Inhibition of microRNA195 attenuates high-glucose induced neonatal cardiomyocytes hypertrophy in vitro
10.3760/cma.j.issn.0253-3758.2015.08.014
- VernacularTitle:微小RNA-195在糖尿病心肌病乳鼠心肌肥大中的作用及其机制
- Author:
Biao KONG
1
;
Dongli SHEN
;
Tao RUI
;
Guohui ZHANG
Author Information
1. 江苏大学附属人民医院心内科
- Keywords:
Diabetes mellitus;
Cardiomyopathies;
MicroRNAs
- From:
Chinese Journal of Cardiology
2015;43(8):712-717
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of micro (mi)RNA-195 on high-glucose induced neonatal cardiomyocyte hypertrophy and to explore the related mechanism.Methods The potential target gene of miRNA-195 (Smad7) was predicted by TargetScanS.1 software.Cardiomyocytes were isolated from neonatal SD rats and cells were then randomly divided into three groups:cells treated by culture medium containing 5 mmol/L glucose (control group),by culture medium containing 25 mmol/L glucose (high glucose group) and treated by culture medium containing 25 mmol/L glucose and miRNA-195 inhibitor transfection (miRNA-195 inhibitor group).After 24,48,or 72 h of in vitro culture,the morphology of cardiomyocytes was examined under phase contrast microscope.Micrographs were captured and the cell surface was calculated.The mRNA expressions of miRNA-195 and myosin heavy chain β (β-MHC),a biomarker for cardiomyocyte hypertrophy,in cardiomyocytes were detected by RT-PCR.The protein expression of Smad7 was determined by Western blot.The concentration of transforming growth factor-β1 (TGF-β1) in the supernatant of culture medium was measured by ELISA.Results Cross-sectional area of cardiomyocytes,expression of miRNA-195 and β-MHC and secretion of TGF-β1 were significantly increased in high glucose-treated cells (P ＜ 0.05 vs.normal control).The protein expression of Smad7 was significantly downregulated in cells exposed to high glucose for 48 h (P ＜ 0.05 vs.normal control).Downregulation of miRNA-195 partly reversed the high glucose-induced effects.The expression of Smad7 was negatively correlated with miRNA-195 in high glucose control group (correlation coefficient:-0.945,P ＜ 0.05).Conclusion Our results demonstrate that Smad7 could be the target gene of miRNA-195.miRNA-195 might play a crucial role in the development and progression of diabetic cardiomyopathy possibly through downregulating the expression of Smad7 and modulating TGF-β/Smad pathways.
