Objective  To study prevention and treatment effect of Gentiana rhodantha (GR) on Streptococcus pneumoniae (Sp) pneumonia in mice.

  Methods  Thirty clean Kunming mice were randomly divided into 3 groups (10 in each group): a control, a model, and a GR group. Mouse Sp pneumonia model was established with intranasal instillation of bacteria solution. Mice in GR group were administered with GR decoction by intragastric gavage. Eyeball blood samples of all the mice were collected after 10% chloral hydrate anesthesia when there were eye closure and tachypnea in Sp infected mice. Serum levels of C-reaction protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), and interleukin-8 (IL-8) were detected with enzyme-linked immunosorbent assay; pathological changes of lung tissues were observed under light microscope.

  Results  Significantly increased CRP (27.28 ± 7.44 ug/ml, 20.17 ± 3.91 ug/ml), PCT (8.12 ± 1.90 ng/ml, 5.29 ± 1.28 ng/ml), IL-6 (256.40 ± 76.45 pg/ml, 174.14 ± 30.60 pg/ml), and IL-8 (134.71 ± 33.21 pg/ml, 84.40 ± 14.94 pg/ml) were detected in the mice of model and GR group compared to those in the mice of the control group (all P < 0.01); while the levels of CRP, PCT, IL-6, and IL-8 of the mice of GR group were significantly lower than those of the mice in the model group (P < 0.01 for all). Neatly arranged tracheal epithelium cilium and intact alveolar structure were observed but no inflammatory secretion in alveolar spaces was found in the mice of control group; whereas, obvious pathological changes were discovered in the mice of model group, including narrowed bronchial cavities, large amount of inflammatory secretion and inflammatory cell infiltration in alveolar spaces. Compared to those in the mice of model group, decreased amount of inflammatory secretion and alleviated inflammation were discovered in the mice of GR group.

  Conclusion  Gentiana rhodantha could prevent lung inflammation caused by Streptococcus pneumoniae in mice.