Age-Related Meibomian Gland Dysfunction

年龄相关的睑板腺功能障碍

• 批准号: 8527787
• 负责人: James V Jester
• 金额: $ 36.59万
• 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/8527787
• 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.

项目概要/摘要 该项目的长期目标是了解与年龄相关的睑板腺功能障碍的机制 (MGD) 和蒸发性干眼症。最近我们发现小鼠和人类睑板腺经历 特定的与年龄相关的变化，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）从细胞质-囊泡/核定位 在年老的老鼠和人类中，从年轻到有核。由于 PPARg 是一种脂质敏感的核受体， 调节脂肪细胞和皮脂细胞分化和脂肪生成，我们的研究结果表明 PPARg 可能是 参与调节衰老过程中睑板腺的分化。根据这些发现，我们建议 睑板腺老化可能导致 PPARg 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 在睑板腺功能中的作用的知识存在重大差距。为了测试这个 假设我们已经开发出新的成像和细胞培养系统来评估腺体体积、脂质合成 及其受 PPARg 的调节。使用非线性光学（NLO）显微镜和阵列断层扫描，我们有 体积重建了小鼠睑板腺并测量了总体积、细胞体积和脂质体积 年轻和年老的腺体。初步研究表明，老化的睑板腺萎缩与显着的 脂质体积的减少表明睑母细胞分化减少。此外，我们还使用了相干的 反斯托克斯拉曼光谱 (CARS) 用于识别睑板腺内的区域脂质分布 初步表明，睑板腺脂质移动的成熟度存在与年龄相关的变化 从腺泡进入导管。此外，我们还开发了SV40永生化小鼠粒细胞系 合成脂质并表达 PPARg。使用这些新颖的工具，我们提出以下具体目标。 (1).通过以下方法建立 PPARg 定位和相关基因表达模式与年龄相关的变化 量化亚细胞定位、翻译后修饰和下游反应基因 小鼠和人类睑板腺中的表达模式。 (2) 确定老化对 使用 NLO 显微镜和阵列断层扫描量化睑板腺的体积和脂质合成 体积重建睑板腺和 CARS，以评估脂质成分的区域变化 存在于小鼠和人类睑板腺的腺泡、导管和导管中。 (3) 评估效果 通过量化亚细胞定位，天然和合成的 PPARg 配体对脂质合成的影响 培养的小鼠睑细胞中的翻译修饰和下游反应基因表达模式。 (4) 通过量化 PPARg 配体对体内睑母细胞分化的影响 年轻和年老小鼠的 PPARg 表达、睑板细胞增殖、腺体体积和脂质合成 睑板腺。