目的探讨4-苯基丁酸钠(4-phenyl butyric acid,4-PBA)对缺氧复氧诱导心肌细胞内质网应激的影响。方法建立原代培养的心肌细胞缺氧复氧模型,随机将细胞分为对照组(Control组)、4-苯基丁酸钠预处理组(4-PBA组)、缺氧复氧组(H/R组)和4-苯基丁酸钠+缺氧复氧组(4-PBA+H/R组),应用CCK-8试剂盒检测细胞活力,caspase-3活性试剂盒测定caspase-3活性及Tunel染色测定凋亡细胞比率,western blot检测内质网应激标志性蛋白C/EBP同源蛋白(C/EBP homologous protein,CHOP)表达。结果与对照组[(100±5.31)%]比较,缺氧复氧组细胞活力[(77.45±5.67)%]显著降低(P〈0.01);而与H/R组比较,4-PBA+H/R组[(87.64±4.62)%]细胞活力明显升高(P〈0.05);H/R组caspase活性(1.86±0.14)较对照组(0.82±0.14)显著增加(P〈0.01),4-PBA预处理组(1.09±0.11)较H/R组相比明显降低(P〈0.05);H/R组Tunel阳性细胞比率[(37.55±3.51)%]较对照组[(6.78±1.75)%]相比显著升高(P〈0.01),而4-PBA+H/R组[(20.81±2.72)%]较H/R组相比显著降低(P〈0.01);H/R组CHOP表达(1.99±0.21)较对照组(0.98±0.14)显著上调(P〈0.01),而4-PBA预处理组CHOP表达(1.36±0.18)与H/R组相比明显降低(P〈0.05)。结论缺氧复氧能够诱导心肌细胞凋亡及内质网应激,而4-PBA能够减轻内质网应激及心肌细胞缺氧复氧损伤。
Objective This study was designed to explore the effect of 4-PBA on hypoxia/reoxygenation induced endoplasmic reticulum stress(ERS)in cardiomyocytes H/R injury.Methods Primary cultured cardiomyocyctes were exposure to H/R to stimulating I/R injury and randomly divided to control group(Control),4-PBA group(4-PBA),H/R group,4-PBA +H/R group(4-PBA +H/R).CCK-8assessed the cell viability of cardiomyocyctes,Caspase-3activity was measured and Tunel staining was performed to estimate the apoptotic cardiomyocytes.Western blot was used to assess the protein expression of CHOP.Results Compared to the control group[(100±5.31)% [],cell viability in H/R group[(77.45±5.67)%]was significantly decreased(P〈0.01).4-PBA pretreatment[(87.64±4.62)%]ameliorated,compared to the H/R group(P〈0.05).Caspase-3activity in H/R group(1.86±0.14)was obviously increased compared to that in the control group(0.82±0.14)(P〈0.01).4-PBA pretreatment decreased viability,compared to the H/R group(P〈0.05).Apoptotic index in H/R group[(37.55±3.51)%]was increased compared to that in the control group [(6.78±1.75)% ](P〈0.01).4-PBA pretreatment[(20.81±2.72)%]decreased the apoptotic index,compared to the H/R group(P〈0.01).Expression of CHOP in H/R group(1.99±0.21)was upregulated compared to the control group(0.98±0.14)(P〈0.01)and the upregulating of CHOP in H/R group was attenuated as compared to the 4-PBA+H/R group(1.36±0.18)(P〈0.05).Conclusion H/R exposure treatment could induce cardiomyocytes apoptosis and ERS,and 4-PBA pretreatment could effectively protect cardimyocytes against H/R injury via attenuating ERS and apoptotic cell death.