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.

五灵胶囊对刀豆蛋白A诱导自身免疫性肝炎小鼠的保护作用

目的探讨五灵胶囊对自身免疫性肝炎(AIH)小鼠的保护作用。方法小鼠随机分为对照组、AIH模型组、五灵胶囊低剂量组(0.5 g·kg^(-1)·d^(-1))、五灵胶囊中剂量组(1.0 g·kg^(-1)·d^(-1))、五灵胶囊高剂量组(2.0 g·kg^(-1)·d^(-1)),每组10只。五灵胶囊各剂量组按10 mL/kg的体积灌胃给予五灵胶囊混悬液,每天1次;对照组和AIH模型组灌胃给予等体积生理盐水。给药14 d后,AIH模型组和五灵胶囊各剂量组小鼠尾静脉注射刀豆蛋白A(20 mg/kg),注射8 h后收集血清、肝脏和脾脏。采用全自动生化分析仪检测血清丙氨酸转氨酶(ALT)和天冬氨酸转氨酶(AST)水平,用H-E染色观察肝组织病理结构,用ELISA法测定肝组织中IL-6、IL-4和TNF-α含量,用qPCR法测定肝组织中IL-6、IL-4、TNF-α、Toll样受体4(TLR4)和NF-κB mRNA的相对表达量,用免疫荧光法分析肝组织中NF-κB p65蛋白表达和核移位情况。结果与对照组相比,AIH模型组小鼠肝脏形态结构异常,血清ALT和AST水平升高,肝组织中IL-4、IL-6和TNF-α含量升高,肝组织中IL-6、IL-4、TNF-α、TLR4和NF-κB mRNA的相对表达量上调,NF-κB p65的入核增加。五灵胶囊明显改善AIH模型小鼠的肝脏病理结构,降低血清ALT和AST水平,降低肝组织中IL-4、IL-6和TNF-α含量及TLR4、NF-κB、IL-4、IL-6 mRNA的相对表达量,并抑制NF-κB p65的入核激活。结论五灵胶囊对AIH小鼠具有明显的保护作用,其机制可能与TLR4/NF-κB信号通路有关。

Notch signaling mediated by TGF-β/Smad pathway in concanavalin A-induced liver fibrosis in rats

AIM To explore the exact interaction between Notch and transforming growth factor(TGF)-β signaling in liver fibrosis. METHODS We established a rat model of liver fibrosis induced by concanavalin A. Peripheral blood mononuclear cells(PBMCs) were isolated from the modeled rats, and cultured with γ-secretase inhibitor DAPT and TGF-β inhibitor for 24 h. The m RNA levels of Notch and TGF-β signaling were detected by quantitative real-time polymerase chain reaction. Expression of Notch and TGF-β proteins was analyzed by western blotting.RESULTS Compared to control rats, Notch and TGF-β signaling was activated in PBMCs of model rats. Administration of DAPT and TGF-β inhibitor suppressed Notch and TGF-β signal transducer in PBMCs of model rats. DAPT reduced m RNA and protein expression of TGF-β signaling, such as TGF-β1 and Smad3. TGF-β inhibitor also downregulated Notch1, Hes1 and Hes5, and m RNA and protein expression of the Notch signaling pathway.CONCLUSION Notch and TGF-β signaling play a role in liver fibrosis. TGF-β signaling upregulates Notch signaling, which promotes TGF-β signaling.

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.

Interleukin-22 contributes to liver regeneration in micewith concanavalin A-induced hepatitis after hepatectomy

AIM: To investigate the therapeutic effects and mechanisms of interleukin(IL)-22 in liver regeneration in mice with concanavalin A(Con A)-induced liver injury following 70% hepatectomy.METHODS: Mice were injected intravenously with Con A at 10 μg/g body weight 4 d before 70% hepatectomy to create a hepatitis model, and recombinant IL-22 was injected at 0.125 μg/g body weight 30 min prior to 70% hepatectomy to create a therapy model. Control animals received an intravenous injection of an identical volume of normal saline.RESULTS: IL-22 treatment prior to 70% hepatectomy performed under general anesthesia resulted in reductions in the biochemical and histological evidence of liver injury, earlier proliferating cell nuclear antigen expression and accelerated recovery of liver mass. IL-22 pretreatment also significantly induced signal transducer and activator of transcription factor 3(STAT3) activation and increased the expression of a variety of mitogenic proteins, such as Cyclin D1. Furthermore, alpha fetal protein m RNA expression was significantly elevated after IL-22 treatment.CONCLUSION: In this study, we demonstrated that IL-22 is a survival factor for hepatocytes and prevents and repairs liver injury by enhancing pro-growth pathways via STAT3 activation. Treatment with IL-22 protein may represent a novel therapeutic strategy for preventing liver injury in patients with liver disease who have undergone hepatectomy.

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.

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.

A comparative study of changing patterns of concanavalin A-binding proteins in early stage of cholesterol gallstone

IM To elucidate the importance and the changing patterns of biliary concanavalin Abinding proteins (CPs) in the early stage of cholesterol gallstone.METHODS CPs concentrations and nucleation activities were measured by lectin affinity chromatography in biles of patients with cholesterol gallstone, pigment gallstone, gallbladder cholesterosis and nonbiliary diseases.RESULTS The concentrations of CPs were much higher in patients with cholesterol gallstone (039g/L±011g/L, n=36, P<001) or gallbladder cholesterosis (040g/L±009g/L, n=9, P<001) than in those with pigment gallstone (026g/L±012g/L, n=7) and/or nonbiliary diseases (027g/L±009g/L, n=10). Pronucleating activities were much stronger in patients with cholesterol gallstones (nucleation time ratio: 057±021, n=5, P<001 vs pigment gallstone and/or nonbiliary diseases) and gallbladder cholesterosis (nucleation time ratio: 044±023, n=5, P<001 vs pigment gallstone or nonbilliary diseases). The binding percentages of CPs to model biliary vesicles were also higher in patients with cholesterol gallstones (n=6) than those with pigment gallstones (n=6) (24%±09% vs 09%±05%, P<001).CONCLUSION Hypersecretion of CPs, especially those in vesicular phase may be the important changes in the early stage of cholesterol gallstone.

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.

Concanavalin A-induced changes in lysosomal morphology of macrophages under confocal microscope

Changes in lysosomal morphology of cultured mouse peritoneal macrophages after stimu1ation by Concanavalin A (Con A) were observed with a laser scanning confocal microscope (LSCM). A series of images were obtained including phase-contrast images, optical sectioning images, 3-dimensional reconstruction images. The changes of lysosomal fluorescence intensity and pH were measured. It was found that macrophage lysosomes were Cllstributed mainly at the periphery of the cells in resting conditions, the lysosomal area containing fluorescence probe became markedly enlarged after stimulation by Con A for 30 min, and the fluorescence intensity in the medium increased about 15 min after suggesting that Con A could induce outflow of the fluorescence probe within the macrophage lysosomes. The lysosomal pH rose from 4. 6 to 5. 7 in 7 min after Con A was added, and maintained at that level hereafter.

Effects of interleukin-18 and Anti-interleukin-18-mAb on Experimental immunological Liver Fibrosis induced by Repeatedly Administered Concanavalin A and its Mechanism

Objective To explore the prevention of IL-18 or anti-IL-18-m Ab to the immune liver fibrosis model induced by repeated injection of concanavalin A in BALB/c mice and its mechanism.Methods Total of 120 BALB/c mice were divided into four groups, control group mice(Ga) were injected weekly with normal saline, concanavalin A group was divided into Gb, Gc, Gd. All mice were injected with concanavalin A(15 mg/kg) once a week. Moreover, Gc, Gd mice were injected weekly with IL-18(7.5 mg/kg) and anti-IL-18-m Ab(10 mg/kg) 2 hours before treatment with concanavalin A, respectively. Twenty-four hours after concanavalin A challenge at 1, 5, 12 and 20 weeks, 3 mice were killed by vena orbitalis, repectively. The sera were storaged at 4℃ for detecting of up TNF-α and IFN-γ by ELISA. The liver of mice in different groups were excised and fixed in 10% formalin for HE staining and Masson staining or frozen in liquid nitrogen for immunohistochemical staining for α-SMA. After extracting of total RNA from liver tissue, MMP-2 and TIMP-1A messenger RNA were amplified by reverse transcription polymerase chain reaction(PCR). Products were electrophoresed on agrose gel containing ethidium bromide and visualized under ultraviolet light. Densitometric RT-PCR data were standardized with β-actin signals. Results After experiment, the number of dead mice of Ga, Gb, Gc and Gd were 0, 6, 15 and 3, respectively. There were significant difference on each group(P < 0.05). At the fifth week of experiment, hepatocellular necrosis in IL-18 administered group mice had become widespread throughout the lobule. Evidence of liver fibrosis was observed during this period. However, at the twelfth week of experimemt, bridging fibrosis and large fibrosis strip in the parenchyma with hepatocellular necrosis was detectable in Gb, but at twentieth week, only the small fibrosis strip had been found in anti-IL-18-mA b administered group mice by HE staining and Masson staining. The serum levels of TNF-α and IFN-γ in IL-18 administered group were higher than that in concanavalin A group and anti-IL-18 administered groups(P < 0.05). Moreover, immunohistochemical staining for α-SMA indicated that the semi-quantu scores in IL-18 administered group were more than concanavalin A group and anti-IL-18-mA b administered groups(P < 0.05). MMP-2-mR NA, TIMP-1- mR NA expression levels increased signifigantly compared with concanavalin A group and anti-IL-18-mA b administered group(P < 0.05).Conclusions The immune liver fibrosis model induced by repeated injection of concanavalin A in BALB/c mice could be worsened by IL-18 administration and block by anti-IL-18 mA b administraion.

羟基红花黄色素A对实验性自身免疫性肝炎小鼠的保护作用

目的 利用刀豆蛋白A(concanavalin A,Con A)诱导的肝损伤小鼠模型,研究羟基红花黄色素A(hydroxylsafflor yellow A,HSYA)对实验性自身免疫性肝炎小鼠的保护作用。方法 36只BALB/c小鼠随机分为6组,Sham组、Con A组、HSYA低剂量组(5 mg/kg)、HSYA中剂量组(10 mg/kg)、HSYA高剂量组(20 mg/kg)、Sham+HSYA高剂量组(20 mg/kg),每组小鼠各6只。将各组小鼠称质量并记录,通过腹腔注射给药的方式对其进行3 d HSYA预处理,处死小鼠前12 h,尾静脉注射Con A,制作实验性自身免疫性肝炎小鼠模型,最终以二氧化碳吸入法处死小鼠并取材备用。使用全自动生化分析仪检测各组小鼠血浆AST和ALT水平,并进行组间比较。肝组织进行苏木精-伊红染色,镜下观察肝脏组织学变化。应用ELISA检测血浆中TNF-α、 IL-17、IL-10水平。结果 Con A组小鼠体内TNF-α、 IL-17、IL-10水平(F=21.19、F=13.12、F=3.209,P均<0.05)及ALT、AST水平(F=274.33、F=214.91,P均<0.05)高于Shan组,并伴有肝细胞大片坏死。HSYA中剂量和HSYA高剂量组小鼠体内炎症因子水平及氨基转移酶水平低于ConA组,同时伴肝细胞坏死区域缩小。结论 Con A成功诱导小鼠肝组织损伤,HSYA对实验性自身免疫性肝炎小鼠具有保护作用。

灵芝酸A对刀豆球蛋白A诱导的急性免疫性肝损伤小鼠模型的影响及其作用机制

目的观察灵芝酸A(GA-A)对刀豆球蛋白A(ConA)诱导的小鼠自身免疫性肝炎(AIH)模型的治疗作用。方法将35只小鼠随机分为空白组(NC组)、模型组(ConA组)和GA-A低、中、高剂量治疗组(GA-A-L组、GA-A-M组、GA-A-H组),每组各7只小鼠。通过尾静脉注射ConA建立经典AIH小鼠模型,1 h后通过腹腔注射不同剂量GA-A治疗。应用蛋白质组学技术探究GA-A对肝细胞的保护机制,另外在体外用全反式维甲酸(ATRA)将HL-60细胞分化为dHL-60中性粒细胞来验证GA-A的作用机制。检测炎症(血清ALT和AST活性、HE染色及炎症相关基因)、凋亡(TUNEL染色)、中性粒细胞和中性粒细胞胞外陷阱(NET)标志物[髓过氧化物酶(MPO)、瓜氨酸化组蛋白3(CitH3)、Ly6G、游离双链DNA(dsDNA)]及p38磷酸化指标。计量资料两组间比较采用成组t检验;多组间比较采用单因素方差分析,进一步两两比较采用LSD-t检验。结果与NC组相比,ConA组小鼠血清ALT和AST水平显著增加(P值均<0.001)。与ConA组相比,GA-A治疗显著降低ALT和AST水平(P值均<0.01)。HE染色结果表明,ConA组小鼠肝脏发生明显坏死。GA-A治疗后显著减少肝坏死面积和TUNEL阳性肝细胞的数量(P值均<0.05)。另外,与ConA组相比,GA-A治疗后血清和肝组织中炎症因子IL-6、TNF-α和IFN-γ表达水平显著降低(P值均<0.05)。蛋白质组学分析提示,GA-A通过抑制NET的释放和p38 MAPK通路来减轻ConA诱导的急性免疫性肝损伤。小鼠肝组织免疫荧光染色结果显示,与ConA组相比,GA-A治疗组MPO阳性中性粒细胞的数量及Ly6G和CitH3阳性细胞的数量显著降低(P值均<0.01)。Western Blot及dsDNA结果显示,GA-A显著抑制小鼠肝组织及dHL-60细胞中的NET标志物dsDNA、CitH3以及p38磷酸化水平(P值均<0.05)。结论GA-A抑制p38 MAPK通路和NET释放减轻肝脏炎症反应和肝细胞死亡,从而减轻ConA诱导的急性免疫性肝损伤。本研究为GA-A通过调节嗜中性粒细胞功能治疗免疫性肝损伤提供了理论依据。

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。

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。

刀豆凝集素快速检测技术的研究现状及发展趋势

刀豆凝集素主要存在于刀豆中,是一种能与多糖、糖蛋白等物质发生特异性结合的植物凝集素。刀豆凝集素具有抗营养和抗虫害作用,是植物自我保护的重要环节,也是造成食用豆类食物中毒和过敏反应的主要原因。因此刀豆凝集素的检测对豆类蔬菜的育种、食用安全性评估等工作具有重要意义。详细介绍了新型刀豆凝集素快速检测技术的研究进展,包括基于纳米材料的生物传感器、免疫传感技术、糖传感技术和核酸适配体传感技术等。基于纳米材料的生物传感器具有较高的精度但是缺乏生物特异性;免疫传感技术改进了传统免疫法的检测速度但仍存在信号重复性差的问题;糖传感技术大幅提升了血凝法的特异性和检测精度,但无法区分糖特异性相同的凝集素。基于核酸适配体的检测技术具有优秀的检测精度、特异性和可重复性,还可通过化学修饰获得非天然核酸适配体进一步加强特异性,是未来刀豆凝集素快速检测的发展趋势。

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 A26.5 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(aspartateaminotransferase,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。

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。

鸭淋巴细胞转化试验(MTT法)最佳条件的研究

通过对培养温度、小牛血清及刀豆蛋白A(ConA)的浓度以及培养时间 4个参数的研究 ,确定了鸭淋巴细胞转化试验 (MTT法 )的最优培养条件。结果表明 ,采用 3 9.0℃、含 1 0 %小牛血清和 5μg/mLConA的RPMI1 64 0培养 66h可获得最大的OD570nm光吸值。

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。