Role of sphingosine-1-phosphate receptor 2 in the pathogenesis of periodontitis

1-磷酸鞘氨醇受体2在牙周炎发病机制中的作用

基本信息

批准号：
9004621
负责人：
Hong Yu
金额：
$ 11.21万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-04-01 至 2018-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9004621
关键词：
Adult Affect Alveolar Bone Loss Animal Model Animals Atherosclerosis Attenuated Bacteria Binding Bone Marrow Bone Marrow Cells Cell membrane Cells Chemotaxis Conditioned Culture Media Cre-LoxP Dinoprostone Disease Foundations G-Protein-Coupled Receptors Generations Goals Homeostasis Immune response In Vitro Infiltration Inflammatory Interleukin-1 beta Interleukin-6 Knockout Mice Leukocytes Lipids Macrophage Colony-Stimulating Factor Malignant Neoplasms Mammalian Cell Mediating Mus Oral Osteoblasts Osteoclasts Osteoporosis PTGS2 gene Pathogenesis Periodontitis Physiological Process Production Protein Kinase RNA Interference Research Rheumatoid Arthritis Rho-associated kinase Role SPHK1 enzyme Signal Pathway Signal Transduction Signaling Molecule Sphingosine-1-Phosphate Receptor System TLR4 gene TNF gene TNFSF11 gene Testing Tissues Tooth Loss United States bone bone loss cytokine eIF-2 Kinase in vivo inflammatory bone loss mRNA Expression macrophage migration monocyte new therapeutic target novel novel therapeutic intervention novel therapeutics oral pathogen osteoclastogenesis pathogen public health relevance research study response rho sphingosine 1-phosphate

项目摘要

DESCRIPTION (provided by applicant): Periodontitis is a bacteria-driven inflammatory bone loss disease affecting 47% of adults in the United States. Oral pathogens, such as Aggregatibacter actinomycetemcomitans (Aa), the pathogen associated with localized aggressive periodontitis, stimulate mammalian cells to generate and release sphingosine-1-phosphate (S1P). S1P binds to five G protein-coupled receptors, which initiates various cellular signaling pathways and affects many physiological and pathophysiological processes. However, it is unknown how S1P signaling modulates the inflammatory bone loss response induced by oral pathogens. The long-term goal is to understand the role of S1P signaling in regulating the immune response to oral pathogens and to develop a novel therapeutic strategy for periodontitis. Our preliminary study demonstrated that S1P signaling is critical in regulating the immune response to Aa. In a periodontal inflammatory bone loss animal model, deficiency in generation of S1P in mice (sphingosine kinase 1 KO mice) attenuated periodontal leukocyte infiltration and alleviated alveolar bone loss in response to Aa stimulation. Additionally, pharmacological inhibition or RNA silencing of S1P receptor 2 (S1PR2) in murine bone marrow-derived macrophages (BMM) significantly attenuated COX-2, IL-1ß, IL-6, and TNF mRNA expressions induced by Aa. Furthermore, pharmacological inhibition of S1PR2 in BM-derived preosteoclasts suppressed osteoclastogenesis induced by Aa-stimulated conditioned media. The overall objective of this application is to establish S1PR2-mediated signaling as a key modulator in regulating the immune response to the oral pathogen Aa. We hypothesize that the Aa-induced proinflammatory bone loss response is mediated through S1PR2 signaling. Blocking S1PR2 signaling will reduce proinflammatory cytokine production, attenuate osteoclastogenesis, and alleviate alveolar bone loss induced by Aa. We will test these two specific aims to determine if 1) S1PR2 deficiency in vitro will significantly decrease ERK, PLC, Rho, and NF-ĸB protein kinase activities, reduce proinflammatory cytokine production, and attenuate osteoclastogenesis in response to Aa exposure. Additionally, we will determine if blocking S1PR2 will decrease osteoclastogenic factors RANK, RANKL, and M-CSF. 2) S1PR2 deficiency in vivo will decrease periodontal leukocyte infiltration, alleviate proinflammatory cytokine production, and attenuate alveolar bone loss. Under the first aim, we will use BMM or preosteoclasts derived from S1pr2+/+ and S1pr2-/- mice to determine if S1PR2 deficiency in cells will reduce the immune response to Aa. Additionally, we will determine if blocking S1PR2 will decrease RANK, RANKL, and M-CSF induced by Aa in BMM or osteoblasts. Under the second aim, we will use an Aa-induced periodontal inflammatory bone loss animal model to determine if S1PR2 deficiency in mice will reduce the inflammatory bone loss response induced by Aa. This study will elucidate the role of S1PR2 signaling, a novel key mechanism, in the pathogenesis of periodontitis. This study will define a new therapeutic target and lay the foundation to develop a novel therapeutic strategy for periodontitis by targeting S1PR2.

描述（由申请人提供）：牙周炎是一种细菌驱动的炎症性骨质流失疾病，影响着美国 47% 的成年人。口腔病原体，例如与局部侵袭性牙周炎相关的病原体，例如放线菌聚集菌 (Aa)，会刺激哺乳动物细胞产生炎症。生成并释放 1-磷酸鞘氨醇 (S1P)，S1P 与 5 个 G 蛋白偶联。然而，S1P 信号如何调节口腔病原体引起的炎症性骨质流失反应尚不清楚，长期目标是了解 S1P 信号在调节中的作用。我们的初步研究表明，在牙周炎性骨质流失动物模型中，S1P 信号对于调节对 Aa 的免疫反应至关重要。小鼠（鞘氨醇激酶 1 KO 小鼠）中的 S1P 可以减弱 Aa 刺激引起的牙周白细胞浸润并减轻牙槽骨丢失，此外，对小鼠骨髓源性巨噬细胞 (BMM) 中的 S1P 受体 2 (S1PR2) 进行药物抑制或 RNA 沉默。显着减弱 Aa 诱导的 COX-2、IL-1ß、IL-6 和 TNF mRNA 表达。此外，BM 来源的前破骨细胞中 S1PR2 的药理学抑制可抑制 Aa 刺激的条件培养基诱导的破骨细胞生成。本申请的总体目标是建立 S1PR2 介导的信号传导作为调节口腔病原体 Aa 免疫反应的关键调节剂。继续认为，Aa 诱导的促炎性骨质流失反应是通过 S1PR2 信号传导介导的，阻断 S1PR2 信号传导将减少促炎性细胞因子的产生，减弱破骨细胞生成，并且我们将测试这两个具体目标，以确定 1) S1PR2 缺乏在体外是否会显着降低 ERK、PLC、Rho 和 NF-ĸB 蛋白激酶活性，减少促炎细胞因子的产生，并减弱破骨细胞生成。此外，我们将确定阻断 S1PR2 是否会减少破骨细胞因子 RANK、RANKL 和 M-CSF 2) S1PR2 缺乏。体内将减少牙周白细胞浸润，减轻促炎细胞因子的产生，并减少牙槽骨丢失。在第一个目标下，我们将使用源自 S1pr2+/+ 和 S1pr2-/- 小鼠的 BMM 或前破骨细胞来确定细胞中 S1PR2 缺陷是否会减少牙槽骨丢失。此外，我们将确定阻断 S1PR2 是否会降低 BMM 中 Aa 诱导的 RANK、RANKL 和 M-CSF。在第二个目标下，我们将使用 Aa 诱导的牙周炎性骨质流失动物模型来确定小鼠中 S1PR2 缺陷是否会减少 Aa 诱导的炎症性骨质流失反应。本研究将确定一个新的治疗靶点，并为针对S1PR2开发新的牙周炎治疗策略奠定基础。