肌肽对叔丁基过氧化氢诱导肝细胞损伤的修复作用

Repair effect of carnosine on hepatocyte injury induced by tert butyl hydrogen peroxide

肌肽是一种新型的食品补充剂,具有多种生物活性功能,已广泛应用于保健品、功能饮料、美容等领域,但肌肽对肝损伤修复的研究与应用鲜有报道。该文旨在研究肌肽对肝损伤的修复作用并探究其作用机制。肌肽预处理正常人肝细胞(normal human hepatocyte,L-02)12 h,400 mmol/mL叔丁基过氧化氢(tert butyl hydrogen peroxide,TBHP)处理L-02细胞4 h,细胞计数试剂盒-8检测细胞存活率,试剂盒检测谷丙转氨酶(alanine transaminase,ALT)、谷草转氨酶(aspartate transaminase,AST)、活性氧(reactive oxygen species,ROS)、谷胱甘肽(glutathione,GSH)水平,流氏细胞术检测细胞凋亡,蛋白印迹定量分析氧化信号通路与凋亡信号通路的相关蛋白表达。结果表明,肌肽预处理显著降低了L-02细胞外液ALT、AST活性,抑制ROS形成,提高细胞内GSH含量,显著抑制L-02细胞凋亡,上调核红细胞2相关因子2(nuclear factor-erythroid 2-related factor-2,Nrf2)、醌氧化还原酶1(quinone oxidoreductase 1,NQO1)、血红素氧合酶1(heme oxygenase-1,HO-1)、B细胞淋巴瘤-2(B-cell lymphoma 2,Bcl-2)的蛋白表达,下调Kelch样ECH关联蛋白1(Kelch like ECH associated protein 1,Keap1)、磷酸化氨基末端激酶(amino-terminal kinases phosphorylation,p-JNK)、胱天蛋白酶3(caspase-3,Cas-3)的蛋白表达。肌肽通过调控Keap1-Nrf2与JNK-Cas-3信号通路有效修复TBHP诱导的肝细胞损伤。

Carnosine is a new type of food supplement with various bioactive functions,which has been widely used in fields such as health products,functional beverages,cosmetology,etc.However,there are few studies on the research and application of carnosine in the repair of liver injury.This study aimed to verify the repair effect of carnosine on liver injury and explore its mechanism.L-02 cells were pretreated with carnosine for 12 hours and then were treated with 400 mmol/ml tert butyl hydrogen peroxide(TBHP)for 4 hours.The cell viability was assessed using the cell count kit-8(CCK-8),the levels of alanine transaminase(ALT),aspartate transaminase(AST),reactive oxygen species(ROS),and glutathione(GSH)were detected using their respective activity assay kits,the cell apoptosis was measured by flow cytometry,the expression of Keap1-Nrf2 and JNK-Cas-3 signaling pathway-related proteins were quantified by western blot.Results showed that after carnosine pretreatment,the activities of ALT and AST were significantly reduced in the L-02 cell culture medium,the formation of ROS and cell apoptosis were significantly inhibited,and the contents of GSH were significantly increased.The protein expression of nuclear factor-erythroid 2-related factor-2(Nrf2),quinone oxidoreductase 1(NQO1),heme oxygenase-1(HO-1),and B-cell lymphoma 2(Bcl-2)were upregulated by anserine,with the downregulation of Kelch like ECH associated protein 1(Keap1),amino-terminal kinases phosphorylation(p-JNK),and caspase-3(Cas-3).Carnosine effectively alleviated TBHP-induced hepatocyte injury by regulating the Keap1-Nrf2 and JNK-Cas-3 signaling pathways.