环磷酰胺所致小鼠肝损伤的动态变化

Dynamic changes of cyclophosphamide-induced liver injury in mice

环磷酰胺(cyclophosphamide,CPA)是烷化剂类抗肿瘤药物,在体内由细胞色素P450酶代谢为4-羟基环磷酰胺发挥抗肿瘤作用。CPA除引起骨髓抑制、膀胱炎等毒性反应外,还会引起肝损伤。本研究旨在评估CPA在小鼠体内产生肝损伤的动态变化过程。雄性BALB/c小鼠单次腹腔注射CPA(200 mg·kg^-1),分别于0、2、6、12和24 h后采集血清和肝脏样本进行生化和病理检测。动物实验方案经中山大学动物伦理委员会批准。结果表明,小鼠给予CPA 2 h后开始出现肝损伤,在12 h肝损伤最严重,血清天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)和丙二醛(MDA)显著升高,还原型谷胱甘肽(GSH)显著下降,广泛可见肝细胞水肿并伴有空泡变性,而24 h之后肝损伤显著改善。由于CPA产生氧化应激损伤,机体应激性激活核因子红细胞系相关因子-2(nuclear factorerythroid 2-related factor 2,NRF2)信号通路,上调NRF2下游醌氧化还原酶1(quinine oxidoreductase 1,NQO1)、血红素加氧酶-1(heme oxygenase-1,HO-1)、谷氨酰半胱氨酸合成酶催化亚基(glutamate-cysteine ligase catalytic subunit,GCLC)和谷氨酸半胱氨酸连接酶修饰亚基(glutamate cysteine modifier subunit,GCLM)的表达,从而抵抗氧化应激损伤。本研究阐明了CPA所致肝损伤随时间的动态变化过程,并探讨了NRF2介导的机体保护机制的动态变化,为抵抗CPA所致肝损伤提供了科学数据。

Cyclophosphamide(CPA)is one of the most commonly used alkylating agents in the treatment of malignant cancer.CPA is metabolized by cytochrome P450 enzymes into 4-hydroxycyclophosphamide in vivo which can exhibit anti-tumor activity.Metabolic activation of CPA can cause adverse reactions such as myelosup‐pression,cystitis,and liver injury.The aim of this study was to evaluate the dynamic changes of hepatic injury induced by CPA in mice.Male BALB/c mice were injected CPA(200 mg·kg^-1)intraperitoneally.Both serum and liver samples were collected at 0,2,6,12 and 24 hours after dosing.The animal experiment protocol was approved by the Institutional Animal Care and Use Committee at Sun Yat-sen University.The results showed that hepato‐toxicity was observed at 2 hours after CPA dosing,and the most serious liver injury was measured at 12 hours.The level of serum aspartate aminotransferase(AST),alanine aminotransferase(ALT)and malondialdehyde(MDA)was significantly increased,glutathione(GSH)level was significantly decreased,hepatocyte edema and vacuolar degeneration were widely observed in liver tissue,and began to recover 24 hours after dosing.In addition,due to oxidative stress damage caused by CPA,nuclear factor-erythroid 2-related factor 2(NRF2)signaling pathway was activated and the mRNA and protein expression of its downstream targets such as quinine oxidoreductase 1(NQO1),heme oxygenase-1(HO-1),glutamate-cysteine ligase catalytic subunit(GCLC)and glutamate cysteine modifier subunit(GCLM)were up-regulated,which alleviated oxidative stress injury.In a summary,this study demonstrate the dynamic change of CPA-induced liver injury and the NRF2-mediated protective mechanisms,providing new insights into the CPA-induced liver injury.