The effect of CORM-2 on pulmonary fibrosis of aged mice induced by paraquat and its mechanism

Objective To observe the protection effect of carbon monoxide releasing molecule-2(CORM-2) performed in aged mice pulmonary fibrosis induced by Paraquat(PQ) and its mechanism.Methods 72 aged mice were divided into sham,paraquat,CORM-2 + paraquat,iCORM-2 + paraquat groups,each group had 18 mice.Six mice from each group were killed randomly 3,5 and 7 d post-drug administration,and artery blood,serum and lung tissues were harvested respectively,the level of arterial oxygen partial pressure between groups was analyzed,the serum level of TNF-α and the lung tissues levels of MDA,MPO were analyzed by ELISA,the degree of lung injury was also analyzed by the lung tissue wet dry ratio and the protein level of BALF,the degree of pulmonary fibrosis between groups were contrasted by cellulose dyeing,inducible nitric oxide synthase(iNOS) level in lung tissues was analyzed by Western blot.Results Compared with those of sham group,artery blood oxygen partial pressure was decreased and the lung tissue levels of MDA,MPO were increased,these changes in paraquat and iCORM-2 + paraquat groups were more apparent,but there were not significant differences between paraquat and iCORM-2 + paraquat groups.In CORM-2 + paraquat group,the lung injury and pulmonary fibrosis were alleviated,and had significant difference.Conclusions CORM-2 can protect lung injury of pulmonary fibrosis aged mice induced by paraquat,through suppressing oxidation activity by carbon monoxide.It also inhibits iNOS expression so as to improve lung function