Postnatal development of rat retina:a continuous observation and comparison between the organotypic retinal explant model and in vivo development

The organotypic retinal explant culture has been established for more than a decade and offers a range of unique advantages compared with in vivo experiments and cell cultures.However,the lack of systematic and continuous comparison between in vivo retinal development and the organotypic retinal explant culture makes this model controversial in postnatal retinal development studies.Thus,we aimed to verify the feasibility of using this model for postnatal retinal development studies by comparing it with the in vivo retina.In this study,we showed that postnatal retinal explants undergo normal development,and exhibit a consistent structure and timeline with retinas in vivo.Initially,we used SOX2 and PAX6 immunostaining to identify retinal progenitor cells.We then examined cell proliferation and migration by immunostaining with Ki-67 and doublecortin,respectively.Ki-67-and doublecortin-positive cells decreased in both in vivo and explants during postnatal retinogenesis,and exhibited a high degree of similarity in abundance and distribution between groups.Additionally,we used Ceh-10 homeodomain-containing homolog,glutamate-ammonia ligase(glutamine synthetase),neuronal nuclei,and ionized calcium-binding adapter molecule 1 immunostaining to examine the emergence of bipolar cells,Müller glia,mature neurons,and microglia,respectively.The timing and spatial patterns of the emergence of these cell types were remarkably consistent between in vivo and explant retinas.Our study showed that the organotypic retinal explant culture model had a high degree of consistency with the progression of in vivo early postnatal retina development.The findings confirm the accuracy and credibility of this model and support its use for long-term,systematic,and continuous observation.

Effect of Aβ protein on inhibiting proliferation and promoting apoptosis of retinal pigment epithelial cells

AIM： To identify the effect and regulatory mechanism of amyloid β （Aβ） protein on retinal pigment epithelial （RPE） cells in cell proliferation and apoptosis, and clarify Aβ role in the pathogenesis of age-related macular degeneration （AMD）. METHODS： The model of Aβ25-35 protein cytotoxicity in RPE cell was successfully established to investigate the effect of Aβ protein on RPE cells in vitro. Based on Aβ protein, the specific inhibitors （HY-50682 or BAY11-7082） or activating agent （lipopolysaccharide） was used to analyze the regulatory mechanism of Aβ protein to RPE cells on cell proliferation and apoptosis by flow cytometry, real-time polymerase chain reaction, Western blotting, enzyme-linked immunosorbent assay and dual-luciferase reporter gene assay. RESULTS： The number of RPE cells, treated with Aβ25-35 from 0.3 to 60 μmol/L, significantly reduce （P〈0.01）, and had the dose-dependent effect. Aβ protein 60 μmol/L inhibits the G1/S phase transition （P〈0.01） and down-regulated cyclin E mRNA level （P〈0.01）. Similarly, Aβ25-35 induced a significant increase of cell apoptosis, accompanied by the significantly higher level of activated caspase 3 protein. Furthermore, nuclear factor-kappaB （NF-κB） activity and hosphorylated Iκ-Ba level would significantly lower in treated RPE cells. Using specific inhibitors or activating agent based on the Aβ, the cell numbers, NF-κB activity, phosphorylated Iκ-Ba level, receptor for advanced glycation endproducts （RAGE） gene expression levels, cyclin E mRNA level and activated caspase 3 level had accordingly changed by different methods, confirming that RAGE/NF-κB signaling pathway involved in the regulation of Aβ protein on RPE cell apoptosis and proliferation. CONCLUSION： Aβ protein inhibits cell proliferation and activates apoptosis via inactivation of the RAGE/NF-κB signaling pathway in RPE cell.

PROPERTIES OF PROLIFERATION AND DIFFERENTIATION OF NEONATAL RAT RETINAL PROGENITOR CELLS IN VITRO

Objective To investigate the properties of proliferation and differentiation of neonatal rat retinal progenitor cells (RPCs) in vitro. Methods RPCs were isolated from neonatal SD rats neural retina and cultured in DMEM/F12+N2 with EGF and bFGF (suspension medium )or 10%FBS without EGF and bFGF (differentiation medium). The cells grew as suspended spheres or adherent monolayers, depending on different culture conditions. The neural stem cells or retinal progenitors, neurons, astrocytes, retinal ganglion cells, rod photoreceptors and the proliferating cells were evaluated with immunofluorescence analysis by Nestin or Pax6, Map2, GFAP, Thy-1, Rhodopsin and BrdU antibodies respectively. Results RPCs could propagate and differentiate in suspension or differentiation medium and express the markers of Nestin (92.86%) or Pax6 (86.75%), Map2 (38.54%), GFAP (20.93%), Thy-1 (27.66%) and Rhodopsin(13.33%)in suspension medium; however, Nestin (60.27%), Pax6 (52%), Map2 (34.94%), GFAP (38.17%), Thy-1(30.84%) and Rhodopsin (34.67%) in differentiation medium. 96.4% of the population in the neurospheres was BrdU-positive cells. The cells could spontaneously adherent forming some subspheres and retinal specific cell types. Conclusion Neonatal rat RPCs possess the high degree of proliferation and can differentiate into neurons, astrocytes, retinal ganglion cells and rod photoreceptors in vitro. There are different proportions for RPCs to differentiate into specific cell types.

Vitreous hemorrhage and fibrovascular proliferation after laser-induced chorioretinal venous anastomosis

·AIM:To describe a case in which vitrectomy was required for vitreous hemorrhage and fibrovascular proliferation after laser-induced chorioretinal venous anastomosis (LCVA) for non-ischemic central retinal vein occlusion (CRVO).·METHODS:Observational case report.·RESULTS:A 72-year-old man complained of central scotoma in the left eye,and was diagnosed as suffering from non-ischemic CRVO.LCVA was performed in another hospital.Although favorable visual function was briefly maintained postoperatively,severe vitreous hemorrhage developed in his left eye,necessitating vitrectomy.·CONCLUSION:Considering that LCVA carries a risk of serious complications,we must apply this treatment with caution,especially in ethnic groups,such as the Japanese,in whom pigmentation reacts to photocoagulation excessively.·

Clinical and experimental study on angiopoietin-like protein 8 associated with proliferative diabetic retinopathy

AIM：To confirm the role of angiopoietin-like protein 8（Angptl 8） in proliferative diabetic retinopathy（PDR）.METHODS：The sera and aqueous humor of 10 PDR patients and 10 non-diabetic retinopathy（NDR） patients（idiopathic macular hole patients） were collected and the expression of Angptl 8 was detected by enzyme linked immune-sorbent assay（ELISA）.Experimental diabetes mice model was induced with streptozotocin.The expression of glycosylated hemoglobin and Angptl 8 in sera was detected.Recombinant Angptl 8 was re-infused into wild type（WT） diabetic mice and spatial frequency threshold and contrast sensitivity were measured.In vitro retinal pigment epithelium（RPE） were stimulated by recombinant Angptl 8 for 24 h.MMT assay were used to detect cell proliferation.At the same time,q RT-PCR and Western blot was used to measure the expression of proliferation-related factors in PRE cells.RESULTS：The expression of Angptl 8 was markedly increased in the sera and aqueous humor of PDR patients（F=99.02,P〈0.0001 in sera;t=10.42,P〈0.0001 in aqueous）.After successfully establishing the diabetic mice model,we found that glycosylated hemoglobin and Angptl 8 expression levels were increased.Re-infusion of recombinant Angptl 8 into WT diabetic mice could further decrease spatial frequency threshold and contrast sensitivity（P〈0.01）.In vitro,RPE cells stimulated by recombinant Angptl 8could increase the relative absorbance of MMT assay（1.486±0.042 vs 1.000±0.104,P〈0.05） and proliferating cell nuclear antigen（PCNA） expression（0.55±0.01 vs 0.29±0.03,P〈0.05）.The proliferative effect of Angptl 8 is mainly mediated by increasing the expression of proliferation-activating factors cyclin A1（4.973±0.205 vs 2.720±0.197,P〈0.05）,cyclin F（5.690±0.219 vs 4.297±0.292,P〈0.05） and E2 F2（2.297±0.102 vs 1.750±0.146,P〈0.05）,and reducing the expression of proliferation-inhibiting factors cdkn1（2.370±0.074 vs 3.317±0.135,P〈0.05） and cdkn2（4.793±0.065 vs 5.387±0.149,P〈0.05）.CONCLUSION：The expression of Angptl 8 is increased in PDR,and the increased Angptl 8 can promote proliferation and increase proliferation-related factors.

Effects of resveratrol on ARPE-19 cell proliferation and migration via regulating the expression of proliferating cell nuclear antigen, P21,P27 and p38MAPK/MMP-9

AIM： To explore whether resveratrol （Res） can inhibit human retinal pigment epithelial cell （ARPE-19 cell） proliferation and migration, and to research the molecular mechanisms.METHODS： ARPE-19 cells were pretreated with various concentrations at 0, 50, 100, 150, 200 and 300 μmol/L of Res, and with 0 μmol/L Res as the control for 24, 48 and 72h. The cell proliferation, apoptosis and migration were measured with cell counting kit-8 （CCK-8）, flow cytometry, and wound-healing and Transwell assays, respectively. The expression of proliferating cell nuclear antigen （PCNA）, P21 and P27, as well as matrix metalloproteinase-9 （MMP-9） and p38 mitogen-activated protein kinases （p38MAPK） was identified by Western blot.RESULTS： Cell proliferation was effectively inhibited by Res （P〈0.05）. When pretreated with Res, cells arrested in S-phase increased remarkably （P〈0.05）, but the apoptosis ratios showed no significant difference between the treatment and control groups （P〉0.05）. Cell migration was suppressed by Res both in wound-healing assay and Transwell migration assay （P〈0.05）. Decreases of PCNA, MMP-9 and p38MAPK, as well as increases of P21 and P27 were detected by Western blot （P〈0.05）. CONCLUSION： Res can inhibit APRE-19 cell proliferation and migration in a concentration-dependent manner with up-regulation of the expression of P21 and P27, and down-regulation of PCNA, MMP-9 and p38MAPK.

Inhibition of PCNA Antisense Oligonucleotides Mediated by Liposome on mRNA Expression and Proliferation of h-RPE Cells

Summary： The proliferating cell nuclear antigen （PCNA） gene expression was blocked and retinal pigment epithelium （RPE） proliferation was inhibited by using antisense oligonucleotides （AS-ODN） mediated by liposome, to find a new genetic therapy of proliferative vitreoretinopathy （PVR）. RPE cells cultured in vitro were transfected with synthetic fluorescence labled AS-ODN mediated by liposome-Lipofectamine, and the intracellular distribution and persistence time of AS-ODN were dynamically observed. AS-ODN （0.07, 0.28 and 1.12 μ mol/L and sense oligonucleotides （S-ODN with the same concentrations as AS-ODN） mediated by liposome were delivered to the RPE cells cultured in vitro, and CPM values were measured by ^3H-TdR incorporation assay and analyzed statistically by variance by comparison with blank control group. Expression ofPCNA mRNA in RPE cells was detected by in situ hybridization after the treatment of different concentrations of PCNA AS-ODN and S-ODN, and the average optic density （AOD） was measured by image analysis system and was subjected to q-test and correlation analysis with CPM. Our results showed that AS-ODN mediated by liposome could quickly aggregate in cellular plasma and nuclei in 30 min and 6 h, and stayed for as long as 6 days. AS-ODN （0.28 and 1.12 μmol/L） markedly suppressed proliferation of RPE cells in a dose-dependent manner with the difference being statistically significant （P〈0.05 and P〈0.01, repectively） as compared with blank control group. AOD was well correlated with CPM （r=0.975）. It is concluded that liposome could increase transfection efficiency of AS-ODN in RPE cells, and AS-ODN could sequence-specifically suppress PCNA mRNA expression and proliferation of human RPE cells.

Retinal regeneration requires dynamic Notch signaling

Retinal damage in the adult zebrafish induces Müller glia reprogramming to produce neuronal progenitor cells that proliferate and differentiate into retinal neurons.Notch signaling,which is a fundamental mechanism known to drive cell-cell communication,is required to maintain Müller glia in a quiescent state in the undamaged retina,and repression of Notch signaling is necessary for Müller glia to reenter the cell cycle.The dynamic regulation of Notch signaling following retinal damage also directs proliferation and neurogenesis of the Müller glia-derived progenitor cells in a robust regeneration response.In contrast,mammalian Müller glia respond to retinal damage by entering a prolonged gliotic state that leads to additional neuronal death and permanent vision loss.Understanding the dynamic regulation of Notch signaling in the zebrafish retina may aid efforts to stimulate Müller glia reprogramming for regeneration of the diseased human retina.Recent findings identified DeltaB and Notch3 as the ligand-receptor pair that serves as the principal regulators of zebrafish Müller glia quiescence.In addition,multi-omics datasets and functional studies indicate that additional Notch receptors,ligands,and target genes regulate cell proliferation and neurogenesis during the regeneration time course.Still,our understanding of Notch signaling during retinal regeneration is limited.To fully appreciate the complex regulation of Notch signaling that is required for successful retinal regeneration,investigation of additional aspects of the pathway,such as post-translational modification of the receptors,ligand endocytosis,and interactions with other fundamental pathways is needed.Here we review various modes of Notch signaling regulation in the context of the vertebrate retina to put recent research in perspective and to identify open areas of inquiry.

Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters

Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon （660 nm） laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the ifrst week with a short period of treatment time （5 minutes） in which 65–66% of retinal ganglion cells survived the optic nerve axotomy whereas 45–47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These ifndings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal gan-glion cells.

Chordin-like 2 influences the differentiation fate of retinal pigment epithelium cells by dynamically regulating BMP pathway

AIM:To explore the functions of Chordin-like 2,which is encoded by CHRDL2,in the process of retinal pigmented epithelium(RPE)differentiation and damage repair.METHODS:The fetal RPE cells(f RPE)was obtained from aborted fetus which obeyed medical ethics.Real-time quantitative polymerase chain reaction was used to measure expression quantity of CHRDL2 and other functional genes expression.Knocking down and overexpression was used to analyze the functions about Chordin-like 2.Enzyme-linked immunosorbent assay(ELISA)was used to detect the secretion of bone morphogenetic proteins 4(BMP4).Flow cytometry was used to analyze cell cycle.Cell morphology was observed by phase contrast microscope(PCM).RESULTS:In normal RPE cells,CHRDL2 was firstly upregulated and followed a downregulation but eventually,it was expressed higher than the cells which undergone epithelial-mesenchymal transition(EMT).After knocking down CHRDL2,the secretion of BMP4 was decreased,RPErelated genes(OTX2,MITF,RPE65)were downregulated while EMT-related genes(SNAI1,VIM)were upregulated.However,the expression of these related genes after overexpression of CHRDL2 had contrary results.Chordin-like 2 also regulated the cell cycle by regulating BMP pathway.When CHRDL2 was knocked down,more f RPE cells stayed in S phase of cell cycle,while adding BMP4 reduced the proportion of the cells in S phase.However,overexpression of CHRDL2 increased more BMP4 secretion,this effect decreased the number of cells in S phase,but exogenous BMP inhibitor also could change this effect.At last,in the process of RPE cells differentiation,adding BMP4 at early stage could intervene normal RPE differentiation.Compared with BMP4,inhibiting BMP pathway had no significant negative effect at early stage,but suppressed differentiation at late stage.CONCLUSION:BMP pathway can be activated in a correct temporal order,otherwise,the cells have incorrect differentiation orientation.And Chordin-like 2 plays a role in dynamic regulation of BMP pathway and it also regulates the differentiation of RPE cells.Therefore,this research enlightens a new direction to inhibit EMT and promote cell redifferentiation after injury.

Small interfering RNA targeting PGC-1α inhibits VEGF expression and tube formation in human retinal vascular endothelial cells

AIMTo determine whether small interfering RNA (siRNA) of PGC-1α could inhibit vascular endothelial growth factor (VEGF) expression and tube formation in human retinal vascular endothelial cells (hRVECs).METHODShRVECs transfected with peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) siRNA were incubated for 24h and then placed into a normoxic (20%, O2) or hypoxic (1%, O2) environment for another 16h. PGC-1α mRNA and protein levels were detected by real-time PCR and Western blot. VEGF mRNA and protein levels were detected by real-time PCR and ELISA. Cell proliferation was evaluated by BrdU incorporation assay. Forty-eight hours after siRNA transfection, hRVECs were planted into Matrigel-coated plates and cultured under normoxic (20%, O2) or hypoxic (1%, O2) conditions for another 48h. The tube formation of hRVECs was observed under an optical microscope and quantified by counting the number of branch points and calculating the total tube length.RESULTSPGC-1α mRNA and protein levels were significantly reduced by PGC-1α siRNA, and VEGF mRNA and protein levels also decreased significantly. The percentage of BrdU-labeled cells in siPGC-1α groups were significantly decreased compared with control siRNA groups under normoxia and hypoxia in cell proliferation assay. In the tube formation assay, PGC-1α siRNA treated cells formed significantly fewer tubes.CONCLUSIONBlocking PGC-1α expression can inhibit VEGF expression in hRVECs and inhibit their ability to form tubes under both normoxic and hypoxic conditions.

糖尿病氧化应激环境中α-Klotho对巨噬细胞-血管内皮细胞串扰的影响

目的:探讨糖尿病氧化应激环境中过表达α-Klotho(KL)的小鼠单核巨噬细胞白血病细胞(RAW264.7)对人脐静脉内皮细胞(HUVECs)增生、迁移、管腔形成以及紧密连接的影响。方法:将RAW264.7细胞分为对照组、4-羟壬二酸酯(4HNE)组、4HNE+KL组,采用免疫荧光实验检测RAW264.7细胞F4/80的表达。制备3组细胞的条件培养基用于培养HUVECs,分为M-NC组、M-4HNE组和M-4HNE+KL组。采用CCK8实验检测血管内皮细胞增生,采用划痕实验和Transwell实验检测迁移,采用管腔形成实验检测管腔形成,采用Western blot实验检测闭合蛋白5(Claudin 5)、咬合蛋白(Occludin)、带状闭合蛋白1(ZO 1)表达水平。结果:免疫荧光实验结果显示,4HNE组RAW264.7细胞F4/80荧光强度较对照组明显增强,而4HNE+KL组F4/80荧光强度较4HNE组明显减弱(均P<0.05)。CCK8实验结果显示,相比于M-NC组,M-4HNE组HUVECs增生显著增加,而M-4HNE+KL组HUVECs增生较M-4HNE组显著下降(均P<0.01)。划痕实验和Transwell实验结果显示,相比于M-NC组,M-4HNE组HUVECs迁移显著增强,而M-4HNE+KL组HUVECs迁移较M-4HNE组显著减弱(均P<0.01)。管腔形成实验结果显示,相比于M-NC组,M-4HNE组HUVECs管腔数显著增加,而M-4HNE+KL组管腔数较M-4HNE组显著下降(均P<0.01)。Western blot实验结果显示,相比于M-NC组,M-4HNE组HUVECs中Claudin 5、Occludin、ZO 1蛋白的相对表达量明显减少,而M-4HNE+KL组Claudin 5、Occludin、ZO 1蛋白的相对表达量较M-4HNE组明显增加(均P<0.01)。结论:KL通过改变糖尿病氧化应激环境中巨噬细胞激活状态抑制了HUVECs的增生、迁移、管腔形成,并增强了HUVECs的紧密连接。

玄参提取物对糖尿病视网膜病变微血管内皮细胞损伤的影响及其作用机制

目的:探讨玄参提取物抑制微小RNA-646(miR-646)改善微血管内皮细胞损伤缓解糖尿病视网膜水肿的影响及其作用机制。方法:根据简单随机化法将人视网膜微血管内皮细胞(HRMEC)细胞分为对照组、模型组(30 mmol/L葡萄糖)、观察组(30 mmol/L葡萄糖+100μg/mL玄参提取物组)、模型+Anti-NC(转染Anti-NC+30 mmol/L葡萄糖)、模型+Anti-miR-646(转染Anti-miR-646+30 mmol/L葡萄糖)组;将30只小鼠根据简单随机化法分为对照组、模型组(60 mg/kg的链脲佐菌素)、观察组(60 mg/kg的链脲佐菌素+100 mg/kg-的玄参提取物),每组10只。比较各组细胞增殖,迁移及miR-646、血管内皮生长因子A(VEGFA)、细胞间黏附分子-1(ICAM-1)、血小板-内皮细胞黏附分子(CD31)表达;比较各组小鼠视网膜组织ICAM-1、CD31表达及视网膜组织水肿情况。结果:细胞实验结果显示,与对照组比较,模型组细胞miR-646、ICAM-1表达显著升高,VEGFA、CD31表达显著下降(均P<0.05);与模型组比较,观察组细胞miR-646、ICAM-1表达显著降低,VEGFA、CD31表达显著升高(均P<0.05);与模型+Anti-NC组比较,模型+Anti-miR-646组细胞增殖率、迁移细胞数及VEGFA表达显著增加,miR-646表达及凋亡率显著降低(均P<0.05)。动物实验结果显示,与对照组比较,模型组小鼠视网膜组织中miR-646、ICAM-1表达显著升高,VEGFA、CD31表达显著下降(均P<0.05),同时小鼠视网膜组织水肿情况加重;与模型组比较,观察组小鼠网膜组织中miR-646、ICAM-1表达显著降低,VEGFA、CD31表达显著升高(均P<0.05),同时小鼠视网膜组织水肿明显得到缓解。结论:玄参提取物可能通过miR-646/VEGFA机制调节HRMEC细胞增殖、迁移和凋亡,改善缓解糖尿病视网膜水肿。

P2X7/P2X4 Receptors Mediate Proliferation and Migration of Retinal Microglia in Experimental Glaucoma in Mice

Microglia are involved in the inflammatory response and retinal ganglion cell damage in glaucoma.Here,we investigated how microglia proliferate and migrate in a mouse model of chronic ocular hypertension(COH).In COH retinas,the microglial proliferation that occurred was inhibited by the P2X7 receptor(P2X7R)blocker BBG or P2X7R knockout,but not by the P2X4R blocker 5-BDBD.Treatment of primary cultured microglia with BzATP,a P2X7R agonist,mimicked the effects of cell proliferation and migration in COH retinas through the intracellular MEK/ERK signaling pathway.Transwell migration assays showed that the P2X4R agonist CTP induced microglial migration,which was completely blocked by 5-BDBD.In vivo and in vitro experiments demonstrated that ATP,released from activated Müller cells through connexin43 hemichannels,acted on P2X7R to induce microglial proliferation,and acted on P2X4R/P2X7R(mainly P2X4R)to induce microglial migration.Our results suggest that inhibiting the interaction of Müller cells and microglia may attenuate microglial proliferation and migration in glaucoma.

姜黄素对人视网膜色素上皮细胞增殖和VEGF表达的影响

目的探讨姜黄素对人视网膜色素上皮(hRPE)细胞增殖和血管内皮生长因子(VEGF)表达的影响。方法(1)采用不同浓度(5μg/mL、10μg/mL、20μg/mL、40μg/mL)的姜黄素干预hRPE细胞1 d、2 d、3 d、4 d、5 d、6 d,同时设置空白对照组(不给予姜黄素干预)。采用CCK-8法检测各时间点不同浓度姜黄素对hRPE细胞增殖的影响,采用流式细胞仪检测各时间点各组细胞周期时相分布情况。(2)将hRPE细胞分为姜黄素组和对照组,姜黄素组加入10μg/mL的姜黄素,对照组加入等体积培养液,采用实时荧光半定量PCR检测各组hRPE细胞VEGF mRNA的表达水平。结果(1)各浓度姜黄素对hRPE细胞均有抑制作用(均P<0.05),且随着药物浓度的增大、作用时间的延长,其抑制率呈升高趋势,整体呈现剂量和时间依赖性。(2)不同浓度姜黄素干预后,G_(0)/G_(1)期细胞比例均大于空白对照组,S期细胞比例和G_(2)/M期细胞比例均小于空白对照组(均P<0.05)。(3)姜黄素组hRPE细胞VEGF mRNA表达水平低于对照组(P<0.05)。结论姜黄素可以将hRPE细胞周期阻滞于S期从而抑制hRPE细胞的增殖,还可以降低hRPE细胞的VEGF表达水平。

miR-1-3p调控ANXA2表达对高糖诱导的视网膜微血管内皮细胞新生血管生成的影响

目的 探讨微小RNA-1-3p(miR-1-3p)/膜联蛋白A2(ANXA2)分子轴在高糖诱导的人视网膜微血管内皮细胞(HRMECs)新生血管生成过程中的作用机制。方法 体外培养HRMECs并采用高糖(HG)处理细胞建立细胞损伤模型。HRMECs分组处理:Con组(含体积分数10%胎牛血清的DMEM培养)、HG组(25 mmol·L^(-1)D-葡萄糖培养)、HG+miR-NC组(转染miR-NC)、HG+miR-1-3p组(转染miR-1-3p mimics)、HG+sh-NC组(转染sh-NC)、HG+sh-ANXA2组(转染sh-ANXA2)、HG+miR-1-3p+pcDNA组(转染miR-1-3p mimics+pcDNA)、HG+miR-1-3p+pcDNA-ANXA2组(转染miR-1-3p mimics+pcDNA-ANXA2)。转染48 h后收集细胞,采用25 mmol·L^(-1)的D-葡萄糖培养基培养HRMECs 24 h。采用MTT、Transwell小室实验分别检测细胞活力、迁移细胞数。管腔形成实验检测管腔形成数。双荧光素酶报告实验检测miR-1-3p与ANXA2的靶向关系。Western blot检测VEGF、MMP-2蛋白水平。结果 与Con组比较,HG组miR-1-3p表达水平降低,ANXA2 mRNA及蛋白水平均升高,差异均有统计学意义(均为P<0.05)。与Con组比较,HG组细胞活力升高,迁移细胞数、管腔形成数增多,VEGF、MMP-2蛋白水平升高,差异均有统计学意义(均为P<0.05)。与HG+miR-NC组比较,HG+miR-1-3p组细胞活力降低,迁移细胞数、管腔形成数减少,VEGF、MMP-2蛋白水平降低,差异均有统计学意义(均为P<0.05)。与HG+sh-NC组比较,HG+sh-ANXA2组细胞活力降低,迁移细胞数、管腔形成数减少,VEGF、MMP-2蛋白水平降低,差异均有统计学意义(均为P<0.05)。与HG+miR-1-3p+pcDNA组比较,HG+miR-1-3p+pcDNA-ANXA2组细胞活力升高,迁移细胞数、管腔形成数增多,VEGF、MMP-2蛋白水平升高,差异均有统计学意义(均为P<0.05)。结论 miR-1-3p过表达可通过靶向调控ANXA2表达抑制HRMECs的增殖、迁移及新生血管生成。

二甲双胍对高糖诱导的RF/6A细胞增殖、迁移和血管形成的影响及其可能机制

目的研究二甲双胍(MET)对高糖诱导的恒河猴脉络膜⁃视网膜内皮细胞RF/6A增殖、迁移和血管形成的影响,并初步探讨其作用机制。方法RF/6A细胞随机分为5组:NC组、HG组、HG+15 mmol·L^(-1) MET组、HG+30 mmol·L^(-1) MET组、HG+45 mmol·L^(-1) MET组,CCK⁃8法检测细胞增殖情况。将RF/6A细胞随机分为4组:NC组和NC+15 mmol·L^(-1) MET组、NC+30 mmol·L^(-1) MET组、NC+45 mmol·L^(-1) MET组,CCK⁃8法检测MET的细胞毒性。将RF/6A细胞随机分为3组:NC组、HG组和HG+15 mmol·L^(-1) MET组,细胞划痕法和Transwell法检测细胞迁移,Matrigengel法检测细胞血管形成,RT⁃PCR、Western blot检测Hippo信号通路的核心成分YAP、TEAD1的mRNA及蛋白表达。结果CCK⁃8法检测结果显示,与NC组比较,HG组RF/6A细胞的增殖活性升高(P<0.001);与HG组比较,HG+15 mmol·L^(-1) MET组、HG+30 mmol·L^(-1) MET组和HG+45 mmol·L^(-1) MET组RF/6A细胞的增殖活性均降低(均为P<0.001)。与NC组比较,NC+15 mmol·L^(-1) MET组RF/6A细胞增殖活性无变化(P=0.2273),因此选择15 mmol·L^(-1) MET进行后续实验。细胞划痕法和Transwell法检测结果显示,与NC组比较,HG组RF/6A细胞的迁移率升高、迁移个数增加(均为P<0.01);与HG组比较,HG+15 mmol·L^(-1) MET组RF/6A细胞的迁移率降低、迁移个数减少(均为P<0.01)。Matrigengel法检测结果显示,与NC组比较,HG组RF/6A细胞的血管相对总长度增加(P<0.05);与HG组比较,HG+15 mmol·L^(-1) MET组RF/6A细胞的血管相对总长度减少(P<0.01)。RT⁃PCR检测结果显示,与NC组比较,HG组RF/6A细胞的YAP和TEAD1 mRNA相对表达量均增加(均为P<0.05);与HG组比较,HG+15 mmol·L^(-1) MET组RF/6A细胞的YAP和TEAD1 mRNA相对表达量均减少(均为P<0.05)。Western blot检测结果显示,与NC组比较,HG组RF/6A细胞的YAP和TEAD1蛋白相对表达量均增加(均为P<0.05);与HG组比较,HG+15 mmol·L^(-1) MET组RF/6A细胞的YAP和TEAD1蛋白相对表达量均减少(均为P<0.05)。结论MET可抑制高糖诱导的RF/6A细胞增殖、迁移和血管形成,下调YAP、TEAD1的mRNA及蛋白表达,推测其作用机制与Hippo信号通路有关。

LncRNA NEAT1调节微小RNA-144-3p/NOVA1轴对高糖诱导的人视网膜微血管内皮细胞损伤的影响

目的探究长链非编码RNA(long non-coding RNA,LncRNA)核富含丰富的转录本1(nuclear-enriched abundant transcript 1,NEAT1)通过微小RNA(micro RNA,miR)-144-3p/神经肿瘤腹侧抗原1(neural tumor ventral antigen 1,NOVA1)对高糖诱导的人视网膜微血管内皮细胞(human retinal microvascular endothelial cells,hRMECs)损伤的影响。方法将h RMECs分为高糖组(不转染)、对照组(不转染)、高糖+si-NEAT1-阴性对照(negative control,NC)组(转染siRNA-NC)、高糖+si-NEAT1组(转染NEAT1 siRNA)、高糖+si-NEAT1+抑制剂-NC组(共转染NEAT1 siRNA+抑制剂-NC)、高糖+si-NEAT1+miR-144-3p抑制剂组(共转染NEAT1 siRNA+miR-144-3p抑制剂)、高糖+si-NOVA1-NC组(转染NOVA1 siRNA-NC)、高糖+si-NOVA1组(转染NOVA1 siRNA)。实时荧光定量聚合酶链反应技术(real-time fluorescent quantitative polymerase chain reaction,qRT-PCR)检测hRMECs中NEAT1、miR-144-3p表达量;CCK-8、Transwell和血管形成实验分别分析hRMECs增殖、迁移和血管形成能力;双荧光素酶报告实验分析NEAT1与miR-144-3p、miR-144-3p与NOVA1的结合情况;Western blot检测NOVA1、VEGF蛋白表达。结果与对照组比较,高糖组hRMECs中NEAT1表达(2.67±0.13 vs.1.02±0.08)、相对活力、迁移数量[(271.50±20.35)个vs.(144.30±16.41)个]、成管节点数[(426.50±22.75)个vs.(181.70±12.43)个]、管长度[(12725.46±136.57)μm vs.(8009.32±107.32)μm]均较高,miR-144-3p表达(0.46±0.06 vs.1.00±0.05)较低,差异有统计学意义(P<0.05)。敲低NEAT1可明显下调h RMECs中NEAT1的表达,上调miR-144-3p的表达,同时降低NOVA1(0.80±0.09 vs.1.35±0.07)、血管内皮生长因子(vascular endothelial growth factor,VEGF)蛋白表达及hRMECs的相对活力、迁移数量[(231.60±14.25)个vs.(271.50±20.35)个]、成管节点数[(234.30±13.18)个vs.(426.50±22.75)个]和管长度[(9208.74±130.85)μm vs.(12725.46±136.57)μm],差异有统计学意义(P<0.05),上述作用可被miR-144-3p抑制剂减弱。NEAT1可结合并下调miR-144-3p表达,且NOVA1为miR-144-3p的靶基因。敲低NOVA1可明显降低hRMECs相对活力、迁移数量、成管节点数、管长度,差异有统计学意义(P<0.05)。结论敲低NEAT1可上调miR-144-3p表达,下调NOVA1蛋白表达,进而抑制hRMECs增殖、迁移和血管形成能力。

益阴明目汤调节TRAAK表达对缺氧视网膜神经节细胞增殖和凋亡的影响

目的:探讨益阴明目汤对缺氧视网膜神经节细胞RGC5增殖和凋亡的作用及其机制。方法:将RGC5细胞分为对照组、缺氧组、益阴明目汤低剂量组、益阴明目汤中剂量组和益阴明目汤高剂量组。益阴明目汤低、中、高剂量组分别用10μmol/L、20μmol/L、40μmol/L益阴明目汤处理4 h后在低氧条件下培养24 h。缺氧组仅予以缺氧处理24 h。分别将si-con、si-TRAAK转染RGC5细胞,10 h后缺氧处理24 h。CCK8法检测细胞增殖,western blotting检测细胞周期蛋白D1(CyclinD1)、Ki-67、Cleaved Caspase-3、Bax、Bcl-2和TRAAK蛋白表达,TUNEL法检测细胞凋亡,RT-qPCR检测TRAAK基因表达。结果:与对照组相比,缺氧组细胞增殖率和TRAAK、CyclinD1、Ki-67、Bcl-2蛋白表达水平降低,细胞凋亡率和Cleaved Caspase-3、Bax蛋白表达水平升高(均P<0.05)。与缺氧组比较,益阴明目汤中、高剂量组细胞增殖率和TRAAK、CyclinD1、Ki-67、Bcl-2表达水平升高,细胞凋亡率和Cleaved Caspase-3、Bax蛋白表达水平降低(均P<0.05)。沉默TRAAK表达可逆转益阴明目汤对缺氧RGC5细胞的上述作用(均P<0.05)。结论:益阴明目汤可能通过上调TRAAK表达来促进缺氧诱导的视网膜神经节细胞增殖,并抑制细胞凋亡。

RCS大鼠自然病程中视网膜边缘生发区细胞增殖及Shh／Ptc信号途径改变的观察

目的观察遗传性视网膜色素变性RCS大鼠病程发展中视网膜边缘生发区Shh/Ptc信号途径改变及其与该区细胞增殖能力变化的关系。方法RCS大鼠按出生后病程变化分为15、30、60、90 d 4组(免疫组化每组4只,PCR每组3只),以同龄含色素的正常大鼠(Long-Evan’s大鼠)作为正常对照。视网膜组织切片DAPI荧光染色观察外核层(outernuclear layer,ONL)厚度的变化;视网膜细胞增殖标记Ki67免疫荧光染色观察视网膜边缘生发区细胞增殖能力的变化;荧光定量PCR检测视网膜边缘生发区Shh/Ptc信号途径中关键分子Shh、Ptc1、Smo和Gli1 mRNA表达水平。结果①RCS大鼠从第15天开始,随着年龄的增加视网膜ONL逐渐变薄,第90天ONL几乎消失。②正常对照组大鼠视网膜边缘生发区Ki67阳性细胞较少,与同龄正常对照组大鼠相比,出生30、60 d组大鼠Ki67阳性细胞数均显著增多(P<0.05);大鼠各年龄组间比较,60 d组Ki67阳性细胞数明显增多(P<0.01)。③60 d组大鼠视网膜边缘生发区Shh、Ptc1、Smo和Gli1mRNA表达水平明显上调。结论出生后60 d RCS大鼠视网膜边缘生发区Shh/Ptc信号途径的激活,可能刺激了该部位细胞短期的增殖。