姜黄素和苏拉明抑制兔RPE细胞增生的对比研究

目的 对比研究姜黄素和苏拉明对兔视网膜色素上皮(RPE)细胞增生的抑制作用.以苏拉明为对照药,探讨姜黄素防治增生性玻璃体视网膜病变(PVR)的潜在价值.方法 MTT法检测不同质量浓度姜黄素和苏拉明在各时间段对体外培养的RPE细胞增生的抑制率.相关回归分析计算两种药物各时间段的半数抑制率(IC50)剂量.流式细胞仪检测姜黄素和苏拉明对RPE细胞周期及细胞凋亡的影响,并且检测姜黄素作用不同时间后RPE细胞的凋亡率.结果 姜黄素和苏拉明对RPE细胞均有明显的抑制作用,呈时间和质量浓度依赖性.姜黄素在24、48、72及96h的IC50均明显低于苏拉明.姜黄素使RPE细胞阻滞在G0/G1期,早于苏拉明的G2/M期.姜黄素可以诱导RPE细胞凋亡,苏拉明则不能.姜黄素15μg/mL作用24、48及72h后,RPE细胞的凋亡率分别为(12.83±0.13)%、(32.27±4.51)%、(56.81±8.67)%.结论 姜黄素通过诱导RPE细胞凋亡而有效抑制其增生,比苏拉明药效强且起效快,有望成为防治PVR的理想天然药物.     

紫杉醇对体外人翼状胬肉成纤维细胞的抑制作用

目的:观察紫杉醇(PA)对体外培养人翼状胬肉成纤维细胞(HPF)增生,凋亡的影响。方法:用0～1000nmol/LPA作用于体外培养HPF的24～96h后观察不同浓度的PA对HPF的影响。MTT法检测细胞的增殖情况,流式细胞仪测定细胞的周期时相。结果:在1～1000nmol/LPA对HPF的抑制作用呈时间和剂量依赖性(P<0.05)。1,10,1000,10000nmol/L的PA作用HPF24h后,流式检测发现低浓度药物组(1～10nmol/L)主要阻止细胞在G0～G1,高浓度组(100～1000nmol/L)主要阻止细胞在G2～M期,并可见细胞凋亡。结论:PA可显著抑制HPF的增殖,使细胞周期停止在G2～M期和细胞的凋亡。     

三氧化二砷对体外培养的人视网膜色素上皮细胞作用的实验研究

目的 观察三氧化二砷（As2O3）对体外培养的人视网膜色素上皮（RPE）细胞的增生抑制及凋亡诱导作用。方法 不同浓度的As2O3理细胞，倒置显微镜下观察细胞形态，四唑盐（MTT）比色法检测人RPE细胞对As2O3的药物敏感性，流式细胞仪检测细胞周期变化和凋亡率。结果 药物处理后细胞出现凋亡形态改变。MTT比色法结果显示，As2O3作用血清组人RPE细胞后各实验组与对照组之间吸光度比较有统计学意义，药物剂量分别为：作用24h为6．25μmol／L（P=0．018）、48h为6．25μmol／L（P〈0．01）、72h为1．56μmol／L（P〈0．01）；作用无血清组细胞48h后为12．5μmol／L（P〈0．01）。流式细胞仪分析结果显示As2O3作用人RPE细胞周期改变表现为S期阻滞及G2／M期延长。As2O3处理人RPE细胞后出现凋亡峰。结论 As2O3可抑制体外培养的人RPE细胞的生长并诱导其凋亡，有望为临床防治增生性玻璃体视网膜病变（PVR）提供新的药物干预。     

维拉帕米对体外人晶状体上皮细胞增殖和黏附的抑制作用

目的:研究钙离子拮抗剂维拉帕米(verapamil,Ver)对体外培养的人晶状体上皮细胞(human lens epithelial cell,HLEC)增殖、凋亡和黏附的影响。方法:组织块法培养人晶状体上皮细胞,用Ver处理第二代人晶状体上皮细胞。MTT法观察不同浓度的Ver对HLEC增殖和黏附的影响,AO/EB双染法观察细胞形态,Annexin V-FITC/PI双染法观察细胞凋亡情况,流式细胞术(FCM)检测Ver对HLEC周期的影响。结果:组织块贴壁4~6d可见HLEC从组织块边缘长出,15~20d接近融合。随着Ver药物浓度的增加,HELC增殖率减少,以72h最为明显。FCM检测细胞周期变化时发现,G1期细胞在10,40g/L Ver(78.1±0.2,83.2±0.6)较正常组(72.0±0.9)增加(P<0.05);S期的细胞在10,40g/L Ver(10.2±0.1,8.5±0.3)较正常组(16.9±0.3)明显减少(P<0.05)。形态学观察发现,HELC在40g/LVer作用48h后发生了一系列形态改变,包括细胞核固缩、染色质边集等凋亡改变。10,20,40,80g/L的Ver可以诱导HLEC发生凋亡,且随着浓度的升高凋亡率显著升高。用药24h后HELC的贴壁量为对照组的73.2%。结论:Ver能改变细胞周期而抑制HLEC增殖、诱导细胞凋亡,并且抑制HLEC的黏附。     

银杏叶提取物对体外培养翼状胬肉成纤维细胞增殖的抑制作用

目的：研究不同浓度的银杏叶提取物（ginkgo biloba extract,GBE）对体外培养人翼状胬肉成纤维细胞(human pterygium fibroblasts,HPFs)增殖和凋亡的影响。 方法：用噻唑蓝比色法(MTT)检测不同浓度(12.5,25.0,50.0,100.0mg/L) GBE在不同作用时间(24,48,72h)对体外培养的HPFs增殖的影响。用流式细胞仪检测HPFs的细胞周期及凋亡率。 结果：MTT结果显示,GBE浓度为12.5mg/L组作用24h后对HPFs的增殖无明显抑制作用（P>0.05）,其余各时间段各组均可见明显抑制HPFs的增殖,且各组间比较差异有统计学意义(P<0.05);流式细胞仪检测发现GBE作用48h后G₀/G₁期细胞比例增加,S期细胞比例下降,计算不同浓度GBE作用下凋亡率分别为4.37%,8.14%,11.09%,15.18%,组间比较差异有统计学意义(P<0.05)。 结论：GBE对HPFs的增殖有明显抑制作用,并与用药剂量和持续时间有关。     

Bcl-2及bFGF在维拉帕米诱导人视网膜色素上皮细胞凋亡中的表达

目的探讨维拉帕米(verapamil,Ver)对体外培养的人视网膜色素上皮(retinal pigment epithelium,RPE)细胞的凋亡作用,观察凋亡过程中原癌基因蛋白质(Bcl2)和碱性成纤维细胞生长因子(baic fibroblast growth factor,bFGF)的表达变化。方法应用80mg·L-1Ver作用于体外培养的人RPE细胞12h、24h、48h,吖啶橙(acridineorange,AO)荧光染色及透射电镜观察RPE细胞凋亡;逆转录聚合酶链反应(RTPCR)检测Bcl2mRNA和bFGFmRNA表达变化。结果经Ver作用的体外培养的人RPE细胞具有典型的凋亡形态学特征:核染色质浓染、边集;细胞体积缩小。同时RPE细胞Bcl2mRNA表达下降;而bFGFmRNA表达随着作用时间延长,呈增高趋势。结论Ver可诱导体外培养人RPE细胞凋亡,凋亡过程中Bcl2表达逐渐下降,而bFGF表达增强。     

糖基化终末产物对牛视网膜毛细血管周细胞增殖及转化生长因子-β表达的影响

目的 研究糖基化终产物（AGEs）对体外培养的牛视网膜毛细血管周细胞的增殖、细胞周期和转化生长因子β（TGF-β）表达的影响。 方法 分别应用四甲基偶氮唑盐(MTT)比色分析法检测周细胞的增殖、流式细胞术分析细胞周期、免疫荧光染色法观察TGF-β蛋白的表达。 结果 AGEs能抑制体外培养的牛视网膜毛细血管周细胞的增殖；并可使细胞周期阻滞于S期，凋亡细胞数显著增多（P<0.01）；能促进周细胞TGF-β蛋白的表达。 结论 AGEs可通过抑制周细胞增殖，促进周细胞的凋亡而导致周细胞数量的减少；并可能促进周细胞分泌TGF-β而进一步加速糖尿病视网膜病变。 (中华眼底病杂志, 2006, 22: 20-23)     

苏拉明对体外培养的人视网膜色素上皮细胞增殖的影响

目的 观察苏拉明(suramin)对体外培养的人视网膜色素上皮细胞(retinalpigment epithelial cells)生长、增殖的影响。方法 以300mg·L~(-1)苏拉明作用于培养的视网膜色素上皮细胞,于不同的时间点行细胞计数,绘制生长曲线,台盼蓝染色判定细胞的活性;将不同浓度的苏拉明(0、100、200、300、400mg·L~(-1))加入RPE细胞培养液,72h后用四甲基唑盐(MTT)比色法测吸光值A,并计算不同浓度条件下的细胞增殖抑制率;流式细胞技术检测细胞周期变化。结果 苏拉明在所设浓度内均抑制RPE细胞增殖,并存在时间-效应及剂量-效应关系,最大增殖抑制率约78％,72h时IC_(50)为272mg·L~(-1)。FCM示suramin使G_2/M期细胞增加了14.2％。结论 苏拉明能抑制体外培养的人视网膜色素上皮细胞增殖,可作为防治增生性玻璃体视网膜病变(proliferative vitreoretinopathy,PVR)的候选药物作进一步研究。     

氯离子通道-3反义寡核苷酸对内皮素-1促增殖体外培养的牛角膜内皮细胞的抑制作用

目的 观察氯离子通道-3(chloride channel 3,CIC-3)反义寡核苷酸(antisense oligonucleotides,AS-ODN)对内皮素1(endothelin-1,ET-1)促增殖体外培养的牛角膜内皮细胞(bovine corneal endothelial cells,BCECs)的抑制作用.方法 BCECs细胞悬液接种培养12 h后,通过脂质体介导转染不同浓度的ClC-3寡核苷酸.体外培养BCECs 24 h后加入200 pmol·L-1 ET-1,继续培养48 h.通过倒置荧光显微镜观察BCECs寡核苷酸的摄取.采用逆转录聚合酶链反应、免疫印迹法检测ClC-3 mRNA和蛋白的表达.采用MTT法观察BCECs增殖状况,计算细胞存活率,同时应用流式细胞仪检测细胞周期时相的变化,计算细胞增殖指数.结果 寡核苷酸可被培养的BCECs摄取.ClC-3 mRNA与蛋白的表达变化呈平行关系.与不加时相比,ClC-3 AS-ODN浓度依赖性地减少BCECs ClC-3 mRNA和蛋白的表达,同样也浓度依赖性地降低BCECs MTT吸光度值(OD值)和细胞存活率.经100 mg·L-1ClC-3 ASODN处理后,与对照组相比,细胞G0/G1期细胞比例明显增高,S期及G2期细胞比例则明显降低,出现明显的凋亡峰,增殖指数明显下降.结论 ClC-3 AS-ODN可能通过减少ClC-3 mRNA和蛋白的表达,浓度依赖性抑制ET-1对体外培养BCECs的增殖作用,并使细胞周期停滞在G1期.     

缺氧诱导体外培养人视网膜色素上皮细胞凋亡

目的:了解缺氧条件下体外培养人视网膜色素上皮(retinal pigment epithelium,RPE)细胞的凋亡情况。方法:将培养的人RPE细胞置于含10mL/LO2、50mL/LCO2和940mL/LN2的培养箱内建立缺氧模型。于缺氧后1,3,6,12,24h,利用扫描电镜、透射电镜、脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(terminal-deoxynucle-otidyl transferase mediated nick end labeling,TUNEL)技术和流式细胞仪测定RPE细胞凋亡水平。结果:常氧状态下RPE细胞生长良好,几乎没有凋亡(TUNEL法测凋亡指数为1.2)。缺氧条件下,RPE细胞发生了不同程度的凋亡,缺氧后3h凋亡水平达峰值(凋亡指数为34.43)。结论:缺氧可导致体外培养的人RPE细胞凋亡,提示RPE凋亡可能参与了某些缺血缺氧性眼病的发生。     

Mitogen-activated protein kinase inhibitor,PD98059, inhibits rat retinal pigment epithelial cell replication by cell cycle arrest

PURPOSE: To investigate the effect of PD98059, a mitogen-activated protein kinase (MAPK) inhibitor, on the replication of rat cultured retinal pigment epithelial (RPE) cells. METHODS: Growth-phase rat RPE cells were exposed to various concentrations of PD98059 in serum-free F12 medium containing 0.1% dimethyl sulfoxide. Cell proliferation was assessed by cell counts using a hemocytometer. Cell viability was tested by CellTiter 96 AQueous Non-Radioactive Cell Proliferation Assay at 24 hours after PD98059 application. Hoechst 33552 and propidium iodide staining were used to assess nuclear morphology. Immunostaining with Ki67 antibody was used for cell cycle analysis because the staining patterns produced on cells are characteristic depending on their position within the cell cycle. RESULTS: PD98059 inhibited cellular proliferation of cultured rat RPE cells in a dose-dependent manner but did not induce cell death. Twenty-four hours after the application of PD98059, cultured RPE cells were not immunopositive for Ki67, indicating that their cell cycle was arrested in the G0/G1 phase. CONCLUSION: These results demonstrated that MAPK inhibition arrested cell cycle progression of rat cultured RPE cells at the G0/G1 phase. The pharmacological induction of cell cycle arrest could be a new approach to inhibit cellular proliferation in such conditions as proliferative vitreoretinopathy.     

Cyclin-dependent kinase inhibitor roscovitine induces cell cycle arrest and apoptosis in rabbit retinal pigment epithelial cells.

AIMS: Cyclin-dependent kinases (CDKs) play essential roles in the intracellular control of the cell cycle. It has been postulated that roscovitine, a potent CDK2, CDK5, and CDC2 inhibitor, might inhibit cellular proliferation by arresting the cell cycle. This in vitro study investigated the antiproliferative and apoptotic effects of roscovitine in cultured rabbit retinal pigment epithelial (RPE) cells. METHODS: Experiments using rabbit RPE from young pigmented rabbits were carried out using roscovitine dissolved in dimethylsulfoxide at concentrations ranging from 1 to 100 micromol. Cell proliferation was measured by an MTT assay. The cell cycle response of RPE cells to roscovitine was analyzed by flow cytometry of propidium iodide-stained nuclei. Proteins related to DNA damage in the RPE cells were then assayed by Western blot. RESULTS: Roscovitine inhibited proliferation of RPE cells in a dose-dependent manner. Cell cycle analysis after treatment demonstrated an accumulation of cells arrested in the S- and G2/M phases. Flow cytometry showed that 40 microM of roscovitine increased the cell population in the sub-G1 peak, which is considered a marker of cell death by apoptosis. Western blot analysis revealed Bcl-2 decreased and Bax increased after treatment of RPE cells with roscovitine. CONCLUSIONS: This study of the response of RPE cells to roscovitine demonstrated a bidirectional relationship between cell cycle control and apoptosis.     

Mechanism of growth inhibitory effect of Mitomycin-C on cultured human retinal pigment epithelial cells: apoptosis and cell cycle arrest.

PURPOSE: To investigate the therapeutic potential of Mitomycin-C (MMC) in the management of proliferative vitreoretinopathy, the antiproliferative effect of MMC on cultured human retinal pigment epithelial (RPE) cells were investigated in vitro. METHODS: Drug sensitivities of cultured human RPE cells to MMC were determined using the tetrazolium dye assay. In order to detect the presence of apoptosis, DNA fragmentation was assessed by DAPI staining, and TdT-dUTP nick-end labeling (TUNEL) assay. The relative amount of DNA fragmentation was quantified by flow cytometric analysis. To analyze the cell cycle response of RPE cells to MMC, flow cytometric analysis of propidium iodide stained nuclei was performed. The levels of proteins related to DNA damage in the RPE cells were then determined by Western blot analysis. RESULTS: MMC inhibited cell proliferation in a dose-dependent manner. The majority of RPE cells following treatment with 10 microg/ml of MMC exhibited fragmented nuclei as observed by DAPI staining and TUNEL assay. Cell cycle analysis demonstrated an accumulation of cells arrested in S and G2/M phase following treatment with 1 microg/ml of MMC. At 10 microg/ml of MMC, a dramatic increase of the cell population in the sub G1 peak, which can be considered a marker of cell death by apoptosis, was observed by flow cytometry. Western blot analysis of p53 and p21 revealed a gradual increase in the level of these proteins when RPE cells were exposed to increasing concentrations of MMC. CONCLUSIONS: This study demonstrated that the response of RPE cells to MMC was bi-directional: 1) partial arrest of the cell cycle at S, G2/M phase, and 2) induction of apoptotic cell death.     

In vitro susceptibility of newborn murine retinal cells to herpes simplex virus type 1 infection

We have investigated the in vitro susceptibility of murine neural retinal cells to infection by herpes simplex virus Type 1 (HSV-1). Retinal cells obtained from newborn C57B1/6 mice were cultured for 6 days and infected with varying doses of HSV-1. Infection was determined by ABC immunoperoxidase staining of fixed cultures for HSV-1 antigens. Retinal neurons, including amacrine cells, were highly susceptible to infection, with 100% of the multipolar neurons expressing viral antigens after 12 hr of infection. Glial cells and retinal pigment epithelial (RPE) cells also were 100% infected within 12-16 hr. Photoreceptor infection was not as fast, but all surviving photoreceptor cells and their precursors became infected by 24-48 hr postinoculation. Since embryonic chick photoreceptors are highly resistant to HSV-1, these results demonstrate that mammalian (murine) photoreceptor cells differ from avian photoreceptor cells in their susceptibility to in vitro HSV-1 infection. In addition, our current results suggest that the in vivo resistance of adult C57B1/6 mice to herpetic retinitis may not reside at the level of the individual retinal cell populations, although apparent differences in susceptibility exist among the various retinal cell subpopulations.     

反义寡核苷酸对人视网膜色素上皮细胞EGFR表达和增生抑制作用的研究

目的 研究反义寡核苷酸(ODN)对人视网膜色素上皮(RPE)细胞，表皮生长因子受体(EGFR)表达和增生的影响。方法 采用人工合成反义ODN经阳性脂质体包裹后转染人RPE细胞。用MTT和细胞周期分析检测转染ODN后对细胞的生长抑制作用，采用半定量RT-PCR法与ELISA法检测EGFR mRNA及蛋白的表达水平。结果 显示转染反义ODN 24 h后，EGFR mRNA的表达抑制率为35．2％，EGFR蛋白抑制率为66．45％。48 h后．反义EGFR ODNS对EGFR蛋白的抑制作用消失。EGFR反义ODN对RPE细胞生长增生的抑制率约为40％。细胞周期分析EGFR反义ODN作用于细胞后，细胞G0／G1期细胞数明显增多，S期细胞数相应减少，而G2 M期细胞数亦明显减少。结论 EGFR反义SON可抑制人RPE细胞的生长和EGFR mRNA及其蛋白的表达。     

姜黄素对兔视网膜色素上皮细胞增生的抑制作用

目的 探讨姜黄素对兔视网膜色素上皮（RPE）细胞增生的抑制作用及其作用机制。方法 选取第4代RPE细胞进行实验,分为姜黄素组和空白对照组,姜黄素组设10、15、20 μg/ml 3个质量浓度。噻唑蓝比色(MTT)法检测姜黄素10、15、20 μg/ml分别在24、48、72 、96 h对体外培养的RPE细胞增生的抑制率。线性回归分析计算各时间段的半数抑制率（IC50）剂量。流式细胞仪（FMC）检测姜黄素15 μg/ml作用72 h后对RPE细胞周期的影响,并且检测姜黄素15 μg/ml作用24、48、72 h后RPE细胞增生细胞核抗原（PCNA）的表达量和凋亡率。透射电子显微镜进行RPE细胞形态学检测。结果 姜黄素24、48、72、96 h的IC50分别是29.31、17.50、13.24、10.99 μg/ml。姜黄素使RPE细胞阻滞在G0/G1期。姜黄素15 μg/ml作用24、48、72 h后,RPE细胞的PCNA表达量分别为（565.04±23.60）,（473.61±36.88）,（396.15±32.45）,凋亡率分别为（12.83±0.13）%,（32.27±4.51）%,（56.81±8.67）%,各浓度组与对照组相比,差异均有统计学意义（P＜0.05）。透射电子显微镜显示RPE细胞出现凋亡特征。结论 姜黄素可以影响RPE细胞的PCNA合成,诱导其凋亡,从而有效抑制RPE细胞增生。姜黄素有望成为一种有效的防治PVR的天然药物。     

应用纳米技术研究p21cip1基因对人RPE增殖的抑制作用

目的:通过新兴的纳米粒子基因载体观察p21cip1基因对视网膜色素上皮(retinal pigment epithelium,RPE)细胞增殖的抑制情况。方法:制备p21cip1基因纳米粒子,将其转染到培养的人RPE细胞,通过免疫组织化学检测p21cip1蛋白的表达,流式细胞仪检测细胞周期的相关细胞量的变化。结果:p21cip1纳米粒子的DNA含量为3%,包封效率为78%,p21cip1基因在体内由于PLGA-PVA载体的保护作用,可以维持比质粒更长时间的有效期,减少质粒易被生物体内核酸酶降解的问题。流式细胞仪检测显示转染了目的基因的RPE细胞发生G1期阻滞,细胞增殖明显受到抑制。免疫组织化学检测结果显示转染了目的基因的RPE细胞p21cip1蛋白表达明显增强。结论:p21cip1基因有可能作为一个目的基因,借助新兴的基因载体纳米粒子用于抑制细胞增殖的基因治疗。     

miR-29b激活自噬抑制人视网膜色素上皮细胞增殖的实验研究

目的　研究miR-29b激活自噬抑制人视网膜色素上皮（retinal pigment epithelial，RPE）细胞增殖的作用。方法　通过病毒颗粒包装转染RPE细胞24~72 h，在倒置荧光显微镜下观察荧光强度检测感染效率，利用实时定量PCR检测miR-29b mRNA表达。采用凝血酶刺激RPE细胞增殖模拟增生性玻璃体视网膜病变模型。使用0.5×10³ U·L^-1凝血酶预刺激1 h，然后分别加入miR-29b和Lenti-vector空载体刺激24 h。分为空白对照组（Sham组）、凝血酶刺激组（RPE组）、凝血酶刺激组+miR-29b过表达组（RPE+Lenti-29b组）、凝血酶刺激组+空载体组（RPE+Lenti-vector组）。利用MTT微量酶比色法检测各组RPE细胞增殖情况，Western blot观察微管相关蛋白1轻链3（light chain 3,LC3）Ⅱ表达变化。结果　在倒置荧光显微镜下观察发现，RPE+Lenti-29b组和RPE+Lenti-vector组90%以上的RPE细胞成功转染，且RPE+Lenti-29b组miR-29 mRNA水平高表达，与其余3组相比差异均有统计学意义（均为P<0.01）。与Sham组比较，其余3组RPE细胞增殖明显，差异均有统计学意义（均为P<0.05），LC3Ⅱ蛋白表达也明显升高，差异均有统计学意义（均为P<0.05）；与RPE+Lenti-29b组比较，RPE组和RPE+Lenti-vector组细胞增殖明显（均为P<0.05），但LC3Ⅱ蛋白表达明显低于RPE+Lenti-29b组，差异有统计学意义（P<0.01）。结论　上调miR-29b表达可激活RPE细胞中LC3Ⅱ蛋白表达，提高细胞自噬水平，抑制RPE细胞增殖，可能在增生性玻璃体视网膜病变发生及发展中扮演重要作用。     

Antiproliferative Wirkung von Genistein auf kultivierte retinale Pigmentepithelzellen vom Schwein

The isoflavonoid genistein is known as a potent inhibitor of proliferation in endothelial cells and in some tumor cell lines in vitro and in vivo. Cell growth arrest is mediated by inhbitor of the tyrosine-kinase receptor, a target for many growth factors such as fibroblast growth factor, platelet-derived growth factor, epidermal growth-factor and vascular endothelial growth factor, which may play a role in the development of proliferative vitreoretinopathy (PVR). In this study we report on the antiproliferative effect of genistein on retinal pigment epithelial cells (RPE), which is the major cell type involved in PVR. METHODS: Cell culture experiments using porcine RPE treated with different concentrations (5 up to 100 microgram/ml) of genistein in minimum essential medium +10% fetal calf serum. Inhibition of proliferation was demonstrated by two different methods: (1) uptake of 5-bromo-2-deoxyuridin (BrdU) in S phase after different exposure times (2) expression of proliferating cell nuclear antigen 72 h after scratching confluent RPE. RESULTS: Exposure of RPE to genistein resulted in a concentration-dependent inhibition of cell proliferation at concentrations over 25 microgram/ml geinistein. BrdU incorporation was reduced to 65% after 24- and 48-hour treatment with 100 microgram/ml genistein in comparison with the untreated cells. Proliferation of RPE growing into the artificial wound was inhibited when cells were exposed for 72 h to more than 25 microgram/ml genistein. CONCLUSIONS: Genistein at concentrations over 25 microgram/ml inhibits RPE proliferation. Further studies will be required to determine the applicability of genistein or other phytoestrogens in order to prevent uncontrolled wound healing processes such as PVR.