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 TH2/TH1 in mice infected by respiratory syncytial virus

摘要:

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。

Abstract:

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 virus (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-4 (IL-4) and interferon-gamma (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-4 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-4 level and increased the γ-IFN level. The Xuan and Jiang component treatment decreased the IL-4 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-4 levels, worked by Xuan and Jiang components, and increasing γ-IFN levels, worked by Qing component.