Han Shuang, Kong Yi-Chun, Sun Bei, Han Quan-Hong, Chen Ying, Wang Yu-Chuan
Department of General Ophthalmology, Tianjin Eye Hospital, Tianjin Eye Institute, Tianjin Key Laboratory of Ophthalmology and Visual Science, Tianjin 300020, China.
Chin Med J (Engl). 2016 Mar 20;129(6):709-15. doi: 10.4103/0366-6999.178013.
The mechanisms of pathological retinal neovascularization (RNV) remain unknown. Several microRNAs were reported to be involved in the process of RNV. Oxygen-induced retinopathy (OIR) is a useful model to investigate RNV. Our present work explored the expression and the role of microRNA-128 (miR-218) in oxygen-induced RNV.
OIR was used to establish RNV model. The expression level of miR-218 in the retina from OIR mice was assessed by quantitative real-time reverse transcriptase polymerase chain reaction. Fluorescein angiography was performed in retinae of OIR mice, and RNV was quantified by hematoxylin and eosin staining to evaluate the effect of pCDH-CMV-miR-218 intravitreal injection on RNV in OIR mice. Roundabout 1 (Robo1) expression was detected by Western blotting in mouse retinal vascular endothelial cells expressing a high or low level of miR-218 and retinal tissues from OIR mice. Cell migration was evaluated by scratch wound assay.
In OIR mice, the expression level of miR-218 was significantly down-regulated (P = 0.006). Retinal Robo1 expression was significantly increased at both mRNA and protein levels (P = 0.001, 0.008; respectively). miR-218 intravitreal injection inhibited retinal angiogenesis in OIR mice, and the restoration of miR-218 in retina led to down-regulation of Robo1.
Our experiments showed that restoration of miR-218 inhibited retinal angiogenesis via targeting Robo1. MiR-218 contributed to the inhibition of retinal angiogenesis and miR-218 might be a new therapeutic target for preventing RNV.
病理性视网膜新生血管形成（RNV）的机制尚不清楚。据报道，几种微小RNA参与了RNV的过程。氧诱导性视网膜病变（OIR）是研究RNV的一种有用模型。我们目前的工作探讨了微小RNA-128（miR-218）在氧诱导的RNV中的表达及作用。
采用OIR建立RNV模型。通过定量实时逆转录聚合酶链反应评估OIR小鼠视网膜中miR-218的表达水平。对OIR小鼠的视网膜进行荧光素血管造影，并通过苏木精和伊红染色对RNV进行定量，以评估玻璃体腔内注射pCDH-CMV-miR-218对OIR小鼠RNV的影响。通过蛋白质印迹法检测高表达或低表达miR-218的小鼠视网膜血管内皮细胞及OIR小鼠视网膜组织中Roundabout 1（Robo1）的表达。通过划痕试验评估细胞迁移。
在OIR小鼠中，miR-218的表达水平显著下调（P = 0.006）。视网膜Robo1在mRNA和蛋白质水平均显著增加（分别为P = 0.001和0.008）。玻璃体腔内注射miR-218可抑制OIR小鼠的视网膜血管生成，视网膜中miR-218的恢复导致Robo1表达下调。
我们的实验表明，miR-218的恢复通过靶向Robo1抑制视网膜血管生成。MiR-218有助于抑制视网膜血管生成，且miR-218可能是预防RNV的新治疗靶点。
