Expression changes of KDM2A in bleomycin-induced pulmonary fibrosis in mice

LI Ning; WANG Zhixia; YUAN Xiaomei

doi:10.3969/j.issn.1002-7386.2024.16.002

Abstract：Objective To investigate the expression changes of KDM2A in the progression of pulmonary fibrosis,thus providing a potential new direction for unveiling the pathogenesis of pulmonary fibrosis.Methods Male C57BL/6J mice from 8 weeks to 10 weeks of age were randomly assigned to 3 groups:normal group(n=11),14d model group(n=11)and 21 d model group(n=11).After anesthesia,intratracheal bleomycin(BLM)was used to induce pulmonary fibrosis in the model group.On the 14th and 21st day after modeling,mouse lung tissues in the 14d model group and 21 d model group were collected,respectively.Mouse lung tissues in the normal group were collected at the end of the experimental period.The hematoxylin and eosin(H&E)staining and Masson staining were used to evaluate the degree of alveolitis and fibrosis in mice,respectively.The protein expressions of alpha-smooth muscle actin(α-SMA),fibronectin(FN),transforming growth factor-beta1(TGF-β1)and KDM2A in lung tissues were analyzed by immunohistochemistry,and immunohistochemical scores were graded.The protein expression levels of α-SMA,FN,TGF-β1 and KDM2A were detected by Western blot as well.Results Compared with that of the normal group,the alveolitis score in the 14d model group was significantly higher(P＜0.01).It was higher in the 21 d model group than that of 14d model group,but the difference was not statistically significant(P＞0.05).Compared with that of the normal group,the fibrosis score of the 14d model group was significantly higher(P＜0.01).It was significantly higher in the 21d model group than that of 14d model group(P＜0.01).Immunohistochemical scores of α-SMA(P＜0.01),FN(P＜0.01),TGF-β1(P＜0.01)and KDM2A(P＜0.01)in 14d model group were significantly higher than those of normal group.Immunohistochemical scores of α-SMA(P＜0.01),FN(P＜0.05),TGF-β1(P＜0.01)and KDM2A(P＜0.01)in the 21 d model group were significantly higher than those of 14d model group.Western blot results showed that compared with those of the normal group,the protein expressions of α-SMA(P＜0.01),FN(P＜0.01),TGF-p1(P＜0.01)and KDM2A(P＜0.01)in the 14d model group were significantly upregulated.The protein expressions ofα-SMA(P＜0.01),FN(P＜0.01),TGF-β1(P＜0.01)and KDM2A(P＜0.01)were significantly upregulated in the 21d model group compared with those of 14d model group.Conclusion KDM2A is overexpressed in the lung tissues of BLM-induced pulmonary fibrosis in mice by regulating the expression of TGF-β1.