【作者】 宁娜；

【导师】 甄宏韬；

【作者基本信息】 华中科技大学 ， 耳鼻咽喉头颈外科， 2013， 硕士

【摘要】 背景：变应性鼻炎是IgE介导的速发型超敏反应，与许多黏膜炎症性疾病如哮喘、鼻窦炎、变应性结膜炎等相关。变应性鼻炎的发病率逐年增加。槲皮素属于黄酮类，常在洋葱、苹果、红酒、绿茶中发现。研究证实槲皮素在气道中具有各种生物学活性。本实验的研究目的是探讨槲皮素治疗变应性鼻炎模型小鼠的效果及其机制。方法：将雄性BALB/c小鼠随机分成五组：对照组（Ctr组），以生理盐水处理小鼠；变应性鼻炎模型组（AR组），以卵清蛋白致敏、激发小鼠；氯雷他定组（Lora组），低浓度槲皮素组（Low组）和高浓度槲皮素组(High组)，均用卵清蛋白致敏、激发小鼠，分别以氯雷他定、低浓度槲皮素（50mg/kg）、高浓度槲皮素（100mg/kg）对小鼠行灌胃。最后一次灌胃后，观察各组小鼠抓鼻及打喷嚏的情况。通过ELISA方法检测血清中OVA-IgE及鼻腔灌洗液中IL-4、IFN-γ的水平，流式细胞仪计数小鼠脾细胞中CD4+CD25+Foxp3+细胞和CD4+IL-17+细胞。结果：经过槲皮素灌胃后，小鼠打喷嚏、抓鼻的次数较变应性鼻炎组减少，血清中OVA-IgE、鼻腔灌洗液中IL-4水平较变应性鼻炎组降低，而槲皮素对鼻腔灌洗液中IFN-γ作用不明显。槲皮素能调节Treg细胞和Th17细胞的平衡。结论：槲皮素可以通过抑制血清中OVA-IgE及鼻黏膜Th1细胞分泌的IL-4的产生，并调节脾细胞中CD4+CD25+Foxp3+细胞和CD4+IL-17+细胞的比例来抑制过敏性反应。更多还原

【Abstract】 Background: Allergic rhinitis (AR) is caused by IgE-mediated immediatehypersensitivity and ultimately progress as chronic nasal inflammation. Quercetinbelongs to the subgroup of flavonols and is the most often found in onions, apples,grapes, red wine and green tea. This flavonoid confirmed several biological activitiesin the airways. Our study aimed to investigate whether quercetin has treatment effectson nasal symptoms of allergic rhinitis model in mice and the mechanism.Materials and Methods: Male BALB/c mice were divided into five groups randomly:the control group (Ctr group), which received saline; allergic rhinitis group (ARgroup), which were sensitized by administering an intraperitoneal injection ofovalbumin (OVA) and aluminium hydroxide hydrate gel (alum), and challenge wasperformed by instilling OVA into the bilateral nasal cavities; loratadine group (Loragroup), the low concentration of quercetin group (Low group) and the highconcentration of quercetin group (High group), which were both sensitized andchallenged by ovalbumin, and administered loratadine, low concentration of quercetin(50mg/kg) and high concentration of quercetin (100mg/kg) respectively. Nasalrubbing and sneezing were monitored after the last administration. In addition, serumOVA-specific immunoglobulin E (IgE) antibody, and interleukin (IL)-4, Interferon(IFN)-γ in nasal lavage fluid were determined by ELISA kits respectively. SplenicCD4+CD25+Foxp3+regulatory T cells (Tregs) and IL-17cells (Th17) were examinedby flow cytometry to investigate the mechanism involved.Results: A significant inhibition of nasal symptoms-sneezing and nasal rubbing insensitized mice was observed after repeated oral administration of quercetin.Additionally, quercetin alleviated both OVA-specific IgE antibody and IL-4production; however, it had no effect on IFN-γ levels in nasal lavage fluid. Finally,quercetin inhibited the airway inflammation of allergic rhinitis by regulating thebalance between Treg and Th17.Conclusion: These results furtherly indicate that quercetin may be effective in the relief of symptoms of allergic rhinitis through reducing OVA-specific IgE and IL-4levels, and moduating the ratio of spleen CD4+CD25+Foxp3+cells and CD4+IL-17+cells. Therefore, our results demonstrate that the balance of Treg/Th17can also play arole in the pathogenesis of allergic rhinitis.更多还原