Abstract:

Objective  To observe the effect of simvastatin on inflammatory factors and lung pathology of the chronic obstructive pulmonary disease (COPD) rat model, and to investigate the therapeutic action of simvastatin on COPD. Methods  The COPD rat model was established by intratracheal instillation of lipopolysaccharide twice and exposure to daily cigarette. 30 male Wistar rats were randomly divided into three groups: the normal control group, the COPD model group and simvastatintreated group. The simvastatin treated group was treated with  2.5mg/kg simvastatin daily from the end of the second week for 6 weeks. The weight growth of each group, and total and differential cell counts in bronchoalveolar lavage fluid (BALF) were observed and  the pathomorphological changes in the lung were analyzed. IL-8 and TNF-α levels in BALF and serum, and CRP level in the serum were determined. Results  The weight growth rate of the simvastatin treated group was significantly higher than that of the COPD model group(P＜0.05). Pathological changes of COPD were observed in the COPD rat model. Airway inflammation was significantly increased in the COPD model group and emphysema was observed, which also appeared in the simvastatin treated group to a lighter degree. The total inflammatory cells and the proportion of neutrophils in BALF increased in the COPD model group compared with  the normal control group, while they were  significantly decreased in the simvastatin treated group(P＜0.05). IL-8 and TNF-α levels in BALF and serum were more significantly decreased  in the simvastatin treated group than in the COPD model group (P＜0.05), and CRP level in the serum also decreased in the simvastatin treated group (P＜0.05). Conclusion  Simvastatin can reduce inflammatory factors in BALF and the serum of the COPD rat model and decrease  inflammation of the lung tissue and airway. So simvastatin can inhibit the inflammation of the COPD rat model.

Key words: Pulmonary disease， chronic obstructive； Inflammation； Rats， Wistar； Simvastatin