Influence of genetic polymorphisms in cytochrome P450 oxidoreductase on the variability in stable warfarin maintenance dose in Han Chinese.

PURPOSE: The aim of this study was to investigate whether any of the single-nucleotide polymorphisms (SNPs) in the POR gene were significantly associated with CYP activity and expression, and could contribute to the total variability in stable warfarin maintenance doses in Han Chinese. METHODS: A total of 408 patients treated at the First Affiliated Hospital of Sun Yat-Sen University were eligible for the study and had attained a stable warfarin maintenance dose at the start of the investigation. Demographics, warfarin maintenance doses, and concomitant medications were documented. Genomic DNA was extracted from peripheral blood samples and genotyped for ten SNPs (CYP 2C9*2 and *3, CYP4F2 rs2108622, VKORC1 -1639C>T, and potential POR genes of rs10239977, rs3815455, rs41301394, rs56256515, rs1057868, and rs2286823) using the Sequenom MassARRAY genotyping system. RESULTS: A predictive model of warfarin maintenance dose was established and indicated that age, gender, body surface area, aspirin use, CYP2C9*3, CYP4F2 rs2108622, VKORC1 -1639C>T, and POR*37 831-35C>T accounted for 42.4 % of dose variance in patients undergoing anticoagulant treatment. The contribution of POR*37 831-35C>T to warfarin dose variation was only 3.9 %. CONCLUSIONS: For the first time, the SNP POR*37 831-35C>T was confirmed as a minor but statistically significant factor associated with interindividual variation in warfarin maintenance dose in Han Chinese. The POR*37 gene polymorphism should be considered in future algorithms for faster and more reliable achievement of stable warfarin maintenance doses.

Risk of thromboembolic events in atrial fibrillation with chronic kidney disease.

BACKGROUND AND PURPOSE: Chronic kidney disease may increase the risk for ischemic stroke or systemic embolism in patients with nonvalular atrial fibrillation (AF). We conducted a meta-analysis to summarize all published studies to investigate the link between chronic kidney disease and risk of thromboembolic events in AF. METHODS: We performed a literature search using MEDLINE (source PubMed, 1966 to July, 2014) and EMBASE (1980 to July 2014) with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. RESULTS: Eighteen studies involving 538 479 patients and 41 719 incident thromboembolic events were identified. From the pooled analysis, AF patients with estimated glomerular filtration rate <60 mL/min compared with those with estimated glomerular filtration rate ≥60 mL/min experienced a significantly increased risk for developing thromboembolic events (relative risk, 1.62 [95% confidence interval, 1.40-1.87; P<0.001]). The annual rate of thromboembolic events increased by 0.41% (95% confidence interval, 0.17%-0.65%) for a 10 mL/min decrease in renal function. Addition of renal impairment to CHADS2 slightly improved the stroke risk stratification. CONCLUSIONS: Impaired renal function is an independent predictor of stroke or systemic embolism in patients with nonvalvular AF. Consideration of renal function may improve stroke risk stratification in patients with AF.

Current and former smoking and risk for venous thromboembolism: a systematic review and meta-analysis.

BACKGROUND: Smoking is a well-established risk factor for atherosclerotic disease, but its role as an independent risk factor for venous thromboembolism (VTE) remains controversial. We conducted a meta-analysis to summarize all published prospective studies and case-control studies to update the risk for VTE in smokers and determine whether a dose-response relationship exists. METHODS AND FINDINGS: We performed a literature search using MEDLINE (source PubMed, January 1, 1966 to June 15, 2013) and EMBASE (January 1, 1980 to June 15, 2013) with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. Thirty-two observational studies involving 3,966,184 participants and 35,151 VTE events were identified. Compared with never smokers, the overall combined relative risks (RRs) for developing VTE were 1.17 (95% CI 1.09-1.25) for ever smokers, 1.23 (95% CI 1.14-1.33) for current smokers, and 1.10 (95% CI 1.03-1.17) for former smokers, respectively. The risk increased by 10.2% (95% CI 8.6%-11.8%) for every additional ten cigarettes per day smoked or by 6.1% (95% CI 3.8%-8.5%) for every additional ten pack-years. Analysis of 13 studies adjusted for body mass index (BMI) yielded a relatively higher RR (1.30; 95% CI 1.24-1.37) for current smokers. The population attributable fractions of VTE were 8.7% (95% CI 4.8%-12.3%) for ever smoking, 5.8% (95% CI 3.6%-8.2%) for current smoking, and 2.7% (95% CI 0.8%-4.5%) for former smoking. Smoking was associated with an absolute risk increase of 24.3 (95% CI 15.4-26.7) cases per 100,000 person-years. CONCLUSIONS: Cigarette smoking is associated with a slightly increased risk for VTE. BMI appears to be a confounding factor in the risk estimates. The relationship between VTE and smoking has clinical relevance with respect to individual screening, risk factor modification, and the primary and secondary prevention of VTE. Please see later in the article for the Editors' Summary.

[Optimization Method and Case Study of Air Pollution Emission Spatial Pattern].

Few of the current methods of improving air quality, including end-pipe treatment, industrial, energy and transportation structure adjustments, are from the viewpoint of the spatial pattern optimization of pollutant emissions. Therefore, based on factors such as natural environment, human health, pollutant transmission capability, and meteorological diffusion conditions, our research group used the threshold approach, natural breaks, spatial erasure, and other methods to define the layout area suitable for atmospheric pollution sources. Based on these results, the emissions pattern was optimized to achieve air quality improvement. Taking Guangdong Province as an example, we examined the application of the emissions pattern optimization of air quality improvement and atmospheric environment zoning. The results indicate that the first class area of environmental air quality accounts for 9% of total province area, the densely populated area accounts for 3%, the sensitive area of the national air quality monitor stations accounts for 15%, the pollutant accumulation area accounts for 22%, and the layout area suitable for atmospheric pollution sources primarily distributed in the west part of the province accounts for 60%. By shifting the non-thermal power industrial sources into those area, the concentration level of PM2.5 will decrease by 4% at the provincial scale and 10% at the city scale. Emissions pattern optimization has become an innovative aided support technology for the continuous improvement of air quality. In practical applications, it can be combined with energy and industrial structure adjustments, pollution control technology enhancements, and cross-regional prevention and control to formulate the most feasible air quality improvement plan.

CYP4F2 rs2108622: a minor significant genetic factor of warfarin dose in Han Chinese patients with mechanical heart valve replacement.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT * Genetic polymorphisms of VKORC1 and CYP2C9 are known to influence warfarin dosage. * Recent studies among Caucasians showed that polymorphisms of CYP4F2 also play a role in warfarin pharmacogenetics. * The contribution of CYP4F2 variants to the variability inwarfarin dose requirement in Chinese subjects remains to be investigated. WHAT THIS STUDY ADDS * This research was to study the effect of CYP4F2 variants on warfarin requirements in the Han Chinese population. * This study developed a multiple regression model including CYP2C9, VKORC1 3673G>A, CYP4F2 genotypes and age, weight, combination use of amiodarone which could explain 56.1% of the individual variability in warfarin dose CYP4F2 could explain 4% of the variance in warfarin dose. * We found that one novel genotypic polymorphism 5417G>T for Asp36Tyr, which was identified as an important marker of warfarin resistance, was absent in the Han Chinese population in our study. AIMS The objective of this study was to assess the effect of the CYP4F2 on the daily stable warfarin dose requirement in Han Chinese patients with mechanical heart valve replacement (MHVR). METHODS From March 2007 to November 2008, 222 Han Chinese MHVR patients were recruited in our study. VKORC1 3673G>A, 5417G>T, CYP2C9*3 and CYP4F2 rs2108622 were genotyped by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Polymorphisms of VKORC1 9041G>A were detected by direct sequencing. Multiple linear regression analysis was used to investigate the contribution of CYP4F2. RESULTS The CYP4F2 rs2108622 CT/TT group took a significantly higher stable warfarin dose (3.2 mg day(-1)) than the CC group (2.9 mg day(-1), 95% CI 0.2, 1.0, P= 0.033). The multiple linear regression model included VKORC1 3673G>A, CYP2C9, CYP4F2 genotypes and clinical characteristics. The model could explain 56.1% of the variance in stable warfarin dose in Han Chinese patients with MHVR. CYP4F2 contributed about 4% to the variance in the warfarin dose. There was no variation in the SNPs of VKORC1 5417G>T. CONCLUSION CYP4F2 is a minor significant factor of individual variability in the stable warfarin dose in Han Chinese patients with MHVR. The effect of CYP2C9 and VKORC1 genotypes on variability in the stable warfarin dose had also been confirmed.

[Angiotensin-(1-7) reduced postangioplasty vascular fibrosis in abdominal aorta of rabbits].

OBJECTIVE: To explore the effects of Angiotensin (ANG)-(1-7) on postangioplasty fibrotic remodeling and the involvement of TGF-beta/Smad signaling pathway in this process. METHODS: Thirty two healthy New Zealand white rabbits were randomly divided into 4 groups: sham group, control group, ANG-(1-7) group and ANG-(1-7) + A-779 group. Rabbits underwent angioplasty in the abdominal aorta or sham surgery. Subsequently, an osmotic minipump was implanted for saline, ANG-(1-7) (576 microg x kg(-1) x d(-1)) or ANG-(1-7) + A-779 (576 microg x kg(-1) x d(-1)) delivery. Before and after 4 weeks treatment, the levels of ANG II in plasma were measured by ELISA. At week 4, angiography and histomorphometric analysis were performed, mRNA levels of collagen I and III were assayed by RT-PCR and protein levels of TGF-beta1 and Smad2 in local vessel were assayed by Western blot. RESULTS: Following 4 weeks treatment, ANG-(1-7) and ANG-(1-7) + A-779 group displayed a significant elevation in lumen diameter [(4.11 +/- 0.10) mm and (3.34 +/- 0.11) mm vs. (2.88 +/- 0.08) mm, P < 0.05, respectively] and reduction in neointimal thickness [(208 +/- 17) microm and (407 +/- 25) microm vs. (448 +/- 15) microm, P < 0.05, respectively], neointimal area [(0.27 +/- 0.09) mm2 and (0.38 +/- 0.01) mm2 vs. (0.41 +/- 0.02) mm2, P < 0.05, respectively] and restenosis rate [(28.1 +/- 2.7)% and (36.8 +/- 2.2)% vs. (40.1 +/- 2.7)%, P < 0.05, respectively] compared with control group. Collagen I, III mRNA and TGF-beta1, Smad2 protein levels were significantly elevated in control group, ANG-(1-7) group and ANG-(1-7) +A-779 group compared to sham group (P < 0.01 or P < 0.05) and reduced in ANG-(1-7) group compared to control group (all P < 0.05). Co-treatment with A-779 reversed the inhibitory action of ANG-(1-7). Plasma levels of ANG II postangioplasty were similar in control and ANG-(1-7) group and both were significantly higher than preoperation levels. CONCLUSION: ANG-(1-7) attenuates postangioplasty collagen synthesis in rabbits possibly through down-regulating the expression of TGF-beta1 and inhibiting the activation of Smad2 pathway.

[Source Apportionment of Air Pollutants for a Typical Pollution Event in Zhaoqing].

Based on observational data for pollutants and meteorology, this study analyzed the pollution episode that occurred during Dec 17th to 23th in 2018 in Zhaoqing, Guangdong Province, China. Using the source apportionment model CMAQ-ISAM and the hybrid receptor model, the regional contributions to air pollution were examined. The results showed that low-pressure conditions had an adverse effect on the diffusion of pollutants during this pollution episode in Zhaoqing. Prior to the pollution episode, pollutants were mainly derived from Zhaoqing and Qingyuan, accounting for 19.2% and 10.7% of pollutants, respectively. As well as pollutants from Guangdong Province, long-distance transport of pollutants from Jiangxi, Hunan, Hubei, and Shaanxi accounted for approximately 64.5% of the total during the non-pollution period. During the polluted episode, major cities in Pearl River Delta and the eastern part of Guangdong Province contributed more pollutants as a surface high-pressure field moved southward. Zhaoqing, Foshan, Dongguan, Guangzhou, and Huizhou contributed 25.5%, 14.8%, 9.8%, 9.5%, and 5.3% of the pollutants, respectively. Cities in the eastern part of Guangdong Province including Heyuan, Meizhou, Shanwei, Jieyang, Shantou, and Chaozhou contributed 13.7% of the total pollutants. In addition, pollutants from Fujian, Jiangxi, and the Yangtze River Delta accounted for approximately 32.9%. Furthermore, pollutants transported under marine influences were one of the main causes of this pollution episode in Zhaoqing.

[Emission Inventory of Atmospheric Pollutants and VOC Species from Crop Residue Burning in Guangdong Province].

An emission inventory of atmospheric pollutants from crop residue burning in Guangdong for the period 2008-2016 was developed, based on crop yield data. Emissions of species of volatile organic compounds(VOCs)and corresponding ozone formation potential (OFP) in 2016 were also estimated. Results showed that emissions of atmospheric pollutants from crop residue burning in 2013-2016 were lower than in 2008-2012. This was mainly due to the policy of prohibiting open burning of straw and to improvement of rural living standards, which reduced the proportion of straw burning. In 2016, emissions of SO2, NOx, NH3, CH4, EC, OC, NMVOC, CO, and PM2.5 were 2443.7, 16187.9, 6943.8, 29174.4, 3625.5, 14830.7, 65612.6, 591613.9, and 49463.0 t, respectively. Rice straw burning was the main source of pollutants, accounting for about 68.55% of total pollutant emissions. The five municipalities with highest atmospheric pollutant emissions were Zhanjiang, Maoming, Meizhou, Zhaoqing, and Shaoguan, together accounting for about 58.63% of total emissions. The top 10 VOC species for mass-based emissions consisted of ethylene, acetaldehyde, formaldehyde, benzene, ethyne, propylene, ethane, toluene, propane, and propionaldehyde, together contributing 67.91% to total emissions. The top ten OFP-based VOC species were ethylene, formaldehyde, acetaldehyde, propylene, 1-butylene, propionaldehyde, toluene, acrolein, isoprene, and crotonaldehyde, accounting for 80.83% of total OFP.

[Air Quality Subarea Management:A Case Study of Guangdong Province].

To meet the requirements of regional air quality management (AQM), the Air Quality Subarea Management (AQSM) system was proposed. A case study was conducted for Guangdong Province. By using the method of air quality numerical simulation and satellite remote sensing inversion analysis, the key factors were selected from the meteorological simulation field, the pollutant concentration simulation field, and the satellite image interpretation to form the index system for AQSM. On this basis, a hierarchical cluster analysis method was used to divide Guangdong Province into three types of AQSM:Strict Control Subarea, Continuous Improvement Subarea, and Coordinated Development Subarea. It was shown that the Strict Control Subarea, Continuous Improvement Subarea, and Coordinated Development Subarea in Guangdong Province covered 16.3%, 28.0%, and 55.7%, respectively. The Strict Control Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 27.9%, 19.3%, 4.4%, and 12.5%, respectively, and the subarea should implement the most stringent AQM policies to promote air quality improvement. The Continuous Improvement Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 34.4%, 15.8%, 7.8%, and 34.5%, respectively, and the subarea should implement relatively strict AQM policies to ensure sustained and stable standards. The Coordinated Development Subarea in the Pearl River Delta, Eastern Guangdong, Western Guangdong, and Northern Guangdong accounted for 37.7%, 64.9%, 87.8%, and 53.0%, respectively, and the subarea could implement more liberal AQM policies to ensure relatively good air quality. In general, the strict AQM policies in Guangdong Province should be mainly concentrated in the Pearl River Delta region, followed by Northern Guangdong, Eastern Guangdong, and Western Guangdong in order.

[Capacity Simulation Method Based on Regional Transfer Matrix and PM2.5 Concentration Target Constraint].

Atmospheric environmental capacity is an important reference in environmental planning. To meet the PM2.5 standard, a new method is proposed to balance the capacity among cities of Guangdong, with screening of the most unfavorable meteorological year and combining it with the regional transportation calculated by the CAMx-PSAT module. Pollutant overloading and capacity scenarios were also calculated. The results showed that, under the constraints of the cities' annual PM2.5 ≤ 35 µg·m-3, the capacities of SO2, NOx, NH3, and PM2.5 in Guangdong were about 6.8×105 tons, 1.35×106 tons, 4.6×105 tons, and 5.1×105 tons, respectively. Based on the benchmark scenario, SO2 emissions in Guangdong were overloaded by 10%, and the emissions of NOx, NH3, and PM2.5 exceeded by 12%, 9%, and 20%, respectively, compared to those of the capacity scenario. Ranked by the number of overloaded species in Guangdong, the cities of Guangzhou, Foshan, Zhongshan, and Qingyuan were on top. When achieving the capacity scenario, the annual PM2.5 concentration in Guangdong was about 30 µg·m-3, which meets the national secondary ambient air quality standard.

Protective effect of angiotensin-(1-7) against hyperglycaemia-induced injury in H9c2 cardiomyoblast cells via the PI3K̸Akt signaling pathway.

Angiotensin-(1-7) [Ang-(1-7)], a heptapeptide mainly generated from cleavage of AngⅠ and AngⅡ, possesses physiological and pharmacological properties, including anti­inflammatory and antidiabetic properties. Activation of the phosphoinositide 3-kinase and protein kinase B (PI3K̸Akt) signaling pathway has been confirmed to participate in cardioprotection against hyperglycaemia-induced injury. The aim of the present study was to test the hypothesis that Ang-(1-7) protects H9c2 cardiomyoblast cells against high glucose (HG)-induced injury by activating the PI3K̸Akt pathway. To examine this hypothesis, H9c2 cells were treated with 35 mmol/l (mM) glucose (HG) for 24 h to establish a HG-induced cardiomyocyte injury model. The cells were co-treated with 1 µmol/l (µM) Ang-(1-7) and 35 mM glucose. The findings of the present study demonstrated that exposure of H9c2 cells to HG for 24 h markedly induced injury, as evidenced by an increase in the percentage of apoptotic cells, generation of reactive oxygen species and level of inflammatory cytokines, as well as a decline in cell viability and mitochondrial luminosity. These injuries were significantly attenuated by co-treatment of the cells with Ang-(1-7) and HG. In addition, PI3K̸Akt phosphorylation was suppressed by HG treatment, but this effect was abolished when the H9c2 cells were co-treated with Ang-(1-7) and HG. Furthermore, the cardioprotection of Ang-(1-7) against HG-induced injury in H9c2 cardiomyoblasts was highly attenuated in the presence of either D-Ala7-Ang-(1-7) (A-779, an antagonist of the Mas receptor) or LY294002 (an inhibitor of PI3K̸Akt). In conclusion, the present study provided new evidence that Ang-(1-7) protects H9c2 cardiomyoblasts against HG-induced injury by activating the PI3K̸Akt signaling pathway.

[Corrigendum] Protective effect of angiotensin­(1­7) against hyperglycaemia­induced injury in H9c2 cardiomyoblast cells via the PI3K̸Akt signaling pathway.

Subsequently to the publication of this article, the authors have realized that an address affiliation associated with certain of the authors had been omitted. The authors' affiliation information should have appeared as follows (the omitted address affiliation is featured in bold): Yi­Ying Yang1,2*, Xiu­Ting Sun1,2*, Zheng­Xun Li1,2, Wei­Yan Chen3, Xiang Wang4, Mei­Ling Liang5, Hui Shi1,2, Zhi­Sheng Yang1,2 and Wu­Tao Zeng1,2 1Department of Cardiology, The First Affiliated Hospital, Sun Yat­Sen University; 2Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou, Guangdong 510080; 3Intensive Care Unit, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong 510260; 4Department of Cardiology, Laiwu City People's Hospital, Laiwu, Shandong 27110; 5Department of Cardiology, Sun Yat­Sen Cardiovascular Hospital, Shenzhen, Guangdong 518020, P.R. China *Contributed equally. The authors regret this error in the affiliations, and apologize for any inconvenience caused. [the original article was published in the International Journal of Molecular Medicine 41: 1283­1292, 2018; DOI: 10.3892/ijmm.2017.3322].

[Study on up-regulation of the expression of angiotensin-converting enzyme-2 in human umbilical vein endothelial cells by telmisartan].

OBJECTIVE: To investigate the effect of telmisartan on the protein and gene expression of angiotensin-converting enzyme-2 (ACE2) in human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were treated with various concentrations of telmisartan (10(-7), 10(-6) and 10(-5) mol/L) for 24 hours. In a time-control experiment, HUVECs were treated with telmisartan at the final concentration of 10(-6) mol/L for 6, 12 and 24 hours, respectively. In another experiment, HUVECs were treated with PD123319 (10(-6) mol/L) only or combined with same final concentration of telmisartan for 12 hours, respectively. Changes in both protein and gene expression of ACE2 were determined with Western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) technique, respectively. RESULTS: Telmisartan induced a concentration and time dependent increase in both protein and gene expression of ACE2 (P<0.05 or P<0.01). Compared with control group, treatment of HUVECs with telmisartan at the concentration of 10(-7), 10(-6) and 10(-5) mol/L stimulated 1.5-, 2.7- and 4.6-fold increase in the ACE2 protein expression, as well as 1.2-, 2.3- and 4.5-fold increase in its gene expression, respectively. After treatment of HUVECs with telmisartan for 6, 12, and 24 hours at the concentration of 10(-6) mol/L, the ACE2 protein expression increased 1.6-, 2.7- and 4.2-fold, and its gene expression increased 1.3-, 2.3- and 4.0-fold, respectively. Compared with control and telmisartan groups, PD123319 had no effect on both protein and gene expression of ACE2 (P>0.05). CONCLUSION: Telmisartan up-regulates the protein and gene expression of ACE2 in HUVECs in a concentration and time dependent manner. This effect may be mediated via its specific pathway.

Digoxin Use and Adverse Outcomes in Patients With Atrial Fibrillation.

Digoxin has long been used for rate control in atrial fibrillation (AF); its safety remains controversial.We performed a literature search using MEDLINE (source PubMed, January 1, 1966, to July 31, 2015) and EMBASE (January 1, 1980, to July 31, 2015) with no restrictions. Studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the associations of interest were included. Pooled effect estimates were obtained by using random-effects meta-analysis.Twenty-two studies involving 586,594 patients were identified. Patients taking digoxin, as compared with those who took no digoxin, experienced an increased risk of death from any cause (RR: 1.29[95% CI 1.16-1.43]), even after reported adjustment for propensity scores (RR: 1.28[95% CI 1.18-1.39]). The risk of death was increased with patients with or without heart failure (RR: 1.12[95% CI 1.02-1.23] and RR: 1.26[95% CI 1.15-1.29], respectively), and patients taking or not taking beta blockers (RR: 1.17 [95% CI 1.06-1.30] and RR: 1.28 [95% CI 1.08-1.51], respectively). Digoxin use was also associated with increased risk of cardiovascular death (RR: 1.32 [95% CI 1.07-1.64]), arrhythmic death (RR: 1.38 [95% CI 1.07-1.79]), and stroke (RR: 1.20 [95% CI 1.004-1.44]). Digoxin treatment is associated with an absolute risk increase of 19 (95% CI 13-26) additional deaths from any cause per 1000 person-years.Digoxin use is associated with a significant increased risk for death from any cause in patients with AF. This finding suggests a need for reconsideration of present treatment recommendations on use of digoxin in AF.

Effect of angiotensin converting enzyme inhibitor on the calcium transients and calcium handling proteins in ventricular myocytes from rats with heart failure.

BACKGROUND: Chronic heart failure (CHF) is associated with calcium transients and calcium handling proteins. Angiotensin converting enzyme (ACE) inhibitor has been demonstrated to have beneficial effect on CHF. Yet studies addressed to the relationship between ACE inhibitor and calcium transients in CHF are rare. The aim of this study was to investigate the influence of ACE inhibitor (perindopril) on the contractility and calcium transients and calcium handling proteins in ventricular myocytes from rats with experimental heart failure. METHODS: Male Wistar rats were randomized to heart failure group treated with perindopril [CHF-T, 3 mg.kg(-1).d(-1)], heart failure group without treatment (CHF-C) and sham-operated group (PS). Heart failure was induced by abdominal aortic constriction. All groups were further followed up for 12 weeks. Left ventricular myocytes were then isolated. Single cell shortening fraction and [Ca(2+)]i were simultaneously measured by laser scanning confocal microscope under the field stimulation (1.0 Hz). Reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot were performed to evaluate the changes of mRNA and protein of Na(+)-Ca(2+) exchanger (NCX1), sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2) and phospholamban (PLB). RESULTS: The fraction of cell shortening (FS%) and [Ca(2+)]imax (nmol/L) were significantly reduced in group CHF-C compared with group PS (FS%: 7.51 +/- 1.15 vs 13.21 +/- 1.49; [Ca(2+)]i max: 330.85 +/- 50.05 vs 498.16 +/- 14.07; both P < 0.01), and restored at least partially in CHF-T group. In CHF-C group, the left ventricular mRNA of NCX1 and PLB were significantly upregulated in comparing with PS group (RNCX1/beta-Actin: 0.51 +/- 0.12 vs 0.19 +/- 0.06, P < 0.01; RPLB/beta-Actin: 0.26 +/- 0.12 vs 0.20 +/- 0.08, P < 0.05), while SERCA2 mRNA was downregulated (0.48 +/- 0.10 vs 0.80 +/- 0.11, P < 0.01). The mRNA levels of NCX1 and SERCA2 in CHF-T group were between the CHF-C and PS group, and the differences of the latter two groups were significant (all P < 0.05). In CHF-C and CHF-T groups, the protein expression of NCX1 were 1.141 +/- 0.047 and 1.074 +/- 0.081 times of that in PS group respectively (both P < 0.05), and SERCA2 protein levels were 0.803 +/- 0.100 and 0.893 +/- 0.084 times of that in PS group respectively (both P < 0.05). The protein expression of NCX1 and SERCA2 in the CHF-C and CHF-T groups is significantly different (both P < 0.05). CONCLUSION: ACE inhibitor could improve cardiac function of failing heart through directly enhancing the contractility of single cardiomyocyte, and these effects are probably mediated by its roles in preventing the deleterious changes of calcium transients and calcium handling proteins in CHF.

[Angiotensin-(1-7) modulates fibrinolytic imbalance induced by oxidized low-density lipoprotein in cultured human umbilical vein endothelial cells].

OBJECTIVE: To study the effect of angiotensin-(1-7)[Ang-(1-7)]on fibrinolytic imbalance induced by oxidized low- density lipoprotein (ox-LDL) in cultured human umbilical vein endothelial cells (HUVECs). METHOD: Cultured HUVECs were incubated for 24 h in the presence of Ang-(1-7), ox-LDL and A-779 at different concentrations either separately or in combination. The final concentrations of Ang-(1-7) were 10, 100 and 1,000 nmol/L, and those of ox-LDL were 25, 50 and 100 mg protein/L. The final concentration of A-779, an Ang-(1-7) receptor antagonist, was 100 nmol/L. Tissue plasminogen activator (t-PA) and its inhibitor-1(PAI-1) antigen in the medium were determined by enzyme-linked immunosorbent assay (ELISA) and their mRNA levels by reverse transcriptional (RT) PCR. RESULTS: Ox-LDL (25-100 mg protein/L) dose-dependently increased PAI-1 release and up-regulated PAI-1 gene transcription, but decreased t-PA release and down-regulated t-PA gene transcription (P>0.001-0.05). Ang-(1-7) (100-1,000 nmol/L) dose-dependently decreased PAI-1 release and PAI-1 gene transcription (P>0.01-0.05) but had no effect on t-PA release and gene transcription. In the presence of ox-LDL, Ang-(1-7) lowered the increased levels of PAI-1 and PAI-1 mRNA, and elevated the levels of decreased t-PA and t-PA mRNA in the cells (P>0.01-0.05). The effects of Ang-(1-7) could be blocked by A-779. CONCLUSION: Angiotensin-(1-7) effectively modulates the fibrinolytic imbalance induced by ox-LDL via its specific receptor.

Chronic administration of angiotensin-(1-7) attenuates pressure-overload left ventricular hypertrophy and fibrosis in rats.

OBJECTIVE: To test the hypothesis that chronic administration of angiotensin-(1-7) [Ang-(1-7)] attenuates cardiac hypertrophy in rats in vivo. METHODS: Coarctation of the suprarenal abdominal aorta was performed in 41 8-week-old male Sprague Dawley rats. Twenty-four hours after the operation, osmotic minipumps were surgically implanted subcutaneously in the rats, which were randomly divided into 3 groups, including a sham-operation group (n=15) receiving infusion with normal saline, a suprarenal aortic coarctation group (n=12), and a suprarenal aortic coarctation group (n=14) with Ang-(1-7) treatment at the dose of 25 mug x kg(-1) x h(-1). Four weeks later, the systolic and diastolic blood pressures were measured and the left ventricular mass index (LVMI, mg/g) was calculated from the ratio of left ventricular weight to body weight. The concentrations of Ang II in the plasma and myocardium were measured by radioimmunoassay, and myocardial interstitial collagen volume fraction (ICVF) was determined by quantitative morphometry of the sections with Picrosirius red staining using an automated image analyzer. RESULTS: Suprarenal abdominal aortic coarctation induced a significant increase in carotid artery systolic and diastolic blood pressure, heart weight, LVMI, ICVF, and the concentration of Ang II in the myocardium (P<0.01). Chronic administration of Ang-(1-7) attenuated the increase in the heart weight, LVMI, ICVF and left ventricular diastolic end pressure (LVEDP) caused by suprarenal abdominal aortic coarctation (P<0.05). Ang-(1-7) also increased the formerly decreased maximum left ventricular pressure reduction rate (-dP/dt(max)) (P<0.05), but had no effect on blood pressure and the concentration of Ang II in the myocardium. No difference was noted in plasma concentration of Ang II between the 3 groups. CONCLUSIONS: Ang-(1-7) attenuates cardiac hypertrophy and fibrosis and preserved the impaired left ventricular function induced by left ventricular pressure-overload in rats. These effects are not associated with the changes in the concentrations of Ang II in the left ventricular myocardium and plasma.

[Effects of ACE inhibitor on the calcium transient and calcium handling proteins in ventricular myocytes from rats with heart failure].

OBJECTIVE: To investigate the influence of ACE inhibitor (perindopril) on the contractility and calcium transient and calcium handling proteins in ventricular myocytes from rats with experimental heart failure. METHODS: Male Wistar rats were randomized to heart failure group treated with perindopril (CHF-T, 3 mg.kg(-1).d(-1)), heart failure group without treatment (CHF-C) and sham-operated group (PS) after heart failure was induced by constricting abdominal aorta for 16 weeks. All groups were further followed up for 12 weeks. Left ventricular myocytes were isolated, and single cell shortening fraction and [Ca(2+)](i) were simultaneously measured through laser scanning confocal microscope under the field stimulation (1.0 Hz). RT-PCR and Western blot were performed to evaluate the level of mRNA and protein of Na(+)-Ca(2+) exchanger (NCX(1)), sarcoplasmic Ca(2+)-ATPase (SERCA(2)) and phospholamban (PLB). RESULTS: The fraction of cell shortening (FS%) and [Ca(2+)](i max) (nmol/L) were significantly smaller in group CHF-C than group PS (FS%: 7.51 +/- 1.15 vs 13.21 +/- 1.49; [Ca(2+)](i max): 330.85 +/- 50.05 vs 498.16 +/- 14.07; both P < 0.01). And in CHF-T group, FS and [Ca(2+)](i max) were greater than those in CHF-C group. In CHF-C group, the left ventricular mRNA of NCX(1) and PLB were significantly higher than those in PS group (R(NCX)(1)/beta-Actin: 0.51 +/- 0.12 vs 0.19 +/- 0.06, P < 0.01; R(PLB)/beta-Actin: 0.26 +/- 0.12 vs 0.20 +/- 0.08, P = 0.045), yet SERCA(2) mRNA was lower than PS group (0.48 +/- 0.10 vs 0.80 +/- 0.11, P < 0.01). In CHF-T group, the mRNA levels of NCX(1) and SERCA(2) were just in the midst of the CHF-C and PS group, and had statistical significance respectively (all P < 0.05). In CHF - C and CHF - T group, the protein levels of NCX(1) were 1.141 +/- 0.047 and 1.074 +/- 0.081 times PS group, respectively (both P < 0.05), and SERCA(2) protein levels were respectively 0.803 +/- 0.100 and 0.893 +/- 0.084 times as high as in PS group (both P < 0.05). The protein expression of NCX(1) and SERCA(2) were also different between CHF-C and CHF-T groups (both P < 0.05). CONCLUSION: ACE inhibitor could improve cardiac function in CHF through directly enhancing the contractility of single myocardial cell, and these effects were probably mediated by its role in preventing the deleterious changes of calcium transient and calcium handling proteins in CHF.

The Role of Macrolide Antibiotics in Increasing Cardiovascular Risk.

BACKGROUND: Large cohort studies provide conflicting evidence regarding the potential for oral macrolide antibiotics to increase the risk of serious cardiac events. OBJECTIVES: This study performed a meta-analysis to examine the link between macrolides and risk of sudden cardiac death (SCD) or ventricular tachyarrhythmias (VTA), cardiovascular death, and death from any cause. METHODS: We performed a search of published reports by using MEDLINE (January 1, 1966, to April 30, 2015) and EMBASE (January 1, 1980, to April 30, 2015) with no restrictions. Studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the associations of interest were included. RESULTS: Thirty-three studies involving 20,779,963 participants were identified. Patients taking macrolides, compared with those who took no macrolides, experienced an increased risk of developing SCD or VTA (RR: 2.42; 95% CI: 1.61 to 3.63), SCD (RR: 2.52; 95% CI: 1.91 to 3.31), and cardiovascular death (RR: 1.31; 95% CI: 1.06 to 1.62). No association was found between macrolides use and all-cause death or any cardiovascular events. The RRs associated with SCD or VTA were 3.40 for azithromycin, 2.16 for clarithromycin, and 3.61 for erythromycin, respectively. RRs for cardiovascular death were 1.54 for azithromycin and 1.48 for clarithromycin. No association was noted between roxithromycin and adverse cardiac outcomes. Treatment with macrolides is associated with an absolute risk increase of 118.1 additional SCDs or VTA, and 38.2 additional cardiovascular deaths per 1 million treatment courses. CONCLUSIONS: Administration of macrolide antibiotics is associated with increased risk for SCD or VTA and cardiovascular death but not increased all-cause mortality.

More favorable response to cardiac resynchronization therapy in women than in men.

BACKGROUND: Data on sex difference in response to cardiac resynchronization therapy (CRT) remain controversial. We conducted a meta-analysis to summarize all published studies to determine whether sex-based differences in response to CRT exist. METHODS AND RESULTS: We performed a literature search using MEDLINE (source PubMed; January 1966 to March 2014) and EMBASE (January 1980 to March 2014) with no restrictions. Pooled effect estimates were obtained by using random-effects meta-analysis. Seventy-two studies involving 33 434 patients were identified. Overall, female patients had better outcomes from CRT compared with male patients, with a significant 33% reduction in the risk of death from any cause (hazard ratio, 0.67; 95% confidence interval, 0.61-0.74; P<0.001), 20% reduction in death or hospitalization for heart failure (hazard ratio, 0.80; 95% confidence interval, 0.71-0.90; P<0.001), 41% reduction in cardiac death (hazard ratio, 0.59; 95% confidence interval, 0.42-0.84; P<0.001), and 41% reduction in ventricular arrhythmias or sudden cardiac death (hazard ratio, 0.59; 95% confidence interval, 0.49-0.70; P<0.001). These more favorable responses to CRT in women were consistently associated with greater echocardiographic evidence of reverse cardiac remodeling in women than in men. CONCLUSIONS: Women obtained greater reductions in the risk of death from any cause, cardiac cause, death or hospitalization for heart failure, and ventricular arrhythmias or sudden cardiac death with CRT therapy compared with men, with consistently greater echocardiographic evidence of reverse cardiac remodeling in women than in men. Further studies are needed to investigate the exact reasons for these results and determine whether indications for CRT in women should be different from men.