Age-Related Meibomian Gland Dysfunction

年龄相关的睑板腺功能障碍

• 批准号: 8710230
• 负责人: James V Jester
• 金额: $ 37.85万
• 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/8710230
• 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.

项目总结/摘要 本项目的长期目标是了解年龄相关性睑板腺功能障碍的机制 (MGD)和蒸发性干眼症最近，我们已经表明，小鼠和人类睑板腺经历 特定的年龄相关变化，包括腺泡细胞增殖减少、腺泡萎缩和改变 过氧化物酶体增殖物激活受体γ（PPARg）在细胞质-囊泡/核中的定位 在老年小鼠和人类中，年轻人的细胞核。由于PPARg是一种脂质敏感的核受体，涉及 我们的研究结果表明，PPARg可能通过调节脂肪细胞和皮脂细胞的分化和脂肪生成， 参与调节衰老过程中的睑板腺分化。基于这些发现，我们提出， 睑板腺的老化可能导致PPARg的下调，导致睑板细胞减少， 分化和脂质合成，腺体萎缩和分泌不足的MGD。目前，有一个 关于PPARg在睑板腺功能中作用的知识存在重大空白。为了验证这一 假设我们已经开发了新成像和细胞培养系统来评估腺体体积、脂质合成 以及PPARg对它们的调节。使用非线性光学（NLO）显微镜和阵列层析成像，我们有 体积重建小鼠睑板腺，并测量总的，细胞和脂质体积， 年轻和年老的腺体。初步研究表明，老化的睑板腺萎缩涉及一个明显的 脂质体积的损失表明减少的痣细胞分化。此外，我们还使用了一致的 抗斯托克斯拉曼光谱（汽车），以确定睑板腺内的局部脂质分布， 已经初步表明，有一个年龄相关的变化，成熟的睑板腺脂质移动 从腺泡进入导管此外，我们还建立了一个SV 40永生化小鼠痣细胞系， 合成脂质并表达PPARg的细胞。利用这些新工具，我们提出以下具体目标。 （一）.建立PPARg定位和相关基因表达模式的年龄相关变化， 定量亚细胞定位、翻译后修饰和下游应答基因 在小鼠和人睑板腺中的表达模式。(2)确定老化对 通过使用NLO显微镜和阵列断层扫描定量睑板腺的体积和脂质合成 对睑板腺和汽车进行体积重建，以评估脂质成分的区域变化 存在于小鼠和人睑板腺的腺泡、小管和导管中。(3)的影响进行评估 天然和合成的PPARg配体对脂质合成的影响， 翻译修饰和下游反应基因表达模式。 (4)通过定量PPARg配体在体内的变化来测量PPARg配体对睑板细胞分化的影响。 青年和老年小鼠的PPARg表达、睑板细胞增殖、腺体体积和脂质合成 睑板腺