定喘汤调整呼吸道合胞病毒感染小鼠T_H2/T_H1免疫失衡

Dingchuantang decoction restores the imbalance of T_H2/T_H1 in mice infected by respiratory syncytial virus

目的该研究观察定喘汤及“宣法”、“降法”、“清法”三组分解剂对呼吸道合胞病毒(RSV)感染小鼠肺组织RSV量及肺泡灌洗液(BALF)中TH2细胞因子IL4和TH1细胞因子γIFN的含量的影响,探讨定喘汤的作用机制。方法120只小鼠随机分正常组,病毒组,定喘汤组,宣法组,降法组,清法组6组(均n=20)。后5组小鼠接种RSV,制成小鼠RSV感染模型;各治疗组分别给予定喘汤及宣法、降法、清法3种分解剂灌胃给药。逆转录聚合酶链式反应(RT-PCR)检测小鼠肺组织RSV的含量,酶联免疫吸附试验(ELISA)法检测小鼠肺泡灌洗液(BALF)中IL4、γIFN的含量。结果RT-PCR结果显示定喘汤组、清法组和宣法组RSV的含量较病毒组显著降低,而降法组和病毒组比较差异无显著性。RSV感染后,BALF中IL4增高而γIFN降低,导致IL4/γIFN显著增高。定喘汤治疗能减少BALF中IL4含量,增加γIFN含量,恢复IL4/γIFN平衡。宣法组、降法组可减少IL4含量,但对γIFN没有明显影响;清法组可增加γIFN含量,对IL4无明显影响。结论定喘汤具有抗RSV作用,主要表现在清法组和宣法组,而降法组作用不明显;定喘汤可调节TH2/TH1免疫失衡,主要表现在宣法组、降法组降低IL4,清法组提高γIFN。

Objective Dingchuantang is a traditional Chinese medicine decoction which has the Qing, Xuan and Jiang components which have the ability to dispel （ Xuan）, depress （Jiang） and heat clear or febrigugal （Qing）. It has been used for asthma and respiratory syncytial vires （ RSV ） infection. However, the therapeutic mechanisms of the decoction have not been identified. To understand the mechanism of the anti-RSV property of Dingchuantang, this study investigated the effects of Dingchuantang and its three components on the levels of interleukin-d （ IL-d ） and interferongamma （γ-IFN） in mice infected by RSV. Methods One hundred and twenty mice were randomly assigned into Normal, Infected, Dingchuantang-treated, Qing component-treated, Xuan component-treated and Jiang component-treated groups （n = 20 each）. The RSV infection model was prepared in the rats from the last 5 groups. The 4 treatment groups were administered with Dingchuantang, Qing component, Xuan component and Jiang component by gastric lavage respectively 2 hrs after RSV innoculation. The contents of RSV in the lungs were tested by reverse transcription polymerase chain reaction （RT-PCR）. The levels of IL-d and γ-IFN in broncho-alveolar lavage fluid （BALF） were measured by enzyme linked immunosorbent assay （ELISA）. Results The contents of RSV of lungs in the Dingchuantang-treated group, and Qing and Xuan component-treated groups were significantly lower than those in the untreated Infected group. There was no significant difference between the Jiang component-treated and the Infected group. Dingchuantang treatment decreased the IL-d level and increased the γ-IFN level. The Xuan and Jiang component treatment decreased the IL-d level but had no effect on the γ-IFN level, while the Qing component-treatment increased the γ-IFN level but had no effect on the IL-4 level. Conclusions Dingchuantang can inhibit RSV reproduction and this effect works by Qing and Xuan components. Dingchuantang can also restore the imbalance TH2/TH1 by depressing IL-d levels, worked by Xuan and Jiang components, and increasing γ-IFN levels, worked by Qing component.