Detection of S-(2-succino)cysteine (2SC) as a Biomarker of Mitochondrial Disease

检测 S-(2-琥珀酰)半胱氨酸 (2SC) 作为线粒体疾病的生物标志物

基本信息

批准号：
8571892
负责人：
Norma Frizzell
金额：
$ 6.85万
依托单位：
UNIVERSITY OF SOUTH CAROLINA AT COLUMBIA
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-01 至 2015-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8571892
关键词：
5 year old Accounting Adipocytes Adipose tissue Affect Antibodies Antioxidants Biochemical Bioenergetics Biological Markers Brain Stem Cells Chemicals Citric Acid Cycle Clinical Clinical Treatment Complex Cysteine Cytochrome c Reductase DNA Data Defect Detection Developmental Delay Disorders Diabetes Mellitus Diabetic mouse Diagnosis Diagnostic Disease Early Diagnosis Electron Transport Electrons Embryo Enzymes Event Failure Feedback Fibroblasts Fumarates Future Genes Genetic Glucose Hormones Infant Insulin Knock-out Knockout Mice Lateral Leigh Disease Life Link Live Birth Mass Fragmentography Measurement Measures Membrane Potentials Metabolic Methylene blue Mitochondria Mitochondrial Diseases Mitochondrial Encephalomyopathies Modeling Modification Mus Mutation NADH Neonatal Screening Nerve Degeneration Neurodegenerative Disorders Newborn Infant Nuclear Nutrient Oxidative Phosphorylation Oxidative Phosphorylation Deficiency Oxidoreductase Pathology Patients Peptides Phenotype Post-Translational Protein Processing Proteins Reaction Regulation Rest Sampling Screening procedure Selenium Selenocysteine Serum Serum Proteins Stress Structure Sulfhydryl Compounds Symptoms Testing Therapeutic Therapeutic Intervention Translating Urine Work adiponectin design diabetic disease phenotype genetic analysis improved innovation liquid chromatography mass spectrometry mitochondrial membrane mouse model neuropathology novel novel therapeutics oxidation prevent public health relevance selenoprotein

项目摘要

DESCRIPTION (provided by applicant): Mitochondrial diseases occur at a rate of 1 in 5000 live births and are often fatal by ~5 years old. These mitochondrial encephalomyopathies are usually oxidative phosphorylation (OXPHOS) disorders in which one or more components of the electron transport chain (ETC) are no longer operating efficiently to synthesize ATP. Although genetic sequencing has identified >200 of the underlying causative mutations in mitochondrial or nuclear DNA, a definitive biochemical link between the genetic defect and the neurodegenerative pathology remains to be elucidated. As a result there are no accurate disease biomarkers and infants are often initially identified as a result of their failure to thriv or by the existence of severe developmental delays. The innovative studies proposed here are expected to reveal a novel metabolic link between reduced OXPHOS and neuropathology, and may have utility to act as a diagnostic biomarker of mitochondrial disease. Previously, we have detected a new chemical modification of proteins in diabetes, S-(2-succino)cysteine (2SC), which is formed by reaction of the Krebs cycle intermediate fumarate with reactive cysteine residues in protein. Both fumarate and protein succination are increased in adipocytes cultured in high glucose and in diabetic mouse adipose tissue. We have shown that increased succination can significantly affect protein regulation by lowering enzymatic activity and interfering with the secretory structure of hormones. In diabetes, the increase in 2SC-modified proteins occurs as a result of nutrient excess, accumulation of NADH, and feedback inhibition of the Krebs cycle dehydrogenases, allowing the increase in fumarate. In a novel, lateral extension of these observations we propose that a similar ETC inhibition e.g. as a consequence of Complex I deficiency during Leigh Syndrome, would result in increased NADH, fumarate and protein succination in mitochondrial disease. In Preliminary Data, we demonstrate that increased protein succination is detectable on a range of proteins in the brainstem of a mouse model of Leigh syndrome (Ndufs4 knockout) in association with neuropathology. We hypothesize that the increased 2SC levels are also detectable in serum or urine during Leigh syndrome and may provide a more useful measure of metabolic derangement in the newborn than the current lactate measurements. In this study we will optimize the measurement of 2SC in serum and urine to determine its usefulness as a biomarker of OXPHOS deficiencies. We will also explore a therapeutic intervention which should lower NADH levels, reduce fumarate and thereby prevent increased protein succination, opening novel therapeutic avenues for the future treatment of mitochondrial diseases.

描述（由申请人提供）：线粒体疾病的发生率为5000分之1，通常是致命的5岁。这些线粒体脑膜病通常是氧化磷酸化（OXPHOS）疾病，其中电子传输链（ETC）的一个或多个成分不再有效地合成ATP。尽管遗传测序已经确定了线粒体或核DNA中的基本原因突变的> 200，但仍有待阐明遗传缺陷与神经退行性病理学之间的明确生化联系。结果，通常没有准确的疾病生物标志物，并且婴儿通常是由于未能达到或存在严重的发育延迟而被确定的。预计此处提出的创新研究将揭示出降低的Oxphos和神经病理学之间的新陈代谢联系，并可能充当线粒体疾病的诊断生物标志物。以前，我们已经检测到糖尿病中蛋白质的新化学修饰，S-（2-核）半胱氨酸（2SC）是由Krebs循环中间富马酸酸酯中间富马酸酯与蛋白质中反应性半胱氨酸残基的反应形成的。在高葡萄糖和糖尿病小鼠脂肪组织中培养的脂肪细胞中，富马酸盐和蛋白质效果都增加了。我们已经表明，增加的琥珀酸可以通过降低酶活性并干扰激素的分泌结构来显着影响蛋白质调节。在糖尿病中，由于营养过量，NADH的积累以及Krebs循环循环脱氢酶的反馈抑制，2SC修饰蛋白的增加发生，从而允许富马酸盐的增加。在这些观察结果的小说，横向延伸中，我们提出类似的等等抑制作用，例如由于Leigh综合征的复杂缺乏症，将导致线粒体疾病中的NADH，富马酸盐和蛋白质效果增加。在初步数据中，我们证明，在与神经病理学相关的Leigh综合征（NDUFS4敲除）小鼠模型的脑干中，可以检测到蛋白质的增加。我们假设在利综合症期间，在血清或尿液中还可以检测到增加的2SC水平，并且可能比当前的乳酸测量值提供了代谢危险的更有用的量度。在这项研究中，我们将优化血清和尿液中2SC的测量，以确定其作为Oxphos缺陷的生物标志物的有用性。我们还将探索一种治疗性干预措施，该干预措施应降低NADH水平，降低富马酸盐，从而防止蛋白质的增加，开辟新的治疗途径，以供未来的线粒体疾病治疗。