scholarly journals Human iPSC-derived retinal pigment epithelium: a model system for identifying and functionally characterizing causal variants at AMD risk loci

2018 ◽  
Author(s):  
Erin N. Smith ◽  
Agnieszka D’Antonio-Chronowska ◽  
William W. Greenwald ◽  
Victor Borja ◽  
Lana R. Aguiar ◽  
...  
Keyword(s):  
Gene Expression ◽  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Induced Pluripotent Stem Cell ◽  
Age Related Macular Degeneration ◽  
Molecular Characteristics ◽  
Specific Expression ◽  
Age Related ◽  
Causal Variants

SummaryWe evaluate whether human induced pluripotent stem cell-derived retinal pigment epithelium (iPSC-RPE) cells can be used to prioritize and functionally characterize causal variants at age-related macular degeneration (AMD) risk loci. We generated iPSC-RPE from six subjects and show that they have morphological and molecular characteristics similar to native RPE. We generated RNA-seq, ATAC-seq, and H3K27ac ChIP-seq data and observe high similarity in gene expression and enriched transcription factor motif profiles between iPSC-RPE and human fetal-RPE. We performed fine-mapping of AMD risk loci by integrating molecular data from the iPSC-RPE, adult retina, and adult RPE, which identified rs943080 as the probable causal variant at VEGFA. We show that rs943080 is associated with altered chromatin accessibility of a distal ATAC-seq peak, decreased overall gene expression of VEGFA, and allele specific expression of a non-coding transcript. These results provide insight into the mechanism underlying the association of the VEGFA locus with AMD.

scholarly journals Oxidative stress alters transcript localization of disease-causing genes in the retinal pigment epithelium

2021 ◽  
Author(s):  
Tadeusz J Kaczynski ◽  
Elizabeth D Au ◽  
Michael H Farkas
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Induced Pluripotent Stem Cell ◽  
The Body ◽  
Age Related Macular Degeneration ◽  
Nuclear Retention ◽  
Age Related

Nuclear retention is a mechanism whereby RNA transcripts are held in the nucleus to maintain a proper nuclear-to-cytoplasmic balance or as a stockpile for use in responding to stimuli. Many mechanisms are employed to determine whether transcripts are retained or exported to the cytoplasm, though the extent to which tissue- or cell-type, stressors, or disease pathogenesis affect this process remains unclear. As the most biochemically active tissue in the body, the retina must mitigate endogenous and exogenous stressors to maintain cell health and tissue function. Oxidative stress, believed to contribute to the pathogenesis, or progression, of age-related macular degeneration (AMD) and inherited retinal dystrophies (IRDs), is produced both internally from biochemical processes, as well as externally from environmental insult. To evaluate the effect of oxidative stress on transcript localization in the retinal pigment epithelium (RPE), we performed poly-A RNA sequencing on nuclear and cytoplasmic fractions from induced pluripotent stem cell-derived retinal pigment epithelium (iPSC-RPE) cells exposed to hydrogen peroxide, as well as untreated controls. Under normal conditions, the number of mRNA transcripts retained in the nucleus exceeded that found in studies of other tissues. Further, the nuclear-to-cytoplasmic ratio of transcripts is altered following oxidative stress, as is the retention of genes associated with AMD, IRDs, and those important for RPE physiology. These results provide a retention catalog of all expressed mRNA in iPSC-RPE under normal conditions and after exposure to hydrogen peroxide, offering insight into one of the potential roles oxidative stress plays in the progression of visual disorders.

scholarly journals FTO alleviates Aβ1-40 induced retinal pigment epithelium degeneration via PKA/CREB signaling pathway

2020 ◽  
Author(s):  
YiFan Hu ◽  
JieQiong Chen ◽  
JunRan Sun ◽  
YuWei Wang ◽  
PeiRong Huang ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Signaling Pathway ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Amyloid Β ◽  
Age Related Macular Degeneration ◽  
Fundus Photography ◽  
Molecular Characteristics ◽  
Cell Degeneration ◽  
Age Related

Abstract Background Amyloid-β (Aβ), a component of age-related macular degeneration (AMD) hallmark drusen, induces retinal pigment epithelium (RPE) cell degeneration and promotes the progress of AMD. Evidence shows that epigenetics mechanism is involved in the regulation of AMD. In this study, we aimed to investigate the roles of N6-methyladenosine (m6A) and its demethylase the fat mass and obesity-associated gene (FTO) in Aβ-mediated degeneration. Methods The molecular characteristics and morphology of FTO were examined by quantitative Real-Time PCR (qRT-PCR), Western blot and immunofluorescence. Inhibition of FTO was conducted to analyze its function on cell survival. Ocular Coherence Tomography and Fundus Photography was performed to evaluate the fundus of animal models. m6A-mRNA Epi-transcriptomic microarray, bioinformatics analysis and experimental verification were used to explore the potential molecular mechanism and signaling pathway. Results We found overexpression of FTO in Aβ model and demonstrated that inhibition of FTO by the sodium form of Meclofenamic acid (MA1) aggravated RPE impairment. Mechanistically, we identified protein kinase A (PKA) as FTO’s mediating target and found that FTO epigenetically demethylated PKA mRNA and decreased PKA expression, leading to suppressed PKA/ cyclin AMP-responsive element binding (CREB) signaling pathway. Moreover, inhibition of FTO promoted PKA/CREB signaling pathway inducing greater RPE degeneration and death. Conclusions These data demonstrated the functional significance of FTO in Aβ-induced RPE degeneration and the regulatory mechanism of PKA/CREB signaling pathway, implying FTO as a potentially therapeutic target for AMD.

scholarly journals Ocular disease mechanisms elucidated by genetics of human fetal retinal pigment epithelium gene expression

2018 ◽  
Author(s):  
Boxiang Liu ◽  
Melissa A. Calton ◽  
Nathan S. Abell ◽  
Gillie Benchorin ◽  
Michael J. Gloudemans ◽  
...  
Keyword(s):  
Gene Expression ◽  
Retinal Pigment Epithelium ◽  
Large Scale ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Lipid Synthesis ◽  
Age Related Macular Degeneration ◽  
Age Related ◽  
Metabolic Conditions ◽  
Association Data

AbstractThe eye is an intricate organ with limited representation in large-scale functional genomics datasets. The retinal pigment epithelium (RPE) serves vital roles in ocular development and retinal homeostasis. We interrogated the genetics of gene expression of cultured human fetal RPE (fRPE) cells under two metabolic conditions. Genes with disproportionately high fRPE expression are enriched for genes related to inherited ocular diseases. Variants near these fRPE-selective genes explain a larger fraction of risk for both age-related macular degeneration (AMD) and myopia than variants near genes enriched in 53 other human tissues. Increased mitochondrial oxidation of glutamine by fRPE promoted expression of lipid synthesis genes implicated in AMD. Expression and splice quantitative trait loci (e/sQTL) analysis revealed shared and metabolic condition-specific loci of each type and several eQTL not previously described in any tissue. Fine mapping of fRPE e/sQTL across AMD and myopia genome-wide association data suggests new candidate genes, and mechanisms by which the same common variant of RDH5 contributes to both increased AMD risk and decreased myopia risk. Our study highlights the unique transcriptomic characteristics of fRPE and provides a resource to connect e/sQTL in a critical ocular cell type to monogenic and complex eye disorders.

scholarly journals 4-(Phenylsulfanyl) Butan-2-One Attenuates the Inflammatory Response Induced by Amyloid-β Oligomers in Retinal Pigment Epithelium Cells

Marine Drugs ◽  
2020 ◽  
Vol 19 (1) ◽  
pp. 1
Author(s):  
Peeraporn Varinthra ◽  
Shun-Ping Huang ◽  
Supin Chompoopong ◽  
Zhi-Hong Wen ◽  
Ingrid Y. Liu
Keyword(s):  
Retinal Pigment Epithelium ◽  
Inflammatory Response ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Amyloid Β ◽  
Age Related Macular Degeneration ◽  
Epithelial Cell Line ◽  
Age Related ◽  
Tnf Α ◽  
Cox 2

Age-related macular degeneration (AMD) is a progressive eye disease that causes irreversible impairment of central vision, and effective treatment is not yet available. Extracellular accumulation of amyloid-beta (Aβ) in drusen that lie under the retinal pigment epithelium (RPE) has been reported as one of the early signs of AMD and was found in more than 60% of Alzheimer’s disease (AD) patients. Extracellular deposition of Aβ can induce the expression of inflammatory cytokines such as IL-1β, TNF-α, COX-2, and iNOS in RPE cells. Thus, finding a compound that can effectively reduce the inflammatory response may help the treatment of AMD. In this research, we investigated the anti-inflammatory effect of the coral-derived compound 4-(phenylsulfanyl) butan-2-one (4-PSB-2) on Aβ1-42 oligomer (oAβ1-42) added to the human adult retinal pigment epithelial cell line (ARPE-19). Our results demonstrated that 4-PSB-2 can decrease the elevated expressions of TNF-α, COX-2, and iNOS via NF-κB signaling in ARPE-19 cells treated with oAβ1-42 without causing any cytotoxicity or notable side effects. This study suggests that 4-PSB-2 is a promising drug candidate for attenuation of AMD.

scholarly journals Retinal Pigment Epithelium Expressed Toll-like Receptors and Their Potential Role in Age-Related Macular Degeneration

2021 ◽  
Vol 22 (16) ◽  
pp. 8387
Author(s):  
Alexa Klettner ◽  
Johann Roider
Keyword(s):  
Retinal Pigment Epithelium ◽  
Inflammatory Response ◽  
Macular Degeneration ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Age Related Macular Degeneration ◽  
Current Status ◽  
Toll Like Receptors ◽  
Cell Degeneration ◽  
Age Related

(1) Background: Inflammation is a major pathomechanism in the development and progression of age-related macular degeneration (AMD). The retinal pigment epithelium (RPE) may contribute to retinal inflammation via activation of its Toll-like receptors (TLR). TLR are pattern recognition receptors that detect the pathogen- or danger-associated molecular pattern. The involvement of TLR activation in AMD is so far not understood. (2) Methods: We performed a systematic literature research, consulting the National Library of Medicine (PubMed). (3) Results: We identified 106 studies, of which 54 were included in this review. Based on these studies, the current status of TLR in AMD, the effects of TLR in RPE activation and of the interaction of TLR activated RPE with monocytic cells are given, and the potential of TLR activation in RPE as part of the AMD development is discussed. (4) Conclusion: The activation of TLR2, -3, and -4 induces a profound pro-inflammatory response in the RPE that may contribute to (long-term) inflammation by induction of pro-inflammatory cytokines, reducing RPE function and causing RPE cell degeneration, thereby potentially constantly providing new TLR ligands, which could perpetuate and, in the long run, exacerbate the inflammatory response, which may contribute to AMD development. Furthermore, the combined activation of RPE and microglia may exacerbate neurotoxic effects.

Sign in / Sign up

Export Citation Format

Share Document