血浆联合复方甘草酸苷注射液对LPS/D-GalN诱发的小鼠肝损伤的影响

目的:探讨血浆联合复方甘草酸苷注射液对肝损伤小鼠模型肝损伤的影响。方法:将40只清洁型ICR雄性小鼠随机分为4组(n=10):对照组:仅用生理盐水处理;LPS/D-galN组:仅用LPS/D-GalN处理(LPS50mg/ml,D-GalN 500mg/ml);LPS/DgalN+复方甘草酸苷(CG)组:在LPS/D-GalN诱导后2,4,8h腹腔注射5mg/ml的CG注射液3次;LPS/DgalN+复方苷草酸苷和血浆(CG和Plamsa)组:在LPS/D-GalN诱导后2,4,8h尾静脉注射150μl血浆3次,并腹腔注射CG注射液3次。12h后牺牲小鼠,收集血清和肝组织样本,利用AST和ALT检测试剂盒检测血清中AST和ALT的水平,ELISA法检测肝组织中IL-6、TNF-α和NF-κB的表达变化;肝组织进行HE染色,显微镜下观察肝组织病理学变化。结果:与LPS/D-GalN组对比,LPS/D-GalN+CG组和LPS/D-GalN+CG和Plasma组能够显著降低血清中AST和ALT水平(P0.05);炎症相关因子IL-6和TNF-α,转录因子NF-κB水平也明显降低(P0.05)。结论:血浆联合复方甘草酸苷注射液通过抑制炎症相关因子IL-6和TNF-α,并降低转录因子NF-κB的表达,改善LPS/D-GalN诱发的小鼠肝损伤。     

罗格列酮对D-氨基半乳糖联合脂多糖诱导小鼠急性肝衰竭的保护作用

目的 观察罗格列酮对D-氨基半乳糖(D-GalN)联合脂多糖(LPS)诱导的小鼠急性肝衰竭的保护作用,并研究其可能的作用机制.方法 雄性昆明小鼠随机分为3组:正常组、对照组、治疗组.对照组和治疗组以D-GalN/LPS腹腔注射构建小鼠急性肝衰竭模型,正常组则相应予以生理盐水腹腔注射;治疗组于造模前2 h予以罗格列酮灌胃,正常组和对照组则相应予以生理盐水灌胃.比较各组小鼠24 h存活率、血清丙氨酸氨基转移酶(ALT)和天冬氨酸氨基转移酶(AST)水平、肝组织病变程度及肝组织中肿瘤坏死因子-α(TNF-α)和天冬氨酸特异半胱氨酸蛋白酶-3(Caspase-3)mRNA表达水平.结果 治疗组小鼠24 h存活率明显高十对照组(P<0.05),血清ALT、AST水平明显低于对照组(P<0.05);治疗组与对照组比较,肝组织炎性细胞浸润明显减少,肝细胞以变性为主,未见明显坏死;治疗组小鼠肝组织TNF-α、Caspase-3 mRNA表达水平明显低于对照组(P<0.05).结论 罗格列酮对D-GalN/LPS小鼠急性肝衰竭有保护作用,可改善肝细胞炎症和坏死.降低急性肝衰竭死亡率,其机制可能与罗格列酮下调TNF-α、Caspasc-3表达有关.     

罗格列酮对D-氨基半乳糖联合脂多糖诱导的小鼠急性肝衰竭的保护作用

目的观察罗格列酮对D-氨基半乳糖(D-GalN)联合脂多糖(LPS)诱导的小鼠急性肝衰竭的保护作用,并研究其可能的作用机制。方法雄性昆明小鼠随机分为三组:正常组、对照组和治疗组。对照组和治疗组以D-GalN/LPS腹腔注射构建小鼠急性肝衰竭模型,正常组则相应予以生理盐水腹腔注射;治疗组于造模前2 h予以罗格列酮灌胃,正常组和对照组则相应予以生理盐水灌胃。比较各组小鼠24 h存活率,检测血清丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)水平,肝组织病变程度及肝组织中肿瘤坏死因子-α(TNF-α)和天冬氨酸特异半胱氨酸蛋白酶-3(Caspase-3)mRNA的表达水平。结果治疗组小鼠24 h存活率明显高于对照组(P0.05),血清ALT、AST水平明显低于对照组(P0.05);治疗组与对照组比较,肝组织炎性细胞浸润明显减少,肝细胞以变性为主,未见明显坏死;治疗组小鼠肝组织中TNF-α、Caspase-3 mRNA表达水平明显低于对照组(P0.05)。结论罗格列酮对D-GalN/LPS小鼠急性肝衰竭有保护作用,可改善肝细胞炎症和坏死,降低急性肝衰竭的死亡率,其机制可能与罗格列酮下调TNF-α、Caspase-3的表达有关。     

D-半乳糖胺/脂多糖所致小鼠急性肝衰竭模型正交试验优化研究

目的 通过正交试验优化D-氨基半乳糖(D-GalN)和脂多糖(LPS)致急性肝衰竭模型,确定合理造模剂量,以期使造模更加符合研究需要.方法 选取3个可能影响造模成功率的指标为实验因素:D-GalN剂量、LPS剂量、稀释倍数,每个实验因素选取4个水平,利用L16 (45)正交表安排试验,以小鼠24 h病死率为考察指标.观察小鼠血清ALT、肝组织学改变,肝脏细胞凋亡情况以验证造模效果.结果 优化后理想造模给药方案为D-GalN 350 mg/kg联合LPS 30 μg/kg,混合后稀释3倍,腹腔注射.造模后6h可出现典型肝衰竭表现.结论 优化了D-GalN/LPS致小鼠ALF模型,使其更符合科研需要.     

促肝细胞生长素颗粒剂对大鼠急性肝衰竭的防护作用(摘要)

目的:探讨促肝细胞生长素颗粒剂(促肝康)对大鼠急性肝衰竭的防护作用。方法:用D-氨基半乳糖(D-GalN)和内毒素脂多糖(LPS)制备大鼠急性肝衰竭模型,检测血清ALT、AST、TBil及肿瘤坏死因子α(TNFα)、内毒索(ET)的变化,并观察光镜下肝组织的病理改变。结果:模型组ALT、AST、     

急性药物性肝损伤血清miR-122与肝损伤指标相关性研究

目的探讨急性药物性肝损伤(acute drug-induced liver injury, ADILI)模型血清miR-122与肝损伤指标的相关性。方法选用6～8周龄雄性小鼠随机分为对照组和模型组,模型组通过对乙酰氨基苯酚灌胃法制备ADILI动物模型,模型制备成功后,检测实验小鼠血清AST、ALT、ALP、TBIL、miR-122表达水平;对实验结果进行统计学分析。结果 ADILI模型组在8、16、24、48 h时4个时间点血清miR-122水平与对照组比较差异有统计学意义(P0.05),其余时间点两者水平差异无统计学意义(P0.05)。ADILI模型组在8、16、24 h时3个时间点血清miR-122水平与ALT、AST水平呈正相关,其余时间点无相关性。ADILI模型组不同时间点血清miR-122水平与ALP、TBIL水平无相关性。结论 ADILI模型血清miR-122表达水平明显升高,与肝损伤指标AST、ALT表达水平呈正相关,与肝损伤指标ALP、TBIL表达水平无相关性。     

D-氨基半乳糖联合脂多糖诱导急性肝功能衰竭小鼠血清微小核糖核酸的表达

目的 探讨D氨基半乳糖联合脂多糖诱导急性肝功能衰竭小鼠血清微小核糖核酸(miRNA)的表达变化以及与肝组织miRNA的相关性.方法 Balb/C清洁级小鼠40只分为两组,模型组32只,对照组8只.模型组应用D-氨基半乳糖联合脂多糖诱导Balb/C小鼠急性肝功能衰竭,对照组腹腔注射0.9％氯化钠溶液1 mL.模型组给药后0、3、5和7h分别处死小鼠各8只,采集血清及肝组织,观察小鼠给药后肝功能生物化学指标及肝组织病理学变化.抽提血清及肝组织miRNA,取0、5和7h肝组织进行锁核酸(LNA)-miRNA微阵列分析,并用实时定量反转录PCR检测miRNA.组间均数比较用单因素方差分析,相关性分析采用Pearson和Spearman相关分析.结果 随着小鼠急性肝功能衰竭的发生,肝组织miRNA的表达发生显著变化,共有21个miRNA明显上调,27个miRNA明显下调,其中miRNA-122和miRNA-1187表达下调,miRNA-146a、miRNA-155表达上调.经PCR验证发现小鼠肝组织miRNA 122和miRNA-1187表达逐渐下调,血清miRNA-122和miRNA-1187的表达则逐渐上调;炎性相关的miRNA 146a和miRNA-155在肝组织和血清中表达均明显增加.小鼠miRNA-122和miRNA-1187在组织与血清中的表达呈负相关(r值分别=-0.477和-0.420,P值分别=0.0089和0.0231),而miRNA-155在组织与血清中表达呈正相关(r=0.678,P=0.0001).小鼠血清miRNA 122(r值分别=0.571和0.554)、miRNA-1187(r值分别=0.471和0.542)的相对表达量与ALT和AST水平均呈正相关(均P＜0.05).血清miRNA 122和miRNA-1187在给药5h上升显著,早于血清转氨酶的变化.结论急性肝功能衰竭小鼠肝组织和血清miRNA-122和miRNA-1187的表达呈负相关,血清中miRNA-122、miRNA-1187的变化早于血清转氨酶的变化,有可能成为早期预测肝损伤的血清标志物.     

抑制糖原合成酶激酶-3β活性减少肝细胞凋亡保护D-氨基半乳糖／脂多糖诱导的小鼠急性肝衰竭损伤

目的：研究细胞信号分子糖原合成酶激酶-3β（glycogen synthase kinase-3β,GSK-3β）对 D-氨基半乳糖／脂多糖（D-GalN／LPS）联合诱导的小鼠急性肝衰竭肝细胞凋亡的影响。方法腹腔注射 D-GalN／LPS 建立小鼠急性肝衰竭模型。实验动物分为对照组、模型组、SB216763干预组（建模前2 h 腹腔注射）。检测血清 ALT、AST,TUNEL 法测定肝细胞凋亡,免疫荧光染色法及比色法检测 Caspase-3活性,Western 印迹检测 Cleaved Caspase-3蛋白表达。多组样本均数的两两比较采用一步法 ANOVA 分析。结果 GSK-3β活性升高促进了在小鼠急性肝衰竭的发生和发展：抑制 GSK-3β活性可以显著改善肝脏功能,血清 ALT、AST 水平明显下降。SB216763干预组 ALT 与 AST 水平分别为（961．1±356．0）IU／L和（2709．9±423．9）IU／L,SB216763干预组与模型组相比,Caspase-3活性降低,TUNEL 方法检测肝细胞凋亡减少,并且Cleaved Caspase-3的蛋白表达降低。结论在 D-GalN／LPS 诱导的小鼠急性肝衰竭中,抑制 GSK-3β活性可能通过抑制肝细胞凋亡而改善肝损伤。因此,对信号分子 GSK-3β活性进行干预有可能为急性肝衰竭的治疗提供一个新的靶点。     

微小RNA在肿瘤坏死因子α介导的急性肝功能衰竭小鼠体内的表达谱及其作用

目的 了解微小RNA(miRNA)在急性肝功能衰竭小鼠模型中的表达谱及对其发病机制的调控作用.方法 将BALB/c小鼠85只分为4组,模型组40只用D-氨基半乳糖(D-GalN)联合脂多糖(LPS)腹腔注射建立肝功能衰竭模型,D-GalN单药组20只、LPS单药组20只和对照组5只分别予D-GalN、LPS和0.9%NaCl溶液腹腔注射.在给药后0、5和7 h观察小鼠肝脏组织学变化,0、1、3、5、7和9 h留取小鼠血清和肝脏组织标本.采用实时定量PCR方法检测小鼠血清及肝组织中炎性细胞因子(TNF-α和IL-6)表达水平;采用miRNA微阵列(microarray)检测小鼠肝脏中miRNA的表达谱,实时定量PCR验证其表达.体外LPS诱导小鼠巨噬细胞Raw264.7活化,诱导不同时间点收集细胞检测细胞miRNA的表达情况.组间均数比较用单因素方差分析,相关性分析采用Pearson和Spearman相关分析.结果 miRNA微阵列发现小鼠急性肝功能衰竭发病过程中miRNA的表达谱发生了明显变化,与对照组相比,模型组有97个miRNA表达变化显著(P＜0.01),其中21个miRNA在给药后5 h和7 h均表达上调,27个miRNA均表达下调,进一步PCR验证得到miR-146a和miR-155随给药时间延长表现为持续性上调,且miR-155表达与TNF-α和IL-6表达均具有良好的相关性.体外实验进一步发现miR-146a和miR-155在活化的巨噬细胞中表达上调.结论 在小鼠急性肝功能衰竭发病过程中,伴随着miRNA表达谱的变化,炎性反应相关miR-146a和miR-155明显上调,可能在急性肝功能衰竭的免疫发病机制中发挥重要的调控作用.     

Urotensin Ⅱ在急性肝衰竭小鼠肝组织中的表达及损伤作用

目的:探讨Urotensin Ⅱ(UⅡ)在急性肝衰竭(acute liver failure,ALF)小鼠肝组织中的表达及损伤作用.方法:♂Balb/c小鼠随机分成4组(每组6只):正常对照组(A组)、预处理对照组(B组)、模型组(C组)和预处理模型组(D组).模型动物以脂多糖(lipopolysaccharide,LPS)/D-半乳糖胺(D-galactosamine,D-GalN)腹腔注射,预处理动物在造模前30min,用UⅡ受体拮抗剂Urantide0.6mg/kg尾静脉注射.LPS/D-GalN攻击12h后,采集血清和肝组织标本,并观察24h小鼠存活情况;采用Reitman-Frankel法检测血清丙氨酸氨基转移酶(alanine aminotransferase,ALT)和天冬氨酸氨基转移酶(aspartate amino-transferase,AST)活性水平;采用HE染色显微镜观察肝组织损伤程度;RT-PCR法检测UⅡ及其受体UTmRNA的表达;ELISA法检测血清UⅡ多肽分泌水平;免疫组织化学方法检测肝组织UⅡ多肽及其UT受体蛋白质表达.结果:C组小鼠死亡率为66.7%,A、B和D组所有动物均存活;LPS/D-GalN攻击引起C和D组小鼠血清ALT和AST水平显著升高(P<0.01),而D组较C组显著降低(2271.09U/L±102.24U/Lvs1160.67U/L±258.32U/L,1569.42U/L±204.04U/Lvs1030.31U/L±108.09U/L,P<0.01);C组小鼠肝组织结构破坏明显,见大片出血性坏死及炎症表现,D组肝组织结构保持完整,仅有局灶性出血坏死,炎症明显减轻;C和D组小鼠血清UⅡ多肽水平较A和B组高(P<0.01),但D组较C组明显降低(3.73g/L±0.52g/Lvs1.90g/L±0.27g/L,P<0.01);LPS/D-GalN诱导了C和D组小鼠肝组织UⅡ和UT的mRNA及蛋白质高水平表达,而D组的表达水平较C组显著降低(P<0.01).结论:LPS/D-GalN可诱导ALF小鼠肝组织表达和分泌UⅡ,并促进肝组织UT受体的表达;UⅡ的表达与分泌可能存在正反馈调控机制;UⅡ/UT受体介导了LPS/D-GalN诱导的ALF的发生.     

雷帕霉素对急性肝功能衰竭大鼠Toll样受体-4表达的影响

目的 探讨雷帕霉素抑制Janus激酶/信号转导和转录激活子(JAK/STAT)通路对急性肝功能衰竭大鼠Toll样受体(TLR)-4基因表达的影响.方法采用腹腔注射D-氨基半乳糖(D-GalN)800 mg/kg和脂多糖(LPS)8 μg/只,建立急性肝功能衰竭大鼠模型,分别在注射D-GalN和LPS后2、6、12、24、48 h 5个时间点留取大鼠血及肝脏标本.SD大鼠分为对照组(n=6)、急性肝功能衰竭模型组(n=30)、STAT抑制剂雷帕霉素(RPM)干预组(n=30),在各不同时间点检测ALT、AST.ELISA法检测血清TNF-α、IL-6水平,RT-PCR法检测大鼠肝组织TLR-4 mRNA表达.数据行t检验.结果急性肝功能衰竭组大鼠在造模后2 h TNF-α、IL-6水平均显著升高,6 h达峰值,RPM可明显抑制TNF-α、IL-6水平.急性肝功能衰竭组大鼠6、12、24、48 h肝组织中TLR-4 mRNA分别为0.745±0.135、1.092±0.175、1.115±0.152和0.812±0.130,RPM干预后分别为0.545±0.118、0.798±0.124、0.857±0.109和0.595±0.152,各时间点两组比较,差异均有统计学意义(t值分别为2.726、3.349、3.382和2.567,均P＜0.05).TLR-4 mRNA表达与ALT、AST均呈正相关(r值分别为0.722、0.712,均P＜0.01).结论抑制JAK/STAT通路可明显下调急性肝功能衰竭大鼠肝组织TLR-4表达,JAK/STAT通路可能参与急性肝功能衰竭过程中TLR-4mRNA表达的调控.     

IL-33及其受体ST2在D-GalN/LPS诱导的急性肝功能衰竭小鼠中的表达及意义

目的研究D-GalN/LPS诱导的急性肝衰竭小鼠中IL-33及其受体ST2的表达及意义。方法腹腔注射DGaIN(900 mg/kg)/LPS(10μg/kg)诱导急性肝衰竭小鼠模型。通过q-PCR、Westcrn印迹、ELISA、免疫组织化学染色等实验技术检测IL-33及其受体ST2在不同时间点的动态变化。结果急性肝衰竭小鼠肝内的IL-33 mRNA水平随着肝损伤加重不断增高,肝衰竭时上升至峰值,D-GalN/LPS诱导后7 h,肝组织表现为明显坏死。而肝内ST2L受体蛋白含量在DGalN/LPS诱导后3 h,未出现明显的肝细胞损伤前已显著升高,之后不断下降,到7 h肝衰竭时其水平降至最低。此外,外周血清中IL-33蛋白水平亦随时间持续升高,在7 h肝衰竭时达高峰,与IL-33 mRNA的动态变化相一致。然而血清sST2蛋白水平在0 h和3 h肝细胞损伤的早期无明显差异,但在5 h肝细胞损伤的中期却显著升高,之后又显著降低。免疫组织化学染色显示急性肝衰竭小鼠肝内IL-33来源于血管内皮细胞和肝血窦细胞核内。结论 IL-33及其受体ST2随时间的动态变化与急性肝衰竭的病情进展存在紧密联系,提示IL-33/ST2轴参与了急性肝衰竭的发生发展过程。     

The therapeutic effect of CORM-3 on acute liver failure induced by lipopolysaccharide/D-galactosamine in mice

BACKGROUND: Acute liver failure(ALF) is a severe and lifethreatening clinical syndrome resulting in a high mortality and extremely poor prognosis. Recently, a water-soluble CO-releasing molecule(CORM-3) has been shown to have anti-inflammatory effect. The present study was to investigate the effect of CORM-3 on ALF and elucidate its underlying mechanism.METHODS: ALF was induced by a combination of LPS/D-Gal N in mice which were treated with CORM-3 or inactive CORM-3(i CORM-3). The efficacy of CORM-3 was evaluated based on survival, liver histopathology, serum aminotransferase activities(ALT and AST) and total bilirubin(TBi L). Serum levels of inflammatory cytokines(TNF-α, IL-6, IL-1β and IL-10) and liver immunohistochemistry of NF-κB-p65 were determined; the expression of inflammatory mediators such as i NOS, COX-2 and TLR4 was measured using Western blotting.RESULTS: The pretreatment with CORM-3 significantly improved the liver histology and the survival rate of mice compared with the controls; CORM-3 also decreased the levels of ALT, AST and TBi L. Furthermore, CORM-3 significantly inhibited the increased concentration of pro-inflammatory cytokines(TNF-α, IL-6 and IL-1β) and increased the anti-inflammatory cytokine(IL-10) productions in ALF mice. Moreover, CORM-3 significantly reduced the increased expression of i NOS and TLR4 in liver tissues and inhibited the nuclear expression of NF-κB-p65. CORM-3 had no effect on the increased expression of COX-2 in the ALF mice. An i CORM-3 failed to prevent acute liver damage induced by LPS/D-Gal N. CONCLUSION: These findings provided evidence that CORM-3 may offer a novel alternative approach for the management of ALF through anti-inflammatory functions.     

内毒素预适应减轻急性肝功能衰竭中热休克蛋白27的作用

目的研究热休克蛋白27（HSP27）介导内毒素（LPS）预适应减轻急性肝功能衰竭（ALF）的作用机制。方法实验动物为雄性C57BL/6小鼠。将小鼠分为5组,对照组为正常C57BL/6小鼠;肝功能衰竭组小鼠以LPS10μg/kg＋D-半乳糖胺700 mg/kg,用1 mL0.9%氯化钠溶液溶解后腹腔内注射,建立急性肝功能衰竭的模型;LPS预处理组小鼠经LPS预适应24 h后,建立急性肝功能衰竭的模型;HSP27干扰组小鼠和转染对照组小鼠分别以尾静脉注射包装有干扰HSP27表达的短发夹RNA的重组腺病毒以及对照空病毒,成功干扰HSP27表达后,经LPS预处理,建立急性肝功能衰竭模型。通过比较各组ALT和AST水平,评价肝组织病理损伤程度,以及检测肝组织内TNF-α、IL-6mRNA水平,观察HSP27对LPS预适应减轻急性肝功能衰竭的影响。结果 LPS预适应可明显减轻Galn/LPS所致的肝损伤,干扰HSP27的表达后,小鼠血清ALT和AST明显升高,肝组织病理损伤和炎性反应加重（P〈0.05）。下调HSP27的表达水平后,LPS预适应的保护作用几乎完全消失。结论 LPS预适应可以减轻小鼠的急性肝损伤,HSP27在这一效应中发挥重要作用。     

Sphingosine kinase 1 dependent protein kinase C-δ activation plays an important role in acute liver failure in mice

AIM: To investigate the role of protein kinase C (PKC)-δ activation in the pathogenesis of acute liver failure (ALF) in a well-characterized mouse model of D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced ALF.METHODS: BALB/c mice were randomly assigned to five groups, and ALF was induced in mice by intraperitoneal injection of D-GaIN (600 mg/kg) and LPS (10 μg/kg). Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels at different time points within one week were determined using a multiparameteric analyzer. Serum levels of high-mobility group box 1 (HMGB1), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10 as well as nuclear factor (NF)-κB activity were determined by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after ALF induction were assessed by hematoxylin and eosin staining. Expression of PKC-δ in liver tissue and peripheral blood mononuclear cells (PBMCs) was analyzed by Western blot.RESULTS: The expression and activation of PKC-δ were up-regulated in liver tissue and PBMCs of mice with D-GalN/LPS-induced ALF. Inhibition of PKC-δ activation with rottlerin significantly increased the survival rates and decreased serum ALT/AST levels at 6, 12 and 24 h compared with the control group (P < 0.001). Rottlerin treatment also significantly decreased serum levels of HMGB1 at 6, 12, and 24 h, TNF-α, IL-6 and IL-1 β at 12 h compared with the control group (P < 0.01). The inflammatory cell infiltration and necrosis in liver tissue were also decreased in the rottlerin treatment group. Furthermore, sphingosine kinase 1 (SphK1) dependent PKC-δ activation played an important role in promoting NF-κB activation and inflammatory cytokine production in ALF.CONCLUSION: SphK1 dependent PKC-δ activation plays an important role in promoting NF-κB activation and inflammatory response in ALF, and inhibition of PKC-δ activation might be a potential therapeutic strategy for this disease.     

组织蛋白酶B抑制剂对小鼠急性肝功能衰竭的保护作用及机制

目的 探讨组织蛋白酶B抑制剂对小鼠急性肝功能衰竭的保护作用及机制.方法 将雄性昆明种小鼠45只分为对照组、模型组和保护组,每组各15只.模型组和保护组一次性腹腔注射脂多糖/D-氨基半乳糖(LPS/D-GalN),保护组于造模前30 min予组织蛋白酶B抑制剂(CA-074me)腹腔注射,而模型组、对照组分别注射同等体积的0.5％氯化钠溶液作为对照,给药后6h分别取血清、肝组织标本.检测肝功能变化及凝血酶原时间(PT),观察肝脏病理改变,末端转移酶标记技术(TUNEL)检测肝细胞凋亡,免疫组织化学分析细胞色素c表达,RT-PCR检测肝组织中天冬氨酸特异性半胱氨酸蛋白酶-3(Caspase-3)的表达.另取75只小鼠按上述方法分组处理,每组25只,比较各组小鼠24 h存活率.统计学处理采用f检验和x2检验.结果 保护组小鼠24 h存活率明显高于模型组分别为76％(19/25)和36％ (9/25)(x2=8.12,P＜0.05);保护组小鼠血清ALT[(568.50±45.68)U/L比(1394.55±78.58) U/L]、AST[(755.16±51.14) U/L比(1 488.72±64.62) U/L]、TBil[ (22.82±2.04)μmol/L比(52.08±4.10) μmol/L]和PT[(14.26±0.32)s比(17.40±0.30)s]水平均明显低于模型组(均P＜0.05);与模型组比较,保护组小鼠肝组织炎性细胞浸润明显减少,肝细胞坏死程度明显减轻,凋亡指数明显下降[(18.4±2.6)％比(30.4±2.8)％,P＜0.05];保护组小鼠肝组织中细胞色素c[(0.19±0.02)比(0.33±0.05)]和Caspase-3 [(0.18±0.03)比(0.34±0.05)]表达水平明显低于模型组(均P＜0.05).结论 CA-074me对小鼠急性肝功能衰竭具有保护作用,可减轻肝细胞炎性反应、坏死和凋亡,降低急性肝功能衰竭的病死率,其机制可能与CA-074me下调细胞色素c和Caspase-3的表达有关.     

Inhibition of sphingosine kinase 1 ameliorates acute liver failure by reducing high-mobility group box 1 cytoplasmic translocation in liver cells

AIM: To determine the therapeutic potential of sphingosine kinase 1(Sphk1) inhibition and its underlying mechanism in a well-characterized mouse model of D-galactosamine(D-Gal N)/lipopolysaccharide(LPS)-induced acute liver failure(ALF).METHODS: Balb/c mice were randomly assigned to different groups,with ALF induced by intraperitoneal injection of D-Ga IN(600 mg/kg) and LPS(10 μg/kg). The Kaplan-Meier method was used for survival analysis. Serum alanine aminotransferase(ALT) and aspartate aminotransferase(AST) levels at different time points within one week were determined using a multi-parametric analyzer. Serum high-mobility group box 1(HMGB1),tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,IL-6,IL-10,and sphingosine-1-phosphate were detected by enzyme-linked immunosorbent assay. Hepatic morphological changes at 36 h after acute liver injury induction were assessed by hematoxylin and eosin staining. HMGB1 expression in hepatocytes and cytoplasmic translocation were detected by immunohistochemistry. Expression of Sphk1 in liver tissue and peripheral blood mononuclear cells(PBMCs) was analyzed by Western blot.RESULTS: The expression of Sphk1 in liver tissue and PBMCs was upregulated in Gal N/LPS-induced ALF. Upregulated Sphk1 expression in liver tissue was mainly caused by Kupffer cells,the resident macrophages of the liver. The survival rates of mice in the N,Ndimethylsphingosine(DMS,a specific inhibitor of Sph K1) treatment group were significantly higher than that of the control group(P 0.001). DMS treatment significantly decreased the levels of serum ALT and AST at 6,12,and 24 h compared with that of the control group(P 0.01 for all). Serum HMGB1 levels at 6,12,and 24 h,as well as serum TNF-α,IL-6,and IL-1β levels at 12 h,were significantly lower in the DMS treatment group than in the control group(P 0.01 for all). Furthermore,hepatic inflammation,necrosis,and HMGB1 cytoplasm translocation in liver cells were significantly decreased in the DMS treatment group compared to the control group(43.72% ± 5.51% vs 3.57% ± 0.83%,χ2 = 12.81,P 0.01).CONCLUSION: Inhibition of Sph K1 ameliorates ALF by reducing HMGB1 cytoplasmic translocation in liver cells,and so might be a potential therapeutic strategy for this disease.     

Sinapic acid ameliorates D-galactosamine/lipopolysaccharide-induced fulminant hepatitis in rats: Role of nuclear factor erythroid-related factor 2/heme oxygenase-1 pathways

BACKGROUND Sinapic acid(SA)has been shown to have various pharmacological properties such as antioxidant,antifibrotic,anti-inflammatory,and anticancer activities.Its mechanism of action is dependent upon its ability to curb free radical production and protect against oxidative stress-induced tissue injuries.AIM To study the hepatoprotective effects of SA against lipopolysaccharide(LPS)/Dgalactosamine(D-GalN)-induced acute liver failure(ALF)in rats.METHODS Experimental ALF was induced with an intraperitoneal(i.p.)administration of 8μg LPS and 800 mg/kg D-GalN in normal saline.SA was administered orally once daily starting 7 d before LPS/D-GalN treatment.RESULTS Data showed that SA ameliorates acute liver dysfunction,decreases serum levels of alanine transaminase(ALT),and aspartate aminotransferase(AST),as well as malondialdehyde(MDA)and NO levels in ALF model rats.However,pretreatment with SA(20 mg/kg and 40 mg/kg)reduced nuclear factor kappalight-chain-enhancer of activated B cells(NF-κB)activation and levels of inflammatory cytokines(tumor necrosis factor-αand interleukin 6).Also,SA increased the activity of the nuclear factor erythroid-related factor 2/heme oxygenase-1(Nrf2/HO-1)signaling pathway.CONCLUSION In conclusion,SA offers significant protection against LPS/D-GalN-induced ALF in rats by upregulating Nrf2/HO-1 and downregulating NF-κB.