Role of lacrimal gland myoepithelial cells in dry eye disease

泪腺肌上皮细胞在干眼病中的作用

基本信息

批准号：
10553199
负责人：
DRISS ZOUKHRI
金额：
$ 48.38万
依托单位：
TUFTS UNIVERSITY BOSTON
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10553199
关键词：
Acinar Cell Acinus organ component Actins Age Animal Model Atrophic Autoimmune Candidate Disease Gene Catabolism Cell Separation Cell physiology Cells Chronic Contractile Proteins Contracts Coupling Data Denervation Disease Down-Regulation Dry Eye Syndromes Ductal Epithelial Cell Efferent Neurons G-Protein-Coupled Receptors GTP-Binding Proteins Gene Expression Genes Gland Goals Health Human Impairment In Vitro Inflammation Inflammatory Interleukin-1 Knock-out Knowledge Lacrimal gland structure Lead MAPK8 gene MMP2 gene Mammary gland Mediating Metalloproteases Microfilaments Molecular Mus Muscle Muscle Proteins Muscle denervation procedure Muscular Atrophy Myoepithelial cell N-terminal Neuropeptides Output Oxytocin Oxytocin Receptor Pathogenesis Pathway interactions Phosphotransferases Process Production Proteins Proteomics RNA Receptor Cell Receptor Signaling Reporting Role Second Messenger Systems Signal Transduction Signal Transduction Pathway Sjogren&apos s Syndrome Smooth Muscle Smooth Muscle Myocytes Sorting Stress System Techniques Tissues Translating Ubiquitin aqueous calponin cell type cytokine mammary milk production milk secretion multicatalytic endopeptidase complex muscular system neural neurotransmitter release new therapeutic target novel protein expression receptor receptor expression response sex transcriptome sequencing

项目摘要

Chronic inflammation of the lacrimal gland (LG), as occurs in Sjögren’s syndrome, is the leading cause of aqueous- deficient dry eye disease (DED). The mechanisms leading to insufficient LG secretion are still not completely understood. The LG is composed of acinar, myoepithelial, and ductal cells, with acini and myoepithelial cells (MEC) forming the secretory units. MECs express several muscle proteins, such as alpha smooth muscle actin (SMA) and calponin, and are therefore able to contract. MECs are best studied in the mammary gland where their contraction is shown to be crucial for milk production and contraction is mainly controlled by the neuropeptide oxytocin. Despite their potential critical role in LG secretion, very little is known about MEC contraction in this tissue, nor is the impact of chronic inflammation of the LG on these cells. One of goals of the current proposal is to fill this gap in knowledge. Our preliminary studies show that murine and human LG MECs express the oxytocin receptor (OXTR) and contract in response to oxytocin stimulation. Furthermore, we show that MECs in chronically inflamed LG are atrophied, with down-regulation of contractile proteins SMA and calponin and the OXTR and MECs from these glands do not contract in response to oxytocin stimulation. We previously reported that interleukin-1 (IL-1) inhibits neurotransmitter release from LG efferent nerves leading to DED. We also reported activation of the stress activated c-Jun N-terminal kinase (JNK) and metalloproteinases 2 (MMP2) in chronically inflamed LGs and that inhibition of either pathway restored LG secretion and tears output in animal models of DED. Numerous studies showed that denervation of muscle tissues leads to tissue atrophy and degradation of muscle contractile proteins via the ubiquitin/proteasome pathways. Based on these findings, we hypothesize that in chronic DED, proinflammatory cytokines inhibit neurotransmitter release from LG efferent nerves creating a denervated-like tissue and that they trigger degradation of the OXTR and MEC myofilament proteins. This degradation translates into a loss of contractibility of MECs thus further exacerbating the effect of the loss of neural input on the secretory units of the LG. We further hypothesize that the JNK, MMP2, and ubiquitin/proteasome pathways mediate the effects of proinflammatory cytokines on MEC functions. We will use both in vitro (sorted MEC cells) as well as animal models of DED to investigate how proinflammatory cytokines interfere with oxytocin-induced contraction of LG MECs. We will use unbiased RNA-seq and quantitative global proteomics techniques to identify novel pathways that are altered in MECs in chronically inflamed LGs. At the completion of these studies, we will have established a role for the MEC, an important and yet understudied cell in the LG, and the oxytocin signaling system in the pathogenesis of aqueous-deficient DED and identified potential novel therapeutic targets.

如Sjögren综合征所发生的那样，泪腺（LG）的慢性炎症是水性水的主要原因干眼症不足（DED）。导致LG分泌不足的机制仍未完全了解。 LG由形成秘书单位的腺泡，肌上皮和导管细胞组成。 MEC表达几种肌肉蛋白，例如α平滑肌肌动蛋白（SMA）和钙蛋白酶，因此能够收缩。最好在乳腺中研究MEC，在乳腺中，其合同证明对牛奶的生产至关重要，并且收缩主要受神经肽催产素的控制。尽管在LG分泌中它们的潜在关键作用，但对该组织中的MEC收缩知之甚少，LG慢性感染对这些细胞的影响也不是什么。当前建议的目标之一是在知识中填补这一空白。我们的初步研究表明，鼠和人LG MECs表达催产素受体（OXTR）和响应催产素模拟的收缩。此外，我们表明，长期发炎的LG中的MEC是萎缩的，收缩蛋白SMA和CALPONIN的下调以及这些腺体的OXTR和MECS与氧气刺激的响应没有收缩。我们先前报道说，白介素-1（IL-1）抑制了导致DED的LG有效神经释放神经递质。我们还报道了应力激活的C-JUN N末端激酶（JNK）和金属蛋白酶2（MMP2）在慢性发炎的LG中激活，并且在DED动物模型中，抑制任一途径的LG分泌和泪液输出。大量研究表明，肌肉时机的神经化导致组织萎缩和通过泛素/蛋白酶体途径的肌肉收缩蛋白降解。基于这些发现，我们假设在慢性DED中，促炎细胞因子抑制神经递质从LG有效神经释放出产生变性的组织，并且它们会触发OXTR和MEC肌肌纤维丝蛋白的降解。这种降解转化为MEC的合同性丧失，从而进一步加剧了神经输入损失对LG分泌单位的影响。我们进一步假设JNK，MMP2和泛素/蛋白酶体途径介导促炎细胞因子对MEC功能的影响。我们将同时使用体外（分类的MEC细胞）和DED的动物模型来研究促炎细胞因子如何干扰LG MEC的氧收缩。我们将使用无偏的RNA-seq和定量全局蛋白质组学技术来识别长期发炎的MEC中改变的新途径。这些研究完成后，我们将确立MEC的作用，MEC，LG中的重要且知识的细胞，以及在缺乏水的发病机理中的氧气到CIN信号系统，并确定了潜在的新型治疗靶标。