聚嘧啶束结合蛋白相关剪接因子高表达对糖基化终末产物诱导下视网膜色素上皮细胞损伤的保护作用

目的观察聚嘧啶束结合蛋白相关剪接因子(PSF)高表达对糖基化终末产物(AGEs)诱导下RPE细胞损伤的保护作用。方法将体外培养的人RPE细胞分为正常对照组(N组)、空白对照组(N+AGAGEs组)、空载体对照组(Vec+AGEs组)、PSF高表达组(PSF+AGEs组)。N组RPE细胞常规培养;N+AGEs组只做转染处理但不导入任何外源性基因的RPE细胞联合AGEs诱导;Vec+AGEs组、PSF+AGEs组利用转染试剂脂质体2000将pcDNA空载体或pcDNA-PSF真核表达质粒导入RPE细胞联合AGEs诱导。除N组以外,其余3组细胞进行相应的转染处理,24 h后应用150μg/ml的AGEs刺激72 h。采用HE染色和Hoechst 33258染色观察PSF高表达对RPE细胞凋亡相关形态改变的影响;通过ROS水平检测分析PSF高表达对AGEs诱导的RPE细胞ROS表达的影响;采用MTT比色法检测PSF高表达对RPE细胞生存力的影响;采用Western blot检测PSF不同作用时间及不同剂量对血红素氧合酶1(HO-1)表达的影响。结果HE染色和Hoechst 33258染色观察发现,N组细胞形态饱满,细胞核呈圆形,细胞质丰富,染色均一;N+AGEs组、Vec+AGEs组细胞体积缩小,嗜酸性染色增强,细胞核致密浓染、固缩甚至碎裂;PSF+AGEs组细胞形态尚饱满,细胞浆染色较均匀,细胞核染色均一。MTT比色法检测结果显示,PSF高表达可有效提高RPE细胞生存力,但该作用可被ZnPP有效拮抗,且差异有统计学意义(F=33.26,P<0.05)。DCFH-DA法检测结果显示,与N+AGEs组、Vec+AGEs组比较,PSF+AGEs组细胞中ROS产量下降,差异有统计学意义(F=11.94,P<0.05)。Western blot检测结果显示,PSF蛋白以时间、剂量依赖性的方式上调HO-1的表达水平。PSF蛋白作用24、48、72 h的HO-1相对表达水平较0 h明显升高,差异有统计学意义(F=164.91,P<0.05)。0.1、0.5、1.0、1.5、2.0μg PSF蛋白作用下的HO-1相对表达水平较0.0μg明显升高,差异有统计学意义(F=104.82,P<0.05)。结论PSF可能通过上调HO-1的表达而抑制ROS产生,从而对AGEs诱导下的RPE细胞损伤发挥保护作用。

Protective effect of polypyrimidine bundle-binding protein-related splicing factor on retinal pigment epithelial cell injury induced by advanced glycation end products

Objective To observe the protective effect of polypyrimidine bundle-binding protein related splicing factor(PSF)over-expression on RPE cell injury induced by advanced glycation end products(AGEs).Methods The human RPE cells cultured in vitro were divided into three groups:normal control group(N group),blank control group(N+AGEs group),empty vector control group(Vec+AGEs group),and PSF high expression group(PSF+AGEs group).RPE cells in N group were routinely cultured;RPE cells in N+AGEs group were only transfected but did not introduce any exogenous genes combined with AGEs induction;Vec+AGEs group and PSF+AGEs group were transfected with pcDNA The empty vector or pcDNA-PSF eukaryotic expression plasmid was introduced into RPE cells and induced by AGEs.Except the N group,the other 3 groups of cells were transfected accordingly,and were stimulated with 150μg/ml AGEs for 72 h after 24 h.HE staining and Hoechst 33258 staining were used to observe the effect of high PSF expression on the morphological changes of RPE cells;ROS level detection was used to analyze the effect of PSF high expression on the ROS expression of RPE cells induced by AGEs;MTT colorimetric method was used to detect the high PSF expression Effects on the viability of RPE cells;Western blot was used to detect the effects of different time and dose of PSF on the expression of heme oxygenase 1(HO-1).Results HE staining and Hoechst 33258 staining observation showed that the cells in group N were full in shape,the nucleus was round,the cytoplasm was rich,and the staining was uniform;the cells in N+AGEs group and Vec+AGEs group were reduced in size,the eosinophilic staining was enhanced,and the nucleus was densely densely stained.Pyrolysis and even fragmentation;the morphology of cells in the PSF+AGEs group was still full,the cytoplasm staining was more uniform,and the nucleus staining was uniform.The results of MTT colorimetry showed that high expression of PSF can effectively improve the viability of RPE cells,but this effect can be effectively antagonized by ZnPP,and the difference is statistically significant(F=33.26,P<0.05).DCFH-DA test results showed that compared with the N+AGEs group and Vec+AGEs group,the ROS production in PSF+AGEs group decreased,the difference was statistically significant(F=11.94,P<0.05).Western blot analysis showed that PSF protein upregulated HO-1 expression in a time-and dose-dependent manner.The relative expression level of HO-1 at 24,48,and 72 h after PSF protein was significantly higher than that at 0 h,and the difference was statistically significant(F=164.91,P<0.05).The relative expression level of HO-1 under the action of 0.1,0.5,1.0,1.5,and 2.0μg PSF protein was significantly higher than 0.0μg,and the difference was statistically significant(F=104.82,P<0.05).Conclusion PSF may inhibit the production of ROS by up-regulating the expression of HO-1,thus protecting the RPE cells induced by AGEs.