MAOA/H202 regulation by Dexamethasone & other Steroids in muscle and brain cells

地塞米松对 MAOA/H202 的调节

• 批准号: 7592499
• 负责人: Marc Roy Blackman
• 金额: $ 17.9万
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7592499
• 关键词: Acute; Adrenal Glands; Affect; Aftercare; Aging; Aldehydes; Amines; Apoptosis; Astrocytes; Atrophic; Behavior; Cardiomyopathies; Cardiovascular Diseases; Catecholamines; Cell Adhesion; Cells; Cellular Stress Response; Chronic; Chronic stress; Citric Acid Cycle; Condition; Databases; Deamination; Development; Dexamethasone; Diabetes Mellitus; Disease; Dopamine; Down-Regulation; Enzymes; Estrogens; Exposure to; Functional disorder; Gatekeeping; Gene Expression; Gene Expression Profile; Genes; Genetic; Genetic Polymorphism; Genetic Transcription; Genomics; Glucocorticoids; Glycolysis; Health; Heat-Shock Response; Homeostasis; Housing; Human; Hydrogen Peroxide; Inflammatory; Intervention; Label; Link; Malignant Neoplasms; Mediator of activation protein; Mental Depression; Mental disorders; Metabolic Pathway; Metabolic syndrome; Metabolism; Methaqualone; Mitochondria; Mitochondrial Proteins; Modality; Molecular Profiling; Monoamine Oxidase A; Monoamine Oxidase B; Monoamine Oxidase Inhibitors; Muscle; Muscle Cells; Muscle Fibers; Myopathy; Nerve Degeneration; Neurons; Nuclear; Obesity; Oxidative Phosphorylation; Pathogenesis; Pathology; Pathway interactions; Patients; Pharmacogenomics; Physiology; Play; Process; Production; Progesterone; Protein Biosynthesis; Proteins; Public Health; Publications; Publishing; RNA; Reactive Oxygen Species; Regulation; Reporting; Role; Serotonin; Skeletal Muscle; Skeletal system; Slide; Statistically Significant; Steroids; Stress; Testing; Therapeutic Agents; Therapeutic Intervention; Time; Tissues; Tyramine; Up-Regulation; Work; Xenobiotics; brain cell; cDNA Arrays; day; dehydroepiandrosterone; fetal; hormone regulation; human SLPI protein; lipid biosynthesis; lipid metabolism; male; mitochondrial dysfunction; novel; nucleotide metabolism; research study; tetrahydrodeoxycorticosterone; therapeutic target; time interval; tool; trend

No new work had been done on this project. Two publications have been published since last report and are listed below. Chronic stress is implicated in the pathogenesis of cardiovascular disease, the metabolic syndrome, neurodegeneration, depression and other psychiatric disorders, and inflammatory diseases. Skeletal myopathy and neuronal cell atrophy are common complications of endogenous and exogenous glucocorticoid excess; yet the underlying mechanisms remain unclear and targeted therapeutic interventions are limited. Mitochondria play a pivotal role in cell homeostasis, housing multiple metabolic pathways that result in energy production in the form of ATP. They also generate most cellular reactive oxygen species (ROS) and regulate programmed cell death, serving as a gatekeeper for apoptosis. Not surprisingly, primary or secondary mitochondrial dysfunction have been associated with the pathogenesis of conditions such as obesity, diabetes, cancer, neurodegeneration, cardiomyopathy, depression and aging, of obvious public health significance. Patients with the aforementioned diseases commonly use wide CAM modalities. To systematically study the contribution of mitochondrial genomics to human physiology and pathophysiology, we built a mitochondria-focused gene database and used it as reference for the development of a customized cDNA microarray (hMitChip), containing 501 mitochondria-related nuclear genes. To validate the ability of this mitochondrial microarray to detect changes in gene expression, we explored the pharmacogenomic effects of dexamethasone (Dex), a synthetic glucocorticoid, on the mitochondrial nuclear transcriptome in human skeletal muscle cells. Of the 501 mitochondria related genes arrayed in hMitChip, 23 (4.5%) displayed significant transcriptional changes in skeletal myocytes after treatment with Dex. Upregulation of genes involved in amine metabolism (MAOA and SAT) was statistically significant at all time intervals tested, whereas for genes involved in protein processing (AKAP10), oxidative phosphorylation (FDX1, CYBA), heat shock cellular stress response (HSPD1), lipid biosynthesis (FACL2), glycolysis (GCK) and mitochondrial protein synthesis (TSFM) upregulation was stastistically significant only at certain time points. Treatment for 7 days downregulated genes related to lipid metabolism (ACADVL, ACADM), the tricarboxylic acid cycle (DLST), protein processing (MPI, PPIB) and gene transcription (GABPA), whereas it induced genes involved in apoptosis (BNIP3). The CTNNA1 and AK1 genes, involved in cell adhesion and nucleotide metabolism, respectively, were also significantly downregulated after 7 days of exposure to 10-6 M of Dex. Reproducible results were obtained across multiple replicate experiments, and after reverse labeling of the hybridized slides For selected genes, the transcriptional changes detected with hMitChip were confirmed by QRT-PCR, carried out on RNA from the corresponding microarray experiments, as well as from separate time-course experiments, in which myocytes obtained from two independent healthy male donors were exposed to 10-6 M of Dex for up to 9 days. A significant induction of the MAOA gene was observed at every time point. Fold change increased over time, with a peak induction of 21.212.7 vs. untreated cells at day 5. FDX1 expression differed between Dex-treated and control cells at days 3 and 5, whereas FACL2 expression was different on days 5, 7, and 9, but with no significant increase over time. A trend towards downregulation was observed for ACADVL and ACADM after 7 days of exposure to Dex, consistent with the microarray findings, but failed to reach statistical significance. QRT-PCR results for selected genes, which were not differentially expressed in microarray experiments (i.e., NNT1, TOMM70) and were therefore used as negative controls, were also consistent with the microarray findings. We reported that the catecholamine-metabolizing enzyme MAO-A is a major target for glucocorticoids in human skeletal muscle cells.MAO catalyzes the oxidative deamination of neuroactive, vasoactive (serotonin, dopamine, catecholamines), or dietary (tyramine) amines and xenobiotics, releasing reactive aldehydes and H202. MAO-A activation by glucocorticoids with subsequent excess hydrogen peroxide production could represent a novel pathway for glucocorticoid-induced oxidative tissue damage, and MAO-inhibitors or other allopathic and CAM interventions aimed at different components of that pathway may serve as therapeutic agents. Genetic studies have linked MAO-A and MAO-B to various aspects of human behavior, and environmental interactions modulate the expression of certain MAO-A polymorphisms; however, the hormonal regulation of their expression in humans remains unexplored. We have begun to examine the effects of adrenal, gonadal and neurosteroids, in addition to glucocorticoids, on MAO expression in human fetal astrocytes. We hypothesized that estrogen, progesterone, DHEA and/or other neurosteroids (allopreganolone, THDOC) may elicit effectson on MAO expression opposite to those of glucocorticoids . It would appear that hMitChip is a reliable and novel tool that may prove useful for systematically studying the contribution of mitochondrial genomics to human health and disease.

这个项目没有做任何新的工作。自上次报告以来已经出版了两份出版物，如下所列。 慢性应激与心血管疾病、代谢综合征、神经退行性变、抑郁症和其他精神疾病以及炎症性疾病的发病机制有关。骨骼肌病和神经细胞萎缩是内源性和外源性糖皮质激素过多的常见并发症，但其潜在机制尚不清楚，有针对性的治疗干预措施有限。 线粒体在细胞内稳态中起着关键作用，包含多种代谢途径，这些代谢途径以ATP的形式产生能量。它们还产生大多数细胞活性氧种(ROS)，调节细胞程序性死亡，充当细胞凋亡的守门人。毫不奇怪，原发或继发性线粒体功能障碍与肥胖、糖尿病、癌症、神经退行性疾病、心肌病、抑郁症和衰老等疾病的发病机制有关，具有明显的公共卫生意义。患有上述疾病的患者通常使用广泛的CAM模式。 为了系统研究线粒体基因组学对人类生理和病理生理学的贡献，我们建立了一个以线粒体为中心的基因数据库，并以此为参考开发了包含501个线粒体相关核基因的定制基因芯片(HMitChip)。为了验证这种线粒体微阵列检测基因表达变化的能力，我们探索了合成糖皮质激素地塞米松(Dex)对人骨骼肌细胞线粒体核转录组的药物基因组学影响。 在hMitChip中排列的501个线粒体相关基因中，有23个(4.5%)在地塞米松处理后骨骼肌细胞出现了显著的转录变化。与胺代谢相关的基因(MAOA和SAT)在所测试的所有时间间隔内均显著上调，而参与蛋白质加工(AKAP10)、氧化磷酸化(FDX1、CyBA)、热休克细胞应激反应(HSPD1)、脂质生物合成(FACL2)、糖酵解(GCK)和线粒体蛋白质合成(TSFM)的基因仅在特定时间点显著上调。治疗7d后，脂代谢相关基因(ACADVL、ACADM)、三羧酸循环相关基因(DLST)、蛋白质加工相关基因(MPI、PPIB)和基因转录相关基因(GABPA)表达下调，而细胞凋亡相关基因(BNIP3)表达下调。分别参与细胞黏附和核苷酸代谢的CTNNA1和AK1基因在10-6M地塞米松作用7天后也显著下调。通过多次重复实验和杂交玻片的反向标记获得了可重复性的结果 对于选定的基因，hMitChip检测到的转录变化通过QRT-PCR得到证实，该转录变化在相应的微阵列实验和单独的时间进程实验中进行，在这些实验中，来自两个独立的健康男性捐赠者的心肌细胞暴露在10-6M的地塞米松中长达9天。在每个时间点都观察到了MAOA基因的显著诱导。FDX1的表达在第3天和第5天与对照细胞不同，而FACL2的表达在第5天和第5天有所不同，但没有随着时间的推移而显著增加。在地塞米松作用7天后，观察到ACADVL和ACADM有下调的趋势，这与基因芯片的结果一致，但没有达到统计学意义。选择的基因(即NNT1、TOMM70)在微阵列实验中没有差异表达，因此被用作阴性对照，其qRT-PCR结果也与微阵列的结果一致。 我们报道了儿茶酚胺代谢酶MAO-A是人骨骼肌细胞中糖皮质激素的主要靶标。MAO催化神经活性、血管活性(5-羟色胺、多巴胺、儿茶酚胺)或饮食(酪胺)胺和异物的氧化脱氨，释放活性醛和H202。糖皮质激素激活MAO-A并产生过量的过氧化氢可能是糖皮质激素引起组织氧化损伤的一条新途径，而针对该途径不同成分的MAO抑制剂或其他对抗性和CAM干预可能起到治疗作用。 遗传学研究已将MAO-A和MAO-B与人类行为的各个方面联系起来，环境相互作用调节某些MAO-A基因的表达；然而，它们在人类体内表达的激素调节仍未被探索。除了糖皮质激素外，我们已经开始研究肾上腺、性腺和神经类固醇对人胎儿星形胶质细胞MAO表达的影响。我们推测雌激素、孕激素、DHEA和/或其他神经类固醇(别孕激素，THDOC)对MAO表达的影响可能与糖皮质激素相反。 HMitChip似乎是一种可靠的新工具，可能会被证明对系统研究线粒体基因组学对人类健康和疾病的贡献有用。