This study aims to investigate the influence ofβ-elemene on the secretion of angiotensin II(ANG II)and the expression of angiotensin receptor type 1(AT1R)in hepatic stellate cells(HSCs).In vitro,HSC-T6 were cultured f...This study aims to investigate the influence ofβ-elemene on the secretion of angiotensin II(ANG II)and the expression of angiotensin receptor type 1(AT1R)in hepatic stellate cells(HSCs).In vitro,HSC-T6 were cultured for 24 hours and then treated with different doses ofβ-elemene(2.5,5 and 10 mg/L).A control group was also set up.The secretion of ANG II in the supernatant was detected by radioimmunoassay.The mRNA expression of AT1R at 4,12 and 24 h after treatment was detected by reverse transcription-polymerase chain reaction(RT-PCR),respectively.The protein expression of AT1R was detected by western blot.At the 4th h,the ANG II secretion in the supernatant was significantly inhibited by 10 mg/Lβ-elemene compared with the control group(P<0.05),while 5.0 mg/L and 2.5 mg/Lβ-elemene had no inhibitory effect on the secretion of ANG II(P>0.05).At the time point of the 12th h,the secretion of ANG II in the supernatant treated with 10 mg/L and 5.0 mg/Lβ-elemene was significantly lower than the control(P<0.01,P<0.05).Following the treatment with 5.0 mg/L and 2.5 mg/Lβ-elemene for 24 h,significant inhibition of ANG II secretion was observed(P<0.05),but 10 mg/Lβ-elemene had no such effect.β-elemene significantly reduced the amount of AT1R mRNA in HSCs after the treatment for 4,12,and 24 h in a dose-dependent manner.The expression of AT1R protein also decreased after the treatment withβ-elemene for 24 h.β-elemene can inhibit the secretion of ANG II and the gene and protein expression of AT1R,which may be the mechanism by whichβ-elemene prevents the progress of hepaticfibrosis.展开更多
The aim of this study is to investigate the effects of RNA interference(RNAi)targeting angiotensin 1a receptor(AT1a)on blood pressure and cardiac hypertrophy of rats with renovascular hypertension.Two RNAi plasmids,pA...The aim of this study is to investigate the effects of RNA interference(RNAi)targeting angiotensin 1a receptor(AT1a)on blood pressure and cardiac hypertrophy of rats with renovascular hypertension.Two RNAi plasmids,pAT1a-shRNA1 and pAT1ashRNA2 each carrying a U6 promoter and an AT1aspecific shRNA-coding template sequence corresponding to the sites 928-946,978-996 of the mRNA transcript,and a control plasmid pCon carrying a nonspecific shRNA-coding sequence were constructed.Thirty Sprague-Dawley rats with renovascular hypertension(2-kidney 1-clip)were randomly divided into 5 equal groups:Control group(without any intervention),pAT1a-shRNA1,pAT1a-shRNA2,pCon groups(with injection of the corresponding plasmid 4 mg/kg respectively into the tail vein),and valsartan group(30 mg/kg·d^(-1) by gavage).Three weeks after drug administration,pAT1a-shRNA1,pAT1a-shRNA2 and valsartan respectively resulted in decrease of the tail blood pressure by(15.1±5.4),(16.4±8.4)and(30.6±18.2)mmHg.However,the tail blood pressure increased further by about 25 mmHg in both of pCon and control groups.The carotid artery pressures of pAT1a-shRNA1,pAT1ashRNA2 and valsartan groups were all significantly lower than those of the control and pCon groups.The ratio of left ventricle weight to body weight(LV/BW)of the rats in pAT1a-shRNA1,pAT1a-shRNA2,and valsartan groups decreased significantly than in the control group(P<0.01),similar to those of the normal SD rats(P>0.05).Histopathological examination showed that the myocardiocytes were significantly hypertrophic and the basal membrane of the aorta was significantly thickened in the control group and such changes were alleviated in the pAT1a-shRNA1,pAT1a-shRNA2 and valsartan groups.Compared with the control group,pAT1a-shRNA1 and pAT1a-shRNA2 groups had lowered expression of AT1 receptor(in the myocardium and the thoracic aorta(all P<0.01);however,there were no significant differences in expression levels of AT1 receptor in valsartan and the control groups(P>0.05).We conclude that RNAi targeting AT1a receptor inhibits the development of renovascular hypertension and the accompanying cardiac hypertrophy.RNAi technology may become a new strategy of gene therapy for hypertension.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.30500658).
文摘This study aims to investigate the influence ofβ-elemene on the secretion of angiotensin II(ANG II)and the expression of angiotensin receptor type 1(AT1R)in hepatic stellate cells(HSCs).In vitro,HSC-T6 were cultured for 24 hours and then treated with different doses ofβ-elemene(2.5,5 and 10 mg/L).A control group was also set up.The secretion of ANG II in the supernatant was detected by radioimmunoassay.The mRNA expression of AT1R at 4,12 and 24 h after treatment was detected by reverse transcription-polymerase chain reaction(RT-PCR),respectively.The protein expression of AT1R was detected by western blot.At the 4th h,the ANG II secretion in the supernatant was significantly inhibited by 10 mg/Lβ-elemene compared with the control group(P<0.05),while 5.0 mg/L and 2.5 mg/Lβ-elemene had no inhibitory effect on the secretion of ANG II(P>0.05).At the time point of the 12th h,the secretion of ANG II in the supernatant treated with 10 mg/L and 5.0 mg/Lβ-elemene was significantly lower than the control(P<0.01,P<0.05).Following the treatment with 5.0 mg/L and 2.5 mg/Lβ-elemene for 24 h,significant inhibition of ANG II secretion was observed(P<0.05),but 10 mg/Lβ-elemene had no such effect.β-elemene significantly reduced the amount of AT1R mRNA in HSCs after the treatment for 4,12,and 24 h in a dose-dependent manner.The expression of AT1R protein also decreased after the treatment withβ-elemene for 24 h.β-elemene can inhibit the secretion of ANG II and the gene and protein expression of AT1R,which may be the mechanism by whichβ-elemene prevents the progress of hepaticfibrosis.
文摘The aim of this study is to investigate the effects of RNA interference(RNAi)targeting angiotensin 1a receptor(AT1a)on blood pressure and cardiac hypertrophy of rats with renovascular hypertension.Two RNAi plasmids,pAT1a-shRNA1 and pAT1ashRNA2 each carrying a U6 promoter and an AT1aspecific shRNA-coding template sequence corresponding to the sites 928-946,978-996 of the mRNA transcript,and a control plasmid pCon carrying a nonspecific shRNA-coding sequence were constructed.Thirty Sprague-Dawley rats with renovascular hypertension(2-kidney 1-clip)were randomly divided into 5 equal groups:Control group(without any intervention),pAT1a-shRNA1,pAT1a-shRNA2,pCon groups(with injection of the corresponding plasmid 4 mg/kg respectively into the tail vein),and valsartan group(30 mg/kg·d^(-1) by gavage).Three weeks after drug administration,pAT1a-shRNA1,pAT1a-shRNA2 and valsartan respectively resulted in decrease of the tail blood pressure by(15.1±5.4),(16.4±8.4)and(30.6±18.2)mmHg.However,the tail blood pressure increased further by about 25 mmHg in both of pCon and control groups.The carotid artery pressures of pAT1a-shRNA1,pAT1ashRNA2 and valsartan groups were all significantly lower than those of the control and pCon groups.The ratio of left ventricle weight to body weight(LV/BW)of the rats in pAT1a-shRNA1,pAT1a-shRNA2,and valsartan groups decreased significantly than in the control group(P<0.01),similar to those of the normal SD rats(P>0.05).Histopathological examination showed that the myocardiocytes were significantly hypertrophic and the basal membrane of the aorta was significantly thickened in the control group and such changes were alleviated in the pAT1a-shRNA1,pAT1a-shRNA2 and valsartan groups.Compared with the control group,pAT1a-shRNA1 and pAT1a-shRNA2 groups had lowered expression of AT1 receptor(in the myocardium and the thoracic aorta(all P<0.01);however,there were no significant differences in expression levels of AT1 receptor in valsartan and the control groups(P>0.05).We conclude that RNAi targeting AT1a receptor inhibits the development of renovascular hypertension and the accompanying cardiac hypertrophy.RNAi technology may become a new strategy of gene therapy for hypertension.
