The Role of Glutamine Metabolism for P. gingivalis-Induced Non-Canonical Autophagy in Epithelial Cells

谷氨酰胺代谢对牙龈卟啉单胞菌诱导的上皮细胞非典型自噬的作用

• 批准号: 10537625
• 负责人: Bridgette Frances Wellslager
• 金额: $ 4.76万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10537625
• 关键词: Affect; Amino Acids; Anaerobic Bacteria; Antioxidants; Autophagocytosis; Autophagosome; Bacteria; Biogenesis; Biology; Cell physiology; Cells; Chronic; Chronic Disease; Complex; Coupling; Critical Pathways; Data; Degradation Pathway; Dependence; Development; Disease; Elements; Endoplasmic Reticulum; Environment; Epithelial; Epithelial Cells; Event; Fellowship; Fostering; Foundations; GTP-Binding Protein alpha Subunits, Gs; Gene Proteins; Generations; Gingiva; Glutamine; Glutathione; Goals; Homeostasis; Human; Immune; Impairment; Infection; Knowledge; Life; Lipids; Maintenance; Mediating; Membrane; Metabolic; Metabolic Pathway; Metabolism; Microtubule-Associated Proteins; Molecular; Mucous Membrane; Oral; Oral cavity; Oral health; Oral mucous membrane structure; Oxidation-Reduction; Oxidative Stress; Pathway interactions; Periodontitis; Porphyromonas gingivalis; Production; Protein Isoforms; Publishing; Recycling; Regulation; Research; Role; Route; Scientist; Secure; Testing; Time; Training; Ultraviolet Rays; Vacuole; Variant; amino acid metabolism; antimicrobial; cellular pathology; combat; dysbiosis; glutathione peroxidase; microbial; microorganism; molecular phenotype; new therapeutic target; novel; novel therapeutics; oral biology; pathobiont; pathogen; radiation resistance; recruit; therapeutically effective

Growing evidence underlines that Glutamine (Gln) metabolism can influence key metabolic and autophagic cellular events. Porphyromonas gingivalis (P.g) is a major periodontopathic, fastidious, pathobiont and successful colonizer of gingival mucosa, which has recently been identified to induce a special form of autophagy in human gingival epithelial cells (GECs). While GECs function as an intrinsically important first line of immune defense of the gingiva, GECs can be exploited by P.g for securing a successful persistence niche in the oral mucosa and a potential systemic dissemination route. Despite the growing evidence pinpointing that altered Gln metabolism can contribute to cellular pathologies, knowledge gaps remain regarding how host Gln metabolism could be influenced by bacteria to regulate host redox homeostasis and potentially promote bacterial survival in the GECs. Recently, we discovered that P.g steadily increases robust Glutathione (GSH) production in GECs to combat host-mediated oxidative stress-driven pathogen clearance. Our novel findings, for the first time, show that P.g infection alters host Gln metabolism, a component of GSH synthesis, in GECs. In addition, we recently demonstrated that P.g induces a pro-bacterial form of autophagy in GECs, where Endoplasmic Reticulum-rich (ER)/Microtubule-associated protein 1A/1B-light chain 3 (LC3) double membrane autophagosomes act as replicative niches for P.g and protect the bacteria from antimicrobial degradation pathways. Our novel data shows that the biogenesis and maintenance of these P.g-containing autophagosomes is dependent on the critical redox molecule, Glutathione Peroxidase 1 (GpX1). The dependency on GpX1 can be markedly altered by increasing free Gln levels in GECs' cellular environment. Thus, our overarching hypothesis for this proposal is that P.g alters host Gln metabolism in GECs to maintain host redox homeostasis and specifically contributes to the biogenesis of a GpX1-driven, pro-bacterial form of autophagy. Two Specific Aims are proposed to test this hypothesis. Aim 1 will characterize the phenotypic molecular events occurring during P.g infection that specifically associate with host cell Gln metabolism and the host cell redox state, allowing for the intracellular survival of P.g in GECs. Aim 2 will mechanistically determine the molecular interactome involved in P.g-induced autophagy through the modulation of host Gln metabolism in GECs. These collectively will identify what elements of the Gln metabolic pathways are critical for the autophagic survival of P.g in GECs, and will elucidate the specific molecular machineries involved in pro-bacterial autophagy driven by changes in host Gln metabolism upon P.g infection. Overall, this proposal will contribute to the identification of novel targeted therapeutic strategies to control the chronic intracellular colonization of P.g in the oral mucosa and beyond. Receiving the F31 Fellowship for this proposal will further the applicant's research goals, critically contribute to her training in the field of Oral Biology, and will foster her unique development as an oral health academic scientist.

越来越多的证据强调谷氨酰胺（GLN）代谢会影响关键的新陈代谢和自噬 细胞事件。牙龈卟啉单胞菌（P.G）是一种主要的牙周病，挑剔，病原体和 牙龈粘膜的成功殖民者，最近已确定诱导一种特殊形式 人牙龈上皮细胞（GEC）中的自噬。而GEC则是本质上重要的第一行 为了防御牙龈的免疫防御，P.G可以利用GEC来确保成功的持久性利基市场 口腔粘膜和潜在的全身传播途径。尽管有越来越多的证据表明 GLN代谢改变可能有助于细胞病理，知识差距仍然存在有关宿主GLN的知识差距 代谢可能会受到细菌的影响，以调节宿主氧化还原稳态并有可能促进 GEC中的细菌生存。最近，我们发现P.G稳步增加了强大的谷胱甘肽（GSH） 在GEC中产生以对抗宿主介导的氧化应激驱动的病原体清除率。我们的小说发现， 首次表明P.G感染改变了GEC中GSH合成的一个组成部分的宿主GLN代谢。 此外，我们最近证明了P.G在GEC中诱导了一种促细菌形式，其中 内质网（ER）/微管相关蛋白1a/1b-light链3（LC3）双膜 自噬体充当P.G的复制生态位，并保护细菌免受抗菌降解 途径。我们的新数据表明，这些含P.G的生物发生和维持 自噬体取决于临界氧化还原分子，谷胱甘肽过氧化物酶1（GPX1）。这 通过在GEC的细胞环境中增加自由GLN水平可以显着改变对GPX1的依赖性。 因此，我们对该提案的总体假设是，P.G将GEC中的宿主GLN代谢改变为 保持宿主氧化还原稳态，并特别有助于GPX1驱动的促细菌的生物发生 自噬的形式。提出了两个具体目标来检验这一假设。 AIM 1将表征 在P.G感染期间发生的表型分子事件与宿主细胞GLN特别相关 代谢和宿主细胞氧化还原态，允许P.G在GEC中的细胞内存活。 AIM 2意志 机械师通过 GEC中宿主GLN代谢的调节。这些共同确定GLN代谢的元素 途径对于P.G在GEC中的自噬存活至关重要，并将阐明特定的分子 P.G感染后宿主GLN代谢的变化驱动的亲细菌自噬的机器。 总体而言，该建议将有助于确定新颖的有针对性的治疗策略以控制 口腔粘膜及其他地区P.G的慢性细胞内定植。接受F31奖学金 提案将进一步进一步申请人的研究目标，为她在口头领域的培训做出了重大贡献 生物学，并将促进她作为口腔健康学术科学家的独特发展。