慢性噪声暴露对高脂饮食小鼠肝脏脂代谢的影响

Effect of chronic noise-exposure on liver lipid metabolism in high-fat diet mice

为探究慢性噪声暴露对肝脏脂代谢的影响,将C57BL/6J小鼠随机分为正常对照组和噪声暴露组[持续8周85dB(A)稳态宽带噪声暴露(4h/d)].每组又分为两个亚组,分别给予对照饮食和高脂饮食.实验终点检测小鼠体重增长率、葡萄糖耐量、胰岛素耐量、附睾脂肪重量和肝脏重量、血清白介素-6(IL-6)水平、血清和肝脏甘油三酯(TG)及总胆固醇(TC)水平、肝脏丙二醛(MDA)含量以及c-Jun氨基端激酶(JNK)磷酸化水平.结果显示,噪声暴露引起对照饮食小鼠体重增长率显著降低[(23.30±2.54)%vs.(37.13±3.05)%],代谢效率[(545.20±55.06)kJ/(g·mouse)vs.(352.50±20.92)kJ/(g·mouse)]、血清IL-6水平[(44.68±9.77)pg/mL vs.(20.83±0.81)pg/mL]显著升高;噪声暴露引起高脂饮食小鼠肝脏TG[(0.54±0.07)mmol/g protein vs.(0.30±0.03)mmol/g protein]、MDA含量[(1.98±0.13)mmol/gproteinvs.(1.24±0.03)mmol/gprotein]和JNK磷酸化水平[(1.56±0.19)mmol/gproteinvs.(1.00±0.00)mmol/gprotein]显著升高,提示本研究所采用的慢性噪声暴露可加重高脂饮食小鼠肝脏脂代谢损伤,JNK信号通路可能参与本噪声暴露的肝脏脂代谢损伤效应.

To explore the effect of chronic noise-exposure on liver lipid metabolism,C57BL/6J mice were randomly divided into control group and noise exposure group(85dB(A)SPL broad-band noise,4h/d,for 8weeks).Each group was divided into two subgroups that were given a chow diet or a high-fat diet.The body weight growth rate,glucose tolerance,insulin tolerance,the epididymal fat weight,liver weight,the levels of serum interleukin-6,the levels of serum triglyceride and total cholesterol,the levels of triglyceride and total cholesterol in liver,the levels of malonaldehyde in liver and the phosphorylation levels of c-Jun N-terminal kinase in liver of mice were measured at the end of experiment.The results show that noise exposure can significantly decrease the body weight growth rate(23.30±2.54%vs.37.13±3.05%),significantly increase the metabolic efficiency(545.20±55.06kJ/g/mouse vs.352.50±20.92kJ/g/mouse)and the levels of serum interleukin-6(44.68±9.77pg/mL vs.20.83±0.81pg/mL)of mice fed by chow diet.That noise exposure can significantly increase the levels of triglyceride(0.54±0.07mmol/g protein vs.0.30±0.03mmol/g protein)and malondialdehyde(1.98±0.13nmol/mg protein vs.1.24±0.03nmol/mg protein)and the phosphorylation levels of c-Jun N-terminal kinase(1.56±0.19vs.1.00±0.00)in liver of mice fed by high fat diet.In conclusion,in this study chronic noise exposure can aggravate liver lipid metabolism disorders in high-fat-diet mice,and the activation of c-Jun N-terminal kinase may be involved in the liver lipid metabolism disorders.