Therapeutic Effect and Mechanism of Chaige Qinlian Tang on Young Mouse MRSA Pneumonia Model / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the therapeutic effect and mechanism of Chaige Qinlian Tang on pneumonia in young mice. Method:The pneumonia model was duplicated by slowly dripping Staphylococcus aureus into the nasal cavity of mice.After successful modeling, the mice were randomly divided into model group, clindamycin group, and high and low-dose Chaige Qinlian Tang groups, with sham operation group as negative control group.The rats were given 200 mg·kg-1 high-dose Chaige Qinlian Tang, 100 mg·kg-1 low-dose Chaige Qinlian Tang and 120 mg·kg-1 clindamycin.The mice were observed every day.Colonies were counted in the lungs of each group five days later.The expression levels of interleukin(IL)-16, tumor necrosis factor (TNF)-α in lung lavage fluid of each group were determined by enzyme linked immunosorbent assay (ELISA). Real-time fluorescent quantitative polymerase chain reaction (Real-time PCR) and Western blot were used to measure the expression levels of IL-16, TNF-α in lung lavage fluid of each group.The expressions of tumor necrosis factor receptor (TNFR) 1, Caspase-3 and Caspase-7 in lung and the pathological changes of lung were observed. Result:Compared with the sham operation group, the respiratory state and the activity state of the model mice were worse, and the survival rate was higher in the high-dose Chaige Qinlian Tang group.Compared with the sham operation group, the pulmonary colony counts in the model group and treatment groups were increased, compared with the model group, the lung colony counts in clindamycin group and high-dose Chaige Qinlian Tang group were improved significantly (P<0.05, P<0.01). Compared with the control group, the expression levels of IL-16, TNF-α, TNFR1, Caspase-3, Caspase-7 mRNA and protein in the lung of model group and treatment groups were significantly increased (P<0.01). Compared with model group, the expression levels of IL-16, TNF-α and TNFR1, Caspase-3, Caspase-7 in the lung of clindamycin group and high and low-dose Chaige Qinlian Tang groups were significantly increased (P<0.01). The expression levels of protein and mRNA were significantly decreased (P<0.05, P<0.01), and the pathological changes of lung were improved, especially in clindamycin group and high-dose Chaige Qinlian Tang group. Conclusion:Chaige Qinlian Tang has a certain therapeutic effect on Staphylococcus aureus pneumonia in young mice.This effect may be related to regulating TNFR1, Caspase-3 and Caspase-7 pathways, reducing the secretion of IL-16 and TNF-alpha, and enhancing the clearance of staphylococcus aureus.