香蜂草苷对脂多糖联合D-氨基半乳糖诱导C57BL/6J小鼠急性肝损伤的保护作用及机制研究

The protective effect and mechanism of Didymin on lipopolysaccharide and D-galactos⁃amine-induced acute liver injury in C57BL/6J mice

目的:探讨香蜂草苷对脂多糖(LPS)联合D-氨基半乳糖(D-Gal)致小鼠急性肝损伤的保护作用及其机制。方法:将90只C57BL/6J小鼠随机分为正常对照组、香蜂草苷(0.8 mg/kg)对照组、模型组、阳性对照(175 mg/kg联苯双酯)组及香蜂草苷低、高剂量(0.4 mg/kg、0.8 mg/kg)组。连续给药14 d后,除正常对照组和香蜂草苷对照组外,其余各组小鼠均腹腔注射LPS和D-Gal建立急性肝损伤模型。检测小鼠血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量,苏木精-伊红(HE)染色法观察肝脏病理组织学改变,酶联免疫吸附试验(ELISA)法检测血清炎症因子白细胞介素1β(IL-1β)、白细胞介素6(IL-6)和肿瘤坏死因子-α(TNF-α)水平,Western blotting法检测NF-κB p65、磷酸化(p-)IKKα/β、IKKα/β蛋白表达。结果:与模型组比较,香蜂草苷低、高剂量组血清ALT、AST活性和MDA含量以及IL-1β、IL-6和TNF-α水平显著降低,SOD活性显著升高(P<0.05);肝脏体积明显减小,充血明显减轻,肝细胞坏死明显改善。模型组p-IKKα/β、NF-κB p65表达较正常对照组显著上调,香蜂草苷低、高剂量组p-IKKα/β、NF-κB p65蛋白表达较模型组显著下调(P<0.05)。结论:香蜂草苷能显著改善LPS/D-Gal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 Didymin on acute liver injury induced by lipopolysaccharide(LPS)and D-galactosamine(D-Gal)in C57BL/6J mice.Methods:Ninety male mice were randomly divided into six groups:normal control group,Didymin control group(0.8 mg/kg),model group,Bifendate-treated group(175 mg/kg),low-dose and high-dose Didymin treated groups(0.4 mg/kg,0.8 mg/kg).After administrated with the corresponding drugs once per day for 14 days,except for the normal group and the Didymin control group,mice in other groups were intraperitoneallyinjected with LPS and D-Gal to establish the model of acute liver injury.The activities of alanine aminotransferase(ALT),aspartate 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 levels of interleukin(IL)-1β,IL-6 and tumor necrosis factor(TNF)-αin serum were detected by enzyme linked immunosorbent assay(ELISA).The protein expressions of NF-κB p65,phosphorylated(p-)IKKα/βand IKKα/βwere detected by Western blotting.Results:Compared with model group,the activities of ALT and AST,the MDA content,and the levels of IL-1β,IL-6 and TNF-αin serum in lowdose and high-dose Didymin groups were significant-ly decreased,while the activity of SOD was increased(P<0.05).Morover,the liver volume was reduced,the congestion was attenuated,and the necrosis of liver cells was significantly improved.In the model group,the p-IKKα/βand NF-κB p65 protein expressions were notably up-regulated compared with the normal control group,but the protein expressions of p-IKKα/βand NF-κB p65in low-dose and high-dose Didymin groups were markedly down-regulated compared with the model group(P<0.05).Conclusion:Didymin can significantly improve the acute liver injury induced by LPS and D-Gal in mice,and its mechanism may be related to the inhibition of NF-κB signaling pathway.