摘要目的:观察多聚嘧啶序列结合蛋白相关剪接因子（PSF）对缺氧诱导的人视网膜微血管内皮细胞（hRMECs）功能的影响。方法:采用三质粒系统构建慢病毒颗粒（LV）-PSF。LV-PSF体外感染hRMECs后通过流式细胞计数法测定其感染效率。应用实时定量PCR （RT-PCR）检测经LV-PSF感染的hRMECs中PSF mRNA表达水平。将实验分为体内和体外两部分。体内实验：7日龄健康C57B/L6小鼠20只，采用随机数字表法分为正常组、氧诱导视网膜病变（OIR）组、OIR+LV-空载体（Vec）组和OIR+LV-PSF组，每组5只。除正常组外，其余3组构建OIR模型。OIR组除缺氧刺激外，不做其余处理。OIR+LV-Vec组和OIR+LV-PSF组小鼠分别玻璃体腔注射LV-Vec或LV-PSF。观察LV-PSF对视网膜新生血管（RNV）形成的影响。体外实验：将hRMECs分为正常组、缺氧组、空载组、PSF高表达组。正常组为正常体外培养的hRMECs；缺氧组为缺氧刺激3 h恢复正常培养条件24 h的hRMECs；空载组、PSF高表达组分别为用LV-Vec、LV-PSF感染48 h，再用缺氧刺激3 h恢复正常培养条件24 h的hRMECs。采用MTT比色法观察PSF对细胞增生能力的影响。采用细胞划痕实验和Transwell迁移实验观察PSF对缺氧刺激下细胞迁移能力的影响。采用RT-PCR观察各组细胞中HIF-1α、VEGF及PSF的mRNA表达。结果:成功构建可稳定高表达PSF的LV-PSF，流式细胞仪测定其感染效率为97%，RT-PCR测得经LV-PSF感染的hRMECs中PSF mRNA水平明显上调。体内实验：OIR组、OIR+LV-Vec组小鼠RNV面积较正常组明显增加（ t=18.31、43.71），OIR+LV-PSF组小鼠RNV面积较OIR组（ t=11.30）、OIR+LV-Vec组（ t=15.47）明显减小，差异均有统计学意义（ P <0.05 ）。体外实验：MTT比色法检测结果显示，缺氧组hRMECs增生能力较正常组明显增强（ t=2.57），PSF高表达组hRMECs增生能力较正常组、缺氧组、空载组明显降低（ t=5.26、5.46、3.73 ），差异均有统计学意义（ P<0.05 ）。细胞划痕实验结果显示，缺氧刺激3 h恢复正常条件24 h或48 h均可刺激缺氧组与空载组细胞明显迁移（ t=8.35、13.84， P<0.05 ）；而与缺氧组与空载组比较，PSF高表达组细胞迁移不明显（ t=10.99、18.27、9.75、8.93、26.94、7.01 ， P <0.05）。Transwell小室实验结果显示，正常组和空载组微孔膜上染色的细胞数较多，而PSF高表达组微孔膜上染色的细胞数明显减少（ t=9.33、6.15， P<0.05）。RT-PCR检测结果显示，与正常组比较，缺氧组、空载组hRMECs中HIF-1α、VEGF的mRNA表达明显增加（ t=15.23、21.09， P<0.05），PSF mRNA表达无明显变化（ t=0.12、2.15， P<0.05 ）；与缺氧组、空载组比较，PSF高表达组hRMECs中HIF-1α、VEGF的mRNA表达明显下降（ t=10.18、13.10， P<0.05），PSF mRNA表达明显增加（ t=65.00、85.79， P<0.05 ）。 结论:PSF可减少OIR模型小鼠RNV面积。PSF可能通过HIF-1α/VEGF信号通路抑制缺氧诱导的hRMECs增生和迁移。

abstractsObjective:To observe the effect of pyrimidine bundle-binding protein-associated splicing factors (PSF) on the function of hypoxia-induced human retinal microvascular endothelial cells (hRMECs).Methods:A three-plasmid system was used to construct lentivirus (LV)-PSF. After LV-PSF infected hRMECs in vitro, the infection efficiency was measured by flow cytometry. Real-time quantitative PCR (RT-PCR) was used to detect the expression of PSF mRNA in hRMECs infected with LV-PSF. The experiment was divided into two parts, in vivo and in vitro. In vivo experiments: 20 healthy C57B/L6 mice at the age of postnatal 7 were randomly divided into normal group, oxygen-induced retinopathy (OIR) group, OIR+LV-Vec group, and OIR+LV-PSF group, each group has five mice. Mice in 3 groups were constructed with OIR models except the normal group and the mice in OIR group were not treated. The mice in the OIR + LV-Vec group and the OIR+LV-PSF group were injected with an empty vector (LV-Vec) or LV-PSF in the vitreous cavity, respectively. The effect of LV-PSF on the formation of retinal neovascularization (RNV) was observed then. In vitro experiments: hRMECs were divided into normal group, hypoxia group, vector group, and PSF high expression group. HRMECs in the normal group were cultured in vitro; hRMECs in the hypoxic group were restored to normal culture conditions for 3 h after 3 h of hypoxia stimulation; hRMECs in the vector group and PSF high expression group were infected with LV-Vec and LV-PSF for 48 h, and hRMECs were returned to normal culture conditions for 24 h with hypoxia stimulation for 3 h. The effect of PSF on cell proliferation was observed by MTT colorimetry. Cell scratch test and Transwell migration experiment were used to observe the effect of PSF on cell migration ability under hypoxia stimulation. RT-PCR was used to observe the mRNA expression of HIF-1α, VEGF and PSF in each group of cells.Results:The LV-PSF of stably expressing PSF was successfully constructed. The infection efficiency was 97% determined by flow cytometry. The level of PSF mRNA in hRMECs infected with LV-PSF was significantly increased and detected by RT-PCR. In vivo experiments: The RNV area of the mice in the OIR group and the OIR + LV-Vec group was significantly increased compared to the normal group ( t=18.31, 43.71), and the RNV area of the mice in the OIR + LV-PSF group was smaller than that in the OIR group ( t=11.30) and OIR + The LV-Vec group ( t=15.47), and the differences were statistically significant ( P<0.05). In vitro experiments: MTT colorimetry results showed that the proliferative capacity of hRMECs in the hypoxic group was significantly enhanced compared with the normal group ( t=2.57), and the proliferative capacity of hRMECs in the PSF high expression group was significantly lower than that of the normal, hypoxic, and vector groups ( t=5.26, 5.46, 3.73), the differences were statistically significant ( P<0.05). The results of cell scratch test showed that the hRMECs could be stimulated by the hypoxia stimulation for 3 hours to restore the normal condition for 24 hours or 48 hours ( t=8.35, 13.84; P<0.05). Compared with the vector group, cell migration rate in the PSF-high expression group was not significant ( t=10.99, 18.27, 9.75, 8.93, 26.94, 7.01; P<0.05). Transwell experiments showed that the number of cells stained on the microporous membrane was higher in the normal group and the vector groups, while the number of cells stained in the PSF high expression group was significantly reduced ( t=9.33, 6.15; P<0.05). The results of RT-PCR showed that the mRNA expression of HIF-1α and VEGF in hRMECs in the hypoxic and vector groups increased significantly compared with the normal group ( t=15.23, 21.09; P<0.05), but no change in the mRNA expression of PSF ( t=0.12, 2.15; P>0.05); compared with the hypoxia group and the vector group, the HIF-1α and VEGF mRNA expression in hRMECs in the PSF high expression group were significantly decreased ( t=10.18, 13.10; P<0.05), but the PSF mRNA expression increased ( t=65.00, 85.79; P<0.05). Conclusion:PSF can reduce the RNV area in OIR model mice. PSF may inhibit hypoxia-induced proliferation and migration of hRMECs through the HIF-1α/VEGF signaling pathway.