Aberrant increases in protein phosphatase 1(PP1) activity have been shown to be associated with inefficient sarcoplasmic reticulum Ca^{2+} cycling, leading to cardiac dysfunction in the failing heart. In the present study, we investigated whether BNP promoter-inducible suppression of PP1β would ameliorate progression of pressure overload-induced heart failure in mice, a clinically relevant animal model. An Adeno-associated virus 9 (AAV9) vector encoding PP1βshRNA and a negative control (NC) shRNA driven by a brain natriuretic peptide (BNP) promoter with an emerald green fluorescent protein expression (EmGFP) cassette were used to test the hypothesis. AAV9 vectors (AAV9-BNP-EmGFP-PP1βshRNA and AAV9-BNP-EmGFP-NCshRNA) were introduced into the in vivo heart via the tail vein injection (4x10^{11} GC/mice) in 8-week-old C57BL6J mice, followed by transverse aortic constriction (TAC) 2 weeks after the AAV9 vector injection. Post TAC cardiac function was sequentially assessed every 2 week by echocardiography, followed by hemodynamic assessment at 1 month. AAV9-BNP-EmGFP-PP1βshRNA treatment suppressed myocardial PP1β expression by 15% compared with the NCshRNA group (p<0.001). The fractional shortening (%FS) of the left ventricle in the PP1βshRNA-treated group was significantly larger than the NCshRNA-treated group (21%±1.0% vs. 15%±0.01, p<0.01). The ratios of heart weight (HW) / body weight (BW) and lung weight (LW) / BW in the PP1βshRNA group were significantly smaller than those of the NCshRNA group (HW/BW: 9.20±0.49 vs. 10.6±0.45 mg/g

Background The lipid-lowering therapy by statins may stabilize and reduce coronary plaques. We compare the effect of strong or moderate statins on the coronary plaque characteristics by using 64-slice multidetector computed tomography (MDCT). Methods and Results We analyzed 13 subjects with non-calcified coronary plaques(NCP)as determined by MDCT. Pitavastatin(PTV:2mg/day)or pravastatin(PRA:10mg/day)were randomly administered. MDCT were performed at 0, 6 and 12 months after lipid-lowering therapy. In PTV group(n=6),CT density of NCP increased by 35.6 ± 28.8 HU after 6 months(p=0.037)and by 30.6 ± 29.8 HU after 12 months(NS).NCP area was decreased by 35.9 ± 15.2 % after 6 months and by 41.0 ± 16.5 % after 12 months(both P=0.001).In PRA group(n=7),CT density of NCP did not significantly increased after 6 months(NS)and after 12 months(NS).NCP area was not significantly decreased at 6 months(NS),but decreased by 23.1 ± 16.7 % at 12 months(P=0.001). Conclusions Serial CT angiography revealed that the regression of NCP occurs rapidly by strong lipid lowering therapy compared to the moderate statin therapy.