异牡荆素对硫代乙酰胺诱导的小鼠急性肝损伤的保护作用及其机制

The protective effect and mechanism of isovitexin on thioacetamide induced acute liver injury in mice

目的:探讨异牡荆素对硫代乙酰胺(TAA)致小鼠急性肝损伤的保护作用及其机制。方法:将90只小鼠随机分为正常对照组、异牡荆素对照组(100 mg/kg)、TAA模型组、阳性组(175 mg/kg联苯双酯),异牡荆素高、低剂量组(100 mg/kg、25 mg/kg)。连续给药15 d后,除正常组和异牡荆素对照组外,其余各组小鼠均注射TAA复制急性肝损伤模型。检测小鼠血清中谷丙转氨酶(ALT)、谷草转氨酶(AST)、丙二醛(MDA)及超氧化物歧化酶(SOD)的活性,苏木精-伊红(HE)染色法观察肝脏病理组织学改变,ELISA试剂盒检测小鼠血清中炎症因子水平以及氧化应激相关指标的变化,Western blot检测NF-κBp65、p-IKB-α、IKB-α的蛋白表达。结果:与TAA模型组比较,异牡荆素高、低剂量组血清中ALT、AST和MDA活性显著降低,SOD活性显著升高(P<0. 05);异牡荆素高、低剂量组能明显降低炎症因子白细胞介素(IL)-1β、IL-6和肿瘤坏死因子(TNF)-α的水平并且提高IL-10的水平(P<0. 05);HE染色结果显示,与TAA模型组比较,异牡荆素高、低剂量组能够明显减轻TAA诱导所致的肝细胞破碎、坏死,高剂量组保护作用较好;Western blot结果显示,TAA模型组中,NF-κB信号通路相关蛋白p-IKB-α、NF-κB p65显著上调,而异牡荆素高、低剂量组能显著抑制p-IKB-α、NF-κB p65的蛋白表达水平(P<0. 05),减轻炎症反应。结论:异牡荆素能显著改善TAA诱导的小鼠急性肝损伤,其机制可能与抑制NF-κB信号通路有关。

Objective: To investigate the protective effect and its mechanism of isovitexin on acute liver injury induced by thioacetamide(TAA)in mice. Methods: Ninety mice were randomly divided into normal control group,isovitexin control group(100 mg/kg),TAA model group,positive group(175 mg/kg biphenyl diester),high dose and low dose isovitexin groups(100 mg/kg,25 mg/kg). After 15 days of continuous administration,except for the normal group and the isovitexin control group,mice in other groups were injected with TAA to establish the model of acute liver injury. The activities of alanine aminotransferase(ALT),aspertate aminotransferase(AST),malondialdehyde(MDA),and superoxide dismutase(SOD)in the serum of mice were detected. The histopathological changes of liver were observed by hematoxylin-eosin(HE)staining. The changes of inflammatory factors and oxidative stress related indexes in serum of mice were detected by ELISA kit. The protein expressions of NF-κBp65,p-IKB-α,and IKB-α were detected by Western blot. Results: Compared with TAA model group,the activities of ALT,AST,and MDA in serum of high dose and low dose isovitexin groups were significantly decreased,while the activity of SOD was significantly increased(P<0. 05). The high does and low dose isovitexin groups could significantly decreased the levels of interleukin(IL)-1β,IL-6,and tumor necrosis factor(TNF)-α and increased the level of IL-10(P<0. 05). The results of HE staining showed that,compared with the TAA model group,the high dose and low dose isovitexin groups could significantly reduce the fragmentation and necrosis of hepatocytes induced by TAA,and the protective effect of the high dose group was better. Western blot results showed that in TAA model group,NF-κB signal pathway related proteins p-IKB-α and NF-κB p65 were significantly up-regulated,while high dose and low-dose isovitexin groups could significantly inhibit the protein expression levels of NF--IKB-α and NF--κB p65 and reduce inflammatory reaction. Conclusion: Isovitexin can significantly improve the acute liver injury induced by TAA in mice,and its mechanism may be related to the inhibition of NF-κB signal pathway.