Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive ...Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive patients.However,the causal relationship between miR-29a and LV remodeling remains unknown.Thus,the aim of this study was to investigate the regulation mechanism of miR-29a in LV remodeling.Methods&Results Overexpression and knockdown miR-29a mice were generated by tail-intravenous injection of miR-29a-mimic and inhibitor lentivirus for one week respectively.Then the mice were subjected to angiotensin-II(AngII)induced LV remodeling by subcutaneous AngII capsule osmotic pumping into AngII for four weeks.AngII-induced LV remodeling mice as the model group(n=9).Age-matched male SPF C57/BL6J mice(6–8 weeks old)were treated with the pumping of saline as a vehicle(n=6).In vivo,overexpression miR-29a ameliorated AngII-induced LV remodeling,while knockdown miR-29a deteriorated LV remodeling.Simultaneously,we observed that overexpression miR-29a mice inhibited but knockdown miR-29a mice increased cardiac cross-sectional area,indicating that miR-29a has an antagonistic effect on cardiac hypertrophy.Further studies found that overexpression miR-29a inhibited the content of the LV collagen including collagen I and III.Moreover,the expression of transforming growth factor-β(TGF-β)and phosphorylated SMAD2/3 decreased with the down-regulation of collagen I and III in overexpression miR-29a mice.Conclusions Our finding indicates that overexpression miR-29a attenuates LV remodeling by inhibiting collagen deposition,TGF-β,and phosphorylated SMAD2/3 expression.Thus,intervention miR-29a may be a therapeutic target for attenuating LV remodeling.展开更多
基金supported by the National Natural Science Foundation of China(No.81570383)
文摘Background Left ventricular(LV)remodeling is the most common target organ damage in hypertension.Previously,our study found that plasma microRNA-29a(miR-29a)level was associated with the LV remodeling in hypertensive patients.However,the causal relationship between miR-29a and LV remodeling remains unknown.Thus,the aim of this study was to investigate the regulation mechanism of miR-29a in LV remodeling.Methods&Results Overexpression and knockdown miR-29a mice were generated by tail-intravenous injection of miR-29a-mimic and inhibitor lentivirus for one week respectively.Then the mice were subjected to angiotensin-II(AngII)induced LV remodeling by subcutaneous AngII capsule osmotic pumping into AngII for four weeks.AngII-induced LV remodeling mice as the model group(n=9).Age-matched male SPF C57/BL6J mice(6–8 weeks old)were treated with the pumping of saline as a vehicle(n=6).In vivo,overexpression miR-29a ameliorated AngII-induced LV remodeling,while knockdown miR-29a deteriorated LV remodeling.Simultaneously,we observed that overexpression miR-29a mice inhibited but knockdown miR-29a mice increased cardiac cross-sectional area,indicating that miR-29a has an antagonistic effect on cardiac hypertrophy.Further studies found that overexpression miR-29a inhibited the content of the LV collagen including collagen I and III.Moreover,the expression of transforming growth factor-β(TGF-β)and phosphorylated SMAD2/3 decreased with the down-regulation of collagen I and III in overexpression miR-29a mice.Conclusions Our finding indicates that overexpression miR-29a attenuates LV remodeling by inhibiting collagen deposition,TGF-β,and phosphorylated SMAD2/3 expression.Thus,intervention miR-29a may be a therapeutic target for attenuating LV remodeling.
