日本血吸虫病肝纤维化小鼠肝脏CTGF、TGFβ_1-mRNA的表达及意义

目的研究结缔组织生长因子(connective tissue growth factor,CTGF)mRNA与转化生长因子-β1(transforminggrowth factor-beta1,TGFβ-1)mRNA在日本血吸虫病肝纤维化小鼠肝脏中的表达及意义。方法用昆明小鼠感染尾蚴复制小鼠日本血吸虫病肝纤维化模型,模型组分别在6、10、14、18周杀鼠,治疗组在6周时予吡喹酮治疗后10、14、18周杀鼠;masson染色并图像分析进行胶原半定量;RT-PCR检测小鼠肝脏CTGFmRNA、TGFβ-1mRNA表达。结果模型组10周时小鼠血吸虫病肝纤维化形成,胶原量进行性增加,肝脏CTGFmRNA表达达高峰,10周、14周、18周时与治疗组相比均有明显的统计学差异(P均<0.01);模型组TGFβ-1mRNA表达水平和CTGFmRNA有相同的变化趋势,但18周时与治疗组已无明显差别(P>0.05);模型组CTGFmRNA和TGF-β1mRNA的表达具有直线相关性。结论CTGF与TGF-β1的基因表达与小鼠日本血吸虫病肝纤维化形成有密切关系;TGF-β1的致纤维化作用可能部分通过CTGF的生物学作用介导;通过阻断CTGF的传导通路可能是肝纤维化治疗的有效靶点。     

罗格列酮对非酒精性脂肪性肝炎大鼠肝组织Kruppule样因子6信号通路的影响

目的观察罗格列酮对NASH肝纤维化大鼠肝组织kruppule样因子（KLF）6及其下游靶基因TGFβ1信号通路的影响。方法36只雄性Wistar大鼠随机分为对照组、高脂组和罗格列酮组,24周末处死所有大鼠,留取肝组织行HE和Massson染色,检测血清TG、游离脂肪酸、AST、ALT及HA、LN、CⅣ等,RT-PCR检测核转录因子KLF6、TGFβ1以及反映HSC活化的特异性标记α-平滑肌肌动蛋白（α-SMA）mRNA的变化,免疫组织化学检测KLF6、过氧化物酶体增殖物激活受体γ、α-SMA的蛋白表达。结果模型组大鼠24周末出现典型脂肪性肝纤维化,治疗组纤维化程度明显减轻和改善。模型组血清生物化学指标及肝纤维化指标均有不同程度增高,罗格列酮干预16周后上述各指标均见明显改善,两组间差异有统计学意义（P〈0.01）。RT-PCR显示模型组KLF6 mRNA（0.96±0.08）、TGFβ1 mRNA（0.91±0.07）和α-SMA mRNA （1.08±0.19）的相对表达量均明显上升,与对照组比较差异有统计学意义（P〈0.01）;治疗组则显示增高的上述基因呈不同程度的下降,差异有统计学意义（P〈0.01）。免疫组织化学显示罗格列酮组KLF6、α-SMA蛋白的表达较模型组减少,而PPARγ的表达较模型组增加,差异均有统计学意义（P〈0.05）。结论罗格列酮可以激活PPARγ,降低NASH肝纤维化大鼠肝组织核转录因子KLF6及其下游靶基因TGFβ1的表达,抑制HSC的活化,阻止肝纤维化形成,这可能是其发挥抗肝纤维化的作用之一。     

血红素加氧酶-1调控核转录因子-κB表达抑制非酒精性脂肪性肝纤维化的机制

目的探讨在非酒精性脂肪性肝纤维化进展中血红素加氧酶-1（HO-1）靶向激活对核转录因子-κB（NF-κB）、细胞间黏附分子-1（ICAM-1）及血小板源性生长因子（PDGF）表达的影响,以明确HO-1基因调控阻止该病发生发展的分子机制。方法选用清洁级7～8周龄健康雄性C57BL/6J小鼠,蛋氨酸-胆碱缺乏（MCD）饮食喂养8周建立非酒精性脂肪性肝纤维化模型,分别采用HO-1激动剂血晶素、抑制剂锌原卟啉进行干预实验,以蛋氨酸-胆碱充足饮食设立对照组。实时荧光定量PCR检测肝组织HO-1、NF-κB、ICAM-1和PDGF mRNA表达;Western Blot检测肝组织HO-1、PDGF蛋白表达。结果模型组伴随肝脂肪变、炎症及纤维化的形成,肝组织HO-1、NF-κB、ICAM-1和PDGF mRNA表达显著增强,HO-1、PDGF蛋白表达与mRNA表达趋势一致;应用血晶素组肝损伤明显改善,肝组织NF-κB、ICAM-1和PDGF表达显著下调,而应用锌原卟啉组则呈相反趋势。结论 HO-1靶向激活可通过抑制NF-κB、及其下游ICAM-1、及PDGF表达阻止非酒精性脂肪性肝纤维化的发生与进展。     

TGFβ1和CTGF在非酒精性脂肪性肝炎肝组织中的表达及意义

目的:探讨非酒精性脂肪性肝炎(NASH)患者肝脏转化生长因子β1(TGFβ1)和结缔组织生长因子(CTGF)的表达及二者在脂肪性纤维化发展过程中的相关性.方法:采用HE染色,光镜下观察21例非酒精性脂肪性肝炎组(NASH组)肝组织和10例正常肝组织组标本肝组织的病理改变;RT-PCR及免疫组织化学技术分别检测以上两组标本中TGFβ1和CTGF的表达情况.结果:光镜下非酒精性脂肪性肝炎组出现明显炎症反应和纤维化.免疫组化结果显示非酒精性脂肪性肝炎组肝脏TGFβ1和CTGF的表达显著高于正常肝脏组(109.52±4.50 VS 1 14.47±2.00,117.07±3.60 VS 125.05±3.37,均P＜0.01).NASH组TGFβ1和CTGF mRNA的表达水平升高明显,与对照组比较差异有统计学意义(0.66±0.07 VS 0.46±0.04,0.59±0.08VS 0.41±0.05,均P＜0.05).结论:TGFβ1和CTGF在非酒精性脂肪性肝炎中的表达升高可能参与了脂肪性肝炎向肝纤维化转变,CTGF可能在诊断和治疗非酒精性脂肪性肝炎中扮演重要的作用.     

壳脂胶囊对NASH小鼠肝组织血红素氧合酶-1表达的影响

目的观察壳脂胶囊对非酒精性脂肪性肝炎小鼠肝组织血红素氧合酶-1（HO-1）表达的影响。方法将C57 BL/6J小鼠20只随机分为对照组（采用蛋氨酸-胆碱充足饮食喂养）、模型组[给予高脂、蛋氨酸-胆碱缺乏（MCD）饮食喂养]、壳脂胶囊治疗组和自然恢复组。8周末检测血清转氨酶、瘦素水平,并观察肝组织脂肪变、炎症活动及纤维化程度;定量检测肝组织HO-1 mRNA的表达。结果治疗组动物肝脂肪变及炎症程度较模型组明显减轻,血清瘦素水平和肝组织HO-1表达较模型组明显降低（P〈0.05）。结论在高脂、胆碱-蛋氨酸缺乏饮食诱导的NASH小鼠,壳脂胶囊可降低肝组织HO-1表达,阻止NASH的发生发展。     

日本血吸虫病小鼠肝纤维化肝脏CTGF、TGF-β1的表达及意义

目的 研究结缔组织生长因子（connective tissue growth factor，CTGF）与转化生长因子β1（transforming growth factor-betal，TGF-β1）在日本血吸虫病小鼠肝纤维化肝脏中的表达状况及意义。方法 用昆明小鼠感染尾蚴建立日本血吸虫病小鼠肝纤维化模型，随机分为模型组和对照组，感染后6、10、14、18周杀鼠；HE染色观察肝脏病理变化，免疫组化法检测肝内CTGF、TGF-β1蛋白的表达水平。结果 模型组小鼠10周时形成血吸虫病肝纤维化，此时肝内CTGF表达达高峰。且10、14、18周时的表达量均显著高于同期对照组（P〈0．01）；模型组TGF-β1蛋白定量和CT—GF有相同的变化趋势，但18周时与同期对照组比较差异无显著性（P〉0．05）；模型组CTGF和TGF-β1蛋白表达水平具有直线相关性。结论 CTGF与TGF-β1的表达与日木血吸虫病小鼠肝纤维化形成有密切关系，TGF-β1的致纤维化作用可能部分通过CTGF的生物学作用介导，阻断CTGF的传导通路可能是血吸虫病肝纤维化治疗的有效靶点。     

罗格列酮对非酒精性脂肪性肝炎小鼠肝组织过氧化物酶体增殖物激活受体γ mRNA及其蛋白表达的影响

目的 探讨过氧化物酶体增殖物激活受体γ(pemxisome pmliforator-activated receptor gamma,PPARγ)激动剂罗格列酮对非酒精性脂肪性肝炎(non-alcoholic steatohepatitis,NASH)小鼠肝组织PPARγ mRNA及其蛋白表达的影响及其在NASH进展中的作用.方法 健康雄性C57BL/6J小鼠15只,随机分为对照组、模型组和罗格列酮干预组.酶法检测小鼠血清丙氨酸氨基转移酶(ALT)和甘油三酯(TG)水平;光镜下观察肝组织脂肪变程度、炎症活动度和纤维化程度;采用RT-PCR和Western印迹法检测PPARγ和TNF-a mRNA及其蛋白的表达.结果 对照组小鼠肝脏未出现明显的脂肪变、炎症和纤维化,而模型组肝脂肪变及炎症明显,罗格列酮干预组肝脂肪变及炎症均明显减轻.罗格列酮干预组、模型组和对照组肝组织PPARγ mRNA及其蛋白表达依次为0.83±0.01、0.75±0.01、0.72±0.01和0.77±0.00、0.69±0.02、/0.49±0.01(P＜0.01).模型组、罗格列酮干预组、对照组TNF-a mRNA及蛋白表达依次为1.11±0.01、0.99±0.02、0.91±0.00和0.99±0.01、0.60±0.01、0.47±0.01(P＜0.01).结论 在高脂、胆碱一蛋氨酸缺乏饮食诱导的小鼠NASH模型中,肝组织TNF-α活性与NASH的进展有关;PPARγ特异性激动剂罗格列酮可通过上调PPARγ水平而抑制TNF-α表达,进一步阻止NASH的进展,为NASH的靶向性治疗药物的选择提供了新思路.     

罗格列酮对血吸虫病肝纤维化小鼠肝脏TGF-β1和α-SMA表达的影响

目的 研究过氧化物酶体增殖物激活受体γ (PPARγ)的配体罗格列酮对日本血吸虫病肝纤维化小鼠肝脏转化生长因子β1(TGF-β1)、α-平滑肌肌动蛋白(α-SMA)含量的影响.方法 将30只日本血吸虫病肝纤维化小鼠均分3组对照组,吡喹酮治疗组和罗格列酮治疗组.对照组不作任何治疗.吡喹酮治疗组用吡喹酮500 mg/(kg·d)灌胃治疗2 d,罗格列酮治疗组在吡喹酮治疗2 d后再用罗格列酮4 mg/(Kg·d)灌胃治疗6周.应用HE染色,免疫组化法及多媒体病理图文定量分析,观察罗格列酮治疗血吸虫病肝纤维化小鼠肝脏的病理改变及TGF-β1和α-SMA表达的变化.结果 罗格列酮能显著抑制血吸虫病小鼠肝脏纤维组织的增生,降低肝脏TGF-β1及α-SMA的表达.结论 PPARγ配体罗格列酮有明显的抗日本血吸虫病肝纤维化作用,其抗纤维化机制与其抑制肝星状细胞(HSC)活化、抑制其表达α-SMA及分泌TGF-β1密切相关.     

PPAR γ配体罗格列酮对血吸虫病肝纤维化小鼠血清TNF-α和IL-6的影响

目的：检测过氧化物酶体增殖物激活受体γ（PPARγ）配体罗格列酮治疗血吸虫病肝纤维化小鼠血清TNF-α和IL-6水平的变化及意义。方法：建立血吸虫病肝纤维化小鼠模型，应用PPARγ的配体罗格列酮治疗并应用放射免疫法检测血吸虫病肝纤维化小鼠血清TNF-α和IL-6水平的变化。结果：罗格列酮治疗可显著降低肝纤维化小鼠血清TNF-α和IL-6含量，与感染对照组及吡喹酮治疗组比较差异有显著性意义（P〈0．05）。结论：罗格列酮可明显降低血吸虫病肝纤维化小鼠TNF-α和IL-6水平，从而发挥其抗肝纤维化的作用。     

改良蛋氨酸胆碱缺乏饮食喂养的非酒精性脂肪性肝炎大鼠模型的建立

目的:观察改良蛋氨酸胆碱缺乏饮食(MCD)建立的脂肪性肝炎大鼠模型肝脏的脂肪变性和炎症情况.方法:大鼠26只随机分为4组,分别喂养MCD饮食和胆碱添加饮食(CS).3-8wk后处死,肝脏标本在甲醛中固定和石蜡包埋.HE染色和Masson染色后对脂肪变性、炎症和纤维化进行评分.血清ALT,AST,CH,LDL等指标通过生化分析仪进行测定.结果:MCD喂养组3wk可以看见肝脂肪变性和炎症,肝指数显著增加,ALT和AST显著升高,8wk可见纤维形成.结论:可通过改良的蛋氨酸胆碱缺乏(MCD)饮食建立非酒精性脂肪肝动物模型.     

Rosiglitazone prevents nutritional fibrosis and steatohepatitis in mice

Objective. Currently, no agent has been confirmed as preventing the fibrosing progression of non-alcoholic steatohepatitis (NASH). In this study, rosiglitazone was used in the clinical treatment of insulin resistance in patients with type 2 diabetes mellitus. However, its protective effect on non-alchoholic fibrosing steatohepatitis is not clear. The study aimed to elucidate the effect and the mechanism of rosiglitazone in inhibiting nutrition-related fibrosis in mice. Methods. C57BL6/J mice were fed a high fat, methionine-choline deficient (MCD) diet for 8 weeks to induce hepatic fibrosis, and rosiglitazone was given in the treated group. The effect of rosiglitazone was assessed by comparing the severity of hepatic fibrosis in liver sections, the activation of hepatic stellate cells (HSCs) and the expression of TGF-β1 and connective tissue growth factor (CTGF). Results. At week 8, MCD-diet-induced fibrosing NASH models showed increased serum ALT and AST levels, severe hepatic steatosis, and infiltration of inflammation and fibrosis which, associated with down-regulated PPARγ mRNA and protein expression, up-regulated α-SMA protein expression and enhanced TGF-β1, CTGF mRNA and protein expression. Rosiglitazone significantly lowered serum ALT and AST and it reduced MCD-induced fibrosis by repressing levels of α-SMA protein expression and pro-fibrosis factors TGF-β1 and CTGF. It also restored expression of PPARγ. Conclusions. The present study provides clear morphological and molecular biological evidence of the protective role of rosiglitazone in ameliorating nutritional fibrosing steatohepatitis. Rosiglitazone may ameliorate hepatic fibrosis by activating PPARγ, which can inhibit HSC activation and suppress TGF-β1 and CTGF expression.     

Fas基因突变在非酒精性脂肪性肝炎发病中的作用

目的 探讨Fas基因突变在非酒精性脂肪性肝炎发生、发展中的作用。方法 选用健康雄性野生型及Fas基因突变C57BL/6J小鼠,以高脂、胆碱-蛋氨酸缺乏饮食喂养3周建立小鼠非酒精性脂肪性肝炎模型,分别作为野生型小鼠模型组和Fas基因突变小鼠模型组,以胆碱-蛋氨酸充足饮食喂养两种小鼠分别设立野生型小鼠对照组和Fas基因突变小鼠对照组。检测血清ALT、AST、甘油三酯、总胆固醇水平;观察肝组织脂肪变、炎症活动及纤维化程度;用实时定量RT-PCR检测肝组织增殖细胞核抗原和转化生长因子β 1 mRNA的表达,免疫组织化学染色检测肝组织增殖细胞核抗原和转化生长因子β 1蛋白质表达情况。多组样本均数间差异比较用单因素方差分析,组间比较用LSD-t检验。结果 野生型小鼠模型组及Fas基因突变小鼠模型组血清ALT水平均较其对照组明显升高,分别为(126.33±10.50) U/L比(25.00±10.14) U/L、(160.33±48.29) U/L比(18.33±9.08) U/L,组间比较,t值分别为12.02、5.08,P值均＜0.01,差异均有统计学意义;两种模型组小鼠ALT水平比较,P＞0.05,差异无统计学意义;各组小鼠AST、甘油三酯、总胆固醇水平差异均无统计学意义（P值均＞0.05）。野生型小鼠模型组出现大泡性肝细胞脂肪变性,伴有点状和灶状肝细胞坏死、炎性细胞浸润、轻度汇管区纤维组织增生及窦周纤维化,肝组织增殖细胞核抗原、转化生长因子β 1 mRNA表达较对照组显著增强,相对表达量分别为2.84±0.73、2.77±0.54比1.31±0.18、0.89±0.18,组间比较,t值分别为4.99、8.08,P值均＜0.01,差异均有统计学意义;Fas基因突变小鼠模型组肝脂肪变及炎症、纤维化程度均较Fas基因突变小鼠对照组及野生型小鼠模型组明显加重,肝组织增殖细胞核抗原、转化生长因子p 1 mRNA表达较其对照组及野生型模型组显著增强,相对表达量分别为5.57±1.13比1.04±0.16、2.84±0.73和5.73±0.89比0.85±0.11、2.77±0.54,t值分别为10.15、5.33和13.19、6.91,P值均＜0.01 ;蛋白质表达变化趋势与mRNA变化一致。结论 Fas基因突变可诱导或加剧肝细胞损伤,促进非酒精性脂肪性肝炎的发生及进展。     

过氧化物酶体增殖物激活受体γ抗肝细胞凋亡的机制

目的 研究靶向调控过氧化物酶体增殖物激活受体γ(PPAR γ)的表达及活性在非酒精性脂肪性肝纤维化中抗肝细胞凋亡的作用及其机制.方法 用高脂、胆碱-蛋氨酸缺乏饮食(MCD)喂养小鼠8周,设立对照组:胆碱-蛋氨酸充足饮食;模型组:MCD喂养;PPAR γ激动剂组:用MCD加50mg·kg-1·d-1罗格列酮喂养; PPAR γ抑制剂组:用MCD喂养,腹腔注射PPAR γ抑制剂GW9662 1 mg/kg,每周3次; PPAR γ基因导入组:用MCD喂养,腹腔注射重组腺病毒质粒Ad-PPAR γ 1×1010 vp,每周3次;腺病毒空载体导入组:用MCD喂养,腹腔注射重组腺病毒质粒Ad-LacZ 1×1010 vp,每周3次; PPAR γ基因导入联合激动剂组;用MCD喂养,腹腔注射Ad-PPAR γ 1×1010 vp,每周3次,同时给予罗格列酮50 mg·kg-1·d-1.检测肝组织PPAR γ、Fas、Fas配体、B细胞淋巴瘤/白血病-2(Bcl-2)、Bcl-2相关X蛋白及天冬氨酸特异性半胱氨酸蛋白酶-3(caspase-3)mRNA及蛋白质表达.多组样本均数间差异比较用单因素方差分析,用LSD-t检验进行组间比较.结果 肝组织促凋亡基因Fas、Fas配体、Bcl-2相关X蛋白及caspase-3表达较对照组明显上调,mRNA相对表达量分别为3.59±0.35比1.11±0.37、4.37±1.03比1.09±0.33、4.27±0.48比1.03±0.10及4.93±0.67比1.12±0.24,两组比较,t值分别为2.49、3.28、3.25、3.80,P值均<0.01;蛋白质相对表达量分别为1.96±0.07比0.45±0.07、0.53±0.07比0.22±0.02、1.32±0.06比0.59±0.03及1.51±0.23比0.36±0.09,两组比较,t值分别为1.51、0.31、0.73、1.14,P值均<0.01.抑凋亡基因Bcl-2表达亦相应上调,mRNA相对表达量为3.95±0.34比1.20±0.19,两组比较,t=2.75,P<0.01,蛋白质相对表达量为0.57±0.01比0.29±0.01,两组比较,t=0.28,P<0.01.PPAR γ激动剂组Fas、Fas配体、Bcl-2相关X蛋白、caspase-3及Bcl-2 mRNA相对表达量分别为3.78±0.58、3.66±0.83、3.04±0.37、2.54±0.62、4.42±0.42,与模型组比较,t值分别为0.18、0.71、1.23、2.39、0.46,P值分别>0.05、>0.05、<0.01、<0.01、>0.05,蛋白质相对表达量分别为1.06±0.03、0.30±0.01、0.70±0.05、1.19±0.30、0.90±0.01,t值分别为0.90、0.23、0.62、0.31、0.34,P值分别<0.01、<0.01、<0.01、>0.05、<0.01;PPAR γ基因导入组mRNA相对表达量分别为2.31±0.16、2.71±0.23、2.52±0.27、1.79±0.32、5.97±0.72,与模型组比较,t值分别为1.28、1.66、1.75、3.13、2.02,P值均<0.05,蛋白质相对表达量分别为1.73±0.07、0.43±0.04、1.01±0.08、1.31±0.10、1.56±0.04,t值分别为0.23、0.10、0.30、0.20、0.99,P值分别<0.01、<0.01、<0.01、>0.05、<0.01.结论 PPAR γ靶向性激活和(或)PPAR γ基因导入可抑制促凋亡基因主导的信号转导通路激活,抑制肝细胞凋亡.

Abstract：

Objective To elucidate the effect of targeted gene modulation of peroxisome proliferator activated receptor gamma (PPAR γ) on hepatocellular apoptosis in nutritional fibrotic steatohepatitis in mice. Methods C57BL/6J mice were fed with high fat, methionine-choline deficient (MCD) diet for 8 weeks to induce fibrotic steatohepatitis. Mice fed the MCD diet were treated with adenovirus carrying PPAR γ (AdPPAR|(A)), adenovirus-beta-galactosidase (Ad-LacZ), Ad-PPAR γ plus PPAR γ agonist rosiglitazone, or PPAR γ antagonist 2-chloro-5-nitro- benzaniliden (GW9662), respectively. H&E stain was performed for observation of hepatocellular apoptosis, hepatic steatosis, inflammation and fibrosis in the liver sections. The expression levels of mRNA and protein of PPAR γ and apoptosis related genes, Fas, Fas Ligand (FasL), B celllymphoma/leukemia-2 (Bcl-2), Bcl-2 associated X protein (Bax) and cysteine-containing aspartate-specific proteases-3 (caspase-3) were detected by real-time RT-PCR and Western blot assay, respectively. Results Mice fed with MCD diet for 8 weeks showed severe hepatic injury including steatosis, hepatocellular apoptosis, inflammatory infiltration and fibrosis, concomitancy with enhanced expression of pro-apoptosis genes, Fas, FasL, Bax and caspase-3 and increased expression of anti-apoptosis gene Bcl-2, by comparing with the control group. The mRNA expression levels of these genes were 3.59 ± 0.35 vs 1.11 ± 0.37, 4.37 ± 1.03 vs 1.09 ± 0.33,4.27 ± 0.48 vs 1.03 ± 0.10, 4.93 ± 0.67 vs 1.12 ± 0.24 and 3.95 ± 0.34 vs 1.20 ± 0.19,and LSD-t values were 2.49, 3.28, 3.25, 3.80 and 2.75, as compared with the control group, P < 0.01; the protein expression levels were 1.96 ± 0.07 vs 0.45 ± 0.07, 0.53 ± 0.07 vs 0.22 ± 0.02, 1.32 ± 0.06 vs 0.59 ± 0.03,1.51 ± 0.23 vs 0.36 ± 0.09 and 0.57 ± 0.01 vs 0.29 ± 0.01, and LSD-t values were 1.51, 0.31, 0.73, 1.14 and 0.28, P < 0.01. Administration of PPAR γ agonist rosiglitazone and/or Ad-PPAR γ significantly ameliorated hepatic steatosis, hepatocellular apoptosis, necroinflammation and fibrosis. These effects were associated with repressed expression of pro-apoptosis genes and up-regulated expression of anti-apoptosis gene. After rosiglitazone treatment, the mRNA expression levels were 3.78 ± 0.58, 3.66 ± 0.83, 3.04 ± 0.37, 2.54 ± 0.62 and 4.42 ± 0.42, and LSD-t values were 0.18, 0.71, 1.23,2.39 and 0.46, as compared with MCD group, the P values were 0.627,0.241, <0.01, <0.01 and 0.278; the protein expression levels were 1.06 ± 0.03, 0.30 ± 0.01, 0.70 ± 0.05, 1.19 ± 0.30 and 0.90 ± 0.01, and LSD-t values were 0.90,0.23,0.62,0.31 and 0.34, the P values were <0.01, <0.01, <0.01,0.122, <0.01. After Ad-PPAR γ treatment, the mRNA expression levels were 2.31 ± 0.16, 2.71 ± 0.23, 2.52 ± 0.27, 1.79 ± 0.32 and 5.97 ± 0.72, and LSD-t values were 1.28, 1.66,1.75, 3.13 and 2.02, as compared with MCD group, P < 0.05; the protein expression levels were 1.73 ± 0.07, 0.43 ± 0.04, 1.01 ± 0.08, 1.31 ± 0.10 and 1.56 ± 0.04, and LSD-t values were 0.23,0.10,0.30,0.20 and 0.99, with P values equal 0.009,0.01, <0.01,0.322 and <0.01. Conclusions This study provided evidences for the protective role of activation and overexpression of PPAR γ in ameliorating hepatocellular apoptosis in mice with hepatic fibrosing steatohepatitis.     

血红素加氧酶-1在非酒精性脂肪性肝炎进展中的作用

目的 探讨血红素加氧酶-1(HO-1)在非洒精性脂肪性肝炎进展中的作用及其机制.方法 选用健康雄性C57BL/6J小鼠,采用胆碱-蛋氨酸缺乏饮食(MCD)4周建立小鼠非酒精性脂肪性肝炎模型,以胆碱-蛋氨酸充足饮食设立对照组,并以MCD加HO-1激动剂血晶素或抑制剂锌原卟啉进行干预实验.小鼠血清ALT和AST采用全自动生化仪酶法测定.HE染色观察肝脂肪变、炎症活动及纤维化程度;逆转录聚合酶链反应和Western blot检测HO-1、肿瘤坏死因子(TNF)α和白细胞介素(IL)-6 mRNA及其蛋白的表达.结果 MCD喂养小鼠血清ALT及AST明显异常,出现中～重度肝细胞脂肪变性,伴有点状和灶状肝细胞坏死、炎性细胞浸润、轻度汇管区纤维组织增生及窦周纤维化;HO-1、TNF α和IL-6 mRNA及其蛋白的表达较对照组显著增强,相对表达量分别为1.13±0.11、1.74±0.05,0.20±0.01、1.92±0.10,0.58±0.02、2.06±0.05对比0.43±0.02、0.75±0.05,0.08±0.00、0.59±0.02,0.22±0.01、0.91±0.02(P＜0.01);应用血晶素小鼠随肝脏HO-1 mRNA及其蛋白表达的上调及TNF α和IL-6 mRNA及其蛋白表达的下调(P＜0.01),肝脂肪变及炎症活动度均显著减轻;而应用锌原卟啉小鼠,肝脏HO-1 mRNA及蛋白表达明显受抑制,TNF α和IL-6 mRNA及蛋白表达则明显增强(P＜0.01),肝脂肪变及炎症亦随之显著加重.结论 抗氧化基因HO-1靶向性激活可阻止非酒精性脂肪性肝炎的发生及进展.     

壳脂胶囊对小鼠非酒精性脂肪性肝炎氧化应激的影响

目的 观察壳脂胶囊对小鼠非酒精性脂肪性肝炎(NASH)肝组织氧化应激及脂质过氧化反应的影响,探讨其对NASH的防治作用及机制.方法 健康雄性C57BL/6J小鼠18只,随机分为三组,每组6只.采用高脂、胆碱-蛋氨酸缺乏(MCD)饮食4周建立小鼠NASH模型,应用壳脂胶囊进行干预实验,并以胆碱-蛋氨酸充足饮食设立对照组....     

膜联蛋白I在大鼠肝纤维化组织中的表达及意义

目的检测膜联蛋白Ⅰ（AnnexinⅠ）、转化生长因子（TGF）β1、α–平滑肌肌动蛋白（α–SMA）在大鼠肝纤维化组织中的表达,阐明AnnexinⅠ在肝纤维化中的作用机制。方法雄性SD大鼠随机分为健康对照组6只,肝纤维化模型组24只,采用二甲基亚硝胺（DMN）腹腔注射制备肝纤维化模型。肝纤维化模型组2、4、6、8周各6只大鼠门静脉采血检测血清ALT、AST,采用HE及Masson染色观察肝组织学变化,应用反转录聚合酶链反应（RT–PCR）检测肝组织AnnexinⅠ、TGFβ1、α–SMA mRNA表达,Western Blot法检测肝组织AnnexinⅠ表达。结果与对照组比较,肝纤维化模型组血清ALT、AST水平随损伤时间延长逐渐升高,4周达高峰,6周下降,差异有统计学意义（P〈0.05）;正常肝组织有AnnexinⅠ、TGFβ1、αSMA低表达,2周即升高,4、6周较明显,8周下降,肝纤维化模型组与对照组在2、4、6、8周各时间点差异有统计学意义（P〈0.05）。结论 AnnexinⅠ对肝脏可能有保护作用,为临床肝纤维化的防治提供新策略     

复方牛胎肝提取物抑制小鼠转化生长因子β1/Smad2信号通路发挥抗纤维化的作用机制

目的研究复方牛胎肝提取物通过抑制肝纤维化小鼠肝脏组织转化生长因子β1/Smad 2通路发挥抗纤维化作用的机制。方法健康雄性ICR小鼠90只,随机分为正常对照组(10只),模型组(20只),治疗组(60只)。治疗组按不同剂量分为大剂量治疗组(20只),中剂量治疗组(20只),小剂量治疗组(20只)。模型组及治疗组皮下注射30%四氯化碳溶液制备肝纤维化小鼠模型。治疗组造模8周后用复方牛胎肝提取物以大、中、小剂量灌胃治疗,1次/d,持续4周;正常组及模型组同期予等量生理盐水灌胃。肝脏组织经HE染色后光学显微镜观察病理变化;采用Real-Time PCR、免疫组织化学及Western蛋白印迹法分别检测正常组、模型组及治疗组TGFβ1、蠕虫果蝇母抗同源蛋白(Smad)2的mRNA及蛋白表达水平。各组间均数比较采用单因素方差分析。方差齐性采用Levene法检验,样本均数比较采用单因素方差分析;方差不齐时采用秩和检验。相关性检验采用Pearson直线相关分析。结果正常对照组TGFβ1、Smad 2 mRNA及蛋白表达量很低,模型组较高,治疗组较模型组表达下降,大剂量治疗组下降最为显著,其他2组随治疗剂量的减少表达逐渐增加;各组TGFβ1、Smad 2 mRNA表达水平差异具有统计学意义(χ2=27.877、26.688,P0.05)。直线相关性分析显示:各治疗组TGFβ1、Smad 2的mRNA表达水平与治疗剂量均呈负相关(r=-0.967、-0.956,P0.05)。结论复方牛胎肝提取物能改善小鼠肝脏纤维化程度,并呈剂量依赖性抑制TGFβ1、Smad 2蛋白在肝纤维化组织中的表达,这可能与其抗肝纤维化机制相关。     

Isolated idiopathic bile ductular hyperplasia in patients with persistently abnormal liver function tests

BACKGROUND/AIMS: Feeding mice a methionine choline deficient (MCD) diet serves as a nutritional model of non-alcoholic steatohepatitis (NASH). NASH and alcohol-induced steatohepatitis are histologically similar, suggesting a similar pathogenesis. Pentoxifylline (PTX) attenuates TNF-alpha production, acts as an antioxidant and decreases mortality in alcoholic steatohepatitis. The aim of our study is to determine if PTX attenuates MCD diet induced steatohepatitis and determine the mechanism of this effect. METHODS: Mice were placed on an MCD or control diet for 2 weeks and were treated with or without PTX. Serum ALT, liver histology, and inflammatory mechanisms were evaluated. RESULTS: PTX attenuates MCD diet induced steatohepatitis, decreasing both serum ALT levels and hepatic inflammation. Serum ALT levels were reduced approximately 50% in the MCD+PTX group compared to the MCD group. Hepatic glutathione levels were significantly higher in the MCD+PTX group compared to the MCD group. There was also a reduction in TNF-alpha mRNA in female mice treated with PTX. MCD+PTX mice had increased hepatic triglyceride content compared to the MCD mice, but less histologic evidence of inflammation despite the increased steatosis. Serum lipid and bile salt levels also were similar in PTX and vehicle control treated mice. CONCLUSIONS: PTX decreases serum ALT levels and hepatic inflammation in the MCD model of steatohepatitis, likely via increasing glutathione levels or reducing TNF-alpha expression.     

Bezafibrate prevents hepatic stellate cell activation and fibrogenesis in a murine steatohepatitis model,and suppresses fibrogenic response induced by transforming growth factor‐β1 in a cultured stellate cell line

Aim: The aim of this study was to investigate the preventive actions of bezafibrate against non‐alcoholic steatohepatitis (NASH), the activation of hepatic stellate cells (HSC), and fibrogenesis by using a model of NASH and an in vitro model. Methods: Male KK‐A^y/TaJcl (KK‐A^y) mice were fed a methionine and choline‐deficient (MCD) diet or a MCD diet containing bezafibrate or pioglitazone for 7 weeks, after which biochemical parameters, pathological changes, and hepatic mRNA levels were assessed. An in vitro HSC model was designed by using a previously described RI‐T cell line stimulated by transforming growth factor‐β1 (TGF‐β1). Results: MCD diet‐fed KK‐A^y mice developed hepatic steatosis, oxidative stress, inflammation, and hepatic fibrosis. Bezafibrate markedly decreased the hepatic content of triglyceride accumulation of fatty droplets within hepatocytes, and increased the expression of hepatic fatty acid β‐oxidative genes in MCD diet‐fed KK‐A^y mice. Bezafibrate markedly inhibited the increases in the plasma alanine aminotransferase level and hepatic content of thiobarbituric acid‐reactive substances in this model. Moreover, it dramatically reduced hepatic inflammatory changes and fibrosis concomitantly with marked reductions in the mRNA levels for inflammatory cytokine, chemokine, and profibrogenic genes. Importantly, both bezafibrate and pioglitazone markedly reduced the mRNA levels of profibrogenic and fibrogenic genes in TGF‐β1‐stimulated cells. Conclusion: Bezafibrate improved hepatic steatosis and potently prevented inflammation, oxidative stress, HSC activation, and fibrogenesis in the liver. Moreover, this study was the first to demonstrate that bezafibrate directly inhibits hepatic fibrogenic response induced by TGF‐β1 in vitro. Hence bezafibrate may be a new therapeutic strategy against NASH and hepatic fibrosis.