抑制性寡脱氧核苷酸的生物学效应及研究进展

DNA对于机体免疫系统具有很多复杂的作用。存在于细菌DNA中的刺激性CpG基序能够促进机体免疫细胞分泌多种细胞因子,使机体产生偏向Th1方向的免疫应答,而抑制性寡脱氧核苷酸(oligodeoxynucleotide,ODN)可以选择性阻断刺激性CpG诱导的免疫激活作用。抑制性ODN按其结构不同大致分为三类,它可能通过影响细胞对CpG-S的结合及摄取、降低CpG-S特异性受体TLR9的表达发挥抑制作用。本综述主要介绍抑制性ODN的结构特征、作用机制和它在一些疾病中发挥的作用。     

抑制性寡脱氧核苷酸的生物学效应及研究进展

DNA对于机体免疫系统具有很多复杂的作用。存在于细菌DNA中的刺激性CpG基序能够促进机体免疫细胞分泌多种细胞因子,使机体产生偏向Th1方向的免疫应答,而抑制性寡脱氧核苷酸（oligodeoxynucleotide,ODN）可以选择性阻断刺激性CpG诱导的免疫激活作用。抑制性ODN按其结构不同大致分为三类,它可能通过影响细胞对CpG-S的结合及摄取、降低CpG-S特异性受体TLR9的表达发挥抑制作用。本综述主要介绍抑制性ODN的结构特征、作用机制和它在一些疾病中发挥的作用。     

NF-κB圈套寡脱氧核苷酸技术的发展和应用

NF κB是一种重要的核转录因子 ,可被多种刺激因素激活 ,并转位至细胞核 ,与相应的靶基因结合 ,启动基因转录。NF κB的靶基因包括编码细胞因子、粘附分子、诱导型一氧化氮合酶等的基因 ,因此与多种炎性疾病、自身免疫性疾病和肿瘤的发生有关。人工合成的双链NF κB圈套寡脱氧核苷酸含有NF κB结合位点 ,可与游离的NF κB结合 ,从而圈套了NF κB ,阻止其活化。NF κB圈套寡脱氧核苷酸已成功用于多种疾病的发病机制及治疗学研究 ,具有广泛的应用前景     

肝损伤模型小鼠高迁移率族蛋白-1的表达

将刀豆蛋白A(Con A)经尾静脉注射入雄性Balb/C小鼠,建立T细胞介导的Con A急性肝损伤小鼠模型,检测模型小鼠不同时间点血清中高迁移率族蛋白1(HMGB1)及肝组织HMGB1 mRNA的表达水平,并与血清中TNF-α进行对比.实验显示:在Con A注射后0~3h,小鼠血清中的未能检测出HMGB1蛋白特异带:但在4h后,检测出一条微弱的HMGB1蛋白特异带;在6~36h,均检测出一条清晰的HMGB1蛋白特异带,在8~12 h处于一个高水平状态.而正常对照组小鼠血清中未能检测HMGB1蛋白-与HMGB1动力学曲线不同.血清中TNF-α水平在Con A注射后2h就达到峰值,4h后迅速下降,8h恢复到正常范围.Con A小鼠肝细胞中HMGB1 mRNA的表达在Con A注射1h后即达到峰值,是对照组的2.4倍,之后迅速回落,3-12h均低于对照组水平(0.5~0.8倍),24h后逐渐恢复正常水平.初步揭示HMGB1在Con A小鼠急性肝损伤中可能发挥重要作用,血清中HMGB1蛋白与TNF-α相比,呈现出迟发与长效的特点,HMGB1给肝细胞造成损伤有足够强度和效应时间.     

阿魏酸对刀豆蛋白A诱导的小鼠免疫性肝损伤的保护作用

探讨阿魏酸(ferulic acid, FA)对刀豆蛋白A (concanavalin A, Con A)诱导的免疫性肝损伤是否有保护作用。将雄性Balb/c小鼠随机分成6组:空白组、阿魏酸对照组(100 mg/kg)、模型组(15 mg/kg Con A)、低剂量阿魏酸干预组(10 mg/kg)、中剂量阿魏酸干预组(30 mg/kg)、高剂量阿魏酸干预组(100 mg/kg)。阿魏酸灌胃后,尾静脉注射刀豆蛋白A 15 mg/kg,24 h后,取其血和肝组织进行检测。与空白组比较,模型组中苏木精和伊红染色(HE)坏死区域明显增加,丙氨酸氨基转移酶(ALT)和天门冬氨酸氨基转移酶(AST)水平、半胱天冬氨酸酶3 (Caspase-3)活性、肿瘤坏死因子-α(TNF-α)和干扰素-γ(IFN-γ)水平、CD4~+T细胞中CD69的表达都明显增高。与模型组相比,阿魏酸干预组的ALT和AST水平明显降低,呈剂量依赖性,HE坏死区域减少,Caspase-3活性、TNF-α和IFN-γ水平、CD4~+T细胞CD69的表达都明显降低,且具有统计学意义。表明阿魏酸对刀豆蛋白A诱导的免疫性肝损伤有保护作用,其机制可能是抑制CD4~+T淋巴细胞的活化、细胞因子的释放,减轻炎症和肝组织的凋亡。     

反义c-fos寡脱氧核苷酸对hCG诱导大鼠黄体细胞孕酮和雌二醇生成的影响

采用离体孵育大鼠黄体细胞的方法,观察了反义c-fos寡脱氧核苷酸(反义c-fos ODN)对hCG诱导的黄体细胞孕酮(P)和雌二醇(E     

海兔素对刀豆蛋白A诱导的化学性肝损伤保护作用

目的:探讨海兔素对刀豆蛋白A诱导的化学性肝损伤保护作用。方法:雄性Wistar大鼠随机分为4组。模型组与海兔素组给予15 mg/kg刀豆蛋白A尾静脉注射每周一次,制作化学性肝损伤模型,模型制作成功后,正常对照组、模型组每日给予大豆油灌胃,海兔素低、高剂量组给予100、150 mg/kg·d海兔素+大豆油灌胃。实验持续8周后,禁食12 h,处死大鼠。HE染色观察肝组织形态学改变;Masson Trichrome及天狼星红染色观察肝组织纤维化状况;全自动生化分析仪检测血清ALT、AST及LDH水平;ELISA实验测定血清TNF-α和TGF-β1水平。结果:与正常对照组相比,模型组大鼠肝小叶结构模糊紊乱,纤维组织增生明显,可见灶状坏死及炎性细胞浸润,胶原纤维明显增多,胶原指数明显升高。血清中ALT、AST、LDH及TNF-α和TGF-β1水平显著升高(P0.05)。海兔素干预后,肝小叶病变程度较模型组明显减轻,染色胶原显著减少,纤维增生明显改善,血清中ALT、AST、LDH及TNF-α和TGF-β1水平较模型组显著降低(P0.05),海兔素高剂量组与低剂量组相比,肝脏病变改善程度更为明显(P0.05)。结论:海兔素对刀豆蛋白A诱导的化学性肝损伤具有一定保护作用,其机制可能与下调TNF-α、TGF-β1水平有关。     

流体力学注射IL-35质粒对ConA诱导小鼠肝损伤的保护作用

目的:观察流体力学注射白细胞介素35(IL-35)质粒对刀豆蛋白A(ConA)诱导的小鼠肝损伤的干预效果。方法:通过流体力学注射将pcDNA3.1-IL-35导入C57BL/6小鼠体内,对照组注射pcDNA3.1。24h后,以ConA(15mg/kg)尾静脉注射建立小鼠肝损伤模型,检测血清ALT活性和肝组织病理变化。结果:流体力学注射pcDNA3.1-IL-3524h后,肝组织有IL-35mRNA和蛋白的表达。与对照组相比,pcDNA3.1-IL-35预处理组小鼠血清ALT水平明显降低,肝组织病理损伤明显减轻。结论:流体力学注射IL-35质粒对ConA诱导的小鼠肝损伤具有保护作用。     

雷公藤甲素对Con A诱导小鼠急性肝损伤的保护作用及机制

摘要 目的：探究雷公藤甲素（Triptolide）对刀豆蛋白A（Concanavalin, Con A）诱导的小鼠急性肝损伤的保护机制。方法：雄性BALB/c小鼠30只,随机等分为正常对照组、Con A模型组和雷公藤甲素治疗组。通过尾静脉注射Con A构建小鼠急性肝损伤模型。微孔板法检测血清谷丙转氨酶（ALT）和谷草转氨酶（AST）水平,HE染色观察肝组织病理变化,免疫组化、实时荧光定量PCR（RT-qPCR）和酶联免疫吸附试验（ELISA）检测肝组织及血清中细胞因子水平。结果：与正常对照组比较,Con A诱导急性肝损伤小鼠血清ALT、AST水平显著增高（P<0.05）,肝组织呈局灶性炎性浸润、坏死。与Con A模型组比较,雷公藤甲素治疗组小鼠血清ALT、AST水平显著下降（P<0.05）;肝组织病理程度明显减轻;肝组织中CD4⁺T细胞的浸润降低,促炎细胞因子（IFN-γ、TNF-α、IL-1β、IL-2）的水平显著降低（P<0.05）。结论：雷公藤甲素可以通过抑制CD4⁺T细胞向肝脏募集,下调IFN-γ、TNF-α、IL-1β、IL-2的表达,有效防治Con A诱导的急性免疫性肝损伤。     

脂连素对小鼠急性肝损伤的保护作用

目的观察脂连素对刀豆蛋白A（ConA）所致小鼠急性肝损伤的干预作用,并对其机制进行初步探讨。方法雄性BALB／C小鼠17只,随机分为3组：ConA组6只：尾静脉注射ConA。脂连素组5只：在静脉注射ConA前腹腔内注射脂连素。对照组6只：尾静脉注射生理盐水。注射ConA后8小时留取血清检测各组ALT和TNF-α水平,肝组织进行HE染色,并检测NF-κB活性及肝细胞凋亡率。结果HE染色可见ConA组肝细胞水肿、变性,肝组织内淋巴细胞浸润、淤血等,脂连素组上述病理变化减轻（P〈0．01）。脂连素组ALT和TNF-α水平、NF-κB活性、肝细胞凋亡率均低于ConA组（P〈0．01或P〈0．05）。结论脂连素具有抗炎作用,其机制可能与减少TNF-α的产生、抑制肝组织NF-κB活性及抗肝细胞凋亡有关。     

The Protective Effect of Esculentoside A on Experimental Acute Liver Injury in Mice

Inflammatory response and oxidative stress are considered to play an important role in the development of acute liver injury induced by carbon tetrachloride (CCl₄) and galactosamine (GalN)/lipopolysaccharides (LPS). Esculentoside A (EsA), isolated from the Chinese herb phytolacca esculenta, has the effect of modulating immune response, cell proliferation and apoptosis as well as anti-inflammatory effects. The present study is to evaluate the protective effect of EsA on CCl₄ and GalN/LPS-induced acute liver injury. In vitro, CCK-8 assays showed that EsA had no cytotoxicity, while it significantly reduced levels of TNF-α and cell death rate challenged by CCl₄. Moreover, EsA treatment up-regulated PPAR-γ expression of LO2 cells and reduced levels of reactive oxygen species (ROS) challenged by CCl₄. In vivo, EsA prevented mice from CCl₄-induced liver histopathological damage. In addition, levels of AST and ALT were significantly decreased by EsA treatment. Furthermore, the mice treated with EsA had a lower level of TNF-α, Interleukin (IL)-1β and IL-6 in mRNA expression. EsA prevented MDA release and increased GSH-Px activity in liver tissues. Immunohistochemical staining showed that over-expression of F4/80 and CD11b were markedly inhibited by EsA. The western bolt results showed that EsA significantly inhibited CCl₄-induced phosphonated IkBalpha (P-IκB) and ERK. Furthermore, EsA treatment also alleviated GalN/LPS-induced acute liver injury on liver enzyme and histopathological damage. Unfortunately, our results exhibited that EsA had no effects on CCl₄-induced hepatocyte apoptosis which were showed by TUNEL staining and Bax, Caspase-3 and cleaved Caspase-3 expression. Our results proved that EsA treatment attenuated CCl₄ and GalN/LPS-induced acute liver injury in mice and its protective effects might be involved in inhibiting inflammatory response and oxidative stress, but not apoptosis with its underlying mechanism associated with PPAR-γ, NF-κB and ERK signal pathways.     

藻蓝蛋白复合物对酒精性肝损伤的保护作用

本文对藻蓝蛋白复合物保护化学性肝损伤的功效学进行了研究.以Wistar大鼠建立酒精性肝损伤模型,将藻蓝蛋白复合物分为高、中、低三个剂量组,以联苯双酯作为阳性对照组,灌胃给药42 d,分别测定血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、血清丙二醛(MDA)、谷胱甘肽(CSH)、肝匀浆丙二醛(MDA)和谷胱甘肽(GSH)的含量,并对肝脏切片进行病理检查.结果表明:藻蓝蛋白复合物对血清ALT、AST具有显著的抑制作用,显著拮抗肝脏MDA的升高,显著提高肝脏GSH-Px含量.出现肝细胞浊肿、脂肪变性、点状坏死的大鼠数目极少.从而表明藻蓝蛋白复合物具有显著的保护酒精性肝损伤的功效.     

Effects of Kupffer cell-depletion on Concanavalin A-induced hepatitis

TNF-α, IFN-γ, IL-4, and MIP-2 are known to be involved in Con A-induced hepatitis. Although Kupffer cells are reportedly involved in TNF-α production, it is largely unknown whether or not Kupffer cells also play a role in the production of other cytokines, such as IFN-γ, IL-4, and MIP-2. In this study we examined the liver injury and the levels of plasma cytokines, including above four cytokines, KC, and IL-10 in Kupffer cell-depleted mice obtained through administration of liposome-encapsulated dichloromethylene bisphosphonate. The liver injury was significantly suppressed in Kupffer cell-depleted mice, as assessed as to the plasma ALT level and histochemistry. The cytokine levels were also significantly suppressed in such mice except for those of IFN-γ, which was slightly suppressed at 12 h, and IL-10, which was not significantly suppressed at any time. Apoptosis was also significantly suppressed in such mice, as found immunohistochemically with anti-ssDNA Ab. Taken together, these results suggest that Kupffer cells are involved in the production of MIP-2, KC, IL-4, and TNF-α in Con A-induced hepatitis, thereby contributing to the liver injury either directly or indirectly.     

七氟烷对培养的小鼠小胶质细胞炎症因子表达的影响

目的：探讨七氟烷对培养的小鼠小胶质细胞中炎症因子表达的影响。方法：取新生（2~3 天）C57BL/6小鼠,分离小胶质细胞, 将其随机分为4 组（n=10）：对照组（Control）;七氟烷组（Sevoflurane）;NF-资B抑制剂组（PDTC）;NF-kB 抑制剂+七氟烷组 （PDTC+Sevoflurane）。用Drager 麻醉机向Sevoflurane 组PDTC+Sevoflurane 组培养的小胶质细胞盒内释放21%O2,5%CO2,4.1% 七氟烷的气体,用气体分析仪持续监测各组的浓度。应用Iba-1 的免疫荧光染色法对小鼠小胶质细胞进行纯度鉴定。分别在于给 七氟烷后2 h、4 h 和6 h 时采用免疫印迹分析技术检测两组小胶质细胞IL-6 和TNF-alpha的表达水平和NF-kB 的活性。 PDTC+Sevoflurane 组在给七氟烷前一小时给予PDTC,采用ELISA 技术和免疫印迹分析技术检测各组小胶质细胞IL-6 和 TNF-alpha的浓度和NF-kB 的表达。结果：免疫印迹显示七氟烷组细胞中IL-6、TNF-alpha水平和NF- kB 的激活水平升高;PDTC降低了 七氟烷作用后核内NF-kB 的表达,减弱了IL-6和TNF-alpha水平的升高作用。结论：七氟烷可通过激活NF-kB信号通路,进一步激 活培养的小鼠小胶质细胞中炎症因子的表达。     

杭白菊保肝作用研究

本实验对杭白菊的保肝作用进行了研究。以四氯化碳诱导的小鼠急性肝损伤为模型,将杭白菊乙醇提取物和多糖部分分为高、中、低三个剂量组,以联苯双酯为阳性对照,灌胃给药8 d,分别测定血清谷丙转氨酶(GPT)、谷草转氨酶(GOT)、肝匀浆丙二醛(MDA)、肝匀浆超氧化物歧化酶(SOD)。结果表明:杭白菊乙醇提取物和多糖部分高剂量组对血清GPT、GOT具有显著的抑制作用,杭白菊乙醇提取物高剂量组显著拮抗肝脏MDA的升高。表明杭白菊有保护四氯化碳所致肝损伤的作用。     

Preventive Effect of Halofuginone on Concanavalin A-Induced Liver Fibrosis

Halofuginone (HF) is an active component of extracts derived from the plant alkaloid febrifugine and has shown therapeutic promise in animal models of fibrotic disease. Our main objectives were to clarify the suppressive effect of HF on concanavalin A (ConA)-induced liver fibrosis. ConA injection into the tail vein caused a great increase in the serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, while orally administration of HF significantly decreased the levels of the transaminases. In addition, the levels of hyaluronic acid (HA), procollagen III (PCIII) and TGF-β1 in the serum and collagen I, α-SMA, tissue inhibitors of metalloproteinase 2 (TIMP2) and Smad3 in the liver tissue were significantly lowered with the treatment of HF. Histological examination also demonstrated that HF significantly reduced the severity of liver fibrosis. Since ConA-induced liver fibrosis is caused by the repeated activation of T cells, immunomodulatory substances might be responsible for the suppressive effect of HF. We found that the production of nuclear factor (NF)-kB in the serum was increased in ConA-treated group, while decreased significantly with the treatment of HF. The changes of inflammatory cytokines tumor necrosis factor (TNF-α), IL-6 and IL-1β in the serum followed the same rhythm. All together, our findings indicate that orally administration HF (10ppm) would attenuate the liver fibrosis by suppressing the synthesis of collagen I and inflammation-mediated liver injury.