芒果苷调控慢性支气管炎症及炎症细胞活化关键基因与蛋白表达的研究

Mangiferin is the major effective ingredient of Mangifera indica Linn. Leave. Mangiferin was reported to have a noteworthy pharmacological effect on various acute or chronic inflammations. The present study is based on always research results from our research team. This study aims to investigate the regulation of mangiferin on chronic bronchitis and its cellular and molecular pharmacology basis. As a research object, a rat model with chronic bronchitis due to smoking plus lipopolysaccharide endotracheal perfusion will be adopted in the research. The flow cytometry, fluorescent in situ histology and transmission electron microscopy will be adopted. With them, blood inflammatory cell amounting with its subgroups, inflammatory mediators and the bronchial pathological form will be researched to explain the regulation of mangiferin on the airway inflammation in rats with chronic bronchitis. The lipopolysaccharide or inflammatory cytokines will be used to establish activated macrophage, T lymphocyte and neutrophil models in vitro. The real-time quantitative fluorescence PCR, flow cytometry and laser scanning confocal microscopy analysis will be excutived. Using these cell models and technologic methods, effects of mangiferin on inflammatory cell activation, key inflammation gene and proteins will be investigated to find the regulatory acts on chronic bronchitis by mangiferin in a multi-target way, and explain its cellular and molecular pharmacology basis. Therefore, we hope that some research evidences from this study should be discovered. These findings could be employed to develop a new drug with safe and effective anti-inflammation from mangiferin.

芒果苷是芒果叶中的主要有效成分，对多种急慢性炎症具有较好抗炎作用。基于本研究团队既往的研究成果，本研究旨在探讨芒果苷对慢性支气管炎症的调控作用及其细胞与分子药理学基础。本研究以烟熏并气管内灌注脂多糖诱导的慢性支气管炎大鼠模型为研究对象，应用流式细胞术、原位荧光标记、透射电子显微镜等技术手段，观察芒果苷干预对循环中的白细胞数量、亚群与炎症介质、支气管病理形态的影响，研究芒果苷对慢性支气管炎大鼠呼吸道炎症的调控效应；基于体外脂多糖或炎症细胞因子刺激建立活化的单核-巨噬细胞、T淋巴细胞、中性粒细胞药理研究模型，以实时荧光定量PCR、流式细胞术、激光扫描共聚焦显微分析等方法，观察芒果苷干预对调控炎症细胞活化、活化过程中的关键基因与蛋白表达的影响，研究芒果苷多靶点调控慢性支气管炎症的细胞与分子药理学基础。本研究将为以芒果苷为候选化合物开发能够安全、有效地治疗慢性支气管炎的新型抗炎药物提供实验证据。

本研究旨在探讨芒果苷对烟熏诱导的慢性支气管炎大鼠气道炎症的抑制作用，以及芒果苷对体外激活的单核-巨噬细胞、T淋巴细胞致炎活性的调控作用。研究结果显示，芒果苷可显著减轻香烟烟熏引起的实验性慢性支气管炎大鼠的细支气管炎症，此保护作用可能与以下机制有关：负性调控单核细胞核转录因子P65 [NF-κB (P65)]、核转录因子κB抑制因子α (IκBα) 的表达，拮抗肺组织超氧化物歧化酶3 (SOD3)表达下调，下调CD4+ T淋巴细胞比例并减少淋巴因子白细胞介素-2 (IL-2)、白细胞介素-4 (IL-4)的产生。在体外研究中，100与200 μmol/L的芒果苷显著抑制人THP-1单核细胞循经典激活途径诱导分化为致炎的M1型巨噬细胞，且芒果苷抑制细胞内干扰素调节因子5 (IRF5)表达与此调控效应密切相关。100或200 μmol/L的芒果苷与乙酰胆碱 (ACh) (5μmol/L)联合干预显著抑制人Jurkat淋巴细胞被植物血凝素 (PHA) 刺激而活化，但芒果苷独立应用无效，且该作用可被α银环蛇毒素 (α-BTX) 完全阻断，在此过程中细胞表面的α7烟碱型乙酰胆碱受体 (α7-nAChR) 表达并无显著改变，提示芒果苷增强α7-nAChR介导的抗炎作用并非缘于其自身对α7-nAChR的兴奋作用，而是基于α7-nAChR介导的抗炎作用。此外，芒果苷能够增强ACh兴奋α7-nAChR而介导的信号转导和转录活化蛋白3 (STAT3) 磷酸化以及抑制IκBα磷酸化的作用，提示芒果苷增强α7-nAChR介导的抗炎作用与此密切相关。上述的炎症细胞活化抑制作用，100 μmol/L的芒果苷抑制作用均优于200 μmol/L的芒果苷，提示芒果苷并非简单遵循线性的量效曲线发挥该作用。