核因子κB和白细胞介素-6在放射性膀胱损伤中的表达及意义

Expression and significance of nuclear factor-κB and interleukin-6 in radiation-induced bladder injury

目的检测核因子κB(NF-κB)和白细胞介素-6(IL-6)在放射性膀胱损伤中的表达特征及其相关性。方法选择人输尿管上皮永生化细胞SV-HUC-1进行培养,分别应用5、10和15 Gy的X线照射24、48和72 h,将未行照射的SV-HUC-1细胞作为正常对照组。CCK-8检测细胞增殖活性,实时定量PCR检测NF-κB和IL-6 mRNA的表达。将siRNA-NF-κB质粒转染至15 Gy X线照射72 h后的细胞株建立siRNA-NF-κB组(si-NF-κB组),将未转染质粒的15 Gy X线照射72 h后细胞株作为空白对照组,Western blotting检测IL-6蛋白的表达。将20只雄性SD大鼠分为模型组(一次性给予20 Gy X线照射,建立放射性膀胱损伤大鼠模型)和对照组(不给予照射),每组10只,2周后处死大鼠,实时定量PCR检测膀胱组织中NF-κB和IL-6 mRNA的表达。结果SV-HUC-1细胞中,细胞增殖活性随着照射剂量和照射时间的增加而降低,NF-κB和IL-6 mRNA的表达随着照射剂量和照射时间的增加而增加。si-NF-κB组中IL-6的表达量明显低于空白对照组(P<0.05)。放射性膀胱损伤大鼠模型的膀胱病变组织中,NF-κB和IL-6 mRNA的表达明显高于对照组(P<0.05),NF-κB和IL-6 mRNA的表达呈正相关。结论X线对膀胱的损伤呈浓度和时间依赖性,病变组织中NF-κB和IL-6的表达升高,二者具有协同作用。

Objective To detect the expression of nuclear factor-κB(NF-κB)and interleukin-6(IL-6)in radiation-induced bladder injury and analyze their relationship.Methods SV-HUC-1 cells were cultured and irradiated with X-ray doses of 5,10,and 15 Gy for 24,48,and 72 h,respectively,and those not irradiated were used as a normal control group.Proliferative activity of SV-HUC-1 cells was detected using a CCK-8 assay,and the expression of NF-κB and IL-6 mRNA was detected by real-time quantitative PCR.An siRNA-NF-κB plasmid was transfected into SV-HUC-1 cells following irradiation with 15 Gy for 72 h to establish the si-NF-κB group,and cells not transfected following irradiation with 15 Gy for 72 h was used as a blank control group.Expression of IL-6 protein was detected by Western blotting.Twenty male SD rats were divided into a model group(receiving 20 Gy irradiation to establish a model of radiation-induced bladder injury)and control group(n=10 per group).The expression of NF-κB and IL-6 mRNA in the rat urinary bladder tissues was detected by real-time quantitative PCR.Results With an increase in irradiation dose and time,the proliferative activity of SV-HUC-1 cells decreased,and the expression of NF-κB and IL-6 mRNA increased.The expression of IL-6 was significantly lower in the si-NF-κB group than in blank control group.The expression of NF-κB and IL-6 mRNA in the rat urinary bladder tissues was higher in the model group than in control group,and a positive correlation was observed between the expression of NF-κB and IL-6 mRNA.Conclusion Damage caused by X-rays to the urinary bladder is concentration-and time-dependent.High expression and synergistic effect of NF-κB and IL-6 lead to the formation of radiation-induced bladder injury.