Effects of RNA interference targeting angiotensin 1 receptor and angiotensin-converting enzyme on blood pressure and myocardial remodeling in spontaneous hypertensive rats / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effects of RNA interference (RNAi) targeting angiotensin II Type 1 receptor (ATlR) and angiotensin-converting enzyme (ACE) on blood pressure and myocardial remodeling in spontaneous hypertensive rats (SHRs).</p><p><b>METHODS</b>Saline (control), adenovirus (Ad5) and recombinant adenoviral vectors (Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA expressing ACE, AT1R, ACE and AT1R gene-specific shRNA, respectively) were randomly administered by caudal intravasation to SHRs (n = 12 each group) at day 1 and 17. Normotensive Wistar-Kyoto rats (WKY) served as normal controls. Systolic blood pressure (SBP) of the caudal artery was measured daily. Expression of ACE and AT1R at mRNA levels in ventricle and aorta were evaluated by fluorescence quantitative PCR. Angiotension II serum concentration was measured by ELISA at day 3 (n = 6 each group). The ratio of left ventricular to body weight (LVW/BW) and myocardial collagen content were measured, myocardial ultrastructure observed under transmission electron microscope at the study end.</p><p><b>RESULTS</b>The caudal artery pressure of saline and Ad5 group was equally increased by about 26 mm Hg(1 mm Hg = 0.133 kPa) compared to baseline (both P < 0.05). Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA injection significantly reduced SBP (-24 mm Hg, -22 mm Hg and -26 mm Hg respectively, all P < 0.05 vs. baseline) and the antihypertensive effect could last at least 15 days post each injection. SBP was not affected by saline and Ad5 injections. ACE and AT1 mRNA expressions at ventricle and aorta were significantly decreased in Ad5-ACE-shRNA, Ad5-ACE-AT1R-shRNA and Ad5-AT1R-shRNA, Ad5-ACE-AT1R-shRNA treated SHRs compared to those in saline and Ad5 groups (all P < 0.05) and was comparable to that in WKY group (P > 0.05). The LVW/BW ratio [(2.22 +/- 0.18) microg/mg, (2.23 +/- 0.19) microg/mg, (2.17 +/- 0.16) microg/mg] and myocardial collagen content [(1.291 +/- 0.019) microg/mg, (1.298 +/- 0.019) microg/mg, (1.276 +/- 0.019) microg/mg] in Ad5-ACE-shRNA, Ad5-AT1R-shRNA and Ad5-ACE-AT1R-shRNA treated SHRs were also significantly lower than those in saline treated [(3.23 +/- 0.13) microg/mg and(1.683 +/- 0.013) microg/mg, both P < 0.05] and Ad5 treated SHRs [(3.25 +/- 0.12) microg/mg and(1.693 +/- 0.013) microg/mg, both P < 0.05], but still higher than those of WKY group [(2.06 +/- 0.12) microg/mg and (1.258 +/- 0.019) microg/mg, both P < 0.05]. Myocardial ultrastructure was also significantly improved in all SHRs underwent RNAi treatments compared to saline and Ad5 treated SHRs.</p><p><b>CONCLUSION</b>RNAi targeting ACE and AT1R gene significantly inhibited myocardial and aortic ACE and AT1R mRNA expressions and resulted in prolonged antihypertensive effects and myocardial ultrastructure improvements in SHRsl. The RNAi technology may be a potential new strategy of gene therapy for hypertension.</p>

Effects of RNA interference targeting angiotensin-converting enzyme on the blood pressure and myocardial remodeling in spontaneously hypertensive rats / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effects of RNA interference (RNAi) targeting angiotensin-converting enzyme (ACE) on the blood pressure and myocardial remodeling in spontaneously hypertensive rats (SHRs).</p><p><b>METHODS</b>Saline (control), adenovirus (Ad5) and recombinant adenoviral vectors (Ad5-ACE-shRNA expressing ACE gene-specific shRN) were randomly administered by caudal intravasation to SHRs (n = 12 each group) at day 1 and day 16. Normotensive Wistar-Kyoto rats (WKY) served as normal controls. Systolic blood pressure (SBP) of the caudal artery was measured daily. Expressions of ACE at mRNA and protein levels in myocardium and aorta were evaluated by RT-PCR and Western blot respectively, ACE serum concentration was measured by ELISA at day 3 (n = 6 each group). The ratio of left ventricular to body weight (LVW/BW), myocardial collagen content were measured and myocardial ultrastructure observed under transmission electron microscope at the study end.</p><p><b>RESULTS</b>Ad5-ACE-shRNA injection significantly reduced SBP (-22 mm Hg, 1 mm Hg = 0.133 kPa) and the antihypertensive effect could last at least 14 days post each injection. SBP was not affected by saline and Ad5 injections. ACE expressions at mRNA and protein levels at myocardium and aorta as well as serum ACE were significantly decreased in Ad5-ACE-shRNA treated SHRs compared to that in saline and Ad5 groups (all P < 0.05) and was comparable to that in WKY group (P > 0.05). The LVW/BW ratio (2.24 +/- 0.19) and myocardial collagen content [(1.283 +/- 0.019) microg/mg] in Ad5-ACE-shRNA treated SHRs were also significantly lower than those in saline treated [3.21 +/- 0.13 and (1.686 +/- 0.013) microg/mg, both P < 0.05] and Ad5 treated SHRs [3.13 +/- 0.12, (1.682 +/- 0.009) microg/mg, both P < 0.05] but still higher than those of WKY group [2.06 +/- 0.11, (1.257 +/- 0.019) microg/mg, both P < 0.05]. Myocardial ultrastructure was also significantly improved in Ad5-ACE-shRNA treated SHRs compared to saline and Ad5 treated SHRs.</p><p><b>CONCLUSION</b>RNAi targeting ACE gene significantly inhibited the expressions of ACE at mRNA and protein levels and resulted in prolonged antihypertensive effects and myocardial ultrastructure improvements in this SHR model.</p>

Time course of G-CSF, estrogen and various doses of atorvastatin on endothelial progenitor cells mobilization / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate the time course of granulocyte-colony-stimulating-factor (G-CSF), estrogen and various doses of atorvastatin on endothelial progenitor cells (EPCs) mobilization.</p><p><b>METHOD</b>A total of 48 male New Zealand White rabbits were treated with placebo, estrogen (0.25 mg.k(-1).d(-1)), Atorvastatin (2.5, 5, or 10 mg) and G-CSF (50 microg/rabbit/d), respectively. Peripheral EPCs number was surveyed weekly for 4 weeks by FACS analysis (double-positive for PE-CD34/FITC-CD133) and under fluorescent microscope (double-positive for FITC-UEA-1/Dil-acLDL). Serum nitric oxide (NO) and lipids were also measured at the third week.</p><p><b>RESULTS</b>Peripheral EPCs was significantly increased in G-CSF treated animals and remained constant for 4 weeks compared to placebo treated animals. Atorvastatin increased peripheral EPCs dose-dependently from 2.5 to 5 mg and peaked at the third week while peripheral EPCs number was not affected by 10 mg.k(-1).d(-1) atorvastatin during the first 3 weeks and was significantly higher only in the fourth week compared to placebo group. Estrogen also significantly increased peripheral EPCs at the third and fourth week compared to placebo group. At the third week, serum NO was similar in G-CSF group, significantly higher in atorvastatin 5 mg.k(-1).d(-1) and estrogen groups while significantly lower in atorvastatin 10 mg.k(-1).d(-1) group compared to placebo group. Serum lipids were similar among various groups.</p><p><b>CONCLUSION</b>Atorvastatin, estrogen and G-CSF could mobilize EPCs. The mobilization efficacy is as follows: G-CSF > atorvastatin 5 mg.k(-1).d(-1) > estrogen > atorvastatin 2.5 mg.k(-1).d(-1) > atorvastatin 10 mg.k(-1).d(-1). NO might partly contribute to the mobilizing effect of estrogen and atorvastatin.</p>

Effects of Adenovirus-mediated Angiotensin-Converting Enzyme-shRNA on Spontaneously Hypertensive Rats / 中华高血压杂志

Background Hypertension is a multigenetic inheritable disease.Gene therapy with long-term effects and less side effects by regulating gene expression has been shown to be a potential and exciting prospect. Objective To investigate the effects of RNA interference(RNAi)targeting angiotensin-converting enzyme(ACE)on the blood pressure and ACE expression in kidney of spontaneously hypertensive rats(SHR).Methods SHR were randomly to receive placebo(n=12)or control adenovirus Ad5-EGFP)or a single injection of recombinant adenovi- ral vectors,Ad5-EGFP-ACE-shRNA(n=12,iv).Normotensive Wistar-Kyoto rats(WKY)were served as normal control group.SBP was measured before and after the intervention.Aorta,lung,myocardium and kidney were studied using fluorescence microscope to identify the sites of Ad5-EGFP-ACE-shRNA.Expressions of ACE mRNA and protein in kidney were evaluated by RT-PCR and Western blot.Results SBP of the treat group was effectively reduced by 19.0?3.2 mmHg at the 3rd day,and 22.1?3.3 mmHg at the 13th day of the experiment.The anti- hypertensive effect significant remained at least for 14 days.On the contrary,increase in BP was shown in placebo and the adenovirus control group.Compared with placebo or adenovirus control rats,ACE mRNA expression level in kidney of the treated rats was lower by 61.1% and 62.3% respectively,with ACE protein expression level lower- ing by 56.2% and 53.30% as well(ail P0.05). Conclusion RNA interference targeting ACE gene inhibits the expressions of ACE mRNA and protein.A single dose injection resulted in a prolonged decrease in BP.The evidence of strong antihypertensive effect by genetic therapy justifies efforts for further investigation.