蛋白磷酸酶1在D-半乳糖诱导老化小鼠耳蜗中的表达

The Role of PP1 in the Cochlea of Mimetic Aging Mice Induced by D-galactose

许涛;马婷婷;吴喜迪;刘双月;

1:锦州医科大学生命科学研究院

2:锦州医科大学生理学教研室

摘要
目的观察D-半乳糖诱导老化小鼠耳蜗中蛋白磷酸酶1(protein phosphatase 1,PP1)的定位表达及作用。方法 40只昆明小鼠随机分为对照组和D-半乳糖组,每组20只。D-半乳糖组颈背部皮下注射D-半乳糖(800mg·kg(-1)·d(-1)·d(-1)),对照组每日皮下注射等量生理盐水,连续给药8w;停药后检测血浆总超氧化物歧化酶(superoxide dismutase,SOD)活力和丙二醛(Malondialdehyde,MDA)水平;免疫荧光法定位PP1在耳蜗的表达,real-time PCR法检测耳蜗中PP1mRNA水平,Western blot法检测小鼠蛋白磷酸酶1核目标亚基(protein phosphates 1nuclear targeting subunit,PNUTS)、PP1及caspase-3的表达。结果与对照组比较,D-半乳糖组小鼠总SOD活力降低而MDA水平升高(均为P<0.01);PP1主要定位表达于小鼠耳蜗毛细胞、螺旋神经节细胞及血管纹细胞的胞核和胞浆中,且给予D-半乳糖后,小鼠耳蜗中PP1mRNA及其蛋白表达水平显著升高,而PNUTS表达减少,caspase-3表达增加(均为P<0.05)。结论 PP1在D-半乳糖诱导老化小鼠耳蜗毛细胞、螺旋神经节及血管纹细胞中表达,且参与了其耳蜗老化过程。
关键词
蛋白磷酸酶1;D-半乳糖;耳蜗;年龄相关性听力损失
基金项目(Foundation):
辽宁省教育厅(No.L2015316)资助
作者
许涛;马婷婷;吴喜迪;刘双月;
参考文献

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