Targeting NAD metabolism to ameliorate bacterial endophthalmitis

靶向 NAD 代谢改善细菌性眼内炎

• 批准号: 10445516
• 负责人: Ashok Kumar
• 金额: $ 36.88万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10445516
• 关键词: Antibiotics; Bacterial Infections; Bioenergetics; Biosensor; Blindness; Cataract; Cell Death; Cells; Citric Acid Cycle; Communicable Diseases; Complement; Complication; Consumption; Cultured Cells; Data; Disease; Endophthalmitis; Energy Metabolism; Enzymes; Exhibits; Eye; Eye Infections; Funding; Generations; Genes; Genetic; Global Change; Goals; Homeostasis; Impairment; In Vitro; Incidence; Individual; Infection; Inflammation; Inflammatory Response; Intervention; Knockout Mice; Link; Measurement; Mediating; Metabolic; Metabolism; Mitochondria; Mus; NAD+ Nucleosidase; Natural Immunity; Niacinamide; Nicotinamide Mononucleotide; Nicotinamide adenine dinucleotide; Nicotinamide-Nucleotide Adenylyltransferase; Nicotinic Acids; Operative Surgical Procedures; Ophthalmologic Surgical Procedures; Oxidation-Reduction; Pathogenesis; Pathway interactions; Patients; Penetrating Eye Injuries; Pharmacology; Protein Kinase; RIPK1 gene; Receptor Activation; Research; Retina; Role; Severities; Signal Transduction; Sirtuins; Staphylococcus aureus; Staphylococcus aureus infection; Supplementation; Testing; Therapeutic; Tissues; Vision; aging population; bacterial endophthalmitis; cell type; gene therapy; insight; intravitreal injection; metabolomics; mouse genetics; nicotinamide phosphoribosyltransferase; overexpression; pathogen; prevent; restoration; therapeutic target; tool; transcriptomics; treatment strategy

Project Summary Bacterial endophthalmitis is a vision-threatening complication commonly occurring post penetrating eye injuries and ocular surgeries. Despite aggressive antibiotics and surgical interventions, endophthalmitis often results in partial or complete vision loss. The long-term goal of our research has been to study the pathobiology of endophthalmitis and identify potential therapeutic targets for treatment. In our recent study (PMID: 34095879), using transcriptomics and untargeted metabolomics, we identified several key pathways related to energy metabolism being perturbed during Staphylococcus aureus (SA) endophthalmitis. Among these pathways, we found that bacterial infection rapidly depletes the nicotinamide adenine dinucleotide (NAD+) pool in the mouse retina. NAD+ is not only crucial for oxidation-reduction reactions in the mitochondria, but metabolites of the NAD+ pathway also serve as substrates for various enzymes (e.g., PARPs, sirtuins, and CD38) to maintain cellular homeostasis. Thus, dysregulation in NAD+ metabolism has emerged as a contributing factor in the pathogenesis of several diseases. However, its role has not been investigated in ocular infections. Here, we propose that NAD+ depletion causes bioenergetics collapse, leading to the activation of receptor-interacting protein kinase-3 (RIPK3) mediated retinal cell death. In support, our preliminary data show disruption of the NAD+ synthesis via salvage pathway, increased activity of CD38 NADase, and the activation of RIPK3/MLKL signaling in SA-infected retina and cultured cells. Using a combination of mouse genetic tools, gene therapy, and pharmacological interventions, we will determine mechanisms of NAD+ depletion and restoration of salvage pathway (Aim 1), elucidate the crosstalk between CD38 NADase activity and RIPK3 in regulating retinal cell death (Aim 2), and test the hypothesis whether supplementation of NAD+ precursors can be used as an adjunct therapy to treat bacterial endophthalmitis (Aim 3). Collectively, the mechanistic insights on NAD+ dysregulation and NAD+ supplementation treatment strategies developed in this proposal could have a major impact in the field, not only with regards to ocular infections but other systemic infectious diseases as well.

项目摘要 细菌性内膜膜是一种威胁性的并发症，通常发生后穿透眼损伤 和眼科手术。尽管有侵略性抗生素和手术干预措施，但内脑炎经常导致 部分或完全视力丧失。我们研究的长期目标是研究 内嗜性并确定潜在的治疗靶标的治疗靶标。在我们最近的研究（PMID：34095879）中， 使用转录组学和非靶向代谢组学，我们确定了与能量有关的几个关键途径 在金黄色葡萄球菌（SA）内膜炎期间，代谢受到干扰。在这些途径中，我们 发现细菌感染迅速耗尽了小鼠中的烟酰胺腺苷二核苷酸（NAD+）池 视网膜。 NAD+不仅对于线粒体中的氧化还原反应至关重要，而且对于NAD+的代谢产物至关重要 途径还用作各种酶（例如PARP，Sirtuins和CD38）的底物以维持细胞 稳态。因此，NAD+代谢的失调已成为发病机理的一个促成因素 几种疾病。但是，其作用尚未在眼部感染中进行研究。在这里，我们建议NAD+ 耗竭会导致生物能塌陷，导致受体相互作用蛋白激酶3 （RIPK3）介导的视网膜细胞死亡。为了支持，我们的初步数据显示了通过 打捞途径，CD38 NADase的活性增加以及RIPK3/MLKL信号的激活 视网膜和培养细胞。结合小鼠遗传工具，基因治疗和药理 干预措施，我们将确定NAD+耗竭和挽救途径的恢复的机制（AIM 1）， 在调节视网膜细胞死亡中，阐明CD38 NADase活性与RIPK3之间的串扰（AIM 2）和 测试假设是否补充NAD+前体可以用作治疗的辅助疗法 细菌性内膜菌（AIM 3）。总体而言，关于NAD+失调和NAD+的机械见解 该提案中制定的补充治疗策略可能会对该领域产生重大影响，而不仅仅是 关于眼部感染，但其他全身感染性疾病也是如此。