关键词： activating transcription factor 3   cartilage   chondrocytes   IL-1 beta   long non-coding RNA   osteoarthritis   RP11-364P22.2   LONG NONCODING RNAS   FACTOR-KAPPA-B   EXPRESSION PROFILE   OSTEOARTHRITIS   TRANSCRIPTION   LOCALIZATION   INTERLEUKIN-1-BETA   MECHANISMS  

摘要： Osteoarthritis (OA) is a degenerative joint disease which lacks effective medical treatment due to ill-defined molecular mechanisms underlying the pathology. Inflammation is a key factor that induces and aggravates OA. Therefore, the current study aims to explore roles of the dysregulated long non-coding RNAs in the pro-inflammatory cytokine IL-1 beta-mediated catabolic effects in cartilage tissue and chondrocytes. We identified RP11-364P22.2 as dysregulated in OA patient-derived cartilage tissues and highly responsive to IL-1 beta stimulus. RNA pull-down coupled with mass spectrometry demonstrated that RP11-364P22.2 physically binds to activating transcription factor 3 (ATF3) and thus increases the protein stability and facilitates its nuclear translocation. Loss- and gain-of-function assays indicated that the interaction between RP11-364P22.2 and ATF3 is indispensable for the detrimental effects of IL-1 beta including growth inhibition, apoptosis induction as well as degradation of the key chondrocyte structural proteins of type II collage and Aggrecan and synthesis of the extracellular matrix-degrading enzyme MMP13 in chondrocytes. In vivo, depletion of the RP11-364P22.2 effector ATF3 drastically prevented OA development in the rats with surgical destabilization of the medial meniscus (DMM). These results highlight the important roles of lncRNAs in the pathogenesis of OA and indicate the RP11-364P22.2/ATF3 regulatory axis as a potential therapeutic target of inflammation-induced OA.

关键词： apoptosis   ATF3   C   EBP homologous protein   hematopoietic stem cell function   ROS   STRESS   HOMEOSTASIS   NICHE  

摘要： Hematopoietic stem cells (HSCs) reside in a quiescent niche to reserve their capacity of self-renewal. Upon hematopoietic injuries, HSCs enter the cell cycle and encounter protein homeostasis problems caused by accumulation of misfolded proteins. However, the mechanism by which protein homeostasis influences HSC function and maintenance remains poorly understood. Here, we show that C/EBP homologous protein (CHOP), demonstrated previously to induces cell death upon unfolded protein response (UPR), plays an important role in HSCs regeneration. CHOP-/- mice showed normal hematopoietic stem and progenitor cell frequencies in steady state. However, when treated with 5-FU, CHOP deficiency resulted in higher survival rates, associated with an increased number of HSCs and reduced level of apoptosis. In serial competitive transplantation experiments, CHOP-/- HSCs showed a dramatic enhancement of repopulation ability and a reduction of protein aggresomes. Mechanistically, CHOP deletion causes reduced ATF3 expression and further leads to decreased protein aggregation and ROS. In addition, CHOP-/- HSCs exhibited an increased resistance to IR-induced DNA damage and improved HSCs homeostasis and function in telomere dysfunctional (G3Terc(-/-)) mice. In summary, these findings disclose a new role of CHOP in the regulation of the HSCs function and homeostasis through reducing ATF3 and ROS signaling.

关键词： HGF   c-met   Sensory neuron   Neurite outgrowth   Axon regeneration   Peripheral neuropathy   C-JUN   MAP KINASE   REGENERATION   MET   ACTIVATION   UROKINASE   TRANSPORT   CALCIUM   ATF3  

摘要： Hepatocyte growth factor (HGF) is a neurotrophic factor and its role in peripheral nerves has been relatively unknown. In this study, biological functions of HGF and its receptor c-met have been investigated in the context of regeneration of damaged peripheral nerves. Axotomy of the peripheral branch of sensory neurons from embryonic dorsal root ganglia (DRG) resulted in the increased protein levels of HGF and phosphorylated c-met. When the neuronal cultures were treated with a pharmacological inhibitor of c-met, PHA665752, the length of axotomy-induced outgrowth of neurite was significantly reduced. On the other hand, the addition of recombinant HGF proteins to the neuronal culture facilitated axon outgrowth. In the nerve crush mouse model, the protein level of HGF was increased around the injury site by almost 5.5-fold at 24 h post injury compared to control mice and was maintained at elevated levels for another 6 days. The amount of phosphorylated c-met receptor in sciatic nerve was also observed to be higher than control mice. When PHA665752 was locally applied to the injury site of sciatic nerve, axon outgrowth and injury mediated induction of cJun protein were effectively inhibited, indicating the functional involvement of HGF/c-met pathway in the nerve regeneration process. When extra HGF was exogenously provided by intramuscular injection of plasmid DNA expressing HGF, axon outgrowth from damaged sciatic nerve and cJun expression level were enhanced. Taken together, these results suggested that HGF/c-met pathway plays important roles in axon outgrowth by directly interacting with sensory neurons and thus HGF might be a useful tool for developing therapeutics for peripheral neuropathy.

关键词： Taxus chinensis var   mairei   NCI-1975 cells   Apoptosis   ATF3   Hippo-YAP pathway   DNA-DAMAGE   TUMORIGENESIS   INDUCTION   PROGRESSION  

摘要： Taxus chinensis var. mairei (TC) is a traditional Chinese ornamental and medicinal plant, the leaves and twigs of which are used in anti-tumor therapy in southern China. However, the mechanism and role of aqueous extract of TC (AETC) in promoting apoptosis in non-small cell lung cancer (NSCLC) cell lines has remained unclear. In this research, we observed that AETC inhibited the suppression of the proliferation of NSCLC cells and highly inhibited the proliferation of NCI-1975 cells. Furthermore, AETC exerted minimal inhibitory effects on normal human lung epithelial cells and induced apoptosis in NCI-1975 and A549 cells. The findings of RNA sequencing, qRT-PCR, western blotting, and immunofluorescence showed that upregulated ATF3 expression and ATF3 gene knockdown, respectively, increased and decreased the anti-tumor effects of AETC associated with Hippo pathway inhibition and decreased YAP degradation. Furthermore, AETC reduced the tumor volume and weight in nude mice; upregulated ATF3, p-MOB1, and p-YAP (Ser397); and actively regulated cleaved PARP and cleaved caspase-9/8/3. These findings suggest that AETC induced NSCLC cell apoptosis via the ATF3-Hippo-YAP pathway in vivo and in vitro. We also found that AETC is non-toxic to normal cells and nude mice. Thus, AETC might represent a promising adjuvant for anti-tumor therapy against NSCLC.

关键词： Macrophage senescence   Pseudomonas aeruginosa   ATF3   ROS   Inflammation  

摘要： Pseudomonas aeruginosa (PA) is one of the most prevalent pathogens that cause nosocomial infection in critical patients. Previously, we reported PA induced macrophage to senescence under the circumstance of infection. As an oxidative stress responsiveness element, activating transcription factor 3 (ATF3) might be involved in the macrophage senescence process. To test this presumption, we manipulated the expression of ATF3 in macrophage by using a PAO1 infection system. In the present study, ATF3 expression in macrophage was increased, following the duration and colony counts of PAO1 infection. Knockdown of ATF3 in macrophage resulted in increased percentage of senescent macrophage under PAO1 infection, while overexpressing ATF3 partly blocked PAO1-induced macrophage senescence. In accordance with the senescent phenotype, elevated reactive oxygen species (ROS) production was shown in ATF3 knockdown macrophages. Also, capacity of phagocytosis was also affected by manipulation of ATF3 expression in macrophages, and increased phagocytosed fluorescent beads was found in ATF3 knockdown macrophage. ATF3 might regulate the senescence process through influence on NF-kappa B translocation. During infection, the overexpression or downregulation of ATF3 in macrophage negatively modulated the translocation of NF-kappa B p65 and its phosphorylation at Ser-536. As a result, IL-6 and TNF alpha was elevated, while IL-10 decreased in case of ATF3 knockdown. In conclusion, ATF3 negatively regulates NF-kappa B translocation and activation, and participates in PA-induced macrophage senescence. As oxidative stress and inflammation induced element, ATF3 may modulate macrophage-related host defense.

摘要： Decidualization is a complex process involving cellular proliferation and differentiation of the endometrial stroma and is required to establish and support pregnancy. Dysregulated decidualization has been reported to be a critical cause of recurrent implantation failure (RIF). In this study, we found that Activating transcription factor 3 (ATF3) expression was significantly downregulated in the endometrium of RIF patients. Knockdown of ATF3 in human endometrium stromal cells (hESCs) hampers decidualization, while overexpression could trigger the expression of decidual marker genes, and ameliorate the decidualization of hESCs from RIF patients. Mechanistically, ATF3 promotes decidualization by upregulating FOXO1 via suppressing miR-135b expression. In addition, the endometrium of RIF patients was hyperproliferative, while overexpression of ATF3 inhibited the proliferation of hESCs through CDKN1A. These data demonstrate the critical roles of endometrial ATF3 in regulating decidualization and proliferation, and dysregulation of ATF3 in the endometrium may be a novel cause of RIF and therefore represent a potential therapeutic target for RIF.

关键词： Mesenchymal stem cells-derived extracellular vesicles   microRNA-222   ATF3   AKT1   Colorectal cancer   METASTASIS   BIOMARKERS   MIR-222-3P   ACTIVATION   MIGRATION   INVASION  

摘要： BackgroundImmunotherapy has been recently established as a new direction for the treatment of colorectal cancer (CRC), a gastrointestinal cancer. In this investigation, we aimed to expound how the posttranscriptional regulation modulated by microRNA-222 (miR-222) from mesenchymal stem cells-derived extracellular vesicles (MSC-EVs) affected the AKT pathway and the immune escape in *** cell malignant phenotype, including proliferation, migration, invasion, and apoptosis, was firstly detected after co-culture with MSC-EVs. miRNAs with differential changes in CRC cells before and after EVs treatment were filtered by microarray analysis. miR-222 was then downregulated to examine its role in CRC cells in response to EVs. Cells were implanted in mice to induce xenograft tumors, and infiltrating T cells was assessed by immunohistochemistry. The mRNA microarray was used to screen target genes, followed by rescue experiments. ChIP and western blot were conducted to validate the downstream biomolecule of *** treatment of CRC cells with MSC-EVs, the expression of miR-222 was upregulated, and cell activity was increased. Inhibition of miR-222 decreased CRC malignant aggressiveness in vitro and reduced tumorigenesis and immune escape in vivo. miR-222 targeted and bound to ATF3. Downregulation of ATF3 enhanced CRC cell malignant aggressiveness, tumorigenic capacity and immune escape. Mechanistically, ATF3 inhibited AKT1 transcription and mediated the AKT ***-EVs carry miR-222 to promote CRC cell malignant aggressiveness and immune escape. miR-222 targets and binds to ATF3, which inhibits AKT1 transcriptional activity and thereby mediates the AKT pathway.

关键词： 急性肾损伤   早期诊断   体外循环   ATF3   Kim-1  

摘要： 目的:探讨尿转录活化因子3(activating transcription factor 3,ATF3)和肾损伤因子1(kidney injury molecule 1,Kim-1)对体外循环(cardiopulmonary bypass,CPB)心脏手术后急性肾损伤(acute kidney injury,AKI)早期诊断的价值。方法:选取2018年1月—2019年12月于上海市第十人民医院心脏外科行体外循环心脏手术的患者83例,根据改善全球肾脏疾病预后组织诊断标准分为AKI组和非AKI组。收集患者术前及术后2 h、6 h、12 h、24 h、48 h尿液样本,采用酶联免疫吸附试验检测各时间点尿ATF3和Kim-1的水平,并计算尿[ATF3]·[Kim-1]的值。通过绘制受试者工作特征(ROC)曲线计算曲线下面积(AUC),评估尿ATF3、Kim-1以及[ATF3]·[Kim-1]早期诊断AKI的临床价值。结果:共42例患者发生AKI。与非AKI组相比,AKI组患者术后6 h、12 h尿ATF3明显升高,且术后12 h尿ATF3水平诊断AKI的AUC为0.691(95%CI:0.576~0.807),截断值为1216 pg/mL时,灵敏度为0.43,特异度为0.85。尿[ATF3]·[Kim-1]联合检测的AUC在术后6 h为0.712,达到最高值,灵敏度和特异度分别为0.57和0.78。结论:尿ATF3在体外循环心脏术后患者的尿液中早期表达,可以作为成人体外循环术后AKI的诊断标志物。联合使用的预测价值高于单个检测,是增加诊断准确度的可行办法。

关键词： 绵羊   ATF3基因   生物信息学分析   营养应激   调控元件  

摘要： 本研究旨在探究绵羊ATF3基因的蛋白特征、转录调控元件及其在营养剥夺应激下的表达变化。运用生物信息学相关软件对绵羊ATF3蛋白特征和ATF3基因启动子区元件进行分析预测,并在绵羊禁食3 d后检测骨骼肌中ATF3mRNA的表达量。结果显示,绵羊ATF3氨基酸数为187,分子式为C920H1521N273O282S12,等电点为8.89,不稳定系数是71.73,总平均疏水性值为-0.630;ATF3蛋白定位于细胞核,二级结构主要由α螺旋和无规则卷曲组成,三级结构与二级结构保持一致且可信度高;进化树显示绵羊ATF3与牛、山羊、猪的同源性较高;qRT-PCR结果显示,与正常组相比,禁食组绵羊骨骼肌中ATF3mRNA表达量极显著降低;绵羊ATF3基因启动子区存在CREB、NFKB、AP1和GRE等与应激有关的转录因子结合元件,暗示了ATF3表达量下调的原因可能与这些元件和相应转录因子的结合有关。

关键词： arsenic   ATF3   Bcl-xL   DR5   apoptosis  

摘要： Arsenic is one of the most common environmental pollutants eliciting serious public health issues; however, it is also a well-recognized chemotherapeutic agent for acute promyelocytic leukemia. The association between arsenic exposure and lung diseases has been established, but underlying molecular mechanisms are poorly defined. Here we investigated the toxicology of arsenic in airway epithelium. Arsenic rapidly induced the activating transcription factor ATF3 expression through the JNK and p38 pathways. The ATF3-deficient BEAS-2B cells were relatively resistant to apoptosis upon arsenic exposure, indicating a facilitatory role of ATF3 in arsenic-induced apoptosis. We further showed that ATF3 oppositely regulated the transcription of death receptor (DR5) and Bcl2-like 1 (Bcl-xL) by directly binding to the promoter DR5 and Bcl-xL. Altogether, our findings establish ATF3 as a pro-apoptotic protein in arsenic-induced airway epithelial apoptosis through transcriptionally regulating DR5 and Bcl-xL, highlighting the potential of ATF3 as an early and sensitive biomarker for arsenic-caused lung injury.