Department of Ophthalmology, Kaohsiung Municipal Siaogang Hospital, Kaohsiung 812, Taiwan.
Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan.
Int J Mol Sci. 2021 Jan 29;22(3):1338. doi: 10.3390/ijms22031338.
Age-related macular degeneration (AMD) is the progressive degeneration of the retinal pigment epithelium (RPE), retina, and choriocapillaris among elderly individuals and is the leading cause of blindness worldwide. Thus, a better understanding of the underlying mechanisms in retinal tissue activated by blue light exposure is important for developing novel treatment and intervention strategies. In this study, blue-light-emitting diodes with a wavelength of 440 nm were applied to RPE cells at a dose of 3.7 ± 0.75 mW/cm for 24 h. ARPE-19 cells were used to investigate the underlying mechanism induced by blue light exposure. A trypan blue exclusion assay was used for the cell viability determination. Flow cytometry was used for apoptosis rate detection and autophagy analysis. An immunofluorescence microscopy analysis was used to investigate cellular oxidative stress and DNA damage using DCFDA fluorescence staining and an anti-γH2AX antibody. Blue light exposure of zebrafish larvae was established to investigate the effect on retinal tissue development in vivo. To further demonstrate the comprehensive effect of blue light on ARPE-19 cells, next-generation sequencing (NGS) was performed for an ingenuity pathway analysis (IPA) to reveal additional related mechanisms. The results showed that blue light exposure caused a decrease in cell proliferation and an increase in apoptosis in ARPE-19 cells in a time-dependent manner. Oxidative stress increased during the early stage of 2 h of exposure and activated DNA damage in ARPE-19 cells after 8 h. Furthermore, autophagy was activated in response to blue light exposure at 24-48 h. The zebrafish larvae model showed the unfavorable effect of blue light in prohibiting retinal tissue development. The RNA-Seq results confirmed that blue light induced cell death and participated in tissue growth inhibition and maturation. The current study reveals the mechanisms by which blue light induces cell death in a time-dependent manner. Moreover, both the in vivo and NGS data uncovered blue light's effect on retinal tissue development, suggesting that exposing children to blue light could be relatively dangerous. These results could benefit the development of preventive strategies utilizing herbal medicine-based treatments for eye diseases or degeneration in the future.
年龄相关性黄斑变性（AMD）是老年人视网膜色素上皮（RPE）、视网膜和脉络膜毛细血管的进行性退化，是全球致盲的主要原因。因此，更好地了解蓝光照射激活的视网膜组织中的潜在机制对于开发新的治疗和干预策略非常重要。在这项研究中，波长为 440nm 的蓝光发光二极管以 3.7±0.75mW/cm 的剂量照射 RPE 细胞 24 小时。使用 ARPE-19 细胞来研究蓝光照射诱导的潜在机制。使用台盼蓝排除试验来确定细胞活力。使用流式细胞术检测凋亡率和自噬分析。使用 DCFDA 荧光染色和抗 γH2AX 抗体的免疫荧光显微镜分析来研究细胞氧化应激和 DNA 损伤。建立斑马鱼幼虫的蓝光照射模型来研究体内对视网膜组织发育的影响。为了进一步证明蓝光对 ARPE-19 细胞的综合影响，进行了下一代测序（NGS）进行了Ingenuity Pathway Analysis（IPA），以揭示其他相关机制。结果表明，蓝光照射以时间依赖性方式导致 ARPE-19 细胞增殖减少和凋亡增加。暴露 2 小时时氧化应激增加，暴露 8 小时后 ARPE-19 细胞中的 DNA 损伤被激活。此外，自噬在暴露 24-48 小时后被蓝光激活。斑马鱼幼虫模型显示蓝光在抑制视网膜组织发育方面的不利影响。RNA-Seq 结果证实蓝光诱导细胞死亡，并参与组织生长抑制和成熟。本研究揭示了蓝光以时间依赖性方式诱导细胞死亡的机制。此外，体内和 NGS 数据均揭示了蓝光对视网膜组织发育的影响，这表明让儿童暴露在蓝光下可能相对危险。这些结果可能有助于未来利用草药为基础的治疗方法开发针对眼部疾病或变性的预防策略。
