内皮抑素基因转移抑制视网膜新生血管的实验研究

目的评价脂质体介导的内皮抑素(ES)基因转移抑制缺氧诱导的小鼠视网膜新生血管的效果。探讨基因转移抑制视网膜新生血管的可行性。方法制备阳离子脂质体及PCDNA3ES复合物。选1周龄C57Bl/6N小鼠置于氧浓度为(75±2)%的氧箱中5d。回到正常环境中诱导视网膜新生血管模型。在小鼠离开氧箱的当日,向ES注射组鼠玻璃体腔注射2μl脂质体PCDNA3ES复合物;载体对照组注射等量脂质体空白载体复合物;空白对照组小鼠注射等量PBS。采用ES抗体免疫组化方法检测ES蛋白在视网膜的表达;回到正常环境中后5d,采用荧光标记的右旋糖酐血管灌注下视网膜铺片方法观察视网膜新生血管的分布;组织学切片观察比较突破视网膜内界膜的血管内皮细胞数量;透射电镜观察ES转移对视网膜超微结构的影响。结果免疫组化检查发现ES注射组小鼠玻璃体腔注射ES后24h开始有ES表达,主要位于视网膜神经纤维层细胞中,维持至少2周仍见表达;视网膜铺片观察可见空白对照组在无灌注区边缘均可见新生血管芽及荧光渗漏。ES注射组见新生血管芽明显减少;组织学检查ES注射组较其他两组突破视网膜内界膜的细胞数量减少,差异有统计学意义;ES转移后电镜下视网膜各层超微结构未见明显改变。结论采用玻璃体腔注射方法行脂质体介导的内皮抑素基因转移可以一定程度抑制缺氧诱导的小鼠视网膜新生血管生长,对视网膜无明显的毒副作用。应进一步优化转移条件以提高治疗效果。     

慢病毒介导sFlt-1基因转移抑制视网膜新生血管的实验研究

目的研究可溶性fms样酪氨酸激酶-1（sFlt-1）对小鼠视网膜新生血管的抑制作用。方法将54只C57/6J小鼠随机分为3组,每组18只。将其中2组小鼠于生后第7天开始置于体积分数75%氧环境中,5d后返回正常空气环境中以建立氧诱导的小鼠视网膜新生血管模型,于17d时玻璃体腔内分别注射1μLlenti-GFP和携带sFlt-1基因片段的重组慢病毒,设为模型对照组和lenti.sFlt-1组,18只正常空气环境中生长的小鼠玻璃体腔内注射1μL磷酸盐缓冲液,设为正常对照组。通过小鼠眼球连续切片苏木精-伊红染色和心脏荧光素灌注视网膜铺片法观察小鼠视网膜新生血管的变化情况,采用免疫组织化学染色法检测视网膜血管内皮生长因子（VEGF）和VEGF受体-2（KDR/Flk-1）的表达变化。结果经RT-PCR扩增的靶基因片段序列与GenBank中的标准序列相吻合。感染后的人RPE细胞能够表达sFlt-1蛋白。正常对照组小鼠视网膜内界膜平整,模型对照组小鼠突破内界膜血管内皮细胞核的数目为（47.26±6.76）,而lenti.sFlt-1组为（5.21±1.93）个,差异有统计学意义（P〈0.05）。视网膜铺片可见新生血管荧光素渗漏表现。慢病毒携带的sFlt-1基因片段转移至模型小鼠视网膜后,发现突入玻璃体腔的血管内皮细胞核数较模型对照组显著减少,并且视网膜毛细血管扩张、微血管瘤样改变、新生血管等荧光素渗漏表现亦明显减少;同时lenti.sFlt-1组VEGF的表达与模型对照组相比在视网膜神经节细胞层和内核层仍呈现强阳性染色,无明显变化,而KDR/Flk-1的阳性染色显著减少。结论慢病毒介导sFlt-1基因转移能显著抑制小鼠视网膜新生血管的发生。     

血管内皮细胞生长抑制因子VEGI151重组腺病毒对角膜新生血管的抑制作用

目的研究以复制缺陷型重组腺病毒为载体的血管内皮细胞生长抑制因子VEGI151对角膜新生血管的抑制作用。方法利用腺病毒载体pCA13构建携带VEGI151基因的质粒,经293A细胞包装、扩增,WesternBlot检测病变细胞内基因的蛋白质表达,体外检测AdVEGI151对ECV304细胞的抑制作用,缝线诱导法建立炎症性兔角膜新生血管模型,给予体内基因治疗。结果VEGI151重组腺病毒在病变细胞内能成功表达相对分子质量为17300的蛋白,体外实验表明,可以强烈抑制静脉内皮细胞的生长,体内实验表明,重组腺病毒对炎症性角膜新生血管的生长具有抑制作用。结论以复制缺陷型重组腺病毒为载体的血管内皮细胞抑制因子VEGI151基因治疗角膜新生血管效果显著,为角膜新生血管的基因治疗提供了新的思路。     

VEGF siRNA抑制鼠视网膜新生血管的实验研究

背景血管内皮生长因子（VEGF）在视网膜新生血管的发生过程中发挥重要作用,抑制VEGF是目前视网膜新生血管治疗和预防研究的热点。VEGF小片段干扰RNA（VEGFsiRNA）在抗肿瘤新生血管的研究中已经取得了显著疗效,但对于视网膜新生血管的干预作用报道较少。目的研究VEGF siRNA对鼠视网膜新生血管的抑制作用。方法48只新生C57BL／6J幼鼠采用随机数字表法随机分为正常对照组、模型对照组、空载体组和VEGF siRNA质粒转染组,每组12只幼鼠。7日龄C57BL／6J幼鼠36只及其母鼠置于密闭的氧舱5d建立缺氧性新生血管模型,其中12只幼鼠不进行质粒转染作为模型对照组,其余24只鼠玻璃体腔内注射脂质体（LF2000）包裹的空载体质粒或VEGF siRNA表达质粒。待小鼠19日龄时获取小鼠眼球并分离视网膜,用苏木精一伊红染色法计数各组小鼠视网膜新生血管内皮细胞核的数目,用实时荧光定量聚合酶链反应（tea-time PCR）法检测视网膜中VEGF mRNA的表达,并应用免疫荧光技术检测小鼠视网膜中VEGF蛋白的表达。结果正常对照组、模型对照组、空载体组和VEGFsiRNA质粒转染组19日龄小鼠视网膜突破内界膜的内皮细胞细胞核数目分别为（0．19±0．09）个、（24．89±2．03）个、（23．65±2．15）个和（8．83±1．12）个,表明VEGFsiRNA质粒转染组小鼠的新生血管内皮细胞数明显低于模型对照组和空载体组,差异均有统计学意义（q=5．67、q=4．97,P〈0．01）。Real-time PCR检测表明,正常对照组小鼠视网膜中仅见弱的VEGF mRNA表达,而模型对照组与空载体组VEGF mRNA表达量为正常对照组的52．3倍和36．7倍,VEGF siRNA质粒转染组小鼠视网膜VEGF mRNA的表达量为正常对照组的3．5倍,明显低于模型对照组与空载体组。VEGF siRNA对VEGF mRNA的抑制率为43．39％。免疫荧光染色显示,正常对照组小鼠VEGF蛋白呈弱阳性表达,模型对照组和空载体组VEGF小鼠视网膜中VEGF蛋白表达呈强阳性,VEGF siRNA质粒转染组VEGF蛋白表达明显减弱。结论玻璃体腔注射VEGF siRNA表达质粒可有效抑制C57BL／6J小鼠氧诱导视网膜病变模型新生血管的形成。     

Bevacizumab抑制高氧诱导新生小鼠视网膜新生血管的实验研究

目的 探讨血管内皮生长因子(vascular endothelial growth factor,VEGF)的单克隆抗体Bevacizumab(Avastin)对视网膜新生血管的抑制作用.方法 80只7 d龄清洁级C57BL/6小鼠随机分为4组,即空白对照组、高氧实验组、小剂量实验组和大剂量实验组,建立高氧诱导新生小鼠产生视网膜新生血管的动物模型,分别对小剂量实验组和大剂量实验组行玻璃体注射Bevacizumab(25 g·L-1)0.5μL、1.0μL,免疫组织化学染色法观察VEGF在视网膜各层的表达,应用CD31计算突破视网膜内界膜的新生血管内皮细胞核数,评价该药对视网膜新生血管的抑制作用.电镜观察该药对视网膜超微结构的影响.结果 VEGF在各组视网膜中均有表达,在高氧组表达明显增加,两给药组表达相对较弱,空白对照组最弱.空白对照组、高氧实验组、小剂量实验组及大剂量实验组突破视网膜内界膜的新生血管内皮细胞核数分别为(0.20±0.42)个、(16.80±6.05)个、(3.90±1.52)个、(5.10±2.88)个,统计学处理结果表明两给药组分别与高氧实验组比较差异均有显著统计学意义(P均<0.01),而两给药组之间差异无统计学意义(P>0.05).透射电镜检查显示两给药组视网膜超微结构与高氧实验组相比损伤较轻.结论 Bevacizumab能有效抑制视网膜新生血管的形成,并在一定程度上对缺氧造成的视网膜超微结构的损伤具有预防作用.     

血管内皮生长因子受体KDR基因胞外段1-3区基因转染抑制氧诱导小鼠视网膜新生血管的研究

目的 评价脂质体介导的血管内皮生长因子受体KDR基因胞外段1-3区(KDRn3)基因转染抑制氧诱导的视网膜新生血管的效果.方法 选1周龄C57Bl/6N小鼠置于氧浓度为75%±2%的氧箱中5 d.回到正常环境中诱导视网膜新生血管模型.在小鼠离开氧箱的当日,向转染组小鼠玻璃体腔注射脂质体pEGFP-N1/KDRn3复合物1 μl;脂质体对照组注射等量脂质体;空白对照组小鼠注射等量PBS.回到正常环境中后5 d,采用视网膜铺片及视网膜冰冻切片在激光共聚焦显微镜下观察绿色荧光蛋白在视网膜的表达;采用荧光标记的右旋糖酐血管灌注下视网膜铺片方法观察视网膜新生血管的分布并测量无灌注区面积;组织学切片观察比较突破视网膜内界膜的血管内皮细胞数量.多组比较采用方差分析,有统计意义后进行两两比较的q检验.结果 转染组视网膜铺片见视网膜局部散在点状绿色荧光信号,空白对照组与脂质体对照组未见绿色荧光信号;视网膜冰冻切片见转染组视网膜神经节细胞层、内核层部分细胞胞质内见绿色荧光表达,空白对照组与脂质体对照组视网膜各层未见绿色荧光表达;视网膜铺片观察可见空白对照组与脂质体对照组在无灌注区边缘均可见新生血管芽及荧光渗漏,转染组见新生血管芽明显减少,生后第17天A、B、C 3组新生血管模型小鼠各组视网膜无灌注区面积分别为(1.33±0.49)、(2.75±0.70)、(2.12±0.35)mm2,组间比较差异有统计学意义(F=17.61,P＜0.01＝.正常对照组及A、B、C组视网膜表面突破内界膜的血管内皮细胞核计数分别为0.20±0.51、13.58±2.48、23.05±3.40及21.70±2.89,组间比较差异有统计学意义(F=1085.25,P＜0.05＝.结论 pEGFP-N1/KDRn3基因转染可不同程度抑制氧诱导C57,Bl/6J小鼠视网膜新生血管的生长.

Abstract：

Objective To evaluate the effect of liposome mediated plasmids KDRn3 injected into the vitreous to inhibit experimental retinal neovascularization. Methods One-week-old C57BL/6N mice were exposed to 75% ± 2% oxygen for 5 days, then returned to the room air to induce retinal neovascularization. Cationic liposome mediated KDRn3 comp-lex (1 μl) was injected into the vitreous in the treatment group. PBS 1 μl or liposome were injected in the control group. The pEGFP-N1/ KDRn3 expression was observed by using fluorescence microscope. Retinal neovascularization was evaluated by counting the number of vascular endothelial cell nuclei on the vitreal side of the inner limiting membrane of the retina and measuring the areas of non-perfusionsin in central retina. Results KDRn3 protein was expressed both in the ganglion layer and in the inner layer. Retinal wholemount preparation of retinal neovascular animal model showed that prominent neovascular tuft and fluorescein leakage and large areas of non-perfusionsin in central retina. Fewer neovascular tufts and fewer areas of non-perfusionsin could be seen after pEGFP-N1/KDRn3 injection. There were statistic differences between control group and pEGFP-N1/ KDRn3 injecting group with the number of vascular endothelial cell nuclei on the vitreal side of the inner limiting membrane of the retina(0. 20 ±0. 51, 13. 58 ±2. 48,23. 05 ±3. 40,21. 70 ± 2. 89;F = 1085. 25, P ＜ 0. 05 ) and the areas of non-perfusionsin in central retina [(1. 33 ± 0. 49 ) , ( 2. 75 ± 0. 70 ) , ( 2. 12 ± 0. 35) mm2; F = 17. 61 , P ＜ 0. 01] . Conclusion pEGFP-N1/KDRn3 gene transfer can inhibit retinal neovascularisation in C57Bl/6J mice of ischaemia-induced retinal neovascularisation on some extent.     

人血管内皮抑素腺病毒注射液抑制大鼠脉络膜新生血管实验研究

目的:探讨人血管内皮抑素腺病毒注射液(Ad-Es)玻璃体注射对半导体激光诱导的BN(Brown Norway)大鼠脉络膜新生血管(choroidal neovascularization,CNV)的抑制作用.方法: 雄性BN大鼠30只,右眼眼底采用激光光凝建立CNV模型,按随机数字表法分为三组:单次给药组、重复给药组及生理盐水对照组.光凝后21d,单次给药组玻璃体腔内注射Ad-Es 0.01mL;重复给药组玻璃体腔内注射Ad-Es 0.01mL,并于1wk后重复给药;生理盐水对照组玻璃体腔内注射生理盐水0.01mL.观察各组末次给药后7d荧光眼底血管造影荧光素渗漏情况,应用激光共焦显微镜下脉络膜血管平铺法测量各组CNV面积,光镜下观察组织细胞学变化,免疫组织化学检测CNV组织中CD105的表达.结果:FFA造影显示给药组渗漏发生率明显低于生理盐水对照组,重复给药组渗漏发生率低于单次给药组,差异均有统计学意义(P<0.05);激光共焦显微镜下CNV定量分析显示给药组CNV面积显著低于对照组,重复给药组CNV面积低于单次给药组,差异均有统计学意义(P<0.05).光镜下光凝部位新生血管内皮细胞数,给药组明显低于对照组,重复给药组低于单次给药组;CNV组织中CD105的表达,给药组明显低于生理盐水组,重复给药组低于单次给药组.结论:Ad-Es可以有效抑制动物模型的CNV生成,重复给药组抑制效果优于单次给药组,为治疗CNV提供了一种可能的新途径.     

VEGI基因转移抑制角膜新生血管的实验研究

目的:探讨以阳离子脂质体介导重组人VEGI基因转移对角膜新生血管(corneal neovascularization,CNV)的抑制作用。方法:角膜缝线法制作兔CNV模型,用结膜下注射的方法将阳离子脂质体包裹的VEGI重组质粒(pcDNA4-VEGI)转染入兔角膜,裂隙灯显微镜下观察记录各组兔CNV长出的时间、长度和数量,并分别于基因转染后3,7,14及21d以免疫组织化学方法观察VEGI基因表达情况,观察其对CNV的抑制作用。结果:基因转染组CNV平均出现时间为6.3d,对照组分别为3.1,3.2,3.2d不等,差异有统计学意义(F=39.838,P<0.01);基因转染后3d,转染组实验兔未出现CNV,对照组已有部分兔眼出现CNV;转染后第7d,转染组实验兔的CNV纤细,累及钟点数局限于缝线周围,对照组兔的CNV最长为2.9mm,血管密集;转染后第14d,转染组兔CNV最长达4.0mm,对照组新生血管最长达6.4mm,累及钟点数为3.2个;各时间段基因转染组CNV长度、平均面积与对照组相比,差异均有统计学意义(q=17.386,P<0.01)。免疫组织化学显示角膜上皮、基质、新生血管管壁细胞的VEGI表达阳性。各实验指标与对照组比较,差异有统计学意义(均P<0.05)。结论:VEGI基因对CNV有抑制作用。     

血管能抑素基因转移抑制视网膜新生血管的实验研究

目的 观察血管能抑素真核表达质粒(pCMV-HA)对小鼠视网膜新生血管RNV形成的抑制作用.方法 将鼠龄为7 d的56只C57BL/6J新生小鼠随机分为正常对照组、氧诱导视网膜病变(OIR)模型组、治疗组和空载体组,每组14只.后3组小鼠置于(75±2)%浓度的氧环境中饲养5 d后,回到正常空气环境中建立氧诱导的RNV动物模型.治疗组小鼠在出生后第12天出氧箱时行玻璃体腔注射血管能抑素pCMV-HA,空载体组注射等量空质粒.出生后第17天行伊凡思蓝(Evans blue)灌注血管造影视网膜铺片观察血管变化.石蜡切片行苏木精-伊红染色,光学显微镜下观察并计数突破视网膜内界膜的血管内皮细胞核数.结果 视网膜铺片结果显示,治疗组较OIR模型组和空载体组视网膜血管分布均匀,新生血管和无灌注区显著减少.治疗组突破内界膜的内皮细胞核数与OIR模型组及空载体组比较,差异有统计学意义(F=39.006,P<0.001).结论 血管能抑素pCMV-HA对氧诱导的RNV有显著的抑制作用.     

重组腺病毒载体介导色素上皮衍生因子基因抑制视网膜新生血管形成

目的 观察重组腺病毒载体介导色素上皮衍生因子（PEDF）基因对视网膜新生血管（RNV）发生的影响。方法 将20只鼠龄7 d 的Spraque-Dawley大鼠建立模型后随机分为2组，分别于出生后14 d 行玻璃体内注射空白腺病毒载体（AV-Blank组）及编码PEDF基因的重组腺病毒载体（AV-PEDF组），采用RNV内皮细胞计数、运用逆转录聚合酶链反应（RT-PCR）和免疫组织化学法检测玻璃体、视网膜中PEDF基因及其蛋白表达的变化。结果 注射药物后AV-PEDF组视网膜的新生血管数较AV-Blank组明显减少（t＝42.009，P＜0.001）；视网膜PEDF蛋白的表达较AV-Blank组明显增加（t=36.638，P＜0.001）；玻璃体组织中的PEDF mRNA表达量也较AV-Blank组明显增加（t=9.128，P＜0.001）。结论 重组腺病毒载体介导的PEDF基因可上调大鼠RNV眼玻璃体及视网膜组织中PEDF的表达；推测PEDF的表达可能与RNV的抑制与消退相关。     

Inhibition of retinal angiogenesis by PEDF

AIM: To investigate the effect of PEDF on retinal neovascularization in mice. METHODS: 40 7-day-old C57BL/6J mice was exposed to 750mL/L oxygen for 5 days and then to normal situation to produce the murine model of oxygen-induced retinopathy(OIR). One eye of the mouse was regarded as experimental one and the other served as control. Eyes in experimental group received intravitreal injection of PEDF and eyes in control group received intravitreal injection of PBS at postnatal day 12. All mice were executed at postnatal day 17. The changes of retinal vessels of mice were observed by ADPase histochemical technique. The inhibitory effect of PEDF on retinal neovascularization was evaluated by counting the endotheliocyte nuclei of new vessels which extended from retina to vitreous in the tissue slice of HE staining. RESULTS: Neovascularization was reduced, retinal blood vessels distributed regularly and non-perfusion areas were not found in eyes of experimental group compared with control group. The number of endotheliocyte nuclei of new vessels extending from retina to vitreous was significantly less in the eyes of experimental group (10.18±1.74) than that in control group (38.89±2.98) (P <0.01). Retinal toxicity and inflammatory reactions were not found in tissue slice. CONCLUSION: PEDF inhibits retinal angiogenesis in OIR and the feasibility should be determined for use of PEDF in ocular angiogenesis treatment.     

PEDF抑制鼠视网膜新生血管的实验研究(英文)

目的:观察PEDF对氧诱导的血管增生性视网膜病变动物模型视网膜新生血管的抑制作用。方法:40只7日龄的C57BL/6J新生鼠暴露在750mL/L高氧环境中,然后回到正常空气中建立氧诱导的血管增生性视网膜病变的动物模型。随机取1眼为实验眼,在出氧箱时(12d)玻璃体腔注射PEDF,另1眼为对照组,玻璃体腔注射PBS。所有小鼠均于17d处死,视网膜铺片,ADP酶染色观察视网膜血管情况。HE染色,在光学显微镜下观察并计数突破视网膜内界膜的血管内皮细胞细胞核数目。结果:与对照组相比,实验组视网膜血管分布规则,未见明显的无灌注区形成;实验组突破内界膜的内皮细胞细胞核数目(10.18±1.74)比对照组(38.89±2.98)明显减少(P<0.01) ;组织切片未见视网膜毒性及炎症反应。结论:PEDF能够有效抑制视网膜新生血管的生成。     

Inhibition of retinal angiogenesis by peptides derived from thrombospondin-1

PURPOSE: Thrombospondin (TSP)1 is a tumor suppressor with activity that is associated with its ability to inhibit neovascularization. Previous studies have mapped this antiangiogenic activity to the type 1 repeats and the amino-terminal portion of the molecule within the procollagen-like domain. The present study was performed to investigate the ability of TSP-1 and peptides derived from the type 1 repeats to inhibit retinal angiogenesis. METHODS: TSP-1 and peptides with tryptophan-rich, heparin-binding sequences and transforming growth factor (TGF)-beta1 activation sequences were evaluated in two models of retinal angiogenesis: a retinal explant assay and a rat model of retinopathy of prematurity (ROP). RESULTS: Platelet-derived TSP-1 inhibited angiogenesis in both experimental models. Peptides from the native TSP-1 sequence, which contained both the tryptophan-rich repeat and the TGF-beta1 activation sequence, were the most potent inhibitors of endothelial cell outgrowth in the retinal explant assay. In contrast, a peptide containing only the tryptophan-rich, heparin-binding sequence was most active in inhibiting neovascular disease in the rat ROP model. CONCLUSIONS: These results indicate that the type 1 repeats of TSP-1 contain two subdomains that may independently influence the process of neovascularization, and that peptides derived from these type 1 repeats may be promising pharmacologic agents for treatment of retinal angiogenesis.     

Light-induced retinal damage in mice carrying a mutated SOD I gene

Transgenic mice expressing mutated mouse Cu/Zn superoxide dismutase (SOD I), corresponding to a mutation associated with familial amyotrophic lateral sclerosis, develop a fatal motorneuron degeneration that resembles the human disease. The biochemical properties of some mutant SOD I enzymes indicate that a gain of catalytic functions, (such as increased peroxidase activity) may be the pathologic factor(s). However, at the present time there is little in vivo evidence that a mutation-induced change in the catalytic activity of SOD I is directly involved in neuronal cell death or that vulnerability to cell death is related to the level of functional/metabolic activity of cells carrying mutated SOD I. In pigmented mice carrying the G86R mutation of mouse SOD I, exposure to constant bright light for 20 days caused a diminution of electroretinographic activity and specific degeneration of photoreceptor cells, while no pathological effects were seen in transgenic littermates not exposed to bright light or in light exposed non-transgenic littermates. These findings are the first to indicate that one mechanism for neuronal cell death by mutated SOD I is use-dependent and/or related to metabolic activity, and therefore may be due to a gain in function of catalytic activities involving superoxide/hydrogen peroxide. The light-exposure pathology in this transgenic mouse model indicates an essential role for SOD I in the protection of photoreceptors from light-damage.     

Inhibition of retinal angiogenesis by gold nanoparticles via inducing autophagy

AIM: To investigate the effect of gold nanoparticles on retinal angiogenesis in vitro and in vivo, and to reveal the possible mechanism. METHODS: Seed growth method was used to synthesize gold nanoparticles (GNPs). The size, zeta potential, absorption spectrum and morphology of GNPs were identified using Malvern Nano-ZS, multimode reader (BioTek synergy2) and transmission electron microscope. Cell viability was analyzed using cell counting kit-8 method and cell growth was assessed with EdU kit. Transwell chamber was used to investigate cell migration. Tube formation method was used to assess the angiogenic property in vitro. Oxygen induced retinopathy (OIR) model was used to investigate the effect of GNPs on retinal angiogenesis. Confocal microscope and Western blot were used to study the possible mechanism of GNPs inhibited angiogenesis. RESULTS: The GNPs synthesized were uniform and well dispersed. GNPs of 10 μg/mL and 20 μg/mL were able to inhibit human umbilical vein endothelial cells proliferation (50% and 72% separately, P<0.001), migration (54% and 83% separately, P<0.001) and tube formation (52% and 90% separately, P<0.001). Further data showed that GNPs were able to improve the retinopathy in an OIR model. The possible mechanism might be that GNPs were able to induce autophagy significantly (P<0.05). CONCLUSION: The present study suggests that GNPs are able to inhibit retinal neovascularization in vitro and in vivo. GNPs might be a potential nanomedicine for the treatment of retinal angiogenesis.     

Reduced retinal angiogenesis in MMP-2-deficient mice

PURPOSE: To study the putative role of endogenous matrix metalloproteinases (MMPs) in retinal neovascularization, an established mouse model was used to compare the retinal neovascularization observed in wild-type mice with that in mice without the MMP-2 or -9 genes. METHODS: C57Bl/6 (MMP-2(+/+) and -9(+/+)), MMP-2-deficient (MMP-2(-/-)), and MMP-9-deficient (MMP-9(-/-)) mice were used. After oxygen-induced retinopathy was induced in the mice, their eyes were rapidly removed and frozen in optimal cutting temperature embedding compound. Sections were histochemically stained with specific markers for vascular cells and angiogenesis-related factors. The area of new retinal vessels was measured using image-analysis software and compared between groups. RESULTS: Retinal neovascularization was not significantly different between wild-type and MMP-9(-/-) mice. The MMP-2(-/-) mice had significantly less extraretinal neovascularization than did wild-type mice. The mean number of extraretinal neovascular buds per cross section was significantly lower in MMP-2(-/-) mice than in wild-type mice (P < 0.05). The expression of other angiogenesis-related factors, vascular endothelial growth factor and pigment epithelium-derived factor, was not different between wild-type and MMP-2(-/-) mice. CONCLUSIONS: MMP-2 may be essential in the regulation of retinal neovascularization. Pharmacologic intervention using MMP inhibitors may be a future therapeutic approach for angiogenic retinal diseases.