硫代乙酰胺诱导的斑马鱼急性肝损伤模型

目的：研究斑马鱼幼体是否适于作为药源性肝损伤的评价模型并探讨其毒理机制。方法：将发育正常的3-dpf斑马鱼幼鱼暴露于不同浓度的硫代乙酰胺溶液中72 h，显微镜下活体观察斑马鱼幼鱼给药后的畸形表型和肝脏形态的变化；通过油红O染色观察肝脏脂肪含量变化；通过组织切片和H&E染色观察幼鱼肝脏细胞结构的变化；用RT-PCR方法检测幼鱼肝脏病理标志基因和凋亡相关基因转录水平的变化。结果：活体观察显示斑马鱼幼鱼在给药后出现不同程度的畸形表型；病理学显示肝脏细胞核结构异常，细胞质出现大量脂肪空泡；油红O染色显示肝细胞有脂肪堆积；RT-PCR的结果表明硫代乙酰胺能够上调脂肪肝和肝纤维化相关基因；能够促进凋亡基因Bid和Bax-2表达，并抑制促存活基因Mcl-1b和Bcl-2的表达。结论：硫代乙酰胺对斑马鱼幼鱼肝脏产生的毒性作用与对哺乳动物肝脏的损伤相似。斑马鱼可以作为快速评价、筛选和研究药物肝脏毒性的模式动物。

Objective: To investigate if zebrafish larvae are suitable as a model for evaluation of drug-induced liver toxicity and investigate the correlated mechanism. Methods: Zebrafish larvae at 3-dpf were exposed to the thioacetamide solution,a positive compound of hepatotoxicity,for 72 h at different concentrations.Viviperception of the larvae abnormal phenotype and liver morphology were carried out under a microscope to observe changes;then,oil red O staining was performed to observe for the changes of fat content in the liver,and the structure changes in liver cells were observed through tissue section and H&E staining.Gene levels of some liver pathological markers and apoptosis were detected by RT-PCR. Results: After administration,the larvae abnormal phenotypes were induced by thioacetamide according to viviperception.Histological analysis showed abnormal nucleus and a number of big fat vacuoles in the hepatocytes.Oil red O stain also showed the accumulation of fat droplets.RT-PCR results showed thioacetamide could up-regulate genes related to fatty liver and fibrosis,enhance expression of two apoptotic genes Bid and Bax-2,and inhibit two prosurvival genes Mcl-1b and Bcl-2. Conclusion: Thioacetamide can induce liver injury in zebrafish larvae,which shows a similar effect on zebrafish larvae to mammalian,indicating that zebrafish larvae may act as a promising model for evaluation,screening and mechanism study of drug-induced hepatotoxicity.