Fermented Lentinus edodes extract containingα-glucan ameliorates concanavalin A-induced autoimmune hepatitis in mice

Autoimmune hepatitis(AIH)is a chronic inflammatory liver disease that threatens human health worldwide.The aim of this study was to detect the protective effect of a fermented Lentinus edodes extract containingα-glucan(FLA),in a concanavalin A(Con A)-induced AIH mouse model and to determine the underlying liver-protective mechanism.The results showed that compared with the model group,the level of proinflammatory cytokines in serum of FLA pretreated mice was significantly decreased,and the degree of inflammatory cell infiltration in liver,thymus and spleen was significantly reduced.Quantitative polymerase chain reaction,immunohistochemistry,and Western blotting showed that FLA pre-treatment inhibited the Con A-induced apoptosis of hepatocytes by down-regulating the expression of BAX and up-regulating the expression of BCL-2.Further research found that FLA may improve liver injury in mice by activating NRF2 signaling pathway and inhibiting TRAF6/NF-κB signaling pathway.Thus,FLA may improve liver injury in mice by shifting gut microbial composition to reduce the release of inflammatory cytokines in the serum and prevent the necrosis of hepatocytes.Up-regulation of NRF2 signaling pathway,down-regulation of TRAF6/NF-κB signaling pathway,and an increase in the relative abundance of Lactobacillus_johnsonii and Ligilactobacillus_murinus play a protective role in liver.

Stem cells from human exfoliated deciduous teeth ameliorate concanavalin A-induced autoimmune hepatitis by protecting hepatocytes from apoptosis

BACKGROUND Autoimmune hepatitis is a serious autoimmune liver disease that threatens human health worldwide,which emphasizes the urgent need to identify novel treatments.Stem cells from human exfoliated deciduous teeth(SHED),which are easy to obtain in a non-invasive manner,show pronounced proliferative and immunomodulatory capacities.AIM To investigate the protective effects of SHED on concanavalin A(ConA)-induced hepatitis in mice,and to elucidate the associated regulatory mechanisms.METHODS We used a ConA-induced acute hepatitis mouse model and an in vitro co-culture system to study the protective effects of SHED on ConA-induced autoimmune hepatitis,as well as the associated underlying mechanisms.RESULTS SHED infusion could prevent aberrant histopathological liver architecture caused by ConA-induced infiltration of CD3+,CD4+,tumor necrosis-alpha+,and interferon-gamma+inflammatory cells.Alanine aminotransferase and aspartate aminotransferase were significantly elevated in hepatitis mice.SHED infusion could therefore block ConA-induced alanine aminotransferase and aspartate aminotransferase elevations.Mechanistically,ConA upregulated tumor necrosisalpha and interferon-gamma expression,which was activated by the nuclear factor-kappa B pathway to induce hepatocyte apoptosis,resulting in acute liver injury.SHED administration protected hepatocytes from ConA-induced apoptosis.CONCLUSION SHED alleviates ConA-induced acute liver injury via inhibition of hepatocyte apoptosis mediated by the nuclear factor-kappa B pathway.Our findings could provide a potential treatment strategy for hepatitis.

A microarray analysis of early activated pathways in concanavalin A-induced hepatitis

Objective:To explore the mechanisms of fulminant hepatitis(FH) in the early stages,and to determine the critical pathways in its initiation and progression.Methods:Twelve BALB/c mice were divided into four groups:one group left as negative control and sacrificed immediately after injection of phosphate-buffered saline(PBS),and another three groups with concanavalin A(Con A) administration sacrificed at 1,3,and 6 h after injection.Affymetrix GeneChip Mouse 430 2.0 Array was employed to evaluate the expression profile of each of the 12 samples.Further analysis was done on the microarray data to extract the genes that were differentially expressed.Enrichment analysis was carried out to determine relevant pathways within which regulated genes were significantly enriched.Results:A total of 393,8354 and 11 344 differentially expressed genes were found,respectively,at three time points.During 0-1 h and 1-3 h,most of the pathways enriched with regulated genes were related to immune response and inflammation,among which Toll-like receptor(TLR) signaling and mitogen-activated protein kinase(MAPK) signaling appeared during both phases,while cytokine-cytokine receptor interaction,apoptosis,T cell receptor signaling,and natural killer(NK) cell-mediated cytotoxicity pathways emerged during the second phase.Pathways found to be significant during 3-6 h were mostly related to metabolic processes.Conclusion:The TLR signaling pathway dominates the early responses of Con A-induced FH in mice.It stimulates the production of type I cytokines,therefore recruiting and activating T/NK cells.Activated T/NK cells exert their cytotoxicity on hepatocytes through inducing death receptorintermediated apoptosis,resulting in liver injury.

Kupffer cells contribute to concanavalin A-induced hepatic injury through a Th1 but not Th17 type response-dependent pathway in mice

BACKGROUND:Increasing evidence suggests that a close interaction of Kupffer cells with T cells plays a central role in concanavalin A-induced hepatic injury in mice,but the underlying mechanisms remain obscure.The present study aimed to determine the relative roles of Th1 and Th17 type responses in concanavalin A-induced hepatic injury in mice, and to investigate whether or not Kupffer cells contribute to hepatic injury via a Th1 or Th17 type response-dependent pathway. METHODS:Immune-mediated hepatic injury was induced in C57BL/6 mice by intravenous injection of concanavalin A. Kupffer cells were inactivated by pretreatment with gadolinium chloride 24 hours before the concanavalin A injection.The interferon-gamma(IFN-γ)and interleukin-17(IL-17)pathways were blocked by specific neutralizing antibodies.Hepatic injury was assessed using serum transferase activity and pathological analysis.Expression of inflammatory cytokines within the liver was detected by real-time polymerase chain reaction and immunohistochemistry. RESULTS:Neutralization of IFN-γsignificantly attenuated concanavalin A-induced hepatic injury.However,neutralization of IL-17 failed to suppress the injury.Inactivation of Kupffer cells by gadolinium chloride pretreatment protected against concanavalin A-induced injury and significantly reduced hepatic cytokine levels including TNF-α,IL-6 and IFN-γbut not IL-17.CONCLUSION:Our findings suggest that Kupffer cells contribute to concanavalin A-induced hepatic injury via a Th1 type response-dependent pathway and production of inflammatory cytokines including TNF-α,IL-6 and IFN-γ.

Immune mechanisms of Concanavalin A model of autoimmune hepatitis

As a chronic inflammatory disease of the liver,the pathogenic mechanisms of autoimmune hepatitis (AIH) have not yet been elucidated,with prognosis and diagnosis remaining unsatisfied.Currently the only viable treatments of AIH are immunosuppressant application and liver transplantation.It is considered that lack of good animal AIH models is the main reason for the shortage of a simple and efficient cure.The Concanavalin A (Con A) model is a typical and well established model for investigating T-cell and macrophage dependent liver injury in mice,which closely mimics the pathogenesis mechanisms and pathological changes of patients,and is regarded as the best experimental model for AIH research so far.In this paper we eluci-dated the pathogenic mechanisms of AIH and the evolution of relative animal models.We go on to further focus on Con A-induced liver injury from the point of immunological mechanisms and the change of cytokine levels.Finally,we manifested the clinical significance of the AIH animal models and the challenges they would meet during their future development.

Immunomodulatory effect of schisandrae oil in mouse model of autoimmune hepatitis induced by concanavalin A

Objective:To study the immunomodulatory effect of schisandra oil (SCO) in mouse model of autoimmune hepatitis induced by concanavalin A (ConA). Methods: C57BL/6 mice were divided into control group, model group and SCO group. Mice in SCO group were given SCO at 5 mg/kg by intragastric administration every day for 7 days, followed by intravenous injection of ConA at 10 mg/kg. 10 hours after ConA injection, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured by the kits, the expression of inflammatory cytokines like interferon-γ(IFN-γ), interleukin-4 (IL-4), interleukin-17 (IL-17), tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β) and interleukin-6 (IL-6) in liver was detected by real-time quantitative PCR, and the T cell activation and IFN-γ expression in spleen and MLN were examined by flow cytometry. Results: Compared with control group, each indicator in model group were significantly higher. In SCO preventive treatment group, the levels of serum ALT, AST and LDH were significantly reduced (all P < 0.001), the expression levels of inflammatory cytokines in liver were downregulated, the T cell activation in spleen and MLN was inhibited (P = 0.006 and P = 0.008), the percentages of IFN-γ+ CD8+ and IFN-γ+ CD4+ T cells were decreased, and the frequencies of Th2 and Th17 cells in spleen and MLN were also decreased at the same time. Conclusion: SCO has a protective effect on immune liver injury by inhibiting the activation of T cells and reducing the expression of inflammatory cytokines, which reflects that SCO plays a role in the immunomodulation of autoimmune hepatitis, indicating that SCO is of great significance for the maintenance of autoimmune homeostasis.

根皮素对免疫性肝炎小鼠的保护作用及机制

目的观察根皮素(Phloretin,PHL)对自身免疫性肝炎(autoimmune hepatitis,AIH)小鼠的保护作用及调控机制。方法SPF级Balb/C小鼠32只,随机分为对照(Control)组、刀豆蛋白A(concanavalin A,ConA)模型组、PHL低剂量组和PHL高剂量组。造模处理24 h后提取小鼠血清及肝脏组织,ELISA法检测血清转氨酶及炎症因子;HE染色观察肝脏组织病理学变化;TUNEL染色检测肝细胞凋亡;qRT-PCR检测转录表达水平;免疫组化和Western-blot检测肝组织炎症因子、自噬与凋亡蛋白及TRAF6-JNK通路信号蛋白表达水平。结果与正常对照组相比,AIH小鼠血清转氨酶及炎症因子表达显著升高(P<0.001),病理学见肝组织结构被广泛破坏,肝细胞大面积坏死及炎性细胞浸润。与ConA组相比,PHL组血清转氨酶及炎症因子水平下降(P<0.05),肝细胞结构完整,肝细胞坏死面积减少(P<0.05)。此外,与ConA组相比,PHL显著下调肝组织促凋亡蛋白及自噬蛋白的表达(P<0.05),下调TRAF6-JNK信号通路激活(P<0.05)。结论PHL可能通过减轻AIH小鼠肝细胞自噬和肝细胞凋亡,缓解AIH小鼠高炎症负荷,发挥对AIH小鼠的保护作用,可能是通过TRAF6-JNK信号通路发挥作用。

环状RNA参与自身免疫性肝炎小鼠肝损伤的相关性分析

背景:自身免疫性肝炎的发病机制尚未明确阐明,环状RNA(CircRNAs)是RNA领域的一个研究热点,参与了许多自身免疫性疾病的发病,但CircRNAs在自身免疫性肝炎中的作用尚不清楚。目的:探讨CircRNAs与刀豆蛋白A诱导自身免疫性肝炎小鼠肝损伤的关系。方法:对前期微阵列技术筛选出差异表达的CircRNAs谱进行生物信息学分析,包括基因本体论(GO)及京都基因与基因组百科全书(KEGG)富集分析,探讨上述差异表达基因潜在的生物学功能。采用随机数字表法将12只C57BL/6小鼠分为正常组和模型组,每组6只,模型组通过尾静脉注射刀豆蛋白A建立自身免疫性肝炎模型,造模12 h后处死小鼠,提取小鼠肝脏及外周血,利用qRT-PCR技术验证部分CircRNAs的表达水平,通过比色法检测小鼠血清中肝损伤指标谷丙转氨酶和谷草转氨酶的水平,通过微孔板法检测小鼠肝脏中氧化应激指标丙二醛和NO的水平,并将肝损伤指标和氧化应激水平的相关性进行分析。结果与结论:①GO分析结果显示,表达上调CircRNAs的靶基因参与的生物过程主要为“SNARE复合装配的调节”(P=0.004)等,分子功能主要为“金属离子结合”(P=0.00029)等,主要富集在“CORVET复合体”(P=0.075)等细胞组分;表达下调circRNAs的靶基因参与的生物过程主要为“胰液分泌的负调节”(P=0.00042)等,分子功能主要为“转录激活因子活性”(P=0.025)等,主要富集在“膜外组分”(P=0.006)等细胞组分;②KEGG富集分析结果显示,表达上调CircRNAs的靶基因主要富集于“碱基切除修复”(P=0.026)等信号通路;③与正常组比较,模型组小鼠血清谷丙转氨酶和谷草转氨酶及肝组织中丙二醛和NO的水平升高(P<0.01),mmu-circ-0001520和mmu-circ-0001577的表达升高(P<0.05);④Spearman相关分析显示,mmu-circ-0001520和mmu-circ-0001577的表达与谷丙转氨酶、谷草转氨酶、丙二醛、NO存在正相关关系;⑤结果显示,CircRNAs的差异表达与自身免疫性肝炎小鼠肝损伤过程具有相关性,其中mmu-circ-0001520和mmu-circ-0001577有望成为自身免疫性肝炎诊断的生物标志物及治疗靶点。

The protective role of myeloid-derived suppressor cells in concanavalin A-induced hepatic injury

The mechanism underlying T cell-mediated fulminant hepatitis is not fully understood. In this study, we investigated whether myeloid derived suppressor cells （MDSCs） could prevent the concanavalin A （ConA）- induced hepatitis through suppressing T cell proliferation. We observed an increase in the frequencies of MDSCs in mouse spleen and liver at early stage of ConA treatment, implicating that the MDSCs might be involved in the initial resistance of mice against ConA- mediated inflammation. Subpopulation analysis showed that the MDSCs in liver of ConA-induced mice were mainly granulocytic MDSCs. Adoptive transfer of the bone marrow-derived MDSCs into ConA-treated mice showed that the MDSCs migrated into the liver and spleen where they suppressed T cell proliferation through ROS pathway. In addition, the frequencies of MDSCs in mice were also significantly increased by the treatment with immune suppressor glucocorticoids. Transfer of MDSCs into the regulatory T cell （Treg）- depleted mice showed that the protective effect of MDSCs on ConA-induced hepatitis is Treg-independent. In conclusion, our results demonstrate that MDSCs possess a direct protective role in T cell-mediated hepatitis, and increasing the frequency of MDSCs by either adoptive transfer or glucocorticoid treatment represents a potential cell-based therapeutic strategy for the acute inflammatory disease.

Elucidation of the hepatoprotective effect and mechanism of Melastoma dodecandrum Lour. based on network pharmacology and experimental validation

Objective:To systematically explore the effect and mechanism of melastomatis dodecandri herba(Melastoma dodecandrum Lour.)in the treatment of hepatitis based on network pharmacology.Method:We evaluated the hepatoprotective effects of M.dodecandrum in concanavalin A(Con A)-induced hepatitis in mice by assessing survival rate,histological analysis,serum transaminases,and related cytokines.Then the mechanism of action was predicted by a network pharmacology-based strategy.Based on the results,we measured the hepatic expression of related genes at mRNA level and proteins related to the phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt)and nuclear factorkappa B(NF-кB)pathways.Results:Our study results clearly demonstrated that M.dodecandrum pretreatment significantly alleviated liver injury.This was demonstrated by an increase in survival rate,decreased severity of liver damage,and reduced serum transaminase levels compared with those in the Con A group.Moreover,M.dodecandrum significantly reduced the serum levels of tumor necrosis factor-a,interleukin-6,and interferon-g and increased the liver levels of superoxide dismutase,which indicated that M.dodecandrum exhibits anti-inflammatory and antioxidant activities.On the basis of network pharmacology,50 nodes were selected as major hubs based on their topological importance.Pathway enrichment analyses indicated that the putative targets of M.dodecandrum mostly participate in various pathways associated with the anti-inflammation response,which implies the underlying mechanism by which M.dodecandrum acts on hepatitis.Real-time fluorescent quantitative PCR analysis showed that M.dodecandrum downregulates the mRNA expression of interleukin-6,Toll-like receptor 7,interleukin-1 receptor-associated kinase-4,NF-кB and tumor necrosis factor-a in liver tissues.Western blotting showed that M.dodecandrum pretreatment protected against inflammation through activating the PI3K-Akt pathway by upregulating phosphorylated Akt(p-Akt)expression and suppressing NF-кB activation by inhibiting the phosphorylation of IKK,IkBa,and p65.Conclusion:The present work demonstrated the hepatoprotective effects of M.dodecandrum by regulating the PI3K/Akt and NF-кB pathways in Con A-induced mice,which provide insights into the treatment of hepatitis using M.dodecandrum.

Immunomodulation and liver protection of Yinchenhao decoction against concanavalin A-induced chronic liver injury in mice

OBJECTIVE：This study investigated the immunoregulatory and protective roles of Yinchenhao decoction,a compound of Chinese herbal medicine,in a mouse model of concanavalin A（Con A）-induced chronic liver injury.METHODS：Female Bal B/c mice were randomly divided into 4 groups：normal control,Con A model,Con A model treated with Yinchenhao decoction（400 mg/kg,orally）,and Con A model treated with dexamethasone（0.5 mg/kg,orally）.All treatments were given once a day for 28 d.Except of the normal control,mice received tail vein injection of Con A（10 mg/kg）on days 7,14,21,and 28,at 1 h after treatment with Yinchenhao decoction or dexamethasone or saline to induce chronic liver injury.RESULTS：Repeated Con A injection induced chronic liver injury,which was evidenced by infl ammatory cell infi ltration and necrosis,increased serum alanine aminotranferease activities,decreased albumin levels,and an imbalanced expression of immunoregulatory genes in the liver tissues including signifi cantly enhanced interferon-γ,interleukin-4,monocyte chemotactic protein-1,and cluster of differentiation 163 m RNA levels,and reduced tumor necrosis factor-αand interleukin-6 m RNA levels.Treatment with Yinchenhao decoction signifi cantly reversed the Con A-induced changes in immunoregulatory gene expression in the liver tissues,reduced serum alanine aminotranferease activity,enhanced serum albumin level,and attenuated the extent of liver infl ammation and necrosis.Furthermore,Yinchenhao decoction did not result in hepatocyte degeneration and spleen weight loss that were observed in mice received long-term treatment with dexamethasone.CONCLUSION：Yinchenhao decoction treatment protected liver against the Con A-induced chronic liver damage and improved liver function,which were associated with the modulation of gene expression related to immune/infl ammatory response.

Human menstrual blood-derived stem cells alleviate autoimmune hepatitis via JNK/MAPK signaling pathway in vivo and in vitro

Autoimmune hepatitis(AIH)is a severe globally distributed liver disease that could occur at any age.Human menstrual blood-derived stem cells(MenSCs)have shown therapeutic effect in acute lung injury and liver failure.However,their role in the curative effect of AIH remains unclear.Here,a classic AIH mouse model was constructed through intravenous injection with concanavalin A(Con A).MenSCs were intravenously injected while Con A injection in the treatment groups.The results showed that the mortality by Con A injection was significantly decreased by MenSCs treatment and liver function tests and histological analysis were also ameliorated.The results of phosphoproteomic analysis and RNA-seq revealed that MenSCs improved AIH,mainly by apoptosis and c-Jun N-terminal kinase/mitogen-activated protein signaling pathways.Apoptosis analysis demonstrated that the protein expression of cleaved caspase 3 was increased by Con A injection and reduced by MenSCs transplantation,consistent with the TUNEL staining results.An AML12 co-culture system and JNK inhibitor(SP600125)were used to verify the JNK/MAPK and apoptosis signaling pathways.These findings suggested that MenSCs could be a promising strategy for AIH.

雄芍汤对刀豆蛋白A所致肝纤维化大鼠TGF-β1/p38MAPK信号通路的影响

目的:探讨雄芍汤抗刀豆蛋白A(ConA)所致大鼠肝纤维化的作用及其对TGF-β1/p38MAPK信号通路的影响。方法:50只Wistar雄性大鼠随机取10只作为正常组。40只大鼠尾静脉注射ConA-PBS溶液法复制大鼠肝纤维化模型。将38只造模成功大鼠随机分为模型组10只、雄芍汤组10只、雄芍汤加味组8只、扶正化瘀胶囊组10只。HE染色和Masson染色观察大鼠肝组织病理改变,检测大鼠肝功能指标(AST、ALT)、肝纤维化四项指标(HA、LN、PCⅢ、IV-C)、肝组织羟脯氨酸(HYP)含量。ELISA法检测大鼠血清α-平滑肌激动蛋白(α-SMA)、炎症因子(TNF-α、IL-1、IL-10)水平,Western blotting法检测TGF-β1、p38MAPK蛋白相对表达量,荧光定量PCR检测大鼠肝组织p38MAPK mRNA相对表达量,免疫组化法检测大鼠肝组织TGF-β1、NF-κBp65蛋白表达。结果:模型组大鼠肝组织可见炎症细胞浸润、肝细胞结构异常、纤维增生并异常沉积,各治疗组均能显著改善大鼠肝纤维化程度,减轻肝脏炎症,减少胶原纤维增生。与正常组比较,模型组大鼠血清AST、ALT、肝纤维化四项、α-SMA、TNF-α、IL-1水平明显升高(P<0.01),肝组织HYP含量、TGF-β1、p38MAPK、NF-κBp65蛋白相对表达量及p38MAPK mRNA相对表达量均明显升高(P<0.01);与模型组比较,各治疗组大鼠血清AST、ALT、肝纤维化四项、α-SMA、TNF-α、IL-1水平明显降低(P<0.01),肝组织HYP含量、TGF-β1、p38MAPK、NF-κBp65蛋白相对表达量及p38MAPK mRNA相对表达量均明显降低(P<0.01);与扶正化瘀胶囊组比较,雄芍汤组及雄芍汤加味组大鼠肝组织TGF-β1蛋白表达明显降低(P<0.05);除TGF-β1指标外,各治疗组上述其他指标之间差异无统计学意义(P>0.05);各组大鼠血清IL-10水平比较,差异无统计学意义(P>0.05)。结论:雄芍汤具有抗ConA所致大鼠肝纤维化、改善肝功能的作用,其抗肝纤维化的机制可能与抑制HSCs活化、减轻炎症反应、抑制TGF-β1/p38MAPK信号通路有关。雄芍汤和雄芍汤加味抑制肝组织TGF-β1蛋白表达作用优于扶正化瘀胶囊,而雄芍汤、雄芍汤加味和扶正化瘀胶囊抗肝纤维化作用及机制差异不明显。

刀豆素蛋白A诱导小鼠肝纤维化模型的建立

目的 建立小鼠的肝纤维化模型。方法 2 0只Balb c小鼠随机分 2组。实验组 (E组 )小鼠经尾静脉注射12 .5mg kg剂量的 1mol L刀豆素蛋白A(ConA) ,每周 1次 ,连续 6周 ;而对照组 (N组 )正常小鼠则相应地经尾静脉注射 2 5 0 μLPBS。每次注射ConA或PBS 2 4h后 ,经小鼠尾静脉取血检测ALT和AST。第 6次注射ConA一周后处死小鼠 ,取肝组织做HE染色及MassonTrichrome染色 ,显微镜下观察肝脏组织形态改变及胶原沉积情况。结果 与对照组比较 ,实验组小鼠的ALT和AST均明显升高 ,肝体积明显增大 ,表面不光滑 ,布满增生小结节。光镜下见肝组织结构紊乱 ,肝细胞坏死明显 ,有较多的淋巴细胞浸润。MassonTrichrome染色胶原明显增多。结论 反复静脉注射ConA可成功诱导建立小鼠肝纤维化模型。

刀豆蛋白A诱导Wistar大鼠肝纤维化模型的建立

目的:建立Wistar大鼠肝纤维化模型。方法:50只Wistar大鼠随机分成两组。实验组(E组)30只,经尾静脉注射12.5 mg/kg剂量的刀豆蛋白A(ConA),每周1次,10只大鼠在第4次注射1周后处死,其余20只8周后处死。正常对照组(N组)20只,大鼠经尾静脉注射300μl的PBS,第8次注射1周后处死。取大鼠肝脏计算肝脏指数并进行肝纤维化评分,做HE和Masson Trichrome染色,显微镜下观察肝脏的病理变化。取血清测ALT、AST、TP及ALB。结果:与对照组相比,实验组连续注射ConA 8周的大鼠ALT、AST显著升高,TP变化不明显,ALB及白球比显著降低。肝脏体积增大,肝脏指数增高,病理分析示明显纤维化。结论:反复尾静脉注射ConA可成功诱导Wistar大鼠肝脏纤维化模型的建立。

苦参碱对Con A性肝损伤小鼠IFN释放及肝组织病理改变的影响

目的:观察苦参碱对刀豆蛋白A(Con A)性肝损伤小鼠IFN-γ和TNF-α释放及肝组织病理改变的影响. 方法:NIH小鼠48只随机分为5组,分别为正常对照组,模型组,苦参碱大剂量组(25 mg/kg),苦参碱小剂量组(12.5 mg/kg)和联苯双酯治疗组.除正常对照组外,其他组于实验首日iv Con A 20 mg/kg,苦参碱大剂量组和小剂量组均采用尾iv给药,联苯双酯组按150 mg/kg 灌胃,每天1次,连续3 d,末次给药后4 h,再次iv Con A 20 mg/kg,8 h采血检测血浆IFN-γ和TNF-α含量、ALT活性,观察肝组织病理学变化. 结果:苦参碱大剂量组、小剂量纽小鼠IFN-γ和TNF-α含量均明显低于模型组(IFN-γ:25.5±6.1 vs 69.3±33.6 ng/L,26.5±2.5 vs 69.3±33.6 ng/L,t=4.0,4.0, P<0.01;TNF-α:49.1±11.9 vs 106.7±64.4 ng/L,52.9±5.2 vs 106.7±64.4 ng/L,t=2.9,2.9,P<0.01),但与联苯双酯组比较,差异无显著性意义(P>0.05);苦参碱大、小剂量组血浆ALT活性明显低于模型组(1 086.9 ±675.8 vs 2 477.2±529.9 nkat/L、1 121.9±957.4 vs 2 477.2±529.9 nkat/L,t=5.1,3.9,P<0.01),且可明显减轻肝细胞坏死及炎性细胞浸润的肝组织病理学改变,与模型组比较差异有显著性意义(P<0.05). 结论:苦参碱对刀豆蛋白A性肝损伤小鼠释放IFN-γ和TNF-α有明显的抑制作用.并可显著减轻肝组织病理改变.

FTY720对实验性肝纤维化小鼠肝损伤的保护作用

目的:观察FTY720对刀豆蛋白A(Con A)所致肝纤维化小鼠的保护作用,探讨其可能的作用机制。方法:采用刀豆蛋白A(Con A)建立小鼠肝纤维化动物模型,取40只BALB/C小鼠随机分为空白对照组、模型组、FTY720低剂量(1mg·kg-1)组和FTY720高剂量(4mg·kg-1)组,每组10只。测定各组小鼠血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)活性和肝脏指数,观察肝脏组织学病理变化。结果:FTY720低剂量组和高剂量组ALT、AST活性明显低于模型组(P<0.05或P<0.01)。光学显微镜观察,模型组有炎性细胞浸润,肝细胞坏死。Masson染色,模型组血管周围有明显纤维条束,肝小叶发生融合;与模型组比较,FTY720低剂量组和高剂量组损伤程度较轻,且随FTY720剂量增加肝组织损伤程度逐渐减轻。结论:FTY720对实验性肝纤维化小鼠的保护作用可能是通过降低ALT和AST活性,进而减轻肝脏损伤程度而延缓纤维化进程。

番茄红素对小鼠肝纤维化的治疗作用研究

目的研究番茄红素对腹腔注射Con A诱导昆明鼠肝纤维化的治疗作用。方法70只昆明鼠随机分组:正常对照组10只,PBS腹腔注射、生理盐水灌胃,第9周处死这组小鼠;番茄红素治疗组50只,Con A腹腔注射8周,第9周起番茄红素灌胃,于第1,2,3,4,5次灌胃后1周各处死10只;安慰剂治疗组10只第9周起生理盐水灌胃,第14周处死。小鼠处死后测血清ALT,AST,肝组织病理检查。结果正常对照组未出现肝纤维化;安慰剂治疗组有典型肝纤维化;治疗组治疗5周后肝纤维化消失。结论番茄红素对肝纤维化有治疗作用。

激活素结合蛋白在ConA诱导小鼠肝损伤时的表达及作用

目的:探讨激活素结合蛋白(Follistatin,FS)在刀豆蛋白A(ConcanavalinA,Con A)诱导肝损伤中的表达及作用。方法:尾静脉注射ConA诱导小鼠急性肝损伤,实时定量PCR检测FSmRNA表达,ELISA法检测FS及激活素A(Activin A)蛋白水平。结果:注射ConA后肝脏组织中FSmRNA表达水平在第三天明显下降,FS蛋白水平在第三天也呈下降趋势;而Activin A水平明显增高。注射FS中和内源性激活素A作用后,肝脏病理损伤程度明显减轻,血清转氨酶水平也显著低于ConA单纯诱导组。结论:在ConA诱导的急性肝损伤过程中激活素A-FS系统失平衡,应用FS阻断内源激活素A可以减轻ConA诱导的肝脏损伤,因此FS有可能成为治疗肝损伤性疾病的有效药物。

环孢菌素A阻断刀豆蛋白A诱发昆明小鼠肝损害的研究

观察环孢菌素A(CsA)能否阻断刀豆蛋白A (ConA)诱发小鼠肝损害 ,将昆明小鼠随机分为 5组 ,ConA自小鼠尾静脉注入制作肝损害实验动物模型 ,据ConA应用剂量不同而分别称为ConA 10mg/kg组 ,ConA 2 0mg/kg组和ConA 40mg/kg组 ;应用ConA前 15h和 1h皮下注射CsA(130mg/kg) ,该组称为CsA组 ;单独用PBS者为对照组。应用ConA后 8h取小鼠血测定ALT与TNF α ,并取肝组织行病理学观察。结果显示 ,ConA成功复制了小鼠特异性肝损害 ;CsA组小鼠血浆中ALT与PBS组相比无显著性差异 (P >0 .0 5 ) ,血浆TNF α亦无增高 ;病理学观察未发现肝脏内淋巴细胞及其他炎性细胞浸润。提示CsA可完全阻断ConA诱发小鼠肝损害 ,抑制T淋巴细胞活化和TNF