Mucin sialylation drives epithelial cell senescence and severe asthma

粘蛋白唾液酸化导致上皮细胞衰老和严重哮喘

• 批准号: 10206266
• 负责人: Richard Charles Boucher
• 金额: $ 69万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10206266
• 关键词: Agonist; Asthma; Biological; Biological Markers; CCND1 gene; Carbohydrates; Cell Aging; Cell Communication; Cell Count; Cell Culture Techniques; Cell Differentiation process; Cell surface; Cells; Chronic; Data; Disease; ERBB2 gene; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cell Proliferation; Epithelial Cells; Evolution; Family; Family member; Functional disorder; Galactosides; Gene Expression; Genes; Glutathione; Glutathione Disulfide; Goblet Cells; Human; Human Biology; Hyperplasia; In Vitro; Inflammation; Interleukin-13; Link; Lung; Measures; Metabolic; Metabolic dysfunction; Metabolic stress; Metabolism; Mitochondria; Mucins; Mus; Oxidative Stress; Pathway interactions; Phenotype; Post-Translational Protein Processing; Process; Proteins; Proto-Oncogene Proteins c-akt; Publishing; Pyroglyphidae; Reporting; Role; Severities; Severity of illness; Sialyltransferases; Sputum; Stimulus; TNF gene; Testing; Time; Tissues; Transgenic Mice; Up-Regulation; airway epithelium; asthma exacerbation; asthmatic; asthmatic airway; asthmatic patient; cell type; driving force; epithelial wound; extracellular; glycosylation; improved; in vivo; mTOR inhibition; mouse model; new therapeutic target; novel; oxidation; particle; protein expression; receptor; senescence; sialylation; wound healing

This application explores the paradigm shifting hypothesis that post-translational modification (sialylation) of a cell surface (tethered) mucin, MUC4, drives terminal differentiation and senescence of airway epithelial cells (AECs) through inhibition of epidermal growth factor receptor (EGFR) family pathways, worsening epithelial wound repair and asthma severity. Our proposed studies will be the first to specifically test tethered mucins and their post-translational N-glycosylation/sialylation for a role in AEC terminal differentiation and senescence. Our published data (Zhou et al) demonstrate that sialylation of the tethered mucin, MUC4β, i.e., MUC4α βSA, controls goblet cell terminal differentiation as a function of β-galactoside α2,6-sialyltransferase-1 (ST6GAL1) activity. Both ST6GAL1 and MUC4β critically lower AEC proliferative capacity, with additional published data (Inoue et al) linking diminished AEC proliferation to abnormal wound repair in vitro. Reduced AEC proliferative capacity may reflect reduced activation of the EGFR family member, ErbB2, a known receptor for MUC4β. New data confirm that elevations in MUC4 and ST6GAL1 are present in severe exacerbation-prone asthma and in house dust mite challenged mice. Elevations in both biologically associate with low intracellular glutathione (GSH) to oxidized glutathione (GSSG) ratios (oxidative stress) and lower mitochondrial and senescence gene expression. Parallel in vitro AEC data show T2 inflammation/IL-13 alters intracellular metabolism and mitochondria, decreases GSH/GSSG, and further decreases wound repair. Yet, the overall impact of MUC4β and/or its sialylation to epithelial cell phenotypes, cell senescence, and the mechanisms by which these changes contribute to severe asthma are unclear. The studies proposed here will comprehensively evaluate the intersection of mucins, mucin sialylation, and senescence pathway(s), while robustly testing their functional importance using primary human AEC cell cultures and transgenic mouse models. The three proposed aims will: 1) elucidate the mechanistic and functional impact of MUC4β and MUC4βSA on AEC terminal differentiation, senescence and wound repair in vitro, 2) test the functional impact of Muc4βSA-AEC interactions on mucin secretion, goblet cell hyperplasia/terminal differentiation, senescence, and wound repair in an asthma mouse model and 3) define the relationship of MUC4βSA to senescence and AEC phenotypes in human asthma patients. These concurrent aims will iteratively develop data that link mucins, their sialylation and fundamental senescence-related epithelial processes to identify highly novel targets for treatment of severe asthma.

该应用程序探讨了范式转换假设，即翻译后修饰（唾液酸化） 细胞表面（束缚）粘蛋白 MUC4 驱动气道上皮细胞的终末分化和衰老 （AEC）通过抑制表皮生长因子受体（EGFR）家族途径，使上皮细胞恶化 伤口修复和哮喘严重程度。我们提出的研究将是第一个专门测试束缚粘蛋白和 它们的翻译后 N-糖基化/唾液酸化在 AEC 终末分化和衰老中发挥作用。我们的 已发表的数据（Zhou 等人）表明，拴系粘蛋白 MUC4β（即 MUC4α βSA）的唾液酸化可以控制 杯状细胞终末分化作为 β-半乳糖苷 α2,6-唾液酸转移酶-1 (ST6GAL1) 活性的函数。 ST6GAL1 和 MUC4β 均严重降低 AEC 增殖能力，并有其他已发表的数据（Inoue 等人） al) 将 AEC 增殖减少与体外伤口修复异常联系起来。 AEC增殖能力降低 可能反映了 EGFR 家族成员 ErbB2（一种已知的 MUC4β 受体）的激活减少。新数据 确认 MUC4 和 ST6GAL1 的升高存在于严重易发作哮喘和室内 尘螨挑战小鼠。两者的升高在生物学上都与低细胞内谷胱甘肽 (GSH) 相关 氧化型谷胱甘肽 (GSSG) 比率（氧化应激）以及较低的线粒体和衰老基因表达。 平行体外 AEC 数据显示 T2 炎症/IL-13 改变细胞内代谢和线粒体， 降低 GSH/GSSG，并进一步降低伤口修复。然而，MUC4β 和/或其 唾液酸化对上皮细胞表型、细胞衰老以及这些变化的机制 至严重哮喘尚不清楚。这里提出的研究将综合评估 粘蛋白、粘蛋白唾液酸化和衰老途径，同时使用以下方法强有力地测试它们的功能重要性 原代人 AEC 细胞培养物和转基因小鼠模型。拟议的三个目标将：1）阐明 MUC4β和MUC4βSA对AEC终末分化、衰老和功能的影响 体外伤口修复，2) 测试 Muc4βSA-AEC 相互作用对粘蛋白分泌、杯状细胞的功能影响 哮喘小鼠模型中的增生/终末分化、衰老和伤口修复，3) 定义 MUC4βSA 与人类哮喘患者衰老和 AEC 表型的关系。这些共同目标 将迭代开发将粘蛋白、其唾液酸化和基本衰老相关上皮细胞联系起来的数据 确定治疗严重哮喘的高度新颖的靶标的过程。