Effect of microRNA-21 on proliferation and differentiation of pulmonary fibroblasts of mice / 天津医药

ABSTRACT

Objective To investigate the effect of microRNA(miR)-21 on proliferation and differentiation of murine pulmonary fibroblasts. Methods C57BL/6 mice of SPF grade (n=24) were randomly divided into Sham group and Pulmo?nary fibrosis model group with 12 mice in each group. Pulmonary fibrosis model was established by trans-tracheal jet ventila?tion of bleomycin into mice. The transcription levels of miR-21 were examined by quantitative real-time PCR in various pul?monary fibrosis tissues. Primary fibroblast were isolated and digested by Trypsin then inoculated into 6 well plate to reach confluence of 30%-50%. PBS (2.5μL), negative control stock solution and miR-21 mimic stock solution (20μmol/L) were added into Opti-MEM (50μL) as control group, blank group and miR-21 mimic group respectively.The cell viability was as?sessed by CCK-8. Expressions of ADAMTS-1 and TGF-β1 in the pulmonary fibroblasts were tested using Western blot. Re?sults The expression of miR-21 was significantly increased in lungs of mice in pulmonary fibrosis model group than that in sham group. Expression of miR-21 was higher in miR-21 mimic group than that in control group and blank group. Expres?sion of miR-21 was significantly higher with better cell viability in miR-21 mimic group than that in control group and blank group. The expression of ADAMTS-1 was significantly decreased in miR-21mimic group, while the expression of TGF-β1, a target gene of miR-21, was significantly increased in miR-21 mimic group compared with the other two groups. There is no significant different in expressions of ADAMTS-1 and TGF-β1 between control group and blank group. Conclusion Over?expression of miR-21 in pulmonary fibroblasts disrupts TGF-β1 signaling pathway by reducing expression of ADAMTS-1, which promotes the proliferation and differentiation of pulmonary fibroblast.