miRNA-370沉默对酒精性肝病大鼠的保护作用及机制研究

目的:探究微小RNA（miRNA）-370沉默对酒精性肝病（ALD）大鼠的作用及机制。方法:32只Sprague-Dawley（SD）大鼠随机分为4组:正常组（普通饲料）、模型组（40%酒精灌胃+隔日高脂饲料饲养）、空载组（40%酒精灌胃+隔日高脂饲料饲养+尾静脉注射含空载质粒的腺病毒）和沉默组（40%酒精灌胃+隔日高脂饲料饲养+尾静脉注射含si-miRNA-370质粒的腺病毒），每组各8只。用40%酒精灌胃联合隔日高脂饲料饲养法构建ALD大鼠模型。酶联免疫吸附法检测超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和丙二醛（MDA）表达水平；实时荧光定量PCR法检测miRNA-370、沉默信息调节因子6（SIRT6）mRNA和Nrf2 mRNA表达水平；蛋白质免疫印迹法检测SIRT6和Nrf2表达水平。结果:与正常组比较，模型组SOD、GSH-Px、SIRT6 mRNA、Nrf2 mRNA、SIRT6和Nrf2水平降低，丙氨酸氨基转移酶（ALT）、天门冬氨酸氨基转移酶（AST）、甘油三酯（TG）、MDA和miRNA-370水平升高，差异均有统计学意义（q=10.306、14.839、9.040、10.645、5.836、8.775、11.098、10.066、8.569、4.976、12.435，均P＜0.05）。与空载组比较，沉默组SOD、GSH-Px、SIRT6 mRNA、Nrf2 mRNA、SIRT6和Nrf2水平升高，ALT、AST、TG和miRNA-370水平降低，差异均有统计学意义（q=5.731、9.537、14.524、29.569、8.888、16.233、8.144、6.818、5.329、21.317，均P＜0.05）。结论:MiRNA-370沉默可改善ALD大鼠肝脏损伤，升高SOD和GSH-Px水平，其机制可能与调控SIRT6和Nrf2表达有关。

Study on the protective effect and mechanism of microRNA-370 silencing on rats with alcoholic liver disease

Objective: To explore the effect and mechanism of microRNA（miRNA）-370 silencing on rats with alcoholic liver disease （ALD）. Methods:Thirty-two Sprague-Dawley（SD）rats were randomly divided into 4 groups: normal group （common feed），model group （40% alcohol gavage + high-fat feed feeding every other day），no-load group（40% alcohol gavage + high-fat feed feeding every other day + tail vein injection of adenovirus containing empty plasmid） and silent group（40% alcohol gavage + high-fat feed feeding every other day + tail vein injection of adenovirus containing si-miRNA-370 plasmid），8 rats in each group. An ALD rat model was constructed using 40% alcohol gavage combined with high-fat feed every other day. Enzyme-linked immunosorbent assay was used to detect the expression levels of superoxide dismutase （SOD），glutathione peroxidase（GSH-Px） and malondialdehyde（MDA）. Real-time fluorescence quantitative PCR method was used to detect miRNA-370 and SIRT6 mRNA and Nrf2 mRNA expression levels. Western blotting was used to detect the expression levels of SIRT6 and Nrf2. Results:Compared with the normal group，the levels of SOD，GSH-Px，SIRT6 mRNA，Nrf2 mRNA，SIRT6 and Nrf2 in the model group were decreased，and the levels of alanine aminotransferase（ALT），aspartate aminotransferase（AST），triglyceride（TG），MDA and miRNA-370 were increased，the differences were statistically significant （q=10.306， 14.839，9.040，10.645，5.836，8.775，11.098，10.066，8.569，4.976，12.435，all P<0.05）. Compared with the no-load group，the levels of SOD，GSH-Px，SIRT6 mRNA，Nrf2 mRNA，SIRT6，and Nrf2 in the silent group increased，while the levels of ALT，AST，TG and miRNA-370 decreased，the differences were statistically significant （q=5.731，9.537，14.524，29.569，8.888，16.233，8.144，6.818，5.329，