagocytic activity and only a small percentage of the total cells remained positive for the Octamer-binding transcriptions factor 4 (OCT-4) pluripotency cell marker. Conclusions These results showed that functional RPE cells can be produced efficiently and suggested the possibility of scaling-up to aim at therapeutic protocols for retinal diseases associated with RPE degeneration.


Author(s):  
O.Y. Kuznetsova ◽  
◽  
D.V. Peregudov ◽  
D.V. Levina ◽  
A.Y. Novikova. ◽  
...  

Purpose. To evaluate the efficiency of Aflibercept in patients with various vas-cular and neovascular diseases of the retina. Material and methods. 43 patients (55 eyes) with various ophthalmic patholo-gies were treated: wet form of age-related macular degeneration of the retina (AMD), myopic CNV, diabetic macular edema (DME) and macular edema due to occlusion of the retinal veins. Among them, 17 (39.5%) men and 26 (60.5%) women aged 38 to 84 years (62±1.9 years). All patients underwent a compre-hensive ophthalmological examination. A total of 158 intravitreal injections (IVI) of Aflibercept were performed. The observation period was 6 months. The efficiency of treatment was assessed according to the data of visual acuity, OCT, as well as subjective feelings and changes in the area of central scotoma. Results. Visual acuity among all patients after three loading injections increased by an average of 2.8 lines. Subjective improvement in visual functions was noted in 38 (89%) patients. The greatest increase in visual functions was observed in the exudative form of wet AMD, which manifests itself mainly in the form of detachment and / or edema of the neuroepithelium. The smallest in-crease in visual acuity was observed in patients with exudative-hemorrhagic form of wet AMD with detachment of the pigmented epithelium and neuroepi-thelium, as well as in myopic CNV. Over the next three months after the course of loading injections, visual acuity increased by an average of 5-7%. The thick-ness of the retina in the fovea decreased by an average of 156.8 ± 52 µm (from 45 to 290 µm), while the greatest decrease in the thickness was observed in pa-tients with DMO and exudative form of wet AMD, manifested as detachment of neuro- and pigmented epithelium, and the least expressed was in myopic CNV. Conclusion. The use of IVV Aflibercept is effective in various vascular and ne-ovascular diseases of the retina. The highest functional result is observed in pa-tients with an exudative form of wet AMD, manifested by detachment and / or edema of the neuroepithelium. Key words: аflibercept, intravitreal injection, vascular endothelial growth fac-tor, age-related macular degeneration, macular edema.


2014 ◽  
Vol 144 (6) ◽  
pp. 799-806 ◽  
Author(s):  
Jung-Heun Ha ◽  
Pollob Kumar Shil ◽  
Ping Zhu ◽  
Liwei Gu ◽  
Qiuhong Li ◽  
...  

Abstract Inflammation and endoplasmic reticulum (ER) stress are common denominators for vision-threatening diseases such as diabetic retinopathy and age-related macular degeneration. Based on our previous study, supplementation with muscadine grape polyphenols (MGPs) alleviated systemic insulin resistance and proinflammatory responses. In this study, we hypothesized that MGPs would also be effective in attenuating ocular inflammation and ER stress. We tested this hypothesis using the human retinal pigmented epithelium (ARPE-19) cells and C57BL/6 mice. In ARPE-19 cells, tumor necrosis factor-α–induced proinflammatory gene expression of interleukin (IL)-1β, IL-6, and monocyte chemotactic protein-1 was decreased by 35.0%, 68.8%, and 62.5%, respectively, with MGP pretreatment, which was primarily due to the diminished mitogen-activated protein kinase activation and subsequent reduction of nuclear factor κ-B activation. Consistently, acute ocular inflammation and leukocyte infiltration were almost completely dampened (>95%) by MGP supplementation (100–200 mg/kg body weight) in C57BL/6 mice. Moreover, MGPs reduced inflammation-mediated loss of tight junctions and retinal permeability. To further investigate the protective roles of MGPs against ER stress, ARPE-19 cells were stimulated with thapsigargin. Pretreatment with MGPs significantly decreased the following: 1) ER stress-mediated vascular endothelial growth factor secretion (3.47 ± 0.06 vs. 1.58 ± 0.02 μg/L, P< 0.0001), 2) unfolded protein response, and 3) early apoptotic cell death (64.4 ± 6.85 vs. 33.7 ± 4.32%, P= 0.0003). Collectively, we have demonstrated that MGP is effective in attenuating ocular inflammation and ER stress. Our work also suggests that MGP may provide a novel dietary strategy to prevent vision-threatening retinal diseases.


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