【摘要】 目的 探讨Nrf2在脓毒症大鼠免疫器官中的表达规律及姜黄素的干预作用,为临床防治脓毒症提供理论依据。方法 将72只Sprague-Dawley(SD)雄性大鼠随机平分为对照组、实验组、干预组,各组按术后6、12、24和48 h时间点分成不同亚组。实验组与干预组用盲肠结扎穿孔法(CLP法)制备脓毒症急性肝脾损伤大鼠模型。干预组大鼠制模后1 h按100 mg/kg剂量腹腔内注射姜黄素,实验组和对照组同时间点予以等量生理盐水,各组大鼠于各时间点活杀取材。采用心脏采血测定肝功能天门冬氨酸氨基转移酶(AST);免疫印记(Western blot)法测定肝脾组织中Nrf2蛋白的表达情况;肝组织匀浆测定总抗氧化能力(T-AOC)、丙二醛(MDA)。结果①各时间点对照组AST值基本正常,随着脓毒症严重程度增加,实验组较对照组AST值明显升高(P<0.05),干预组较实验组明显改善(P<0.05)。②对照组大鼠肝脾组织中均可检测到Nrf2,各时间点实验组较对照组Nrf2蛋白水平明显下降(P<0.05),干预组较实验组明显升高(P<0.05)。③T-AOC在实验组表达较对照组明显降低(P<0.05),并随时间推移先升高后降低,姜黄素干预后上调(P<0.05)。④MDA在实验组较对照组肝组织中表达明显上升(P<0.05),并随时间推移逐渐升高;与实验组比较,干预组肝组织中MDA表达均明显降低(P<0.05)。结论 ①正常大鼠肝脾组织中均含有Nrf2,且Nrf2直接参与了脓毒症的发生和发展过程,严重感染的打击损害了机体内源性保护系统,Nrf2表达下降,导致机体抗氧化应激反应和自然免疫反应抑制,加重了脓毒症氧化应激引起的急性肝脾损伤。②姜黄素可增加脓毒症时肝脾组织Nrf2表达水平及抗氧化能力,对脓毒症大鼠急性肝脾损伤具有保护作用。更多还原

【Abstract】 Objective To investigate the expression pattern of Nr?2 in immune organs of septic rats and the intervention role of curcumin,to provide theoretical basis for clinical prevention and treatment of sepsis.Methods 72 male Sprague-Dawley(SD) rats were randomly divided into 3 groups:control group,experimental group and intervention group.After operation,3 groups were further divided into subgroups;6 hours,12 hours,24 hours and 48 hours after operation.The septic rat model with acute liver and spleen injury was induced by cecal ligation and puncture(CLP).The rats in the experimental group and the intervention group were access to CLP.The rats in the intervention group were injected with curcumin in the abdomen at a dosage of 100 mg/kg one hour after the operation,while rats in the experimental group and the control group were treated with same amount of saline.Rats in each group were sacrificed at each time point.Blood asparttate aminotran sferase(AST) was detected to evaluate liver function;Western blotting was used to detect expression of Nrf2 protein in the livers and spleens;total antioxidant capacity(T-AOC) and malondialdehyde(MDA) was determined in liver tissue homogenates to evaluate antioxidant ability.Results ①The values of AST in the control group remained in normal range at different time points,while the values in the experimental group was significantly increased compared with the control group when sepsis grew more severely(P < 0.05), while the values in the intervention group was markedly improved compared with the experimental group(P<0.05).②Nrf2 protein was detected in liver and spleen tissue of control group,and its level was significantly decreased in the experimental group compared with the control group at different time points(P < 0.05).Specifically,Nrf2 was obviously higher in the intervention group than in the experimental group at different time points(P < 0.05).③The expression of T-AOC in the experimental group was significantly decreased compared with the control group at different time points(P <0.05),showing the increase-decrease change as time went on,but it was increased by curcumin intervention(P<0.05). ④The expression of MDA in the experimental group was progressively increased and was significantly higher than that in the control group at different time points(P < 0.05).In comparison with the experimental group,the expression of MDA in the intervention subgroup was significantly decreased(P<0.05).Conclusion ①Nrf2 exists in rat liver and spleen and it directly participates in the occurrence and development of sepsis.Severe infection dramatically damages the endogenous protection system,which decreases the activity of Nrf2 and causes inhibition of anti-oxidative stress and natural immune response and in turn exacerbates acute liver and spleen injury through oxidative stress.②In case of sepsis,curcumin may increase Nrf2 expression level and the antioxidant enzyme’s activity in fiver and spleen,which prevents acute liver and spleen injury in sepsis.更多还原