Thy1 expression, adpogenesis, inflammation and orbital remodeling mechanisms in Thyroid Eye Disease

甲状腺眼病中 Thy1 表达、脂肪生成、炎症和眼眶重塑机制

• 批准号: 9213038
• 负责人: RICHARD P. PHIPPS
• 金额: $ 38.46万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-01 至 2020-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9213038
• 关键词: Adipocytes; Alpha Cell; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Antibodies; Area; Autoantigens; Autoimmune Diseases; Biological Assay; Biological Process; Blindness; Cell Surface Proteins; Cell surface; Cells; Cicatrix; Clustered Regularly Interspaced Short Palindromic Repeats; Complementary DNA; Connective Tissue; Deposition; Development; Diplopia; Disease; Equilibrium; Evidence based treatment; Eye; Eye diseases; Fatty acid glycerol esters; Fc Receptor; Fibroblasts; Gene Expression; Gene Expression Profiling; Genetic Transcription; Goals; Graves' Disease; Homeostasis; Human; Impairment; Inflammation; Inflammatory; Ligands; Link; Lipids; Mediating; Mediator of activation protein; Methods; MicroRNAs; Molecular; Myofibroblast; Ocular orbit; Orbital Diseases; Outcome; Patients; Peroxisome Proliferator-Activated Receptors; Phenotype; Plasmids; Post-Translational Protein Processing; Process; Production; Receptor Activation; Receptor Signaling; Regulation; Reporter; Research; Research Project Grants; Role; Signal Transduction; Small Interfering RNA; Stimulus; Testing; Therapeutic Intervention; Thyroid Gland; Thyrotropin Receptor; Tissues; Transcriptional Activation; Translations; Treatment Efficacy; Vision; Work; cytokine; experimental study; human disease; inhibitor/antagonist; lipid biosynthesis; overexpression; receptor expression; response; thyroid associated ophthalmopathies; transcription factor

The Focus: Thyroid eye disease (TED) is a disfiguring and sight-threatening autoimmune disease that involves inflammation and remodeling of the orbit. TED can present itself with mostly orbital fat (Type 1), orbital connective tissue (Type 2) or a combination of both. Here, we focus on how TED manifests itself as Type 1 disease. The Premise: We know that activated orbital fibroblasts produce high levels of inflammatory cytokines and form either connective tissue myofibroblasts or lipid rich inflammatory adipocytes. Our earlier work showed - that only human orbital fibroblasts that do not express a cell surface protein called Thy1 (Thy1 ) can differentiate into adipocytes when stimulated with an adipogenic medium. And, only those that express Thy1 (Thy1+) differentiate into myofibroblasts when provoked by pro-scarring agents like TGF. Herein, we show that Thy1 presence has a direct role in diminishing orbital fibroblast fat accumulation. For example, deliberate - expression of Thy1 in Thy1 fibroblasts blocks their differentiation to adipocytes. Since adipogenesis requires the activation of the transcription factor PPAR we propose that Thy1 impairs PPAR function. Adipogenesis can also manifest after thyroid stimulating hormone receptor (TSHR) signaling and our studies demonstrate that Thy1 and TSHR are inversely related. Goals: (a) test specific hypotheses about mechanistic and causal roles of Thy1 in TED, (b) determine the molecular mechanisms by which Thy1 expression dampens adipogenesis and inflammatory cytokine production. These mechanisms include [1] regulation of TSHR, [2] PPAR activity and [3] modulation of post-transcriptional gene expression through key microRNAs. Organizing Hypotheses: Thy1 is more than a cell-surface marker in TED, as it is also a functional mediator of fibroblast fate in the disease. Thy1+ orbital fibroblasts have decreased PPAR activity, decreased TSHR, and decreased miR-130a expression, which inhibit the fundamental processes in TED of orbital fibroblast adipogenesis and proinflammatory cytokine production. The proposed experiments will test corollaries of this hypothesis using primary human orbital fibroblasts and tissues; because there is no animal model that provides a consistent phenotype of fat accumulation in the orbit. Specific Aim 1: Test the hypothesis that orbital fibroblast Thy1 has anti-adipogenic and anti-inflammatory mechanisms of action by inhibiting PPAR activity and regulating post-transcriptional gene expression. Specific Aim 2: Test the hypothesis that the mechanism by which Thy1 has its anti-adipogenic and anti-inflammatory effects is through the regulation of TSHR. Impact on the field: Discovering that Thy1 has a major biological function influencing eye disease is a major advance opening new areas for research and therapeutic intervention into the aberrant fat deposition and inflammation associated with TED. The inverse relationship that will be investigated between Thy1 and TSHR is the first demonstration that Thy1 can control TSHR. The results will lead to further research on how targeting of Thy1 and/or its anti-adipogenic mechanism of action could be used in more effective therapeutics.

焦点：甲状腺眼病（TED）是一种毁容和威胁视力的自身免疫性疾病， 包括炎症和眼眶重塑TED可以表现为主要是眼眶脂肪（1型）， 结缔组织（2型）或两者的组合。在这里，我们关注TED如何表现为类型1 疾病假设：我们知道激活的眼眶成纤维细胞产生高水平的炎症细胞因子 并形成结缔组织肌成纤维细胞或富含脂质的炎性脂肪细胞。我们之前的研究表明 - 只有不表达细胞表面蛋白Thy 1（Thy 1）的人类眼眶成纤维细胞， 当用脂肪形成培养基刺激时，细胞分化成脂肪细胞。只有那些表达Thy 1的细胞 (Thy1+）当由促瘢痕形成剂如TGF β 1引起时分化成肌成纤维细胞。在此，我们表明， Thy 1的存在在减少眼眶成纤维细胞脂肪积累中具有直接作用。例如，故意 - Thy 1成纤维细胞中Thy 1的表达阻断了它们向脂肪细胞的分化。由于脂肪生成需要 转录因子PPAR γ的激活，我们认为Thy 1削弱了PPAR γ的功能。脂肪形成 也可以在促甲状腺激素受体（TSHR）信号传导后出现，我们的研究表明， Thy 1和TSHR呈负相关。目标：（a）测试关于机械和因果作用的特定假设 TED中Thy 1的表达，（B）确定Thy 1表达抑制脂肪形成的分子机制 和炎性细胞因子的产生。这些机制包括[1] TSHR的调节，[2] PPAR γ活性 和[3]通过关键microRNA调节转录后基因表达。组织假设： Thy 1不仅仅是TED中的细胞表面标记物，因为它也是TED中成纤维细胞命运的功能性介导物。 疾病Thy 1+眼眶成纤维细胞具有降低的PPAR γ活性、降低的TSHR和降低的miR-130 a 表达，其抑制TED中眼眶成纤维细胞脂肪形成的基本过程， 促炎细胞因子的产生。拟议的实验将测试这一假设的推论， 原代人眼眶成纤维细胞和组织;因为没有动物模型提供一致的 脂肪堆积在眼眶中的表型。具体目标1：检验眼眶成纤维细胞Thy 1具有以下功能的假设： 通过抑制过氧化物酶体增殖物激活受体（PPAR）活性和调节 转录后基因表达。具体目标2：检验Thy 1 其抗脂肪形成和抗炎作用是通过调节TSHR。对外地的影响： 发现Thy 1具有影响眼部疾病的主要生物学功能是一个重大进展， 异常脂肪沉积和炎症相关的研究和治疗干预领域 和TED。将要研究的Thy 1和TSHR之间的反比关系是第一个证明 Thy 1可以控制TSHR这些结果将导致进一步研究Thy 1和/或其靶向作用如何影响细胞的功能。 抗脂肪形成作用机制可用于更有效的治疗。