班布特罗对哮喘豚鼠淋巴细胞核因子-κB 表达的影响

目的:探讨β2-受体激动剂班布特罗(bambuterol)对哮喘豚鼠支气管肺泡灌洗液(BALF) 淋巴细胞核因子-κB (NF-κB) 表达的影响。方法:用卵白蛋白(ovalbumin, OA) 建立豚鼠哮喘模型, BALF 分离淋巴细胞, 采用免疫组化染色方法观察淋巴细胞NF-κB 表达, 酶联免疫吸附(ELISA) 法测定淋巴细胞胞浆IκB 含量及BALF 中白细胞介素-10(IL-10) 水平。结果:与模型组相比, 班布特罗可显著增加BALF 中IL-10 水平及淋巴细胞胞浆IκB 含量(P <0.05), 降低NF-κB 胞核阳性细胞百分比(P <0.05), 而且这一作用可被β2-受体阻断剂普奈洛尔拮抗;但IκB 含量及IL-10 水平仍低于正常对照组(P <0.05), NF-κB 胞核阳性细胞百分比仍高于正常对照组(P <0.05) 。Pearson 相关分析显示NF-κB 与IL-10 之间呈明显负相关关系(r =-0.570, P <0.01) 。结论:班布特罗通过抑制IκB 降解和增加IL-10 水平, 从而抑制淋巴细胞NF-κB 表达, 这可能是其抑制哮喘气道慢性炎症的机制之一。

Effects of bambuterol on expression of nuclear factor-kappa B of lymphocytes in asthmatic guinea pigs

AIM: To investigate the effects of bambuterol (the agonist of beta2-adrenergic receptor) on expression of nuclear factor-kappa B (NF-κB) of lymphocytes in bronchoalveolar lavage fluid (BALF) of asthmatic guinea pigs.METHODS: Experimental asthma model of guinea pigs was induced by ovalbumin in vivo, lymphocytes in BALF were separated, the expression of NF-κB of lymphocytes was observed by immunohistochemical staining, and inhibitory kappa B (IκB) in lymphocytes and interleukin(IL)-10 in BALF were detected by enzyme-linked immunoadsorbent assay (ELISA).RESULTS: Compared with model group, bambuterol could increase IκB in lymphocytes and IL-10 in BALF and decrease the percentage of nuclear NF-κB⁺ cells significantly (P <0.05).These effects could be abolished completely by pretreatment with propranolol.While compared with normal control group, IκB and IL-10 of therapeutic group were lower and the percentage of nuclear NF-κB⁺ cells was also higher.Furthermore, there was a significantly negative correlation between the percentage of nuclear NF-κB⁺ cells and the concentration of IL-10 (r =-0.570, P <0.01).CONCLUSION: Increasing the levels of IκB and IL-10 and inhibiting expression of NF-κB subsequently may be one of important mechanisms of bambuterol on airway inf lammation of asthma.