姜黄素减轻急性敌草快中毒肝损伤机制研究

目的 探究姜黄素(CUR)对急性敌草快(DQ)中毒大鼠肝损伤的保护作用及其可能机制。方法 将60只成年雄性 Wistar 大鼠分为6组:氯化钠注射液对照组,DQ染毒组,DQ染毒+低、中、高剂量CUR干预组(50、100、200mg/kg),二甲基亚砜溶剂对照组(DQ+DMSO),每组10只大鼠。造模3d后各组取大鼠心脏血及肝脏组织标本。采用化学比色法检测血清中丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、总胆红素(TBiL)水平,试剂盒检测肝组织丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性水平,酶联免疫吸附法(ELISA)检测肝内核转录因子-κB(NF-κB)、白细胞介素(IL)-6、IL-1β、肿瘤坏死因子-α(TNF-α)等炎性因子表达情况, Western blot 法检测肝内核因子红细胞2相关因子2(Nrf2)、NF-κB、血红素加氧酶1(HO-1)等蛋白表达情况。结果 与对照组相比,DQ组大鼠血清ALT、AST、TBiL、MDA水平以及炎性因子TNF-α、IL-6、IL-1β均升高,而抗氧化酶 SOD、CAT表达则下降,差异均有统计学意义(P<0.01);肝组织NF-κB、Nrf2和HO-1蛋白表达亦见增加(P分别<0.05,<0.01)。与DQ组相比,中、高剂量CUR干预组大鼠血清ALT、AST、TBiL水平以及IL-6、IL-1β、TNF-α 炎性因子含量和MDA水平均明显降低(P<0.01),SOD、CAT表达增加(P<0.01),NF-κB蛋白表达明显降低,Nrf2、HO-1蛋白表达显著增加(P<0.01)。结论 炎症反应及氧化应激是急性DQ中毒肝损伤的重要机制,姜黄素可能通过抑制NF-κB及激活Nrf2/HO-1信号通路,减轻中毒大鼠肝内炎症和氧化应激反应。

Research on mechanism of curcumin in alleviating liver damage by acute diquat poisoning

Objective To investigate the protective effect and its mechanism of curcumin(CUR)on liver injury induced by acute diquat(DQ)poisoning.Methods Sixty experimental male Wistar rats were divided into six groups: saline control group;DQ exposed group;intervened group with low(50mg/kg),medium(100mg/kg)and high(200mg/kg) dose of CUR after DQ exposure; CUR solvent control dimethyl sulfoxide toxicity control group(DQ+DMSO),ten rats each group.After three days of modeling, heart blood and liver tissue samples of rats were taken.The levels of alanine aminotransferase (ALT),aspartate aminotransferase(AST) and total bilirubin (TBiL) in serum of rats were detected by chemical colorimetric method,and the activities of malondialdehyde(MDA),superoxide dismutase(SOD) and catalase(CAT) in liver tissue were detected by assay kits,the enzyme-linked immunosorbent assay(ELISA) was used for detecting the expression of nuclear factor-κ-gene binding (NF-κB), interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α)etc. in liver tissues, and Western blot was used to detect the protein expressions levels of nuclear factor erythroid 2-related factor 2(Nrf 2),NF-κB,and heme oxygenase-1(HO-1).Results The results showed that compared with control group, the serum levels of ALT,AST, TBiL,MDA and the inflammatory factors (TNF-α,IL-6,IL-1β) in DQ group were all significantly increased (P<0.05),theexpression of antioxidant enzymes(SOD and CAT)were decreased,the differences were statistically significant(P<0.01);the expression of NF-κB, Nrf2 and HO-1 proteins in liver tissue also increased(P<0.05 or<0.01,respectively);compared with DQ group,the serum levels of ALT,AST,TBiL,IL-6,IL-1β as well as TNF-α,MDA in the medium and high-dose CUR intervention groups were significantly decreased(P<0.01), the expression of SOD and CAT increased (P<0.01),the expression of NF-κB protein was marked decline, while the protein expression of Nrf 2 and HO-1 was significantly elevated(P<0.01).Conclusion The results suggested that inflammatory response and oxidative stress may be the important mechanism of liver injury by acute diquat poisoning,and curcumin may reduce inflammatory response and oxidative stress in liver of poisoned rats by inhibiting NF-κB and activating Nrf2/HO-1 signaling pathway,thereby alleviating acute liver injury.