Pathogenic Effects of Mineralocorticoid Pathway Activation in Retinal Pigment Epithelium

Glucocorticoids are amongst the most used drugs to treat retinal diseases of various origins. Yet, the transcriptional regulations induced by glucocorticoid receptor (GR) and mineralocorticoid receptor (MR) activation in retinal pigment epithelium cells (RPE) that form the outer blood–retina barrier are unknown. Levels of endogenous corticoids, ligands for MR and GR, were measured in human ocular media. Human RPE cells derived from induced pluripotent stem cells (iRPE) were used to analyze the pan-transcriptional regulations induced by aldosterone—an MR-specific agonist, or cortisol or cortisol + RU486—a GR antagonist. The retinal phenotype of transgenic mice that overexpress the human MR (P1.hMR) was analyzed. In the human eye, the main ligand for GR and MR is cortisol. The iRPE cells express functional GR and MR. The subset of genes regulated by aldosterone and by cortisol + RU-486, and not by cortisol alone, mimics an imbalance toward MR activation. They are involved in extracellular matrix remodeling (CNN1, MGP, AMTN), epithelial–mesenchymal transition, RPE cell proliferation and migration (ITGB3, PLAUR and FOSL1) and immune balance (TNFSF18 and PTX3). The P1.hMR mice showed choroidal vasodilation, focal alteration of the RPE/choroid interface and migration of RPE cells together with RPE barrier function alteration, similar to human retinal diseases within the pachychoroid spectrum. RPE is a corticosteroid-sensitive epithelium. MR pathway activation in the RPE regulates genes involved in barrier function, extracellular matrix, neural regulation and epithelial differentiation, which could contribute to retinal pathology.

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Glucosamine inhibits epithelial-to-mesenchymal transition and migration of retinal pigment epithelium cells in culture and morphologic changes in a mouse model of proliferative vitreoretinopathy

Acta Ophthalmologica ◽

10.1111/j.1755-3768.2011.02147.x ◽

2011 ◽

Vol 89 (6) ◽

pp. e505-e514 ◽

Cited By ~ 19

Author(s):

Chang-Min Liang ◽

Ming-Cheng Tai ◽

Yun-Hsiang Chang ◽

Yi-Hao Chen ◽

Ching-Long Chen ◽

...

Keyword(s):

Retinal Pigment Epithelium ◽

Mouse Model ◽

Epithelial To Mesenchymal Transition ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Mesenchymal Transition ◽

Retinal Pigment Epithelium Cells ◽

And Migration ◽

Epithelium Cells ◽

Morphologic Changes

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Transcriptomic Profiling of Human Pluripotent Stem Cell-Derived Retinal Pigment Epithelium Over Time

10.1101/842328 ◽

2019 ◽

Author(s):

Grace E. Lidgerwood ◽

Anne Senabouth ◽

Casey J.A. Smith-Anttila ◽

Vikkitharan Gnanasambandapillai ◽

Dominik C. Kaczorowski ◽

...

Keyword(s):

Stem Cell ◽

Retinal Pigment Epithelium ◽

Pluripotent Stem Cell ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Embryonic Stem Cell Line ◽

Embryonic Stem ◽

Human Pluripotent Stem Cell ◽

Mesenchymal Transition ◽

Rpe Cells

AbstractHuman pluripotent stem cell (hPSC)-derived progenies are immature versions of cells, presenting a potential limitation to the accurate modelling of disease associated with maturity or age. Hence, it is important to characterise how closely cells used in culture resemble their native counterparts. In order to select appropriate points in time for RPE cultures to reflect native counterparts, we characterised the transcriptomic profiles of hPSC-derived retinal pigment epithelium (RPE) cells from 1- and 12-month cultures. We differentiated the human embryonic stem cell line H9 into RPE cells, performed single cell RNA-sequencing of a total of 16,576 cells, and analysed the resulting data to assess the molecular changes of RPE cells across these two culture time points. Our results indicate the stability of the RPE transcriptomic signature, with no evidence of an epithelial – mesenchymal transition, and with maturing populations of RPE observed with time in culture. Assessment of gene ontology pathways revealed that as cultures age, RPE cells upregulate expression of genes involved in metal binding and antioxidant functions. This might reflect an increased ability to handle oxidative stress as cells mature. Comparison with native human RPE data confirmed a maturing transcriptional profile of RPE cells in culture. These results suggest that in vitro long-term culture of RPE cells allow the modelling of specific phenotypes observed in native mature tissue. Our work highlights the transcriptional landscape of hPSC-derived RPE as they age in culture, which provides a reference for native and patient-samples to be benchmarked against.

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Nanoceria Particles Are an Eligible Candidate to Prevent Age-Related Macular Degeneration by Inhibiting Retinal Pigment Epithelium Cell Death and Autophagy Alterations

Cells ◽

10.3390/cells9071617 ◽

2020 ◽

Vol 9 (7) ◽

pp. 1617 ◽

Cited By ~ 4

Author(s):

Annamaria Tisi ◽

Vincenzo Flati ◽

Simona Delle Monache ◽

Luca Lozzi ◽

Maurizio Passacantando ◽

...

Keyword(s):

Cell Death ◽

Retinal Pigment Epithelium ◽

Macular Degeneration ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Age Related Macular Degeneration ◽

Cellular Damage ◽

Mesenchymal Transition ◽

Rpe Cells ◽

Age Related

Retinal pigment epithelium (RPE) dysfunction and degeneration underlie the development of age-related macular degeneration (AMD), which is the leading cause of blindness worldwide. In this study, we investigated whether cerium oxide nanoparticles (CeO2-NPs or nanoceria), which are anti-oxidant agents with auto-regenerative properties, are able to preserve the RPE. On ARPE-19 cells, we found that CeO2-NPs promoted cell viability against H2O2–induced cellular damage. For the in vivo studies, we used a rat model of acute light damage (LD), which mimics many features of AMD. CeO2-NPs intravitreally injected three days before LD prevented RPE cell death and degeneration and nanoceria labelled with fluorescein were found localized in the cytoplasm of RPE cells. CeO2-NPs inhibited epithelial-mesenchymal transition of RPE cells and modulated autophagy by the down-regulation of LC3B-II and p62. Moreover, the treatment inhibited nuclear localization of LC3B. Taken together, our study demonstrates that CeO2-NPs represent an eligible candidate to counteract RPE degeneration and, therefore, a powerful therapy for AMD.

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LRG1 promotes epithelial-mesenchymal transition of retinal pigment epithelium cells by activating NOX4

International Journal of Ophthalmology ◽

10.18240/ijo.2021.03.03 ◽

2021 ◽

Vol 14 (3) ◽

pp. 349-355

Author(s):

Li Zhou ◽

◽

Wen-Juan Chu ◽

Ling-Ling Yang ◽

Hai-Feng Xu ◽

...

Keyword(s):

Retinal Pigment Epithelium ◽

Protein Expression ◽

Epithelial Mesenchymal Transition ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Down Regulation ◽

Mesenchymal Transition ◽

Rpe Cells ◽

Mrna And Protein Expression ◽

Tgf Β1

AIM: To investigate the effect of leucine-rich-alpha-2-glycoprotein 1 (LRG1) on epithelial-mesenchymal transition (EMT) in retinal pigment epithelium (RPE) cells, and to explore the role of NADPH oxidase 4 (NOX4). METHODS: RPE cells (ARPE-19 cell line) were treated with transforming growth factor-β1 (TGF-β1) to induce EMT. Changes of the mRNA and protein expression levels of LRG1 were tested in the TGF-β1 treated cells. The recombinant human LRG1 protein (rLRG1) and siRNA of LRG1 were used to establish accumulation of exogenous LRG1 model and the down-regulation of LRG1 model in ARPE-19 cells respectively, and to detect EMT-related markers including fibronectin, α-smooth muscle actin (α-SMA) and zonula occludens-1 (ZO-1). The mRNA and protein expression level of NOX4 were measured according to the above treatments. VAS2870 was used as a NOX4 inhibitor in rLRG1-treated cells. EMT-related markers were detected to verify the effect of NOX4 in the process of EMT. RESULTS: TGF-β1 promoted the expression of LRG1 at both the mRNA and protein levels during the process of EMT which showed the up-regulation of fibronectin and α-SMA, as well as the down-regulation of ZO-1. Furthermore, the rLRG1 promoted EMT of ARPE-19 cells, which manifested high levels of fibronectin and α-SMA and low level of ZO-1, whereas knockdown of LRG1 prevented EMT by decreasing the expressions of fibronectin and α-SMA and increasing the expression of ZO-1 in ARPE-19 cells. Besides, the rLRG1 activated and LRG1 siRNA suppressed NOX4 expression. EMT was inhibited when VAS2870 was used in the rLRG1-treated cells. CONCLUSION: These results for the first time demonstrate that LRG1 promotes EMT of RPE cells by activating NOX4, which may provide a novel direction to explore the mechanisms of subretinal fibrosis.

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Grape Seed Proanthocyanindin Extract Moderated Retinal Pigment Epithelium Cellular Senescence Through NAMPT/SIRT1/NLRP3 Pathway

10.21203/rs.3.rs-230519/v1 ◽

2021 ◽

Author(s):

Yan Wu ◽

Sanyou Dai ◽

Yang Long ◽

Hongzhuo Liu ◽

Weiwei Wan ◽

...

Keyword(s):

Retinal Pigment Epithelium ◽

Cellular Senescence ◽

Barrier Function ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Grape Seed ◽

Rpe Cells ◽

Mitochondrial Homeostasis

Abstract Background: Cellular senescence of retinal pigment epithelium (RPE) cell was an important cause of degenerative retinal disorders, however, the potential effects of grape seed proanthocyanindin extract (GSPE) through regulating NAMPT/SIRT1/NLRP3 pathway remained unclear.Methods: The effects of GSPE on the cellular senescence biomarkers as well as NAMPT and NAD+ contents were detected in both in-vivo and in-vitro RPE cell models. The protection of GSPE treatment on the mitochondrial homeostasis and barrier function of RPE cells were detected with mtDNA lesions, JC-1 staining, ZO1 expression, trans-epithelial cell resistance (TEER) as well as senescence-associated secretory phenotype (SASP) expressions. The GSPE treatment with NAMPT inhibitor, Fk866, and SIRT1 inhibitor, EX-527, was used in the potential NAMPT/SIRT1/NLRP3 mechanism detection.Results: GSPE significantly improve the NAMPT and NAD+ content in aging mice and thus alleviated the RPE cellular senescence. In advanced in-vitro studies, GSPE could be an activator of NAMPT and thus relieved H2O2 induced NAD+ depression. In advanced analyses, it was reported that GSPE could alleviate mitochondrial homeostasis, barrier function and SASP of aging RPE cells. Thus, detection the SASP in in-vitro aging model provided us knowledge in the understanding of the anti-aging role of GSPE and following detailed pathological mechanism analyses demonstrated that GSPE demonstrated the protective effects in aging RPE cells through NAMPT/SIRT1/NLRP3 pathway.Conclusions: These findings indicate that GSPE alleviated cellular senescence both in-vivo and in-vitro through NAMPT/SIRT1/NLRP3 pathway. This study highlighted the importance both the potential GSPE in degenerative retinopathy as well as the crosstalk of NAD+ metabolism, SIRT1 function and NLRP3 activation.

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Taurine rescues mitochondria-related metabolic impairments in the patient-derived induced pluripotent stem cells and epithelial-mesenchymal transition in the retinal pigment epithelium

Redox Biology ◽

10.1016/j.redox.2021.101921 ◽

2021 ◽

Vol 41 ◽

pp. 101921

Author(s):

Kohei Homma ◽

Eriko Toda ◽

Hideto Osada ◽

Norihiro Nagai ◽

Takumi Era ◽

...

Keyword(s):

Stem Cells ◽

Retinal Pigment Epithelium ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Epithelial Mesenchymal Transition ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Mesenchymal Transition ◽

Induced Pluripotent ◽

Metabolic Impairments

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The cytoskeletal elements of human retinal pigment epithelium: in vitro and in vivo

Journal of Cell Science ◽

10.1242/jcs.91.2.303 ◽

1988 ◽

Vol 91 (2) ◽

pp. 303-312

Author(s):

N.M. McKechnie ◽

M. Boulton ◽

H.L. Robey ◽

F.J. Savage ◽

I. Grierson

Keyword(s):

Retinal Pigment Epithelium ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Cytokeratin 18 ◽

Rpe Cells ◽

Human Retinal Pigment Epithelium ◽

Cytoskeletal Elements

The cytoskeletal elements of normal (in situ) and cultured human retinal pigment epithelium (RPE) were studied by a variety of immunocytochemical techniques. Primary antibodies to vimentin and cytokeratins were used. Positive immunoreactivity for vimentin was obtained with in situ and cultured material. The pattern of reactivity obtained with antisera and monoclonals to cytokeratins was more complex. Cytokeratin immunoreactivity could be demonstrated in situ and in cultured cells. The pattern of cytokeratin expression was similar to that of simple or glandular epithelia. A monoclonal antibody that specifically recognizes cytokeratin 18 identified a population of cultured RPE cells that had particularly well-defined filamentous networks within their cytoplasm. Freshly isolated RPE was cytokeratin 18 negative by immunofluorescence, but upon culture cytokeratin 18 positive cells were identifiable. Cytokeratin 18 positive cells were identified in all RPE cultures (other than early primaries), regardless of passage number, age or sex of the donor. In post-confluent cultures cytokeratin 18 cells were identified growing over cytokeratin 18 negative cells, suggesting an association of cytokeratin 18 immunoreactivity with cell proliferation. Immunofluorescence studies of retinal scar tissue from two individuals revealed the presence of numerous cytokeratin 18 positive cells. These findings indicate that RPE cells can be identified by their cytokeratin immunoreactivity and that the overt expression of cytokeratin 18 may be associated with proliferation of human RPE both in vitro and in vivo.

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