Chk2在Bmi1缺失所致的肾脏早衰和纤维化中的作用和机制研究  

Effect of Chk2 on Bmi1 Deficiency-induced Premature Renal Failure and Fibrosis

作　　者：陆劲红 王晶 杨翠翠 王婵 孙伟伟 苗登顺[1] LU Jin-hong;WANG Jing;YANG Cui-cui;WANG Chan;SUN Wei-wei;MIAO Deng-shun(Department of Anatomy,Histology and Embryology,Nanjing Medical University,Nanjing,Jiangsu,211100,China)

机构地区：[1]南京医科大学基础医学院人体解剖与组织胚胎学系骨与干细胞研究中心,江苏南京211100

出　　处：《现代生物医学进展》2023年第16期3001-3007,3020,共8页Progress in Modern Biomedicine

基　　金：国家自然科学基金重点项目(81730066);江苏省研究生创新计划项目(KYCX20_1381)。

摘　　要：目的:探究细胞周期检测点激酶2(cell-cycle checkpoint kinase 2,Chk2)在B淋巴瘤Mo-MLV插入区1(B cell-specific MLV integration site-1,Bmi1)缺失所致的肾脏早衰和纤维化中的作用及可能的机制。方法:取5周龄WT、Bmi1^(-/-)、Chk2^(-/-)、Bmi1^(-/-)Chk2^(-/-)小鼠肾脏,采用HE染色观察肾脏结构变化,采用免疫荧光和Masson染色观察肾脏纤维化情况,采用衰老相关β半乳糖苷酶(Senescence-associatedβ-galactosidase,SA-β-gal)染色观察肾脏衰老情况,采用免疫组化染色和western blot观察肾脏超氧化物歧化酶1(Superoxide Dismutase 1,SOD1)、超氧化物歧化酶2(Superoxide Dismutase 2,SOD2)表达水平和定位。从5周龄WT、Bmi1^(-/-)、Chk2^(-/-)、Bmi1^(-/-)Chk2^(-/-)小鼠肾脏皮质中提取和分离原代肾小管上皮细胞,采用免疫荧光和western blot检测其SOD1、SOD2表达水平。结果:与WT小鼠肾脏组织相比,Bmi1^(-/-)小鼠肾脏组织表现为体积变小、肾脏皮质厚度减少、肾小球数量减少,β-gal活性增加,SOD1和SOD2水平降低;与Bmi1^(-/-)小鼠肾脏相比,Bmi1^(-/-)Chk2^(-/-)小鼠肾脏体积增大、肾脏皮质厚度增加,肾小球数量增多,β-gal活性降低,SOD1和SOD2水平增加。与WT小鼠肾脏皮质原代肾小管上皮细胞相比,Bmi1^(-/-)小鼠肾脏皮质原代肾小管上皮细胞中SOD1和SOD2水平;与Bmi1^(-/-)小鼠肾脏皮质原代肾小管上皮细胞相比,Bmi1^(-/-)Chk2^(-/-)小鼠肾脏皮质原代肾小管上皮细胞中抗氧化指标SOD1和SOD2增加。结论:Chk2通过抑制肾小管上皮细胞的抗氧化能力促进Bmi1缺失所致的肾脏早衰和纤维化。Objective:To investigate the effect and possible mechanism of cell-cycle checkpoint kinase 2(Chk2)on premature renal aging and fibrosis caused by B cell-specific MLV integration site-1(Bmi1)deletion.Methods:5-week-old WT,Bmi1^(-/-),Chk2^(-/-),Bmi1^(-/-)Chk2^(-/-)mouse kidneys were taken,and the structural changes of the kidney were observed by HE staining,renal fibrosis was observed by immunofluorescence and Masson staining,renal aging by Senescence-associatedβ-galactosidase(SA-β-gal)staining,and the expression level and localization of renal Superoxide Dismutase 1(SOD1)and Superoxide Dismutase 2(SOD2)were observed by immunohistochemical staining and western blot.Primary tubular epithelial cells were extracted and isolated from the renal cortex of5-week-old WT,Bmi1^(-/-),Chk2^(-/-),and Bmi1^(-/-)Chk2^(-/-),and the expression levels of SOD1 and SOD2 were tested by immunofluorescence and western blot.Results:Compared with WT mouse kidney tissue,Bmi1^(-/-)mouse kidney tissue showed smaller volume,decreased renal cortex thickness,decreased glomerular number,increasedβ-gal activity,and decreased levels of SOD1 and SOD2.Compared with Bmi1^(-/-)mouse kidneys,Bmi1^(-/-)Chk2^(-/-)mice had an increase in kidney size,renal cortical thickness,glomerular number,decreasedβ-gal activity,and increased levels of SOD1 and SOD2.Compared with WT mouse renal cortical primary tubular epithelial cells,the levels of SOD1 and SOD2 in Bmi1^(-/-)mouse renal cortical primary tubular epithelial cells were reduced.Compared with Bmi1^(-/-)mouse renal cortical primary tubular epithelial cells,the levels of SOD1 and SOD2 were increased in Bmi1^(-/-)Chk2^(-/-)mouse kidney cortical primary tubular epithelial cells.Conclusions:Chk2 improves premature renal aging and fibrosis due to Bmi1 deficiency by inhibiting antioxidant capacity of tubular epithelial cells.

关 键 词：BMI1 CHK2 肾脏早衰 肾纤维化 抗氧化 

分 类 号：Q38[生物学—遗传学] Q591.2[医药卫生—人体解剖和组织胚胎学] R322.61[医药卫生—基础医学]