Immunotherapy for nonalcoholic steatohepatitis using the multiple cytokine production modulator Y-40138

AIM: To investigate the possible use of the multiple cytokine production modulator, Y-40138, as a novel immunotherapy in the rat nonalcoholic steatohepatitis(NASH) model.METHODS: We allocated 6-wk-old male F344 rats to choline-supplemented, L-amino acid-defined (CSAA) diet (control group), CSAA diet + Y-40138 (control +Y-40138 group), choline-deficient, L-amino acid-defined (CDAA) diet (NASH group), or CDAA diet + Y-40138 (NASH + Y-40138 group). In each group, we measured the plasma alanine aminotransferase (ALT) levels, and the plasma and liver levels of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), and interleukin-10 (IL-10). Tissue specimens of phosphate buffered saline-perfused liver were subjected to hematoxylin and eosin staining, Azan staining, Sirius red staining, and immunohistochemical staining (for Kupffer cells and TNF-α). We then extracted Kupffer cells from the collagenase-perfused livers using the Percoll gradient centrifugation method, and measured the TNF-α levels in the supernatant ( in vitro TNF-α production by Kupffer cells) using an enzyme-linked immunosorbent assay kit. RESULTS: In comparison to the NASH group, serum ALT elevation was mild, production of serum and liver TNF-α and IFN-γ was inhibited, and IL-10 production was increased in the NASH + Y-40138 group. Amelioration of liver histology was also noted in the NASH + Y-40138 group. Kupffer cell immunohistochemical staining revealed no differences between groups, whereas TNF-α immunohistochemical staining showed fewer stained cells in the NASH + Y-40138 group than in the NASH group. The TNF-α levels in the in-vitro Kupffer cell culture supernatant were lower in the NASH + Y-40138 group than in the NASH group.CONCLUSION: Administration of Y-40138 to NASH model rats reduced hepatic inflammation and suppressed fibrosis. These results indicate that the multiple cytokine production modulator, Y-40138, is promising as a novel treatment for NASH.     

疏肝祛瘀通络降浊法对大鼠非酒精性脂肪性肝炎的保护作用

目的探讨非酒精性脂肪性肝炎大鼠内毒素性肝损伤机制及中药对其影响。方法用喂饲高脂饮食的方法建立非酒精性脂肪性肝炎大鼠模型。4周后用疏肝祛瘀通络降浊法分小、中、大剂量进行治疗,12周后处死测定血脂、ALT、内毒素(ET)、肿瘤坏死因子(TNF-α)和白细胞介素(IL-1β)的含量;免疫组化法观察肝组织CD14和核转录因子(NF-κB)的表达;RT-PCR检测脂多糖结合蛋白(LBP)和4型Toll样受体(TLR-4)mRNA的表达。同期正常饮食饲养大鼠作对照。结果第12周时,模型组大鼠腹主动脉血清内毒素水平较正常组明显升高,有显著性差异;中剂量治疗组大鼠血清ET、TNF-α、IL-1β水平明显低于模型组,差异有显著意义。模型组大鼠肝组织CD14阳性细胞数量明显增多,主要分布于肝窦内,部分呈灶型聚集;与模型组相比,中剂量治疗组大鼠肝组织CD14阳性细胞数量明显减少。模型组可见少量细胞核染色的NF-κB阳性细胞散在分布于汇管区。模型组肝组织LBPmRNA和TLR-4mRNA表达均明显上调,与正常组比较差异均有显著意义;中剂量治疗组大鼠肝组织LBPmRNA和TLR-4mRNA表达均较模型组明显下调,且有显著性差异。结论疏肝祛瘀通络降浊法对非酒精性脂肪肝有疗效,可能与其降低血清内毒素水平和下调肝组织内毒素相关受体表达继而减轻炎症性肝损害有关。     

Decreased phagocytic activity of Kupffer cells in a rat nonalcoholic steatohepatitis model

AIM： TO investigate Kupffer cell dynamics and phagocytic activity, using a rat nonalcoholic steatohepatitis （NASH） model.
METHODS： Male F344 rats were fed either a control diet or a choline-deficient L-amino aciddefined （CDAA） diet, followed by contrast enhanced ultrasonography （CEUS） using Levovist. The uptake of latex beads by the Kupffer cells was determined by fluorescent microscopy. The status of the Kupffer cells was compared between the two groups, using the immunohistochemical staining technique.
RESULTS： After 4 or more wk of the CDAA diet, CEUS examination revealed a decrease in the signal intensity, 20 min after intravenous Levovist. Fluorescent microscopic examination showed that the uptake of latex beads by the Kupffer cells was reduced at week 1 and 2 in the study group, compared with the controls, with no further reduction after 3 wk. Immunohistochemical staining revealed no significant difference in the Kupffer cell counts between the control group and the CDAA group.
CONCLUSION： CEUS examination using Levovist demonstrated reduced contrast effect and phagocytic activity in the liver parenchymal phase, although the Kupffer cell numbers were unchanged, indicating reduced phagocytic function of the Kupffer cells in the rat NASH model. We believe that CEUS examination using Levovist is a useful screening modality, which can detect NASH in fatty liver patients.     

非酒精性脂肪性肝炎大鼠肝脏内毒素受体表达上调

目的观察大鼠非酒精性脂肪性肝炎(NASH)伴肝纤维化模型形成过程中,肝脏内毒素受体表达的动态变化,以探讨NASH的发病机制。方法 45只雄性SD大鼠以高脂饮食喂养,分批于实验 8,12、16、24周处死。免疫组织化学法观察CD14表达,逆转录聚合酶链反应(RT-PCR)法观察4型toll 样受体(TLR4)mRNA表达,RT-PCR法和酶联免疫吸附法分别测定肝脏和血清肿瘤坏死因子a(TNF a) 表达。同期正常饮食饲养大鼠作对照。结果实验8周大鼠单纯性脂肪肝阶段肝脏CD14和TLR4的表达就较正常对照上调(25．9±11．9对12．4 5．7、1．75±0．81对O．98±0．33,P<0．01和P<0．05),12周随着脂肪性肝炎的出现进行性增高(61．8±21．9和1．88±0．72,P值均<0．05),于16周达高峰(71．5±21．3 对5．64±0．87,P值均<0．01),24周略有回落(67．7±16．6和4．98±0．72,P值均<0.01)。肝脏和血清 TNF a表达也从8周开始上调,此后一直维持高水平表达。结论大鼠NASH形成过程中,肝脏内毒素受体CD14和TLR4表达逐渐上调。这可能是NASH大鼠内毒素肝损伤敏感性增强的原因之一,在NASH的发病中起了重要作用。     

大鼠非酒精性脂肪性肝炎形成过程中血清内毒素含量的变化

目的 探讨内毒素在非酒精性脂肪性肝炎发病中的作用。方法 通过高脂饮食建立大鼠非酒精性脂肪性肝炎(NASH)模型,并在实验第4、8、12、16、24周分批处死,同期设正常饮食组作为对照。腹主动脉采血,测定血清内毒素,肿瘤坏死因子(TNFα)和白细胞介素-1(IL-1)β水平,肝组织切片行溶菌酶、CD14免疫组织化学染色。 结果 成功建立大鼠NASH伴肝纤维化模型,NASH大鼠外周血内毒素水甲仅在24周脂肪性肝炎肝纤维化阶段明显升高为(0.23±O.06)Eu/L,对照组为(0.15±0.03)Eu/L(t>2.179,P<0.05),而4周起肝组织CD14表达就上调,溶菌酶阳性的库普弗细胞被激活,并随着实验的进展更加明显。血清TNFα水平从8周起明显增高为(26.39±24.21)pg/ml,对照组为(9.82±9.29)pg/ml(t>2.145,P<0.05),IL-1β从16周起升高为(23.76±21.81)pg/ml,对照组为(6.25±2.98)pg/ml(t>2.145,P<0.05)。 结论 NASH时存在内毒素性肝损伤。内毒素激活肝脏库普弗细胞以及促使TNFα等细胞因子释放可能是NASH的发病机制之一。     

Decreased accumulation of ultrasound contrast in the liver of nonalcoholic steatohepatitis rat model

AIM:To investigate the diagnosis of nonalcoholic steatohepatitis(NASH) using contrast ultrasonography in the NASH rat model.METHODS:The liver in methionine choline-deficient diet(MCDD) rats,a NASH model constructed by feeding an MCDD,was examined by contrast ultrasonography at weeks 2,4,8,12 and 16,with late phase images of contrast ultrasonography(Kupffer imaging) in which contrast enhancement was achieved by incorporation of a contrast agent by Kupffer cells(KCs),and images were compared to those in rats ...     

枯否氏细胞在大鼠非酒精性脂肪性肝炎发病中的作用

目的：探讨枯否氏细胞大鼠非酒精性脂肪性肝炎（non-alcoholic steatohepatitis,NASH)发病中的作用,方法：19只雄性SD大鼠随机分为模型组（10只）和正常组（9只）,分别预高脂肪饮食和标准饮食饲养12周,HE梁色观察肝细胞切片病理学改变,透射电镜和溶菌酶免疫组织化学染色观察枯否氏细胞的数量和形态。结果：模型组大鼠均出现肥胖,高脂血症伴肝细胞大泡性脂肪变,小叶内炎症细胞浸润和坏死,与正常相比,模型组肝小叶内枯否氏细胞数显著增加,并呈活化状态,模型组枯否氏细胞变化与其肝病理学改变相一致,结论：高脂饮食大鼠肝脏枯否氏细胞增多,并可能与其脂肪性肝炎的发病有关。     

脂多糖预处理对非酒精性脂肪性肝炎的影响

目的 探讨脂多糖(lipopolysaccharide,LPS)预处理对非酒精性脂肪性肝炎(nonalcoholic steatohepatitis,NASH)的影响.方法 选取24只成年雄性Wistar大鼠,分为正常对照组、NASH组和LPS预处理组.NASH组饲以高糖高脂饲料;LPS预处理组饲料同肝损伤组,隔日皮下注射LPS 0.5 mg/kg;正常对照组饲以普通饲料;所有大鼠自由进食与饮水.于实验第9周末处死大鼠.制备肝组织切片,计数浸润肝组织的淋巴细胞;测定血浆内毒素水平和丙氨酸转氨酶(ALT)活性、肿瘤坏死因子-α(TNF-α)、白细胞介素-10(IL-10)含量.结果 NASH组血浆内毒素水平比正常对照组高;LPS预处理组血浆ALT水平、肝组织淋巴细胞计数与NASH组比较均显著降低;血浆TNF-α水平LPS预处理组与NASH组比较明显降低,而血浆IL-10则相反,差异有统计学意义(P＜0.05).肝组织切片HE染色结果显示,LPS预处理组与NASH组比较,肝细胞内脂肪空泡小、数量少,脂肪变性明显减轻.结论 小剂量LPS预处理与减轻NASH密切相关.其机制可能是LPS预处理影响了细胞因子的释放,导致Th1/Th2细胞因子失衡,Th1向Th2偏离,可能诱导了宿主的免疫耐受,表现为肝组织损伤减轻.

Abstract：

Objective To investigate the changes of Th1/Th2 cytokines and its relationship with lipopolysaccharide (LPS) in pretreatment of relieving nonalcoholic steatohepatitis (NASH).Methods The 24 male Wistar rats were randomly divided into 3 groups: normal control group, liver injury group and LPS pretreatment group. The rats were given normal diet in normal control group,high-sucrose and high-fat diet both in liver injury group and in LPS pretreatment group, and the rats in LPS pretreatment group were given hypodermic injection of LPS 0. 5 mg/kg every other day. The level of plasma endotoxin (ET), activity of alanine aminotransferase (ALT), content of tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) were determined. At the end of week 9, the rats were executed, and the liver tissue slices were prepared to investigate hepatic pathologic change by hematoxylin and eosin (HE) staining.Results The level of plasma ET was significantly higher in liver injury group than in normal control group. The level of plasma ALT and infiltrating lymphocytes in liver tissue were significantly lower in LPS pretreatment group than in liver injury group. The level of plasma TNF-α was significantly lower in LPS pretreatment group compared with liver injury group.In contrast, the level of plasma IL-10 was higher (P＜0. 05). Histology with HE staining showed that hepatocyte steatosis was obviously relieved with smaller lipid droplet in LPS pretreatment group than in liver injury group. Conclusions LPS pretreatment can alleviate high-sucrose and high-fat induced NASH. The disequilibrium of Th1/Th2 cytokines may be an important part of mechanism.     

Lack of interleukin-1α in Kupffer cells attenuates liver inflammation and expression of inflammatory cytokines in hypercholesterolaemic mice

BackgroundThe role of Kupffer cell interleukin (IL)-1 in non-alcoholic steatohepatitis development remains unclear.AimsTo evaluate the role of Kupffer cell IL-1α, IL-1β or IL-1 receptor type-1 (IL-1R1) in steatohepatitis.MethodsC57BL/6 mice were irradiated and transplanted with bone marrow-derived cells from WT, IL-1α−/−, IL-1β−/− or IL-1R1−/− mice combined with Kupffer cell ablation with Gadolinium Chloride, and fed atherogenic diet. Plasma and liver triglycerides and cholesterol, serum alanine aminotransferase (ALT), liver histology and expression levels of inflammatory genes were assessed.ResultsThe ablation and replacement of Kupffer cells with bone marrow-derived cells was confirmed. The atherogenic diet elevated plasma and liver cholesterol, reduced plasma and liver triglycerides and increased serum ALT levels in all groups. Steatosis and steatohepatitis were induced, but without liver fibrosis. A reduction in the severity of portal inflammation was observed only in mice with Kupffer cell deficiency of IL-1α. Accordingly, liver mRNA levels of inflammatory genes encoding for IL-1α, IL-1β, TNFα, SAA1 and IL-6 were significantly lower in mice with Kupffer cell deficiency of IL-1α compared to WT mice.ConclusionSelective deficiency of IL-1α in Kupffer cells reduces liver inflammation and expression of inflammatory cytokines, which may implicate Kupffer cell-derived IL-1α in steatohepatitis development.     

模拟失重对大鼠实验性胃溃疡氧化应激状态的影响

目的探讨模拟失重对乙酸诱导的大鼠实验性胃溃疡氧化应激状态的影响及可能机制。方法 32只SD大鼠随机分为4组,即尾部悬吊7 d组、尾部悬吊14 d组和相应的同步对照组。采用乙酸烧灼法制备大鼠慢性胃溃疡模型,造模后第3天悬吊组大鼠采用尾悬吊法建立模拟失重动物模型。游标卡尺检测胃溃疡面积,生化比色法测定大鼠血清中丙二醛(MDA)含量,超氧化物岐化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)活性。结果与对照7 d组相比,悬吊7 d组大鼠溃疡面积显著增大(t=5.661,P<0.01);与对照14 d组比较,悬吊14 d组溃疡面积显著增大(t=4.233,P<0.01),血清MDA含量及SOD活性显著增高(t=2.641,P<0.05,t=5.758,P<0.01);与悬吊7 d组比较,悬吊14 d组溃疡面积显著减小(t=3.805,P<0.01),血清MDA含量及SOD活性显著增高。血清GSH-PX活性差异无统计学意义(P<0.05)。结论模拟失重可加重溃疡氧化应激反应,延迟溃疡愈合。     

口服抗生素对NASH大鼠肝组织TLR4信号通路的影响

目的观察口服抗生素对非酒精性脂肪性肝炎大鼠代谢性内毒素血症激活肝脏4型Toll样受体(TLR4)信号通路的影响。方法将30只SD大鼠随机分为正常对照组、模型组和干预组,后者给予高脂饮食喂养,正常组予普通饲料喂养。干预组大鼠自第9周起给予环丙沙星灌胃。造模12周末,比较各组门静脉血内毒素、谷丙转氨酶、谷草转氨酶、甘油三酯和空腹血糖水平;计算非酒精性脂肪性肝病评分;采用Real time PCR及Westernblot法检测大鼠肝脏TLR4、胰岛素受体底物-1(IRS-1)mRNA及蛋白表达水平;采用ELISA法检测血清和肝匀浆肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平。结果模型组动物门静脉内毒素为0.361±0.018EU/ml,而正常组为0.324±0.013EU/m(l P<0.05);肝脏TLR4 mRNA水平为正常组的7.7倍,IRS-1 mRNA水平下降69%,血清及肝脏TNF-α分别为105.7±30.1pg/ml和608.7±78.8pg/ml,IL-6分别为60.9±12.5pg/ml和756.4±90.8pg/ml,均显著高于正常组(P<0.05);与模型组比,干预组门静脉血内毒素为0.341±0.016EU/m(lP<0.05),NAS积分为4.40±0.26(P<0.05),肝脏TLR4 mRNA和蛋白表达水平分别下降44%和14%,肝脏IRS1 mRNA和蛋白表达水平分别增加2.3倍和1.6倍,TNF-α和IL-6水平分别为531.1±64.6pg/ml和575.1±84.5pg/m(lP<0.05)。结论 NASH大鼠肝脏TLR4信号通路被激活,口服抗生素可减少肠源性内毒素血症,减轻肝脏炎症。     

枯否细胞在大鼠非酒精性脂肪性肝炎发病中的作用

目的　探讨枯否细胞在大鼠非酒精性脂肪性肝炎（non-alcoholic steatohepatitis,NASH）发病中的作用。方法　19只雄性SD大鼠随机分为模型组（10只）和正常组（9只）,分别予高脂肪饮食和标准饮食饲养12周。HE染色观察肝组织切片病理学改变,透射电镜和溶菌酶免疫组织化学染色观察枯否细胞的数量和形态。结果　模型组大鼠均出现肥胖、高脂血症伴肝细胞大泡性脂肪变、小叶内炎症细胞浸润和坏死。与正常组相比,模型组肝小叶内枯否细胞数显著增加,并呈活化状态;模型组枯否细胞变化与其肝病理学改变相一致。结论　高脂饮食大鼠肝脏枯否细胞增多,并可能与其脂肪性肝炎的发病有关。     

Hepatic vagus nerve regulates Kupffer cell activation via α7 nicotinic acetylcholine receptor in nonalcoholic steatohepatitis

Background

Nonalcoholic fatty liver disease ranges from simple steatosis to nonalcoholic steatohepatitis (NASH). Kupffer cells play a central role in promoting hepatic inflammation, which leads to the development of NASH. We investigated the anti-inflammatory effect of hepatic vagus-mediated stimulation of the α7 nicotinic acetylcholine receptor (α7nAChR) on Kupffer cells in NASH pathogenesis.

Methods

Wild-type (WT) mice undergoing hepatic vagotomy (HV) were fed a methionine- and choline-deficient (MCD) diet for 1 week. α7nAChR knockout (α7KO) chimeric mice were generated by transplanting α7KO bone marrow cells into irradiated and Kupffer cell-deleted WT recipients. Kupffer cells were isolated from WT mice and treated with α7nAChR agonist under stimulation by lipopolysaccharide and/or palmitic acid.

Results

HV aggravated MCD diet-induced NASH in both steatosis and inflammation. The hepatic inflammatory response, including the upregulation of tumor necrosis factor alpha (TNFα), interleukin (IL)-12, and monocyte chemoattractant protein 1 (MCP-1), was accelerated in HV mice, accompanied by the downregulation of PPARα pathway genes. Kupffer cells were highly activated via the phosphorylation and nuclear translocation of nuclear factor-kappa B (NF-κB) in MCD diet-fed HV mice. The α7nAchR agonist suppressed the inflammatory response of primary Kupffer cells induced by lipopolysaccharide and palmitic acid by attenuating the NF-κB cascade. α7KO chimeric mice fed an MCD diet for 1 week developed advanced NASH with highly activated Kupffer cells. The hepatic expression of TNFα, IL-12, and MCP-1 was upregulated in α7KO chimeric mice, accompanied by abnormal lipid metabolism.

Conclusions

Hepatic vagus activity regulates the inflammatory response of Kupffer cells via α7nAChR in NASH development.

     

非酒精性脂肪性肝炎患者肝组织NF-кβ的表达及其意义

目的探讨核因子κβ（NF-κβ）在非酒精性脂肪性肝炎（NASH）患者肝组织中的表达状况及在发病机制中的意义。方法应用免疫组化方法检测41例不同病变程度NASH患者肝组织NF-κβ表达，分析其与NASH患者肝组织病理改变以及血清TNF-α、胰岛素抵抗（IR）之间的关系，并与39例酒精性脂肪肝、50例NASH合并慢性乙型肝炎（CHB）患者进行比较。结果与正常人肝组织中NF-κβ（1．13±0．05）表达比较，NASH（5．09±1．30）、酒精性脂肪肝（4．07±1．54）和NASH合并CHB（6．40±1．41）患者表达均明显增强（P〈0．05）；在NASH肝组织中，NF-κβ表达于肝脂肪变区及炎症活动区的肝窦壁细胞及炎细胞中，其阳性表达随肝脏炎症损伤程度和纤维化程度的加重而增加（P〈0．05），与血清TNF-α水平和IR成正相关（P〈0．05），而与脂肪变程度无明显相关性（P〉0．05）。结论不同类型的脂肪性肝病均存在胰岛素抵抗和肝组织NF-κβ的活化，NF-κβ的活化是非酒精性脂肪肝胰岛素抵抗持续进展的一个重要机制。     

CD14 upregulation as a distinct feature of non-alcoholic fatty liver disease after pancreatoduodenectomy

AIM: To investigate the pathogenesis of non-alcoholic fatty liver disease (NAFLD) after pancreatoduodenectomy (PD). METHODS: A cohort of 82 patients who underwent PD at Okayama University Hospital between 2003 and 2009 was enrolled and the clinicopathological features were compared between patients with and without NAFLD after PD. Computed tomography (CT) images were evaluated every 6 mo after PD for follow-up. Hepatic steatosis was diagnosed on CT when hepatic attenuation values were 40 Hounsfield units. Liver biopsy was performed for 4 of 30 patients with NAFLD after PD who consented to undergo biopsies. To compare NAFLD after PD with NAFLD associated with metabolic syndrome, liver samples were obtained from 10 patients with NAFLD associated with metabolic syndrome [fatty liver, n = 5; non-alcoholic steatohepatitis (NASH), n = 5] by percutaneous ultrasonography-guided liver biopsy. Double-fluorescence immunohistochemistry was applied to examine CD14 expression as a marker of lipopolysaccharide (LPS)-sensitized macrophage cells (Kupffer cells) in liver biopsy specimens. RESULTS: The incidence of postoperative NAFLD was 36.6% (30/82). Univariate analysis identified cancer of the pancreatic head, sex, diameter of the main pancreatic duct, and dissection of the nerve plexus as factors associated with the development of NAFLD after PD. Those patients who developed NAFLD after PD demonstrated significantly decreased levels of serum albumin, total protein, cholesterol and triglycerides compared to patients without NAFLD after PD, but no glucose intolerance or insulin resistance. Liver biopsy was performed in four patients with NAFLD after PD. All four patients showed moderate-to-severe steatosis and NASH was diagnosed in two. Numbers of cells positive for CD68 (a marker of Kupffer cells) and CD14 (a marker of LPS-sensitized Kupffer cells) were counted in all biopsy specimens. The number of CD68+ cells in specimens of NAFLD after PD was significantly increased from that in specimens of NAFLD associated with metabolic syndrome specimens, which indicated the presence of significantly more Kupffer cells in NAFLD after PD than in NAFLD associated with metabolic syndrome. Similarly, more CD14+ cells, namely, LPS-sensitized Kupffer cells, were observed in NAFLD after PD than in NAFLD associated with metabolic syndrome. Regarding NASH, more CD68+ cells and CD14+ cells were observed in NASH after PD specimens than in NASH associated with metabolic syndrome. This showed that more Kupffer cells and more LPS-sensitized Kupffer cells were present in NASH after PD than in NASH associated with metabolic syndrome. These observations suggest that after PD, Kupffer cells and LPS-sensitized Kupffer cells were significantly upregulated, not only in NASH, but also in simple fatty liver. CONCLUSION: NAFLD after PD is characterized by both malnutrition and the up-regulation of CD14 on Kupffer cells. Gut-derived endotoxin appears central to the development of NAFLD after PD.     

理气化痰祛瘀法对非酒精性脂肪性肝炎大鼠脂肪细胞因子表达的影响

[目的]观察理气化痰祛瘀中药对高脂饮食诱导的非酒精性脂肪性肝炎（NASH）大鼠肿瘤坏死因子α（TNF-α）、白细胞介素6（IL-6）、瘦素（1eptin）及其肝组织mRNA水平的影响，探讨其防治NASH的作用机制。[方法]以高脂饮食喂养Wistar大鼠12周，建立大鼠NASH模型，同时以不同剂量的理气化痰祛瘀法中药干预12周，测定大鼠血清丙氨酸氨基转移酶（ALT）、天冬氨酸转氨酶（AST）及游离脂肪酸（FFA）水平，观察肝组织的病理改变，原位杂交技术检测肝组织TNF-α、IL-6、leptinmRNA表达，放免法测定血清TNF-α、IL-6、leptin水平。[结果]NASH大鼠血清ALT、AST、FFA、TNF-α、IL-6、leptin水平较正常大鼠显著升高，肝组织TNF-α、IL-6和leptinmRNA表达显著增强，理气化痰祛瘀法中药能显著改善NASH大鼠肝组织炎症活动程度，显著降低ALT、AST、FFA、TNF-a、IL-6、leptin水平和肝组织TNF-α、IL-6、leptinmRNA表达。[结论]TNF-α、IL-6、leptin参与高脂饮食诱导的大鼠NASH的发生，理气化痰祛瘀中药能调节TNF-α、IL-6、leptin的分泌，防止NASH的进一步发展。     

HIF-1α对非酒精性脂肪性肝病小鼠肝组织的影响*

目的 探讨缺氧诱导因子1α(HIF-1α)在非酒精性脂肪性肝病(NAFLD)进展中的作用。方法 将30只雄性C57BL/6J小鼠随机分为对照组、高脂饮食模型组和蛋氨酸-胆碱缺乏饮食(MCD)模型组,每组10只,建立非酒精性脂肪性肝炎(NASH)模型,分别取肝组织行组织病理学检查,采用缺氧探针检测肝组织缺氧程度,采用Real-time PCR法检测肝组织HIF-1α mRNA水平,采用Western blot法检测肝组织HIF-1α蛋白表达。另取小鼠肝星状细胞JS-1细胞,分为对照组、腺病毒载体组和HIF-1α ShRNA腺病毒载体感染组,采用MTT法检测细胞活性,采用Real-time PCR法检测细胞1型胶原(COL1)和3型胶原(COL3)、TNF-α、IL-1β和TGF-β1 mRNA水平。结果 缺氧探针染色显示高脂饮食模型组和MCD模型组小鼠肝组织染色阳性率分别为85%和78%,显著高于对照组的7%(P<0.05);高脂饮食模型组和MCD模型组小鼠肝组织HIF-1α mRNA水平分别为对照组小鼠的2.1倍和1.6倍(P<0.05),HIF-1α蛋白表达水平也相应地增强;HIF-1α ShRNA腺病毒载体感染细胞活力仅为对照组的37%(P<0.05),细胞COL1、COL3、TNF-α、IL-1β、TGF-β1 mRNA水平也显著降低(P<0.05)。结论 HIF-1α能够促进小鼠NAFLD进展,抑制HIF-1α表达可能能延缓NAFLD进展,值得进一步研究。     

内毒素受体在肝星状细胞的表达及其作用

目的了解内毒素受体在肝星状细胞活化中的变化和作用。方法分离正常大鼠的肝星状细胞，以逆转录聚合酶链反应法检测其在体外培养过程中内毒素受体（CD14和TLR4）mRNA的表达变化。以细胞免疫染色法检测肝星状细胞内毒素受体CD14的表达。制作肝纤维化和肝硬化的大鼠模型，免疫组织化学法动态检测肝组织内CD14和α平滑肌肌动蛋白的表达变化和定位。结果初分离的肝星状细胞表达低水平的CD14 mRNA，不表达TLR4 mRNA，培养活化的肝星状细胞内毒素受体的表达增强，内毒素可上调这种表达。体外培养10d的肝星状细胞表达CD14蛋白，内毒素作用后CD14表达更明显。在肝纤维化的发展过程中，肝组织内CD14阳性细胞增多，阳性细胞多分布于肝窦周围，晚期CD14阳性细胞聚集在纤维隔内，与α平滑肌肌动蛋白阳性细胞的分布一致。结论肝星状细胞在体内外的活化过程中内毒素受体的表达增强，因此，内毒素受体可能参与肝星状细胞在肝脏炎症和纤维化中的作用。     

α-GalCer诱导急性肝损伤时肝内Kupffer细胞表型和功能的变化

背景:Kupffer细胞是肝内重要的免疫细胞,在天然免疫和适应性免疫中起重要作用。目的:研究α-GalCer诱导的急性肝损伤中肝内Kupffer细胞表型和功能变化。方法:将30只小鼠分为模型组和对照组,腹腔注射α-GalCer诱导小鼠急性肝损伤。行肝组织病理学检查,免疫组化法检测肝内F4/80阳性的Kupffer细胞的分布。胶原酶原位灌注、不连续密度梯度离心和选择性贴壁法分离正常和急性肝损伤小鼠的Kupffer细胞。real time-PCR法检测肝组织和Kupffer细胞肿瘤坏死因子(TNF)-α、于扰素γ(IFN-γ)、白细胞介素(IL)-10和Toll样受体(TLR)4mRNA表达。采用全自动生化仪测定血清ALT和AST水平。结果:α-GalCer腹腔注射引起小鼠局灶性肝细胞坏死、炎性细胞聚集,血清ALT、AST明显升高(P<0.05)。免疫组化法发现肝内F4/80阳性细胞明显增加、体积增大,并在肝组织炎症坏死处呈灶性聚集。胶原酶原位灌注分离的Kupffer细胞数量明显增加(P<0.01),肝组织和Kupffer细胞TNF-α、IFN-γ和IL-10 mRNA表达明显增加(P<0.05),而Kupffer细胞中TLR4 mRNA表达显著下降(P<0.05)。结论:在急性肝损伤中Kupffer细胞的抗炎因子IL-10表达增加和TLR4途径下调可能是Kupffer细胞维持机体免疫耐受、避免过度炎症的重要机制。     

内毒素性肝衰竭大鼠TLR4mRNA表达、血清肿瘤坏死因子-α及肝细胞凋亡的动态变化

目的 观察急性内毒素性肝衰竭大鼠肝组织中TLR4mRNA表达变化规律及其与血清肿瘤坏死因子-α水平、肝细胞凋亡的关系。方法雌性Wistar大鼠给予D氨基半乳糖／脂多糖同时腹腔注射，计算动物死亡率及生存时间，动态观察给药后4、8、12h肝功能、血清肿瘤坏死因子-α、肝组织TLR4mRNA表达及病理变化，以TUNEL法检测原位细胞凋亡，计算凋亡指数。结果80％大鼠死于急性肝衰竭，平均生存时间15．6h±1．8h，病理表现为肝脏大块或亚大块坏死。给药后4、8、12h血清TNF—α增高含量及肝细胞凋亡均增加，血清TNF—α变化早于肝细胞凋亡指数的增加，肝组织TLR4mRNA的表达与血清TNF—α含量呈正相关（r=0．709，P=0．000）。结论 内毒素通过单核吞噬系统TLR4介导TNF—α大量产生，激活炎症级联反应并诱导肝细胞凋亡是内毒素性肝衰竭的重要病理机制之一，阻断肝内外单核吞噬系统TLR4介导的的生理学作用，可能会对内毒素性肝衰竭起到一定防治作用。