桦褐孔菌多糖对抗结核化疗所致肝脏损伤的保护机制

Mechanism underlying protective effect of Inonotus obliquus polysaccharide on anti-tuberculosis drug induced liver injury

目的:探究桦褐孔菌多糖对利福平和异烟脱导致的肝损伤的保护机制.方法:将100只小鼠随机分为对照组;研究组,研究组分为高剂量组,中剂量组和低剂量组;空白组,每组小鼠20只.除空白组小鼠外,每组小鼠每天灌服异烟脱及利福平,灌服2h后,研究组小鼠分别被灌服不同剂量的桦褐孔菌多糖,对照组小鼠灌服生理盐水,持续4 wk.4 wk后处死各组小鼠,分别测量各组小鼠血清转氨酶、胆红素、肝组织丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxidedismutase,SOD)含量,谷胱甘肽过氧化物酶活性(glutathione peroxidase,GPx)、肝细胞膜转运体多药耐药相关蛋白2(multidrug resistance associated protein2,MRP2)、胆盐输出泵(bile salt export pump,BSEP)、P-糖蛋白(P-glycoprotein,P-GP)、Na^+-牛磺酸钠共转运体(sodium taurocholate cotransporting polypeptide,NTCP)、核因子相关因子2(nuclear factor related factor 2,NRF-2)、谷胱甘肽-S-转移酶Al(glutathione-S-transfer enzyme A1,GSTA1)mRNA含量,肝细胞线粒体8-羟基脱氧鸟苷(8-hydroxy-2 deoxyguanosine,8-OHDG)含量和细胞内活性氧(reactive oxygen species,ROS).对小鼠肝脏进行HE染色后,观察肝脏病理变化.结果:对照组小鼠血清转氨酶、胆红素、肝组织MDA、MRP2、BSEP、P-GP、NRF-2、GSTA1 mRNA、ROS、8-OHDG显著高于空白组小鼠(P<0.05),NTCP、SOD、GPx显著低于空白组小鼠(P<0.05).研究组小鼠血清转氨酶、胆红素,肝组织MDA、MRP2、BSEP、P-GP、NRF-2、GSTA1mRNA、ROS、8-OHDG显著低于对照组小鼠(P<0.05),NTCP、SOD、GPx显著高于对照组小鼠(P<0.05),且各剂量组间存在显著差异(P<0.05).病理切片提示对照组小鼠肝脏病理改变情况明显严重于空白组和各实验组小鼠.结论:桦褐孔菌多糖可以通过降低MRP2、BSEP、P-GP、肿瘤坏死因子-α(tumor necrosis factor alpha)、NRF-2、GSTA1mRNA、ROS、8-OHDG,升高NTCP、SOD、GPx活性来保护由于抗结核化疗导致的肝损伤.

AIM：To explore the mechanism underlying the protective effect of Inonotus obliquus polysaccharide（IOP） on liver injury induced by isoniazid and rifampidn.METHODS：One hundred mice were randomly divided into a normal control group,a model group,and high-,mediumand low-dose IOP groups,with 20 mice in each group.Except the control group,the other groups were intragastrically administered with isoniazid and rifampicin.Two hours later,the mice of the IOP groups were given different doses of IOP,and the mice in the control group were given normal saline.The intervention lasted4 wk.After that,the mice were killed.Serum levels of transaminase and bilirubin,hepatic contents of malondialdehyde（MDA）,superoxide dismutase（SOD）,and glutathione peroxidase（GPX）,expression levels of multidrug resistance associated protein2（MRP2）,bile salt export pump（BSEP）,P-glycoprotein（P-GP）,sodium taurocholate cotransporting polypeptide（NTCP）,nuclear factor related factor 2（NRF-2）,glutathiones-transferase A1（GSTA1）,as well as reactive oxygen species（ROS） and 8-hydroxy-2deoxyguanosine（8-OHDG） levels were detected.Hepatic pathological changes were evaluated by HE staining.RESULTS：Serum levels of transaminase and bilirubin as well as hepatic levels of MDA,MRP2,BSEP,P-GP,NRF-2 and GSTAlwere significantly higher,and the levels of NTCP,SOD,and GPX were significantly lower in the normal control group than in the model group（P 0.05）.Serum levels of transaminase and bilirubin,hepatic levels of MDA,MRP2,BSEP,P-GP,NRF-2 and GSTA1,as well as ROS and 8-OHDG were significantly lower,and the levels of NTCP,SOD,and GPX were significantly higher in mice treated with IOP than in model mice（P 0.05）.The above parameters were significantly different among mice treated with different doses of IOP（P 0.05）.Hepatic pathological changes were obviously more serious in the model group than in the normal control group and IOP treated groups.CONCLUSION：IOP can reduce the levels of MRP2,BSEP,P-GP,NRF-2,GSTA1,ROS,and 8-OHDG,and increase NTCP,SOD and GPX to protect against liver injury caused by antituberculosis drugs.