Benedetto María M, Malcolm Melisa, Bruera Manuel G, Penazzi Laura G, Guido Mario E, Contín María A, Garbarino-Pico Eduardo
Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Biológica Ranwel Caputto. Córdoba, Argentina.
CONICET. Universidad Nacional de Córdoba. Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), Córdoba, Argentina.
Invest Ophthalmol Vis Sci. 2025 Jan 2;66(1):38. doi: 10.1167/iovs.66.1.38.
Stress granules (SGs) are cytoplasmic biocondensates formed in response to various cellular stressors, contributing to cell survival. Although implicated in diverse pathologies, their role in retinal degeneration (RD) remains unclear. We aimed to investigate SG formation in the retina and its induction by excessive LED light in an RD model.
Rat retinas were immunohistochemically analyzed for SG markers G3BP1 and eIF3, and SGs were also visualized by RNA fluorescence in situ hybridization. Additionally, SGs were induced in primary retinal cell and eyeball cultures using sodium arsenite. Light exposure experiments used LED lamps with a color temperature of 5500 K and 200 lux intensity for short-term or two- to eight-day exposures.
SGs were predominantly detected in retinal ganglion cells (RGCs) and inner nuclear layer (INL) cells, with arsenite-induction verified in RGCs. SG abundance was higher in animals exposed to light for 2-8 days compared to light/dark cycle controls. RGCs consistently exhibited more SGs than INL cells, and INL cells more than outer nuclear layer (ONL) cells (Scheirer-Ray-Hare test: H = 13.2, P = 0.0103 for light condition, and H = 278.2, P < 0.00001 for retinal layer). These observations were consistent across four independent experiments, each with three animals per light condition.
This study characterizes SGs in the mammalian retina for the first time, with increased prevalence after excessive LED light exposure. RGCs and INL cells showed heightened SG formation, suggesting a potential protective mechanism against photodamage. Further investigations are warranted to elucidate the role of SGs in shielding against light stress and their implications in retinopathies.
应激颗粒（SGs）是细胞在应对各种应激源时形成的细胞质生物凝聚物，有助于细胞存活。尽管其与多种病理状况有关，但其在视网膜变性（RD）中的作用仍不清楚。我们旨在研究视网膜中SGs的形成及其在RD模型中由过量LED光诱导的情况。
对大鼠视网膜进行免疫组织化学分析，检测SG标记物G3BP1和eIF3，同时通过RNA荧光原位杂交观察SGs。此外，使用亚砷酸钠在原代视网膜细胞和眼球培养物中诱导SGs。光照实验使用色温为5500K、强度为200勒克斯的LED灯进行短期或2至8天的照射。
SGs主要在视网膜神经节细胞（RGCs）和内核层（INL）细胞中检测到，亚砷酸钠诱导RGCs产生SGs得到证实。与光/暗循环对照组相比，暴露于光照2至8天的动物中SGs丰度更高。RGCs中的SGs始终比INL细胞更多，而INL细胞中的SGs比外核层（ONL）细胞更多（Scheirer-Ray-Hare检验：光照条件下H = 13.2，P = 0.0103；视网膜层条件下H = 278.2，P < 0.00001）。这些观察结果在四个独立实验中一致，每个光照条件下每组有三只动物。
本研究首次对哺乳动物视网膜中的SGs进行了表征，过量LED光照后其发生率增加。RGCs和INL细胞显示出SGs形成增加，表明存在针对光损伤的潜在保护机制。有必要进一步研究以阐明SGs在抵御光应激中的作用及其在视网膜病变中的意义。
