The effect of artesunate on inflammatory responses to severe pneumonia by regulating MIF in rats

Objective To study the effect of artesunate on inflammatory responses to severe pneumonia by regulating macrophage migration inhibitory factor (MIF) in rats. Methods Total of 100 SD by random(random number) assigned, 20 rats were control group, 80 SD rats with severe pneumonia were caused by Klebsiella pneumoniae, 60 SD rats were treated with different concentrations(20, 40, 80 mk/kg) of artesunate after modeling. The pathological changes of lung tissue, the level of MIF myeloperoxidase activity and inflammatory cell infiltration in lung tissue of rats were evaluated. Results After treatment with artesunate, the severity of inflammation was significantly alleviated in rats with severe pneumonia evidenced by decrease in myeloperoxidase activity [severe pneumonia: (17.5 ± 1.5)vs.treatment group: (7.5 ± 2.0) ]and reduction in inflammatory cell infiltration (severe pneumonia: 27×106vs. treatment group: 12.5×106). Similarly, the artesunate also reduced the production of inflammatory cytokines significantly in bronchoalveolar lavage fluid (IL-1 in severe pneumonia group: (1 100 ± 50) pg/ml vs. treatment group: (400 ± 60)pg/ml; IL-6 in severe pneumonia group: (700 ± 30)pg/ml vs.treatment group: ( 200 ± 40)pg/ml; IL-10 in severe pneumonia group: (500 ± 70)pg/ml vs. treatment group: (200 ± 40)pg/ml; TNF-αin severe pneumonia group: (500 ± 80)pg/ml vs.treatment group: (150 ± 50)pg/ml. In addition, artesunate inhibited the level and production of MIF, thus inhibiting the inflammatory responses mediated by MIF. Conclusions Artesunate had a protective effect on pneumonia caused by Klebsiella pneumoniae in rats via inhibiting the inflammation responses mediated by MIF. This study provided a molecular basis for newly developed drugs applied to the treatment of pneumonia caused by Klebsiella pneumoniae in rats. Key words: Artesunate; Severe pneumonia; Macrophage inhibitory factor; Interleukin; Inflammatory responses; Molecular mechanism; Immunoregulation; Animal model