Molecular Signalling Pathways and Cellular Stress in Diabetic Embryopathy

糖尿病胚胎病的分子信号通路和细胞应激

• 批准号: 8767371
• 负责人: E. Albert Reece
• 金额: $ 42.92万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8767371
• 关键词: Acetylation; Age; American; Antioxidants; Apoptosis; Binding; Binding Proteins; Caring; Cell membrane; Cells; Cellular Stress; Child; Congenital Abnormality; CpG Islands; DNA; DNA Methyltransferase; DNA Modification Methylases; DNMT3a; Deacetylase; Diabetes Mellitus; Down-Regulation; Endoplasmic Reticulum; Enzymes; Event; Exhibits; Exposure to; Genetic Transcription; Health; Hyperglycemia; Hypermethylation; Knock-out; Knockout Mice; Mediating; Methylation; Mitochondria; Molecular; Mutation; Neural Tube Defects; Neural tube; Neuroepithelial Cells; Oxidative Stress; Pathway interactions; Phosphorylation; Phosphorylation Site; Post-Translational Protein Processing; Pregnancy in Diabetics; Protein Isoforms; Protein Kinase C; Proteins; Relative (related person); Risk Factors; Role; Signal Pathway; Structural Congenital Anomalies; Testing; Time; Transgenic Mice; Woman; Work; base; diabetic; diabetic embryopathy; endoplasmic reticulum stress; glycemic control; knowledge base; malformation; maternal diabetes; mitochondrial dysfunction; mutant; myristoylated alanine-rich C kinase substrate; non-diabetic; novel; overexpression; prevent; promoter; public health relevance; reproductive; restoration; success; transcription factor

DESCRIPTION (provided by applicant): Congenital malformations occur in up to 10% of babies born to diabetic women. Optimal glycemic control is difficult to achieve and maintain, and even transient exposure to hyperglycemia can cause malformations. This current proposal is formulated on the basis of our findings relative to the PKC pathway, which is critically involved i the induction of diabetic embryopathy. Because the molecular intermediates downstream PKC activation have not been determined, we have advanced a novel hypothesis that maternal hyperglycemia-induced PKCa/d activation reduces the expression of SIRT2 through DNA hypermethylation. SIRT2 downregulation prevents sustainable antioxidant enzyme expression and induces MARCKS hyperacetylation, which contributes to MARCKS phosphorylation. PKC-dependent SIRT2 downregulation and MARCKS phosphorylation in the developing neural tube are responsible for cellular stresses that cause neuroepithelial cell apoptosis and NTD formation. Aim 1 will determine whether PKCa and PKCd suppress SIRT2 expression through DNA hypermethylation in diabetic embryopathy. We hypothesize that that PKCa and PKCd increases the expression of de novo DNA methyltransferases (DNMT3A/B), which induce hypermethylation in the SIRT2 promoter and inhibit its expression. Aim 2 will determine the role of SIRT2 in PKC-induced cellular stress, MARCKS phosphorylation and NTD formation in diabetic embryopathy. Our working hypothesis is that downregulation of SIRT2 decreases antioxidant enzyme expression, which results in oxidative and endoplasmic reticulum stress, and leads to an increase in MARCKS acetylation and phosphorylation, which contributes to cellular stress. Aim 3 will determine the causal role of MARCKS phosphorylation in diabetes-induced cellular stress, apoptosis and NTD formation. We will test the hypothesis that PKCa/d-dependent MARCKS phosphorylation induces cellular stress and mitochondrial dysfunction, resulting in apoptosis and NTD formation. The success of this project will significantly fill the gaps in the current knowledge base regarding events that cause diabetic embryopathy.

描述（由申请人提供）：先天性畸形发生在高达10%的婴儿出生的糖尿病妇女。最佳血糖控制难以实现和维持，即使短暂暴露于高血糖也会导致畸形。目前的建议是制定的基础上，我们的研究结果相对于蛋白激酶C途径，这是至关重要的参与诱导糖尿病胚胎病。由于PKC激活下游的分子中间体尚未确定，我们提出了一个新的假设，即母体高血糖诱导的PKC/d激活通过DNA超甲基化减少SIRT 2的表达。SIRT 2下调会阻止抗氧化酶的可持续表达并诱导MARCKS过度乙酰化，从而促进MARCKS磷酸化。发育中的神经管中PKC依赖性SIRT 2下调和MARCKS磷酸化是导致神经上皮细胞凋亡和NTD形成的细胞应激的原因。目的1将确定是否PKCa和PKCd抑制SIRT 2的表达，通过DNA甲基化在糖尿病胚胎病变。我们假设PKCa和PKCd增加了从头DNA甲基转移酶（DNMT 3A/B）的表达，这诱导SIRT 2启动子的超甲基化并抑制其表达。目的2将确定SIRT 2在糖尿病胚胎病中PKC诱导的细胞应激、MARCKS磷酸化和NTD形成中的作用。我们的工作假设是SIRT 2的下调降低了抗氧化酶的表达，这导致氧化和内质网应激，并导致MARCKS乙酰化和磷酸化的增加，这有助于细胞应激。目的3将确定MARCKS磷酸化在糖尿病诱导的细胞应激、凋亡和NTD形成中的因果作用。我们将测试PKCa/d依赖性MARCKS磷酸化诱导细胞应激和线粒体功能障碍，导致细胞凋亡和NTD形成的假设。该项目的成功将显著填补目前关于导致糖尿病胚胎病事件的知识基础的空白。