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1. Previously, we showed that long-term treatment of rats after myocardial infarction (MI) with B-type natriuretic peptide (BNP) prevented ventricular remodelling. However, it is unclear whether long-term BNP treatment affects cardiac hypertrophy and, if so, its mechanism of action. In the present study, we investigated the effects of long-term BNP treatment on cardiac hypertrophy and the molecular mechanisms involved. 2. Cardiac hypertrophy was established in rats by ligation of the left anterior descending coronary artery . After treatment with BNP (5 or 15 μg/kg per day) for 8 weeks, indices of cardiac hypertrophy were determined. In separate in vitro experiments, cardiomyocyte hypertrophy was induced by treatment of cardiomyocytes with 10−6 mol/L angiotensin (Ang) II for 48 h and cell surface area and [3H] incorporation were measured. Transforming growth factor (TGF)-β1 and smad7 mRNA and protein expression in vivo and in vitro were detected using reverse transcription–polymerase chain reaction and western blotting. 3. Long-term BNP treatment dose-dependently attenuated cardiac hypertrophy and improved cardiac function in rats after MI. Furthermore, BNP attenuated the upregulation of TGF-β1 and downregulation of smad7 mRNA and protein expression. The in vitro experiments further proved that BNP inhibited cardiac hypertrophy and changes in the TGF-β1/smad7 pathway, which were completely blocked by the cyclic GMP-dependent protein kinase (PKG) inhibitor, KT5823 (cells were treated with 10−6 mol/L KT5823 for 48 h). 4. The results of the present study demonstrate that long-term treatment of rats with BNP dose-dependently attenuates cardiac hypertrophy and that this is associated with downregulation of TGF-β1 and upregulation of smad7 via PKG signalling. Long-term BNP treatment may be a new therapeutic strategy to prevent cardiac hypertrophy and progression to heart failure. [ABSTRACT FROM AUTHOR]

Objective: To explore illness perception (IP) and its predictors among Chinese patients with myocardial infarction (MI). Methods: The revised Illness Perception Questionnaire (IPQ-R) was used in the present study. A cross-sectional, descriptive design was employed. The study was conducted in four major hospitals in Guangzhou (China) with a sample of 193 MI patients. Pearson''s and Spearman''s correlation, t test, one-way ANOVA, factor analysis and multiple linear regression were used. Results: Among the 12 common symptoms of MI, on average only 3.37 were recognized by the subjects. Among the six factors of the cause dimension, “immune factors” received the highest score, followed by “gene and chance”, “behavioral factors”, “psychological factors”, “environmental factors”, and “physical factors”. Subjects perceived MI as a chronic, cyclic illness with serious consequences that could be controlled through treatment, and believed that they had a negative affective response to MI. Furthermore, the dimensions of patients’ IP were correlated, and illness-related factors and socio-demographic factors acted as predictors of IP. Conclusion: The IP of Chinese patients with MI needs to be improved. Practice implications: Based on our findings, effective interventions can be designed to promote MI patients’ IP to facilitate their coping strategies after an episode of MI. [Copyright &y& Elsevier]

The nonpeptide AVE0991 is an agonist of the angiotensin-(1-7) (Ang-(1-7)) Mas receptor and is expected to be a putative new drug for treatment of cardiovascular disease. However, the mechanisms involved in the antiproliferative effects of AVE0991 are not fully understood. We saw that the compound attenuated proliferation in an angiotensin II-induced rat vascular smooth muscle cells (VSMC) proliferation model.Moreover, treatment with AVE0991 (10-5 mol/L or 10-7 mol/L) significantly attenuated reactive oxygen species (ROS) production, phosphorylation of p38 MAPK, and dose-dependently (10-8 to 10-5 mol/L) inhibited Ang II-induced VSMC proliferation. Meanwhile, heme oxygenase-1 (HO-1) expression increased in the AVE0991 + Ang II group (10-5 mol/L or 10-6 mol/L).However, the beneficial effects of AVE0991 were completely abolished when the VSMC were pretreated with A-779 (10-6 mol/L). Furthermore, treatment with the HO-1 inhibitor ZnPPIX attenuated the inhibitory effect of AVE0991 on Ang II-induced p38MAPK phosphorylation. These results suggest that AVE0991 attenuates Ang II-induced VSMC proliferation in a dose-dependent fashion and that this effect is associated with the Mas/HO-1/p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

The nonpeptide AVE0991 is an agonist of the angiotensin-(1-7) (Ang-(1-7)) Mas receptor and is expected to be a putative new drug for treatment of cardiovascular disease. However, the mechanisms involved in the antiproliferative effects of AVE0991 are not fully understood. We saw that the compound attenuated proliferation in an angiotensin II-induced rat vascular smooth muscle cells (VSMC) proliferation model.Moreover, treatment with AVE0991 (10-5 mol/L or 10-7 mol/L) significantly attenuated reactive oxygen species (ROS) production, phosphorylation of p38 MAPK, and dose-dependently (10-8 to 10-5 mol/L) inhibited Ang II-induced VSMC proliferation. Meanwhile, heme oxygenase-1 (HO-1) expression increased in the AVE0991 + Ang II group (10-5 mol/L or 10-6 mol/L).However, the beneficial effects of AVE0991 were completely abolished when the VSMC were pretreated with A-779 (10-6 mol/L). Furthermore, treatment with the HO-1 inhibitor ZnPPIX attenuated the inhibitory effect of AVE0991 on Ang II-induced p38MAPK phosphorylation. These results suggest that AVE0991 attenuates Ang II-induced VSMC proliferation in a dose-dependent fashion and that this effect is associated with the Mas/HO-1/p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Cardiomyocyte stretching has been reported to be a major trigger for brain natriuretic peptide (BNP) release; however, an increase in circulating BNP is observed in patients with acute myocardial ischemia in the absence of increased left ventricular wall stress or cardiomyocyte stretching. In the present study, to investigate the direct and independent effects of acute myocardial ischemia on BNP expression and its mechanism, we established an in vitro glucose-free ischemia and hypoxia injured model of cultured rat cardiomyotes and proved hypoxia upregulated expressions of interleukin-6(il-6) and BNP. Further treatment with il-6 elicited dose- and time-dependent increases in BNP mRNA and protein expression as well as an upregulation in transforming growth factor-β1 (TGF-β1)/Smad2 expression, which was partially suppressed by a neutralizing antibody. In conclusion, our study showed that acute myocardial ischemia can directly upregulate BNP expression at the translational and transcriptional levels through the action of il-6, and this process is associated with the upregulation of TGF-β1/Smad2 signal path. [Copyright &y& Elsevier]

Abstract: Objective: Angiotensin-(1–7) [ANG-(1–7)] has been reported to attenuate neointimal formation after vascular injury and stent implantation in rats, but the mechanism remains mostly unresolved. Interestingly, the levels of circulating transforming growth factor-beta1 (TGF-β1) after myocardial infarction were suppressed by ANG-(1–7), which suggests a possible downstream target for the anti-remodeling action of ANG-(1–7). Our study focused on the effects of ANG-(1–7) on vascular remodeling, including neointimal formation and collagen synthesis, and determining whether or not these effects were dependent upon the TGF-β signaling pathway. Methods: Thirty-two New Zealand white rabbits underwent sham surgery or angioplasty in abdominal aorta. The animals were divided into four groups, which were sham, control, ANG-(1–7), and ANG-(1–7)+A-779. Subsequently, an osmotic minipump was implanted to deliver saline, ANG-(1–7) (576μgkg−1 d−1) or ANG-(1–7)+A-779 (576μgkg−1 d−1) for 4weeks. Results: The ANG-(1–7) group displayed a significant reduction in neointimal thickness (207.51±16.70μm vs. 448.08±15.30μm, P <0.001), neointimal area (0.266±0.009mm2 vs. 0.408±0.002mm2, P <0.001), and restenosis rate (28.13±2.74% vs. 40.13±2.74%, P <0.001) when compared to the control group. ANG-(1–7) also inhibited collagen synthesis by significantly decreasing the mRNA expression of Collagen I and Collagen III (vs. Control group: 0.2190±0.0036 vs. 0.3852±0.0212, P <0.001 and 1.1328±0.0554 vs. 1.7378±0.1164, P <0.001, respectively). Furthermore, the expression of TGF-β1 and phosphor-Smad2 (p-Smad2) were significantly suppressed by ANG-(1–7) (vs. Control group: 1.21±0.07 vs. 1.54±0.08, P <0.001 and 0.31±0.01 vs. 0.43±0.02, P <0.001, respectively), but no effect on p38 phosphorylation was observed. [d-Ala7]-ANG-(1–7) (A-779), showed a tendency to attenuate the anti-remodeling effects of ANG-(1–7). Conclusion: ANG-(1–7) decreases the amount of vascular remodeling, including a reduction in neointimal formation and collagen synthesis, after angioplasty in rabbits. The responsible mechanism may function through the possible down-regulation of TGF-β1 levels and inhibition of the Smad2 pathway. [Copyright &y& Elsevier]

1. It has been demonstrated that epigallocatechin-3-gallate (EGCG) inhibits cardiac hypertrophy through its antihypertensive and anti-oxidant effects. However, the underlying molecular mechanism is not clear. 2. In the present study, we tested the hypothesis that EGCG attenuates transaortic abdominal aortic constriction (TAC)-induced ventricular hypertrophy by regulating mitogen-activated protein kinase (MAPK) signal pathways in hypertensive rats. Four groups of rats were used: (i) a sham-operated control group; (ii) an EGCG-treated (50 mg/kg per day, i.p., for 21 days) sham-operated group; (iii) a TAC group; and (iv) an EGCG-treated TAC group. Histological analysis of whole hearts and biochemical analyses of left ventricular (LV) tissue were used to investigate the effects of EGCG. 3. The results showed that the LV myocyte diameter and the expression of atrial natriuretic peptide, brain natriuretic peptide and β-myocardial heavy chain were significantly decreased in the EGCG-treated (50 mg/kg per day, i.p.) TAC group. Levels of reactive oxygen species and malondialdehyde in the lV were significantly reduced by EGCG in the TAC group. Total superoxide dismutase, catalase and glutathione peroxidase activities were decreased in the TAC group, and this decrease was significantly restored by EGCG treatment. Phosphorylation of extracellular signal-regulated kinase 2, p38 and c-Jun N-terminal kinase 1 was significantly reversed in the LV of EGCG-treated TAC rats (40%, 53% and 52% vs TAC, respectively), accompanied by significant inhibition of nuclear factor-κB and activator protein-1. Transaortic abdominal aortic constriction significantly upregulated LV expression of matrix metalloproteinase-9 from 32 ± 6 to 100 ± 12% and this increase was inhibited by EGCG treatment (from 100 ± 12 to 50 ± 15%). In addition, TAC decreased mitochondrial DNA copy number and the activity of respiratory chain complexes I (from 100 ± 7 to 68 ± 5%), III (from 100 ± 4 to 2 ± 5%) and IV (from 766 ± 2 to 100 ± 5%); this decrease was reversed by EGCG treatment to levels seen in sham-operated rats. 4. In conclusion, EGCG attenuates TAC-induced ventricular hypertrophy in hypertensive rats in part by suppression of anti-oxidant enzymes and regulation of MAPK signals. [ABSTRACT FROM AUTHOR]

Background: The cardiovascular (CV) safety in terms of heart failure among different classes of treatment remains largely unknown. We sought to assess the comparative effect of these agents on heart failure outcomes. Methods: This study was registered in the International Prospective Register of Systematic Reviews (CRD 42016042063). MEDLINE, EMBASE, and the Cochrane Library Central Register of Controlled Trials were searched. For the primary outcomes reported previously, studies between Jan 1, 1980 and June 30, 2016 were screened, and subsequently updated till Jan 24, 2019. We performed network meta-analysis to obtain estimates for the outcomes of heart failure, in particular by rankograms for ranking of heart failure risk as well as by pairwise comparisons among all classes of anti-diabetic medications. Results: A total of 91 trials were included, among which were 171,253 participants and 4163 reported cases of heart failure events. As for rankograms, the surface under the cumulative ranking curves (SUCRA) of sodium-glucose co-transporters 2 and thiazolidinediones were 93.4% and 4.3%, respectively, signifying the lowest and highest risk of heart failure, respectively. As for pairwise comparisons in the network, sodium-glucose co-transporters 2 were significantly superior to insulin (OR: 0.75, 95% CI 0.62–0.91), dipeptidyl peptidase 4 inhibitors (OR: 0.68, 95% CI 0.59–0.78), glucagon-like peptide-1 receptor agonists (OR: 0.65, 95% CI 0.54–0.78), and thiazolidinediones (OR: 0.46, 95% CI 0.27–0.77) in terms of heart failure risk. Furthermore, in an exploratory analysis among subjects with underlying heart failure or at risk of heart failure, the superiority of sodium-glucose co-transporters 2 was still significant. Conclusions: In terms of heart failure risk, sodium-glucose co-transporters 2 were the most favorable option among all classes of anti-diabetic medications. [ABSTRACT FROM AUTHOR]