Effects of Baicalin and Ligustrazine on airway inflammation and remodeling and underlying mechanism in asthmatic rats

Aim: To explore the effects of Baicalin and Ligustrazine on airway inflammation and construction and underlying mechanisms through the expressions of GATA-3, IL-5, MMP-9 and TIMP-1 in asthmatic rats. Methods: 30 Wistar rats were randomly divided equally into five groups. Lung tissues were sliced. WBC and Eos in lung tissue were estimated by HE stain and the expressions of IL-5, GATA-3, MMP-9, TIMP-1 and collagen type IV in lung tissue were observed by immunohistochemistry. The airway wall and airway smooth muscle thicknesses were measured by computed image analysis system. Results: Compared with asthma group, EOS counts and the expression of IL-5 and GATA-3 in the lung tissue were significantly lower in normal controlled groups (P < 0.05 or P < 0.01). Additionally, the thickness of airway wall and airway smooth muscle did significantly increase, and the expressions of collagen type Ⅳ, MMP-9 and TIMP-1 were significantly higher in asthma group (P < 0.05). With the intervention of Baicalin or Ligustrazine, EOS decreased, and the thicknesses of airway wall and airway smooth muscle became thinner compared with asthma group. Meanwhile, the expression of collagen type IV, IL-5, GATA-3, MMP-9 and TIMP-1 significantly decreased (P < 0.05). Airway wall thickness and collagen type Ⅳ were associated with Eos, IL-5, TAGA-3, MMP-9, TIMP-1 and MMP-9/ TIMP-1. Conclusion: Two herbs could diminish infiltration of EOS with inhibiting the expressions of IL-5, and GATA-3, meanwhile, decrease the deposition of collagen type IV and the thickness of the airway smooth muscle through regulating MMP-9, TIMP-1 level and the balance between MMP-9 and TIMP-1, additionally, had synergetic effects.