Ding Yi, Aredo Bogale, Zhong Xin, Zhao Cynthia X, Ufret-Vincenty Rafael L
Department of Ophthalmology, UT Southwestern Medical Center, Dallas, TX, 75390-9057, USA.
Department of Ophthalmology, UT Southwestern Medical Center, Dallas, TX, 75390-9057, USA.
Exp Eye Res. 2017 Jun;159:58-68. doi: 10.1016/j.exer.2017.03.009. Epub 2017 Mar 20.
Oxidative stress is an important contributor to the pathogenesis of many retinal diseases including age-related macular degeneration and retinal dystrophies. Light-induced retinal degeneration (LIRD) can serve as a model in which to study the response of the retina to stress. Of note, many genetic mutant mice are in a C57BL/6 J background and are thus resistant to the usual LIRD models. We recently developed a new model of fundus camera-delivered light-induced retinal degeneration (FCD-LIRD) which is effective in strains of mice expressing the light-resistant variant of RPE65 (450Met), including C57BL/6 J. In this work we investigated whether FCD-LIRD would be useful as a model in which to test the effect of genetic mutations on the response of the retina to stress. Furthermore, we tested whether oxidative stress plays an important role in the setting of this new FCD-LIRD model. FCD-LIRD was applied to C57BL/6 J mice and to mice simultaneously deficient in three proteins that are important in the response of the retina to oxidative stress (SOD1, DJ-1 and Parkin). Using fundus photography, we found that retinal damage was dramatically increased in the SOD1/DJ-1/Parkin deficient mice compared to C57BL/6 J. Outer retinal OCT volume and RPE cell morphology analysis in ZO-1-stained flat mounts added support to these findings. Gene expression analysis confirmed a strong oxidative stress response after FCD-LIRD, which was differentially altered in the SOD1/DJ1/Parkin deficient mice. We conclude that FCD-LIRD is useful to study the effect of genetic mutations on the response of the retina to light stress in light-resistant strains of mice. Furthermore, oxidative stress seems to be an important component of FCD-LIRD. Finally, we have established protocols to quantify the effect of FCD-LIRD on the retina and RPE which will be useful for future studies. Further dissection of the mechanisms by which the retina responds to light-induced oxidative stress may result in new strategies to modulate this response, which could lead to a reduction in retinal and RPE damage.
氧化应激是包括年龄相关性黄斑变性和视网膜营养不良在内的许多视网膜疾病发病机制的重要促成因素。光诱导性视网膜变性（LIRD）可作为研究视网膜对应激反应的模型。值得注意的是，许多基因敲除小鼠处于C57BL/6 J背景，因此对常用的LIRD模型具有抗性。我们最近开发了一种新的眼底相机递送光诱导性视网膜变性（FCD-LIRD）模型，该模型对表达RPE65（450Met）光抗性变体的小鼠品系有效，包括C57BL/6 J。在这项研究中，我们调查了FCD-LIRD是否可作为测试基因突变对视网膜对应激反应影响的模型。此外，我们测试了氧化应激在这种新的FCD-LIRD模型中是否起重要作用。将FCD-LIRD应用于C57BL/6 J小鼠以及同时缺乏三种对视网膜氧化应激反应重要的蛋白质（SOD1、DJ-1和Parkin）的小鼠。通过眼底摄影，我们发现与C57BL/6 J相比，SOD1/DJ-1/Parkin基因敲除小鼠的视网膜损伤显著增加。在ZO-1染色的平铺标本中进行的外层视网膜OCT体积和RPE细胞形态分析支持了这些发现。基因表达分析证实FCD-LIRD后有强烈的氧化应激反应，在SOD1/DJ1/Parkin基因敲除小鼠中该反应有差异地改变。我们得出结论，FCD-LIRD有助于研究基因突变对光抗性小鼠品系视网膜对光应激反应的影响。此外，氧化应激似乎是FCD-LIRD的重要组成部分。最后，我们建立了量化FCD-LIRD对视网膜和RPE影响的方案，这将对未来的研究有用。进一步剖析视网膜对光诱导氧化应激反应机制可能会产生调节这种反应的新策略，从而减少视网膜和RPE损伤。
