Loss-of-function mutations in caspase recruitment domain-containing protein 14 (CARD14) are associated with a severe variant of atopic dermatitis

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Human immunodeficiency virus 1 favors the persistence of infection by activating macrophages through TNF

Macrophages play a major role in HIV-1 persistence. In the present paper, we demonstrate that the absence of apoptosis in HIV-1-infected primary human monocyte-differentiated macrophages (MDM) correlates with an increase in anti-apoptotic (Bcl-2 and Bcl-x(L)) and a decrease in pro-apoptotic (Bax and Bad) proteins. This is associated with macrophage activation as shown by tumor necrosis factor (TNF) production and NF-kappaB activation upon infection. TNF production was shown to be involved in the upregulation of Bcl-2 and Bcl-x(L) because this increase was abolished by an anti-TNF anti-serum or an inhibitor of TNF synthesis. In parallel, inhibition of TNF production induced an increase in the number of apoptotic cells. Furthermore, using an inhibitor of NF-kappaB activation, we demonstrated that TNF-induced upregulation of Bcl-x(L) and Bcl-2 occurs, respectively, through a NF-kappaB-dependent and an NF-kappaB-independent pathway.     

Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling

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核转录因子-κB在缺氧预处理抑制心肌细胞凋亡中的作用

目的 :研究缺氧预处理 (hypoxicpreconditioning ,HPC)对于心肌细胞蛋白激酶C(PKC)和核转录因子κB (NF κB)表达的影响 ,及其在缺氧复氧诱导心肌细胞凋亡中的作用。方法 :在培养的SD乳鼠心肌细胞制作缺氧 /复氧 (H/R)模型 ,以荧光素染料Hoechst3 3 2 5 8测定心肌细胞凋亡率 ;制备心肌细胞蛋白提取物 ,以新PKCε亚型 (nPKCε)特异性抗体测定nPKCε相对蛋白含量 ;以抗NF κB抗体检测NF κB的表达 ;并以PKC抑制剂H7与心肌细胞预孵育后 ,观察H7对于HPC诱导的PKC和NF κB表达上调以及心肌细胞保护作用的影响。结果 :缺氧复氧造成心肌细胞凋亡 ,HPC可以降低心肌细胞H/R后凋亡率 ,并诱导nPKCε和NF κB表达上调 ;PKC抑制剂H7可以消除HPC诱导的PKC、NF κB表达上调和心肌细胞保护作用。结论 :HPC可以提高乳鼠心肌细胞对于H/R的耐受性 ,其机制涉及PKC介导的NF κB表达上调。     

C and V proteins of Sendai virus target signaling pathways leading to IRF-3 activation for the negative regulation of interferon-beta production

We here report a molecular basis for downregulation of interferon (IFN)-beta production by V and C proteins of Sendai virus (SeV). The infection of HeLa cells with SeV poorly induced IFN-beta even if the expression of C/C' was disrupted. In contrast, when the expression of C/C'/Y1/Y2 or V/W was disrupted, SeV infection strongly induced IFN-beta production and significantly activated the interferon regulatory factor (IRF)-3 pathway. The independent expression of C or V inhibited the double-stranded (ds) RNA- or Newcastle disease virus (NDV)-induced activation of IRF-3 and NF-kappa B, as well as the IFN-beta promoter. This inhibitory effect was also observed when Y1, Y2, or a C-terminal half fragment (aa 85-204) of C was independently expressed. Phosphorylation and homodimer formation of IRF-3 were suppressed not only in cells infected with SeV capable of expressing both C/C'/Y1/Y2 (or Y1/Y2) and V/W, but also in HeLa cells constitutively expressing Y1. These results suggest that C, Y1, Y2, and V block signaling pathways leading to IRF-3 activation to downregulate IFN-beta production.     

Protective effect of retinoic acid on interleukin-1 beta-induced cytotoxicity of pancreatic beta-cells

Cytokines produced by immune cells in pancreatic islets infiltrating are important mediators of beta-cell destruction in insulin-dependent diabetes mellitus. In this study, the effects of retinoic acid (RA) on cytokine-induced beta-cell dysfunction were examined. RA significantly protected interleukin-1 beta (IL-1) and interferon-gamma (IFN-gamma)-mediated cytotoxicity of rat insulinoma cell (RINm5F), and also reduced in IL-1 and IFN-gamma-induced nitric oxide (NO) production, which correlated well with reduced levels of the inducible form of NO synthase (iNOS) mRNA and protein. The molecular mechanism, by which RA inhibited iNOS gene expression, appeared to involve the inhibition of NF-kappa B activation. Our results suggest possible therapeutic value of RA for the prevention of diabetes mellitus progression.     

编码N端截短的IκBα突变体重组腺病毒的构建与鉴定

目的：通过去除N端丝氨酸32/36磷酸化位点，获得人胎盘组织IκBα突变体（IκBαM）基因，构建其复制缺陷型重组腺病毒（AdIκBαM），并进行体外表达和活性检测。方法:PCR定点克隆IκBαM基因（203-1 003 bp），亚克隆至pShuttle和pGEM-T，进行PCR、双酶切、DNA测序和同源性分析。将重组质粒pShuttle-IκBαM中含CMV启动子、IκBαM cDNA和PolyA信号的表达单元定向插入Ad5腺病毒载体，构建成重组腺病毒AdIκBαM，再经脂质体介导共转染293细胞进行包装。Western blotting检测AdIκBαM在293细胞中蛋白表达情况，电泳迁移率实验观察AdIκBαM抑制佛波酯诱导的ECV304细胞核因子κB（NF-κB）激活的作用。结果:成功克隆长801 bp的新型IκBαM基因，与GenBank中登陆的IκBα基因（接受号M69043）相应核苷酸序列一致。所制备的AdIκBαM滴度为4.0×1012 pfu/L。AdIκBαM介导IκBαM基因在293细胞中表达，并以剂量依赖性方式显著抑制佛波酯诱导的ECV304细胞NF-κB活化 。结论：AdIκBαM有效介导IκBαM基因表达并特异性抑制NF-κB活性，有望应用于哮喘的基因治疗。     

Pentoxifylline attenuates the development of hyperalgesia in a rat model of neuropathic pain

Pentoxifylline, a non-specific cytokine inhibitor, has shown to be beneficial in inflammatory pain in both experimental and clinical studies. The present study demonstrates for the first time, to our knowledge, the antihyperalgesic effect of pentoxifylline in the neuropathic pain using L5 spinal nerve transection rat model. In a preventive paradigm, pentoxifylline (12.5, 25, 50, or 100 mg/kg intraperitoneally) was administered systemically daily, beginning 1 h prior to nerve transection. Pentoxifylline (50, or 100 mg/kg i.p.) produced significant decrease in the mechanical and thermal hyperalgesia. However, pentoxifylline (100 mg/kg i.p.) did not influence the paw pressure thresholds and paw withdrawal latency in sham-operated rats. In order to understand the possible antinocicieptive effect of pentoxifylline in neuropathic pain, we examined the level of TNFα, IL-1β, IL-6 and IL-10 protein in the contralateral brain on day 7 post-transection. Pentoxifylline administration resulted in a dose-dependent reduction of the production of proinflammatory cytokines like TNFα, IL-1β and IL-6, and enhancement of IL-10. Furthermore, we investigated the activity of nuclear factor kappa B (NF-κB) in the contralateral brain on days 7 after surgery. In accordance with the change of proinflammatory cytokines, Pentoxifylline (50 or 100 mg/kg) significantly inhibited the activation of NF-κB in the brain. This research supports a growing body of literature emphasizing the importance of neuroinflammation and neuroimmune activation in the development of neuropathic pain states, and the potential preventive value of pentoxifylline in the treatment of neuropathic pain.     

降糖方对糖耐量异常大鼠糖脂代谢及骨骼肌组织IκB-α和NF-κBp65的影响

目的:探讨降糖方对糖耐量异常大鼠糖脂代谢及骨骼肌组织κB抑制蛋白α(IκB-α)、核转录因子肽p65(NF-κBp65)的影响。方法:SD大鼠随机分为正常组、模型组、盐酸二甲双胍组、降糖方低、高剂量组,采用高脂饮食喂养4周,链脲佐菌素(STZ)腹膜内注射建立糖耐量异常大鼠模型,治疗8周后,观察骨骼肌组织病理变化,测定空腹血糖(FPG)、血清胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL-C)、骨骼肌组织IκB-α mRNA、NF-κBp65 mRNA水平、骨骼肌组织白细胞介素-4(IL-4)、白细胞介素-12(IL-12)、肿瘤坏死因子-α(TNF-α)蛋白水平。结果:正常组大鼠骨骼肌组织结构正常,模型组骨骼肌排列紊乱、肌纤维断裂、可见明显炎症细胞浸润;盐酸二甲双胍及降糖方干预后,骨骼肌炎症细胞浸润减少,肌纤维排列趋于整齐。模型组大鼠FPG、FINS、HOMA-IR水平、血清TG、TC、LDL-C水平、骨骼肌IκB-α mRNA、NF-κBp65 mRNA和蛋白水平、骨骼肌组织IL-4、IL-12、TNF-α蛋白水平高于对...     

卡维地洛对高血压大鼠主动脉的保护作用

目的 :研究卡维地洛对核因子 κB(NF κB)、单核细胞趋化蛋白 1(MCP 1)在自发性高血压大鼠 (SHR)大血管中表达的影响 ,探讨其对血管保护的机制。方法 :18只雄性 12周龄SHR随机分为阳性组 ,卡维地洛组 ( 30mg/kg·d) ,美托洛尔组 ( 50mg/kg·d) ,灌喂 8周 ;另选同龄雄性WistarKyoto大鼠为阴性组 (n =6 )。用免疫组化法测各组主动脉NF κB、MCP 1的表达 ,ELISA法测血清MCP 1含量。结果 :与阴性组比较 ,阳性组主动脉组织中NF κB、MCP 1表达增加 (P<0 .0 1) ,且两者正相关 (r=0 .72 8,P <0 .0 1) ;血清MCP 1含量升高 1.6 4(P <0 .0 1)。 8周后 ,治疗组之间血压无明显差异 (P >0 .0 5) ,但卡维地洛更显著抑制NF -κB、MCP 1表达 (P <0 .0 5)。结论 :卡维地洛可能独立于降压外抑制NF κB的活化来调控MCP 1表达。