双环醇对刀豆蛋白A引起肝损伤小鼠肝脏基因表达谱的影响

本实验研究双环醇对刀豆蛋白A(concanavalin A，Con A)静脉注射引起免疫性肝损伤小鼠肝脏基因表达谱变化的影响，探讨双环醇肝保护作用的分子机制。小鼠于注射Con A 26.5 mg·kg^-1前24、 8及1 h分别口服双环醇250 mg·kg^-1。测定血清丙氨酸转氨酶(alanine aminotransferase，ALT)及天冬氨酸转氨酶(aspartate aminotransferase，AST)水平，提取小鼠肝脏总RNA，经反转录用Cy3-dUTP和Cy5-dUTP分别标记制备cDNA探针。将cDNA探针与BiostarM-40S小鼠基因表达谱芯片进行杂交，经ScanArray 4000扫描仪扫描芯片并用GenePix Pro 3.0软件进行分析。双环醇可显著抑制刀豆蛋白A引起的血清ALT和AST升高。与刀豆蛋白A对照组相比，双环醇给药组有287条基因发生差异表达，占芯片基因总数的7.00%。其中166条基因表达量明显下调，121条基因表达量明显上调。表达变化的基因主要涉及代谢与细胞色素P450、应激与炎症凋亡、细胞周期调控、信号传导以及再生等相关功能。双环醇对刀豆蛋白A引起小鼠肝损伤肝脏基因表达谱变化具有一定的影响，此结果对今后深入研究双环醇的肝脏保护作用特点和临床应用具有重要意义。     

姜黄素保护刀豆蛋白A诱导的小鼠肝损伤作用的研究

目的：研究姜黄素（curcumin,Cur）对刀豆蛋白A（concanavalin A,Con A）诱导的小鼠肝损伤的保护作用及可能机制。方法：40只ICR小鼠被随机均分为正常对照组、模型组、Cur100 mg/kg组和200 mg/kg组。受试物组每天灌胃姜黄素液,模型组和正常对照组每天灌胃同体积生理盐水,连续10 d。末次给药后4 h,除正常对照组外均采用尾静脉注射Con A 20 mg/kg,8 h后检测被测试动物肝匀浆液的丙二醛（MDA）和超氧化物歧化酶（SOD）指标及血清ALT、AST指标,观察肝组织病理学改变。结果：与模型组相比,受试物组ALT、AST活力均显著降低,肝脏MDA水平降低,SOD活力提高,肝组织病理改变减轻。结论：姜黄素具有减轻肝损伤的作用,该作用可能通过减轻肝脏的氧化应激损伤来实现。     

刀豆蛋白A诱导急性肝损伤的模型建立

目的 建立刀豆蛋白A诱导急性肝损伤模型.方法 BLAB/c鼠69只,随机分为5组.A组尾静脉穿刺注射刀豆蛋白A 15 mg/kg,B、C、D组在尾静脉穿刺注射刀豆蛋白A前30 min分别注射肿瘤坏死因子α(TNF-α)和(或)γ干扰素(IFN-γ)抗体20 μg/只,E组注射等量生理盐水.分别在第4、8、12小时,采眼眶血,ELISA法检测TNF-α,IFN-γ,并留取肝组织行HE染色计算炎症活动度;取第12小时的肝组织行Western blot测定白细胞介素18(IL-18).结果 各组实验结束时非正常死亡数:A组6只,B组2只,C组3只,D组1只,E组0只.HE染色显示A组第4小时时可见大块坏死,碎屑样坏死等病变,B、C、D组炎症和坏死明显减轻(P<0.05).A组TNF-α、IFN-γ明显增高,而B、C、D组表达下降.A组IL-18呈强阳性.结论 刀豆蛋白A成功诱导了急性肝损伤模型,模型的形成与TNF-α、IFN-γ和IL-18有关,TNF-α、IFN-γ抗体可以阻断模型的建立.     

褐藻胶寡糖对刀豆蛋白A诱导的急性肝损伤保护作用及机制初探

目的 研究褐藻胶寡糖对刀豆蛋白A (Concanavalin A, ConA)诱导急性肝损伤的保护作用及其可能的作用机制。方法 本实验以分子量为3kDa的甘露糖醛酸寡糖（M-3k）和古罗糖醛酸寡糖（G-3k）为受试样品,通过检测ConA注射后14h血清转氨酶水平及肝组织病理学评估肝脏损伤;通过酶联免疫法(ELISA) 检测TNF-α、IL-6水平;Western Blotting法检测Bcl-2、Bax蛋白表达。结果 与模型组相比,褐藻胶寡糖预防组显著降低了ConA急性肝损伤小鼠血清AST和ALT水平(P＜0.05),且组织病理学观察发现,肝细胞损伤、炎性浸润和凋亡程度减轻;与模型组相比,褐藻胶寡糖预防组显著降低了肝组织匀浆中促炎因子TNF-α、IL-6水平(P＜0.05);褐藻胶寡糖预防组Bcl-2蛋白表达明显高于模型组(P＜0.05),Bax蛋白表达水平明显低于模型组(P＜0.05)。讨论 说明褐藻胶寡糖对ConA诱导小鼠急性肝损伤具有一定保护作用,并且其作用机制可能部分与抑制肝脏炎症反应和干扰凋亡过程有关。     

双氢青蒿素保护刀豆蛋白A诱导的小鼠肝损伤及机制探讨

目的研究双氢青蒿素(dihydroqinghaosu,DQHS)对刀豆蛋白A(concanavalin A,ConA)诱导的小鼠免疫性肝损伤的保护作用及可能机制。方法小鼠尾静脉注射ConA建立肝损伤模型;改良赖式法和ELISA法分别测定DQHS预给药对该模型小鼠血浆转氨酶和TNF-α水平的影响;MTT法检测DQHS对ConA诱导体外小鼠脾淋巴细胞增殖的影响;RT-PCR检测DQHS对LPS刺激的RAW264.7巨噬细胞IL-1β和TNF-αmRNA表达水平的影响。结果与模型组比较,DQHS 40μg.g-1给药组可降低ConA诱导的肝损伤小鼠血浆转氨酶水平,各DQHS组均可降低该小鼠血浆TNF-α水平;DQHS 40μmol.L-1和100μmol.L-1处理组能抑制ConA诱导的体外脾淋巴细胞增殖,减少LPS刺激的巨噬细胞炎症因子IL-1β和TNF-αmRNA的表达。结论DQHS对ConA诱导的小鼠免疫性肝损伤有保护作用,该作用可能通过抑制脾淋巴细胞增殖和巨噬细胞相关炎症细胞因子表达来实现。     

马栗种子提取物通过抑制活性氧及JNK途径保护刀豆蛋白A诱导的小鼠急性肝损伤

目的观察马栗种子提取物(AH)对刀豆蛋白A(Con A)诱导的小鼠急性肝损伤的保护作用,并探讨其相关机制是否与AH抑制氧化应激及其介导的c-Jun氨基末端激酶(JNK)途径有关。方法小鼠尾静脉一次性注射Con A(20mg·kg~(-1))制备急性肝损伤模型,AH保护组分别给予12.5、25、50 mg·kg~(-1)AH连续灌胃20 d预保护;全自动生化分析仪检测血清ALT、AST、TP、Alb、A/G;ELISA法检测小鼠血清IFN-γ、TNF-α水平;肝组织HE染色并进行病理学损伤分级评估;试剂盒检测肝组织MDA、SOD、GSH水平;分光光度法检测caspase-3活性;Western blot检测caspase-3、Bax、Bcl-2、p-JNK、p-Akt的蛋白表达情况。结果与Con A模型组相比,不同浓度的AH处理组小鼠血清ALT、AST、IFN-γ、TNF-α水平明显降低,TP、Alb、A/G比明显增高;肝组织的MDA水平明显降低,SOD、GSH水平明显升高。肝组织病理学与血清学指标改变相一致,AH处理组相比Con A模型组病理损伤明显减轻,病理损伤分级降低;与模型组相比,AH保护组细胞色素C、caspase-3、Bax/Bcl-2、p-JNK均明显降低,而pAkt蛋白表达升高。结论 AH可明显改善Con A诱导的小鼠急性肝损伤,其机制与AH抗氧化应激,进而抑制JNK/线粒体凋亡途径有关。     

IL-18及IL-18抗体对刀豆蛋白A所致急性肝损伤的作用

目的 探讨白细胞介素18(IL-18)及IL-18抗体对刀豆蛋白A所致急性肝损伤的预防作用及机理.方法 昆明小鼠57只,随机分为:正常对照组、兔IgG组、刀豆蛋白A组和IL-18及IL-18抗体组,尾静脉分别注射生理盐水、兔IgG、刀豆蛋白A、IL-18及IL-18抗体.在第4、8、12h,采用眼眶采血法,留取血清,ELISA法检测肿瘤坏死因子-α(TNF-α),干扰素因子-γ(IFN-γ),并留取肝组织行HE染色计算炎症活动度.结果 各组实验结束时,非正常死亡数各组比较有显著性差异(P＜0.05).炎症活动度评分与同期IL-18组和刀豆蛋白A组比较有显著性差异(P＜0.05).TNF-α、IFN-γ的检测也显示IL-18组明显增高,而予IL-18抗体干扰的小鼠血清TNF-α、IFN-γ表达下降.结论 IL-18可以增强刀豆蛋白A诱导的急性肝损伤的炎症作用,而IL-18抗体可以阻断这种作用.其机理可能是通过上调和抑制TNF-α、IFN-γ的表达.     

Caspase抑制剂F1013对刀豆蛋白A诱导小鼠急性肝损伤的治疗作用

目的研究Caspase抑制剂F1013对刀豆蛋白A(Co-nA)所致小鼠急性肝损伤模型的治疗作用,并对其机制进行初步探讨。方法 60只♂BALB/c小鼠随机分成对照组、模型组、阳性药组(NAC 155 mg.kg-1)和F1013(5,2.5,1.25 mg.kg-1)给药组。除对照组外,其余组小鼠均尾静脉注射ConA建立小鼠急性肝损伤模型,造模后2 h,阳性药组腹腔注射NAC,F1013给药组和模型组分别皮下注射F1013和溶媒。造模后8 h留取血清检测丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、总胆红素(T-Bil)含量和TNF-α水平,肝组织进行HE染色,并检测肝细胞凋亡率。结果在Co-nA诱导小鼠急性肝损伤模型,F1013组均明显改善肝脏病理组织损伤;明显降低血清ALT、AST、T-Bil和TNF-α水平及肝细胞凋亡率(P<0.01或P<0.05)。结论 F1013对Co-nA所致小鼠急性肝损伤具有较好的治疗作用,其机制可能与减少TNF-α的产生及抗肝细胞凋亡有关。     

葛根总黄酮对刀豆蛋白A诱导的小鼠免疫性肝损伤保护作用及其机制的初步研究

<正>病毒性肝炎(viral hepatitis)是常见病、多发病,通过一系列的免疫应答可引起肝细胞损伤,其中以细胞免疫为主,特别是TNF-α大量释放,可导致肝脏急性出血性坏死[1]。葛根是豆科植物野葛Pueraria lobata(Willd.)Ohwi.的干燥根,含多种黄酮类成分,具有解酒毒、降血脂等多种药理活性[2]。     

后适应对大鼠脑缺血-再灌注损伤线粒体结构和功能的影响

目的观察后适应对大鼠脑缺血-再灌注损伤线粒体结构和功能的影响。方法雄性SD大鼠随机分为假手术组、缺血-再灌注模型组(MCAO)、MCAO 预适应组、MCAO 后适应组和MCAO 尼莫地平组。大鼠脑缺血-再灌注24 h后,取脑进行TUNEL染色,免疫组织化学检察Bcl-2,Bax,Casepase-3和p53的蛋白表达,测定大鼠脑组织线粒体肿胀度、膜流动性、膜磷脂(PL)和丙二醛(MDA)含量、测定线粒体Na -K -ATP酶、Ca2 -ATP酶和超氧化物歧化酶(SOD)活性,并观察线粒体超微结构的改变。结果脑缺血-再灌注后半暗带线粒体的MDA含量明显增高,PL含量减少,膜脂流动性降低;ATP含量及Na -K -ATP酶、Ca2 -ATP酶、SOD活性明显降低。与MCAO组比较,后适应组大鼠凋亡细胞和Bax、Casepase-3、p53蛋白表达明显减少,ATP含量及Na -K -ATP酶、Ca2 -ATP酶、SOD活性明显升高。MCAO组大鼠脑线粒体肿胀,线粒体嵴断裂、溶解和消失,后适应明显减少缺血-再灌注引起的线粒体损伤程度。结论后适应对MCAO大鼠脑和线粒体的保护作用可能与其减少神经原凋亡,抑制p53、Bax、casepase-3表达,增加线粒体Na -K -ATPase、Ca2 -ATPase、SOD活性有关。     

水飞蓟素对伴刀豆球蛋白A致免疫性肝损伤小鼠的保护作用

目的研究水飞蓟素对伴刀豆球蛋白A(concanavalin A,Con A)诱导的免疫性肝损伤小鼠的保护作用,探讨其可能的肝保护机制。方法将实验小鼠30只随机分为对照组、模型组、水飞蓟素组(200 mg·kg~(-1)),各10只。对照组和模型组小鼠按10 m L·kg~(-1)灌胃0.5%羧甲基纤维素钠(CMC-Na)水溶液,水飞蓟素组小鼠灌胃同等容量的水飞蓟素(200 mg·kg~(-1),0.5%CMC-Na混悬),每日1次,共10 d。实验末期,模型组和水飞蓟素组小鼠尾静脉注射Con A(15 mg·kg~(-1))建立小鼠免疫性肝损伤模型,检测小鼠血清丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、碱性磷酸酶(ALP)活性及肝组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、还原型谷胱甘肽(GSH)、丙二醛(MDA)含量;苏木精-伊红(HE)染色法观察肝组织病理学变化。ELISA法检测血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-4(IL-4)和白细胞介素-6(IL-6)含量。结果水飞蓟素明显降低Con A所致免疫性肝损伤小鼠血清ALT、AST和ALP水平(P<0.01),还可增加肝组织SOD、CAT、GSH的活性,降低肝组织MDA水平(P<0.05或P<0.01),明显改善肝脏病理组织状况;显著降低小鼠血清TNF-α、IL-4和IL-6含量(P<0.01)。结论水飞蓟素能明显减轻Con A诱导的小鼠免疫性肝损伤,该作用与其增加肝组织中抗氧化酶的活性、降低脂质过氧化水平、降低TNF-α、IL-4和IL-6等促炎因子水平有关。     

S-Propargyl-cysteine prevents concanavalin A-induced immunological liver injury in mice

ContextS-Propargyl-cysteine (SPRC), an endogenous H₂S modulator, exerts anti-inflammatory effects on cardiovascular and neurodegenerative disease, but it remains unknown whether SPRC can prevent autoimmune hepatitis.ObjectiveTo evaluate the preventive effect of SPRC on concanavalin A (Con A)-induced liver injury and uncover the underlying mechanisms.Materials and methodsMice were randomly divided into five groups: control, Con A, SPRC (5 and 10 mg/kg injected intravenously once a day for 7 days), and propargylglycine (PAG; 50 mg/kg injected intraperitoneally 0.5 h before SPRC for 7 days). All mice except the controls were intravenously injected with Con A (20 mg/kg) on day 7. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using kits. Inflammatory cytokines (TNF-α and IFN-γ) in the blood and in the liver were detected by ELISA Kit and real-time PCR, respectively. The expression of mitogen-activated protein kinase (MAPK) pathway proteins (p-JNK and p-Akt) and apoptosis proteins (Bax and Bcl-2) was detected using western blotting.ResultsSPRC reduced the levels of AST (p < 0.05) and ALT (p < 0.01) and decreased the release of the inflammatory cytokines. Mechanistically, SPRC increased H₂S level (p < 0.05) and promoted cystathionine γ-lyase (CSE) expression (p < 0.05). SPRC inhibited the MAPK pathway activation and the apoptosis pathway. All the effects of SPRC were blocked by the CSE inhibitor PAG.ConclusionsSPRC prevents Con A-induced liver injury in mice by promoting CSE expression and producing endogenous H₂S. The mechanisms include reducing the release of inflammatory cytokines, attenuating MAPK pathway activation, and alleviating apoptosis.     

Effect of garlic-derived organosulfur compounds on mitochondrial function and integrity in isolated mouse liver mitochondria

The objectives of this work were to evaluate the direct effects of diallysulfide (DAS) and diallyldisulfide (DADS), two major organosulfur compounds of garlic oil, on mitochondrial function and integrity, by using isolated mouse liver mitochondria in a cell-free system. DADS produced concentration-dependent mitochondrial swelling over the range 125–1000 μM, while DAS was ineffective. Swelling experiments performed with de-energized or energized mitochondria showed similar maximal swelling amplitudes. Cyclosporin A (1 μM), or ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA, 1 mM) were ineffective in inhibiting DADS-induced mitochondrial swelling. DADS produced a minor (12%) decrease in mitochondrial membrane protein thiols, but did not induce clustering of mitochondrial membrane proteins. Incubation of mitochondria with DADS (but not DAS) produced an increase in the oxidation rate of 2′,7′ dichlorofluorescein diacetate (DCFH-DA), together with depletion of reduced glutathione (GSH) and increased lipid peroxidation. DADS (but not DAS) produced a concentration-dependent dissipation of the mitochondrial membrane potential, but did not induce cytochrome c release. DADS-dependent effects, including mitochondrial swelling, DCFH-DA oxidation, lipid peroxidation and loss of mitochondrial membrane potential, were inhibited by antioxidants and iron chelators. These results suggest that DADS causes direct impairment of mitochondrial function as the result of oxidation of the membrane lipid phase initiated by the GSH- and iron-dependent generation of oxidants.     

Angelica sinensis polysaccharide attenuates concanavalin A-induced liver injury in mice

Angelica sinensis polysaccharide (ASP), extracted from the roots of A. sinensis (Oliv.) Diels, is a β-d-pyranoid polysaccharide with an average molecular weight of 72,900 Da. In this study, we investigated the protective effects of ASP against concanavalin A-induced liver failure and the underlying mechanisms. Concentrations of ASP ranging from 5 to 125 μg/mL could inhibit concanavalin A (ConA)-induced lymphoproliferative response. The potential hepatoprotective activity of ASP was demonstrated by the significant decrease in serum transaminase (ALT and AST) levels and the attenuation of liver inflammation damage exhibited by H&E stain of the liver. Furthermore, ASP pretreatment significantly decreased proinflammatory cytokines (TNF-α, IFN-γ, IL-2 and IL-6) and alleviated oxidative stress by reducing MDA and ROS levels and by enhancing SOD activity after ConA administration in mice. Results of Western blot analysis indicated that ASP attenuated Caspase-3-dependent apoptosis by Caspase-8 and JNK-mediated pathway and inhibited the activation of IL-6/STAT3 and NF-κB signaling pathways in ConA-induced liver damage in mice. In conclusion, ASP pretreatment could attenuate concanavalin A-induced liver injury through its anti-inflammatory and anti-oxidant actions in mice.     

d-儿茶精对乙醇中毒小鼠肝线粒体急性损伤的影响

本文探讨d-儿茶精对乙醇诱导鼠肝线粒体急性损伤的修复作用。结果证实:该化合物降低模型动物肝线粒体膜脂质膜流动性,增加肝线粒体GSH含量,减少Ca~(2+)的摄取和脂质过氧化物生成。通过对抗乙醇的毒素作用缓解了肝线粒体膜结构的急性损伤。     

头顶一颗珠水提取物对非酒精性脂肪肝大鼠肝脏结构及功能的影响

目的：探讨头顶一颗珠对非酒精性脂肪肝（NAFLD）大鼠肝脏结构及功能的影响,阐明头顶一颗珠干预NAFLD的作用机制。方法：采用复合高脂饮食结合四氯化碳溶液腹腔注射建立NAFLD大鼠模型,模型复制成功后动物随机分为正常组、模型组、头顶一颗珠水提取物高、中、低剂量组、多烯磷脂酰胆碱组,连续灌胃给药4周,实验前及实验过程中每周称取大鼠体质量1次,实验结束称取肝湿重,计算肝指数,并观察动物肝脏的质地弹性及颜色、形态等,全自动生化分析仪测定肝酶谱,HE染色行大鼠肝脏病理组织学观察,免疫组化（SP）法检测GRP94蛋白表达,RT-PCR（逆转录聚合酶链反应）法检测GRP94 mRNA基因表达。结果：与正常组比较,模型组大鼠肝脏形态,光镜下结构,体质量、肝湿重和肝指数,肝酶谱,内质网应激等相关指标有显著异常的变化;与模型组比较,头顶一颗珠水提取物各剂量组大鼠肝脏肉眼形态,肝脏病理组织学不同程度改善,ALT、AST、ALP等肝酶谱指标及肝组织GRP94蛋白及基因表达不同程度下降,差异均有统计学意义（P<0.05或P<0.01）;结论：头顶一颗珠水提取物治疗NAFLD疗效明显,可有效逆转肝损伤,从多个层次防治NAFLD。     

A study of the effects of indometacin on liver mitochondria from rats, mice and humans

BACKGROUND: A part of the mechanism of the gastrointestinal toxicity exhibited by non-steroidal anti-inflammatory drugs is believed to involve the uncoupling of mitochondrial oxidative phosphorylation. Most previous uncoupling studies have used rat liver mitochondria. There is little information on the effects of the drugs on mitochondria from other species. AIM: To study the effect of indometacin on isolated liver mitochondria from rats, mice and humans. METHODS: We studied the effects of indometacin on respiration and adenosine triphosphate synthesis by isolated liver mitochondria from rats, mice and humans. Its effects were compared with those of dinitrophenol, a classical uncoupler. RESULTS: Indometacin uncoupled oxidative phosphorylation at low concentrations (P < 0.05) and inhibited respiration at high concentrations (P < 0.01) in all three species. Adenosine triphosphate synthesis was, however, more sensitive to dinitrophenol or indometacin at lower concentrations in mouse and human compared to rat liver mitochondria (P < 0.05). CONCLUSIONS: The current study shows that indometacin acts as an inhibitory uncoupler in human mitochondria. It also demonstrates that the responses of rat, mouse and human mitochondria to indometacin are broadly similar.