Age-Related Meibomian Gland Dysfunction

年龄相关的睑板腺功能障碍

• 批准号: 8334615
• 负责人: James V Jester
• 金额: $ 38.4万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-30 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8334615
• 关键词: Acinar Cell; Acinus organ component; Adipocytes; Aging; Agonist; Apoptosis; Atrophic; Binding; Cell Culture System; Cell Line; Cell Nucleus; Cell Proliferation; Cells; Cytoplasm; Development; Down-Regulation; Duct (organ) structure; Eye diseases; Eyelid Diseases; Eyelid structure; Gene Expression; Gene Expression Profile; Genes; Gland; Goals; Human; Image; Knowledge; Ligands; Lipids; Measures; Microscopy; Molecular; Mus; Nuclear; Nuclear Receptors; Operative Surgical Procedures; Optics; PPAR gamma; Phosphorylation; Population; Post-Translational Protein Processing; Prevalence; Raman Spectrum Analysis; Recruitment Activity; Regulation; Role; Serine; Simian virus 40; Testing; Tissues; Western Blotting; abstracting; age effect; age related; aging population; base; eye dryness; human NCOR1 protein; in vivo; lipid biosynthesis; meibomian gland; meibomian gland dysfunction; novel; novel therapeutics; promoter; receptor; response; tomography; tool

Project Summary/Abstract The long-term goal of this project is to understand the mechanism of age-related meibomian gland dysfunction (MGD) and evaporative Dry Eye. Recently we have shown that mouse and human meibomian glands undergo specific age-related changes including decreased acinar cell proliferation, acinar atrophy, and altered peroxisome proliferator-activated receptor gamma (PPARg) localization from cytoplasmic-vesicluar/nuclear in young to nuclear in old mice and humans. Since PPARg is a lipid sensitive, nuclear receptor implicated in regulating adipocyte and sebocyte differentiation and lipogenesis, our findings suggest that PPARg may be involved in modulating meibomian gland differentiation during aging. Based on these findings we propose that aging of the meibomian gland may result in down-regulation of PPARg leading to decreased meibocyte differentiation and lipid synthesis, gland atrophy, and a hyposecretory MGD. Currently, there is a MAJOR GAP in knowledge regarding the role of PPARg in meibomian gland function. To test this hypothesis we have develop novel imaging and cell culture systems to assess gland volume, lipid synthesis and their regulation by PPARg. Using non-linear optical (NLO) microscopy and array tomography we have volumetrically reconstructed the mouse meibomian gland and measured total, cellular and lipid volumes in young and old glands. Preliminary studies suggest that atrophy of aging meibomian glands involves a marked loss in the lipid volume suggesting decreased meibocyte differentiation. Additionally, we have used coherent anti-stokes raman spectroscopy (CARS) to identify the regional lipid profiles within the meibomian gland and have tentatively shown that there is an age-related change in the maturation of meibomian gland lipids moving from the acini into the duct. Furthermore, we have developed an SV40 immortalized mouse meibocyte cell line that synthesizes lipids and expresses PPARg. Using these novel tools we propose the following Specific Aims. (1). Establish the age-related changes in PPARg localization and associated gene expression patterns by quantifying the subcellular localization, post-translational modification and downstream response gene expression patterns in the mouse and human meibomian gland. (2) Determine the effects of aging on the meibomian gland by quantifying the volume and lipid synthesis using NLO microscopy and array tomography to volumetrically reconstruct the meibomian gland and CARS to assess regional changes in lipid components present in the acini, ductule and duct of the mouse and human meibomian gland. (3) Assess the effects of natural and synthetic PPARg ligands on lipid synthesis by quantifying the subcellular localization, post- translational modification and downstream response gene expression patterns in cultured mouse meibocytes. (4) Measure the effect of PPARg ligands on meibocyte differentiation in vivo by quantifying the changes in PPARg expression, meibocyte proliferation, gland volume and lipid synthesis in young and old mouse meibomian glands.

项目摘要/摘要 该项目的长期目标是了解与年龄相关的Meibomian腺功能障碍的机制 （MGD）和蒸发干眼。最近，我们表明鼠标和人类梅博姆腺发生 与年龄相关的特定变化，包括减少腺泡细胞增殖，腺泡萎缩和改变 过氧化物酶体增殖物激活的受体伽马（PPARG）来自细胞质 - vesicluar/核中的定位 老鼠和人类的核向核。由于PPARG是一种脂质敏感的，因此核受体与 调节脂肪细胞和皮脂细胞分化和脂肪形成，我们的发现表明PPARG可能是 参与衰老期间调节Meibomian腺体分化。根据这些发现，我们建议 Meibomian腺老化可能会导致PPARG下调导致Meibococyte降低 分化和脂质合成，腺体萎缩和降压MGD。目前，有一个 关于PPARG在Meibomian腺功能中的作用的知识的主要差距。测试这个 假设我们开发了新型的成像和细胞培养系统，以评估腺体积，脂质合成 以及他们对PPARG的调节。使用非线性光学（NLO）显微镜和阵列层析成像，我们有 体积重建小鼠梅博米亚腺，并测量总计，细胞和脂质体积 年轻人和老腺。初步研究表明，衰老的Meibomian腺体萎缩涉及明显的 脂质体积的损失表明级质细胞分化降低。另外，我们使用了连贯的 反stokes拉曼光谱法（CARS），以识别梅博米亚腺内的区域脂质谱。 暂时表明，Meibomian腺体脂质运动的成熟与年龄有关 从acini到管道。此外，我们已经开发了SV40永生的小鼠Meibocyte细胞系 这可以合成脂质并表达PPARG。使用这些新颖的工具，我们提出以下特定目标。 （1）。确定与年龄相关的PPARG定位和相关基因表达模式的变化 量化亚细胞定位，翻译后修饰和下游反应基因 小鼠和人类肠腺中的表达模式。 （2）确定衰老对 通过使用NLO显微镜和阵列断层扫描来量化体积和脂质合成，通过量子腺腺体 体积重建Meibomian腺体和汽车以评估脂质成分的区域变化 存在于小鼠和人肠腺的acini，导管和导管中。 （3）评估 通过量化亚细胞定位的脂质合成的天然和合成PPARG配体 培养的小鼠Meibibocytes中的翻译修饰和下游反应基因表达模式。 （4）测量PPARG配体对体内米布细胞分化的影响，通过量化的变化 PPARG表达，Meibocyte增殖，年轻小鼠和老鼠的腺体体积和脂质合成 Meibomian腺体。