牛磺酸对支气管哮喘大鼠气道MLCK和血清IL-5表达的影响

Effect of taurine on expression of myosin light chain kinase in airway and interleukin-5 in peripheral blood of bronchial asthma animal model

目的 探讨牛磺酸对支气管哮喘（简称哮喘）大鼠气道肌球蛋白轻链激酶（MLCK）和血清IL-5表达的影响.方法 32只清洁级健康SD大鼠随机等分为正常对照组、哮喘模型组、牛磺酸干预组、地塞米松干预组.以卵蛋白和氢氧化铝混悬液诱发大鼠哮喘模型.牛磺酸干预组和地塞米松干预组于雾化前1h分别给予腹腔注射0.5 g/kg牛磺酸和0.5 mg/kg地塞米松.计数BALF中白细胞总数和嗜酸粒细胞数,采用免疫组织化学法检测大鼠气道MLCK的表达,采用双抗体夹心法检测大鼠血清IL-5的含量.结果 ①与正常对照组比较,哮喘模型组MLCK和IL-5水平均较高（t=4.324,P＜0.05;t=3.984,P＜0.05）;与哮喘模型组比较,牛磺酸干预组MLCK和IL-5水平均较低（￡=3.987,P＜0.05;t=4.375,P＜0.05）;与地塞米松组比较,牛磺酸干预组MLCK和IL-5水平变化不大,差异无统计学意义（t=0.780,P＞0.05;t=0.674,P＞0.05）.②牛磺酸干预组和地塞米松干预组的大鼠哮喘症状较哮喘模型组明显减轻,但牛磺酸干预组没有出现体质量减轻,食欲减退等不良反应.结论 牛磺酸可能具有通过降低哮喘大鼠气道MLCK水平参与气道舒张以及减轻气道炎症的作用.

Objective To investigate the effect of taurine （TAU） on expression of myosin light chain kinase （MLCK）,interleukin-5 （IL-5） and IgE of bronchial asthma （asthma） rats.Methods Thirtytwo male Sprague-Daw （SD） rats were randomly divided into four groups：normal group （n =8）,asthma group （n =8）,TAU group （n =8） and DXM group （n =8）.The rats were sensitized and challenged with ovalhumin （OVA） to establish chronic asthma model.One hour before each airway challenge,the TAU group rats and DXM group rats were respectively administered intraperitoneally with TAU 0.5 g/kg and DXM 0.5 mg/kg.Counted the total number of leukocyte and eosinophil number in bronchoalveodar lavage fluid （BALF）,determined for airway MLCK by immunohistochemistry,determined for IL-5 levels in blood serum by Elisa.Results ① The expression of MLCK and IL-5 in asthma group increased significantly as compared with normal group （t =4.324,P ＜0.05;t =3.984,P ＜0.05）.The expression of MLCK and IL-5 in TAU group decreased significantly as compared with asthma group （t =3.987,P＜0.05;t =4.375,P ＜0.05）.The expression of MLCK and IL-5 in TAU group were not changed significantly as compared with DXM group （t =0.780,P ＞0.05;t =0.674,P ＞0.05）.②The asthmatic symptoms of TAU group rats and DEX group rats were significantly reduced as compared with asthma group,but the TAU group rats did not lose weight and appetite.Conclusions Taurine could decrease the level of MLCK in the airway in asthma rats to relax airway and reduce airway inflammation.