Sulfide metabolism at the host microbiome interface

宿主微生物组界面的硫化物代谢

基本信息

批准号：
10151704
负责人：
David A Hanna
金额：
$ 6.6万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-01 至 2024-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10151704
关键词：
Address Affect Age Aging Air Animal Model Antioxidants Assimilations Atmosphere Behavior Biogenesis Caenorhabditis elegans Cardiovascular Physiology Cell Respiration Cells Colon Colon Carcinoma Complement Cysteine Data Development Diet Dose Electron Transport Electrons Energy Metabolism Enzymes Epigenetic Process Epithelial Cells Escherichia coli Exposure to Extravasation Foundations Genes Genetic Transcription Germ-Free Glutathione Glutathione Disulfide Histone Acetylation Histone Deacetylase Homeostasis Human Hydrogen Sulfide Hypoxia Infection Inflammation Intestines Knowledge Laboratories Larva Life Link Longevity Lysine Maintenance Mammalian Cell Mediating Metabolic Pathway Metabolism Methylation Michigan Microbe Mitochondria Modification Molecular Mus Mutation Neurons Organism Orthologous Gene Oxidation-Reduction Oxides Pathway interactions Physiological Physiological Processes Poison Post-Translational Protein Processing Process Production Proteins Proteomics RNA Interference Reporting Resistance Respiration Signal Transduction Signaling Molecule Stress Sulfate Sulfhydryl Compounds Sulfides Sulfites Sulfur Sulfur Metabolism Pathway Testing Toxic effect Translations Vasodilation Water base biological adaptation to stress cardioprotection cell type cytotoxic dietary dietary manipulation electron energy enzyme pathway gastrointestinal function genetic manipulation gut bacteria gut microbes gut microbiome histone methylation histone modification host microbiome knock-down metabolomics microbial microbiota neuroregulation oxidation persulfides respiratory response sensor sulfate reducing bacteria transcriptome sequencing transcriptomics

项目摘要

Project Summary Hydrogen sulfide (H2S) is a redox-active signaling molecule that modulates electron transport and energy metabolism, and by largely unknown mechanisms, mediates neuro- and cardioprotection, vasodilation, the hypoxic response, protein translation, epigenetics, aging, and both patho- and physiological responses in colon. As H2S is also a respiratory poison at high doses, cells actively oxidize it to produce persulfides, sulfite, thiosulfate, (collectively referred to as reactive sulfur species), and sulfate. Oxidative modification of protein cysteine thiols to persulfides is postulated to be a primary mechanism by which H2S signals. The potential involvement of other reactive sulfur species in signaling is however, unknown. Studies in our laboratory have demonstrated that H2S impacts cellular redox metabolism via its dual effects on mitochondrial energetics, i.e. increasing electron flux at low, and inhibiting it at high concentrations. The highest exposure to exogenous H2S occurs in colon (0.2–2.4 mM) and is derived from gut resident microbiota, which synthesize sulfide. Preliminary data in our laboratory reveal that colonic epithelial cells quantitatively oxidize exogenous H2S to thiosulfate, and that the localization and expression levels of sulfide oxidation enzymes in murine colonocytes are strongly influenced by the presence or absence of sulfate reducing bacteria in the gut. I hypothesize that the dynamic interplay between host and microbial sulfur metabolites influences host metabolism and impacts longevity. Using Caenorhabditis elegans as a model organism, which has the full complement of orthologous genes involved in H2S biogenesis and oxidation found in humans and is readily amenable to genetic and dietary manipulation and to life-span analyses, I will test my hypothesis by addressing the following two aims. (i) I will characterize how alterations in H2S levels and reactive sulfur species impact organismal redox and histone modifications that are linked to longevity and stress response in C. elegans. H2S levels and its oxidative byproducts will be modulated by exogenous H2S, RNA interference knockdowns of host sulfide oxidation enzymes, and by diet, using Escherichia coli with deletions in specific genes involved in sulfur metabolism. I will assess how exogenous versus dietary H2S modulation affects organismal redox using the genetically encoded reduction-oxidation sensitive GRX1-roGFP2 sensor and track changes in histone methylation and acetylation status with reported links to redox, H2S availability, diet, and aging. (ii) I will investigate how differences in exogenous H2S exposure from air versus gut microbes affects the expression and localization of host sulfide oxidation enzymes, the abundance and type of reactive sulfur species, and their effect on lifespan. I will complement these studies with metabolomic and transcriptomic analyses to identify pathways that are impacted by H2S exposure. The successful completion of these studies will be foundational to our understanding of the interplay of sulfur metabolism at the host-microbe interface.

项目概要硫化氢 (H2S) 是一种氧化还原活性信号分子，可调节电子传输和能量新陈代谢，并通过很大程度上未知的机制，介导神经和心脏保护、血管舒张、缺氧反应、蛋白质翻译、表观遗传学、衰老以及结肠的病理和生理反应。由于 H2S 在高剂量下也是一种呼吸道毒物，细胞会主动氧化它，产生过硫化物、亚硫酸盐、硫代硫酸盐（统称为活性硫物质）和硫酸盐蛋白质的氧化修饰。半胱氨酸硫醇转化为过硫化物被认为是 H2S 信号传导的主要机制。然而，我们实验室的研究还不清楚其他活性硫物种是否参与信号传导。证明 H2S 通过其对线粒体能量的双重影响来影响细胞氧化还原代谢，即低浓度时增加电子通量，高浓度时抑制电子通量。发生在结肠中 (0.2–2.4 mM)，源自肠道常驻微生物群，可合成硫化物。我们实验室的数据表明，结肠上皮细胞将外源 H2S 定量氧化为硫代硫酸盐，并且小鼠结肠细胞中硫化物氧化酶的定位和表达水平强烈受肠道中是否存在硫酸盐还原菌的影响。宿主和微生物硫代谢物之间的相互作用影响宿主代谢并影响寿命。秀丽隐杆线虫作为模式生物，具有参与的完整直系同源基因 H2S 生物合成和氧化存在于人体中，并且很容易受到遗传和饮食控制的影响对于寿命分析，我将通过解决以下两个目标来检验我的假设（i）我将描述如何进行。 H2S 水平和活性硫物质的变化会影响生物氧化还原和组蛋白修饰与线虫的寿命和应激反应相关的 H2S 水平及其氧化副产物将受到调节。通过外源 H2S、宿主硫化物氧化酶的 RNA 干扰敲低以及通过饮食，使用大肠杆菌中涉及硫代谢的特定基因缺失，我将评估外源性如何。与饮食 H2S 调节相比，使用基因编码的还原-氧化影响生物氧化还原敏感的 GRX1-roGFP2 传感器并跟踪组蛋白甲基化和乙酰化状态的变化并报告 (ii) 我将研究外源性 H2S 暴露的差异如何来自空气和肠道微生物的微生物影响宿主硫化物氧化酶的表达和定位，我将补充这些研究的活性硫物种的丰度和类型及其对寿命的影响。代谢组学和转录组学分析以确定受 H2S 暴露影响的途径。成功完成这些研究将为我们理解硫相互作用奠定基础宿主-微生物界面的代谢。