scholarly journals Ginsenoside-Rb1 Induces ARPE-19 Proliferation and Reduces VEGF Release

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Brandi S. Betts ◽  
Kalpana Parvathaneni ◽  
Bharat B. Yendluri ◽  
Jeffery Grigsby ◽  
Andrew T. C. Tsin
Keyword(s):  
Cell Proliferation ◽  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Ginseng Root ◽  
Root Extract ◽  
Ginsenoside Rb1 ◽  
Rpe Cells ◽  
Viable Cells ◽  
Age Related ◽  
Vegf Release

Rb1, a ginsenoside from ginseng root extract, possesses antiangiogenic effects, but its role on ocular cells has not been studied. We hypothesize that Rb1 inhibits the production of the angiogenic cytokine VEGF from ARPE-19 cells, leading to a significant reduction in the proliferation of ocular vasculatures. Data from our experiments show that Rb1 induced an increase in the number of ARPE cells in culture, while VEGF release (pg/10,000 viable cells) was significantly reduced. Treatment with VEGF and cotreatment with Rb1 and VEGF showed that this Rb1-induced cell proliferation was mediated by VEGF. Because VEGF from RPE plays a major role in promoting angiogenesis in ocular vasculatures. Our finding that Rb1 inhibits the release of VEGF from RPE cells suggests that Rb1 has a significant role in the eye to protect against angiogenic diseases such as age-related macular degeneration.

scholarly journals Dietary Polyphenols in Age-Related Macular Degeneration: Protection against Oxidative Stress and Beyond

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Elzbieta Pawlowska ◽  
Joanna Szczepanska ◽  
Ali Koskela ◽  
Kai Kaarniranta ◽  
Janusz Blasiak
Keyword(s):  
Oxidative Stress ◽  
Macular Degeneration ◽  
Retinal Pigment ◽  
Janus Kinase ◽  
Age Related Macular Degeneration ◽  
Hydroxyl Groups ◽  
Ros Scavenging ◽  
Rpe Cells ◽  
Dietary Polyphenols ◽  
Age Related

Age-related macular degeneration (AMD) is a multifactorial disease of the retina featured by degeneration and loss of photoreceptors and retinal pigment epithelium (RPE) cells with oxidative stress playing a role in its pathology. Although systematic reviews do not support the protective role of diet rich in antioxidants against AMD, dietary polyphenols (DPs) have been reported to have beneficial effects on vision. Some of them, such as quercetin and cyanidin-3-glucoside, can directly scavenge reactive oxygen species (ROS) due to the presence of two hydroxyl groups in their B ring structure. Apart from direct ROS scavenging, DPs can lower oxidative stress in several other pathways. Many DPs induce NRF2 (nuclear factor, erythroid 2-like 2) activation and expression of phase II enzymes that are under transcriptional control of this factor. DPs can inhibit A2E photooxidation in RPE cells, which is a source of oxidative stress. Anti-inflammatory action of DPs in RPE cells is associated with regulation of various interleukins and signaling pathways, including IL-6/JAK2 (Janus kinase 2)/STAT3. Some DPs can improve impaired cellular waste clearance, including AMD-specific deficient phagocytosis of the Aβ42 peptide and autophagy.

scholarly journals Protective Effects of Curcumin Ester Prodrug, Curcumin Diethyl Disuccinate against H2O2-Induced Oxidative Stress in Human Retinal Pigment Epithelial Cells: Potential Therapeutic Avenues for Age-Related Macular Degeneration

2019 ◽  
Vol 20 (13) ◽  
pp. 3367 ◽  
Author(s):  
Chawanphat Muangnoi ◽  
Umar Sharif ◽  
Pahweenvaj Ratnatilaka Na Bhuket ◽  
Pornchai Rojsitthisak ◽  
Luminita Paraoan
Keyword(s):  
Oxidative Stress ◽  
Macular Degeneration ◽  
Retinal Pigment ◽  
Parent Drug ◽  
Retinal Pigment Epithelial Cells ◽  
Age Related Macular Degeneration ◽  
Protective Effects ◽  
Rpe Cells ◽  
Age Related ◽  
Potent Drug

Oxidative stress-induced damage to the retinal pigmented epithelium (RPE), a specialised post-mitotic monolayer that maintains retinal homeostasis, contributes to the development of age-related macular degeneration (AMD). Curcumin (Cur), a naturally occurring antioxidant, was previously shown to have the ability to protect RPE cells from oxidative stress. However, poor solubility and bioavailability makes Cur a poor therapeutic agent. As prodrug approaches can mitigate these limitations, we compared the protective properties of the Cur prodrug curcumin diethyl disuccinate (CurDD) against Cur in relation to oxidative stress induced in human ARPE-19 cells. Both CurDD and Cur significantly decreased H2O2-induced reactive oxygen species (ROS) production and protected RPE cells from oxidative stress-induced death. Both drugs exerted their protective effects through the modulation of p44/42 (ERK) and the involvement of downstream molecules Bax and Bcl-2. Additionally, the expression of antioxidant enzymes HO-1 and NQO1 was also enhanced in cells treated with CurDD and Cur. In all cases, CurDD was more effective than its parent drug against oxidative stress-induced damage to ARPE-19 cells. These findings highlight CurDD as a more potent drug compared to Cur against oxidative stress and indicate that its protective effects are exerted through modulation of key apoptotic and antioxidant molecular pathways.

Engineered safe and immune-tolerant ‘designer’ rpe cells towards the treatment of age-related macular degeneration

Cytotherapy ◽  
2021 ◽  
Vol 23 (5) ◽  
pp. S19
Author(s):  
S. Hacibekiroglu ◽  
E. Jong ◽  
J. Tang ◽  
T. Oussenko ◽  
M. Ho ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Rpe Cells ◽  
Age Related ◽  
Immune Tolerant

scholarly journals Detrimental Effects of UVB on Retinal Pigment Epithelial Cells and Its Role in Age-Related Macular Degeneration

2020 ◽  
Vol 2020 ◽  
pp. 1-29 ◽  
Author(s):  
Camille Keisha Mahendra ◽  
Loh Teng Hern Tan ◽  
Priyia Pusparajah ◽  
Thet Thet Htar ◽  
Lay-Hong Chuah ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Bioactive Compounds ◽  
Retinal Pigment Epithelial ◽  
Retinal Pigment ◽  
Age Related Macular Degeneration ◽  
Cumulative Exposure ◽  
Rpe Cells ◽  
Pigment Epithelial ◽  
Age Related

Retinal pigment epithelial (RPE) cells are an essential part of the human eye because they not only mediate and control the transfer of fluids and solutes but also protect the retina against photooxidative damage and renew photoreceptor cells through phagocytosis. However, their function necessitates cumulative exposure to the sun resulting in UV damage, which may lead to the development of age-related macular degeneration (AMD). Several studies have shown that UVB induces direct DNA damage and oxidative stress in RPE cells by increasing ROS and dysregulating endogenous antioxidants. Activation of different signaling pathways connected to inflammation, cell cycle arrest, and intrinsic apoptosis was reported as well. Besides that, essential functions like phagocytosis, osmoregulation, and water permeability of RPE cells were also affected. Although the melanin within RPE cells can act as a photoprotectant, this photoprotection decreases with age. Nevertheless, the changes in lens epithelium-derived growth factor (LEDGF) and autophagic activity or application of bioactive compounds from natural products can reverse the detrimental effect of UVB. Additionally, in vivo studies on the whole retina demonstrated that UVB irradiation induces gene and protein level dysregulation, indicating cellular stress and aberrations in the chromosome level. Morphological changes like retinal depigmentation and drusen formation were noted as well which is similar to the etiology of AMD, suggesting the connection of UVB damage with AMD. Therefore, future studies, which include mechanism studies via in vitro or in vivo and other potential bioactive compounds, should be pursued for a better understanding of the involvement of UVB in AMD.

scholarly journals Control of Complement Activation by the Long Pentraxin PTX3: Implications in Age-Related Macular Degeneration

2020 ◽  
Vol 11 ◽  
Author(s):  
Matteo Stravalaci ◽  
Francesca Davi ◽  
Raffaella Parente ◽  
Marco Gobbi ◽  
Barbara Bottazzi ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Complement Activation ◽  
Hot Spot ◽  
Alternative Pathway ◽  
Retinal Pigment ◽  
Factor H ◽  
Age Related Macular Degeneration ◽  
Complement Factor ◽  
Rpe Cells ◽  
Age Related

Dysregulation of the complement system is central to age-related macular degeneration (AMD), the leading cause of blindness in the developed world. Most of the genetic variation associated with AMD resides in complement genes, with the greatest risk associated with polymorphisms in the complement factor H (CFH) gene; factor H (FH) is the major inhibitor of the alternative pathway (AP) of complement that specifically targets C3b and the AP C3 convertase. Long pentraxin 3 (PTX3) is a soluble pattern recognition molecule that has been proposed to inhibit AP activation via recruitment of FH. Although present in the human retina, if and how PTX3 plays a role in AMD is still unclear. In this work we demonstrated the presence of PTX3 in the human vitreous and studied the PTX3-FH-C3b crosstalk and its effects on complement activation in a model of retinal pigment epithelium (RPE). RPE cells cultured in inflammatory AMD-like conditions overexpressed the PTX3 protein, and up-regulated AP activating genes. PTX3 bound RPE cells in a physiological setting, however this interaction was reduced in inflammatory conditions, whereby PTX3 had no complement-inhibiting activity on inflamed RPE. However, on non-cellular surfaces, PTX3 formed a stable ternary complex with FH and C3b that acted as a “hot spot” for complement inhibition. Our findings suggest a protective role for PTX3 in response to complement dysregulation in AMD and point to a novel mechanism of complement regulation by this pentraxin with potential implications in pathology and pharmacology of AMD.

scholarly journals Cellular Senescence in Age-Related Macular Degeneration: Can Autophagy and DNA Damage Response Play a Role?

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Janusz Blasiak ◽  
Malgorzata Piechota ◽  
Elzbieta Pawlowska ◽  
Magdalena Szatkowska ◽  
Ewa Sikora ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Dna Damage ◽  
Macular Degeneration ◽  
Dna Damage Response ◽  
Cellular Senescence ◽  
Cell Senescence ◽  
Age Related Macular Degeneration ◽  
Rpe Cells ◽  
Age Related ◽  
Damage Response

Age-related macular degeneration (AMD) is the main reason of blindness in developed countries. Aging is the main AMD risk factor. Oxidative stress, inflammation and some genetic factors play a role in AMD pathogenesis. AMD is associated with the degradation of retinal pigment epithelium (RPE) cells, photoreceptors, and choriocapillaris. Lost RPE cells in the central retina can be replaced by their peripheral counterparts. However, if they are senescent, degenerated regions in the macula cannot be regenerated. Oxidative stress, a main factor of AMD pathogenesis, can induce DNA damage response (DDR), autophagy, and cell senescence. Moreover, cell senescence is involved in the pathogenesis of many age-related diseases. Cell senescence is the state of permanent cellular division arrest and concerns only mitotic cells. RPE cells, although quiescent in the retina, can proliferate in vitro. They can also undergo oxidative stress-induced senescence. Therefore, cellular senescence can be considered as an important molecular pathway of AMD pathology, resulting in an inability of the macula to regenerate after degeneration of RPE cells caused by a factor inducing DDR and autophagy. It is too early to speculate about the role of the mutual interplay between cell senescence, autophagy, and DDR, but this subject is worth further studies.

scholarly journals NLRP3 Inflammasome: Activation and Regulation in Age-Related Macular Degeneration

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Jiangyuan Gao ◽  
Ruozhou Tom Liu ◽  
Sijia Cao ◽  
Jing Z. Cui ◽  
Aikun Wang ◽  
...  
Keyword(s):  
Macular Degeneration ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
The Elderly ◽  
Geographic Atrophy ◽  
Age Related Macular Degeneration ◽  
Inflammasome Activation ◽  
Related Factors ◽  
Rpe Cells ◽  
Age Related

Age-related macular degeneration (AMD) is the leading cause of legal blindness in the elderly in industrialized countries. AMD is a multifactorial disease influenced by both genetic and environmental risk factors. Progression of AMD is characterized by an increase in the number and size of drusen, extracellular deposits, which accumulate between the retinal pigment epithelium (RPE) and Bruch’s membrane (BM) in outer retina. The major pathways associated with its pathogenesis include oxidative stress and inflammation in the early stages of AMD. Little is known about the interactions among these mechanisms that drive the transition from early to late stages of AMD, such as geographic atrophy (GA) or choroidal neovascularization (CNV). As part of the innate immune system, inflammasome activation has been identified in RPE cells and proposed to be a causal factor for RPE dysfunction and degeneration. Here, we will first review the classic model of inflammasome activation, then discuss the potentials of AMD-related factors to activate the inflammasome in both nonocular immune cells and RPE cells, and finally introduce several novel mechanisms for regulating the inflammasome activity.

scholarly journals Efficacy of Ethanol Extract ofFructus lyciiand Its Constituents Lutein/Zeaxanthin in Protecting Retinal Pigment Epithelium Cells against Oxidative Stress:In VivoandIn VitroModels of Age-Related Macular Degeneration

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Xinrong Xu ◽  
Li Hang ◽  
Binglin Huang ◽  
Yuanhua Wei ◽  
Shizhong Zheng ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Retinal Pigment Epithelium ◽  
Macular Degeneration ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Ethanol Extract ◽  
Age Related Macular Degeneration ◽  
Age Related ◽  
Fructus Lycii

Age-related macular degeneration (AMD) is a major cause of blindness worldwide. Oxidative stress plays a large role in the pathogenesis of AMD. The present study was to evaluate the effects ofFructus lyciiethanol extract on AMD in mice and to investigate whether combination of lutein and zeaxanthin, two carotenoid pigments inFructus lycii, could protect human retinal pigment epithelial ARPE-19 cells treated with hydrogen peroxide (H2O2)in vitro. We found that severe sediment beneath retinal pigment epithelium and thickened Bruch membrane occurred in AMD mice. However,Fructus lyciiethanol extract improved the histopathologic changes and decreased the thickness of Bruch membrane. Furthermore, the gene and protein expression of cathepsin B and cystatin C was upregulated in AMD mice but was eliminated byFructus lyciiethanol extract. Investigationsin vitroshowed that ARPE-19 cell proliferation was suppressed by H2O2. However, lutein/zeaxanthin not only stimulated cell proliferation but also abrogated the enhanced expression of MMP-2 and TIMP-1 in H2O2-treated ARPE-19 cells. These data collectively suggested thatFructus lyciiethanol extract and its active components lutein/zeaxanthin had protective effects on AMDin vivoandin vitro, providing novel insights into the beneficial role ofFructus lyciifor AMD therapy.

Sign in / Sign up

Export Citation Format

Share Document