甘草酸二铵对支气管哮喘辅助T细胞1/2偏移调节作用的实验研究

Regulatory effect of diammonium glycyrrhizinate on Th1/Th2 deviation in bronchial asthma:experiment with rats

目的探讨甘草酸二铵(甘利欣)对支气管哮喘辅助 T 细胞(Th)1/Th2偏移的调节作用。方法将大鼠随机分为正常对照组、哮喘模型组、甘利欣用药组及地塞米松用药组,通过描记呼吸曲线、肺组织病理切片及 ELISA 法检测血清 IgE 水平来鉴定模型成立,用 L_(929)-VSV 系统同时设标准品检测干扰素-γ(IFN-γ),ELISA 法检测白细胞介素-4(IL-4)水平。结果哮喘模型组大鼠呼吸曲线幅值(0.14±0.01)mV,频率增快,肺组织病理切片可见支气管黏膜下层大量炎性细胞浸润、杯状细胞增生、支气管黏膜断裂、黏膜下肌层增厚,且诱生上清中 IL-4水平为(305±36)pg,IFN-γ水平为(1.6±0.4)U;甘利欣用药组 IL-4水平(168±10)pg、IFN-γ(18.7±5.5)U;地塞米松用药组 IL-4(213±47)pg,IFN-γ(2.1±0.3)U。结论哮喘模型大鼠存在着 Th1/Th2偏移,甘利欣可使 IFN-γ增高可能具有促进 Th1极化的作用。

Objective To study the regulatory effect of diammonium glycyrrhizinate （GL） on the Th1/Th2 deviation in bronchial asthma. Methods Thirty Wistar rats were injected intraperitoneally with antigen solution including ovalbumin （ OVA）, inactivated pertussis vaccine, and aluminum hydroxide for the purpose of sensitization. Fourteen days later OVA was spraied 20 min everyday for consecutive 5 days to evoke sensitization, thus models of asthma were established. Then the 30 rats were randomly divided into 3 equal groups ： asthma model group, model ＋ GL group , and model ＋ DXM group. Another 10 rats were used as control group. All rats underwent tracheal intubation to perform the breathing curves. By the end of the experiment the rats were killed with their lungs taken out to undergo pathological examination. Suspension of splenocytes was prepared, the level of interferon （IFN）-γ, a cytokine mainly secreted by Tbl cells, was detected by L929-VSV system, and the IL-4 level was detected by ELISA. Results The amplitude of the breathing curve of the GL group was similar to that of the DXM group, both significantly lower than that of the model group [ （0. 139 ±0. 011） mV, both P 〈 0.01 ] and higher than that of the control group. The respiratory rates of all groups became faster than normal. Pathology showed infiltration of inflammatory ceils and proliferation of cup-shaped cells in the pneumonic tissues in the model group, and such damages were much slighter in the GL and DXM groups. The IFN-γ level of the model group was （ 1.6 ±0.4 ） U, significantly lower than that of the control group [ （ 3.7 ± 1.0） U, P 〈 0.05 ]. The IFN-γ level of the GL group was （ 18.7 ±5.5） U, significantly higher than those of the DXM group [ （2. 1 ±0.3） U], model group and control group （ all P 〈 0.01 ）. The IL-4 level of the model group was （305 ± 36） pg, significantly higher than those of the GL group [ （ 168 ± 10） pg, P 〈0.01 ], DXM group [ （213 ±47） pg], and control group [ （54 ±6） pg, P 〈 0.01 ], however, there was no significant difference between the GL and DXM groups. Conclusion GL increases the IFN-γ level and decreases the IL-4 level, thus promoting the polarization of Thl cells, regulating the Tb1/Th2 deviation, and alleviating asthma.