赖氨酰氧化酶样蛋白1在日本血吸虫感染小鼠肝脏中的动态表达

LOXL1 dynamic expression of the liver in mice infected with Schistosoma japonicum

目的观察赖氨酰氧化酶(LOX)家族中的赖氨酰氧化酶样蛋白1(LOXL1)及相关胶原蛋白在日本血吸虫感染小鼠肝脏中的动态表达,探讨其在日本血吸虫肝纤维化形成中的作用。方法采用日本血吸虫感染的小鼠肝纤维化模型,于感染后第6、9、12周剖杀小鼠,收集其血清和肝脏标本;以HE和天狼星红两种染色方法分别观察并评价小鼠肝脏纤维化的进展程度;同时检测小鼠血清转氨酶水平。以免疫印迹(Western blot)和荧光定量PCR(qPCR)方法分别检测肝组织LOXL1、Ⅰ型胶原蛋白(Col1)及α-肌动蛋白(α-SMA)的表达并分析其含量的变化;并对血清中的可溶性和不可溶性胶原进行测定,以判断胶原交联情况。结果HE和天狼星红染色结果显示,随感染时间延长,小鼠肝纤维化也随之进展,在感染第9周肝纤维化程度最为严重,随后进入慢性肝纤维化期,纤维化程度减轻。Western blot和qPCR结果显示,LOXL1和其他纤维化指标表达情况类似,均在感染第9周时表达量明显上调;可溶性胶原含量在感染第9周时达峰值后下降,而不可溶性胶原含量则持续上升。结论LOXL1与血吸虫肝脏纤维化过程中纤维交联存在相关关系,可能在肝纤维化进程中起到促进作用。

Objective To observe the dynamic expression of recombinant lysyl oxidase like protein 1(LOXL1)in the lysine oxidase family in the liver of C57BL/6 mice infected with Schistosoma japonicum and explore its role in hepatic fibrosis.Methods Mice were infected subcutaneously with cercariae of S.japonicum,and sacrificed with euthanasia in 6,9 and 12 weeks after infection.The sera and liver tissues were collected.The levels of liver fibrosis in mice was dynamically evaluated by HE and Sirius red staining,and the serum transaminases were detected.The dynamic expression levels of collagen type Ⅰ(Col1),LOXL1 and α-smooth muscle actin(α-SMA)in liver tissues were determined respectively by Western blot and qPCR.Finally,the dynamic levels of soluble and insoluble collagens were detected.Results The result of HE and Sirius red staining showed that hepatic fibrosis levels increased at 6 weeks,peaked at 9 week,and decreased at 12 week in response to S.japonicum infection.Western blot and q-PCR showed that the expression levels of LOXL1,Col1α1,Col3α1 and α-SMA was significantly up regulated and reached maximum at the 9th week in response to S.japonicum infection.Soluble collagen protein levels reached maximum at the 9th week.and decreased at 12 week,however insoluble collagen protein levels continued to increase.Conclusion There may be a correlation between LOXL1 and fiber cross-linking in the process of hepatic fibrosis in S.japonicum,and it plays a role in promoting hepatic fibrosis.