PRMT6通过抑制PTEN/β-catenin通路对脂多糖诱导的肺支气管上皮细胞损伤的影响

PRMT6 relieves lipopolysaccharide-induced lung bronchial epithelial cell injury by inhibiting the PTEN/β-catenin pathway

目的探究蛋白质精氨酸甲基转移酶6(PRMT6)对脂多糖(LPS)诱导的肺支气管上皮细胞损伤的作用及其可能的作用机制。方法体外培养人支气管上皮细胞系16HBE,qRT-PCR检测细胞PRMT6mRNA表达;Western blot检测细胞PRMT6、磷酸酶和张力蛋白同源酶(PTEN)、磷酸化β-连环蛋白(p-β-catenin)和β-连环蛋白(β-catenin)蛋白表达;CCK-8检测细胞活力;流式细胞术检测细胞凋亡和活性氧(ROS)产生;检测细胞培养上清液中白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、丙二醛(MDA)含量和超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)活性。结果LPS呈剂量依赖性抑制细胞中PRMT6mRNA和蛋白表达。与空白对照组相比,LPS组细胞中PRMT6 mRNA和蛋白表达、p-β-catenin/β-catenin蛋白表达明显降低(P<0.05),细胞活力、SOD活性明显降低(P<0.05),PTEN蛋白表达、细胞凋亡率及ROS、MDA、IL-1β、IL-6、TNF-α含量和LDH活性明显升高(P<0.05);与LPS组相比,LPS+过表达空白对照(oe-NC)组细胞各指标差异均无统计学意义(P>0.05);与LPS+oe-NC组相比,LPS+过表达PRMT6(oe-PRMT6)组细胞中PRMT6mRNA和蛋白表达、p-β-catenin/β-catenin蛋白表达明显升高(P<0.05),细胞活力、SOD活性明显升高(P<0.05),PTEN蛋白表达、细胞凋亡率和ROS、MDA、IL-1β、IL-6、TNF-α含量及LDH活性明显降低(P<0.05);与LPS+oePRMT6组相比,LPS+oe-PRMT6+过表达PTEN(oe-PTEN)组细胞中PRMT6表达差异无统计学意义(P>0.05),p-β-catenin/β-catenin蛋白表达明显降低(P<0.05),细胞活力、SOD活性明显降低(P<0.05),PTEN蛋白表达、细胞凋亡率及ROS、MDA、IL-1β、IL-6、TNF-α含量和LDH活性明显升高(P<0.05)。结论PRMT6通过抑制PTEN/β-catenin通路改善LPS诱导的肺支气管上皮细胞损伤。

Objective To explore the effect of protein arginine methyltransferase 6(PRMT6)on lipopolysaccharide(LPS)-induced lung bronchial epithelial cell injury and its possible mechanism.Methods Human bronchial epithelial cell line 16HBE was cultured in vitro,and the expression of PRMT6 mRNA was detected by qRT-PCR.The expression of PRMT6,phosphatase and tensin homolog(PTEN),p-β-catenin andβ-catenin was detected by Western blot.Cell viability was detected by CCK-8.Cell apoptosis and ROS production were detected by flow cytometry.The contents of interleukin(IL)-1β,IL-6,tumor necrosis factor(TNF)-αand malondialdehyde(MDA),as well as SOD and lactate dehydrogenase(LDH)activities in the supernatant of cell culture was detected.Results LPS inhibited the expression of PRMT6 mRNA and protein in cells in a dose-dependent manner.Compared with the blank control group,the LPS group showed significantly decreases in the expression of PRMT6 mRNA and protein,the expression of p-β-catenin/β-catenin protein(P<0.05),decreases in cell viability and SOD activity(P<0.05),and increases in the expression of PTEN protein,apoptosis rate,the contents of ROS,MDA,IL-1β,IL-6 and TNF-α,and LDH activity(P<0.05).Compared with the LPS group,there was no statistically significant differences in the indicators of the LPS+oe-NC group(P>0.05).Compared with the LPS+oe-NC group,the LPS+oe-PRMT6 group presented remarkable increases in the expression of PRMT6 mRNA and protein,the expression of p-β-catenin/β-catenin protein(P<0.05),increases in cell viability and SOD activity(P<0.05),and decreases in the expression of PTEN protein,apoptosis rate,the contents of ROS,MDA,IL-1β,IL-6 and TNF-α,and LDH activity(P<0.05).Compared with the LPS+oe-PRMT6 group,the LPS+oe-PRMT6+oe-PTEN group showed the expression of PRMT6 without significant difference(P>0.05),remarkable decreases in the expression of p-β-catenin/β-catenin protein(P<0.05),decreases in cell viability and SOD activity(P<0.05),and increases in the expression of PTEN protein,apoptosis rate,the contents of ROS,MDA,IL-1β,IL-6 and TNF-α,and LDH activity(P<0.05).Conclusions PRMT6 can improve lung bronchial epithelial cell injury induced by LPS by inhibiting the PTEN/β-catenin pathway.