Nrf2抗氧化通路在CCl_4所致大鼠急性肝损伤中的保护作用

Effect of Nrf2 signal pathway on acute hepatotoxicity induced by CCl_4 in rat

目的研究Nrf2氧化损伤通路在CCl4所致大鼠急性肝损伤中的保护作用。方法将20只雄性Wistar大鼠随机分为溶剂对照组和CCl4组,每组10只,另选10只雄性Wistar大鼠,通过载体进行转基因大鼠雄原核显微注射,获得了目的基因Nrf2-tk整合与特异表达的转基因大鼠,作为CCl4+Nrf2整合组。溶剂对照组静脉给予1%聚山梨酯-80,共4 d,CCl4组和Nrf2-tk整合组静脉给予1%聚山梨酯-80,共4 d,第4天给予1%聚山梨酯-80 30 min后,静脉给予7.5 mg/kg CCl4,24 h后处死大鼠。测定血清中AST、ALT和LDH的水平,分别测定肝脏组织中MDA、GSH、GSSG的含量,并计算GSH/GSSG比值。留取肝脏组织,常规石蜡包埋切片,HE染色,光学显微镜下观察肝脏组织的病理变化。结果和溶剂对照组相比,CCl4组大鼠的血清AST,ALT和LDH的水平明显升高(P<0.05),Nrf2-tk转基因组大鼠的AST,ALT和LDH的水平亦有轻度升高,但差异无统计学意义(P>0.05)。肝脏的MDA含量以及GSH/GSSG比值显示Nrf2-tk整合组可以有效降低CCl4造成的脂质过氧化损伤和谷胱甘肽的消耗,肝脏病理观察结果显示和CCl4组相比,Nrf2-tk整合组明显减轻了CCl4造成的损伤。结论 Nrf2抗氧化损伤通路在CCl4所致大鼠急性肝损伤中的起着重要的保护作用。

Objective To determine the effect of Nuclear factor-erythroid 2-related factor 2（ Nrf2） on acute hephrotoxicity induced by CCl4 in male rat. Methods 20 male Wistar rats were randomly divided into control group and CCl4 group,10 rats in each group,another 10 male Wistar rats were transgenic rats microinjection through the carrier,obtained the Nrf2-tk gene integration and specific transgenic rats,as the CCl4＋ Nrf2 integration group. The groups was given 1% polysorbate 80 for 4 days,Then the CCl4 and CCl4＋ Nrf2 integration group were intraperitoneally injected with a single dose of CCl47. 5 mg·kg- 1and were killed 24 h after CCl4 injection. The serum chemical parameters including asparate aminotransferase（ AST）,alanine aminotransferase（ ALT） and lactate dehydrogenase（ LDH） were measured. Also malonaldehyde（ MDA）,glutathione（ GSH）,oxidized glutathione（ GSSG） levels in the liver as well as glutathione（ GSH）/ oxidized glutathione（ GSSG） ratios were detected. Histopathologic changes in the liver were examined. Results F1 generation TK transgenic rats in liver and testis and other tissues and organs were not detected the transcription of Nrf2-tk,indicating that Nrf2-tk expression in tissues is specific good. Nrf2 significantly reduced serum AST,ALT and LDH levels in a dose-dependent manner. The results of MDA levels and GSH / GSSG ratios in liver and kidney showed that Nrf2reduced CCl4-induced hepatic lipid peroxidation,and ameliorated glutathione depletion. The histopathologic results showed that Nrf2 restrained liver and kidney damage induced by CCl4. Conclusion Nrf2 can effectively protect male rat from acute hepatotoxicity and nephrotoxicity induced by CCl4.