目的:探讨IRX1甲基化在心力衰竭(HF)大鼠中的作用机制。方法:通过生物信息学分析选择HF大鼠心肌细胞中的靶基因;通过TAC手术构建HF实验大鼠模型,并分组为假手术组(Sham组)、TAC组、Sham+5-Aza组和TAC+5-Aza组。通过心脏超声检测大鼠心...目的:探讨IRX1甲基化在心力衰竭(HF)大鼠中的作用机制。方法:通过生物信息学分析选择HF大鼠心肌细胞中的靶基因;通过TAC手术构建HF实验大鼠模型,并分组为假手术组(Sham组)、TAC组、Sham+5-Aza组和TAC+5-Aza组。通过心脏超声检测大鼠心脏功能,免疫组织化学染色评价心脏损伤程度;GSEA分析功能基因的相对丰富度。通过免疫荧光分析、Western blotting和qRT-PCR检测DNA甲基化和表达水平。结果:与正常人的基因组相比,HF患者基因组中甲基化程度显著提高,生物信息学分析确定IRX1为靶基因,IRX1表达与CXCL14/NF-κB之间存在显著相关性。超声心动图评估HF大鼠心脏功能的结果显示,与TAC组相比,TAC+5-Aza组的左心室与体重的比率显著降低,而LVDP、dP/dtmax和EF显著增加(P<0.01)。免疫染色结果显示,与TAC组相比,TAC+5-Aza组心肌细胞排列紊乱的情况得到有效缓解并恢复正常心肌细胞状态。qRT-PCR及Western blotting结果显示,与TAC组相比,TAC+5-Aza组大鼠的基因组DNA甲基化、IRX1甲基化、左心室ANP、BNP基因和β-MHC m RNA的表达水平显著降低(P<0.01),α-MHC m RNA的表达水平、IRX1和CXCL14的m RNA和蛋白表达水平以及MMP9和C-FLIP蛋白表达水平显著增加(P<0.01)。心肌纤维化和心肌细胞凋亡实验结果显示,与TAC组相比,TAC+5-Aza组大鼠心肌纤维化和心肌细胞凋亡阳性率显著降低(P<0.01)。结论:HF模型大鼠的IRXI甲基化水平提高可能激活CXCL14/NF-κB表达,以改善TAC诱导的心肌纤维化和细胞凋亡情况。展开更多
Coronaviruses(CoVs)are a group of related enveloped RNA viruses that have severe consequences in a wide variety of animals by causing respiratory,enteric or systemic diseases.Porcine epidemic diarrhea virus(PEDV)is an...Coronaviruses(CoVs)are a group of related enveloped RNA viruses that have severe consequences in a wide variety of animals by causing respiratory,enteric or systemic diseases.Porcine epidemic diarrhea virus(PEDV)is an economically important CoV distributed worldwide that causes diarrhea in pigs.nsp14 is a nonstructural protein of PEDV that is involved in regulation of innate immunity and viral replication.However,the function and mechanism by which nsp14 modulates and manipulates host immune responses remain largely unknown.Here,we report that PEDV nsp14 is an NF-κB pathway antagonist.Overexpression PEDV nsp14 protein remarkably decreases SeV-,poly(I:C)-and TNF-α-induced NF-κB activation.Meanwhile,expression of proinflammatory cytokines is suppressed by nspl4.nsp14 inhibits the phosphorylation of IKKs by interacting with IKKs and p65.Furthermore,nsp14 suppresses TNF-α-induced phosphorylation and nuclear import of p65.Overexpression nsp14 considerably increases PEDV replication.These results suggest a novel mechanism employed by PEDV to suppress the host antiviral response,providing insights that can guide the development of antivirals against CoVs.展开更多
The role of the transcription factor NF-κB in shaping the cancer microenvironment is becoming increasingly clear. Inflammation alters the activity of enzymes that modulate NF-κB function, and causes extensive change...The role of the transcription factor NF-κB in shaping the cancer microenvironment is becoming increasingly clear. Inflammation alters the activity of enzymes that modulate NF-κB function, and causes extensive changes in genomic chromatin that ultimately drastically alter cell-specific gene expression. NF-κB regulates the expression of cytokines and adhesion factors that control interactions among adjacent cells. As such, NF-κB fine tunes tissue cellular composition, as well as tissues' interactions with the immune system. Therefore, NF-κB changes the cell response to hormones and to contact with neighboring cells. Activating NF-κB confers transcriptional and phenotypic plasticity to a cell and thereby enables profound local changes in tissue function and composition. Research suggests that the regulation of NF-κB target genes is specifically altered in cancer. Such alterations occur not only due to mutations of NF-κB regulatory proteins, but also because of changes in the activity of specific proteostatic modules and metabolic pathways. This article describes the molecular mode of NF-κB regulation with a few characteristic examples of target genes.展开更多
文摘目的:探讨IRX1甲基化在心力衰竭(HF)大鼠中的作用机制。方法:通过生物信息学分析选择HF大鼠心肌细胞中的靶基因;通过TAC手术构建HF实验大鼠模型,并分组为假手术组(Sham组)、TAC组、Sham+5-Aza组和TAC+5-Aza组。通过心脏超声检测大鼠心脏功能,免疫组织化学染色评价心脏损伤程度;GSEA分析功能基因的相对丰富度。通过免疫荧光分析、Western blotting和qRT-PCR检测DNA甲基化和表达水平。结果:与正常人的基因组相比,HF患者基因组中甲基化程度显著提高,生物信息学分析确定IRX1为靶基因,IRX1表达与CXCL14/NF-κB之间存在显著相关性。超声心动图评估HF大鼠心脏功能的结果显示,与TAC组相比,TAC+5-Aza组的左心室与体重的比率显著降低,而LVDP、dP/dtmax和EF显著增加(P<0.01)。免疫染色结果显示,与TAC组相比,TAC+5-Aza组心肌细胞排列紊乱的情况得到有效缓解并恢复正常心肌细胞状态。qRT-PCR及Western blotting结果显示,与TAC组相比,TAC+5-Aza组大鼠的基因组DNA甲基化、IRX1甲基化、左心室ANP、BNP基因和β-MHC m RNA的表达水平显著降低(P<0.01),α-MHC m RNA的表达水平、IRX1和CXCL14的m RNA和蛋白表达水平以及MMP9和C-FLIP蛋白表达水平显著增加(P<0.01)。心肌纤维化和心肌细胞凋亡实验结果显示,与TAC组相比,TAC+5-Aza组大鼠心肌纤维化和心肌细胞凋亡阳性率显著降低(P<0.01)。结论:HF模型大鼠的IRXI甲基化水平提高可能激活CXCL14/NF-κB表达,以改善TAC诱导的心肌纤维化和细胞凋亡情况。
基金This work was supported by grants from the National Key R&D Program of China(2018YFD0500103 and 2017YFD0501100)the Chinese Academy of Agricultural Science and Technology Innovation Project(CAAS-ASTIP-2021-LVRI and Y2017JC55)Central Public-interest Scientific Institution Basal Research Fund(1610312016013 and 1610312017003).
文摘Coronaviruses(CoVs)are a group of related enveloped RNA viruses that have severe consequences in a wide variety of animals by causing respiratory,enteric or systemic diseases.Porcine epidemic diarrhea virus(PEDV)is an economically important CoV distributed worldwide that causes diarrhea in pigs.nsp14 is a nonstructural protein of PEDV that is involved in regulation of innate immunity and viral replication.However,the function and mechanism by which nsp14 modulates and manipulates host immune responses remain largely unknown.Here,we report that PEDV nsp14 is an NF-κB pathway antagonist.Overexpression PEDV nsp14 protein remarkably decreases SeV-,poly(I:C)-and TNF-α-induced NF-κB activation.Meanwhile,expression of proinflammatory cytokines is suppressed by nspl4.nsp14 inhibits the phosphorylation of IKKs by interacting with IKKs and p65.Furthermore,nsp14 suppresses TNF-α-induced phosphorylation and nuclear import of p65.Overexpression nsp14 considerably increases PEDV replication.These results suggest a novel mechanism employed by PEDV to suppress the host antiviral response,providing insights that can guide the development of antivirals against CoVs.
文摘The role of the transcription factor NF-κB in shaping the cancer microenvironment is becoming increasingly clear. Inflammation alters the activity of enzymes that modulate NF-κB function, and causes extensive changes in genomic chromatin that ultimately drastically alter cell-specific gene expression. NF-κB regulates the expression of cytokines and adhesion factors that control interactions among adjacent cells. As such, NF-κB fine tunes tissue cellular composition, as well as tissues' interactions with the immune system. Therefore, NF-κB changes the cell response to hormones and to contact with neighboring cells. Activating NF-κB confers transcriptional and phenotypic plasticity to a cell and thereby enables profound local changes in tissue function and composition. Research suggests that the regulation of NF-κB target genes is specifically altered in cancer. Such alterations occur not only due to mutations of NF-κB regulatory proteins, but also because of changes in the activity of specific proteostatic modules and metabolic pathways. This article describes the molecular mode of NF-κB regulation with a few characteristic examples of target genes.
