【摘要】 目的观察γ-分泌酶抑制剂(3,5-二氟苯乙酰基)-L-丙氨酰基-L-2-苯基甘氨酸叔丁酯[(3,5-difluorophenylacetyl)-L-alanyl-L-2-phenylglycine tert-butyl ester,DAPT]对过敏性鼻炎小鼠模型的影响并分析其作用机制,为过敏性鼻炎寻求新的药物治疗提供理论基础。方法 32只无特定病原体(specific pathogen free,SPF)级BALB/c小鼠随机等量分成4组,标准喂养1周后,于第1、5、9、12天对小鼠进行处理:对照组给予标准的磷酸盐缓冲溶液(phosphate buffer saline,PBS) 0. 4 ml腹腔注射,模型组给予卵清蛋白(ovalbumin,OVA)混悬液0. 4 ml腹腔注射;并于第13～20天对不同组小鼠进行滴鼻处理:对照组小鼠给予标准的PBS溶液滴鼻,模型组用含10%OVA的PBS溶液滴鼻,均10μl/侧每天;二甲基亚砜(dimethyl sulfoxide,DMSO)组和DAPT组小鼠的给药时间、剂量及用药均同模型组,并于每次给药前30 min腹腔分别注射DMSO和DAPT混悬液0. 4 ml。四组小鼠均在最后一次滴鼻后12 h时处死并收集标本。通过症状观察、HE染色、酶联免疫吸附等观察DAPT对过敏性鼻炎小鼠的影响并分析其作用机制。结果 DAPT组小鼠临床症状评分(2. 18±0. 56)与对照组接近(1. 75±0. 23),均明显低于模型组(6. 89±1. 2),差异有统计学意义(P<0. 05)。与模型组(13. 78±3. 06、7. 89±1. 38)和DOSM组(13. 26±0. 21、7. 17±0. 86)相比,DAPT组小鼠挠比次数、打喷嚏次数明显减少,分别为5. 57±0. 53、3. 25±0. 86,差异有统计学意义(P<0. 05)。模型组小鼠鼻腔黏膜中大量炎性细胞浸润,腺体增生明显,而DAPT组小鼠鼻腔黏膜已开始修复,与模型组相比,炎性细胞明显减少,腺体增生和间质水肿也明显减轻。DAPT组小鼠IgE的表达量(6. 741 2±0. 52)、IL-4的表达量(11. 279 5±0. 49)明显低于模型组(12. 132 7±0. 5、16. 563 4±0. 64)和DMSO组(12. 073 8±1. 30、16. 262 1±0. 50. 29),差异均有统计学意义(P<0. 05),与对照组表达量相比(6. 007 7±0. 91、10. 5729±1. 76)差异无统计学意义(P>0. 05);而DAPT组小鼠IFN-γ的表达量(9. 965 7±1. 68)则明显高于模型组(2. 557 0±1. 95)和DMSO组(1. 904 5±0. 48),差异有统计学意义(P<0. 05),与对照组表达量相比(11. 650 8±2. 36)差异无统计学意义(P>0. 05)。结论γ-分泌酶抑制剂DAPT能有效缓解过敏性鼻炎小鼠的过敏症状,改善鼻黏膜病理损伤和降低血清特异性抗体IgE的浓度; DAPT有可能通过调节Th1/Th2的平衡,促进Th0细胞向Th1方向分化,影响过敏性鼻炎的发生发展,对过敏性鼻炎有潜在的治疗价值。更多还原

【Abstract】 Objective To investigate the effect and mechanism of γ-secretase inhibitor DAPT on mouse model of allergic rhinitis,providing theoretical basis for new drug treatment of allergic rhinitis. Methods Thirty-two SPF BALB/c mice were randomly divided into 4 groups. After one week feeding in SPF laboratory,the mice were treated on the 1 st,5 th,9 th,and 12 th day. The mice in control group were injected intraperitoneally with standard PBS solution 0. 4 ml at above time points. The mice in model group were injected intraperitoneally with ovalbumin( OVA) suspension 0. 4 ml. On the 13 th to 20 th day,the mice in the control group were treated with standard PBS solution nasal drops 10 μl each side everyday,and the model group was given PBS solution nasal drops containing 10% OVA 10 μl once per day. The administration time,dose,and treatment for DMSO group and DAPT group were as the same as those for model group. DMSO or DAPT suspension 0. 4 ml was injected intraperitoneally 30 min before each injection of OVA. The mice in all four groups were killed 12 hours after the last nasal drips and the specimens were collected. The effect of DAPT on allergic inflammation in mice was evaluated by symptom observation,HE staining and enzyme-linked immunosorbent assay( Elisa),while its mechanism was analyzed. Results The clinical symptom score of DAPT group( 2. 18 ± 0. 56) was close to that of the control group( 1. 75 ± 0. 23),which was significantly lower than that of the model group( 6. 89±1. 2). Compared with the model group( 13. 78±3. 06,7. 89±1. 38) and DOSM group( 13. 26±0. 21)( 7. 17±0. 86),the number of deflection ratio and sneezing in DAPT group were significantly lower than those in model group and DAPT group,which were( 5. 57±0. 53) and( 3. 25±0. 86),respectively,with significant difference( P<0. 05). In the model group,a large number of inflammatory cells infiltrated and the hyperplasia of the gland was obvious,while the nasal mucosa of the DAPT group had begun to repair. Compared with the model group,the inflammatory cells were significantly reduced,and the hyperplasia of the gland and the edema of the stroma were also significantly alleviated. The expression of Ig-E and IL-4 in DAPT group( 6. 741 2 ±0. 52,11. 279 5±0. 49) was significantly lower than that in model group( 12. 132 7± 0. 5,16. 563 4±0. 64)and DMSO group( 12. 073 8±0. 130,16. 262 1±0. 502 9). There was significant difference between them( P<0. 05),but there was no significant difference than control group( 6. 007 7 ± 0. 91,10. 5729 ± 1. 76)( P >0. 05). Meamtime the expression of IFN-γin DAPT group( 9. 9657±1. 68) was significantly higher than that in model group( 2. 557 0±1. 95) and DMSO group( 1. 904 5 ± 0. 48)( P < 0. 05). but it’s smile to the control group( 11. 650 8±2. 36)( P>0. 05). Conclusions γ-Secretase inhibitor DAPT can effectively achieve relief of allergic rhinitis symptoms,alleviate the pathological injury of nasal mucosa and decrease the concentration of serum specific Ig E antibody in mice model. DAPT may affect the occurrence and development of allergic rhinitis,based on its influence on the regulation of Th1/Th2 equilibrium,which promoted the differentiation of Th0 to Th1. DAPT was shown potential therapeutic value for allergic rhinitis.更多还原