Inflammatory Gene Regulation in Diabetic Conditions

描述（由申请人提供）：糖尿病、胰岛素抵抗和代谢综合征与心血管疾病的发生率显著加快相关。由炎性细胞因子和趋化因子触发的循环单核细胞的异常激活与这种病理学有关，但其潜在的分子机制尚未完全了解。在上一个资助期，我们提供了第一个证据，即体外和体内糖尿病条件通过新的核染色质重塑和潜在的表观遗传机制（涉及转录因子、共激活因子和染色质组蛋白乙酰化之间的协同作用）导致单核细胞中的炎症基因转录。我们评估了体外培养的单核细胞与糖尿病刺激，如高葡萄糖（HG）和配体的晚期糖基化终产物（AGEs），以及单核细胞从糖尿病患者。我们已经取得了很好的进展，完成了我们最初的大部分具体目标，并启动了几项新的研究。这个快速移动和动态的领域已经开辟了几条新的途径，将在这次更新中进行调查。我们已经发现了令人兴奋的新机制，炎症基因表达的单核细胞在糖尿病条件下，包括新的染色质因子的参与，和关键的microRNA（miR）的目标调节染色质重塑以及mRNA的稳定性。因此，目前的更新将把我们的研究带到一个新的开创性水平，并通过解开迄今为止尚未探索的糖尿病体内和体外单核细胞功能障碍相关基因调控机制来推进该领域。假设糖尿病状况通过涉及染色质组蛋白修饰和miR的转录机制以及涉及mRNA稳定的转录后机制导致单核细胞/巨噬细胞中炎性基因的表达增加。这将根据已发表的广泛的新的初步数据，通过4个特定目标进行评估。目的1和2将确定在体外培养的单核细胞中和在体内来自糖尿病受试者的单核细胞中的糖尿病状况如何通过这些基因启动子处的染色质的新变化导致炎性基因的转录。目的3将测试两个关键的新的micro-RNA（miR）的功能作用，在糖尿病单核细胞/巨噬细胞的差异调节。目的4将研究新的转录后机制，糖尿病刺激通过RNA结合蛋白和miR之间的新型相互作用增加关键炎症基因mRNA的稳定性。我们对转录组、表观基因组、核糖基因组和炎性小体之间的串扰的最先进和创新的评估可以为糖尿病和胰岛素抵抗条件下介导单核细胞功能障碍的细胞事件提供新的见解。这些已完成的研究可以大大提高我们对糖尿病血管疾病的认识，并为糖尿病的衰弱性血管并发症发现新的治疗靶点。

DESCRIPTION (provided by applicant): Diabetes, insulin resistance and the metabolic syndrome are associated with significantly accelerated rates of cardiovascular disease. Abnormal activation of circulating monocytes triggered by inflammatory cytokines and chemokines has been implicated in this pathology but the underlying molecular mechanisms are not fully understood. In the previous funding period, we provided the first evidence that diabetic conditions in vitro and in vivo lead to inflammatory gene transcription in monocytes via novel nuclear chromatin remodeling and potential epigenetic mechanisms involving co-operative effects between transcription factors, coactivators and chromatin histone acetylation. We evaluated monocytes cultured in vitro with diabetic stimuli such as high glucose (HG) and ligands of advanced glycation end products (AGEs), as well as monocytes from diabetic patients. We have made excellent progress and completed most of our original Specific Aims and also initiated several new studies. This rapidly moving and dynamic field has opened several new avenues that will be investigated in this renewal. We have uncovered exciting new mechanisms of inflammatory gene expression in monocytes under diabetic conditions including the involvement of novel chromatin factors, and key microRNAs (mIRs) whose targets modulate chromatin remodeling as well as mRNA stability. The current renewal will thus take our studies to a new pioneering level and advance the field by unraveling hitherto unexplored mechanisms of regulation of genes associated with monocyte dysfunction in vitro and in vivo in diabetes. The hypothesis is that diabetic conditions lead to increased expression of inflammatory genes in monocyte /macrophages via transcriptional mechanisms involving chromatin histone modifications and miRs, as well as post-transcriptional mechanisms involving mRNA stabilization. This will be evaluated by 4 Specific Aims based on published and extensive new preliminary data. Aims 1 and 2 will determine how diabetic conditions in vitro in cultured monocytes and in vivo in monocytes from diabetic subjects lead to the transcription of inflammatory genes via novel changes in the chromatin at these gene promoters. Aim 3 will test the functional roles of two key new micro-RNAs (miRs) that are differentially regulated in diabetic monocytes /macrophages. Aim 4 will examine new post-transcriptional mechanisms by which diabetic stimuli increase the stability of key inflammatory gene mRNAs via novel interplay between RNA binding proteins and miRs. Our state-of-the-art and innovative assessments of the cross-talk between the transcriptome, epigenome, ribo-gnome and the inflammasome can provide new insights into cellular events mediating monocyte dysfunction under diabetic and insulin resistant conditions. These completed studies can greatly advance our knowledge of diabetic vascular disease and uncover new therapeutic targets for the debilitating vascular complications of diabetes.