Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascula...Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascular endothelial growth factor therapies against neovascular age-related macular degeneration;however, effective treatment is not yet available for geographical atrophy in dry agerelated macular degeneration or for preventing the progression from early or mid to the late stage of age-related macular degeneration. Both clinical and experimental investigations involving human agerelated macular degeneration retinas and animal models point towards the atrophic alterations in retinal pigment epithelium as a key feature in age-related macular degeneration progression. Retinal pigment epithelium cells are primarily responsible for cellular-structural maintenance and nutrition supply to keep photoreceptors healthy and functional. The retinal pigment epithelium constantly endures a highly oxidative environment that is balanced with a cascade of antioxidant enzyme systems regulated by nuclear factor erythroid-2-related factor 2 as a main redox sensing transcription factor. Aging and accumulated oxidative stress triggers retinal pigment epithelium dysfunction and eventually death. Exposure to both environmental and genetic factors aggravates oxidative stress damage in aging retinal pigment epithelium and accelerates retinal pigment epithelium degeneration in age-related macular degeneration pathophysiology. The present review summarizes the role of oxidative stress in retinal pigment epithelium degeneration, with potential impacts from both genetic and environmental factors in age-related macular degeneration development and progression. Potential strategies to counter retinal pigment epithelium damage and protect the retinal pigment epithelium through enhancing its antioxidant capacity are also discussed, focusing on existing antioxidant nutritional supplementation, and exploring nuclear factor erythroid-2-relat展开更多
The retinal pigment epithelium(RPE)is fundamental to sustaining retinal homeostasis.RPE abnormality leads to visual defects and blindness,including age-related macular degeneration(AMD).Although breakthroughs have bee...The retinal pigment epithelium(RPE)is fundamental to sustaining retinal homeostasis.RPE abnormality leads to visual defects and blindness,including age-related macular degeneration(AMD).Although breakthroughs have been made in the treatment of neovascular AMD,effective intervention for atrophic AMD is largely absent.The adequate knowledge of RPE pathology is hindered by a lack of the patients'RPE datasets,especially at the single-cell resolution.In the current study,we delved into a large-scale single-cell resource of AMD donors,in which RPE cells were occupied in a substantial proportion.Bulk RNA-seq datasets of atrophic AMD were integrated to extract molecular characteristics of RPE in the pathogenesis of atrophic AMD.Both in vivo and in vitro models revealed that carboxypeptidase X,M14 family member 2(CPXM2),was specifically expressed in the RPE cells of atrophic AMD,which might be induced by oxidative stress and involved in the epithelial-mesenchymal transition of RPE cells.Additionally,silencing of CPXM2 inhibited the mesenchymal phenotype of RPE cells in an oxidative stress cell model.Thus,our results demonstrated that CPXM2 played a crucial role in regulating atrophic AMD and might serve as a potential therapeutic target for atrophic AMD.展开更多
Choroidal neovascularization characterizes wet age-related macular degeneration.Choroidal neovascularization formation involves a primarily angiogenic process that is combined with both inflammation and proteolysis.A ...Choroidal neovascularization characterizes wet age-related macular degeneration.Choroidal neovascularization formation involves a primarily angiogenic process that is combined with both inflammation and proteolysis.A primary cause of choroidal neovascularization pathogenesis is alterations in pro-and anti-angiogenic factors derived from the retinal pigment epithelium,with vascular endothelium growth factor being mainly responsible for both clinical and experimental choroidal neovascularization.MicroRNAs(miRNAs)which are short,non-coding,endogenous RNA molecules have a major role in regulating various pathological processes,including inflammation and angiogenesis.A review of recent studies with the mouse laser-induced choroidal neovascularization model has shown alterations in miRNA expression in choroidal neovascularization tissues and could be potential therapeutic targets for wet age-related macular degeneration.Upregulation of miR-505(days 1 and 3 post-laser),miR-155(day 14)occurred in retina;miR-342-5p(days 3 and 7),miR-126-3p(day 14)in choroid;miR-23a,miR-24,miR-27a(day 7)in retina/choroid;miR-505(days 1 and 3)in retinal pigment epithelium/choroid;downregulation of miR-155(days 1 and 3),miR-29a,miR-29b,miR-29c(day 5),miR-93(day 14),miR-126(day 14)occurred in retinal pigment epithelium/choroid.Therapies using miRNA mimics or inhibitors were found to decrease choroidal neovascularization lesions.Choroidal neovascularization development was reduced by overexpression of miR-155,miR-188-5p,miR-(5,B,7),miR-126-3p,miR-342-5p,miR-93,miR-126,miR-195a-3p,miR-24,miR-21,miR-31,miR-150,and miR-184,or suppression of miR-505,miR-126-3p,miR-155,and miR-23/27.Further studies are warranted to determine miRNA expression in mouse laser-induced choroidal neovascularization models in order to validate and extend the reported findings.Important experimental variables need to be standardized;these include the strain and age of animals,gender,number and position of laser burns to the eye,laser parameters to induce choroidal neovascu展开更多
Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for th...Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.展开更多
AIM: To evaluate the long-term anatomical and visual outcomes of drusenoid pigment epithelial detachment(D-PED) in intermediate age-related macular degeneration(AMD) eyes treated with 577 nm yellow subthreshold microp...AIM: To evaluate the long-term anatomical and visual outcomes of drusenoid pigment epithelial detachment(D-PED) in intermediate age-related macular degeneration(AMD) eyes treated with 577 nm yellow subthreshold micropulse laser(SML).METHODS: In this retrospective study, 21 eyes of 16 patients with D-PED in intermediate AMD were consecutively included and assessed.All the eyes were treated with 577 nm SML in several sessions according to D-PED growth status.The logarithm of the minimum angle of resolution(logMAR) best-corrected visual acuity(BCVA) were assessed at the initial visit and after treatment.Spectral-domain optical coherence tomography(SD-OCT) was performed to evaluate the D-PED lifecycle by volumetric calculations.Regression analysis was used to determine the breakpoint, growth, and collapse rate of the D-PED lesions.The progression to advanced AMD was also documented.RESULTS: All the eyes were treated with SML for 2.9±1.0 sessions.The mean follow-up period was 25.3±12.6 mo.The BCVA was stable from the baseline to final visit.All the eyes were categorized into two groups according to the anatomical changes of the D-PED lesion: the collapse group(n=6, 28.6%) and non-collapse group(n=15, 71.4%).The change in logMAR BCVA did not differ significantly between the collapse group 0.00(-0.31, 0.85) and non-collapse group 0.00(0.00, 0.00;P=1).Regression analysis showed that the growth rate was significantly higher in the collapse group(0.090±0.095 mm;/mo) than in the non-collapse group(0.025±0.035 mm;/mo;P<0.001).One eye(4.8%) developed macular neovascularization at 11 mo after SML treatment in the non-collapse group.Three eyes(14.3%) developed geographic atrophy(GA) in the collapse group.CONCLUSION: Compared to the natural course of D-PED reported by previous studies, our results preliminarily show that SML can alleviate visual loss and possibility of progression to advanced AMD in eyes with D-PED in intermediate AMD.A controlled clinical trial needs to further verify the benefit of the intervention.展开更多
Background:Age-related macular degeneration(AMD)is the leading cause of vision loss worldwide.However,the mechanisms involved in the development and progression of AMD are poorly delineated.We aimed to explore the cri...Background:Age-related macular degeneration(AMD)is the leading cause of vision loss worldwide.However,the mechanisms involved in the development and progression of AMD are poorly delineated.We aimed to explore the critical genes involved in the progression of AMD.Methods:The differentially expressed genes(DEGs)in AMD retinal pigment epithelial(RPE)/choroid tissues were identified using the microarray datasets GSE99248 and GSE125564,which were downloaded from the gene expression omnibus database.The overlapping DEGs from the two datasets were screened to identify DEG-related biological pathways using gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses.The hub genes were identified from these DEGs through protein-protein interaction network analyses.The expression levels of hub genes were evaluated by quantitative real-time polymerase chain reaction following the induction of senescence in ARPE-19 with FK866.Following the identification of AMD-related key genes,the potential small molecule compounds targeting the key genes were predicted by PharmacoDB.Finally,a microRNA-gene interaction network was constructed.Results:Microarray analyses identified 174 DEGs in the AMD RPE compared to the healthy RPE samples.These DEGs were primarily enriched in the pathways involved in the regulation of DNA replication,cell cycle,and proteasome-mediated protein polyubiquitination.Among the top ten hub genes,HSP90AA1,CHEK1,PSMA4,PSMD4,and PSMD8 were upregulated in the senescent ARPE-19 cells.Additionally,the drugs targeting HSP90AA1,CHEK1,and PSMA4 were identified.We hypothesize that Hsa-miR-16-5p might target four out of the five key DEGs in the AMD RPE.Conclusions:Based on our findings,HSP90AA1 is likely to be a central gene controlling the DNA replication and proteasome-mediated polyubiquitination during the RPE senescence observed in the progression of AMD.Targeting HSP90AA1,CHEK1,PSMA4,PSMD4,and/or PSMD8 genes through specific miRNAs or small molecules might potentially alleviate the progression of AMD展开更多
Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ...Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ctor treatment is likely to increase.In addition,current conventional treatment is only available for the late neovascular stage of age-related macular degeneration,and injections can come with potentially devastating complications,introducing the need for more economical and ris kfree treatment.In recent years,exosomes,which are nano-sized extracellular vesicles of an endocytic origin,have shown immense potential as diagnostic biomarkers and in the therapeutic application,as they are bestowed with characte ristics including an expansive cargo that closely resembles their parent cell and exceptional ability of intercellular communication and targeting neighboring cells.Exosomes are currently undergoing clinical trials for various conditions such as type 1 diabetes and autoimmune diseases;however,exosomes as a potential therapy for seve ral retinal diseases have just begun to undergo scrutinizing investigation with little literature on age-related macular degeneration specifically.This article will focus on the limited literature availa ble on exosome transplantation treatment in age-related macular degeneration animal models and in vitro cell cultures,as well as briefly identify future research directions.Current literature on exosome therapy using agerelated macular degeneration rodent models includes laser retinal injury,N-methyl-N-nitrosourea,and royal college of surgeon models,which mimic inflammatory and degenerative aspects of agerelated macular degeneration.These have shown promising results in preserving retinal function and morphology,as well as protecting photoreceptors from apoptosis.Exosomes from their respective cellular origins may also act by regulating the expression of various inflammatory cyto kines,mRNAs,and proteins involved in photo receptor degeneration pathways to exert a thera展开更多
AIM:To identify proangiogenic factors engaged in neovascular age-related macular degeneration(AMD)except vascular endothelial growth factor(VEGF)from human retinal pigment epithelial(h RPE)cells and investigate the un...AIM:To identify proangiogenic factors engaged in neovascular age-related macular degeneration(AMD)except vascular endothelial growth factor(VEGF)from human retinal pigment epithelial(h RPE)cells and investigate the underlying mechanisms.METHODS:VEGF receptor 2(VEGFR2)in ARPE-19 cells was depleted by si RNA transfection or overexpressed through adenovirus infection.The m RNA and the protein levels of interleukin-8(IL-8)in ARPE-19 cells were measured by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively.The protein levels of AKT,p-AKT,MEK,p-MEK,ERK1/2,p-ERK1/2,JNK,p-JNK,p38 and p-p38 were detected by Western blotting.A selective chemical inhibitor,LY3214996,was employed to inhibit phosphorylation of ERK1/2.Cell viability was determined by MTT assay.RESULTS:Knockdown of VEGFR2 in ARPE-19 cells robustly augmented IL-8 production at both the m RNA and the protein levels.Silencing VEGFR2 substantially enhanced phosphorylation of MEK and ERK1/2 while exerted no effects on phosphorylation of AKT,JNK and p38.Inhibiting ERK1/2 phosphorylation by LY3214996 reversed changes in VEGFR2 knockdown-induced IL-8 upregulation at the m RNA and the protein levels with no effects on cell viability.VEGFR2 overexpression significantly reduced IL-8 generation at the m RNA and the protein levels.CONCLUSION:Blockade of VEGF signaling augments IL-8 secretion via MEK/ERK1/2 axis and overactivation of VEGF pathway decreases IL-8 production in h RPE cells.Upregulated IL-8 expression after VEGF signaling inhibition in h RPE cells may be responsible for being incompletely responsive to anti-VEGF remedy in neovascular AMD,and IL-8 may serve as an alternative therapeutic target for neovascular AMD.展开更多
Age-related macular degeneration(AMD)causes irreversible blindness in people aged over 50 worldwide.The dysfunction of the retinal pigment epithelium is the primary cause of atrophic AMD.In the current study,we used t...Age-related macular degeneration(AMD)causes irreversible blindness in people aged over 50 worldwide.The dysfunction of the retinal pigment epithelium is the primary cause of atrophic AMD.In the current study,we used the ComBat and Training Distribution Matching method to integrate data obtained from the Gene Expression Omnibus database.We analyzed the integrated sequencing data by the Gene Set Enrichment Analysis.Peroxisome and tumor necrosis factor-α(TNF-α)signaling and nuclear factor kappa B(NF-κB)were among the top 10 pathways,and thus we selected them to construct AMD cell models to identify differentially expressed circular RNAs(circRNAs).We then constructed a competing endogenous RNA network,which is related to differentially expressed circRNAs.This network included seven circRNAs,15 microRNAs,and 82 mRNAs.The Kyoto Encyclopedia of Genes and Genomes analysis of mRNAs in this network showed that the hypoxia-inducible factor-1(HIF-1)signaling pathway was a common downstream event.The results of the current study may provide insights into the pathological processes of atrophic AMD.展开更多
Objective Age-related macular degeneration(AMD)is a degenerative retinal disease.The degeneration or death of retinal pigment epithelium(RPE)cells is implicated in the pathogenesis of AMD.This study aimed to activate ...Objective Age-related macular degeneration(AMD)is a degenerative retinal disease.The degeneration or death of retinal pigment epithelium(RPE)cells is implicated in the pathogenesis of AMD.This study aimed to activate the proliferation of RPE cells in vivo by using an adeno-associated virus(AAV)vector encodingβ-catenin to treat AMD in a mouse model.Methods Mice were intravitreally injected with AAV2/8-Y733F-VMD2-β-catenin for 2 or 4 weeks,andβ-catenin expression was measured using immunofluorescence staining,real-time quantitative reverse transcription polymerase chain reaction(PCR),and Western blotting.The function ofβ-catenin was determined using retinal flat mounts and laser-induced damage models.Finally,the safety of AAV2/8-Y733F-VMD2-β-catenin was evaluated by multiple intravitreal injections.Results AAV2/8-Y733F-VMD2-β-catenin induced the expression ofβ-catenin in RPE cells.It activated the proliferation of RPE cells and increased cyclin D1 expression.It was beneficial to the recovery of laser-induced damage by activating the proliferation of RPE cells.Furthermore,it could induce apoptosis of RPE cells by increasing the expression of Trp53,Bax and caspase3 while decreasing the expression of Bcl-2.Conclusion AAV2/8-Y733F-VMD2-β-catenin increasedβ-catenin expression in RPE cells,activated RPE cell proliferation,and helped mice heal from laser-induced eye injury.Furthermore,it could induce the apoptosis of RPE cells.Therefore,it may be a safe approach for AMD treatment.展开更多
Age-related macular degeneration(ARMD),one of the most common causes of blindness,should be considered more due to its exponential increase in the coming 20 years as a result of increasing the age of the population.Wh...Age-related macular degeneration(ARMD),one of the most common causes of blindness,should be considered more due to its exponential increase in the coming 20 years as a result of increasing the age of the population.Whereas more recent studies offered newer scaling systems for ARMD,traditionally it is classified as the early and late stages.The main injury in this disease occurred in retinal pigment epithelium(RPE)and the retina.RPE cells have a crucial role in hemostasis and supporting photoreceptors.In the early stages,damages to RPE are minimal and mainly no treatment is needed because most patients are asymptomatic.However,in the late stages,RPE impairment may lead to the invasion of choroidal vessels into the retina.Although anti-angiogenic agents can inhibit this abnormal growth of blood vessels,they cannot stop it completely,and finally,total loss of retinal cells may occur(geographical atrophy).Since this prevalent disease has not had any cure yet,the concept of substituting the RPE cells should be considered.Repairing the injury to central nervous system cells is almost impossible because the regenerative capacity of these cells is limited.Recently,the use of regenerative substitutes has been suggested to replace damaged tissues.Amniotic membrane(AM)has been raised as a suitable substitute for damaged RPE cells due to all of its unique properties:pluripotency,anti-angiogenic effect,and anti-inflammatory effect.Based on the few studies that have been published so far,it seems that the use of this membrane in the treatment of ARMD can be helpful,but more studies are needed.展开更多
AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides(LBP)against oxidative stress-induced apoptosis in human retinal pigment epithelial cells.METHODS: ARPE-19 cells, a human r...AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides(LBP)against oxidative stress-induced apoptosis in human retinal pigment epithelial cells.METHODS: ARPE-19 cells, a human retinal pigment epithelial cell lines, were exposed to different concentrations of H2O2 for 24h, then cell viability was measured by Cell Counting Kit-8(CCK-8) assay to get the properly concentration of H2O2 which can induce half apoptosis of APRE-19. With different concentrations of LBP pretreatment, the ARPE-19 cells were then exposed to appropriate concentration of H2O2, cell apoptosis was detected by flow cytometric analysis. Expression levels of Bcl-2 and Bax were measured by real time quantitative polymerase chain reaction(RT-PCR) technique.RSULTS: LBP significantly reduced the H2O2-induced ARPE-19 cells’ apoptosis. LBP inhibited the H2O2-induced down-regulation of Bcl-2 and up-regulation of Bax.CONCLUSION: LBP could protect ARPE-19 cells from H2O2-induced apoptosis. The Bcl-2 family had relationship with the protective effects of LBP.展开更多
基金supported by NIH/NEI R01 grants (EY031765,EY028100EY024963)+1 种基金BrightFocus Foundation,Research to Prevent Blindness Dolly Green Special Scholar AwardBoston Children’s Hospital Ophthalmology Foundation,Mass Lions Eye Research Fund Inc.(to JC)。
文摘Age-related macular degeneration is a primary cause of blindness in the older adult population. Past decades of research in the pathophysiology of the disease have resulted in breakthroughs in the form of anti-vascular endothelial growth factor therapies against neovascular age-related macular degeneration;however, effective treatment is not yet available for geographical atrophy in dry agerelated macular degeneration or for preventing the progression from early or mid to the late stage of age-related macular degeneration. Both clinical and experimental investigations involving human agerelated macular degeneration retinas and animal models point towards the atrophic alterations in retinal pigment epithelium as a key feature in age-related macular degeneration progression. Retinal pigment epithelium cells are primarily responsible for cellular-structural maintenance and nutrition supply to keep photoreceptors healthy and functional. The retinal pigment epithelium constantly endures a highly oxidative environment that is balanced with a cascade of antioxidant enzyme systems regulated by nuclear factor erythroid-2-related factor 2 as a main redox sensing transcription factor. Aging and accumulated oxidative stress triggers retinal pigment epithelium dysfunction and eventually death. Exposure to both environmental and genetic factors aggravates oxidative stress damage in aging retinal pigment epithelium and accelerates retinal pigment epithelium degeneration in age-related macular degeneration pathophysiology. The present review summarizes the role of oxidative stress in retinal pigment epithelium degeneration, with potential impacts from both genetic and environmental factors in age-related macular degeneration development and progression. Potential strategies to counter retinal pigment epithelium damage and protect the retinal pigment epithelium through enhancing its antioxidant capacity are also discussed, focusing on existing antioxidant nutritional supplementation, and exploring nuclear factor erythroid-2-relat
基金the National Natural Science Foundation of China(Grant Nos.81970821 and 82271100 to Q.L.).
文摘The retinal pigment epithelium(RPE)is fundamental to sustaining retinal homeostasis.RPE abnormality leads to visual defects and blindness,including age-related macular degeneration(AMD).Although breakthroughs have been made in the treatment of neovascular AMD,effective intervention for atrophic AMD is largely absent.The adequate knowledge of RPE pathology is hindered by a lack of the patients'RPE datasets,especially at the single-cell resolution.In the current study,we delved into a large-scale single-cell resource of AMD donors,in which RPE cells were occupied in a substantial proportion.Bulk RNA-seq datasets of atrophic AMD were integrated to extract molecular characteristics of RPE in the pathogenesis of atrophic AMD.Both in vivo and in vitro models revealed that carboxypeptidase X,M14 family member 2(CPXM2),was specifically expressed in the RPE cells of atrophic AMD,which might be induced by oxidative stress and involved in the epithelial-mesenchymal transition of RPE cells.Additionally,silencing of CPXM2 inhibited the mesenchymal phenotype of RPE cells in an oxidative stress cell model.Thus,our results demonstrated that CPXM2 played a crucial role in regulating atrophic AMD and might serve as a potential therapeutic target for atrophic AMD.
文摘Choroidal neovascularization characterizes wet age-related macular degeneration.Choroidal neovascularization formation involves a primarily angiogenic process that is combined with both inflammation and proteolysis.A primary cause of choroidal neovascularization pathogenesis is alterations in pro-and anti-angiogenic factors derived from the retinal pigment epithelium,with vascular endothelium growth factor being mainly responsible for both clinical and experimental choroidal neovascularization.MicroRNAs(miRNAs)which are short,non-coding,endogenous RNA molecules have a major role in regulating various pathological processes,including inflammation and angiogenesis.A review of recent studies with the mouse laser-induced choroidal neovascularization model has shown alterations in miRNA expression in choroidal neovascularization tissues and could be potential therapeutic targets for wet age-related macular degeneration.Upregulation of miR-505(days 1 and 3 post-laser),miR-155(day 14)occurred in retina;miR-342-5p(days 3 and 7),miR-126-3p(day 14)in choroid;miR-23a,miR-24,miR-27a(day 7)in retina/choroid;miR-505(days 1 and 3)in retinal pigment epithelium/choroid;downregulation of miR-155(days 1 and 3),miR-29a,miR-29b,miR-29c(day 5),miR-93(day 14),miR-126(day 14)occurred in retinal pigment epithelium/choroid.Therapies using miRNA mimics or inhibitors were found to decrease choroidal neovascularization lesions.Choroidal neovascularization development was reduced by overexpression of miR-155,miR-188-5p,miR-(5,B,7),miR-126-3p,miR-342-5p,miR-93,miR-126,miR-195a-3p,miR-24,miR-21,miR-31,miR-150,and miR-184,or suppression of miR-505,miR-126-3p,miR-155,and miR-23/27.Further studies are warranted to determine miRNA expression in mouse laser-induced choroidal neovascularization models in order to validate and extend the reported findings.Important experimental variables need to be standardized;these include the strain and age of animals,gender,number and position of laser burns to the eye,laser parameters to induce choroidal neovascu
基金supported by the Ministry of Science and Innovation of Spain,"Instituto de Salud CarlosⅢ","Fon do de Investigacion Sanitaria" (PI19/00265)funds FEDER"Una manera de hacer Europa" (to BM)。
文摘Age-related macular degeneration,a multifactorial inflammatory degenerative retinal disease,ranks as the leading cause of blindness in the elderly.Strikingly,there is a scarcity of curative therapies,especially for the atrophic advanced form of age-related macular degeneration,likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier,the prime to rget tissue of age-related macular degeneration.Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier,integrated by the dynamic interaction of the retinal pigment epithelium,the Bruch's membrane,and the underlying choriocapillaris.The Bruch's membrane provides structu ral and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier,and therefo re adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrie r.In the last years,advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials.This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healt hy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems.Then,we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling,discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.
文摘AIM: To evaluate the long-term anatomical and visual outcomes of drusenoid pigment epithelial detachment(D-PED) in intermediate age-related macular degeneration(AMD) eyes treated with 577 nm yellow subthreshold micropulse laser(SML).METHODS: In this retrospective study, 21 eyes of 16 patients with D-PED in intermediate AMD were consecutively included and assessed.All the eyes were treated with 577 nm SML in several sessions according to D-PED growth status.The logarithm of the minimum angle of resolution(logMAR) best-corrected visual acuity(BCVA) were assessed at the initial visit and after treatment.Spectral-domain optical coherence tomography(SD-OCT) was performed to evaluate the D-PED lifecycle by volumetric calculations.Regression analysis was used to determine the breakpoint, growth, and collapse rate of the D-PED lesions.The progression to advanced AMD was also documented.RESULTS: All the eyes were treated with SML for 2.9±1.0 sessions.The mean follow-up period was 25.3±12.6 mo.The BCVA was stable from the baseline to final visit.All the eyes were categorized into two groups according to the anatomical changes of the D-PED lesion: the collapse group(n=6, 28.6%) and non-collapse group(n=15, 71.4%).The change in logMAR BCVA did not differ significantly between the collapse group 0.00(-0.31, 0.85) and non-collapse group 0.00(0.00, 0.00;P=1).Regression analysis showed that the growth rate was significantly higher in the collapse group(0.090±0.095 mm;/mo) than in the non-collapse group(0.025±0.035 mm;/mo;P<0.001).One eye(4.8%) developed macular neovascularization at 11 mo after SML treatment in the non-collapse group.Three eyes(14.3%) developed geographic atrophy(GA) in the collapse group.CONCLUSION: Compared to the natural course of D-PED reported by previous studies, our results preliminarily show that SML can alleviate visual loss and possibility of progression to advanced AMD in eyes with D-PED in intermediate AMD.A controlled clinical trial needs to further verify the benefit of the intervention.
基金supported by grant from the National Natural Science Foundation of China(No.81670841).
文摘Background:Age-related macular degeneration(AMD)is the leading cause of vision loss worldwide.However,the mechanisms involved in the development and progression of AMD are poorly delineated.We aimed to explore the critical genes involved in the progression of AMD.Methods:The differentially expressed genes(DEGs)in AMD retinal pigment epithelial(RPE)/choroid tissues were identified using the microarray datasets GSE99248 and GSE125564,which were downloaded from the gene expression omnibus database.The overlapping DEGs from the two datasets were screened to identify DEG-related biological pathways using gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses.The hub genes were identified from these DEGs through protein-protein interaction network analyses.The expression levels of hub genes were evaluated by quantitative real-time polymerase chain reaction following the induction of senescence in ARPE-19 with FK866.Following the identification of AMD-related key genes,the potential small molecule compounds targeting the key genes were predicted by PharmacoDB.Finally,a microRNA-gene interaction network was constructed.Results:Microarray analyses identified 174 DEGs in the AMD RPE compared to the healthy RPE samples.These DEGs were primarily enriched in the pathways involved in the regulation of DNA replication,cell cycle,and proteasome-mediated protein polyubiquitination.Among the top ten hub genes,HSP90AA1,CHEK1,PSMA4,PSMD4,and PSMD8 were upregulated in the senescent ARPE-19 cells.Additionally,the drugs targeting HSP90AA1,CHEK1,and PSMA4 were identified.We hypothesize that Hsa-miR-16-5p might target four out of the five key DEGs in the AMD RPE.Conclusions:Based on our findings,HSP90AA1 is likely to be a central gene controlling the DNA replication and proteasome-mediated polyubiquitination during the RPE senescence observed in the progression of AMD.Targeting HSP90AA1,CHEK1,PSMA4,PSMD4,and/or PSMD8 genes through specific miRNAs or small molecules might potentially alleviate the progression of AMD
文摘Age-related macular degeneration is a major global cause of central visual impairment and seve re vision loss.With an aging population,the already immense economic burden of costly anti-vascular endothelial growth fa ctor treatment is likely to increase.In addition,current conventional treatment is only available for the late neovascular stage of age-related macular degeneration,and injections can come with potentially devastating complications,introducing the need for more economical and ris kfree treatment.In recent years,exosomes,which are nano-sized extracellular vesicles of an endocytic origin,have shown immense potential as diagnostic biomarkers and in the therapeutic application,as they are bestowed with characte ristics including an expansive cargo that closely resembles their parent cell and exceptional ability of intercellular communication and targeting neighboring cells.Exosomes are currently undergoing clinical trials for various conditions such as type 1 diabetes and autoimmune diseases;however,exosomes as a potential therapy for seve ral retinal diseases have just begun to undergo scrutinizing investigation with little literature on age-related macular degeneration specifically.This article will focus on the limited literature availa ble on exosome transplantation treatment in age-related macular degeneration animal models and in vitro cell cultures,as well as briefly identify future research directions.Current literature on exosome therapy using agerelated macular degeneration rodent models includes laser retinal injury,N-methyl-N-nitrosourea,and royal college of surgeon models,which mimic inflammatory and degenerative aspects of agerelated macular degeneration.These have shown promising results in preserving retinal function and morphology,as well as protecting photoreceptors from apoptosis.Exosomes from their respective cellular origins may also act by regulating the expression of various inflammatory cyto kines,mRNAs,and proteins involved in photo receptor degeneration pathways to exert a thera
基金Supported by the National Natural Science Foundation of China(No.81200670)。
文摘AIM:To identify proangiogenic factors engaged in neovascular age-related macular degeneration(AMD)except vascular endothelial growth factor(VEGF)from human retinal pigment epithelial(h RPE)cells and investigate the underlying mechanisms.METHODS:VEGF receptor 2(VEGFR2)in ARPE-19 cells was depleted by si RNA transfection or overexpressed through adenovirus infection.The m RNA and the protein levels of interleukin-8(IL-8)in ARPE-19 cells were measured by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay respectively.The protein levels of AKT,p-AKT,MEK,p-MEK,ERK1/2,p-ERK1/2,JNK,p-JNK,p38 and p-p38 were detected by Western blotting.A selective chemical inhibitor,LY3214996,was employed to inhibit phosphorylation of ERK1/2.Cell viability was determined by MTT assay.RESULTS:Knockdown of VEGFR2 in ARPE-19 cells robustly augmented IL-8 production at both the m RNA and the protein levels.Silencing VEGFR2 substantially enhanced phosphorylation of MEK and ERK1/2 while exerted no effects on phosphorylation of AKT,JNK and p38.Inhibiting ERK1/2 phosphorylation by LY3214996 reversed changes in VEGFR2 knockdown-induced IL-8 upregulation at the m RNA and the protein levels with no effects on cell viability.VEGFR2 overexpression significantly reduced IL-8 generation at the m RNA and the protein levels.CONCLUSION:Blockade of VEGF signaling augments IL-8 secretion via MEK/ERK1/2 axis and overactivation of VEGF pathway decreases IL-8 production in h RPE cells.Upregulated IL-8 expression after VEGF signaling inhibition in h RPE cells may be responsible for being incompletely responsive to anti-VEGF remedy in neovascular AMD,and IL-8 may serve as an alternative therapeutic target for neovascular AMD.
基金funded by the National Natural Science Foundation of China(Grant No.81970821)the Postgraduate Research Innovation Program of Jiangsu Provinc(Grant No.SJCX21_0624).
文摘Age-related macular degeneration(AMD)causes irreversible blindness in people aged over 50 worldwide.The dysfunction of the retinal pigment epithelium is the primary cause of atrophic AMD.In the current study,we used the ComBat and Training Distribution Matching method to integrate data obtained from the Gene Expression Omnibus database.We analyzed the integrated sequencing data by the Gene Set Enrichment Analysis.Peroxisome and tumor necrosis factor-α(TNF-α)signaling and nuclear factor kappa B(NF-κB)were among the top 10 pathways,and thus we selected them to construct AMD cell models to identify differentially expressed circular RNAs(circRNAs).We then constructed a competing endogenous RNA network,which is related to differentially expressed circRNAs.This network included seven circRNAs,15 microRNAs,and 82 mRNAs.The Kyoto Encyclopedia of Genes and Genomes analysis of mRNAs in this network showed that the hypoxia-inducible factor-1(HIF-1)signaling pathway was a common downstream event.The results of the current study may provide insights into the pathological processes of atrophic AMD.
基金supported by the National Natural Science Foundation of China(No.61675226).
文摘Objective Age-related macular degeneration(AMD)is a degenerative retinal disease.The degeneration or death of retinal pigment epithelium(RPE)cells is implicated in the pathogenesis of AMD.This study aimed to activate the proliferation of RPE cells in vivo by using an adeno-associated virus(AAV)vector encodingβ-catenin to treat AMD in a mouse model.Methods Mice were intravitreally injected with AAV2/8-Y733F-VMD2-β-catenin for 2 or 4 weeks,andβ-catenin expression was measured using immunofluorescence staining,real-time quantitative reverse transcription polymerase chain reaction(PCR),and Western blotting.The function ofβ-catenin was determined using retinal flat mounts and laser-induced damage models.Finally,the safety of AAV2/8-Y733F-VMD2-β-catenin was evaluated by multiple intravitreal injections.Results AAV2/8-Y733F-VMD2-β-catenin induced the expression ofβ-catenin in RPE cells.It activated the proliferation of RPE cells and increased cyclin D1 expression.It was beneficial to the recovery of laser-induced damage by activating the proliferation of RPE cells.Furthermore,it could induce apoptosis of RPE cells by increasing the expression of Trp53,Bax and caspase3 while decreasing the expression of Bcl-2.Conclusion AAV2/8-Y733F-VMD2-β-catenin increasedβ-catenin expression in RPE cells,activated RPE cell proliferation,and helped mice heal from laser-induced eye injury.Furthermore,it could induce the apoptosis of RPE cells.Therefore,it may be a safe approach for AMD treatment.
文摘Age-related macular degeneration(ARMD),one of the most common causes of blindness,should be considered more due to its exponential increase in the coming 20 years as a result of increasing the age of the population.Whereas more recent studies offered newer scaling systems for ARMD,traditionally it is classified as the early and late stages.The main injury in this disease occurred in retinal pigment epithelium(RPE)and the retina.RPE cells have a crucial role in hemostasis and supporting photoreceptors.In the early stages,damages to RPE are minimal and mainly no treatment is needed because most patients are asymptomatic.However,in the late stages,RPE impairment may lead to the invasion of choroidal vessels into the retina.Although anti-angiogenic agents can inhibit this abnormal growth of blood vessels,they cannot stop it completely,and finally,total loss of retinal cells may occur(geographical atrophy).Since this prevalent disease has not had any cure yet,the concept of substituting the RPE cells should be considered.Repairing the injury to central nervous system cells is almost impossible because the regenerative capacity of these cells is limited.Recently,the use of regenerative substitutes has been suggested to replace damaged tissues.Amniotic membrane(AM)has been raised as a suitable substitute for damaged RPE cells due to all of its unique properties:pluripotency,anti-angiogenic effect,and anti-inflammatory effect.Based on the few studies that have been published so far,it seems that the use of this membrane in the treatment of ARMD can be helpful,but more studies are needed.
基金Supported by National Basic Research Program of China(973 program,No.2011CB707501)the Natural Science Foundation of Guangdong Province(No.S2013010016037)
文摘AIM: To investigate the protective effect and its mechanism of lycium barbarum polysaccharides(LBP)against oxidative stress-induced apoptosis in human retinal pigment epithelial cells.METHODS: ARPE-19 cells, a human retinal pigment epithelial cell lines, were exposed to different concentrations of H2O2 for 24h, then cell viability was measured by Cell Counting Kit-8(CCK-8) assay to get the properly concentration of H2O2 which can induce half apoptosis of APRE-19. With different concentrations of LBP pretreatment, the ARPE-19 cells were then exposed to appropriate concentration of H2O2, cell apoptosis was detected by flow cytometric analysis. Expression levels of Bcl-2 and Bax were measured by real time quantitative polymerase chain reaction(RT-PCR) technique.RSULTS: LBP significantly reduced the H2O2-induced ARPE-19 cells’ apoptosis. LBP inhibited the H2O2-induced down-regulation of Bcl-2 and up-regulation of Bax.CONCLUSION: LBP could protect ARPE-19 cells from H2O2-induced apoptosis. The Bcl-2 family had relationship with the protective effects of LBP.
