Abstrait

Protective effect of new fuzheng chuyi granule on the lung tissue in acute upper respiratory tract infection mice and its mechanisms

Xin Su, Shuang Jiang, Guang Yang, Xiaoyan Gong

This research studied the protective effect of New Fuzheng Chuyi Granule (NFCG) on the lung tissue of mice with acute upper respiratory tract infection (AURI) and its mechanisms. A mouse model of AURI was established by intranasal instillation of Streptococcus pneumoniae, and high-dose (5.28 g/kg), medium-dose (2.64 g/kg) and low-dose (1.23 g/kg) of NFCG were intragastrically given to the mice, respectively, and on the 1^st, 4^th and 7^th day after the administration, lung wet/dry weight ratio and lung index were calculated, pathological changes of the lung tissue and the spleen lymphocyte proliferation were observed, and TNF-α, IL-6, IL-1, IFN-γ, TLR2, TLR4, MyD88, and NF-κB expressions in the lung tissue were detected. The results showed that NFCG could reduce the lung wet/dry weight ratio and the lung index, alleviate the pathological changes in the lung tissue, and increase the spleen lymphocyte proliferation in mice; in addition, NFCG could reduce the expression of several pro-inflammatory factors, including TNF-α, IL- 6, IL-1 and IFN-γ, and TLR2, TLR4, MyD88 and NF-κB proteins. These results suggest that NFCG can protect the lung tissue of mice with AURI, which may be related to its improving the immunity, anti-inflammation and regulation of TLR2/4-MyD88 signaling pathway.