吲哚美辛对刀豆蛋白A诱导小鼠急性肝损伤的保护作用

吲哚美辛（消炎痛）预处理能诱导大鼠对四氯化碳性和半乳糖胺性肝损伤及能诱导小鼠对醋氨酚性肝损伤产生明显的保护作用。本实验观察了吲哚美辛是否对刀豆蛋白A（ConA）诱导的肝损伤也有保护作用。用Balb／c雄性小白鼠24只，随机分为3组，实验前16h开始禁食，自由饮水。吲哚美辛浓度0．5mg／1ml，在肝损伤模型制备前12h皮下注射一次（10mg／kg），而急性肝损伤动物模型的制备采用ConA尾静脉注射20mg／kg，0．3ml／只；以无菌磷酸盐缓冲液0．3ml／只同法注射为正常对照。在小鼠注射ConA或磷酸盐缓冲液后Zh各组随机抽取2只鼠按常规方法制…     

四氯化碳致小鼠急性肝损伤的性别差异及其与雄激素受体表达的关系

目的比较CCl4对不同性别小鼠急性肝损伤的诱导作用及其对肝脏雄激素受体(AR)表达的影响。方法健康成年昆明小鼠70只,随机分为CCl4雄性组、CCl4雌性组、雄性对照组,雌性对照组。50%CCl4-粟米油溶液皮下注射,0.6ml/100g体重,1周2次,诱导小鼠急性肝损伤。造模第7天处死各组动物取材固定,常规HE染色比较不同组别小鼠肝组织病理变化;免疫组织化学法检测各组小鼠肝脏AR的表达,根据阳性细胞反应强度及百分比设定0级(阴性)及1-3级(阳性)标准,双盲计分法统计各组AR表达分值。结果实验组CCl4造模过程中雄性组小鼠死亡率为60%(15/25),明显高于雌性组(12%,3/25),对照组小鼠无死亡(0/10,0/10)。肝组织HE染色结果可见CCl4诱导的急性肝损伤主要部位为肝小叶周围的门管区及界板区,损伤部位肝细胞出现脂肪变,少数肝组织出现点状坏死。免疫组化显示雄性及雌性对照组小鼠肝细胞AR呈弱阳性表达,不同性别小鼠肝细胞AR表达差别无统计学意义;实验组各组别肝小叶周围受损肝细胞出现较强的AR表达,其中CCl4雄性组AR表达分值明显高于CCl4雌性组小鼠(P<0.01)。结论雄性小鼠对急性肝损伤的耐受性低于雌性小鼠,其中AR的高表达与CCl4诱导的急性肝损伤性别差异密切相关。     

同种MHC基因胸腺转移诱导小鼠心肌移植耐受

目的：通过胸腺内注射表达外源性主要组织相容性抗原复合物（MHC）抗原质粒PXN（N2－B19－H－2Kb），诱导异基因小鼠心肌移植耐受。方法：给BALB／C小鼠胸腺内注射质粒PXN（N2－B19－H－2Kb），将外源性的编码C57BL／6小鼠MHCI类抗原的H－2KbcDNA转移到BALBC／C小鼠胸腺，2周后行C57BL／6小鼠心肌移植。用聚合酶链反应（PCR），反转录聚合酶链反应（RT－PCR），单克隆抗体免疫萤光染色流式细胞仪检测BALB／C小鼠胸腺细胞DNA，mRNA和MHC蛋白质表达。结果：BALB／C小鼠胸腺细胞表面有外源性MHC分子表达，转染效率为5．1％，胸腺内注射质粒PXN（N2－mg－H－2Kb）能明显延长移植小鼠心肌的存活时间，平均17d，对照为8d（P＜0．01）。结论：同种MHC基因转移至受体鼠胸腺可以诱导特异性的免疫耐受。     

枯否细胞在刀豆蛋白A诱导的急性肝损伤中的作用

给小鼠用刀豆蛋白以O，YIAWkg）尾静脉注射，复制实验性急性肝损伤模型，通过检测血浆丙氨酸氨基转移酶（ALT），肿瘤坏死因子．a（’FNF－a）、光镜和电镜观察下肝组织病理学变化评价肝损伤。雄性国出VCjJ’鼠，体重20－3（），6－7周龄，实验前16h禁食，动物由湖北省医科院实验动物中心提供。随机将实验小鼠分为对照组（n＝8）、o）’lrt组（n＝8）和二氧化硅（Stq）＋（ConA组（n＝8）。对照组尾静脉注射无菌磷酸盐缓冲液（PBS）0．3ml/只，ConA组尾静脉注射见onA20mg/kg，SiO2＋ConA组在静脉注射haA20lug／kg前18h分别向尾…     

小鼠骨骼肌电转移hPON1 Q基因可以减轻CCl4诱导的急性肝损伤

目的 研究人Q型对氧磷酶1(human paraoxonase 1 Q,hPON1Q)转基因表达对小鼠四氯化碳(carbon tetrachloride,CCl4)诱导急性肝损伤的缓解效果,为防治肝脏疾病寻找新的途径.方法 小鼠骨骼肌直接注射含hPON1Q的真核表达质粒裸DNA并用电刺激介导表达,测量血清芳香酯酶的活性变化显示hPON1Q转基因表达效果,并使用血清谷丙转氨酶(ALT)、谷草转氨酶(AST)为指标及肝组织病理切片检测肝损伤的程度.结果 hPON1Q转基因表达小鼠血清中芳香酯酶活性提高约50%,并可持续到16 d以后.使用PON1裸DNA电刺激治疗组比对照组小鼠在用CCl4诱导24 h后血清芳香酯酶活性高60%,两种血清转氨酶指标及肝组织切片的病理学分析表明肝脏损伤程度有明显的减轻.结论 电刺激介导的重组人PON1Q基因裸DNA在小鼠体内的表达对CCl4诱导的肝损伤具有显著的防护作用.     

血小板第4因子对急性放射损伤小鼠骨髓细胞凋亡的影响

目的：研究血小板第4因子（platekt factor 4．PF4）对用5．0 Gy ^60COγ 照射损伤小鼠骨髓细胞凋亡的影响及其作用机制。方法：30只雄性BALB／c小鼠随机分为3组：正常对照组（6只）、PF4处理组（12只）和照射组（12只）。在照射前26、20h分别给PF4处理组小鼠腹腔注射40μg／kg的PF4，再用5．0Gy的^60COγ射线全身均匀照射。照射后4、20h应用流式细胞术（FCM）测定小鼠骨髓细胞的凋亡率；并用Western blot检测凋亡相关蛋白Bax的表达。结果：照射后4、20hPF4处理组的小鼠骨髓细胞的凋亡率低于照射组，两组比较差异有统计学意义（P〈0．01）。Western blot检测显示照射后4、20h照射组小鼠骨髓细胞Bax的表达要比正常对照组和PF4处理组的表达要高。结论：PF4可以抑制辐射所致小鼠骨髓细胞的凋亡。此保护机制可能与促凋亡蛋白Bax表达的下调有关。     

球孢菌素对超抗原SEB致小鼠肝损伤的保护作用

用超抗原葡萄球菌肠毒素Ｂ（ＳＥＢ）、Ｄ－氨基半乳糖（Ｄ－ＧａｌＮ）混合腹腔注射Ｂａｌｂ／ｃ小鼠及预先注射环孢菌素（ＣＳＡ）的小鼠，动态观察小鼠肝细胞变化和血清ＴＮＦ，ＩＦＮ－γ水平及及小鼠死亡率。结果发现ＳＥＢ＋Ｄ－ＧａｌＮ注射后２ｈ、６ｈ时出现肝细胞凋亡，１２ｈ后出现肝坏死，小鼠２４小时死亡率达５０％。小鼠血清ＴＮＦ２ｈ升到最高，ＩＦＮ－γ在６－１２ｈ较高。而预注ＣＳＡ的小鼠上述指标正常。推测Ｓ     

CD自杀基因联合GM-CSF基因治疗的抗肿瘤作用及免疫机理

目的研究自杀基因与粒细胞－巨噬细胞集落刺激因子（ＧＭ－ＣＳＦ）基因联合治疗抗肿瘤作用及免疫机理。方法小鼠皮下接种黑色素瘤Ｂ１６Ｆ１０细胞３天后,分别在肿瘤局部直接注射表达小鼠ＧＭ－ＣＳＦ的重组腺病毒ＡｄＧＭ－ＣＳＦ和表达大肠杆菌胞嘧啶脱氨酶（ＣＤ）基因的腺病毒Ａｄ－ＣＤ,然后连续１０天腹腔注射５氟胞嘧啶（５ＦＣ）（ＡｄＣＤ／５ＦＣ／ＡｄＧＭＣＳＦ组）、单用ＡｄＣＤ／５ＦＣ组、单用ＡｄＧＭ－ＣＳＦ组、注射对照病毒ＡｄｌａｃＺ／５ＦＣ组或ＰＢＳ组。结果与接受ＡｄＣＤ／５ＦＣ、ＡｄＧＭ－ＣＳＦ、ＡｄｌａｃＺ／５ＦＣ或ＰＢＳ治疗的荷瘤小鼠比较,经联合治疗后荷瘤小鼠皮下肿瘤结节的生长明显受到抑制,荷瘤小鼠的存活期明显延长（Ｐ＜０．０１）。经ＡｄＣＤ／５ＦＣ／ＡｄＧＭＣＳＦ联合基因治疗后,肿瘤瘤体内或瘤周有大量树突状细胞、ＣＤ８＋Ｔ细胞浸润,黑色素瘤细胞表达ＭＨＣ－Ⅰ和Ｂ７－１分子明显增加,荷瘤小鼠脾细胞对Ｂ１６Ｆ１０黑色素瘤细胞特异性杀伤功能增强。结论联合应用自杀基因和ＧＭ－ＣＳＦ基因转移可以直接杀伤肿瘤细胞,又可提高机体对肿瘤的免疫应答,两者可协同发挥抗肿瘤作用     

转录因子Hand2在妊娠期糖尿病胎鼠心脏发育过程中的表达

目的：了解妊娠糖尿病（ gestational diabetes mellitus,GDM）母鼠胎鼠心脏发育过程中碱性螺旋-环-螺旋蛋白（ basic helix-loop-helix,bHLH）转录因子Hand2表达的变化规律,探讨其在GDM胎鼠心脏发育异常中的作用机制。方法：114只成年雌性SD大鼠,空白对照组（ n＝24）、GDM组（ n＝30）、阴性对照组（ n＝30）及GDM＋胰岛素干预组（ n＝30）;空白对照组不予任何处理;GDM组腹腔注射2％链脲佐菌素（ streptozotocin,STZ;每只40 mg /kg）;阴性对照组腹腔注射等量的柠檬酸－柠檬酸钠缓冲液（ STZ溶剂）;GDM＋胰岛素干预组在GDM建模成功后皮下注射中效胰岛素控制空腹血糖在正常范围。给药72 h后每天测血糖及体质量,各组分别于孕12 d （ embryotic day 12, E12）、E15和E19剖取胎鼠心脏组织HE染色观察心脏组织病理变化,免疫组化检测Hand2蛋白的表达,实时荧光定量PCR检测Hand2 mRNA的表达,Western blotting检测Hand2蛋白表达的变化。结果：各组Hand2蛋白的表达呈动态变化：E12可见表达,E15时表达增加,E19时Hand2蛋白表达最高,E12和E15 GDM组Hand2 mRNA及蛋白在胎鼠心肌细胞中的表达呈现下降趋势,差异有统计学意义（ P＜0．05）。结论：妊娠糖尿病母鼠其胎鼠心脏发育异常的发生率明显升高;Hand2 mRNA及蛋白在妊娠糖尿病胎鼠E12和E15心脏表达水平明显下降,提示与GDM胎鼠心脏发育异常相关。     

CD自杀基因联合GM—CSF基因治疗的抗肿瘤作用及免 …

目的 研究自杀基因与粒细胞－巨噬细胞集落刺激因子（ＧＭ－ＣＳＦ）基因联合治疗抗肿瘤作用及免疫机理。方法 小鼠皮下接种黑色素瘤Ｂ１６Ｆ１０细胞３天后,分别在肿瘤局部直接注射表达小鼠ＧＭ－ＣＳＦ的重组腺病毒ＡｄＧＭ－ＣＳＦ和表达大肠杆菌胞嘧啶脱氨酶（ＣＤ）基因的腺病毒Ａｄ－ＣＤ,然后连续１０天腹腔注射５氟胞嘧啶（５ＦＣ）Ａ（ＡｄＣＤ／５ＦＣ／ＡｄＧＭＣＳＦ组）,单用ＡｄＣＤ／５ＦＣ组,单用ＡｄＧＭ－Ｃ     

Liver cell necrosis and regeneration following injections of carbon tetrachloride. Effects of the thyrotropin-releasing hormone and somatostatin

Mice were given 10 micrograms somatostatin or 25 micrograms TRH intraperitoneally 10 min before s.c. injection of 2 or 20 mg CCl4. The extent of liver cell necrosis and nuclear size were measured by the electronic Mini Mop method and the extent of necrosis and nuclear pleomorphism were estimated by a visual linear analogue scale of 100 mm, and compared to plasma concentrations of ASAT and ALAT. Pre-treatment with TRH or somatostatin resulted in significant reduction in the extent of necrosis 24 h after CCl4-injections (25%), with a lowering of ASAT from 13209 +/- 2955 U/l to 5144 +/- 924 after TRH and to 6186 +/- 966 after somatostatin, and of ALAT from 14343 +/- 3209 to 7718 +/- 1727 and 6494 +/- 1253 U/l, respectively. After 3 days the necroses were reduced from 16.5 +/- 1.7% by the Minimop method to 1.4 +/- 0.5% (90%) in mice given CCl4 alone, and from 12.3 +/- 1.7% to 3.8 +/- 1.2% in mice pretreated with TRH, and from 12.3 +/- 1.8% to 3.8 +/- 1.7% (70%) in mice pretreated with somatostatin. The plasma concentrations of ASAT and ALAT were reduced correspondingly. After 5 days no necroses were seen, and the plasma ASAT and ALAT were normal. After 6 months of weekly injections of TRH or somatostatin before 20 mg CCl4 the liver cell nuclear size (10.5 and 9.7 0.3 mu 2) was similar to that after CCl4 alone (9.7 0.3 mu 2), and twice that of controls (4.6-5.4 0.1 mu 2). Liver cell necrosis was not seen. The plasma concentrations of ASAT (131 8.6-162 11.3) and ALAT (98 8-104 9 Iu/l) were similarly 2-3 times those in controls. TRH and somatostatin thus reduced liver cell injury and delayed regeneration after single injections of CCl4. After 6 months of weekly injections no effects were observed.     

Tolerance of aged Fischer 344 rats against chlordecone-amplified carbon tetrachloride toxicity

We have investigated the effects of chlordecone 1(CD)+CCl4 combination in adult (3 months), middle aged (14 months), and old aged (24 months) male Fischer 344 (F344) rats. After a non-toxic dietary regimen of CD (10 ppm) or normal powdered diet for 15 days, rats received a single non-toxic dose of CCl4 (100 microl/kg, i.p., 1:4 in corn oil) or corn oil (500 microl/kg, i.p.) alone on day 16. Liver injury was assessed by plasma ALT, AST, and histopathology during a time course of 0-96 h. Liver tissue repair was measured by [3H-CH3]-thymidine (3H-T) incorporation into hepatic nuclear DNA and proliferating cell nuclear antigen (PCNA) immunohistochemistry. Hepatomicrosomal CYP2E1 protein, enzyme activity, and covalent binding of 14CCl4-derived radiolabel were measured in normal and CD fed rats. Exposure to CCl4 alone caused modest liver injury only in 14- and 24-month-old rats but neither progression of injury nor mortality. The CD+CCl4 combination led to 100% mortality in 3-month-old rats by 72 h, whereas none of the 14- and 24-month-old rats died. Both 3- and 14-month-old rats exposed to CD+Cl4 had identical liver injury up to 36 h indicating that bioactivation-mediated CCl4 injury was the same in the two age groups. Thereafter, liver injury escalated only in 3-month-old while it declined in 14-month-old rats. In 24-month-old rats initial liver injury at 6 h was similar to the 3- and 14-month-old rats and thereafter did not develop to the level of the other two age groups, recovering from injury by 96 h as in the 14-month-old rats. Neither hepatomicrosomal CYP2E1 protein nor the associated p-nitrophenol hydroxylase activity or covalent binding of 14CCl4-derived radiolabel to liver tissue differed between the age groups or diet regimens 2 h after the administration of 14CCl4. Compensatory liver tissue repair (3H-T, PCNA) was prompt and robust soon after CCl4 liver injury in the 14- and 24-month-old rats. In stark contrast, in the 3-month-old rats it failed allowing unabated progression of liver injury. These findings suggest that stimulation of early onset and robust liver tissue repair rescue the 14- and 24-month-old F344 rats from the lethal effect of the CD+CCl4 combination.     

丹参酮IIA对CCl4诱导小鼠急性肝损伤的保护作用

目的 研究丹参酮IIA(tanshinone ⅡA, Tan ⅡA)对CCl4诱导小鼠急性肝损伤的抗氧化、保护作用及其可能的作用机制。 方法 将C57BL/6J小鼠随机分成正常组、CCl4组以及Tan ⅡA保护组(Tan ⅡA 20 mg/kg+CCl4),每组10只。腹腔注射CCl4构建小鼠急性肝损伤模型。计算各组小鼠的肝脏指数,检测血清AST和ALT活性,测定肝组织SOD活性及GSH、MDA含量,HE染色观察肝组织病理变化,免疫组织化学法和Western blot检测肝组织PI3K、p-PI3K、Akt、p-Akt、Nrf2和HO-1蛋白表达水平。 结果 与CCl4组相比,Tan ⅡA保护组肝脏指数显著下降(P<0.01),血清AST(P<0.01)和ALT活性降低(P<0.05),肝组织SOD活性(P<0.01)及GSH含量升高(P<0.05),MDA含量降低(P<0.05),肝组织病理变化得到显著改善。同时,Tan ⅡA使肝组织p-PI3K和p-Akt表达水平明显升高(P<0.01),显著诱导Nrf2转位入核(P<0.01),促使其下游靶蛋白HO-1表达水平明显升高(P<0.01)。 结论 Tan ⅡA能够显著改善CCl4诱导的急性肝损伤,其机制可能与PI3K/Akt/Nrf2/HO-1信号通路有关。     

Effects of the prostaglandin E2 analogue enprostil on the carbon tetrachloride-induced necrosis of liver cells in mice.

Female mice, eight weeks old, were injected with carbon tetrachloride (CCl4) (10 mg subcutaneously). Groups of mice (n = 10-30) were then injected with enprostil (E) 2, 20 or 50 micrograms/kg body weight (bw) intraperitoneally 15 min and two h after, or E 100 micrograms/kg bw two h after the CCl4 injection. The mice were killed after 24, 48 or 72 h. Plasma activity concentrations of alanine aminotransferase (ALAT) were determined in blood specimens from the iliac veins. The extent of liver cell necrosis in histological sections was recorded on a 100 mm Visual Analogue Scale (VAS) and measured using the electronic Mini Mop method. In the group given the highest single dose of E (100 micrograms/kg) a significant lowering of the CCl4-induced liver cell necrosis was found after 24 h. No significant differences were found after 48 and 72 h. In the other groups injected with lower doses of E after CCl4, no significant differences were found compared to groups injected with CCl4 alone.     

Annexin V assay-proven anti-apoptotic effect of ascorbic acid 2-glucoside after cold ischemia/reperfusion injury in rat liver transplantation

Controversy exists over whether the predominant cell death of hepatocytes is due to apoptosis or necrosis after ischemia/reperfusion injury. In this study we investigated the predominant cell death of hepatocytes after cold ischemia/reperfusion injury using the Annexin V-based assay, and evaluated the anti-apoptotic effect of ascorbic acid 2-glucoside (AA-2G) added to the University of Wisconsin solution (UW solution) in rat liver transplantation. The retrieved liver was preserved in 4 UW solution for 24 h, and then transplanted orthotopically to the syngeneic Wistar recipient. The animals were divided into 2 groups, a control group (n=10), in which liver grafts were preserved in UW solution (4), and an AA-2G group (n=10), in which liver grafts were preserved in UW solution (4) with AA-2G (100 ug/ml). The serum AST level 4 h after reperfusion in the control group was significantly suppressed in the AA-2G group, and the bile production of the liver graft in the AA-2G group was well recovered. The mean survival time in the AA-2G group was significantly improved compared with that in the control group. Annexin-V and Propidium iodide staining 4 h after reperfusion showed a significantly higher percentage of viable hepatocytes in the AA-2G group compared with the control group (93.4 +/- 2.0 vs. 80.3 +- 2.1%, P<0.05). In the control group, the main cell death of hepatocytes was apoptosis (early apoptosis: 10.0 +- 4.7%, late apoptosis: 6.4 +/- 1.7%). The addition of AA-2G to the UW solution significantly inhibited both early and late apoptotic cell death 4 h after reperfusion (early apoptosis: 0.98 +/- 0.88%, late apoptosis: 2.2 +/- 1.1%). The expression of caspase 9 in the immunostaining of the liver graft was suppressed in the AA-2G group compared with in the control group. Our study using the Annexin V-based assay provided evidence that the predominant cell death of hepatocytes was apoptosis after 24 h cold ischemia/reperfusion injury in rat liver transplantation. The addition of AA-2G to the UW solution attenuated 24 h cold ischemia/reperfusion injury by inhibiting the apoptosis of hepatocytes.     

BMP-7 attenuates liver fibrosis via regulation of epidermal growth factor receptor

The aim of this study was to elucidate the effect of bone morphogenetic protein-7 (BMP-7) on liver fibrosis induced by carbon tetrachloride (CCl4) in vivo and on the hepatic stellate cells (HSC) activation in vitro. In vivo, thirty male ICR mice were randomly allocated to three groups, the control group (n = 6), the CCl4 group (n = 18) and the BMP-7+CCl4 group (n = 6). The model of liver fibrosis was induced by intraperitoneal injection with CCl4 three times per week lasting for 12 weeks in CCl4 group and the BMP-7+CCl4 group. After 8 weeks injection with CCl4, mice were intraperitoneal injected with human recombinant BMP-7 in BMP-7+CCl4 group. Meanwhile, mice in the CCl4 group were only intraperitoneal injection with equal amount of saline. The degree of liver fibrosis was assessed by HE and Masson’s staining. PCR and western blot were used to detect mRNA and protein levels. In BMP-7+CCl4 group, serum levels of alanine aminotransferase (ALT) and aminotransferase (AST) were decreased and serum albumin (Alb) was increased. Meanwhile, the expressions of transforming growth factor-β1 (TGF-β1) and α-smooth muscle actin (α-SMA) were down-regulated by BMP-7 intervention as compared to the CCl4 group (P < 0.05). Furthermore, BMP-7 also suppressed the expression of epidermal growth factor receptor (EGFR) and phosphorylated-epidermal growth factor receptor (pEGFR). HE and Masson stain showed that liver damage was alleviated in BMP-7+CCl4 group. In vitro study, expression of EGFR, TGF-β1 and α-SMA were down regulated by BMP-7 dose-dependently, indicating it might effect on suppression of HSC activation. Therefore, our data indicate BMP-7 was capable of inhibiting liver fibrosis and suppressing HSCs activation, and these effects might rely on its crosstalk with EGFR and TGF-β1. We suggest that BMP-7 may be a potential reagentfor the prevention and treatment of liver fibrosis.     

Carbon tetrachloride-mediated lipid peroxidation induces early mitochondrial alterations in mouse liver

Although carbon tetrachloride (CCl(4))-induced acute and chronic hepatotoxicity have been extensively studied, little is known about the very early in vivo effects of this organic solvent on oxidative stress and mitochondrial function. In this study, mice were treated with CCl(4) (1.5?ml/kg ie 2.38?g/kg) and parameters related to liver damage, lipid peroxidation, stress/defense and mitochondria were studied 3?h later. Some CCl(4)-intoxicated mice were also pretreated with the cytochrome P450 2E1 inhibitor diethyldithiocarbamate or the antioxidants Trolox C and dehydroepiandrosterone. CCl(4) induced a moderate elevation of aminotransferases, swelling of centrilobular hepatocytes, lipid peroxidation, reduction of cytochrome P4502E1 mRNA levels and a massive increase in mRNA expression of heme oxygenase-1 and heat shock protein 70. Moreover, CCl(4) intoxication induced a severe decrease of mitochondrial respiratory chain complex IV activity, mitochondrial DNA depletion and damage as well as ultrastructural alterations. Whereas DDTC totally or partially prevented all these hepatic toxic events, both antioxidants protected only against liver lipid peroxidation and mitochondrial damage. Taken together, our results suggest that lipid peroxidation is primarily implicated in CCl(4)-induced early mitochondrial injury. However, lipid peroxidation-independent mechanisms seem to be involved in CCl(4)-induced early hepatocyte swelling and changes in expression of stress/defense-related genes. Antioxidant therapy may not be an efficient strategy to block early liver damage after CCl(4) intoxication.     

The chemokine receptor CXCR3 limits injury after acute toxic liver damage

Although acute liver failure is a rare disease, its presence is associated with high morbidity and mortality in affected patients. While a contribution of the immune system to the outcome of toxic liver failure is anticipated, functionally relevant immune cell receptors for liver cell damage need to be better defined. We here investigate the relevance of the chemokine receptor CXCR3, which is important for hepatic immune cell infiltration, in a model of experimental acute liver failure. Liver injury was induced by a single intraperitoneal injection of carbon tetrachloride (CCl(4)) in CXCR3(-/-), CCR1(-/-), CCR5(-/-) and wild-type mice. In this model, CXCR3(-/-) mice displayed augmented liver damage compared with all other mouse strains as assessed by liver histology and serum transaminases 24 and 72?h after injury. Phenotypically, CXCR3(-/-) mice had significantly reduced intrahepatic NK and NKT cells after injury at all investigated time points (all P<0.05), but strongly elevated expression levels of IL1-β, TNF-α and IFN-γ. In line with a functional role of innate immune cells, wild-type mice depleted for NK cells with an anti-ASIALO GM1 antibody before liver injury also displayed increased liver injury after CCl(4) challenge. CXCR3(-/-) and NK cell-depleted mice show reduced apoptotic liver cells (TUNEL assay), but more necrotic hepatocytes. Functionally, the augmented liver cell necrosis in CXCR3(-/-) and NK cell-depleted mice was associated with increased expression of high mobility group 1 (HMGB1) protein and a consecutive enhanced infiltration of neutrophils into the liver. In conclusion, the results demonstrate a primarily unexpected beneficial role of CXCR3 in acute toxic liver injury. These findings should be taken into account when planning trials with CXCR3 antagonists.     

Acute liver toxicity by carbon tetrachloride in HSP70 knock out mice

The effects of carbon tetrachloride (CCl(4)) treatment on acute liver damage in knock out (heat shock proteins -- HSP70-/-) mice and wild-type (C57BL/6) mice were examined. Acute liver injury was induced by a single intraperitoneal injection of 0.3 ML/kg CCl(4) in olive oil. Mice were sacrificed at 12, 24, 48 and 72 h after treatment. To assess hepatotoxicity, alanine transaminase, neutrophil infiltration and degree of necrosis were measured. Western blot analysis was employed for heat shock proteins. The result revealed that HSP70-/- mice showed higher alanine transaminase levels and a more severe degree of neutrophilic infiltration and necrosis than those of wild-type mice. Furthermore, HSP70-/- mice recovered more slowly from CCl(4) treatment. In HSP70-/- mice, HSP47 was overexpressed. Therefore, HSP70-/- mice could be an adequate model of acute liver toxicity study.