非编码RNA与青光眼的研究进展

青光眼是一种不可逆的、进行性的视神经退行性疾病,是全世界第2位致盲性眼病。近年来研究发现,青光眼的发病机制复杂,非编码RNA在青光眼的发生、发展过程中起重要作用,包括微小RNA、长链非编码RNA以及环状RNA,这些都有望成为青光眼诊断或治疗的新靶点,给青光眼的诊断、治疗提供了新的思路和方法。本文将针对非编码RNA与青光眼相关的研究进展进行综述,以期对临床科研提供参考。     

小梁网细胞外基质与原发性开角型青光眼的病因研究

小梁网细胞外基质与原发性开角型青光眼的病因研究陈林闻毅颐广州市第二医院眼科（５１０１５０）小梁网是小梁细胞贴附于小梁柱上形成的筛网状结构。房水是通过网孔引流的。房水引流通畅与否直接与网孔大小有关。小梁网细胞外基质（ＥｘｔｒａｃｅｌｕｌａｒＭａｔｒｉ...     

SIRT1调节人小梁网细胞中lncRNA相关信号通路的初步研究

目的:探讨沉默信息调节因子2相关酶1（SIRT1）调节人小梁网细胞功能的可能通路机制。方法:实验研究。分别将SIRT1过表达慢病毒（SIRT1过表达组）和对照慢病毒（空载体对照组）按照最佳感染复数转染人小梁网细胞系,提取两组样本的总RNA进行长链非编码RNA（lncRNA）芯片检测。通过生物信息学技术对芯片差异性lnc...     

整合素在人眼小梁网组织中的表达及意义的研究进展

整合素是一类细胞膜表面的糖蛋白受体家族分子，在小梁网组织中表达多种整合素亚单位。可以和细胞外基质结合并调节基质金属蛋白酶的表达。影响小梁网内环境的稳定，改变房水外流阻力。本文就整合素与小梁网组织的关系作一综述。     

小梁网细胞氧化应激在青光眼发病中的研究进展

青光眼是一种常见的不可逆性致盲眼病,病理性眼压升高为主要临床特征。眼压的形成与房水循环密切相关,房水动力学异常,会引起病理性眼压升高。小梁网是房水外流通道的主要组成部分,对维持正常眼压起到非常关键的作用。氧化应激是导致青光眼眼压升高的直接危险因素,表现为氧化与抗氧化作用的失衡。小梁网细胞氧化应激可能导致细胞外基质的沉积与退行性变,使细胞发生自噬和衰老,造成小梁网细胞功能障碍,最终导致房水外流阻力增大,引起病理性眼压升高。本文将针对小梁网细胞氧化应激与青光眼关系的研究进展进行综述,以期为进一步的临床研究提供依据,为探讨青光眼的发病机制、预防及治疗青光眼提供参考。     

非编码RNA在葡萄膜炎发生发展过程中的调控作用研究进展

非编码RNA（non-coding RNA,ncRNA）是真核细胞中一类不编码蛋白质但具有重要生物学功能的RNA分子,具有调控转录翻译过程、维持mRNA和蛋白质稳定、剪切和修饰RNA等重要的生物学功能,可参与胚胎发育、组织分化等基本的生命活动,以及调控疾病的发生和发展过程。越来越多的研究显示,ncRNA与葡萄膜炎发病关系密切相关,为葡萄膜炎治疗提供了新的思路。本文就ncRNA在葡萄膜炎发生发展过程中的调控作用研究进展进行综述。     

非穿透小梁切除术与传统小梁切除术治疗青光眼

我院 2 0 0 0年 2月～ 2 0 0 1年 12月行非传统小梁切除术(观察组 ) 18例 2 6眼 ,传统小梁切除术 (对照组 ) 19例 2 6眼。就两者的手术方式、手术效果、降压机制及并发症进行对比分析 ,现报告如下。1　资料和方法1.1　一般资料　观察组 18例 2 6眼 ,男 10例 ,女 8例 ,年龄7～ 74岁 ,平均 4 0 .6 5岁± 18.16岁 ;对照组 19例 2 6眼 ,男12例 ,女 7例 ,年龄 7～ 76岁 ,平均 4 3.18± 2 0 .14岁。观察组2 6眼中闭角型青光眼 10眼 ,开角型 7眼 ,青少年型 2眼 ,外伤性 3眼 ,新生血管性 2眼 ,绝对期青光眼 2眼 ;对照组 2 6眼中闭角型青光眼 9眼 ,开…     

青光眼非穿透性小梁切除术

非穿透性小梁切除术(NonpenetratingTrabeculeclomyNPT)是一种新的滤过性手术方法,近年来国外学者已用于临床,国内尚未见报道,其手术的目的是针对开角型青光眼眼压升高的病因,去掉阻碍房水外流巩膜、近小管组织和Schlemm氏管外壁,避免术中因穿透前房发生眼压突然下降,术后浅前房、脉络膜脱离、眼压不稳、前房积血等并发症〔1～3〕。1.手术方法〔4〕(1)制作以上方穹窿为基底的结膜瓣;(2)作5×4mm矩形巩膜瓣,深约1/2巩膜厚度,将其剥离至透明角膜1mm内;(3)在矩形巩膜瓣下作三角形巩膜切除,深达90%巩膜度,于三角瓣基底部两边各作一条长约2mm…     

糖皮质激素对小梁网的作用研究进展

应用糖皮质激素可引起眼压升高，它与原发性开角型青光眼关系密切。糖皮质激素对小梁网的作用可作为一个良好模型用于研究青光眼的发病机制。糖皮质激素对小梁网的作用是多方面的，它包括细胞外基质、细胞膜、细胞骨架及细胞核的多重变化。糖皮质激素受体的分子机制的新发现有助于从受体角度了解青光眼的发病机制。     

小梁网异常与原发性开角型青光眼的关系

原发性开角型青光眼中小梁网细胞结构和功能发生异常, 房水外排阻力增大从而形成病理性高眼压。小梁网细胞在转化生长因子β(TGF-β)介导的Rho-GTPase途径作用下, 细胞骨架改变, 形成交联肌动蛋白网络, 在TGF-β介导经典Smad核传导通路以及非经典Smad途径作用下, 细胞外基质堆积, 形成交联化。通过细胞-基质相互作用, 造成小梁网硬度增大, 顺应性减弱。线粒体和溶酶体长期受到外源性和内源性诱导的活性氧自由基(ROS)攻击, 细胞老化加剧, 水解组织蛋白酶释放, 自噬通量下降, 细胞凋亡激活。本综述探讨小梁网细胞、微环境及其相互影响机制, 为进一步探究原发性开角型青光眼发病机制提供参考。(国际眼科纵览, 2022, 46:150-156)     

维拉帕米对牛眼小梁细胞合成细胞外基质的影响

目的 探讨维拉帕米(Verapamil)对牛眼小梁细胞(BTMC)合成Ⅰ、Ⅲ、Ⅳ型胶原、纤维连接蛋白、透明质酸的影响。方法 采用免疫组化结合计算机图像分析和放免技术检测等于和低于0.01 mg/ml维拉帕米对BTMC合成胶原、纤维连接蛋白、透明质酸的影响。结果 0.001、0.005、0.01mg/ml维拉帕米可质量浓度依赖性抑制Ⅰ、Ⅲ型胶原、纤维连接蛋白的合成(P<0.05),而促进透明质酸的合成(P<0.05)。0.005、0.01mg/ml维拉帕米可质量浓度依赖性抑制Ⅳ型胶原(P<0.05),而0.001mg/ml维拉帕米无此作用(P>0.05)。结论 维拉帕米可通过抑制细胞外基质在小梁网异常沉积,减少房水外流阻力,有望在发病学环节上治疗原发性开角型青光眼。     

The matricellular protein SPARC is expressed in human trabecular meshwork

PURPOSE: This investigation was undertaken to determine whether the matricellular protein SPARC is expressed in the human trabecular meshwork (TM) and cultured human trabecular meshwork cells. METHODS: Human donor trabecular meshwork and cultured cells obtained from trabecular meshwork were used in this study. Total RNA was obtained from TM and cultured TM endothelial cells, and RT-PCR was done with primers specific for SPARC. Western blotting was performed on donor TMs using an anti-SPARC monoclonal antibody prepared against rHuSPARC. Confocal microscopy was used to determine the distribution of SPARC in human anterior segments, and immunofluorescence on cultured TM cells was performed with the anti-SPARC antibody. RESULTS: SPARC mRNA was expressed both in TM and in cultured TM cells. Immunoblotting for SPARC showed a doublet with a molecular mass approximately 43 kDa. The ratio of the doublet bands varied with each of the samples; some of the cultured cells and the tissue samples exhibited more of the upper band, and other cultured cells contained almost equal amounts of the two bands. The upper band was shown to be a glycosylated form of SPARC. Immunofluorescence showed that SPARC was expressed in the cultured TM, and confocal microscopy with the anti-SPARC antibody demonstrated the presence of this protein in the TM and in other tissues in the anterior segment. CONCLUSIONS: Our data conclusively show that SPARC mRNA and protein are present in non-glaucomatous TM tissue and in cultured TM cells. Because of its effect on matrix metalloproteinases, SPARC may play a role in the regulation of intraocular pressure.     

The effect of TGF-beta2 on human trabecular meshwork extracellular proteolytic system

Our study aimed to investigate whether transforming growth factor-beta2 (TGF-beta2), increased in the aqueous humor of eyes with primary open angle glaucoma (POAG), can affect factors responsible for the activity of matrix metalloproteinases (MMPs) in human trabecular cell cultures. With this goal in mind cultures of human trabecular meshwork (hTM) cells derived from 8 donors were treated with TGF-beta2 for 24, 36 and 48 hr. Influence of TGF-beta2 on expression of MMP-2, MMP-9, membrane type 1-MMP (MT1-MMP) and plasminogen activator inhibitor-1 (PAI-1) was examined using RT-PCR, Northern Blot, Western Blot and zymography. The influence of TGF-beta2 treatment on PAI-1 expression was also investigated using immunohistochemistry. It appeared that treatment with TGF-beta2 significantly increased expression of the proform of MMP-2, whereas the active form was not detectable. MMP-9 and MT1-MMP expression were not influenced by TGF-beta2 treatment. There was, however, a significant increase in PAI-1 expression. To investigate whether transformation of the proform of MMP-2 to the active form was inhibited by PAI-1, the influence of treatment with TGF-beta2 and a PAI-1 neutralizing antibody on MMP-2 was investigated using zymogram method. With this treatment protocol the active form of MMP-2 was clearly visible, indicating that TGF-beta2 enhancement of the PAI-1-expression decreases MMP activity. Inhibition of MMP activity through elevated levels of TGF-beta2 might contribute to the increase in ECM in the trabecular meshwork of glaucomatous eyes.     

Mechanobiology of trabecular meshwork cells

Trabecular meshwork (TM) cells likely play a key role in regulating outflow facility and hence intraocular pressure. They function in a dynamic environment subjected to variations in mechanical and fluid shear forces. Because the extent of mechanical stress on the trabecular meshwork is dependent on the intraocular pressure, the behavior of TM cells under mechanical strain may suggest mechanisms for how outflow facility is regulated. Studies have demonstrated that TM cells respond in a variety of ways to mechanical loads, including increased extracellular matrix turnover, altered gene expression, cytokine release, and altered signal transduction. This review highlights some of the considerations and limitations of studying the mechanobiology of TM cells.     

小梁细胞表达的miRNA研究新进展

ｍｉＲＮＡ是一种长约２２个核苷酸的非编码蛋白质的单链小ＲＮＡ,其对基因的调控主要是在转录后和翻译水平来调节基因表达。目前发现与眼部相关的ｍｉＲＮＡ已达上百种,有不少研究旨在探索ｍｉＲＮＡ在人小梁细胞上的表达及其与靶基因之间的调控机制,为进一步阐述青光眼的发病机制及其诊断、治疗提供更好的理论依据。近年来,有关ｍｉＲＮＡ与眼部组织发育、眼部疾病关系的探讨已成为眼科领域研究热点之一。本文就小梁细胞表达的ｍｉＲＮＡ研究最新进展作一综述。     

小梁网的干细胞移植治疗原发性开角型青光眼的研究进展

原发性开角型青光眼(primary open angle glaucoma,POAG)是以持续性眼压增高导致视神经损伤为主要临床表现的一种疾病,其发病机制复杂,尚未明确,现阶段临床治疗相对困难。影响眼内压(intraocular pressure,IOP)高低的重要因素是房水引流是否通畅,而房水引流途径中小梁网(trabecular meshwork,TM)起重要调控作用。TM细胞的形态、数量、结构和功能改变均可使房水外流阻力增大,从而导致IOP升高。研究证实诱导多功能干细胞(induced pluripotent stem cells,iPSCs)、骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)和脂肪干细胞(adipose-derived stem cells,ADSCs)已被用于TM细胞的分化和再生,为POAG小梁网的干细胞替代治疗提供可靠的细胞来源。近年研究发现,小梁网干细胞(trabecular meshwork stem cells,TMSCs)在分化为TM细胞方面具有绝对优势,为细胞移植治疗青光眼提供新的靶向,这标志着干细胞治疗POAG进入一个新纪元,为青光眼治疗带来新的曙光。本文将对不同种类干细胞的小梁网移植进行综述,为细胞移植治疗POAG提供新思路。     

Apoptosis in the iris and trabecular meshwork of medically treated and untreated primary open angle glaucoma patients

AIM: To compare the trabecular meshwork (TM) and iris apoptosis of treated and untreated primary open angle glaucoma (POAG) patients.METHODS: Eight treatment-naive, newly diagnosed (group 1) and 11 medicaly treated (group 2) patients with POAG were included in the study. Each patient underwent a limbus-based trabeculectomy. The TM and peripheral iris specimens were dissected out and were snap-frozen in liquid nitrogen and stored at –80℃ until they were assayed. Apoptosis in each group was assesed by TUNEL method.RESULTS:The mean patient age was 60.6±5.8 years (53-68 years) vs 58.9±8.9 years (47-70 years) in group 1 and group 2 (P=0.859). The mean treatment time in group 2 was 22.2±7.3 months (12-34 months). Apoptotic indexes in TM and iris were significantly higher in POAG patients using medication (group 2) compared to treatment-naive POAG patients (group 1) (P=0.004, 0.015; respectively).CONCLUSION: Long term administration of topical antiglaucoma medications causes additional toxic effects on TM.     

Structural changes of the trabecular meshwork in different kinds of glaucoma

The morphology of the trabecular meshwork in three types of open angle glaucoma: primary open angle glaucoma (POAG), corticosteroid-induced glaucoma and pigmentary glaucoma (PG) are described.Ageing is one major risk factor for development of POAG. It is assumed that preexisting age-related changes of the trabecular meshwork (TM) play a role for the development of increased outflow resistance and intraocular pressure (IOP) in various types of glaucoma. These age-related changes in the TM develop concomitant with that of presbyopia. Therefore the functional relationship between ciliary muscle (CM) and TM and the age-related changes in morphology of the outflow system are described first. One main finding in the ageing TM concerns changes of the elastic fiber network and the anterior elastic tendons of the CM. There is an increase in thickness of the sheath of the elastic fibers. Cross-sections through these fibers with their sheath appear as extracellular plaques and were therefore termed “sheath derived plaques” (SD-plaques).Morphologically, the TM changes in POAG resemble that of the ageing TM, but in POAG there is a significant increase in SD-plaques compared to age-matched controls. This increase is due to fine fibrils and other components of the extracellular matrix (ECM) that adhere to the sheaths of the elastic fibers and their connections to the inner wall endothelium. In POAG eyes there is also a marked loss of TM cells, at places leading to fusion and thickening of trabecular lamellae.In steroid-induced glaucoma there is also an increase in fine fibrillar material in the subendothelial region of SC. In contrast to POAG eyes these fibrils do not adhere to the sheath of the elastic fibers but are deposited underneath the inner wall endothelium. The main finding in steroid-induced glaucoma is an accumulation of basement membrane-like material staining for type IV collagen. These accumulations are found throughout all layers of the TM.In pigmentary glaucoma loss of cells was more prominent than in POAG eyes. Presumably, this cell loss occurs after overload of TM cells with pigment granules. Denuded TM lamellae fuse and the TM collapses. In the subendothelial region of these collapsed TM areas an increase in ECM presumably due to underperfusion was observed. At other places SC was occluded and the cribriform region appeared disorganized. In most parts of the circumference of the eye, the TM cells contained pigment granules. Occlusion of TM spaces by pigment granules or cells loaden with pigment was not seen in eyes with PG.