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Objective To investigate the efficacy and safety of subretinal fluid extraction combined with intravitreal conbercept and gas injection in treating polypoidal choroidal vasculopathy(PCV)complicated with serous retinal pigment epithelium detachment(sPED).Methods From July 2019 to February 2021,13 patients(13 eyes)with PCV complicated with sPED who were treated with subretinal fluid extraction combined with intravitreal injection of conbercept and gas in the Weifang Eye Hospital were selected.All affected eyes received at least 3 times(once a month)of intravitreal anti-vas-cular endothelial growth factor(VEGF)(ranibizumab)injections before the surgery,and the treatment was ineffective.The changes in best corrected visual acuity(BCVA),central retinal thickness(CRT),macular foveal PED height and width before and 1 week,1 month,3 months and 6 months after the operation were observed,and the intraoperative and postop-erative complications were recorded.Results The BCVA of the affected eyes 1 week after operation was better than that before operation,and the difference was statistically significant(Z=-3.237,P=0.001).The CRT of the affected eyes at 1 week,1 month,3 months and 6 months after the operation were thinner than that before the operation,and the differ-ence was statistically significant(Z=-3.180,-3.180,-3.110 and-3.180,P=0.001,0.001,0.002 and 0.001).The height and width of PED at 1 week,1 month,3 months and 6 months after the operation were lower than those before the operation,and the differences were statistically significant(all P＜0.05).Thirteen eyes received an average of(4.15±1.40)intravitreal injections(ranibizumab)before the surgery,and the treatment duration was(5.92±3.95)months(equivalent to one injection every 6 weeks).During the 6-month follow-up,13 eyes received an average of(2.31±1.97)intravitreal injections(conbercept)(equivalent to once every 10 weeks).Partial correlation analysis showed a weak positive correla-tion between the increase in BCVA and the decrease in CRT 6 months after operation(r=0.416,P=0.203).There was no significant correlation between the increase in BCVA and the changes in PED height and width 6 months after operation(r=0.218,0.209,P=0.520,0.538).At 1 month after the operation,9 eyes had PED recurrence or different degrees of retinal nerve subepithelial effusion,and PED improved after repeated intravitreal injection of conbercept.At 6 months after opera-tion,subfoveal PED completely disappeared in 3 eyes,and the retina was completely reattached.There was still active exu-dation in the retina of 1 eye.No systemic or severe ocular complications occurred in 13 eyes during the follow-up period.Conclusion Subretinal fluid extraction combined with intravitreal injection of conbercept and gas in the treatment of PCV complicated with sPED can safely and effectively reduce CRT,improve PED,and reduce the damage to the retina caused by long-term PED,but it has no significant effect on the improvement of BCVA at 6 months after the operation.
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Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly worldwide and is characterized by degeneration of the photoreceptor, retinal pigment epithelium, Bruch membrane and choriocapillaris complex.Impairment of RPE cell function is an early and critical event in the molecular pathways leading to clinically relevant AMD changes.Programmed cell death (PCD) plays an important role in response to stress and regulation of homeostasis and disease.In recent years, multiple studies have shown that apoptosis, pyroptosis, necroptosis and ferroptosis are likely involved in RPE cell PCD and correlate with the onset and development of AMD.There may be interaction or synergy between the various death pathways.This article reviewed the pathogenic mechanism of apoptosis, pyroptosis, necroptosis and ferroptosis in retinal pigment epithelial cell and their research progress in AMD, which might provide new approaches for the prevention and treatment of AMD.
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Laser-induced retinal damage is a gradual and progressive process, yet there remains a dire need for safe and effective therapeutic drugs and preventive measures to mitigate and treat this condition. Currently, the exploration of treatment options for laser-induced retinal damage is still in its experimental phase. This review delves into the histopathological, functional, and molecular expression levels of the retina after acute laser injury. It aims to uncover the acute changes that occur following laser injury, identify the optimal window period for intervention, and hypothesize the best time for treatment to rescue residual cells and preserve remaining vision.
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Age-related macular degeneration(ARMD)is a neurodegenerative disease associated with oxidative stress. It is characterized by progressive death of photoreceptors and retinal pigment epithelium(RPE), and is one of the leading causes of irreversible loss of central vision in patients over the age of 65 years old. MicroRNA(miRNA)is a class of regulatory short-chain non-coding RNA that can bind and inhibit multiple gene targets in the same biological pathway. This unique property makes microRNA an ideal target for exploring the pathogenesis, diagnosis and treatment of non-exudative ARMD. Previous studies have found that the pathogenesis of non-exudative ARMD involves age, genetics, environment, oxidative stress, lipid metabolism, autophagy and immunity. However, the exact mechanisms have not been fully clarified. As biomarkers of non-exudative ARMD, miRNA play a role in oxidative stress and lipid metabolism. This article summarizes the role of various miRNA in targeting Nrf2 and HIF-1α to inhibit hypoxia-related angiogenesis signaling, thereby affecting oxidative stress. Additionally, miRNA regulate lipid uptake and the expression of ABCA1 in RPE and macrophages, thereby influencing lipid metabolism. This deepens the understanding of the role of miRNA in oxidative stress and lipid metabolism in non-exudative ARMD, and provides directions for further improving the understanding of the pathogenesis and prevention of non-exudative ARMD.
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Central serous chorioretinopathy(CSC)is a common macular degeneration that primarily affects young patients. While the disease may resolve on its own to some extent, delayed or inadequate treatment can result in recurrence and progression to chronic CSC. This can lead to complications such as retinal pigment epithelium(RPE)atrophy and choroidal neovascularization, ultimately causing irreversible damage to central vision. Subthreshold micropulse laser photocoagulation(SMLP)is a type of laser therapy that differs from traditional lasers in that it does not cause damage or thermal injury to RPE cells and photoreceptors. SMLP has become widely used in clinical treatment of CSC due to its effectiveness, safety, and reproducibility, particularly in cases where verteporfin is not available in photodynamic therapy(PDT). The purpose of this review is to explain the mechanism of SMLP in CSC and summarize the effector cells, cytokines, and mechanisms of action involved in its treatment. This will provide a theoretical basis for promoting and rationalizing the use of SMLP in clinical practice.
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Age-related macular degeneration(ARMD)is the leading cause of blindness in the elderly. Studies have shown that the regulation disorder of extracellular matrix(ECM)is one of the important characteristics of ARMD, and its damage can be sustained throughout the disease course. Additionally, various cell types participate in the formation and abnormal deposition of ECM under the control of multiple signals. Subsequently, they transmit signals that regulate adhesion, migration, proliferation, apoptosis, survival or differentiation, which lead to the destruction of the retinal and choroidal microenvironment, immune dysfunction, infiltrative inflammatory cell differentiation, neovascularization and epithelial mesenchymal transformation, and ultimately lead to subretinal fibrosis, scarring and severe visual impairment in advanced ARMD. Therefore, increasing attention has been paid to the role of ECM in ARMD in recent years. This article reviews the relationship between retinal ECM and ARMD and the role between ECM and various types of cells in ARMD, hoping to provide guidance for the research direction of ARMD treatment.
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AIM: To observe the multimodal imaging characteristics of Best vitelliform macular dystrophy(BVMD).METHODS:The clinical data of 30 patients(60 eyes)diagnosed as BVMD at stage Ⅰ to Ⅳ in Nanjing Medical University Affiliated Eye Hospital from June 2016 to October 2022 were collected for a retrospective analysis, and all patients are binocular involved. All patients underwent best corrected visual acuity(BCVA), slit lamp microscopy, indirect ophthalmoscopy, intraocular pressure, fundus photography, spectral-domain optical coherence tomography(SD-OCT), fundus autofluorescence(FAF), fundus fluorescein angiography(FFA), electro-oculogram(EOG)and optical coherence tomography angiography(OCTA).RESULTS: A total of 30 patients(60 eyes)were included, with 8 eyes at stage Ⅰ, 24 eyes at stage Ⅱ, 22 eyes at stage Ⅲ and 6 eyes at stage Ⅵ. The imaging characteristics of fundus photography, FAF, FFA and SD-OCT were basically consistent with previous literature reports. EOG showed Arden ratio <1.55. OCTA could detect early lesions, observe the location of vitelliform substance, external segment of photoreceptor, fluid and choroidal neovascularization(CNV).CONCLUSION: Multimodal imaging assisted in diagnosing BVMD, reducing missed diagnosis and misdiagnosis, among which OCTA had significant advantages over other examinations, and fast and non-invasive were its biggest advantages.
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Abstract Henrik and Torsten Sjögren (/'ogrƏn/ or SHOH-grƏn) were two Swedish physicians living in the same period, but completely unrelated, except for their notable contributions to Medicine. The first one described keratoconjunctivitis sicca, afterward called Sjögren's syndrome, and a fishing net aspect retinal pigmentation affecting visual acuity, nowadays known as Sjögren reticular dystrophy. The last one contributed to the understanding of Spielmeyer-Sjögren disease, Marinesco-Sjögren, and Sjögren-Larsson syndromes, all related to genetic disorders and neurological symptoms. In this paper, we aim to describe each disorder, in order to avoid any misunderstanding in diagnosis and for historical record.
Resumo Henrik e Torsten Sjögren (/'ogrƏn/ or SHOH-grƏn) foram dois médicos suecos que viveram na mesma época, mas não tinham nenhuma relação entre si, exceto por suas notáveis contribuições à medicina. O primeiro descreveu a ceratoconjuntivite sicca, posteriormente chamada de síndrome de Sjögren, e uma pigmentação da retina com aspecto de rede de pesca que afeta a acuidade visual, hoje conhecida como distrofia reticular de Sjögren. O último contribuiu para a compreensão da doença de Spielmeyer-Sjögren, das síndromes de Marinesco-Sjögren e Sjögren-Larsson, todas relacionadas a distúrbios genéticos e sintomas neurológicos. Neste artigo, pretendemos descrever cada desordem, a fim de evitar qualquer mal-entendido no diagnóstico e para registro histórico.
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ABSTRACT We report the case of a 39-year-old male patient who presented with visual loss in the right eye for 6 weeks. The best-corrected visual acuity was counting fingers in the right eye and 20/30 in the left eye. The fundus examination demonstrated a right retinal detachment inferiorly extending to the fovea and a left macular serous detachment. After multimodal imaging study, the patient was diagnosed as having a bullous variant of central serous chorioretinopathy and treated with oral spironolactone associated with adjuvant laser photocoagulation. The retinal changes resolved after 6 months. The final visual acuity was 20/20 in both eyes.
RESUMO Relatamos o caso de um homem de 39 anos apresentando perda visual no olho direito há seis semanas. A melhor acuidade visual corrigida foi conta-dedos no olho direito e 20/30 no esquerdo. A fundoscopia demonstrou descolamento de retina direito inferiormente com extensão à fóvea e descolamento macular seroso à esquerda. Após estudos de imagem multimodal, o paciente foi diagnosticado com uma variante bolhosa de coriorretinopatia serosa central e tratado com espironolactona oral associada à fotocoagulação a laser adjuvante. As alterações retinianas resolveram após seis meses. A acuidade visual final foi 20/20 em ambos os olhos.
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Age-related macular degeneration(AMD)is a common eye disease causing irreversible visual impairment in the elderly. The tight junction(TJ)between retinal pigment epithelium cells(RPECs)is an important structural unit of the outer blood retinal barrier(oBRB). The TJ is defective in the pathogenesis of AMD, which in turn promotes the destruction of oBRB and accelerates the occurrence and progression of AMD. In this paper, the roles of TJ and TJ protein in maintaining oBRB function, TJ protein abnormality and oBRB destruction in the pathogenesis of AMD were reviewed, aiming to provide new ideas for the treatment of AMD.
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AIM: To observe the effects and mechanisms of ferroptosis on high glucose(HG)-induced retinal pigment epithelium(RPE)cells injury, and to provide new ideas for the treatment of diabetic retinopathy(DR).METHODS: The ARPE-19 cell lines cultured in vitro were divided into normal control group(NC group), high glucose group(HG group), and high glucose+Ferrostatin-1 group(Fer-1 group). The cell viability of each group was detected by CCK-8 assay. The expressions of interleukin 6(IL-6), IL-1β and monocyte chemotactic protein-1(MCP-1)were detected using ELISA kits. The levels of malondialdehyde(MDA), glutathione(GSH), glutathione peroxidase 4(GPX4)and iron content were detected using the corresponding assay kits. The mitochondrial changes in ARPE-19 cells were observed by transmission electron microscopy. The expressions of ferroptosis-related proteins including long-chain lipoyl CoA synthase 4(ACSL4)and GPX4, as well as vascular endothelial growth factor(VEGF)were detected by Western blotting and immunofluorescence staining.RESULTS: Compared with NC group, the cell viability of HG group decreased significantly, the expression levels of inflammatory factors in cell supernatant increased, the contents of MDA and iron significantly increased, GSH and GPX4 significantly decreased(all P<0.01), the mitochondria of ARPE-19 cells shrunk, the expression of proteins ACSL4 and VEGF increased, while the expression of GPX4 decreased(all P<0.01). Compared with HG group, the cell viability of Fer-1 group significantly increased, the expression levels of inflammatory factors in cell supernatant decreased, MDA and iron contents significantly decreased, GSH contents and GPX4 viability significantly increased(all P<0.05), the morphology of mitochondria in ARPE-19 cells improved, the expression of ACSL4 and VEGF decreased, while the expression of GPX4 increased(all P<0.05).CONCLUSION: Ferroptosis is involved in the injury of RPE induced by HG. Inhibiting ferroptosis can improve cell viability, reduce inflammation and oxidative stress, and alleviate HG-induced RPE cells injury.
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Objective To investigate the action mechanism of cyclic RNA0001287(circ_0001287)and miR-21 in the pathogenesis of diabetic retinopathy(DR).Methods Primary human retinal pigment epithelium(phRPE)cells were iso-lated for circRNA microarray analysis.Arising retinal pigment epithelium(ARPE)-19 cells were cultured in vitro and divid-ed into the blank group,high-glucose group,negative group,si-circ group,circ_0001287 group,circ_0001287+negative group,and circ_0001287+miR-21 group.Small interfering RNA(siRNA)oligonucleotides against circ_0001287,mimics containing miR-21 sequences and miR-21 mimic plasmids were constructed.In the negative group,si-circ group,circ_0001287 group,circ_0001287+negative group and circ_0001287+miR-21 group,the empty plasmid,circ_0001287 siRNA,circ_0001287 mimics,circ_0001287 mimics+miRNA disordered sequence,and circ_0001287 mimics+miR-21 mimic plasmid were transfected into ARPE-19 cells using Lipofectamine 2000 Transfection Reagent.After transfection for 6 h,the Opti-MEM medium was replaced with a fresh normal medium.Cells in the blank group and the high-glucose group were not transfected.Cells in the blank group were cultured with culture solution containing 5.5 mmol·L-1 glucose,and cells in the high-glucose group were cultured with culture solution containing 15.5 mmol·L-1,25.5 mmol·L-1 and 35.5 mmol·L-1 glucose,respectively.Cells in other groups were treated with 35.5 mmol·L-1 glucose for 48 h.The expressions of circ_0001287 and miR-21 were detected by reverse transcription polymerase chain reaction(RT-PCR),cell proliferation activity was detected by Cell Counting Kit-8,and the targeting relationship between circ_0001287 and miR-21 was detected by Dual Luciferase Reporter Assay.RNA immunoprecipitation(RIP)assay and biotin-coupled probe pull-down assay were used to verify the targeting relationship between circ_0001287 and miR-21.Western blot was used to detect protein expression.Re-sults After screening by circRNA,the expression of hsa_circ_0001287 in phRPE cells was significantly reduced.RT-PCR detection showed that compared with the blank group,circ_0001287 expression in ARPE-19 cells in the high-glucose group decreased(P＜0.05)in a dose-dependent manner,and miR-21 expression in ARPE-19 cells gradually increased with the in-crease of glucose concentration(P＜0.05).After co-transfection of siRNA with circ_0001287 mimics,siRNA also reduced circ_0001287 expression,and the relative expression of circ_0001287 in the circ_0001287+negative group(0.70±0.03)was significantly lower than that in the negative group(0.98±0.04,P＜0.05).For cells transfected with the circ_0001287-WT plasmid,compared with the control simulation group(0.98±0.03),the relative luciferase activity of the miR-21 simulation group(0.59±0.02)decreased(P＜0.05).However,for cells transfected with circ_0001287-MUT plasmid,the relative ac-tivity of luciferase was almost the same in the control simulation group(0.96±0.05)and the miR-21 simulation group(1.00±0.04,P＞0.05).In the anti-Ago RIP experiment,miR-21 was significantly enriched in the circ_0001287 group com-pared with the control group,indicating that miR-21 could be significantly pulled down by the biotinylated circ_0001287 probe.Pull-down analysis demonstrated that compared with the control IgG,circ_0001287 specific probe pull-down sam-ples showed significant enrichment of circ_0001287 and miR-21.In this experiment,the cell proliferation rate of the circ_0001287+miR-21 group(78.25％±3.01％)was lower than that of the circ_0001287+negative group(90.88％±3.51％,P＜0.05).Compared with the blank group,the expression of PTEN protein in ARPE-19 cells in the high-glucose group treated with 35.5 mmol·L-1 glucose was significantly down-regulated(P＜0.05),the expression of PTEN protein in ARPE-19 cells in the circ_0001287 group was higher than that in the negative group(P＜0.05),and the expression of PTEN protein in ARPE-19 cells in the circ_0001287+miR-21 group was higher than that in the circ_0001287 group(P＜0.05).Conclusion The expression of circ_0001287 is down-regulated in phRPE cells and high-glucose induced ARPE-19 cells,and up-regulated circ_0001287 can inhibit the injuiy of diabetic RPE cells by adsorption of miR-21 and activation of PTEN expression.
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Objective:To investigate the effect of microRNA-27b-3p (miR-27b-3p)/nuclear factor-E2-related factor 2 (Nrf2) on metabolic memory impairment of human retinal pigment epithelial (RPE) cells and to explore its regulatory mechanism.Methods:ARPE-19 cells were divided into normal control group, metabolic memory group, miR-27b-3p control group, miR-27b-3p inhibitor group, and liraglutide group.Cells in normal control group were cultured in 5.5 mmol/L normal glucose medium for 6 days.Cells in metabolic memory group were cultured in 30 mmol/L glucose for 3 days and changed to 5.5 mmol/L for 3 days.Cells in miR-27b-3p inhibitor group were added with puromycin after lentiviral transfection to select the successfully transfected cells, and were cultured in 30 mmol/L glucose for 3 days then 5.5 mmol/L glucose for 3 days.Cells in liraglutide group were cultured in 30 mmol/L glucose with liraglutide for 3 days then 5.5 mmol/L glucose for 3 days.The regulatory relationship between miR-27b-3p and Nrf2 was verified by lentiviral transfection.Expressions of miR-27b-3p, Nrf2, NAD(P)H dehydrogenase[quinone]1 (NQO1), heme oxygenase-1 (HO-1) mRNA and protein levels were analyzed by real-time quantitative PCR.Total and nuclear Nrf2 protein expressions were detected by Western blot.The cell proliferation rates of various groups were determined by cell counting kit-8 (CCK-8).The reactive oxygen species (ROS) level was detected by the DHE kit.Results:The miR-27b-3p mRNA relative expression of normal control group, metabolic memory group, miR-27b-3p control group, miR-27b-3p inhibitor group was 1.000±0.000, 1.881±0.034, 1.683±0.088 and 0.111±0.008, respectively, with a statistically significant difference ( F=850.815, P<0.001).The miR-27b-3p mRNA relative expression level was lower in normal control group than in metabolic memory group, lower in miR-27b-3p inhibitor group than in normal control group, and the differences were statistically significant (both at P<0.01).The expression levels of Nrf2 mRNA, total protein, and nuclear protein were decreased in metabolic memory group in comparison with normal control group and were significantly increased in miR-27b-3p inhibitor group in comparison with miR-27b-3p control group, showing statistically significant differences (all at P<0.01).The NQO1 and HO-1 mRNA expressions were decreased in metabolic memory group in comparison with normal control group, and were significantly higher in miR-27b-3p inhibitor group compared with miR-27b-3p control group, showing statistically significant differences (all at P<0.01).The fluorescence intensity of Nrf2, NQO1, and HO-1 was lower in metabolic memory group than in normal control group, and was higher in miR-27b-3p inhibitor group than in miR-27b-3p control group, showing statistically significant differences (all at P<0.01).Compared with metabolic memory group, the relative expression of miR-27b-3p mRNA declined in liraglutide group, with a statistically significant difference ( P<0.05).The relative expression levels of Nrf2 mRNA, NQO1 mRNA, HO-1 mRNA, total and nuclear Nrf2 protein of liraglutide group were enhanced in comparison with metabolic memory group, with statistically significant differences (all at P<0.05).The fluorescence intensity of Nrf2, NQO1, and HO-1 was enhanced in liraglutide group in comparison with metabolic memory group, and the differences were statistically significant (all at P<0.05).Compared with normal control group and liraglutide group, the cell proliferation viability was decreased in metabolic memory group, and the differences were statistically significant (both at P<0.01).The relative content of ROS was higher in metabolic memory group than in normal control group and liraglutide group, and the difference was significant (all at P<0.01). Conclusions:Liraglutide reverses the inhibition of metabolic memory on Nrf2, NQO1, and HO-1 by downregulating miR-27b-3p.
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With the popularity of electronic devices and the increasing environmental light pollution, more attention has been paid to the damage caused by retinal light irradiation and its pathogenic effects in retinal pigment degeneration, age-related macular degeneration and other diseases.The types of light-retinal tissue reaction are mainly photothermal and photochemical, and the photochemical reaction produced by visible light is closely related to retinal diseases.The parameters of light irradiation include wavelength, energy density and duration, etc.The effect of light irradiation on retinal cells can be influenced by many external factors under different parameters.Many in vitro models of light irradiation on retinal cells have been established to study the mechanism of light irradiation, especially blue light on retinal pigment epithelial cells, photoreceptor cells and nerve cells.Light irradiation can cause oxidative stress, endoplasmic reticulum stress and mitochondrial damage in retinal cells, which activates autophagy and regulates apoptosis.Inflammasome activation and exosomes are also involved in the regulation of light-induced damage to retinal pigment epithelial cells.There are also studies on the potential therapeutic effect of different wavelength light sources on cells.This review discusses the differences in cellular and light irradiation parameters between different models with respect to experimental models of retinal light irradiation in terms of types of light-retinal tissue responses, light irradiation parameters commonly used in biological studies, and retinal pigment epithelium light irradiation models, retinal photoreceptor light irradiation models, and retinal ganglion cell light irradiation models.
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Objective:To observe the effect of the antioxidant N-acetylcysteine (NAC) and selective endoplasmic reticulum stress response inhibitor salubrinal on the apoptosis of retinal pigment epithelial cells induced by all-trans-retinoic acid (ATRA).Methods:Human ARPE-19 cell line was used as the experimental cell line, and was divided into normal control group cultured with complete medium, model control group cultured with complete medium containing 10 μmol/L ATRA, NAC treatment group cultured with complete medium containing 10 μmol/L ATRA+ 5 mmol/L NAC, salubrinal group cultured with complete medium containing 10 μmol/L ATRA+ 40 μmol/L salubrinal, NAC+ salubrinal group cultured with complete medium containing 10 μmol/L ATRA+ 5 mmol/L NAC+ 40 μmol/L salubrinal.After 24-hour culture, apoptosis rate, multicaspase level and reactive oxygen species (ROS) level of ARPE-19 cells were detected by flow cytometry.The expressions of vascular endothelial growth factor A (VEGF-A), C/EBP-homologous protein (CHOP), cleaved-caspase 3 in cells were detected by Western blot.Results:There were significant differences in the apoptosis rate, multicaspase and ROS levels among the five groups ( F=113.23, 602.41, 160.39; all at P<0.001). The apoptosis rate, multicaspase and ROS levels of normal control group, NAC treatment group, salubrinal group and NAC+ salubrinal group were significantly lower than those of model control group (all at P<0.05). There were significant differences in the expression levels of VEGF-A, CHOP and cleaved-caspase 3 among the five groups ( F=24.62, 36.35, 60.25; all at P<0.001). The protein expression levels of VEGF-A, CHOP and cleaved-caspase 3 of normal control group, NAC treatment group, salubrinal group and NAC+ salubrinal group were significantly lower than those of model control group (all at P<0.05). Conclusions:ATRA can induce RPE cells to produce oxidative stress and endoplasmic reticulum stress injury, which leads to apoptosis.NAC and salubrinal can effectively reduce the RPE cell apoptosis by inhibiting stress response.
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Objective:To observe the inhibition of SARS-CoV-2 spike protein (S-protein) on the proliferation of human retinal pigment epithelium (RPE) cells.Methods:SARS-CoV-2 S-protein gene fragment expression plasmid (p3xflag-S) was constructed and transfected into human RPE, HEK293 cells. DNA sequencing was used for identification, and the expression of Flag-S was detected by Western blot. HEK293 cells were divided into the cells 1, 2, 3 and 4 and transfected with GFP11 plasmid and vector, GFP1-10 plasmid and vector, transfected with GFP11 and pCMV-HA-ACE2 plasmid, GFP1-10 and p3xflag-S plasmid. Cell 1 was co-cultured with cell 2 (control group 1), cell 2 with cell 3 (control group 2), cell 3 with cell 4 (observation group), and cell 1 mixed with cells 2, 3 and 4 (control group 3). Bright-field microscopy and fluorescence microscopy were used to observe cell fusion. RPE cells were divided into control group and overexpression S-protein group. The cell cycle was detected by flow cytometry; the cell proliferation level was detected by Counting Kit 8 (CCK-8); and the S-protein expression level in RPE cells was detected by Western blot. The Student’s t-test was performed for comparison between groups. Results:DNA sequence assay showed that S-protein cDNA was fused with flag-tagged protein. Western blot assay showed that S-protein-related expression was elevated in transfected HEK293 cells compared with untransfected p3xflag-S cells. Large, multinucleated fused cell clusters were visible under bright-field microscopy; multiple nuclear with distinct green fluorescence were visible in the fused cells under fluorescence microscopy. Western blot assay showed elevated S-protein-related expression in transfected p3xflag-S plasmid RPE cells compared to untransfected p3xflag-S plasmid RPE cells. CCK-8 results showed that the proliferative capacity of RPE cells in the S-protein overexpression group was significantly reduced compared with the control group, with statistically significant differences ( t=22.70, 16.75, 23.38; P<0.000 1). The results of flow cytometry showed that the G1 phase cells in the control and overexpression S-protein groups were 41.1 % and 67.0%, respectively; compared with the control group, the G1 phase cells in the overexpression S-protein group were significantly higher, and the difference was statistically significant ( t=4.76, P=0.018). The apoptosis rate was significantly increased in the S-protein overexpression group compared with the control group, and the difference was statistically significant ( t=4.91, P=0.008). Conclusion:Overexpression of the SARS-CoV-2 spike protein reduced the proliferation of human RPE cells.
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AIM: To investigate the occurrence and possible mechanism of blue light-induced ferroptosis in retinal pigment epithelial cells.METHODS: ARPE-19 cells cultured in vitro were irradiated by 405 nm blue light at 50 mW/cm2 irradiance with different duration and were divided into control, 16.3J/cm2, 32.6J/cm2, and 65.2J/cm2 groups; the 65.2J/cm2 group was defined as the high-level blue light irradiation group and cells were further divided into control, high-level blue light irradiation group and high-level blue light irradiation + ferroptosis inhibitor group. CCK-8 assay was used to detect cell viability, commercial kits were used to detect intracellular glutathione(GSH), ferrous iron and malondialdehyde(MDA)concentration, and Western blot was used to detect the relative expression of glutathione peroxidase 4(GPX4)and xCT proteins in cells.RESULTS: The decrease of ARPE-19 cell viability caused by blue light irradiation was dose-dependent, and the reduction of intracellular GSH concentration, the increase of ferrous iron concentration and MDA concentration were all caused by high-level blue light irradiation(all P&#x003C;0.05); the ferroptosis inhibitor partially restored cell viability and recovered intracellular GSH, reduced concentrations of MDA and ferrous iron in the blue light irradiation group(all P&#x003C;0.05). The relative expressions of GPX4 and xCT proteins were significantly decreased in the blue light irradiation group, and such change was alleviated by the ferroptosis inhibitor(P&#x003C;0.05).CONCLUSION: Blue light irradiation may induce ferroptosis in RPE cells by targeting the xCT and GPX4-associated antioxidant pathways.
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Objective?Diabetic retinopathy (DR), a microvascular complication of diabetes, is a leading cause of preventable blindness. Spectral domain optical coherence tomography (SD-OCT) provides cross-sectional and topographical imaging of the retina. SD-OCT resolves outer retinal layers into three hyperreflective bands—external limiting membrane (ELM), ellipsoid zone (EZ), and retinal pigment epithelium (RPE). In this article, we have studied the role of these outer retinal layers in structural and molecular changes taking place in DR. Materials and Methods?Articles with clinical features, pathogenesis, diagnosis, and treatment of DR were thoroughly studied. Articles were searched on PubMed, MEDLINE, and Cochrane Library from 2000 to 2020. Studies focusing on the role of ELM, EZ, and RPE in pathogenesis of DR based on SD-OCT were included. Results?The long-standing hyperglycemia leads to protein glycosylation resulting in formation of advanced glycation end products (AGEs). AGEs have an impact through their effect on retinal microvasculature, vascular endothelial growth factor (VEGF), intercellular adhesion molecule-1, nitrosative and oxidative stress, and vitamin D and calcium metabolism. All these factors have been linked with disruption of outer retinal layers. AGEs lead to vascular endothelial dysfunction and release of proangiogenic factors by increasing the expression of VEGF in retinal pericytes and RPE cells. This leads to leakage and fluid accumulation resulting in diabetic macular edema (DME). In DME, there is sequential disruption of ELM and EZ and decrease in visual acuity (VA). The RPE alterations have been reported to be associated with the severity of DR and decrease in VA. Anti-VEGF therapy, most common treatment of DME, leads to restoration of barrier effect of ELM, it was found to be restored first followed by EZ restoration. Newer anti-AGEs agents and their receptor blockers are being developed which have a positive effect on maintaining the health of RPE. Conclusion?A complex molecular association exists between the structural changes in ELM, EZ, and RPE in DR. SD-OCT is an indispensable tool to study these changes as integrity of these outer layers of retina is essential for maintaining visual function of retina in DR.
ABSTRACT
1. INTRODUCCIÓN El desprendimiento de retina es un problema visual grave que puede ocurrir a cualquier edad, aunque suele darse en individuos de edad media o en personas de la tercera edad. La incidencia es relativamente baja considerando que las estima-ciones varían según zonas geográficas; y, se han reportado datos de entre 6,3 y 17,9 por 100 000 habitantes. Otras características im-portantes a considerar son la degeneración en encaje de 45,75% y la miopía de 47,28% que influyen en la presentación del desprendi-miento de retina. Al mismo tiempo que la edad, los cambios vítreos retinianos y la presencia de pseudofaquia1,2. Además, de los factores oculares relacionados también influyen, el seguimiento inadecuado de los factores de riesgo y el difícil acceso a médicos especialistas que se traduce en retraso en el diagnóstico certero y tratamiento tardío que implica deterioro del pronóstico visual cuando el área macular está incluida en el área desprendida con pobres resultados en adultos jóvenes y en edad productiva.El tratamiento evitará el deterioro o pérdida irreversible de la visión. El pronóstico con tratamiento quirúrgico es bueno si el des-prendimiento no incluye a la mácula.
1. INTRODUCTIONRetinal Detachment is a serious visual problem that can occur at any age, although it usually occurs in middle-aged or elderly in-dividuals. The incidence is relatively low considering that estimates vary ac-cording to geographical areas; and, data have been reported be-tween 6,3 and 17,9 per 100 000 inhabitants. Other important cha-racteristics to consider are socket degeneration of 45,75% and myopia of 47,28% that influence the presentation of retinal deta-chment, as well as age, vitreoretinal changes and the presence of pseudophakia1,2.In addition to the related ocular factors, inadequate follow-up of risk factors and difficult access to medical specialists also play a role, resulting in delayed accurate diagnosis and late treatment that implies deterioration of the visual prognosis when the macular area is included in the detached area with poor results in young adults and those of productive age.Treatment will prevent irreversible deterioration or loss of vision. The prognosis with surgical treatment is good if the detachment does not include the macula.
Subject(s)
Humans , Male , Female , Retinal Detachment , Visual Acuity , Vitreoretinopathy, Proliferative , Vitreous Detachment , Retinal Pigment Epithelium , Fundus Oculi , Ophthalmology , Therapeutics , Blindness , Diabetic Retinopathy , Diagnostic Techniques, Ophthalmological , Ecuador , Vitreoretinal Surgery , MyopiaABSTRACT
ABSTRACT Combined hamartoma of the retina and retinal pigment epithelium is a rare, benign intraocular tumor. Hamartoma of the retina and retinal pigment epithelium has been described in the literature as a condition presenting with variable retinal damage, ranging from partial epiretinal involvement to complete distortion of the retinal layers and retinal pigment epithelium. We report the case of an 8-year-old girl presenting with longstanding strabismus who was diagnosed with Hamartoma of the retina and retinal pigment epithelium based on multimodal imaging assessment. We explored the particular imaging findings from studies using spectral-domain optical coherence tomography, fundus autofluorescence, optical coherence tomography angiography, and fluorescein angiography.
RESUMO O hamartoma combinado de retina e epitélio pigmentar da retina consiste em um tumor intraocular raro com comportamento benigno. O hamartoma combinado de retina e epitélio pigmentar da retina foi descrito na literatura apresentando dano retiniano variável, desde o envolvimento epirretiniano parcial até distorção completa das camadas retinianas e do epitélio pigmentar da retina. Relatamos o caso de uma menina de 8 anos com estrabismo de longa data que foi diagnosticada com hamartoma combinado de retina e epitélio pigmentar da retina, com base na avaliação de imagem multimodal. Exploramos os achados de imagem específicos de estudos usando tomografia de coerência óptica de domínio espectral, autofluorescência, angiografia por tomografia de coerência óptica e angiografia fluorescente.