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The effect of AREDS MVS and ZnCl 2 on EC (C166) viability. (A) AREDS MVS-treated cell death rate at the 4th, 24th, and 56th hours after treatment. (B) ZnCl 2 -treated cell death rate at the 4th, 24th, and 56th hours after treatment. Increased cell death was observed only in EC exposed to 100 M ZnCl 2 .
Source publication
To investigate whether the benefit of Age-Related Eye Disease Study (AREDS) formula multivitamins and zinc in the progression of age-related macular degeneration (AMD) may occur through inhibiting inflammatory events in the choroid.
Mouse C166 endothelial cells (ECs) and, for some experiments, human retinal pigment epithelium (RPE)-choroid organ cu...
Context in source publication
Context 1
... colorimetric LDH assay showed no significant cytotoxicity of MVS at concentrations of 1 and 5 and zinc at concentra- tions of 20 and 60 M until 56 hours after treatment but a remarkable increase in the cell death rate (94.2%) at a concen- tration of 100 M at the 56th hour after treatment (P 0.05) (Figs. 1A, ...
Citations
... The AREDS formulation is the most promising option since it has been shown to delay the disease progression from intermediate to the advanced disease stage in one out of every four cases (Age-Related Eye Disease Study Research Group, 1999Group, , 2001Chew et al., 2013;Michalska-Małecka et al., 2014). In mouse endothelial cells and in human retinal pigment epithelium-choroid organ cultures, AREDS treatment showed the potential to reduce angiogenesis and inhibited the interaction of macrophages with the endothelium (Zeng et al., 2012). Combination treatments, such as the AREDS-like formulation, targeting multiple pathways in a multifactorial AMD disease have been proposed to be a potential treatment option (Cabral De Guimaraes et al., 2022;Michalska-Małecka et al., 2014). ...
Age‐related macular degeneration (AMD) is an eye disease, which causes impaired vision that can lead to blindness. The incidence of AMD increases with age. Retinal pigment epithelial (RPE) cells maintain retinal homeostasis and support the functionality of photoreceptors. In the pathogenesis of AMD, the degeneration of the RPE cells precedes photoreceptor cell death. RPE cells are susceptible to oxidative stress, and chronic inflammation involving nucleotide‐binding domain, leucine‐rich repeat and pyrin domain 3 (NLRP3) inflammasome activation and impaired autophagy are challenges faced by aged RPE cells in AMD. There are two types of AMD, dry (85–90%) and wet (10–15%) disease forms. Choroidal neovascularization is typical for wet AMD, and anti‐vascular endothelial growth factor (anti‐VEGF) injections are used to prevent the progression of the disease but there is no curative treatment. There is no cure for the dry disease form, but antioxidants have been proposed as a potential treatment option.
Ageing is the most important risk factor of AMD, and tobacco smoke is the most important environmental risk factor that can be controlled. Hydroquinone is a cytotoxic, immunotoxic, carcinogenic and pro‐oxidative component of tobacco smoke. The aim of this PhD thesis was to study hydroquinone‐induced oxidative stress and NLRP3 inflammasome activation in human RPE cells (ARPE‐19 cells). An age‐related eye disease study (AREDS) formulation (incl. omega‐3 fatty acids, vitamin C and E, copper, zinc, lutein and zeaxanthin), which is clinically investigated p.o. dosing combination of dietary supplements for AMD patients, has been evaluated as a possible treatment and restraining option for AMD. Resvega (4.1.1, Table 2) is a similar kind of product to AREDS with added resveratrol, and many of the components incorporated within Resvega can be considered as belonging to the normal antioxidative defence system of the retina. Another aim was to evaluate the effects of Resvega on hydroquinone‐induced oxidative stress or NLRP3 inflammasome activation induced by impaired protein clearance.
The results of this study reveal that hydroquinone elevated the activity of NADPH oxidase which subsequently mediated the production of reactive oxygen species (ROS) and predisposed RPE cells to degeneration by reducing levels of vascular endothelial growth factor (VEGF) and pigment epithelium‐derived factor (PEDF). Hydroquinone induced an NLRP3‐independent IL‐18 release and NLRP3 accumulation inside the IL‐1α‐primed cells. Resvega treatment reduced the extent of hydroquinone‐induced ROS production and NLRP3 inflammasome activation evoked by impaired protein clearance. Thus, Resvega alleviated hydroquinone‐ and impaired protein clearance‐induced stress in human RPE cells, but more studies are needed, for example, to reveal the most optimal route of administration for targeting the cells in the retina, since both oxidative stress and NLRP3 inflammasome activation are important contributors to the development of AMD and represent significant treatment targets.
... For example, genistein, a flavonoid, and resveratrol, serine/arginine-rich protein kinase (SRPK), and curcumin have an anti-angiogenic effect in reducing ICAM-1 (but also MMP-9 and MCP-1) (Kinoshita et al., 2014;Nagai et al., 2014). AREDS multivitamin solution and zinc seem to decrease ICAM-1 expression (Zeng et al. 2012). Genistein is a tyrosine kinase inhibitor, which inhibits CNV but also inhibits choriocapillaris regeneration which could attenuate a full recovery . ...
The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.
... Their observations showed that this formulation acts via decreasing inflammatory cascade in the vascular layer of the eye. Additionally, they found that this improvement is in part a result of the attenuation of endothelial cell activation and a decreased release of ICAM-1 and VCAM-1 (Zeng et al., 2012). Rossella et al. conducted a study in 2017 to examine the possible effect of zinc nanoparticles. ...
... As mentioned before, the conducted study by Young-Eun Cho and colleagues showed that zinc is effective in alleviating both VCAM-1 and ICAM-1 which are markers of atherosclerosis (Cho et al., 2008). As stated before, the results from the study of Sbemin et al. revealed that the mean by which zinc-containing formulations meliorate macular degeneration is through diminishing inflammation and endothelial activation that eventuate to a reduction in the production of the ICAM-1 and VCAM-1 (Zeng et al., 2012). Elevation (but not significant) in the levels of the ICAM-1 and soluble form of E-selectin in response to low zinc intake was observed in a study that was done in the United Kingdom by John H. Beattie, and coworkers (Beattie et al., 2012). ...
Background:
Cardiovascular health is strongly influenced by diet. The levels of inflammatory factors like ICAM-1 and VCAM-1 are high in patients with atherosclerosis or predisposing factor for heart disease. Antioxidant and anti-inflammatory functions are attributed to zinc. We systematically reviewed cell culture, human or animal studies for determining the relationship between zinc status and ICAMs or VCAM-1 levels.
Methods:
PubMed, Google Scholar, Scopus, and Cochrane databases from database inception till 30th August 2020 were systematically searched to obtain any possible article for inclusion.
Results:
After screening and removing unrelated or duplicate articles by the title and abstract by two independent reviewers, 15 articles were included. Results indicating an inverse relationship between zinc status with ICAM-1 or VCAM-1 levels and the development of endothelial inflammation, plaque formation, or atherosclerosis. A direct relationship between zinc status and PPAR-α or γ levels was also observed. Zinc oxide (ZnO), zinc nanoparticles, or ions can cause endothelial activation and increased levels of ICAM-1 and VCAM-1.
Conclusion:
Normal function of the endothelium is linked with zinc level. Zinc deficiency causes atherosclerosis, most probably via increased production of ICAM-1 and VCAM-1; and decreased expression of PPAR-ɑ and PPAR-γ receptors. Contrarily, endothelial activation and increased ICAM-1 and VCAM-1 levels can be caused by ZnO, zinc nanoparticles, or zinc ions.
... Reverse transcription was performed in a 50-µl reaction using a reverse transcription kit (MultiScribe; Thermo Fisher Scientific). IHH expression was determined by real-time PCR (NM_002181, 59-ATGACCCAGCGCTGCAAG-39 and 59-CAAAGCCGGCCTCCACTG-39) as described previously (Zeng et al., 2012) using RPL19 expression for normalization (NM_000981, 59-ATGCCAACTCCCGTCAGC-39 and 59-ACCCTTCCGCTTACCTATGC-39) and calculating relative expression values by the 2 −ΔΔCt method. All samples were analyzed in technical triplicates. ...
The activity and survival of retinal photoreceptors depend on support functions performed by the retinal pigment epithelium (RPE) and on oxygen and nutrients delivered by blood vessels in the underlying choroid. By combining single-cell and bulk RNA sequencing, we categorized mouse RPE/choroid cell types and characterized the tissue-specific transcriptomic features of choroidal endothelial cells. We found that choroidal endothelium adjacent to the RPE expresses high levels of Indian Hedgehog and identified its downstream target as stromal GLI1⁺ mesenchymal stem cell–like cells. In vivo genetic impairment of Hedgehog signaling induced significant loss of choroidal mast cells, as well as an altered inflammatory response and exacerbated visual function defects after retinal damage. Our studies reveal the cellular and molecular landscape of adult RPE/choroid and uncover a Hedgehog-regulated choroidal immunomodulatory signaling circuit. These results open new avenues for the study and treatment of retinal vascular diseases and choroid-related inflammatory blinding disorders. © 2020 Lehmann et al. This article is available under a Creative Commons License (Attribution 4.0 International, as described at https://creativecommons.org/licenses/by/4.0/).
... Vascular endothelial cells of the choriocapillaris are known to exhibit distinctive characteristics at the biochemical and structural levels. They express high levels of ICAM1 at resting states (although this constitutive ICAM1 expression increases during inflammatory challenge) (53)(54)(55), PLVAP (37) (a constituent of their fenestrae diaphragms), MHC class I antigens (56), and carbonic anhydrase IV (CA4) (11) in contrast to other ocular endothelial cells. These unique molecular features may contribute to the susceptibility of the choriocapillaris to molecular insults that are implicated in AMD pathogenesis. ...
The human retinal pigment epithelium (RPE) and choroid are complex tissues that provide crucial support to the retina. Disease affecting either of these supportive tissues can lead to irreversible blindness in the setting of age-related macular degeneration. In this study, single-cell RNA sequencing was performed on macular and peripheral regions of RPE-choroid from 7 human donor eyes in 2 independent experiments. In the first experiment, total RPE/choroid preparations were evaluated and expression profiles specific to RPE and major choroidal cell populations were identified. As choroidal endothelial cells represent a minority of the total RPE/choroidal cell population but are strongly implicated in age-related macular degeneration (AMD) pathogenesis, a second single-cell RNA-sequencing experiment was performed using endothelial cells enriched by magnetic separation. In this second study, we identified gene expression signatures along the choroidal vascular tree, classifying the transcriptome of human choriocapillaris, arterial, and venous endothelial cells. We found that the choriocapillaris highly and specifically expresses the regulator of cell cycle gene ( RGCC ), a gene that responds to complement activation and induces apoptosis in endothelial cells. In addition, RGCC was the most up-regulated choriocapillaris gene in a donor diagnosed with AMD. These results provide a characterization of the human RPE and choriocapillaris transcriptome, offering potential insight into the mechanisms of choriocapillaris response to complement injury and choroidal vascular disease in age-related macular degeneration.
... In vitro studies have suggested that AREDS vitamins and zinc supplementation attenuate angiogenesis and endothelial-macrophage interactions, thereby reducing the progression of AMD [84]. Finally, data from an animal model of light-induced retinal degeneration suggest that integration with zinc induces changes in gene expression, as well as enhances the antioxidative power in the retina and reduces the oxidative damage that arises from intense light exposure. ...
Age-related macular degeneration (AMD) is a complex multifactorial disease and the primary cause of legal and irreversible blindness among individuals aged ≥65 years in developed countries. Globally, it affects 30–50 million individuals, with an estimated increase of approximately 200 million by 2020 and approximately 300 million by 2040. Currently, the neovascular form may be able to be treated with the use of anti-VEGF drugs, while no effective treatments are available for the dry form. Many studies, such as the randomized controlled trials (RCTs) Age-Related Eye Disease Study (AREDS) and AREDS 2, have shown a potential role of micronutrient supplementation in lowering the risk of progression of the early stages of AMD. Recently, low-grade inflammation, sustained by dysbiosis and a leaky gut, has been shown to contribute to the development of AMD. Given the ascertained influence of the gut microbiota in systemic low-grade inflammation and its potential modulation by macro- and micro-nutrients, a potential role of diet in AMD has been proposed. This review discusses the role of the gut microbiota in the development of AMD. Using PubMed, Web of Science and Scopus, we searched for recent scientific evidence discussing the impact of dietary habits (high-fat and high-glucose or -fructose diets), micronutrients (vitamins C, E, and D, zinc, beta-carotene, lutein and zeaxanthin) and omega-3 fatty acids on the modulation of the gut microbiota and their relationship with AMD risk and progression.
... In vitro studies have suggested that AREDS vitamins and zinc supplementation attenuate angiogenesis and endothelial-macrophage interactions, thereby reducing the progression of AMD [84]. Finally, data from an animal model of light-induced retinal degeneration suggest that integration with zinc induces changes in gene expression, as well as enhances the antioxidative power in the retina and reduces the oxidative damage that arises from intense light exposure. ...
Age-related macular degeneration (AMD) is a complex multifactorial disease and the primary cause of legal and irreversible blindness among individuals aged >=65 years in developed countries. Globally, it affects 30-50 million individuals, with an estimated increase of approximately 200 million by 2020 and approximately 300 million by 2040. Currently, the neovascular form may be able to be treated with the use of anti-VEGF drugs, while no effective treatments are available for the dry form. Many observational studies, such as AREDS-1 and AREDS 2, have shown a potential role of micronutrient supplementation in lowering the risk of progression of the early stages of AMD. Recently, low-grade inflammation, sustained by dysbiosis and a leaky gut, has been shown to contribute to the development of AMD. Given the ascertained influence of the gut microbiota in systemic low-grade inflammation and its potential modulation by macro- and micro-nutrients, a potential role of diet in AMD has been proposed. This review discusses the role of the gut microbiota in the development of AMD. Using PubMed, Web of Science and Scopus, we searched for recent scientific evidence discussing the impact of dietary habits (high fat and high glucose or fructose diets), micronutrients (vitamins C, E, and D, zinc, beta-carotene, lutein and zeaxanthin) and omega-3 fatty acids on the modulation of the gut microbiota and their relationship with AMD risk and progression.
... Utrzymanie równowagi pomiędzy antyoksydantami (przeciwutleniaczami), a oksydantami (utleniacze) w układach biologicznych jest bardzo ważna. Zachwianie tej równowagi może niestety uszkodzić tkanki oczne i doprowadzić do ciężkich w skutkach chorób oczu (nawet do utraty wzroku)[Haddad 2012; Bartosz Grzegorz 2013;Thiagarajan i Manikandan 2013;Zeng, Hernández, i Mullins 2012]. Do jednych z ważniejszych i niebezpiecznych właściwości RFT należy generowanie uszkodzeń w szlakach metabolicznych, uwarunkowaniach fizycznych oraz chemicznych. ...
... An outstanding question in relation to AMD is how zinc supplementation exerts its observed beneficial effect [56][57][58][59]. Here we report that one of the ways is through direct effects on the RPE cells. ...
Population-based and interventional studies have shown that elevated zinc levels can reduce the progression to advanced age-related macular degeneration. The objective of this study was to assess whether elevated extracellular zinc has a direct effect on retinal pigment epithelial cells (RPE), by examining the phenotype and molecular characteristics of increased extracellular zinc on human primary RPE cells. Monolayers of human foetal primary RPE cells were grown on culture inserts and maintained in medium supplemented with increasing total concentrations of zinc (0, 75, 100, 125 and 150 μM) for up to 4 weeks. Changes in cell viability and differentiation as well as expression and secretion of proteins were investigated. RPE cells developed a confluent monolayer with cobblestone morphology and transepithelial resistance (TER) >200 Ω*cm2within 4 weeks. There was a zinc concentration-dependent increase in TER and pigmentation, with the largest effects being achieved by the addition of 125 μM zinc to the culture medium, corresponding to 3.4 nM available (free) zinc levels. The cells responded to addition of zinc by significantly increasing the expression of Retinoid Isomerohydrolase (RPE65) gene; cell pigmentation; Premelanosome Protein (PMEL17) immunoreactivity; and secretion of proteins including Apolipoprotein E (APOE), Complement Factor H (CFH), and High-Temperature Requirement A Serine Peptidase 1 (HTRA1) without an effect on cell viability. This study shows that elevated extracellular zinc levels have a significant and direct effect on differentiation and function of the RPE cells in culture, which may explain, at least in part, the positive effects seen in clinical settings. The results also highlight that determining and controlling of available, as opposed to total added, zinc will be essential to be able to compare results obtained in different laboratories.
... Current treatment for AMD consists of AREDS vitamins for dry AMD, which according to recent work may slow disease progression by modulating complement activity (73) or suppressing complement-mediated endothelial cell activation (74), and intravitreal anti-VEGF antibodies for neovascular AMD. Directly targeting the complement system promises to provide exciting new therapeutic options with the potential to slow AMD progression before the development of RPE atrophy or CNV (75). ...
Age-relatedmacular degeneration (AMD) is amajor cause of visual impairment that affects the central retina. Genome wide association studies and candidate gene screens have identifiedmembers of the complement pathway as contributing to the risk of AMD. In this review, we discuss the complement system, its importance in retinal development and normal physiology, how its dysregulation may contribute to disease, and how itmight be targeted to prevent damage to the aging choriocapillaris in AMD. © The Author 2017. Published by Oxford University Press. All rights reserved.
