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

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.

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

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.

JAM-C maintains VEGR2 expression to promote retinal pigment epithelium cell survival under oxidative stress

2017 ◽  
Vol 117 (04) ◽  
pp. 750-757
Author(s):  
Xin Jia ◽  
Chen Zhao ◽  
Qishan Chen ◽  
Yuxiang Du ◽  
Lijuan Huang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Retinal Pigment Epithelium ◽  
Cell Survival ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Retinal Pigment Epithelium Cell ◽  
Photoreceptor Cells ◽  
Rpe Cells

SummaryJunctional adhesion molecule-C (JAM-C) has been shown to play critical roles during development and in immune responses. However, its role in adult eyes under oxidative stress remains poorly understood. Here, we report that JAM-C is abundantly expressed in adult mouse retinae and choroids in vivo and in cultured retinal pigment epithelium (RPE) and photoreceptor cells in vitro. Importantly, both JAM-C expression and its membrane localisation are downregulated by H2O2-induced oxidative stress. Under H2O2-induced oxidative stress, JAM-C is critically required for the survival of human RPE cells. Indeed, loss of JAM-C by siRNA knockdown decreased RPE cell survival. Mechanistically, we show that JAM-C is required to maintain VEGFR2 expression in RPE cells, and VEGFR2 plays an important role in keeping the RPE cells viable since overexpression of VEGFR2 partially restored impaired RPE survival caused by JAM-C knockdown and increased RPE survival. We further show that JAM-C regulates VEGFR2 expression and, in turn, modulates p38 phosphorylation. Together, our data demonstrate that JAM-C plays an important role in maintaining VEGR2 expression to promote RPE cell survival under oxidative stress. Given the vital importance of RPE in the eye, approaches that can modulate JAM-C expression may have therapeutic values in treating diseases with impaired RPE survival.

scholarly journals A ROCK Inhibitor Promotes Graft Survival during Transplantation of iPS-Cell-Derived Retinal Cells

2021 ◽  
Vol 22 (6) ◽  
pp. 3237
Author(s):  
Masaaki Ishida ◽  
Sunao Sugita ◽  
Kenichi Makabe ◽  
Shota Fujii ◽  
Yoko Futatsugi ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Single Cell ◽  
Cell Transplantation ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Cell Suspensions ◽  
Rpe Cells ◽  
Rpe Transplantation

Currently, retinal pigment epithelium (RPE) transplantation includes sheet and single-cell transplantation, the latter of which includes cell death and may be highly immunogenic, and there are some issues to be improved in single-cell transplantation. Y-27632 is an inhibitor of Rho-associated protein kinase (ROCK), the downstream kinase of Rho. We herein investigated the effect of Y-27632 in vitro on retinal pigment epithelium derived from induced pluripotent stem cells (iPS-RPE cells), and also its effects in vivo on the transplantation of iPS-RPE cell suspensions. As a result, the addition of Y-27632 in vitro showed suppression of apoptosis, promotion of cell adhesion, and higher proliferation and pigmentation of iPS-RPE cells. Y-27632 also increased the viability of the transplant without showing obvious retinal toxicity in human iPS-RPE transplantation into monkey subretinal space in vivo. Therefore, it is possible that ROCK inhibitors can improve the engraftment of iPS-RPE cell suspensions after transplantation.

scholarly journals Pathogenic Effects of Mineralocorticoid Pathway Activation in Retinal Pigment Epithelium

2021 ◽  
Vol 22 (17) ◽  
pp. 9618
Author(s):  
Jérémie Canonica ◽  
Min Zhao ◽  
Tatiana Favez ◽  
Emmanuelle Gelizé ◽  
Laurent Jonet ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Retinal Pigment Epithelium ◽  
Barrier Function ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Retinal Diseases ◽  
Mesenchymal Transition ◽  
Rpe Cells ◽  
Pathway Activation ◽  
And Migration

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.

scholarly journals Clinical-grade stem cell–derived retinal pigment epithelium patch rescues retinal degeneration in rodents and pigs

2019 ◽  
Vol 11 (475) ◽  
pp. eaat5580 ◽  
Author(s):  
Ruchi Sharma ◽  
Vladimir Khristov ◽  
Aaron Rising ◽  
Balendu Shekhar Jha ◽  
Roba Dejene ◽  
...  
Keyword(s):  
Stem Cell ◽  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Age Related Macular Degeneration ◽  
Clinical Grade ◽  
Functional Validation ◽  
Age Related

Considerable progress has been made in testing stem cell–derived retinal pigment epithelium (RPE) as a potential therapy for age-related macular degeneration (AMD). However, the recent reports of oncogenic mutations in induced pluripotent stem cells (iPSCs) underlie the need for robust manufacturing and functional validation of clinical-grade iPSC-derived RPE before transplantation. Here, we developed oncogenic mutation-free clinical-grade iPSCs from three AMD patients and differentiated them into clinical-grade iPSC-RPE patches on biodegradable scaffolds. Functional validation of clinical-grade iPSC-RPE patches revealed specific features that distinguished transplantable from nontransplantable patches. Compared to RPE cells in suspension, our biodegradable scaffold approach improved integration and functionality of RPE patches in rats and in a porcine laser-induced RPE injury model that mimics AMD-like eye conditions. Our results suggest that the in vitro and in vivo preclinical functional validation of iPSC-RPE patches developed here might ultimately be useful for evaluation and optimization of autologous iPSC-based therapies.

scholarly journals Avoiding the Pitfalls of siRNA Delivery to the Retinal Pigment Epithelium with Physiologically Relevant Cell Models

Pharmaceutics ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 667
Author(s):  
Eva Ramsay ◽  
Manuela Raviña ◽  
Sanjay Sarkhel ◽  
Sarah Hehir ◽  
Neil R. Cameron ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Cell Model ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Sirna Delivery ◽  
Target Cells ◽  
Cell Models ◽  
Rpe Cells ◽  
Age Related

Inflammation is involved in the pathogenesis of several age-related ocular diseases, such as macular degeneration (AMD), diabetic retinopathy, and glaucoma. The delivery of anti-inflammatory siRNA to the retinal pigment epithelium (RPE) may become a promising therapeutic option for the treatment of inflammation, if the efficient delivery of siRNA to target cells is accomplished. Unfortunately, so far, the siRNA delivery system selection performed in dividing RPE cells in vitro has been a poor predictor of the in vivo efficacy. Our study evaluates the silencing efficiency of polyplexes, lipoplexes, and lipidoid-siRNA complexes in dividing RPE cells as well as in physiologically relevant RPE cell models. We find that RPE cell differentiation alters their endocytic activity and causes a decrease in the uptake of siRNA complexes. In addition, we determine that melanosomal sequestration is another significant and previously unexplored barrier to gene silencing in pigmented cells. In summary, this study highlights the importance of choosing a physiologically relevant RPE cell model for the selection of siRNA delivery systems. Such cell models are expected to enable the identification of carriers with a high probability of success in vivo, and thus propel the development of siRNA therapeutics for ocular disease.

In-vivo and in-vitro selective targeting of the retinal pigment epithelium using a laser-scanning device

2002 ◽  
Author(s):  
Clemens Alt ◽  
Carsten Framme ◽  
Susanne Schnell ◽  
Georg Schuele ◽  
Ralf Brinkmann ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Laser Scanning ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Scanning Device ◽  
Selective Targeting

scholarly journals Effects of Lycium barbarum polysaccharide on the photoinduced autophagy of retinal pigment epithelium cells

2022 ◽  
Vol 15 (1) ◽  
pp. 23-30
Author(s):  
Yuan-Yuan Gao ◽  
◽  
Jie Huang ◽  
Wu-Jun Li ◽  
Yang Yu ◽  
...  
Keyword(s):  
Retinal Pigment Epithelium ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Cell Counting ◽  
High Dose ◽  
Lycium Barbarum ◽  
Rpe Cells ◽  
Expression Levels ◽  
Lycium Barbarum Polysaccharide

AIM: To investigate the relationship between autophagy and apoptosis in photoinduced injuries in retinal pigment epithelium (RPE) cells and how Lycium barbarum polysaccharide (LBP) contributes to the increased of RPE cells to photoinduced autophagy. METHODS: In vitro cultures of human RPE strains (ARPE-19) were prepared and randomly divided into the blank control, model, low-dose LBP, middle-dose LBP, high-dose LBP, and 3-methyladenine (3MA) groups. The viability of the RPE cells and apoptosis levels in each group were tested through cell counting kit-8 (CCK8) method with a flow cytometer (Annexin V/PI double staining technique). The expression levels of LC3II, LC3I, and P62 proteins were detected with the immunofluorescence method. The expression levels of beclin1, LC3, P62, PI3K, P-mTOR, mTOR, P-Akt, and Akt proteins were tested through Western blot. RESULTS: LBP considerably strengthens cell viability and inhibits the apoptosis of RPE cells after photoinduction. The PI3K/Akt/mTOR signal pathway is activated because of the upregulation of the phosphorylation levels of Akt and mTOR proteins, and thus autophagy is inhibited. CONCLUSION: LBP can inhibit the excessive autophagy in RPE cells by activating the PI3K/Akt/mTOR signaling pathways and thereby protect RPE cells from photoinduced injuries.

Sign in / Sign up

Export Citation Format

Share Document