TY - JOUR. T1 - Redistribution of Na-K-ATPase in the dystrophic rat retinal pigment epithelium. AU - Caldwell, Ruth B.. AU - McLaughlin, Barbara J.. N1 - Copyright: Copyright 2007 Elsevier B.V., All rights reserved.. PY - 1984/12. Y1 - 1984/12. N2 - Our previous studies have shown that a breakdown in tight junctions in the dystrophic retinal pigment epithelium (RPE) of Royal College of Surgeons rats is accompanied by changes in intramembrane structure which suggest a redistribution of intramembrane particles. We have now investigated, using the p-nitrophenyl phosphate technique, the possibility that a specific membrane protein, Na-K-ATPase, is redistributed as tight junctions break down in the dystrophic RPE. In the normal RPE, Na-K-ATPase activity is restricted to the apical membrane. Junctional membranes and membranes around phagosomes are free of enzyme activity, suggesting a segregation of the transport enzyme from the Junctional and phagocytic membrane. In the dystrophic RPE, prior to ...
TY - JOUR. T1 - Repigmentation of human retinal pigment epithelial cells in vitro. AU - Boulton, Mike. AU - Marshall, John. PY - 1985/8. Y1 - 1985/8. N2 - Cultured human retinal pigment epithelial (RPE) cells readily ingested both melanin and lipofuscin isolated from human RPE cells. Up to 7 days post-challenge ingested granules demonstrated no evidence of lysis or aggregation within secondary lysosomes. When cultures containing ingested melanin and lipofuscin were subcultured the cells gradually depigmented due to a redistribution of pigment granules amongst daughter cells. Quantitative analysis demonstrated that the accumulation of both types of granule was linear over a 24 hr challenge period. This study reports a technique of artificially repigmenting cultured human RPE cells and thus offers the potential for in vitro investigations of the role of these inclusions in various dynamic aspects of cellular metabolism.. AB - Cultured human retinal pigment epithelial (RPE) cells readily ingested ...
TY - JOUR. T1 - Genotoxic effects of carotenoid breakdown products in human retinal pigment epithelial cells. AU - Kalariya, Nilesh M.. AU - Ramana, Kota. AU - Srivastava, Satish. AU - Van Kuijk, Frederik J G M. PY - 2009. Y1 - 2009. N2 - Purpose: To investigate the genotoxic effects of lutein (LBP) and β -carotene breakdown products (β -apo-8-carotenal, BA8C) and the preventive role of GSH in human retinal pigment epithelial cells (ARPE-19). Methods: LBP- and BA8C-induced DNA damage in human retinal pigment epithelial cells (ARPE-19) was determined by comet assay. The DNA damage was quantified by the image analysis system using Comet Score™ software. ARPE-19 cell viability was determined by CellTiter 96 AQueous one-solution cell proliferation assay kit. Intracellular GSH levels were measured by Ellmans reagent. Results: Incubation of serum-starved ARPE-19 cells with LBP and BA8C caused significant DNA damage in a dose- and time-dependent manner. The DNA damage and cell death incurred by ...
PURPOSE: To characterize glutathione (GSH) transport by cultured human retinal pigment epithelial (HRPE) cells. METHODS: Cultured HRPE cells were pretreated with acivicin for GSH efflux and with buthionine sulfoximine for GSH uptake to prevent the breakdown and resynthesis of GSH. Efflux was measured by the linear rate of accumulation of GSH in the supernatant; uptake was measured using [35S] GSH plus varying concentrations of GSH. Molecular forms were verified by high-performance liquid chromatography. HRPE cell mRNA was probed for the presence of the two recently cloned rat sinusoidal and canalicular GSH transporters, (RsGshT and RcGshT), by Northern blot analysis. RESULTS: Glutathione efflux was temperature dependent (undetectable at 4 degrees C), and its averaged 23 +/- 3.3 pmol/10(6) cells/minute or 10% of the total GSH effluxed per hour (total cell GSH = 13.6 +/- 1.5 nmol/10(6) cells). Efflux was not influenced by dithiothreitol or sulfobromophthalein-reduced GSH adduct, agents known to ...
Purpose: : To investigate the in vitro effects of tobacco-specific n- nitrosamines (TSNA); (N-Nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) which are the major components of cigarette smoke on human retinal pigment epithelial cells. Methods: : Human ARPE-19 cultures were exposed to varying concentrations of NNN and NNK (1mM, 100µM, 10µM, 1 µM) in DMEM/F12 medium for 24 and 48 hours. MTT cell proliferation assays were performed to find a non toxic dose that would not kill the cells within the 24-48 hour period. For both NNN and NNK a 10µM dose of 24 hours was chosen to carry out the rest of the experiments. Total cell protein extracts were analyzed for the presence of OGG1, a DNA repair enzyme and VEGF. Live cells were stained with Hoechst and Mitotracker Green to visualize the nucleus and mitochondrial mass respectively using a confocal microscope. Cells were also labeled for anti- VEGFR2 and imaged using a confocal microscope. Comet assay was performed on ...
TY - JOUR. T1 - TNF-α mediates PKCδ/JNK1/2/c-Jun-dependent monocyte adhesion via ICAM-1 induction in human retinal pigment epithelial cells. AU - Lee, I-Ta. AU - Liu, Shiau Wen. AU - Chi, Pei Ling. AU - Lin, Chih Chung. AU - Hsiao, Li Der. AU - Yang, Chuen Mao. PY - 2015/2/12. Y1 - 2015/2/12. N2 - Retinal inflammatory diseases induced by cytokines, such as tumor necrosis factor-α(TNF-α) are associated with an up-regulation of intercellular adhesion molecule-1 (ICAM-1) in the retinal pigment epithelial cells (RPECs). Retinal pigment epithelium (RPE) is a monolayer of epithelial cells that forms the outer blood-retinal barrier in the posterior segment of the eye, and is also implicated in the pathology of, such as neovascularization in agerelated macular degeneration (AMD). However, the detailed mechanisms of TNF-α-induced ICAM-1 expression are largely unclear in human RPECs. We demonstrated that in RPECs, TNF-α could induce ICAM-1 protein and mRNA expression and promoter activity, and ...
The goal of the present study was to determine whether treatment with cigarette smoke extract (CSE) induces cell loss, cellular senescence, and extracellular matrix (ECM) synthesis in primary human retinal pigment epithelial (RPE) cells. Primary cultured human RPE cells were exposed to 2, 4, 8, and 12% of CSE concentration for 24 hours. Cell loss was detected by cell viability assay. Lipid peroxidation was assessed by loss of cis-parinaric acid (PNA) fluorescence. Senescence-associated ß-galactosidase (SA-ß-Gal) activity was detected by histochemical staining. Expression of apolipoprotein J (Apo J), connective tissue growth factor (CTGF), fibronectin, and laminin were examined by real-time PCR, western blot, or ELISA experiments. The results showed that exposure of cells to 12% of CSE concentration induced cell death, while treatment of cells with 2, 4, and 8% CSE increased lipid peroxidation. Exposure to 8% of CSE markedly increased the number of SA-ß-Gal positive cells to up to 82%, and the mRNA
TY - JOUR. T1 - L-carnitine protects human retinal pigment epithelial cells from oxidative damage. AU - Shamsi, Farrukh A.. AU - Chaudhry, Imtiaz A.. AU - Boulton, Mike E.. AU - Al-Rajhi, Ali A.. PY - 2007/6/1. Y1 - 2007/6/1. N2 - Purpose: To determine the efficacy of L-carnitine (LC) against oxidative changes in human retinal pigment epithelium (RPE) cells. Methods: The RPE cells from human donor eyes were cultured in Hams F-10 medium. The effect of LC on H2O2-induced morphologic changes in the RPE cells was analyzed by light microscopy. Reduction in cell death after the impact of LC treatment on H2O2-treated cells was analyzed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide] assays. In addition, the effect of H2O2 on the activity of RPE-antioxidant enzymes, glutathione (GSH) and superoxide dismutase (SOD), and LC-induced protection was also determined. Results: LC protected the RPE cells by inhibiting the peroxide-induced cytopathic effect from 50% to 10%. Nuclear ...
TY - JOUR. T1 - Proliferation of retinal pigment epithelial cells induced by (R, R)-XY-10 and (S, S)-XY-10 and their action mechanisms. AU - Cheng, Yu Wen. AU - Wang, Yu Liang. AU - Zhang, Yi Hua. AU - Peng, Si Xun. AU - Chiou, George C.Y.. PY - 2009/10/22. Y1 - 2009/10/22. N2 - • AIM: To investigate the mechanism of proliferation effect induced by (R, R)-XY-10 and (S, S)-XY-10 on retinal pigmented epithelial cells (ARPE-19). • METHODS: Human retinal pigmented epithelial cells (ARPE-19) and human umbilical vein endothelial cells (HUVECs) were used to investigate the effect of (R, R)-XY-10 and (S, S)-XY-10 on cell growth, and their mechanisms of proliferative action by using ERKinverted commas AKTinverted commas PI3Kinverted commas Protein kinase C (PKC)and Nitric oxide synthase (NOS) inhibitors. RESULTS: (R, R)-XY-10 and (S, S)-XY-10 dose-dependently increased ARPE-19 cell proliferation, but not on HUVECs. When treated with proliferative inhibitors, H7 (5μ mol/L)inverted commas hypericin ...
TY - JOUR. T1 - Age-related susceptibility to apoptosis in human retinal pigment epithelial cells is triggered by disruption of p53-Mdm2 association.. AU - Bhattacharya, Sujoy. AU - Chaum, Edward. AU - Johnson, Dianna A.. AU - Johnson, Leonard R.. PY - 2012/1/1. Y1 - 2012/1/1. N2 - Relatively little is known about the contribution of p53/Mdm2 pathway in apoptosis of retinal pigment epithelial (RPE) cells or its possible link to dysfunction of aging RPE or to related blinding disorders such as age-related macular degeneration (AMD). Age-associated changes in p53 activation were evaluated in primary RPE cultures from human donor eyes of various ages. Apoptosis was evaluated by activation of caspases and DNA fragmentation. Gene-specific small interfering RNA was used to knock down expression of p53. We observed that the basal rate of p53-dependent apoptosis increased in an age-dependent manner in human RPE. The age-dependent increase in apoptosis was linked to alterations in several aspects of the ...
In the present study, we investigated the effects of blue light filtering on the secretion profile of proangiogenic cytokines by RPE cells. To the best of our knowledge, this is the first study to demonstrate that following light exposure, angiogenin secretion by RPE cells is decreased, and this decrease is abrogated with a blue light filter. We also demonstrated that, although not significant, this trend is maintained when RPE cells are grown under hypoxic conditions and when pre-treated with lutein.. Although the etiology of AMD is not well understood, there is strong evidence indicating that retinal hypoxia plays a significant role in retinal neovascularization [21, 22]. On the other hand, lutein-containing supplements have been found to be beneficial and protective in slowing the progression of AMD [23-26]. We therefore sought to determine whether the effects of blue light filtering are maintained when RPE cells are exposed to hypoxic conditions or when pre-treated with lutein. We focused ...
1. J. R. Sparrrow, D. Hicks, and C. P. Hamel, The retinal pigment epithelium in health and disease, Curr. Mol. Med. 10(9), 802-823 (2010). [CrossRef] 2. O. Strauss, The retinal pigment epithelium in visual function, Physiol. Rev. 85(3), 845-881 (2005). [CrossRef] 3. T. Ach, C. Huisingh, G. McGwin Jr, J. D. Messinger, T. Zhang, M. J. Bentley, D. B. Gutierrez, Z. Ablonczy, R. T. Smith, K. R. Sloan, and C. A. Curcio, Quantitative autofluorescence and cell density maps of the human retinal pigment epithelium, Invest. Ophthalmol. Visual Sci. 55(8), 4832-4841 (2014). [CrossRef] 4. J. A. Gambril, K. R. Sloan, T. A. Swain, C. Huisingh, A. V. Zarubina, J. D. Messinger, T. Ach, and C. A. Curcio, Quantifying retinal pigment epithelium dysmorphia and loss of histologic autofluorescence in age-related macular degeneration, Invest. Ophthalmol. Visual Sci. 60(7), 2481-2493 (2019). [CrossRef] 5. S. Panda-Jonas, J. B. Jonas, and M. Jakobczyk-Zmija, Retinal pigment epithelial cell count, distribution, ...
A primary function of cadherins is to regulate cell adhesion. Here, we demonstrate a broader function of cadherins in the differentiation of specialized epithelial cell phenotypes. In situ, the rat retinal pigment epithelium (RPE) forms cell-cell contacts within its monolayer, and at the apical membrane with the neural retina; Na+, K(+)-ATPase and the membrane cytoskeleton are restricted to the apical membrane. In vitro, RPE cells (RPE-J cell line) express an endogenous cadherin, form adherens junctions and a tight monolayer, but Na+,K(+)-ATPase is localized to both apical and basal-lateral membranes. Expression of E-cadherin in RPE-J cells results in restriction and accumulation of both Na+,K(+)-ATPase and the membrane cytoskeleton at the lateral membrane; these changes correlate with the synthesis of a different ankyrin isoform. In contrast to both RPE in situ and RPE-J cells that do not form desmosomes, E-cadherin expression in RPE-J cells induces accumulation of desmoglein mRNA, and assembly ...
Choroidal neovascularization (CNV) is the most severe form of age-related macular degeneration (AMD), which causes rapid visual loss. Transplantation of cultured retinal pigment epithelium (RPE) cell sheet by tissue engineering is a possible approach
We showed previously that confluent ARPE-19 cells grown on different matrices had different transcriptional profiles from native RPE, and that cells grown on plastic had the closest transcriptome to native RPE.2 To improve the transcriptional proximity of ARPE-19 cells grown on plastic to native RPE, we varied the culture conditions and evaluated global expression trends, a more informative benchmark than individual gene expression. With this end point, CSW and DSW cells were most similar to native RPE. While each culture condition preserved the expression of the most abundant genes, significant transcriptional differences exist between native and cultured cells including the number of genes on the array that were expressed and not expressed, the number and function of differentially expressed genes, and the number of expressed low abundance genes. Our results suggest that the global expression profiles can be improved by varying the culture conditions, but significant widespread differences ...
Methods In three primary RPE cell cultures (from three donor eyes) and in the human RPE cell line ARPE-19, FcRn and beta-2-microglobulin (β2M) mRNA levels were determined by real-time quantitative PCR. FcRn protein expression was analysed by western blot studies. Stimulation experiments were performed with recombinant human tumour necrosis factor (TNF)-α and interferon (IFN)-γ. HT-29, THP-1 and HeLa cell lines were used as FcRn positive and negative non-ocular controls, respectively. ...
Research resource: nuclear receptor atlas of human retinal pigment epithelial cells: potential relevance to age-related macular degeneration.
Human Retinal Pigment Epithelial Cell Lysate https://www.sciencepro.com.br/produtos/sc-6546 https://www.sciencepro.com.br/@@site-logo/logo-novo.png ...
TY - JOUR. T1 - The expression of C1 inhibitor (C1INH) in macrophages is upregulated by retinal pigment epithelial cells - implication in subretinal immune privilege in the aging eye. AU - Luo, Chang. AU - Zhao, Jiawu. AU - Chen, Mei. AU - Xu, Heping. PY - 2018/6/13. Y1 - 2018/6/13. N2 - Age-related para-inflammation in the retina-choroidal interface is featured by low-levels of complement activation and subretinal macrophage accumulation. This study aimed to understand how complement expression in macrophages is regulated by retinal pigment epithelium (RPE). Bone marrow-derived macrophages (BMDMs) and RPE cells were cultured from 8-10 weeks old C57BL/6J mice. The BMDMs were co-cultured with normal RPE, or oxidized photoreceptor outer segment (oxPOS) or TNF-α pre-treated RPE, or apoptotic RPE, or RPE-choroid eyecups. Macrophages were then isolated and processed for real-time RT-PCR. The expression of complement inhibitor C1INH in BMDMs was significantly upregulated by RPE and RPE-choroid ...
The retinal pigment epithelium (RPE) is constantly exposed to external injuries which lead to degeneration, dysfunction or loss of RPE cells. The balance between RPE cells death and proliferation may be responsible for several diseases of the underlying retina, including age-related macular degeneration (AMD) and proliferative vitreoretinopathy (PVR). Signaling pathways able to control cells proliferation or death usually involve the MAPK (mitogen-activated protein kinases) pathways, which modulate the activity of transcription factors by phosphorylation. UV exposure induces DNA breakdown and causes cellular damage through the production of reactive oxygen species (ROS) leading to programmed cell death. In this study, human retinal pigment epithelial cells ARPE19 were exposed to 100 J/m(2) stop of UV-C and MAPK pathways were studied. We first showed the expression of the three major MAPK pathways. Then we showed that activator protein-1 (AP-1) was activated through phosphorylation of cJun and ...
Dept of Biochemistry, Cell Biology was started in a small way in the year 1985 . Active research was started in 1991 by Prof. S. Ramakrishnan and Dr. K. N. Sulochana into Ocular Biochemistry. The extensive areas of research includes, cataract, Eales disease, Diabetic Retinopathy, pathways of homocysteine and proteoglycan, novel protein isolation, use of amino acid as antiglycating substances to mitigate diabetic complication were the focus of the lab.. Later Dr. N. Angayarkanni since 2002 has been working in primary cultures of Bovine retinal pigment epithelium, retinal capillary Endothelial and pericytes focussing on ECM changes in the vitreo-retinal pathologies apart from establisbing proteomics. Current Focus is on drug development for the treatment of ocular angiogenesis, alterations in metabolic pathways leading to diseases, structural function studies of proteins, protein-protein interactions, clinical proteomics, lipidomics, toxicology ...
Retinal pigment epithelial cells (RPE) stably expressed human CXCR4 when transduced with N-terminal FLAG or N-terminal FLAG and C-terminal MYC
This project proposes a multidisciplinary approach for studying the decline of vision with ageing. It focuses on a specialised monolayer of cells, the retinal pigment epithelium (RPE), which comes in direct contact with the neuroretina and separates it from the vasculature at the back of the eye. RPE cells ensure rods and cones in the retina are renewed and supplied with nutrients daily throughout life. Due to the intense metabolic rate they sustain, as well as the high levels of light and oxygen they are exposed to, RPE cells are prone to high oxidative stress. Although they are equipped to protect themselves against this stress, their protective antioxidant mechanisms decline with ageing and this contributes to the impairment of the overall RPE functions which in turn leads to gradual visual impairment and even blindness.. Understanding the mechanisms through which ageing and oxidative stress lead to changes in normal RPE physiology is essential for developing preventative and therapeutic ...
TY - JOUR. T1 - Ascorbate suppresses VEGF expression in retinal pigment epithelial cells. AU - Sant, David W.. AU - Camarena, Vladimir. AU - Mustafi, Sushmita. AU - Li, Yiwen. AU - Wilkes, Zachary. AU - van Booven, Derek. AU - Wen, Rong. AU - Wang, Gaofeng. PY - 2018/7/1. Y1 - 2018/7/1. N2 - PURPOSE. To investigate the impact of ascorbate, via DNA hydroxymethylation, on VEGF expression in retinal pigment epithelial (RPE) cells. METHODS. Dot-blot and hydroxymethylated DNA immunoprecipitation sequencing were applied to evaluate the impact of ascorbate on DNA hydroxymethylation in ARPE-19 cells. RNA sequencing (RNA-seq) was carried out to analyze the transcriptome. Quantitative RT-PCR and ELISA were conducted to examine the transcription and secretion of VEGF from cultured cells. Primary human fetal RPE cells and RPE-J cells were used to verify the effect of ascorbate on VEGF expression. ELISA was used to measure VEGF in the vitreous humor of Gulo-/-mice, which, like humans, cannot synthesize ...
ATCC hTERT immortalized RPE cell lines have an extended lifespan, undergo terminal differentiation, express RPE associated proteins, and are karyotypically, morphologically, and phenotypically similar to the primary parent cells.
ATCC hTERT immortalized RPE cell lines have an extended lifespan, undergo terminal differentiation, express RPE associated proteins, and are karyotypically, morphologically, and phenotypically similar to the primary parent cells.
Time lapse series of cell growth and division in cultured hTERT-RPE1 cells (telomerase immortalized human retinal pigment epithelium) using differenti...
Age-related macular degeneration (AMD) is a leading cause of worldwide blindness in the elderly. It is a bilateral ocular condition that impairs the central retina known as the macula. The macula accounts for the majority of daytime, color vision in humans. Thus, lesions in the macula have a major impact on human vision. Previous studies have suggested that oxidative stress to certain ocular cells may contribute to the development of AMD. Oxidative stress occurs when reactive oxygen species (ROS) interact with protein and DNA to modify their functions. In this study, Aryan et al used hydrogen peroxide, a highly reactive compound, to induce oxidative stress in human retinal pigment epithelial cells, a type of ocular cell which provides nourishment for the human retina. Oxidative stress resulted in a profound influence on advancing the senescence (functional deterioration) of these cells and inhibiting their proliferation. These results strongly suggest that oxidative stress plays a role in the ...
Hyperspectral AF images (hypercubes) were captured from 66, 40X fields in 11 RPE/BrM flat mounts from human donor eyes using techniques described in detail in the abstract submitted by K. Agarwal. Briefly, for each 40X field, the hypercube has the two spatial dimensions of the field, and at each spatial point the photon counts recorded at each wavelength, hence the third or spectral dimension. For reproducible quantification of these data, exposure times were calibrated so that photon counts per spectral channel fell within the 12-bit linear range of the detector and then were offset by the dark current. Scaled counts-per-second were determined by exposure time (Eqn. 1) and calibrated to a standard fluorescent reference (courtesy of F Delori) to correct for any variation in power of the excitation light, yielding quantified hypercubes with units of photon counts per second at each point and wavelength.. Results ...
In silico pathway, gene ontology, and system-level network comparisons of EBOV-infected and mock-infected ARPE-19 cell transcriptomic profiles all revealed that EBOV-infected human retinal pigment epithelial cells generated a robust type I IFN response. Consistent with these results, 28% of significantly upregulated transcripts were identified as type I IFN-responsive in the Interferome database of IFN-regulated genes.27 Although the type I IFN response is a critical innate immune defense against viral infection, this result was quite unexpected; EBOV causes severe and accelerated pathology, because it prevents the type I IFN response in other human host cells, including the mononuclear phagocyte populations that are its early targets.37 The major type I IFNs are IFN-α and IFN-β: IFN-β may be more important for the response to EBOV, because treatment with recombinant IFN-β, but not IFN-α, prolongs survival of infected macaques.38 Both IFN-α and IFN-β signal via the IFN-α/β receptor, ...
In silico pathway, gene ontology, and system-level network comparisons of EBOV-infected and mock-infected ARPE-19 cell transcriptomic profiles all revealed that EBOV-infected human retinal pigment epithelial cells generated a robust type I IFN response. Consistent with these results, 28% of significantly upregulated transcripts were identified as type I IFN-responsive in the Interferome database of IFN-regulated genes.27 Although the type I IFN response is a critical innate immune defense against viral infection, this result was quite unexpected; EBOV causes severe and accelerated pathology, because it prevents the type I IFN response in other human host cells, including the mononuclear phagocyte populations that are its early targets.37 The major type I IFNs are IFN-α and IFN-β: IFN-β may be more important for the response to EBOV, because treatment with recombinant IFN-β, but not IFN-α, prolongs survival of infected macaques.38 Both IFN-α and IFN-β signal via the IFN-α/β receptor, ...
PURPOSE: To locate the mildest and/or earliest changes in the retina and/or choroid in Sveinsson chorioretinal atrophy (SCRA), using more advanced techniques than previous studies. METHODS: We used fundus photography, intravenous fluorescein angiography (IVFA) enhanced ocular coherence tomography (OCT) scans, microperimetry and multifocal electroretinography (mfERG) in an attempt to locate the mildest changes in SCRA. Eight patients with SCRA were examined. To improve the resolution of OCT scans, several consecutive recorded B-scans were retrieved for each location of interest. The scans were processed off-line with an averaging algorithm developed to maximally reduce laser speckle (noise). Static microperimetry was performed using the Rodenstock scanning laser ophthalmoscope (SLO). RESULTS: Biomicroscopy and fundus photographs disclosed an apparent thinning of the retinal pigment epithelium (RPE) in the areas minimally affected, where possible changes in the transparent sensory retina were not ...
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The selective damage of the retinal pigment epithelium (RPE) is a new treatment method for several retinal diseases. By applying a train of microsecond(s) laser pulses it is possible to selectively damage these cells and simultaneously spare the adjacent photoreceptor and neural tissue. Due to the ophthalmologic invisibility of the RPE cell damage we investigate an optoacoustic (OA) control system to monitor the RPE cell damage. Setup: The irradiation was performed with a frequency doubled Nd:YLF laser by applying a train of +s laser pulses. In vitro, the OA transients were received by an ultrasonic broadband transducer. During treatment an OA contact lens with embedded transducer was used. In vitro: Freshly enucleated porcine RPE samples with CalceinAM as life/death staining were used. Below RPE cell damage threshold a classic thermoelastic transient was found. Above cell damage threshold the OA transient differs form pulse to pulse. This can be explained by microbubble formation around the ...
The retinal pigment epithelium (RPE)1 is a highly specialized derivative of the embryonic neural tube that lies with its apical surface in intimate contact with the light-sensitive cells of the retina (Zinn and Marmor, 1979), performing critical transport, barrier, and phagocytic support functions for the neural retina. These functions of RPE cells require a characteristic apical distribution of certain proteins that are usually found on the basolateral membrane in other epithelia. For example, apical Na,K-ATPase provides a high Na+ environment appropriate for photoreceptor function (Bok, 1982; Okami et al., 1990; Gundersen et al., 1991; Gallemore et al., 1997; Miller and Steinberg, 1977; Rizzolo, 1997; Zhao et al., 1997). The apical localization of the neural cell adhesion molecule N-CAM-140 in RPE (Gundersen et al., 1993), which overrides a dominant basolateral signal in the cytoplasmic domain recognized by MDCK cells (Powell et al., 1991; Le Gall et al., 1997), is presumably required to ...
TY - JOUR. T1 - The effects of zinc supplementation on primary human retinal pigment epithelium. AU - Pao, Po-Jung. AU - Emri, Eszter. AU - Abdirahman, Safiya Bishar. AU - Soorma, Talha. AU - Zeng, Hui-Hui. AU - Hauck, Stefanie M. AU - Thompson, Richard B. AU - Lengyel, Imre. N1 - Copyright © 2018 Elsevier GmbH. All rights reserved.. PY - 2018/3/1. Y1 - 2018/3/1. N2 - 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 ...
7-MX has an effect on eye development and myopia [4]. The present study showed that 7-MX barely suppresses the growth of human RPE cells cultured in vitro, but 7-MX could statistically significantly inhibit the expression of ADORA1, ADORA2A, and ADORA2B in RPE cells in short-term treatment. RPE plays a critical role in relaying retinal growth signals to the choroids and sclera [23]. One of the most important mechanisms of myopia formation is that the visual signal concerned with myopia transfers from the neural retinal to the RPE, where fluid exchange transits molecular signals from the retinal and choroid layers to the sclera, followed by scleral remodeling [8]. As confluent monolayers of adult human RPE cultures exhibit characteristics of native RPE [24], it would have been more relevant for our study. 7-MX is a metabolite of caffeine and theobromine shown to work against myopia [4,8,9]. The peak serum concentration after an oral dose of 400 mg 7-MX in adults is around 20 μmol/l with a ...
TY - JOUR. T1 - Expression of heme oxygenase-1 is repressed by interferon-γ and induced by hypoxia in human retinal pigment epithelial cells. AU - Udono-Fujimori, Reiko. AU - Takahashi, Kazuhiro. AU - Takeda, Kazuhisa. AU - Furuyama, Kazumichi. AU - Kaneko, Kiriko. AU - Takahashi, Shigeru. AU - Tamai, Makoto. AU - Shibahara, Shigeki. N1 - Copyright: Copyright 2008 Elsevier B.V., All rights reserved.. PY - 2004/7. Y1 - 2004/7. N2 - The retinal pigment epithelium (RPE) is essential for maintenance of photoreceptors and normally functions under conditions enriched with reactive oxygen species. RPE therefore expresses various defense enzymes against oxidative stress, including heme oxygenase-1 (HO-1). HO-1 catalyzes heme breakdown to release iron, carbon monoxide, and biliverdin, which is reduced to bilirubin, a potent radical scavenger. HO-1 expression is induced by various environmental factors, which has been established as a defense mechanism. To explore the hypothesis that the expression level ...
0053] Non-limiting examples of suitable magenta or red or violet organic pigments include C.I. Pigment Red 1, C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 4, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 8, C.I. Pigment Red 9, C.I. Pigment Red 10, C.I. Pigment Red 11, C.I. Pigment Red 12, C.I. Pigment Red 14, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 17, C.I. Pigment Red 18, C.I. Pigment Red 19, C.I. Pigment Red 21, C.I. Pigment Red 22, C.I. Pigment Red 23, C.I. Pigment Red 30, C.I. Pigment Red 31, C.I. Pigment Red 32, C.I. Pigment Red 37, C.I. Pigment Red 38, C.I. Pigment Red 40, C.I. Pigment Red 41, C.I. Pigment Red 42, C.I. Pigment Red 48(Ca), C.I. Pigment Red 48(Mn), C.I. Pigment Red 57(Ca), C.I. Pigment Red 57:1, C.I. Pigment Red 88, C.I. Pigment Red 112, C.I. Pigment Red 114, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 144, C.I. Pigment Red 146, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 166, ...
TY - JOUR. T1 - Retinal pigment epithelial cells from dystrophic rats form normal tight junctions in vitro. AU - Chang, Chih Wei. AU - Defoe, Dennis M.. AU - Caldwell, Ruth B. PY - 1997/2/6. Y1 - 1997/2/6. N2 - Purpose. In the genetically defective Royal College of Surgeons (RCS) rat model for retinal degeneration, a breakdown occurs in the retinal pigment epithelial (RPE) cell tight junctions just as the photoreceptors begin to degenerate. These experiments sought to determine the impact of the RPE genetic defect on this alteration in the RPE cell tight junctions. Methods. Retinal pigment epithelial cell cultures prepared from RCS and control rats were treated with hormonally defined medium (HDM), base medium conditioned by RCS or control retinas, or unconditioned base medium. The tight junctions formed by these cultures were assayed functionally by measuring transepithelial electrical resistance and permeability. Junction structure was evaluated by immunolocalization of the tight junction ...
A model demonstrating the place of the GPR143 gene in the pathogenesis of ocular albinism type 1. The latter shows the interactions between GPR143 and the different genes responsible for melanogenesis as well as growth factors such as SERPINF1 and VEGF in melanocytes or the retinal pigment epithelium ...
The epigenetic plasticity of amphibian retinal pigment epithelium (RPE) allows them to regenerate the entire retina, a trait known to be absent in mammals. In this study, we investigated the epigenetic plasticity of adult murine RPE to identify possible mechanisms that prevent mammalian RPE from reg …
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TY - JOUR. T1 - Synthesis of complement factor H by retinal pigment epithelial cells is down-regulated by oxidized photoreceptor outer segments. AU - Chen, Mei. AU - Forrester, John Vincent. AU - Xu, Heping. PY - 2007/4. Y1 - 2007/4. N2 - Complement activation is thought to be involved in the pathogenesis of age-related macular degeneration (AMD), in part because certain gene polymorphisms in complement factor H (CFH), an important regulator of the alternative complement activation pathway, are high risk factors for AMD. How CFH is regulated locally at the retina/choroid interface and how this contributes to AMD development remain unknown. In the present study, we have confirmed that CFH was detectable by immunohistochemistry in the choroid, and at low levels in the RPE cell and interphotoreceptor matrix, but appeared to be concentrated in dense patches in Bruchs membrane. In vitro, cultured human and mouse RPE cells expressed high levels of CFH as evidenced by immunohistochemistry and western ...
The retinoid visual cycle is a sequence of metabolic and transport reactions of retinoids in the retina and the retinal pigment epithelium (RPE). Many proteins are involved in this cycle and play critical roles in the generation of II-cis retinal, the chromophore that binds opsin to form the visual pigments. Mutations of these proteins cause eye diseases that can eventually lead to blindness. RPE65 and LRA T are essential proteins involved in the visual dark cycle to regenerate visual pigments, while RDHIO is thought to produce all-trans retinal, the substrate for the retinal G protein-coupled receptor (RGR) in the photic cycle to regenerate visual pigments. This research is focused on studying the visual cycle proteins (RPE65, LRAT and RDHIO) and tested the hypothesis that the HEK293 cells can be used as an in vitro model to study visual vitamin A metabolism. The protein RPE65 was purified from native bovine RPE and the molecular mass of this protein was determined. Retinoic acid (RA) was found ...
The blood-retinal barrier, or the BRB, is part of the blood-ocular barrier that consists of cells that are joined tightly together to prevent certain substances from entering the tissue of the retina. It consists of non-fenestrated capillaries of the retinal circulation and tight-junctions between retinal epithelial cells preventing passage of large molecules from choriocapillaris into the retina. The blood retinal barrier has two components: the retinal vascular endothelium and the retinal pigment epithelium. Retinal blood vessels that are similar to cerebral blood vessels maintain the inner blood-ocular barrier. This physiological barrier comprises a single layer of non-fenestrated endothelial cells, which have tight junctions. These junctions are impervious to tracer, so many substances can affect the metabolism of the eyeball. The retinal pigment epithelium maintains the outer blood-retinal barrier. Diabetic retinopathy, eye damage that frequently occurs as a result of diabetes, is related ...
congenital hypertrophy of the retinal pigment epithelium answers are found in the Tabers Medical Dictionary powered by Unbound Medicine. Available for iPhone, iPad, Android, and Web.
three experiments with three different cell cultures (*P,0.05). Co, control. doi:10.1371/journal.pone.0048501.gEffects of Smoke in RPEan accelerated ageing process in AMD [24,46,47,48]. We have previously shown that sublethal concentrations of hydrogen peroxide induced senescence-associated ?Galactosidase (SA- al) activity in primary cultured RPE cells [29]. In the experiments of the current study, treatment of primary human RPE cultures with CSE could significantly increase the proportion of SA-?Gal positive cells. Positive staining of SA-?Gal has also been detected in vitro in late passage RPE cultures [49,50] and in vivo in the RPE cells of old primate eyes [51]. In human RPE cells, an increased expression of SA-?Gal staining could be triggered by mild hyperoxia-mediated ROS release [52]. Furthermore, cellular s.And can induce RPE cell death [42]. In our experiments, treatment of primary human RPE cells with 2, 4, and 8 of cigarette smoke extract (CSE) had no significant effects onFigure 5. ...
PURPOSE: To provide long-term (| or =5 years) follow-up data on patients who had previously undergone macular retinal pigment epithelium (RPE) translocation surgery for choroidal new vessels (CNVs) associated with age-related macular degeneration. DESIGN: Retrospective interventional case series. PARTICIPANTS: Four of 9 patients who originally underwent surgery and whose results were reported after 2 years of follow-up were reviewed again 5 to 6 years after surgery. METHODS: All surviving patients from the original trial were contacted, and those who consented to full ocular examination were called in for review. Examination included best-corrected visual acuity (VA), optical coherence tomography (OCT), fundus autofluorescence, fluorescein angiography (FA), and indocyanine green angiography. MAIN OUTCOME MEASURES: Long-term success of RPE translocation was assessed by VA, imaging, angiography, and maintenance of overlying foveal fixation. Comparisons were made to the original 2-year follow-up data
Elevated inflammatory cytokines contribute to the pathogenesis of various retinal diseases such as diabetic retinopathy, retinal vasculitis and retinitis. However, the underlying mechanism of retinal inflammation remains largely unknown. Recent studies demonstrated that acetylcholinesterase (ACHE) is an inflammatory indicator in central neural system. This study was aimed to dissect the role of ACHE in retinal inflammation, and its mechanism of action. Retinal inflammation was induced by intravitreal injection of tumor necrosis factor-α (TNF-α) in heterozygous ACHE knockout mice (ACHE+/-) and wild type mice (ACHE+/+). Donepezil, a well-known ACHE inhibitor, was administrated by daily gavage. Expression of ACHE and intercellular adherent molecule-1 (ICAM-1), infiltration of CD11b+ inflammatory cells, retinal leukostasis and vascular leakage was determined in both ACHE ± and ACHE+/+ mice. ARPE-19â ¯cells, a human retinal pigment epithelial cell line, were cultured for in vitro assay. ...
The cultured cell collection includes the top differentially expressed genes in 131 human primary and stem cells, purchased from different cell supplying companies, grown and analyzed by BioTime.. Total RNA was extracted from cells, using Qiagen RNeasy mini kits, according to the manufacturers instructions. RNA concentrations were determined using a Beckman DU530 or Nanodrop spectrophotometer and RNA quality was determined by denaturing agarose gel electrophoresis or using an Agilent 2100 bioanalyzer.. Whole-genome expression analysis was carried out using Illumina Human HT-12 v4 BeadArrays (GPL10558). Total RNA was linearly amplified and biotin-labeled, using Illumina TotalPrep kits (Life Technologies, Temecula, CA, USA). The amplified, labeled RNA was quality-controlled using an Agilent 2100 Bioanalyzer. The RNA was then hybridized to Illumina BeadChips, processed, and read using a BeadStation array reader, according to the manufacturers instructions (Illumina, San Diego, CA, USA).. The ...
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Efficient delivery of NF-κB siRNA to human retinal pigment epithelial cells with hyperbranched cationic polysaccharide derivative-based nanoparticles Zhenzhen Liu,1,* Haijun Gong,2,* Rui Zeng,2 Xuan Liang,1 Li-Ming Zhang,1 Liqun Yang,1,* Yuqing Lan2,* 1Institute of Polymer Science, School of Chemistry and Chemical Engineering, Key Laboratory of Designed Synthesis and Application of Polymer Material, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Ophthalmology, Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Abstract: A hyperbranched cationic polysaccharide derivative-mediated small interfering (si)RNA interference strategy was proposed to inhibit nuclear transcription factor-kappa B (NF-
El objetivo de este protocolo es demostrar que el cultivo del pigmento retiniano epitelial (RPE) células en membrana de Bruch humano...
Purpose:In the retina, the balance between pro- and anti-angiogenic factors is critical for angiogenesis control but is also involved in cell survival and maintenance. For instance, the anti-angiogenic factor PEDF is neuroprotective for photoreceptors (PRs) in models of retinal degeneration. We previously reported upregulation of VEGF (24h to 48h post lesion) in the light-damage (LD) model. Furthermore, systemic delivery of PEDF, as well as lentiviral gene transfer of an anti-VEGF antibody rescue PRs from cell death. Studies in vitro show that VEGF induces retinal endothelial cells apoptosis via the alteration of the Akt1/p38 MAPK signalling pathway under hypoxic conditions. Thus, in this study, we investigate the effect of high levels of VEGF on retinal pigmented epithelium (RPE) permeability and molecular targets expression after light-induced PR degeneration. Methods:To characterize the action of VEGF in the retina during the course of LD, we exposed adult Balb/c mice to 5000 lux f
Figure 2. Comparison of the pathology of normal and rdd chicken retinas at 3-4 months. Comparison of normal (A) and rdd (B) retina at 3-4 months of age, both to scale. The rdd retina shows marked atrophy of all layers with virtually complete loss of photoreceptors and replacement by gliosis. GCL = ganglion cell layer, IPL = inner plexiform layer, INL = inner nuclear layer, PRL = photoreceptor layer and RPE = retinal pigment epithelium. Both haematoxylin and eosin at 340x magnification. (C) High power view of the rdd retina showing marked atrophy. Note in particular the complete absence of the outer nuclear layer (usually seen between the inner nuclear and photoreceptor layers). The photoreceptor layer shows loss of photoreceptors, gliosis and prominent clefts above the remnant of the retinal pigment epithelium. GCL = ganglion cell layer, IPL = inner plexiform layer, INL = inner nuclear layer, PRL = photoreceptor layer, RPE = retinal pigment epithelium. Haematoxylin and eosin at 1,800x ...
Choroideremia occurs almost exclusively in males. In childhood, night blindness is the most common first symptom. As the disease progresses there is loss of peripheral vision leading to tunnel vision, and later a loss of central vision. Progression of the disease continues throughout the individuals life, although both the rate and the degree of vision loss vary among those affected, even within the same family.. Vision loss due to choroideremia is caused by degeneration of several layers of cells that are essential to sight. These layers, which line the inside of the back of eyes, are called the choroid, the retinal pigment epithelium and the photoreceptors. The choroid consists of several blood vessel layers that are located between the retina and the sclera (the white of the eye). Choroidal vessels provide the retinal pigment epithelium and photoreceptors with oxygen and nutrients necessary for normal function. The retinal pigment epithelium and the photoreceptors are part of the retina. ...
Advances in the discovery of the causes of monogenic retinal disorders, combined with technologies for the delivery of DNA to the retina, offer enormous opportunities for the treatment of previously untreatable blinding diseases. However, for gene augmentation to be most effective, vectors that have the correct cell-type specificity are needed. While animal models are very useful, they often exhibit differences in retinal cell surface receptors compared to human retina. In this study, we evaluated the use of an ex vivo organotypic explant system to test the transduction efficiency and tropism of 7 different adeno-associated viral type 2 (AAV2) serotypes in human retina and retinal pigment epithelium-choroid: AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9, all driving expression of GFP under control of the cytomegalovirus promoter. After 7 days in culture, we found that AAV2/4 and AAV2/5 are particularly efficient at transducing photoreceptor cells and that AAV2/5 is highly specific ...
Advances in the discovery of the causes of monogenic retinal disorders, combined with technologies for the delivery of DNA to the retina, offer enormous opportunities for the treatment of previously untreatable blinding diseases. However, for gene augmentation to be most effective, vectors that have the correct cell-type specificity are needed. While animal models are very useful, they often exhibit differences in retinal cell surface receptors compared to human retina. In this study, we evaluated the use of an ex vivo organotypic explant system to test the transduction efficiency and tropism of 7 different adeno-associated viral type 2 (AAV2) serotypes in human retina and retinal pigment epithelium-choroid: AAV2/1, AAV2/2, AAV2/4, AAV2/5, AAV2/6, AAV2/8, and AAV2/9, all driving expression of GFP under control of the cytomegalovirus promoter ...
0039]More specifically, examples of the organic pigment include perylene-compound pigments, such as C.I. Pigment Red 179, C.I. Pigment Red 190, C.I. Pigment Red 224, C.I. Pigment Violet 29, or the like; perynone-compound pigments, such as C.I. Pigment Orange 43, C.I. Pigment Red 194 or the like; quinacridone-compound pigments, such as C.I. Pigment Violet 19, C.I. Pigment Violet 42, C.I. Pigment Red 122, C.I. Pigment Red 192, C.I. Pigment Red 202, C.I. Pigment Red 207, C.I. Pigment Red 209 or the like; quinacridonequinone-compound pigments, such as C.I. Pigment Red 206, C.I. Pigment Orange 48, C.I. Pigment Orange 49, or the like; anthraquinone-compound pigments, such as C.I. Pigment Yellow 147 or the like; anthanthrone-compound pigments, such as C.I. Pigment Red 168 or the like; benzimidazolone-compound pigments, such as C.I. Pigment Brown 25, C.I. Pigment Violet 32, C.I. Pigment Yellow 180, C.I. Pigment Yellow 181, C.I. Pigment Orange 36, C.I. Pigment Orange 62, C.I. Pigment Red 185, or the ...
Non-invasive reflectance imaging of the human RPE cell mosaic is demonstrated using a modified confocal adaptive optics scanning light ophthalmoscope (AOSLO). The confocal circular aperture in front of the imaging detector was replaced with a combination of a circular aperture 4 to 16 Airy disks in diameter and an opaque filament, 1 or 3 Airy disks thick. This arrangement reveals the RPE cell mosaic by dramatically attenuating the light backscattered by the photoreceptors. The RPE cell mosaic was visualized in all 7 recruited subjects at multiple retinal locations with varying degrees of contrast and cross-talk from the photoreceptors. Various experimental settings were explored for improving the visualization of the RPE cell boundaries including: pinhole diameter, filament thickness, illumination and imaging pupil apodization, unmatched imaging and illumination focus, wavelength and polarization. None of these offered an obvious path for enhancing image contrast. The demonstrated implementation of dark
For proper function of the retina, the correct proportions of retinal cell types must be generated, they must be organized into cell-specific laminae, and appropriate synaptic connections must be made. To understand the genetic regulation of retinal development, we have analyzed mutations in the mosaic eyes gene that disrupt retinal lamination, the localization of retinal cell divisions to the retinal pigmented epithelial surface and retinal pigmented epithelial development. Although retinal organization is severely disrupted in mosaic eyes mutants, surprisingly, retinal cell differentiation occurs. The positions of dividing cells and neurons in the brain appear normal in mosaic eyes mutants, suggesting that wild-type mosaic eyes function is specifically required for normal retinal development. We demonstrate that mosaic eyes function is required within the retinal pigmented epithelium, rather than in dividing retinal cells. This analysis reveals an interaction between the retinal pigmented ...
Although these experiments use cells that heterologously express CaV1.3 and hBest1, it is very likely that our results are physiologically relevant to RPE cell function. Human RPE cells and the RPE cell line ARPE-19 express CaV α1.3 and β2 subunits (Wimmers et al., 2008). Furthermore, it has been shown recently that hBest1 coimmunoprecipitates with CaVβ subunits from freshly isolated human RPE cells (Strauss et al., 2008). These results suggest that it is likely that the interaction between hBest1 and CaV subunits has an important physiological function and may help resolve the present controversy of whether Best1 is a Cl− channel (Hartzell et al., 2008).. As reviewed in the Introduction, there is strong evidence that bestrophins are Cl− channels (Hartzell et al., 2008), but this idea has been questioned (Marmorstein et al., 2004a,b, 2006; Rosenthal et al., 2005; Marmorstein and Kinnick, 2007). These authors have proposed that hBest1 is not a Cl− channel but rather is a regulator of ...
A Vossius ring appears when iris pigment epithelial cells are compressed against the anterior surface of the lens, depositing a ring of melanin pigment concentric with the pupil.. If the lens capsule is disrupted, a cataract may form immediately. The capsule is thinnest at the posterior pole, the point farthest from the lens epithelial cells. The epithelium of the lens may be stimulated by trauma to form an anterior fibrous plaque just inside the capsule. The lens zonular fibers are points of relative weakness; if they rupture, lens displacement occurs, either partial (subluxation) or complete (luxation). Focal areas of zonular rupture may allow formed vitreous to enter the anterior chamber.. Commotio retinae (Berlin edema) often complicates blunt trauma to the eye. Although it is most prominent in the macula, commotio retinae can affect any portion of the retina. The retinal opacification seen clinically results from disruption in the architecture of the photoreceptor outer segments and the ...