Effect of persistent high intraocular pressure on microstructure and hydraulic permeability of trabecular meshwork

As the aqueous humor leaves the eye, it first passes through the trabecular meshwork （TM）. Increased flow resistance in this region causes elevation of intraocular pressure （IOP）, which leads to the occurrence of glaucoma. To quantitatively evaluate the effect of high IOP on the configuration and hydraulic permeability of the TM, second harmonic generation （SHG） microscopy was used to image the microstructures of the TM and adjacent tissues in control （normal） and high IOP conditions. Enucleated rabbit eyes were perfused at a pressure of 60 mmHg to achieve the high lOP. Through the anterior chamber of the eye, in situ images were obtained from different depths beneath the surface of the TM. Porosity and specific surface area of the TM in control and high IOP conditions were then calculated to estimate the effect of the high pressure on the permeability of tissue in different depths. We further photographed the histological sections of the TM and compared the in situ images. The following results were obtained in the control condition, where the region of depth was less than 55 μm with crossed branching beams and large pores in the superficial TM. The deeper meshwork is a silk-like tissue with abundant fluorescence separating the small size of pores. The total thickness of pathway tissues composed of TM and juxtacanalicular （JCT） is more than 100 p.m. After putting a high pressure on the inner wall of the eye, the TM region progressively collapses and decreases to be less than 40 μm. Fibers of the TM became dense, and the porosity at 34 μm in the high IOP condition is comparable to that at 105 μm in the control condition. As a consequent result, the permeability of the superficial TM decreases rapidly from 120 μm2 to 49.6 μm2 and that of deeper TM decreases from 1.66 μm2 to 0.57 μm2. Heterogeneity reflected by descent in permeability reduces from 12.4 μm of the control condition to 3.74 μm of the high IOP condition. The persistently high IOP makes the TM region collapse from its normal state, in which the collagen fibers of the TM are arranged in regular to maintain the physiological permeability of the outflow pathway. In the scope of pathologically high IOP, the microstructure of the TM is sensitive to pressure and hydraulic permeability can be significantly affected by IOP.

Changes in Schlemm’s canal,trabecular meshwork,and relevant parameters in the early stage after SMILE of myopia patients

AIM:To observe the changes in Schlemm’s canal(SC),trabecular meshwork(TM),and anterior chamber relevant parameters after small incision lenticule extraction(SMILE) of myopia patients.METHODS:A total of 58 eyes from 30 patients who underwent SMILE were divided into a low and moderate myopia group(group A,32 eyes) and a high myopia group(group B,26 eyes).The diameter and area of the SC,the width and thickness of TM obtained by CIRRUS HD-OCT5000,and the related anterior chamber parameters obtained by Pentacam anterior segment analysis system,accommodation amplitude(AMP) were observed pre-and postoperatively.The preoperative intraocular pressure(IOP) and postoperative correction of intraocular pressure(IOPcc) were measured.RESULTS:The diameter and area of the SC in the two groups were significantly increased postoperatively(all P<0.01).The TM width of the patients in the two groups were increased at 1mo after surgery(both P<0.01),but the TM thickness did not change(P>0.05).The corneal curvature,central anterior chamber depth,and anterior chamber volume decreased after SMILE surgery(all P<0.01).There was a weak negative correlation between the SC area change and AMP change in group A(r=-0.362,P<0.01).The postoperative IOP decreased after correction by Shah formula(P<0.05).CONCLUSION:SC and TM in myopia patients change in the early postoperative stage of SMILE and the IOP is decline.

Extracellular matrix gene expression in human trabecular meshwork cells following mechanical fluid flow stimulation

AIM: To investigate changes in extracellular matrix(ECM) gene expression in human trabecular meshwork(HTM) cells in response to mechanical fluid flow stimulation.METHODS: HTM cells were grown on a glass plate coated with 0.02% type Ⅰ collagen(COL) and exposed to shear stress(0, 0.2, 1.0 dyne/cm;) for 12 h.Changes in genes related to the ECM were evaluated by real-time reverse transcriptase-polymerase chain reaction.Phosphorylation of Smad2 protein was investigated by Western blotting.RESULTS: After mechanical stimulation, COL type 4 alpha 2, COL type 6 alpha 1, and fibronectin-1 mRNA were significantly higher than the static control(P<0.05, <0.05, and <0.01, respectively).The metalloproteinase-2 and plasminogen activator inhibitor-1 mRNA were significantly higher than the static control(P<0.05 and <0.01, respectively), while the differences in the tissue inhibitors of metalloproteinases-2 mRNA were not significant.The phosphorylation of Smad2 levels was significantly higher compared to the static control cells.CONCLUSION: Changes in the expressions of genes associated ECM metabolism result in HTM cells after mechanical stimulation.The mechanical stimulation of the aqueous humor to the trabecular meshwork may promote ECM turnover and contribute to intraocular pressure homeostasis.

Effects of HepⅡ domain peptides Ⅴ of fibronectin on corneal permeability, endothelial cells, intraocular pressure and morphology of trabecular meshwork in rats

Background Trabecular meshwork （TM） cell volume may be an important determinant of aqueous humor outflow in the eye. This study aimed to evaluate the role of Hepll domain peptides V on corneal permeability, corneal endothelial cells, intraocular pressure （lOP） and morphology of trabecular meshwork in rats. Methods The lOP of rat eyes was measured before and 3, 5, 7 and 8 hours after topical delivery of Hepll domain peptides V through intracameral injections. The peptide＇s concentration in aqueous humor was assessed by high performance liquid chromatography （HPLC）. The shape and density of endothelial cells were observed by laser confocal microscopy 8 hours, 3 and 14 days after intracameral injections of Hepll domain peptides V. The morphological changes in TM of rat eyes were assessed by transmission electron microscopy （TEM）. Results Intracameral injection of Hepll domain peptides V significantly （P 〈0.001） decreased lOP by （5.71±2.10） mmHg in rats at 5 hours after injection. There were no obvious changes of the shape and the density of corneal endothelial cells. In addition, morphological changes in the TM of rats were observed including the expansion of intercellular spaces in the juxtacanalicular meshwork, removal of extracellular material, cellular relaxation, and cytoskeleton reorganization. Conclusions Hepll domain peptides V could not penetrate cornea and was safe to corneal endothelial cells. Hepll domain peptides V could significantly decrease lOP in rat probably by disorganizing actin cytoskeleton and cell-junction in the TM.

高眼压作用下大鼠小梁网组织弹性模量的变化

目的探究高眼压持续作用不同时间下大鼠小梁网组织弹性模量的变化情况,为深入研究小梁网组织的力学特性与房水外流阻力之间的关系提供基础。方法选取18只SD雄性大鼠,体重控制在260~300 g。右眼通过烙闭上巩膜静脉建立高眼压实验组模型,左眼不做任何处理作为对照组,并分别在2周、3周、4周取下眼球后制作小梁网组织横截面冰冻切片,利用原子力显微镜对小梁网区域进行纳米压痕实验,使用Sneddon接触模型对压痕曲线进行拟合,得到高眼压作用持续不同时间下小梁网弹性模量的变化情况。结果实验组与对照组眼压差异具有显著性,说明成功建立了高眼压动物模型。2周、3周、4周实验组的小梁网弹性模量分别为(20.55±5.68)kPa、(23.98±4.42)kPa、(28.56±5.94)kPa,明显大于各自的对照组,且不同时间点3个实验组的小梁网组织弹性模量也存在统计学上的差异。结论随着高眼压的持续作用,小梁网组织弹性模量明显增大,且与作用时间呈正相关。这一发现一定程度上考虑了高眼压对小梁网力学性质的影响,为深入了解高眼压对眼球生理机制的影响提供了重要线索,所得结果对房水外流阻力增大机制的研究具有参考意义。

Morphological features of anterior segment:factors influencing intraocular pressure after cataract surgery in nanophthalmos

Purpose:To investigate the anterior segment in nanophthalmic eyes and their association with intraocular pressure after cataract surgery.Methods:Thirty-two nanophthalmic eyes(axial length[AL]<18.5 mm)in 18 patients and 35 normal eyes(21.0≤AL≤24.5 mm)in 35 controls who had undergone uneventful cataract surgery were included.Swept-source optical coherence tomography was used to compare the anterior segment structures between the two groups.The associations between the anterior segment characteristics of nanophthalmic eyes and postoperative intraocular pressure(IOP)were also investigated.Results:The IOP-lowering effect of cataract surgery was remarkably insufficient in nanophthalmic eyes.Peripheral anterior synechiae(PAS)were observed in 56%(18/32)of nanophthalmic eyes,and a characteristic boomerangshaped iris was observed in 28%(9/32).The anterior surface of the iris seemed"smoother"in nanophthalmic eyes than in normal eyes.Schlemm's canal(SC)diameter,SC area,trabecular meshwork(TM)thickness,TM width,and TM area were generally smaller in the nanophthalmic eyes.Younger age,higher preoperative IOP,broader PAS,and smaller SC area were main contributors to higher postoperative IOP.AL and SC diameter may also be of great importance in IOP prediction in patients without glaucoma surgery and PAS.Conclusions:The morphological features of the anterior segment in nanophthalmic eyes are significantly different from those of normal eyes.Influencing factors such as age,AL,preoperative IOP,extent of PAS,SC and TM size could all be prognostic for IOP after cataract surgery in nanophthalmic eyes.Trial registration:ClinicalTrails.gov,Trial registration number:NCT02182921,Registered 8 July 2014.

Reversible changes in aqueous outflow facility, hydrodynamics, and morphology following acute intraocular pressure variation in bovine eyes

Background Elevated intraocular pressure （lOP） is primarily due to increased aqueous outflow resistance, but how aqueous outflow resistance is generated and regulated are still not fully understood. The aim of this study is to determine whether changes in outflow facility, outflow pattern, and morphology following acute lOP elevation were reversible when the lOP was returned to a normal level in bovine eyes using a two-color tracer technique to label outflow patterns within the same eye. Methods Twelve fresh enucleated bovine eyes were perfused with Dulbecco＇s phosphate buffer saline （PBS） containing 5.5 mmol/L glucose （DBG） at 30 mmHg first to establish the baseline outflow facility followed by a fixed volume of red fluorescent microspheres （0.5 μm, 0.002% v/v）. After the red tracer being replaced with DBG in the anterior chamber, perfusion was continued at 7 mmHg with the same volume of green tracer, followed by a fixative. In two control groups, the eyes were constantly perfused at either 30 mmHg （n=6） or 7 mmHg （n=6） using the same methods. The outflow facility （C, pJ.min.-lmmHg-1）, was continuously recorded. Confocal images were taken along the inner wall （IW） of the aqueous plexus （AP） in frontal sections. The percent of the effective filtration length （PEFL, PEFL=IW length exhibiting tracer labeling/total length of IW） was measured. Sections with AP were processed and examined by light microscopy. The total length of IW and the length exhibiting separation （SL） in the juxtacanalicular connective tissue （JCT） were measured. A minimum of eight collector channel （CC） ostia per eye were analyzed for herniations. Results In the experimental （30-7 mmHg） group, the outflow facility was significantly higher at 7 mmHg （（4.81±1.33） #lmin-1 mmHg-1） than that at 30 mmHg （（0.99±0.15） μl.min-1 mmHg-1, P=-0.002）, corresponding to a significant increase in the PEFL （P=-0.0003）. The percent of CC ostia exhibiting herniations in the experimental group （（67.40±8.90） μl.min·-1mmHg-1） decreased significantly compared to that in the control at 30 mmHg （（94.44±3.33） μl.min-lmmHg-1, P=-0.03）, but higher than that in the control at 7 mmHg （（29.43±4.60） μl.min-1mmHg-1, P=0.01）. Washout-associated separation between the IW and JCT was found by light microscopy and percent separation length （PSL, PSL=SL/total length of IW） was decreased in the control at 30 mmHg compared to that in the experimental group and control at 7 mmHg. Conclusions The pressure-induced morphological and hydrodynamic changes were reversible. Changes （collapse of AP, separation between the JCT and IW, and herniation into CC ostia） influence the effective filtration area that regulates outflow facility.

模拟过载对猕猴眼压及视神经的影响

针对航天返回段过载环境可能对眼造成不利影响的问题,研究模拟过载对猕猴眼压及视神经的影响。12只猕猴分为A组和B组,每组6只。采用离心机模拟嫦娥号、阿波罗号过载曲线,A组以卧姿、B组以躺姿分别进行13 G和15 G重力模拟过载,2次过载暴露间隔24 h。于13 G过载前(基线)、13 G过载后、15 G过载前、后应用iCare手持式回弹眼压计测量眼压、离体UBM观察房角结构、HE染色观察小梁网及视神经改变。结果显示:与基线眼压相比,A组和B组13 G、15 G过载后眼压均下降(P<0.001,P<0.05),B组降低幅度小于A组;13 G与15 G过载后两组之间眼压降低幅度均有统计学意义(P<0.05)。B组有1只猕猴双眼出现眼压异常升高伴睫状充血等急性高眼压症状,离体UBM未观察到前房变浅及房角狭窄等异常,HE染色未发现小梁网异常;短暂眼压升高未发现视神经形态有明显异常变化。过载可能导致个别眼压异常升高,短暂过载对猕猴视神经未发现明显影响。

Ocular manifestations of central insulin resistance

Central insulin resistance, the diminished cellular sensitivity to insulin in the brain, has been implicated in diabetes mellitus, Alzheimer’s disease and other neurological disorders. However, whether and how central insulin resistance plays a role in the eye remains unclear. Here, we performed intracerebroventricular injection of S961, a potent and specific blocker of insulin receptor in adult Wistar rats to test if central insulin resistance leads to pathological changes in ocular structures. 80 mg of S961 was stereotaxically injected into the lateral ventricle of the experimental group twice at 7 days apart, whereas buffer solution was injected to the sham control group. Blood samples, intraocular pressure, trabecular meshwork morphology, ciliary body markers, retinal and optic nerve integrity, and whole genome expression patterns were then evaluated. While neither blood glucose nor serum insulin level was significantly altered in the experimental or control group, we found that injection of S961 but not buffer solution significantly increased intraocular pressure at 14 and 24 days after first injection, along with reduced porosity and aquaporin 4 expression in the trabecular meshwork, and increased tumor necrosis factor α and aquaporin 4 expression in the ciliary body. In the retina, cell density and insulin receptor expression decreased in the retinal ganglion cell layer upon S961 injection. Fundus photography revealed peripapillary atrophy with vascular dysregulation in the experimental group. These retinal changes were accompanied by upregulation of pro-inflammatory and pro-apoptotic genes, downregulation of anti-inflammatory, anti-apoptotic, and neurotrophic genes, as well as dysregulation of genes involved in insulin signaling. Optic nerve histology indicated microglial activation and changes in the expression of glial fibrillary acidic protein, tumor necrosis factor α, and aquaporin 4. Molecular pathway architecture of the retina revealed the three most significant pathways involved being inflammation/cell stress, insulin signaling, and extracellular matrix regulation relevant to neurodegeneration. There was also a multimodal crosstalk between insulin signaling derangement and inflammation-related genes. Taken together, our results indicate that blocking insulin receptor signaling in the central nervous system can lead to trabecular meshwork and ciliary body dysfunction, intraocular pressure elevation, as well as inflammation, glial activation, and apoptosis in the retina and optic nerve. Given that central insulin resistance my lead to neurodegenerative phenotype in the visual system, targeting insulin signaling may hold promise for vision disorders involving the retina and optic nerve.

电压门控性氯通道3在高眼压模型大鼠小梁网中的表达

目的:检测电压门控性氯离子通道3(ClC-3)在大鼠小梁网中的表达情况,探讨其在青光眼发病机制中的可能作用。方法:30只健康雄性大鼠。左眼作为正常对照,右眼前房内注射玻璃酸钠,每周1次,连续10周,制备高眼压模型,每次全麻后玻璃酸钠注射前采用Tono-Pen XL眼压计测量双眼眼压并记录。实验分为正常对照组、玻璃酸钠注射3周组和10周组。分别取3组大鼠的小梁网组织,采用RT-PCR法检测ClC-3mRNA表达水平,免疫组织化学法检测ClC-3蛋白的表达。结果:玻璃酸钠注射后1、3和10周,大鼠右眼眼压均较注射前增高(P<0.01),注射后1周眼压值较注射前轻微增高,注射后3周眼压较注射前明显增高,但眼压值未达到高眼压成模标准,注射后10周眼压值较注射前明显增高,达到高眼压成模标准。RT-PCR法检测,与正常对照组比较,玻璃酸钠注射3周组大鼠小梁网组织中ClC-3mRNA表达水平明显增高(t=7.88,P<0.05);玻璃酸钠注射10周组大鼠小梁网组织中ClC-3mRNA表达水平明显降低(t=15.93,P<0.05)。免疫组织化学检测,3组大鼠小梁网组织中ClC-3蛋白表达均为阳性,玻璃酸钠注射3周组大鼠小梁网组织中ClC-3蛋白表达强度较正常对照组大鼠增强,玻璃酸钠注射10周组大鼠小梁网组织中ClC-3蛋白表达强度较正常对照组大鼠减弱。结论:大鼠小梁组织中存在ClC-3的表达,ClC-3可能与小梁网的病理调节有关联,进而参与青光眼的发病。

H-1152对兔眼眼压及小梁组织超微结构的影响

目的观察H-1152对兔眼眼压以及小梁组织超微结构的影响,并探讨其作用机制。方法观察兔眼点用H-1152前后眼压变化,并用透射电镜分析兔眼小梁组织超微结构的变化。结果H-1152能明显降低兔眼眼压。局部点用10mmol/L的H-1152(50μL)后1～6h的眼压较对照组降低(P<0.05)。点药后2h下降至最低点,较处理前降低50.6%。与对照组相比,点药后1～3h眼压下降最明显。电镜下可见小梁间间隙增大,小梁组织中细胞外基质(ECM)减少。结论H-1152可有效降低兔眼眼压,其作用机制可能是通过降解小梁通道的ECM,改变小梁通道的构型,使房水排出阻力减少,眼压降低。H-1152有望成为治疗青光眼的有效药物。

青光眼患者小梁网中ONOO^-的表达及与眼压升高关系的研究

目的检测正常人和原发性急性闭角型青光眼(primary acute angle closure glaucoma,PAACG)及原发性慢性闭角型青光眼(primary chronic angle closure glaucoma,PCACG)患者小梁网组织标本中过氧亚硝基阴离子(peroxynitrite,ONOO-)的表达,探讨小梁网中ONOO-的变化、分布及与青光眼的关系。方法取正常眼6例及PAACG患者14例18只眼及PCACG患者12例15只眼小梁网组织标本,应用形态学观察,免疫组织化学方法检测小梁细胞ONOO-的标志物硝基酪氨酸(nitrotyrosine,NT)的表达,并采用计算机图像分析系统对检测结果进行分析。结果正常人的小梁网组织标本NT的表达呈弱阳性或不表达,PAACG组小梁网组织中NT呈强阳性表达,PCACG组小梁网组织中NT呈阳性表达,3组间的差异均具有统计学意义(F=25.32,P<0.01),眼压与小梁网NT着色强度呈相关关系(P<0.01)。结论正常人的小梁网细胞ONOO-微弱表达而PAACG与PCACG患者小梁网细胞ONOO-大量表达且其表达量随眼压的升高而增多,表明眼压升高可导致ONOO-过量生成,从而损伤小梁网细胞,进一步加重青光眼眼压升高。

氯离子通道2对压力应激状态下人眼小梁细胞功能的影响

目的探讨分布于小梁细胞上的氯离子通道2(ClC-2)与小梁细胞数量及功能之间的关系,以进一步了解原发性开角型青光眼的形成机制。方法首先分别利用反转录聚合酶链反应、台盼蓝染色、末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法检测不同压力,以及不同压力作用时间下小梁细胞ClC-2mRNA表达、小梁细胞活力及凋亡情况的变化;再利用RNAi技术抑制ClC-2mRNA的表达,观察一定压力及作用时间下小梁细胞活力、凋亡情况的变化。结果与0mm Hg(1mm Hg=0.133kPa)、20mm Hg相比,30mmHg及40mm Hg时,随压力作用时间的增加,ClC-2mRNA的表达明显增高,差异有统计学意义;表达最高点为24h;60mm Hg时,各时间点下ClC-2mRNA的表达较30mm Hg、40mm Hg时明显降低,差异有统计学意义,且随时间延长,ClC-2mRNA的表达逐渐下降。当40mm Hg及60mm Hg的压力持续作用一段时间后,小梁细胞活力明显降低,凋亡指数明显增加,差异有统计学意义。抑制ClC-2mRNA表达后,压力应激状态下小梁细胞活力下降及凋亡增加更显著,差异有统计学意义。结论压力应激条件下,ClC-2表达的变化与小梁细胞的活力及凋亡有一定的相关性,提示ClC-2对小梁细胞存在保护作用。

选择性激光小梁成形术对小梁网显微结构影响及降压机制研究

目的实验观察选择性激光小梁成形术(SLT)对猕猴小梁网显微结构的作用。方法健康成年恒河猴8只8眼,无眼疾,房角为开角。右眼上方180°行SLT,左眼作对照眼,术后1周,双眼行小梁切除术,做扫描电镜和透射电镜观察,自身对照SLT治疗前后小梁组织的形态学改变。结果 SLT术后弥猴眼小梁组织扫描电镜见小梁网结构完整,小梁柱层次清楚,未见凝固性损伤及热损伤,只有局部小梁架的裂隙样改变,小梁网间隙中可见较多体积较大的吞噬细胞;透射电镜见色素性小梁内皮细胞内可见部分黑色素颗粒崩解、外溢。结论 SLT对小梁组织无凝固性损伤及热损伤,可以重复治疗。

小梁切除术后滤过泡的有无与眼压的关系

分析了４８例（６８只眼）原发性青光眼小梁切除术后滤过泡与眼压的关系。随访时眼压控制在２．８ｋＰａ以下者，在滤过泡明显的１８眼中有１５眼，占８３．３３％；滤过泡扁平的２６眼中有２１眼，占８０．７７％；无滤过泡的２４眼中有１８眼，占７５％。滤过泡明显与滤过泡扁平二者之间无显著性差异。有滤过泡与无滤过泡二者之间无显著差异。结果表明：滤过泡的有无与眼压无关。

探讨影响老年性白内障术后眼压升高的因素

目的:探讨影响老年性白内障术后眼压升高的因素。方法:对选取病例用统计学方法进行分析,总结影响术后眼压升高的相关因素。结果:年龄、前房内反应(房闪)与术后第1 d眼压有相关性。结论:眼内粘弹剂的残留、小梁网滤过功能、血-房水屏障破坏可使老年性白内障眼术后眼压升高。

体外培养人眼小梁细胞Ang Ⅱ的表达

目的探讨血管紧张素Ⅱ(Ang Ⅱ)在体外培养的人眼小梁细胞(TMC)中的表达情况。方法原代和传代培养人眼TMC株,收集第3代人眼TMC用于制作细胞爬片。利用免疫组织化学染色法和Western blot法检测体外培养人眼TMC中AngⅡ蛋白的表达。结果传代培养的人眼TMC呈典型梭形,免疫组织化学检测显示体外培养的人眼TMC细胞膜和细胞质中可见AngⅡ的阳性颗粒,阴形对照片中未见有Ang Ⅱ蛋白表达。Western blot法在相对分子质量为64000处可见一明显蛋白条带,为Ang Ⅱ蛋白的阳性表达。结论Ang Ⅱ在体外培养的人眼TMC中呈阳性表达,提示AngⅡ可能参与青光眼眼压和房水循环的调节。

抗坏血酸在兔类固醇性高眼压中保护作用的研究

目的 :研究抗坏血酸在类固醇性高眼压发病中的作用。方法 :2 0只兔分为四组 ,每组 5只。观察四组实验动物眼压变化与时间关系。测定房水抗坏血酸浓度 ,眼球制作病理切片。结果 :单独使用地塞米松组兔眼压显著升高 ,房水中抗坏血酸浓度明显低于其它组 ;联合使用地塞米松及抗坏血酸眼压略有升高 ,后期有下降 ,小梁网出现轻微病理改变。结论 :局部使用皮质类固醇药物治疗时 ,同时局部给予抗坏血酸 ,可延缓和减轻类固醇性高眼压的发生。

白细胞介素-6在青光眼发病过程中的作用

青光眼是全球范围内第二位致盲性眼病,其发病原理目前尚不十分明确,治疗方面多从对症治疗、降低眼压方面进行,以降低青光眼对视神经的不可逆损伤。房水中含有大量的细胞因子,包括促炎性因子、氧化应激因子、生长因子等,这些细胞因子在青光眼发病及预后过程中均起到至关重要的作用。白细胞介素-6(interleukin-6, IL-6)作为最常见的促炎性因子之一,近年来成为众多国内外临床试验监测的对象。本文旨在综述IL-6在青光眼发病过程中的作用。

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。