Jingchao Lu

Statin therapy shortens QTc, QTcd, and improves cardiac function in patients with chronic heart failure

Although some data suggest that statins can improve cardiac mechanical function in some patients with chronic heart failure (CHF), the effects of long-term statin therapy on cardiac electrical instability remain unclear. We performed a randomized perspective analysis of the effects of 10 mg/d (statin group 1, n=40), 20 mg/d (statin group 2, n=38) of atorvastatin and controls (control group, n=41) on corrected QT intervals (QTc), corrected QT dispersion (QTcd) and cardiac function in patients with CHF secondary to coronary artery disease (CAD) for one year. At 6 and 12 months, the statin groups displayed lower QTc and QTcd compared with controls. The changes were becoming more distinct in statin group 2, (P<0.05). In statin groups, the changes of QTc and QTcd were independent of changes of plasma low-density lipoprotein cholesterol and total cholesterol levels, and the decrease of QTcd was correlated with the increase of LVEF within 12 months. Atorvastatin shortens QTc, QTcd and improves cardiac function, and might thereby be parts of the mechanisms which atorvastatin benefited CHF patients secondary to CAD.

ADDITIVE BENEFICIAL EFFECTS OF AMLODIPINE AND ATORVASTATIN IN REVERSING ADVANCED CARDIAC HYPERTROPHY IN ELDERLY SPONTANEOUSLY HYPERTENSIVE RATS

1 Additive beneficial effects on cardiovascular disease have been reported for amlodipine and atorvastatin. However, it is still unclear whether the combination of amlodipine and atorvastatin has additive beneficial effects on the regression of advanced cardiac hypertrophy in hypertension. In the present study, the effects of the drug combination on advanced cardiac hypertrophy were investigated in elderly spontaneously hypertensive rats (SHR). 2 Elderly SHR (36 weeks old) were randomly allocated into four groups of 12: (i) a vehicle‐treated control group; (ii) an amlodipine (10 mg/kg per day)‐treated group; (iii) an atorvastatin (10 mg/kg per day)‐treated group; and (iv) a group treated with a combination of amlodipine and atorvastatin (both at 10 mg/kg per day). Drugs were administered by oral gavage every morning for a period of 12 weeks before hearts were harvested for analysis. 3 Combined administration of amlodipine and atorvastatin significantly suppressed cardiomyocyte hypertrophy, interstitial fibrosis and upregulation of hypertrophic and profibrotic genes, and also improved left ventricular diastolic dysfunction to a greater extent than did amlodipine monotherapy. Further beneficial effects of combination therapy on advanced cardiac hypertrophy were associated with a greater reduction of NADPH oxidase‐mediated increases in cardiac reactive oxygen species (ROS), rather than decreased blood pressure and serum cholesterol levels. 4 To elucidate the underlying molecular mechanisms, we examined cardiovascular NADPH oxidase subunits and found that amlodipine clearly attenuated the expression of p47phox and p40phox and slightly but significantly reduced p22phox and Rac‐1 levels in heart tissue. Combination treatment with amlodipine plus atorvastatin led to a further reduction in p22phox, p47phox and Rac‐1 protein levels compared with amlodipine alone. 5 In conclusion, combined amlodipine and atorvastatin treatment has a greater beneficial effect on advanced cardiac hypertrophy compared with amlodipine monotherapy. The benefits are likely to be related to the additive effects of the drugs on the suppression of NADPH oxidase‐mediated ROS generation.

Amlodipine and atorvastatin improve ventricular hypertrophy and diastolic function via inhibiting TNF-α, IL-1β and NF-κB inflammatory cytokine networks in elderly spontaneously hypertensive rats.

This study aimed to examine the effects of amlodipine and atorvastatin alone or in combination on the regulation of inflammatory cytokines and the underlying mechanisms in elderly spontaneously hypertensive (SH) rats. The level of serum hs-CRP was detected with ELISA. The serum TNF-α and IL-1β levels were assessed by radioimmunity assay (RIA). Cardiac inflammatory cell infiltration was observed by HE staining. The protein levels of TNF-α, IL-1β, of NF-κB P65 and IκBα were detected by immunoblotting. The intracellular localization of NF-κB p65 was observed using immunohistochemistry. Amlodipine or atorvastatin obviously ameliorated the myocardial inflammatory cell infiltration in SH rats, which was further improved by combinatorial treatment with amlodipine and atorvastatin. Either amlodipine or atorvastatin decreased plasma IL-1β content in SH rats, but there was no significant difference when compared with untreated SH rats. However, the combination of amlodipine and atorvastatin significantly decreased plasma IL-1β level in SH rats. Moreover, amlodipine or atorvastatin intervention significantly reduced myocardial TNF-α and IL-1β protein levels in SH rats, which was further suppressed by the combination of amlodipine and atorvastatin. In addition, amlodipine or atorvastatin inhibited the activity of NF-κB signaling in SH rats, which was further suppressed by combinatorial treatment. Furthermore, amlodipine or atorvastatin restored the activity of IκB-α in SH rats, which was enhanced by combinatorial treatment. Our results demonstrated amlodipine and atorvastatin improved ventricular hypertrophy and diastolic function possibly through the intervention of TNF-α, IL-1β, NF-κB/IκB inflammatory cytokine network. Our study suggests that amlodipine combined with atorvastatin may have additive effect on inhibiting inflammatory response.

Amlodipine and atorvastatin improved hypertensive cardiac hypertrophy through regulation of receptor activator of nuclear factor kappa B ligand/receptor activator of nuclear factor kappa B/osteoprotegerin system in spontaneous hypertension rats

The present study aims to study the role of receptor activator of nuclear factor kappa B ligand/receptor activator of nuclear factor kappa B/osteoprotegerin (RANKL/RANK/OPG) system in cardiac hypertrophy in a spontaneous hypertension rat (SHR) model and the effects of amlodipine and atorvastatin intervention. Thirty-six-week-old male SHRs were randomly divided into four groups: 1) SHR control group; 2) amlodipine alone (10 mg/kg/d) group, 3) atorvastatin alone (10 mg/kg/d) group, 4) combination of amlodinpine and atorvastatin (10 mg/kg/d for each) group. Same gender, weight, and age of Wistar-Kyoto (WKY) rats with normal blood pressure were used as normal control. Drugs were administered by oral gavage over 12 weeks. The thicknesses of left ventricle walls, left ventricle weight, and cardiac function were measured by transthoracic echocardiography. Left ventricular pressure and function were assessed by hemodynamic examination. Cardiomyocyte hypertrophy and collagen accumulation in cardiac tissue were measured by hematoxylin and eosin (HE) and Masson staining, respectively. The hydroxyproline content of cardiac tissue was examined by biochemistry technique. RANKL, RANK and OPG mRNA, protein expression and tissue localization were studied by RT-PCR, Immunohistochemistry and Western blot. Treatment with amlodipine or atorvastatin alone significantly decreased left ventricular mass index, cardiomyocyte cross-sectional area and interstitial fibrosis in SHR (each P < 0.05). Moreover, combined amlodipine and atorvastatin treatment induced significant reversal of left ventricular hypertrophy and decreased cardiomyocyte cross-sectional area and interstitial fibrosis in SHR to a greater extent than each agent alone (P < 0.05). Compared with WKY rats, the myocardial expression of RANKL, RANK, and OPG was increased. Both amlodipine and atorvastatin reduced RANKL, RANK, and OPG expression, with the best effects seen with the combination. Based on our results, activation of the RANKL/RANK/OPG system may be an important factor leading to ventricular remodeling in SHR rats. Amlodipine and atorvastatin could improve ventricular remodeling in SHR rats through intervention with the RANKL/RANK/OPG system.

Role of Vitamin C in Cardioprotection of Ischemia/Reperfusion Injury by Activation of Mitochondrial KATP Channel

How to provide effective prevention and treatment of myocardial ischemia/reperfusion (I/R) injury and study of the mechanism underlying I/R injury are hotspots of current research. This study aimed to elucidate the effect and cardioprotective mechanism of vitamin C (VC) on myocardial I/R injury. Our study introduced two different I/R models: I/R in vitro and oxygen-glucose deprivation/recovery (OGD/R) in primary neonatal rat cardiac myocytes. We used the mitochondrial permeability transition pore (mPTP) opener lonidamine (LND) and the mitochondrial KATP (mitoKATP) channel inhibitor 5-hydroxydecanoate (5-HD) to analyze the underlying mechanisms. We found that post-treatment with VC decreased I/R injury in our models. Post-treatment with VC significantly decreased I/R-induced injury, attenuated apoptosis, and maintained the functional integrity of mitochondria via alleviation of Ca(2+) overload, reactive oxygen species burst, inhibition of the opening of mPTP, and prevention of mitochondrial membrane potential (ΔΨm) depolarization. VC post-treatment increased the phosphorylation of Akt and glycogen synthase kinase (GSK)-3β. The present results demonstrate that VC might protect the myocardium from I/R-induced injury by inhibiting the mPTP opening via activation of mitoKATP channels. VC mediates cardioprotection via activation of the phosphatidyl inositol 3-kinase (PI3K)-Akt signaling pathway. These findings may contribute toward the development of novel strategies for clinical cardioprotection against I/R injury.

Cardioprotective effects of single oral dose of nicorandil before selective percutaneous coronary intervention

Objective: Nicorandil, an opener of ATP-sensitive K+ channels, was used to treat angina in patients with coronary artery disease. In this study, we aim to investigate the cardioprotective effects of single oral dose of nicorandil in patients undergoing selective percutaneous coronary intervention (PCI). Methods: One hundred and thirty-eight patients with acute coronary syndrome undergoing PCI from July 2011 to October 2012 were randomly divided into control group (group 1, n=47), 10 mg oral nicorandil group (group 2, n=45), and 20 mg oral nicorandil group (group 3, n=46) about 2 hours before procedure, respectively. Cardiac troponin I (cTnI) levels were determined at 20 ~ 24 hours after PCI. Results: There was a significant difference in the rate of any cTnI elevation among the three groups (group 1: 36.17%, group 2: 20.00%, group 3: 15.22%, p=0.0176). With respect to the frequency of cTnI elevation ≥3 and 5×the upper limit of normal (ULN), there also had statistical difference among the three groups (17.02% in group 1, 8.89% in group 2, and 4.35% in group 3, respectively for cTnI elevation ≥3× ULN, p=0.0428; 12.77% in group 1, 6.67% in group 2, and 2.17% in group 3, respectively, for cTnI elevation ≥5× ULN, p=0.0487). Logistic regression analysis showed that LVEF (OR=0.915, 95% CI=0.853-0.981) and the use of nicorandil (OR=0.516, 95% CI=0.267-0.996) before PCI were independent protective factors of myocardial injury. Conclusion: Single oral dose of nicorandil (10 mg, 20 mg) 2 hours before the PCI procedure could decrease the incidence of peri-procedure myocardial injury and PCI-related myocardial infarction.

Fractional systolic and diastolic pressures act as predictors of coronary artery disease

Aims. This study was designed to determine if fractional systolic/diastolic pressures act as predictors of the extent of coronary artery disease. Patients and methods. A total of 545 consecutive patients (305 men, 240 women, with mean age 54.2 years) were involved in the study. The patients were diagnosed with coronary and non-coronary artery disease confirmed by angiography. Results. 353 patients were confirmed to have coronary artery disease, with 134 cases involving one vessel, 101 two vessels and 118 three vessels. There were significant differences between brachial and ascending aortic systolic blood pressures, fractional systolic blood pressures and fractional diastolic blood pressures in the patients with coronary artery disease compared with patients with non-coronary artery disease. Blood pressure measured in the brachial artery was higher than the pressure measured in the ascending artery. Ascending aortic fractional systolic/diastolic pressures were associated with coronary Gensini score, and were significantly related to the number of diseased vessels. Conclusions. Fractional systolic and diastolic pressures in the ascending aorta were strong predictive factors for the extent of coronary artery disease. Central pressures measured invasively in the ascending aorta were more predictive than peripheral pressures for the evaluation of coronary artery disease.

Amlodipine and Atorvastatin Improved Hypertensive Cardiac Remodeling through Regulation of MMPs/TIMPs in SHR Rats

Background: MMPs/TIMPs system is well known to play important roles in pressure overload-induced cardiac remodeling, and Amlodipine and Atorvastatin have been showed to exert favourable protective effects on cardiovascular disease, however, it is not clear whether Amlodipine and Atorvastatin can improve hypertensive cardiac remodeling and whether the MMPs/TIMPs system is involved. The present study aims to answer these questions. Methods: 36 weeks old male spontaneous hypertension (SHR) rats were randomly divided into four groups: 1). SHR control group, 2). Amlodipine alone (10 mg/kg/d) group, 3). Atorvastatin alone (10 mg/kg/d) group, 4).Combination of Amlodipine and Atorvastatin (10 mg/kg/d for each) group. Same gender, weight and age of Wistar-Kyoto (WKY) rats with normal blood pressure were used as normal control. Drugs were administered by oral gavage over 12 weeks. The blood pressure and left ventricle mass index were measured. Enzyme activity of MMP-2 and MMP-9 was assessed with Gelatin zymography. MMP-2, MMP-9, TIMP-1 and TIMP-2 mRNA and protein expression was studied by RT-PCR and Western blot. Single factor ANOVA and LSD-t test were used in statistical analysis. Results: Treatment with Amlodipine alone or combination with atorvastatin significantly decreased blood pressure, left ventricle mass index in SHR rats (P < 0.05 for both). Compared with WKY rats, the myocardial levels of MMP-2, MMP-9 mRNA, protein and enzyme activity were significantly increased (P<0.05). Amlodipine alone, Atorvastatin alone, and combination of the two all reduced MMP-2 and MMP-9 mRNA, protein and enzyme activity, with the best effects seen in the combination. Compared with WKY rats, the myocardial levels of TIMP-1 mRNA and protein were significantly increased (P<0.05), however, there was no difference in levels of TIMP-2. Neither Amlodipine alone, Atorvastatin alone, nor combination of the two drugs significantly affect the expression of TIMP-1 or TIMP-2. Conclusion: Amlodipine and Atorvastatin could improve ventricular remodeling in SHR rats through intervention with the imbalance of MMP-2/TIMP-2 and MMP-9/TIMP-1 system.

GW24-e2409 The establishment and mechanism of spontaneous calcification of aortic interstitial cells in SD rats

Objectives Aortic valve interstitial cells (AVICs) play a vital role in the development of aortic valve stenosis. The aim of this study is to observe that whether or not AVICs calcified spontaneously and to detect the expression of osteogenic factors in the formation of calcified cell nodules. Methods AVICs were cultured in explant method, calcification were detected by Von Kossa, alizarin red S stain and a calcium assay kit, and expression of osteogenic factors, such as Cbfa1/ OC/BMP-2/BMP-4, were detected by RT-PCR and western-blot analysis at different times. Results AVICs aggregated and formed small cell nodules after 4∼6 day culture, and the number of nodules become more and the diameter is bigger at day 12 than that at day 6. The cell nodules were positive by Von Kossa and alizarin red S stain, which indicated that they were calcified nodules. The statistical analysis indicated that both the content of alizarin red S and calcium at day 12 were higher than that at day 0 and day 6 (F = 106.167, F = 116.379, respectively; P<0.001). The statistic analysis of the osteogenic gene expression indicated that the Cbfa1/OC/ BMP- 4 mRNA were lowest at day 0, higher at day 6 and highest at day 12 (F = 410.106, X2 = 7.200, F = 38.463, respectively; P < 0.005), and BMP-2 mRNA were lowest at day 0, higher at day 6 and day 12 (F = 56.565, P < 0.001). The statistic analysis of the osteogenic protein expression indicated that the BMP-2/4 protein expression were lowest at day 0, higher at day 6 and highest at day 12 (x2 = 7.200, F = 452.482, respectively; P < 0.05). Conclusions AVICs calcified spontaneously with extend culture time, in which the differentiation of AVICs into osteoblasts-like cells may play an important role in the process of calcification.

APOLIPOPROTEIN E SUPPRESSES IL-12 PRODUCTION IN MACROPHAGES

Objectives Accumulation of T cells and macrophages in atherosclerotic plaques and the formation of antibodies directed against plaque proteins suggests that adaptive immunity contributes to the development of atherosclerosis. Apolipoprotein E (apoE) exerts potent anti-inflammatory effects that may contribute to protection against atherosclerosis independent of its role in lipid metabolism. Here, we investigated the expression of pro-inflammatory cytokine interleukin-12 (IL-12) in macrophages of apoE−/− mice and then further explored the molecular mechanisms. Methods In this study, peritoneal macrophages and bone marrow- derived macrophages elicited from wild-type (WT) or apoE knockout (apoE−/−) mice were stimulated with low-dose lipopolysaccharide (LPS), interferon-r (IFN-r) or LPS plus IFN-r for 24 h, followed by collection of culture supernatants for measurement of IL-12 p40 and p70 protein secretion by ELISA. Meanwhile, cells treated with these stimuli for 4 h were used for RNA isolation and IL-12 p35 and p40 mRNA detection by quantitative real-time PCR. Then, we transiently co-transfected a human IL-12 p35 promoter luciferase construct with different amounts of apoE expression vector or PTYB2 vector into THP-1 cells (a human macrophage cell line) by electroporation, followed by measurement of luciferase activity in cell lysates. Results The expression of IL-12 were upregulated to a significantly greater extent in apoE-deficient mice than in WT mice at both the mRNA and protein levels following administration of LPS or LPS plus IFN-r. ApoE suppressed IL-12 p35 promoter in a dose-dependent manner, indicating that apoE-mediated p35 gene suppression is regulated at the level of transcription. Moreover, cells co-transfected with the p35 promoter and the apoE-expressing vector showed decreased promoter activities in response to IFN-r and LPS treatments compared with cells co-transfected with the empty vector, PTYB2, further demonstrating that apoE suppressed IL-12 p35 gene transcription under both basal and inducible conditions. Conclusions Our study reveals that apoE suppresses IL-12 production at the level of transcription in macrophages, this effect may represent a novel anti-inflammatory activity of apoE.