Elner Susan G, Elner Victor M, Field Matthew G, Park Seung, Heckenlively John R, Petty Howard R
Department of Ophthalmology, University of Michigan, Ann Arbor, USA.
Trans Am Ophthalmol Soc. 2008;106:215-22; discussion 222-4.
To establish that increased autofluorescence of mitochondrial flavoproteins, an indicator of mitochondrial oxidative stress, correlates with retinal cell dysfunction.
Retinal flavoprotein autofluorescence (FA) was imaged in humans with a fundus camera modified with 467DF8-nm excitation and 535-nm emission filters and a back-illuminated, electron-multiplying, charge-coupled device camera interfaced with a computer equipped with customized image capture software. Multiple digital images, centered on the fovea, were obtained from each eye. Histograms of pixel intensities in grayscale units were analyzed for average intensity and average curve width. Adults with diabetes mellitus, age-related macular degeneration (ARMD), central serous retinopathy, and retinal dystrophies, as well as healthy control volunteers, were imaged. Monolayers of cultured human retinal pigment epithelial (HRPE) cells, HRPE cells exposed to sublethal doses of H2O2, and HRPE cells exposed to H2O2 in the presence of antioxidants were imaged for FA using fluorescent photomicroscopy.
Control patients demonstrated low levels of retinal FA, which increased progressively with age. Diabetics without visible retinopathy demonstrated increased FA levels compared to control volunteers (P < .001). Diabetics with retinopathy demonstrated significantly higher FA values than those without retinopathy (P < .04). Patients with ARMD, central serous retinopathy, or retinal dystrophies also demonstrated significantly increased FA. Compared to control RPE cells, cells oxidatively stressed with H2O2 had significantly elevated FA (P < .05), which was prevented by antioxidants (P < .05).
Retinal FA is significantly increased with age and diseases known to be mediated by oxidative stress. Retinal FA imaging may provide a novel, noninvasive method of assessing retinal health and retinal dysfunction prior to retinal cell death.
证实线粒体黄素蛋白自身荧光增加（线粒体氧化应激的一个指标）与视网膜细胞功能障碍相关。
使用配备467DF8纳米激发滤光片和535纳米发射滤光片的眼底相机以及与装有定制图像采集软件的计算机相连的背照式电子倍增电荷耦合器件相机，对人类视网膜黄素蛋白自身荧光（FA）进行成像。从每只眼睛获取以黄斑为中心的多个数字图像。分析灰度单位像素强度的直方图以获取平均强度和平均曲线宽度。对患有糖尿病、年龄相关性黄斑变性（ARMD）、中心性浆液性视网膜病变和视网膜营养不良的成年人以及健康对照志愿者进行成像。使用荧光显微镜对培养的人视网膜色素上皮（HRPE）细胞单层、暴露于亚致死剂量过氧化氢的HRPE细胞以及在抗氧化剂存在下暴露于过氧化氢的HRPE细胞进行FA成像。
对照患者的视网膜FA水平较低，且随年龄逐渐增加。与对照志愿者相比，无可见视网膜病变的糖尿病患者FA水平升高（P < 0.001）。患有视网膜病变的糖尿病患者的FA值明显高于无视网膜病变的患者（P < 0.04）。患有ARMD、中心性浆液性视网膜病变或视网膜营养不良的患者的FA也明显增加。与对照RPE细胞相比，用过氧化氢进行氧化应激处理的细胞FA显著升高（P < 0.05），而抗氧化剂可预防这种升高（P < 0.05）。
视网膜FA随年龄以及已知由氧化应激介导的疾病显著增加。视网膜FA成像可能提供一种在视网膜细胞死亡之前评估视网膜健康和视网膜功能障碍的新型非侵入性方法。
