CAJ | 학술논문

采用C57BL6小鼠作为模型,SO2(7mg/m3)动式吸入染毒28d,每天染毒6h；SO2熏气开始后的第1~5d,腹腔注射BaP(40mg/kg b.w.),一天一次.吸入染毒结束后,采用分光光度计法检测小鼠肺线粒体膜电位(MMP)以及细胞色素C氧化酶(COX)的活性；采用荧光定量PCR技术,检测肺细胞中细胞色素C氧化酶亚基CO4以及核转录因子PGC1-α、NRF1、mtTFA的mRNA水平；并采用Western blot技术检测上述三种线粒体调控基因的蛋白表达.结果发现,在SO2和BaP复合暴露后,小鼠肺线粒体膜电位下降,氧化磷酸化复合体COX活性和亚基CO4的mRNA表达水平显著降低,调控基因NRF1和mtTFA的mRNA和蛋白水平也显著下调.提示小鼠在SO2和BaP复合暴露后,可能通过降低肺中NRF1表达,影响其对mtTFA的调控,进一步抑制相关基因组的转录和翻译,最终可能导致小鼠肺线粒体的氧化磷酸化功能受损,线粒体膜电位下降进而引发肺部疾病.
채용C57BL6소서작위모형,SO2(7mg/m3)동식흡입염독28d,매천염독6h；SO2훈기개시후적제1~5d,복강주사BaP(40mg/kg b.w.),일천일차.흡입염독결속후,채용분광광도계법검측소서폐선립체막전위(MMP)이급세포색소C양화매(COX)적활성；채용형광정량PCR기술,검측폐세포중세포색소C양화매아기CO4이급핵전록인자PGC1-α、NRF1、mtTFA적mRNA수평；병채용Western blot기술검측상술삼충선립체조공기인적단백표체.결과발현,재SO2화BaP복합폭로후,소서폐선립체막전위하강,양화린산화복합체COX활성화아기CO4적mRNA표체수평현저강저,조공기인NRF1화mtTFA적mRNA화단백수평야현저하조.제시소서재SO2화BaP복합폭로후,가능통과강저폐중NRF1표체,영향기대mtTFA적조공,진일보억제상관기인조적전록화번역,최종가능도치소서폐선립체적양화린산화공능수손,선립체막전위하강진이인발폐부질병.
C57BL6 male mice were exposed to SO2 (7mg/m3) for 28days, 6hours per day. In the first 5days of SO2 inhalation, mice were injected intraperitoneally with BaP (40mg/kg b. w.), which was dissolved in oil. The mitochondrial membrane potential (MMP) and activity of cytochrome C oxidase (COX) were detected by spectrophotometer. The mRNA levels of one subunit of COX (CO4) and three mitochondrial transcript factors (PGC1-α, NRF1, mtTFA) were analyzed by real-time RT-PCR after exposure. And the protein levels of the above three mitochondrial transcript factors were detected by Western blot. The results demonstrated that the co-exposure of SO2 and BaP statistically reduced the MMP and activity of COX. The mRNA expression of CO4 was decreased after co-exposure of SO2 and BaP, combined with the depressions of NRF1 and mtTFA mRNA and protein levels. It is indicated that conjunction of SO2 and BaP regulated the expression of NRF1, which then inhibited the transcription and translation of related genomes and resulted in mitochondria damage in mouse lung.