人参皂苷Rg1通过TLR4/MyD88/NF-κB p65通路调控小鼠急性肾损伤诱导的急性肝损伤的机制研究

Mechanism of ginsenoside Rg1 regulating acute hepatic damage induced by acute kidney injury in mice through TLR4/MyD88/NF-κB p65 signaling pathway

目的:探讨人参皂苷Rg1(GRg1)对小鼠急性肾损伤所诱导的急性肝损伤的保护作用及其调控机制。方法:昆明小鼠随机分为假手术(sham)组、模型(model)组、GRg1组和necrostatin-1 (Nec-1)组,每组10只。制备急性肾损伤模型,24 h后收集血液。采用生化试剂盒检测小鼠血清肌酐(SCr)、血尿素氮(BUN)、天冬氨酸转氨酶(AST)、谷氨酸转氨酶(ALT)、丙二醛(MDA)和超氧化物歧化酶(SOD)水平。采用ELISA法检测炎症因子白细胞介素1β(IL-1β)、IL-6、IL-8和肿瘤坏死因子α(TNF-α)的表达。HE染色观察组织病理学改变,采用免疫组织化学和Western blot法检测TLR4、MyD88和NF-κB p65蛋白的表达水平。结果:与假手术组比较,model组小鼠出现明显的肝细胞坏死、肝肾功能减退,血清中SCr、BUN、AST和ALT均显著升高(P<0.01),MDA含量显著上升,SOD活性显著降低(P<0.01),且血清中炎症因子IL-1β、IL-6、IL-8和TNF-α含量显著升高(P<0.01),TLR4、MyD88和NF-κB p65蛋白表达显著增高(P<0.01);与model组相比,GRg1和Nec-1组处理后小鼠肝细胞坏死减轻,肝肾功能显著改善(P<0.01),血清中SCr、BUN、AST和ALT水平显著降低(P<0.01),MDA含量显著降低,SOD活性显著增高(P<0.01),血清中炎症因子IL-1β、IL-6、IL-8和TNF-α含量显著降低(P<0.01),TLR4、MyD88和NF-κB p65蛋白表达显著降低(P<0.01);GRg1组和Nec-1组小鼠上述指标比较差异无统计学意义。结论:GRg1可以改善小鼠急性肾损伤所致急性肝损伤的肝肾功能,其机制可能与抑制TLR4/MyD88/NF-κB p65信号通路有关。

AIM: To investigate the protective effect of ginsenoside Rg1(GRg1) on acute hepatic damage induced by acute kidney injury in mice and its regulatory mechanism. METHODS: Kunming mice were randomly divided into sham group, model group, GRg1 group and necrostatin-1(Nec-1) group, with 10 mice in each group. The acute kidney injury model was prepared, and blood was collected after 24 h. The serum creatinine(SCr), blood urea nitrogen(BUN), aspartate aminotransferase(AST), alanine aminotransferase(ALT), malondialdehyde(MDA), and superoxide dismutase(SOD) levels were measured by biochemical kits. The expression of interleukin-1β(IL-1β), IL-6, IL-8, and tumor necrosis factor-α(TNF-α) were measured by ELISA. Histopathological changes were observed by HE staining, the levels of TLR4, MyD88 and NF-κB p65 were detected by immunohistochemistry and Western blot. RESULTS: Compared with sham group, the model group showed significant hepatocyte necrosis and hepatorenal function were significantly decreased. SCr, BUN, AST and ALT were significantly increased(P<0. 01). The content of MDA was increased and the activity of SOD was decreased dramatically(P<0. 01), the serum levels of IL-1β, IL-6, IL-8 and TNF-α were remarkably increased(P<0. 01). The expressions of TLR4, MyD88 and NF-κB p65 were significantly increased(P<0. 01). Compared with the model group, hepatocyte necrosis was reduced, liver and kidney functions were dramatically improved(P<0. 01), serum levels of SCr, BUN, AST and ALT were decreased significantly(P<0. 01). The content of MDA was decreased and the activity of SOD was increased obviously(P<0. 01). The contents of inflammatory factors IL-1β, IL-6, IL-8, TNF-α were remarkably decreased(P<0. 01). The expressions of TLR4, MyD88 and NF-κB p65 were significantly decreased(P<0. 01). There was no significant difference in the above indexes between GRg1 group and Nec-1 group. CONCLUSION: Ginsenoside Rg1 can improve liver and kidney function in mice with acute hepatic damage induced by acute kidney injury, and the mechanisms may be related to the inhibition of the TLR4/MyD88/NF-κB p65 signaling pathway.