The primary purpose of this study was to demonstrate the preventive effects of imatinib (IMA) on lipopolysaccharide (LPS)-induced inflammation in a mouse model of acute lung injury (ALI) and human umbilical vascular endothelial cells. LPS stimulation for 24h induced ALI and cell inflammation. The pathological results of the lungs were evaluated using the wet/dry weight ratio, pulmonary vascular permeability measurements, and myeloperoxidase immunohistochemistry. The expression of pro-inflammatory mediators was analyzed using RT-PCR and enzyme-linked immunosorbent assay. Protein levels were analyzed using western blotting. The structure of cell junctions was detected using immunofluorescence. IMA improved LPS-induced pulmonary pathological damage and reduced the lung wet/dry weight ratio and myeloperoxidase expression in the lung tissue. IMA decreased bronchoalveolar lavage fluid inflammatory cell count and the release of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and monocyte chemotactic protein 1 (MCP-1) in the blood. Pretreatment of human umbilical vascular endothelial cells with IMA significantly attenuated LPS-induced actin stress fiber formation and vascular endothelial-cadherin disruption. In addition, IMA downregulated the mRNA abundances of vascular cell adhesion molecule 1, intercellular adhesion molecule 1, IL-1β, IL-6, and tumor necrosis factor-α(TNF-α) expression. The phosphorylation of p65, nuclear factor-kappa B inhibitor alpha (IκBα), p38, extracellular signal-regulated kinase, and Jun N-terminal kinase induced by LPS were attenuated after IMA treatment in vivo and in vitro. IMA modulates the nuclear factor-kappa B and mitogen-activated protein kinase signaling pathways and the production of pro-inflammatory cytokines to prevent cellular damage due to LPS infection. These results indicate that IMA may be a potential modulator of LPS-induced ALI.
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