KDM2A在博来霉素诱导肺纤维化小鼠中的表达

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

目的 探讨KDM2A在肺纤维化进展中的表达变化,以期为寻求肺纤维化的发病机制提供具有潜力的新方向。方法 将8~10周的C57BL/6J雄性小鼠随机分配为正常组、14 d模型组与21 d模型组。取模型组小鼠麻醉后,气道滴定博来霉素诱导建立肺纤维化模型。分别于造模后第14天、第21天取材14 d模型组与21 d模型组小鼠肺组织,最后取材正常组小鼠肺组织。通过HE染色,Masson染色来评估小鼠肺泡炎及纤维化程度。免疫组化分析3组肺组织α-SMA、FN、TGF-β1及KDM2A蛋白表达情况并进行免疫组化评分。Western Blot法检测α-SMA、FN、TGF-β1及KDM2A蛋白表达量。结果 与正常组比较,14 d模型组肺泡炎评分明显增加(P<0.001);21 d模型组较14 d模型组比较,肺泡炎评分轻度增加,但差异无统计学意义(P>0.05)。与正常组比较,14 d模型组纤维化评分明显增加(P<0.01);21 d模型组较14 d模型组比较,纤维化评分明显增加(P<0.01)。免疫组织化学染色结果显示:与正常组比较,14 d模型组α-SMA(P<0.01)、FN(P<0.01)、TGF-β1(P<0.01)、KDM2A(P<0.01)蛋白免疫组化评分明显升高;21 d模型组较14 d模型组比较,α-SMA(P<0.01)、FN(P<0.05)、TGF-β1(P<0.01)、KDM2A(P<0.01)蛋白免疫组化评分升高。Western Blot结果显示:与正常组比较,14 d模型组α-SMA(P<0.01)、FN(P<0.01)、TGF-β1(P<0.01)、KDM2A(P<0.01)蛋白表达量明显升高;21 d模型组较14 d模型组相比,α-SMA(P<0.01)、FN(P<0.01)、TGF-β1(P<0.01)、KDM2A(P<0.01)蛋白表达量升高。结论 KDM2A在BLM诱导的肺纤维化小鼠肺组织中表达增强,其可能通过调控TGF-β1的表达来参与肺纤维化的形成。

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 21d 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 21d 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 ofα-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 21d 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 ofα-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 ofα-SMA(P<0.01),FN(P<0.05),TGF-β1(P<0.01)and KDM2A(P<0.01)in the 21d 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 ofα-SMA(P<0.01),FN(P<0.01),TGF-β1(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.