Efficacy and mechanism of Lianhua Qingwen Capsules(LHQW) on chemotaxis of macrophages in acute lung injury (ALI) animal model

Abstract

This paper was mainly to discuss the potential role and mechanism of Lianhua Qingwen Capsules(LHQW) in inhibiting pathological inflammation in the model of acute lung injury caused by bacterial infection. For in vitro study, the mRNA expression of MCP-1 in RAW264.7 cells and THP-1 cells, the content of MCP-1 in cell supernatant, as well as the effect of LHQW on chemotaxis of macrophages were detected. For in vivo study, mice were randomly divided into 7 groups, including normal group, model group(LPS 5 mg·kg~(-1)), LHQW 300, 600 and 1 200 mg·kg~(-1)(low, middle and high dose) groups, dexamethasone 5 mg·kg~(-1) group and penicillin-streptomycin group. Then, the anal temperature was detected two hours later. Dry weight and wet weight of lung tissues in mice were determined; TNF-α and MCP-1 levels in alveolar lavage fluid and MCP-1 in serum were detected. In addition, the infiltration of alveolar macrophages was also observed and the infiltration count of alveolar macrophages was measured by CCK-8 method. HE staining was also used to observe the inflammatory infiltration of lung tissues in mice. Both of the in vitro and in vivo data consistently have confirmed that: by down-regulating the expression of MCP-1, LHWQ could efficiently decrease the chemotaxis of monocytes toward the pulmonary infection foci, thus blocking the disease development in ALI animal model.