关键词： brain ischemia   MCAO   ATF3   lentiviral overexpression   glutamate neurotoxicity   reporter assay  

摘要： This study evaluates the pathological role of the stress sensor activating transcription factor-3 (ATF3) in ischemic neurotoxicity. Upregulation of the transcript and protein for ATF3 was seen 2-10 hr after reperfusion in the ipsilateral cerebral hemisphere of mice with transient middle cerebral artery occlusion for 2 hr. Immunohistochemical analysis confirmed the expression of ATF3 by cells immunoreactive for a neuronal marker in neocortex, hippocampus, and striatum within 2 hr after reperfusion. In murine neocortical neurons previously cultured under ischemic conditions for 2 hr, transient upregulation of both Atf3 and ATF3 expression was similarly found during subsequent culture for 2-24 hr under normoxia. Lentiviral overexpression of ATF3 ameliorated the neurotoxicity of glutamate (Glu) in cultured murine neurons along with a slight but statistically significant inhibition of both Fluo-3 and rhodamine-2 fluorescence increases by N-methyl-D-aspartate. Similarly, transient upregulation was seen in Atf3 and ATF3 expression during the culture for 48 hr in neuronal Neuro2A cells previously cultured under ischemic conditions for 2 hr. Luciferase reporter analysis with ATF3 promoter together with immunoblotting revealed the possible involvement of several transcription factors responsive to extracellular and intracellular stressors in the transactivation of the Atf3 gene in Neuro2A cells. ATF3 could be upregulated to play a role in mechanisms underlying mitigation of the neurotoxicity mediated by the endogenous neurotoxin Glu at an early stage after ischemic signal inputs. (c) 2016 Wiley Periodicals, Inc.

关键词： STAPHYLOCOCCUS aureus   LISTERIA monocytogenes  

摘要： A correction to the article 'ATF3 provides protection from Staphylococcus aureus and Listeria monocytogenes infections' that was published in the April 19, 2016 issue is presented.

关键词： Transcription factors   B cells   Lymphomas   Genes   Immunoassay  

摘要： The article describes the expression pattern and the role of different members of the activating transcription factor (ATF) family in survival of diffuse large B-cell lymphoma (DLBCL) cell. The composition of AP-1 complexes determines the genes that are regulated, either positively or negatively. Immuno-histochemical analysis revealed strong nuclear ATF3 expression in tumors from ABC DLBCL patients.

关键词： Echinacoside   Parkinson＇s disease   1-Methyl-4-phenylpyridinium ion. Reactive oxygen species   ATF3   CHOP  

摘要： Echinacoside （ECH） is protective in a mouse model of Parkinson＇ s disease （PD） induced by 1-methyl-4- phenylpyridinium ion （MPP＋）. To investigate the mechanisms involved, SH-SYSY neuroblastoma ceils were treated with MPP＋ or a combination of MPP＋ and ECH, and the expression of ATF3 （activating transcription factor 3）, CHOP （C/EBP-homologous protein）, SCNA （synuclein alpha）, and GDNF （glial cell line-derived neurotrophic factor） was assessed. The results showed that ECH significantly improved cell survival by inhibiting the generation of MPP＋-induced reactive oxygen species （ROS）. In addition, ECH suppressed the ROS and MPP＋- induced expression of apoptotic genes （ATF3, CHOP, and SCNA）. ECH markedly decreased the MPP＋-induced cas- pase-3 activity in a dose-dependent manner. ATF3- knockdown also decreased the CHOP and cleaved caspase- 3 levels and inhibited the apoptosis induced by MPP＋. Interestingly, ECH partially restored the GDNF expression that was down-regulated by MPP＋. ECH also improved dopaminergic neuron survival during MPP＋ treatment and protected these neurons against the apoptosis induced by MPTP. Taken together, these data suggest that the ROS/ ATF3/CHOP pathway plays a critical role in mechanisms by which ECH protects against MPP＋-induced apoptosis in PD.

关键词： Activating transcription factor 3   Cardiac remodeling   Hypertrophy   Autophagy   Macrophages  

关键词： Bortezomib   CCL2   Allodynia   c-Jun   ATF3  

摘要： Bortezomib (BTZ) is a frequently used chemotherapeutic drug for the treatment of refractory multiple myeloma and hematological neoplasms. The mechanism by which the administration of BTZ leads to painful peripheral neuropathy remains unclear. In present study, we found that application of BTZ at 0.4 mg/kg for consecutive 5 days significantly increased the expression of CCL2 in DRG, and intrathecal administration of neutralizing antibody against CCL2 inhibited the mechanical allodynia induced by BTZ. We also found an increased expression of c-Jun in DRG, and that inhibition of c-Jun signaling prevented the CCL2 upregulation and mechanical allodynia in the rats treated with BTZ. Furthermore, the results with luciferase assay in vitro and ChIP assay in vivo showed that c-Jun might be essential for BTZ-induced CCL2 upregulation via binding directly to the specific position of the ccl2 promoter. In addition, the present results showed that an upregulated expression of ATF3 was co-expressed with c-Jun in the DRG neurons, and the enhanced interaction between c-Jun and ATF3 was observed in DRG in the rats treated with BTZ. Importantly, pretreatment with ATF3 siRNA significantly inhibited the recruitment of c-Jun to the ccl2 promoter in the rats treated with BTZ. Taken together, these findings suggested that upregulation of CCL2 resulting from the enhanced interaction between c-Jun and ATF3 in DRG contributed to BTZ-induced mechanical allodynia. (C) 2015 Published by Elsevier Inc.

关键词： Activating transcription factor 3   Endoplasmic reticulum stress   Reactive oxygen species   Liver cancer  

摘要： Background: Hepatocellular carcinoma (HCC) is one of most common and aggressive human malignancies in the world, especially, in eastern Asia, and its mortality is very high at any phase. We want to investigate mechanism of niclosamide inducing cell apoptosis in HCC. Methods: Two hepatoma cell lines were used to evaluate activity of niclosamide inducing cell apoptosis and study its mechanism. Quantitative real-time PCR and western blotting were used in analysis of genes expression or protein active regulated by niclosamide. Results: Niclosamide remarkably induced cell apoptosis in hepatoma cells. Furthermore, our study revealed that RNA-dependent protein kinase-like kinase (PERK) is activated and its expression is up-regulated in HCC cells which are exposed to niclosamide. niclosamide also significantly increase activating transcription factor 3 (ATF3), activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein-homologous protein (CHOP) expression in HCC cells. It's suggested that the function of niclosamide was abrogated by PERK inhibitor or absent ATF3. Expression of PERK and CHOP is correlated with ATF3 level in the cells. Conclusion: Taken together, our results indicate that ATF3 plays an integral role in ER stress activated and cell apoptosis induced by niclosamide in HCC cells. In this study, the new mechanism of niclosamide as anti-cancer we investigated, too.

关键词： ATF3   cleaved caspase 3   diabetes   nerve reconstruction   Schwann cell  

摘要： Knowledge about nerve regeneration after nerve injury and reconstruction in appropriate diabetic animal models is incomplete. Short-term nerve regeneration after reconstruction of a 10-mm sciatic nerve defect with either a hollow chitosan conduit or an autologous nerve graft was investigated in healthy Wistar and diabetic Goto-Kakizaki (GK) rats. After 21days, axonal outgrowth, the presence of activated and apoptotic Schwann cells and the thickness of the formed matrix in the conduits were measured. In general, nerve regeneration was superior in autologous nerve grafts. In chitosan conduits, a matrix, which was thicker in diabetic rats, was formed and was positively correlated with length of axonal outgrowth. Axonal outgrowth in conduits and in nerve grafts extended further in diabetic rats than in healthy rats. There was a higher percentage of activating transcription factor3 (ATF3)-immunostained cells in nerve segments from healthy rats than in diabetic rats after autologous nerve graft reconstruction. In chitosan conduits, more cleaved caspase 3-stained Schwann cells were generally observed in the matrix from the diabetic rats than in healthy rats. However, there were fewer apoptotic cells in the distal segment in diabetic rats reconstructed with a chitosan conduit. Preoperative glucose levels were positively correlated with axonal outgrowth after both reconstruction methods. Axonal regeneration was better in autologous nerve grafts than in hollow chitosan conduits and was enhanced in diabetic GK rats compared to healthy rats after reconstruction. This study provides insights into the nerve regeneration process in a clinically relevant diabetic animal model.

关键词： 炎症反应   重组高密度脂蛋白   载脂蛋白   突变体   活化转录因子3   基因表达  

摘要： 目的：ATF3在抑制炎症信号中通过抑制TLR的产生而发挥重要作用，高密度脂蛋白（HDL）或其主要蛋白成份 ApoA-I具有显著的抗炎症作用。本研究探讨载脂蛋白 A-Ⅰ（ApoA-Ⅰ）及其半胱氨酸突变体重组高密度脂蛋白对ATF3表达量的影响。\n 方法：⑴利用pET原核表达系统表达载脂蛋白A-Ⅰ74，A-Ⅰ228，A-Ⅰm和A-ⅠWT，亲和层析纯化后，加入DPPC，制作成重组高密度脂蛋白。⑵培养RAW264.7细胞，LPS刺激诱导炎症细胞模型，然后给于重组高密度脂蛋白干预，ELISA试剂盒检测炎症因子IL-6和TNF-α的表达水平，观察细胞形态学的改变，RT-PCR和western blotting检测细胞中转录激活因子ATF3mRNA和蛋白表达水平的变化。\n 结果：细胞形态学观察发现，与正常组比较，LPS组与 rHDL228组细胞形态趋向于巨噬细胞化并出现降解，rHDL74、rHDLM和rHDLWT对LPS刺激的细胞有不同的保护作用。ELISA检测发现，rHDL74、 rHDLm和rHDLwt中TNF-ɑ与IL-6的表达水平恢复到接近空白对照组水平，rHDL228组TNF-ɑ与IL-6水平较较空白对照组明显升高（p<0.01）。rHDL74、 rHDLM和rHDLWT中TNF-ɑ与IL-6水平较LPS组明显降低（P<0.01）。Western blotting结果显示,与对照组相比，LPS组与rHDL228组ATF3的表达水平下降，具有显著性差异（p<0.01）。rHDL74、rHDLM和rHDLWT组表达水平明显升高且差异显著(p<0.05)。\n 结论：重组高密度脂蛋白rHDL74、rHDLWT、rHDLM促进ATF3在mRNA和蛋白水平上的表达。而rHDL228下调其表达。

关键词： 内皮炎症   功能紊乱   内皮细胞   ATF3蛋白   转录激活因子3   SUMO化   血管紧张素Ⅱ  

摘要： 研究背景与目的:随着研究的深入，蛋白质翻译后修饰在心血管疾病中的作用也逐渐被揭示。SUMO化(small ubiquitin-related modification，SUMOylation)作为蛋白质翻译后修饰的一种，是类似于泛素化的一种酶级联反应，因此也称作类泛素化。它的基本过程是，SUMO小分子通过酶促反应共价结合到靶蛋白的赖氨酸位点上，进而调控靶蛋白的活性，功能，细胞定位等等。同时蛋白质的SUMO化也是一个可逆的过程。转录激活因子3(activating transcription factor3，ATF3)是一种适应性的转录因子，可以被许多外界刺激所诱导进而参与疾病的发生。内皮细胞作为血管的第一道屏障，在维持血管稳态中发挥关键性作用。现有的研究多聚焦在ATF3蛋白水平的变化影响了细胞的功能等等，但ATF3 SUMO化的功能研究还不明确。我们研究发现在血管活性物质AngiotensinⅡ(AngⅡ)的作用下，内皮细胞中的ATF3 SUMO化水平升高，而SUMO化这种蛋白质翻译后修饰是否在AngⅡ诱导的内皮炎症和内皮功能紊乱中发挥作用还不清楚。因此本研究的目的旨在:1、探讨ATF3 SUMO化在体内和体外内皮细胞中的发生。2、探讨ATF3SUMO化在内皮细胞中的作用。\n 研究方法与结果:体外培养的脐静脉内皮细胞系(HUVECs)，加入AngⅡ刺激后ATF3和SUMO1蛋白表达量升高。同时，我们通过免疫荧光和En face染色发现在AngⅡ诱导的高血压小鼠的胸主动脉的内皮细胞中，ATF3和SUMO1的表达量也升高了，而且共定位显示两者表达位置一致。进一步，我们通过HUVECs的免疫共沉淀(co-IP)实验发现，ATF3在AngⅡ的刺激下可以被SUMO1结合发生SUMO化，且发生的位点是ATF3的第42位赖氨酸。ATF3蛋白水平的升高不伴有mRNA水平的升高提示我们ATF3的SUMO化可能与ATF3的稳定性有关。因此我们检测了AngⅡ刺激的HUVECs中沉默SUMO1基因后ATF3的表达量，结果显示ATF3的表达不再被AngⅡ所调节。此外，泛素小分子ubiquitin和SUMO1同时过表达时，我们发现ATF3优先与SUMO1结合而逃避了泛素化降解这一过程。接着我们探索了ATF3 SUMO化在内皮炎症和内皮功能紊乱方面的作用。结果显示ATF3和其他的bZIP蛋白一起参与了内皮炎症的发生，并且ATF3SUMO化可以调控内皮一氧化氮的产生。在血管环实验中，SUMO化抑制剂银杏酸(GA)有效地改善了AngⅡ诱导的高血压小鼠主动脉的舒张功能。\n 研究结论:本研究发现AngⅡ可以在体内和体外的内皮细胞中上调ATF3 SUMO化水平。SUMO化增加了ATF3蛋白在体内的稳定性。SUMO化的ATF3的参与了内皮炎症和内皮功能紊乱的发生。