High-density lipoprotein regulates angiogenesis by long non-coding RNA HDRACA

Normal high-density lipoprotein (nHDL) can induce angiogenesis in healthy individuals. However, HDL from patients with coronary artery disease undergoes various modifications, becomes dysfunctional (dHDL), and loses its ability to promote angiogenesis. Here, we identified a long non-coding RNA, HDRACA, that is involved in the regulation of angiogenesis by HDL. In this study, we showed that nHDL downregulates the expression of HDRACA in endothelial cells by activating WW domain-containing E3 ubiquitin protein ligase 2, which catalyzes the ubiquitination and subsequent degradation of its transcription factor, Kruppel-like factor 5, via sphingosine 1-phosphate (S1P) receptor 1. In contrast, dHDL with lower levels of S1P than nHDL were much less effective in decreasing the expression of HDRACA. HDRACA was able to bind to Ras-interacting protein 1 (RAIN) to hinder the interaction between RAIN and vigilin, which led to an increase in the binding between the vigilin protein and proliferating cell nuclear antigen (PCNA) mRNA, resulting in a decrease in the expression of PCNA and inhibition of angiogenesis. The expression of human HDRACA in a hindlimb ischemia mouse model inhibited the recovery of angiogenesis. Taken together, these findings suggest that HDRACA is involved in the HDL regulation of angiogenesis, which nHDL inhibits the expression of HDRACA to induce angiogenesis, and that dHDL is much less effective in inhibiting HDRACA expression, which provides an explanation for the decreased ability of dHDL to stimulate angiogenesis.

[Associations of all-cause mortality with admission blood pressure variability during multiple hospitalizations in acute decompensated heart failure]

Objective: To investigate whether admission blood pressure (BP) variability during multiple hospitalizations is associated with all-cause mortality independent of baseline BP in acute decompensated heart failure (ADHF). Methods: Patients with ADHF admitted to the Department of Cardiology, The First Affiliated Hospital of Sun Yat-Sen University from September 2013 to December 2017 were retrospectively enrolled. The risk of all-cause mortality associated with indices of BP variability, including mean admission BPs, standard deviation of BP and coefficient of variation of BP during multiple hospitalizations was assessed, using Cox regression model. Results: A total of 1 006 ADHF patients (mean aged (69.3±13.5) years; 411 (40.8%) female; 670 (66.6%) with preserved ejection fraction) were enrolled. During a median follow-up of 1.54 years, 47.0% of patients died. In all ADHF patients, after adjusting for confounding factors, for every 1-standard deviation (SD) increase in SD and coefficient of variation (CV) of systolic BP, the risk of all-cause mortality increased by 10% and 11%, respectively (SD: HR, 1.10, 95%CI, 1.01-1.21, P=0.029, CV: HR, 1.11, 95%CI, 1.02-1.21, P=0.017); for every 1-SD increase in the mean of diastolic BP, the risk of all cause mortality decreased by 25% (HR, 0.75; 95%CI, 0.65-0.87; P<0.001). In ADHF patients with preserved ejection fraction, after accounted for potential confounders, higher SD and CV of admitted systolic and diastolic BP were significantly associated with higher risk of all-cause mortality, regardless of whether confounding factors were adjusted (P≤0.049); After adjusting for confounding factors, the risk of all-cause mortality increased by 18% and 19% for every 1-SD increase in SD and CV of systolic BP, while the risk of all-cause mortality increased by 11% and 15% for every 1-SD increase in SD and CV of diastolic BP. In ADHF patients with reduced ejection fraction, after adjusting for confounding factors, the higher the mean admission systolic BP during multiple hospitalizations, the lower the risk of total mortality (HR, 0.68; 95%CI, 0.47-1.00; P=0.049). Conclusions: In patients with ADHF, independent of baseline BP, BP variability during multiple hospitalizations was strong predictor of all-cause mortality.

Salt restriction and risk of adverse outcomes in heart failure with preserved ejection fraction

Background

The optimal salt restriction in patients with heart failure (HF), especially patients with heart failure with preserved ejection fraction (HFpEF), remains controversial.

Objective

To investigate the associations of cooking salt restriction with risks of clinical outcomes in patients with HFpEF.

Methods

Cox proportional hazards model and subdistribution hazards model were used in this secondary analysis in 1713 participants with HFpEF from the Americas in the TOPCAT trial. Cooking salt score was the sum of self-reported salt added during homemade food preparation. The primary endpoint was a composite of cardiovascular death, HF hospitalisation and aborted cardiac arrest, and secondary outcomes were all-cause death, cardiovascular death and HF hospitalisation.

Results

Compared with patients with cooking salt score 0, patients with cooking salt score >0 had significantly lower risks of the primary endpoint (HR=0.760, 95% CI 0.638 to 0.906, p=0.002) and HF hospitalisation (HR=0.737, 95% CI 0.603 to 0.900, p=0.003), but not all-cause (HR=0.838, 95% CI 0.684 to 1.027, p=0.088) or cardiovascular death (HR=0.782, 95% CI 0.598 to 1.020, p=0.071). Sensitivity analyses using propensity score matching baseline characteristics and in patients who prepared meals mostly at home yielded similar results. Subgroup analysis suggested that the association between overstrict salt restriction and poor outcomes was more predominant in patients aged ≤70 years and of non-white race.

Conclusion

Overstrict cooking salt intake restriction was associated with worse prognosis in patients with HFpEF, and the association seemed to be more predominant in younger and non-white patients. Clinicians should be prudent when giving salt restriction advice to patients with HFpEF.

Diastolic left ventricular function in relation to the retinal microvascular fractal dimension in a Flemish population

Fractal analysis provides a global assessment of vascular networks (e.g., geometric complexity). We examined the association of diastolic left ventricular (LV) function with the retinal microvascular fractal dimension. A lower fractal dimension signifies a sparser retinal microvascular network. In 628 randomly recruited Flemish individuals (51.3% women; mean age, 50.8 years), we measured diastolic LV function by echocardiography and the retinal microvascular fractal dimension by the box-counting method (Singapore I Vessel Assessment software, version 3.6). The left atrial volume index (LAVI), e', E/e' and retinal microvascular fractal dimension averaged (±SD) 24.3 ± 6.2 mL/m², 10.9 ± 3.6 cm/s, 6.96 ± 2.2, and 1.39 ± 0.05, respectively. The LAVI, E, e' and E/e' were associated (P < 0.001) with the retinal microvascular fractal dimension with association sizes (per 1 SD), amounting to -1.49 mL/m² (95% confidence interval, -1.98 to -1.01), 2.57 cm/s (1.31-3.84), 1.34 cm/s (1.07-1.60), and -0.74 (-0.91 to -0.57), respectively. With adjustments applied for potential covariables, the associations of E peak and E/e' with the retinal microvascular fractal dimension remained significant (P ≤ 0.020). Over a median follow-up of 5.3 years, 18 deaths occurred. The crude and adjusted hazard ratios expressing the risk of all-cause mortality associated with a 1-SD increment in the retinal microvascular fractal dimension were 0.36 (0.23-0.57; P < 0.001) and 0.57 (0.34-0.96; P = 0.035), respectively. In the general population, a lower retinal microvascular fractal dimension was associated with greater E/e', a measure of LV filling pressure. These observations can potentially be translated into new strategies for the prevention of diastolic LV dysfunction.

[Contemporary epidemiology and treatment of hospitalized heart failure patients in real clinical practice in China]

Objective: To observe the etiology, comorbidities, clinical features and treatment patterns of hospitalized patients with heart failure (HF) in China. Methods: Data were collected prospectively on hospitalized patients with HF who were enrolled in China Heart Failure Center Registry Study from 169 participating hospitals from January 2017 to August 2018. In this cross-sectional study, patients were stratified by left ventricular ejection fraction (LVEF) category: heart failure with reduced ejection fraction (HFrEF, LVEF<40%); heart failure with mid-ranged ejection fraction (HFmrEF, 40%≤LVEF<50%) and heart failure with preserved ejection fraction (HFpEF, LVEF≥50%). The clinical data were collected, including demographic information, diagnosis, signs, electrocardiogram, echocardiography, laboratory tests, and treatment. Results: A total of 31 356 hospitalized patients with HF were included, 19 072 (60.8%) were males and the average age was (67.9±13.6) years old. The common causes of HF were hypertension (57.2%), coronary heart disease (54.6%), dilated cardiomyopathy (14.7%), valvular heart disease (9.2%). The common complications were atrial fibrillation/atrial flutter (34.1%), diabetes (29.2%), and anemia (26.7%). 32.8% of patients had a history of hospitalization for HF within the previous 12 months. There were 11 034 (35.2%) patients with HFrEF, 6 825 (21.8%) patients with HFmrEF and 13 497 (43.0%) patients with HFpEF. Compared with patients with HFpEF, patients with HFrEF had a lower systolic blood pressure ((124.7±21.1)mmHg(1 mmHg=0.133 kPa) vs. (134.9±22.9)mmHg), faster heart rate ((85±19) beats/minutes vs. (81±19)beats/minutes), and higher percentage of New York Heart Association (NYHA) class Ⅳ, smoking, alcohol, left bundle branch block, and QRS time≥130 ms, and higher levels of blood uric acid, BNP, and NT-proBNP (all P<0.05). Compared with patients with HFmrEF and HFrEF, patients with HFpEF were older, more women, and higher comorbidity burden including hypertension, atrial fibrillation/atrial flutter, anemia and chronic obstructive pulmonary disease (all P<0.05). HFmrEF took a mid-position between HFrEF and HFpEF in age, gender, heart rate, systolic blood pressure, hypertension, atrial fibrillation/atrial flutter, anemia, and chronic obstructive pulmonary disease (all P<0.05). Patients with HFmrEF had the highest proportion of coronary heart disease, myocardial infarction and percutaneous coronary intervention (all P<0.05). During hospitalization, loop diuretics were used in 90.2% of patients, and intravenous inotropics were used in 20.4% of patients. The use of ACEI/ARB/ARNI, β blockers and aldosterone receptor antagonists at discharge were 71.8%, 79.1% and 83.6% in HFrEF and 69.9%, 75.5% and 72.4% in HFmrEF, respectively. The use of digoxin at discharge was 25.3% (HFrEF 36.7%, HFmrEF 23.1%, HFpEF 17.0%). The rates of cardiac resynchronization therapy and implantable cardioverter defibrillator in HFrEF were 2.7% and 2.1%. Conclusions: Among the hospitalized patients with HF in China, coronary heart disease and hypertension are the mostly prevalent causes. HFpEF accounts for a large proportion of hospitalized patients with HF. HFrEF, HFmrEF and HFpEF have different etiology and clinical features. In real-world, there are still large gaps in the effective application of the guideline recommended therapies to HF patients, especially the non-pharmacological therapy option, which needs to be improved further in China.

A novel DPP6 variant in Chinese families causes early repolarization syndrome

Previous studies demonstrated that variants in dipeptidyl aminopeptidase-like protein-6 (DPP6) are involved in idiopathic ventricular fibrillation. However, its role in early repolarization syndrome (ERS) remains largely elusive. The aim of this study is to determine whether the novel DPP6-L747P variant is associated with ERS, and explore the underlying mechanisms. In our study, whole genome sequencing was used to identify a genetic variant in 4 Chinese families with sudden cardiac arrest induced by ERS. Then, wild-type (WT) DPP6 or mutant (c.2240T > C/p.L747P) DPP6 were respectively expressed in HEK293 cells, co-expressed with K_V4.3 and KChIP2. Western blotting, immunofluorescence, and whole-cell patch clamp experiments were performed to reveal possible underlying mechanisms. A novel missense variant (c.2240T > C/p.L747P) in DPP6 was identified in the 4 families. Both DPP6-WT and DPP6-L747P were mainly located on the cell membrane. Compared with DPP6-WT, the intensity of DPP6 protein bands was downregulated in DPP6-L747P. Functional experiments showed that macroscopic currents exhibited an increase in DPP6-L747P, and the current intensity of DPP6-L747P was increased more than that of DPP6-WT (63.1 ± 8.2 pA/pF vs.86.5 ± 15.1 pA/pF at +50 mV, P < 0.05). Compared with DPP6-WT, the slope of the activation curve of DPP6-L747P was slightly decreased (15.49 ± 0.56 mV vs. 13.88 ± 0.54 mV, P < 0.05), the slope of the inactivation curve was increased (13.65 ± 1.57 mV, vs. 24.44 ± 2.79 mV, P < 0.05) and the recovery time constant was significantly reduced (216.81 ± 18.59 ms vs. 102.11 ± 32.03 ms, P < 0.05). In conclusion, we identified a novel missense variant (c.2240T > C/p. L747P) in DPP6 in 4 Chinese families with sudden cardiac arrest induced by ERS. Patch clamp experiments revealed that this variant could generate a gain of function of I_to and affect the potassium current. These results demonstrated that changes caused by the variant may be the underlying mechanisms of malignant arrhythmias in the individuals with ERS.

A nationwide assessment of blood pressure control and the associated factors in Chinese type 2 diabetes mellitus patients

A subgroup analysis of the nationwide, cross-sectional 3B STUDY was performed to understand the current blood pressure (BP) control status and treatment patterns in Chinese diabetes patients as well as to identify factors associated with BP control. The demographic data, anthropometric parameters, and laboratory results were collected from 24 512 type 2 diabetes patients. The BP goal was a systolic BP <130 mm Hg and a diastolic BP <80 mm Hg regardless of a history of hypertension or current antihypertensive treatment. The overall prevalence of hypertension was 59.9% with geographical differences. Among the diabetes patients with hypertension, 76.9% received antihypertensive medicines. Calcium channel blockers (39.3%), angiotensin II receptor antagonists (26.6%), and then β-blockers (14.0%) or angiotensin-converting enzyme inhibitors (13.6%) were frequently used for BP control. Only 17.5% (n = 2658) of diabetes patients with hypertension reached the recommended target BP. Body mass index <24 kg/m² , urban resident, frequent physical activity, good adherence to medication, comorbidity with cardiovascular disease, achieving glycemic goal (HbA1c <7.0%), achieving lipid goal (low-density lipoprotein cholesterol <2.59 mmol/L) were independent factors that predicted achievement of target BP goal. On the contrary, comorbidity with chronic kidney disease predicted failure to achieve target BP goal. Patients who were treated in a cardiology department or lived in the North were more likely to achieve BP goals. A considerable proportion of diabetic patients failed to achieve guideline-recommended BP targets. More aggressive efforts should be made to overcome the diverse barriers and facilitate the optimization of diabetes management.

[The efficiency of 23 G vitrectomy combined with preoperative subtenon injection of triamcinolone acetonide for treatment of retinal detachment associated with choroidal detachment]

Objective: To evaluate the efficiency of 23 G vitrectomy combined with preoperative subtenon injecfion of triamcinolone acetonide for treatment of rhegmatogenous retinal detachment associated with choroidal detachment. Methods: A retrospective analysis. Forty-eight (16 males and 32 females, aged 57.3±13.9) consecutive patients (48 eyes) who were diagnosed with rhegmatogenous retinal detachment associated with choroidal detachment and received 23 G vitrectomy at the Eye Hospital of Wenzhou Medical University during January 2012 and January 2015 were enrolled. Twenty-three eyes were treated with subtenon injection TA 5 d before the planned 23 G vitrectomy (TA group). Twenty-five eyes were treated with dexamethasone 3 to 5 d before the planned vitrectomy (Dex group). Type-B ultrasonic, intraocular pressure, best corrected visual acuity examinations were conducted for all eyes on admission day, preoperatively and at 1 month, 3 month postoperatively, and during the last visit. The rate of reattachment, change of height of choroidal detachment, intraocular pressure, best corrected visual acuity, and the complication of the eyes between the two groups were compared. All patients were followed up at least half a year after the repair surgery. Results: The intraocular pressure of the TA group was higher than the Dex group[(8.58±3.83)mmHg vs. (6.70±2.49)mmHg (1 mmHg=0.133 kPa), (t=2.032)], and the height of choroidal detachment was lower in TA group [0.90(0.00, 3.84)mm vs. 4.03(1.05, 5.38)mm, Z=-2.569, P<0.05]. There is no statistic difference between the reattachment rate of the two groups [95.7%(22/23) vs. 76.0%(19/25), χ(2)=2.304, P=0.129], but it seems it was better in TA group. The best corrected visual acuity results of the last visit was better in TA group than Dex group [(0.91±0.54) vs. (1.25±0.62), t=-2.034, P=0.048]. The rate of hypertention was higher in TA group than Dex group at 1 month, 3 month postoperatively(χ(2)=2.304, 5.648, P<0.05), while there was no statistic difference of hypertention rate during last visit between the two groups (χ(2)=0.006, P=0.941). Conclusions: The treatment of 23 G vitrectomy combined with subtenon injection of triamcinolone acetonide can improve the intraocular pressure, reduce the height of choroidal detachment, and improve the best corrected visual acuity after the surgery, but it may cause heyertenion. (Chin J Ophthalmol, 2018, 54: 252-257).

Association between paced QRS duration and atrial fibrillation after permanent pacemaker implantation: A retrospective observational cohort study

Right ventricular pacing often results in prolonged QRS duration (QRSd) as the result of right ventricular stimulation, and atrial fibrillation (AF) may result. The association of pacing-induced prolonged QRSd and AF in patients with permanent pacemakers is unknown.We selected 180 consecutive patients who underwent pacemaker implantation for complete/advanced atrioventricular block. All of the patients were paced from the right ventricular septum. Electrocardiography recordings were obtained at the beginning and the end of pacemaker implantation. QRSd was measured in all 12 leads. The QRSd variation was calculated by subtracting the preimplantation QRSd from the postimplantation QRSd.The occurrence of AF was observed in 64 (35.56%) patients (follow-up 33.62 ± 21.47 mo). No significant differences in preimplantation QRSd were observed between the AF occurrence and nonoccurrence groups. The QRSd variation in leads V4 (54.22 ± 29.03 vs 42.66 ± 33.79 ms, P = .022), and V6 (64.62 ± 23.16 vs 48.45 ± 34.40 ms, P = .001) differed significantly between the occurrence and nonoccurrence groups. More QRSd variation in lead V6 (P = .005, HR = 1.822, 95% CI 1.174-2.718, interval scale of QRSd was 40 ms) and left atrial diameter (P = .045, HR = 1.042, 95% CI 1.001-1.086) were independent risk factors for AF occurrence. Receiver operating characteristic curve suggested that QRSd variation in lead V6 could predict AF occurrence, especially for patients with long preimplantation QRSd (≥120 ms, area under the curve was 0.826, 95% CI 0.685-0.967).QRSd variation in lead V6 might be positively correlated with postimplantation AF occurrence. In patients with pacemaker implantation, QRSd could be a complementary criterion for optimizing the right ventricular septal pacing site, and smallest QRSd might be worth pursuing.

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.

Effectiveness and Safety of Warfarin in Dialysis Patients With Atrial Fibrillation: A Meta-Analysis of Observational Studies

In routine practice, warfarin is widely used in dialysis patients with atrial fibrillation (AF) for stroke prevention though the ratio of risks to benefits remains unclear. Recent cohort studies investigating the association between warfarin use and the risks of stroke and bleeding in dialysis patients with AF present conflicting results. The objective of this study was to assess the effectiveness and safety of warfarin use in patients with AF undergoing dialysis. Three databases PubMed, EMBASE, and OVID were searched from their inception to August 2015. Observational studies which assessed the ischemic stroke or bleeding risk of warfarin use in dialysis patients with AF were included. Two reviewers independently extracted data and assessed methodological quality based on the Newcastle-Ottawa Scale score. Combined hazard ratios (HRs) and 95% con&filig;dence intervals (CIs) were calculated using the random-effects model and heterogeneity was assessed based on the Cochrane Q-statistic test and the I statistic. Metaregression analyses were performed to explore the source of heterogeneity. A total of 11 eligible studies with 25,407 patients were included in the analysis. Warfarin use, in comparison with no-warfarin use, was not associated with a lower risk for ischemic stroke (HR 0.95, 95% CI 0.66-1.35). Sensitivity analyses found results to be robust. Metaregression analysis showed that demographic feature, clinical characteristics, or study-level variable had no impact of warfarin use on stroke risk. In addition, warfarin use was associated with a 27% higher risk for bleeding (95% CI 1.04-1.54). Overall, warfarin use did not have a significant association with reduced mortality (95% CI 0.96-1.11). It appears that warfarin use is not beneficial in reducing stroke risk, but with a high risk for bleeding in dialysis patients with AF. Randomized trials are needed to determine the risk-benefit ratio of warfarin in dialysis patients with AF.

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.

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.

Endothelin 1 activation of endothelin A receptor/NADPH oxidase pathway and diminished antioxidants critically contribute to endothelial progenitor cell reduction and dysfunction in salt-sensitive hypertension

Circulating endothelial progenitor cells (EPCs) are reduced in hypertension, which inversely correlates with its mortality. Deoxycorticosterone acetate (DOCA)-salt hypertension features elevated endothelin (ET) 1 and oxidative stress. We tested the hypothesis that ET-1 induces EPC dysfunction by elevating oxidative stress through the ET(A)/NADPH oxidase pathway in salt-sensitive hypertension. Both ET(A) and ET(B) receptors were expressed in EPCs, but only ET(A) receptors were significantly increased in EPCs of DOCA-salt rats. EPC number and function were reduced in DOCA-salt rats compared with sham controls, and both were reversed by in vivo blockade of ET(A) receptors or NADPH oxidase. The enzymatic activities of NAPDH oxidase and its subunits gp91(phox), p22(phox), and Rac1 were augmented in EPCs of DOCA-salt rats, with concomitantly decreased antioxidant enzymes manganese superoxide dismutase, copper-zinc superoxide dismutase, and glutathione peroxidase 1. Reactive oxygen species level was elevated in EPCs from DOCA-salt rats, accompanied by increased EPC telomerase inactivation, senescence, and apoptosis, which were rescued by ET(A) or NADPH oxidase blockade. Cell therapy of normal or treated DOCA EPCs, but not untreated DOCA EPCs, significantly increased capillary density and blood perfusion in ischemic hindlimbs of DOCA-salt rats. p53 and Bax/Bcl-2 ratios were increased in EPCs of DOCA-salt rats, which were reversed by ET(A) antagonist, NADPH oxidase inhibitor, or polyethylene glycol-superoxide dismutase. Finally, in ET(B)-deficient rats, plasma ET-1 was elevated, and EPC number and telomerase activity were diminished. These results demonstrate, for the first time, that both ET-1 activation of ET(A)/NADPH oxidase pathway and diminished antioxidants critically contribute to EPC reduction and dysfunction via increased oxidative stress in salt-sensitive hypertension.

Metformin attenuates ventricular hypertrophy by activating the AMP-activated protein kinase-endothelial nitric oxide synthase pathway in rats

1. Metformin is an activator of AMP-activated protein kinase (AMPK). Recent studies suggest that pharmacological activation of AMPK inhibits cardiac hypertrophy. In the present study, we examined whether long-term treatment with metformin could attenuate ventricular hypertrophy in a rat model. The potential involvement of nitric oxide (NO) in the effects of metformin was also investigated. 2. Ventricular hypertrophy was established in rats by transaortic constriction (TAC). Starting 1 week after the TAC procedure, rats were treated with metformin (300 mg/kg per day, p.o.), N(G)-nitro-L-arginine methyl ester (L-NAME; 50 mg/kg per day, p.o.) or both for 8 weeks prior to the assessment of haemodynamic function and cardiac hypertrophy. 3. Cultured cardiomyocytes were used to examine the effects of metformin on the AMPK-endothelial NO synthase (eNOS) pathway. Cells were exposed to angiotensin (Ang) II (10⁻⁶ mol/L) for 24 h under serum-free conditions in the presence or absence of metformin (10⁻³ mol/L), compound C (10⁻⁶ mol/L), L-NAME (10⁻⁶ mol/L) or their combination. The rate of incorporation of [³H]-leucine was determined, western blotting analyses of AMPK-eNOS, neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) were undertaken and the concentration of NO in culture media was determined. 4. Transaortic constriction resulted in significant haemodynamic dysfunction and ventricular hypertrophy. Myocardial fibrosis was also evident. Treatment with metformin improved haemodynamic function and significantly attenuated ventricular hypertrophy. Most of the effects of metformin were abolished by concomitant L-NAME treatment. L-NAME on its own had no effect on haemodynamic function and ventricular hypertrophy in TAC rats. 5. In cardiomyocytes, metformin inhibited AngII-induced protein synthesis, an effect that was suppressed by the AMPK inhibitor compound C or the eNOS inhibitor L-NAME. The improvement in cardiac structure and function following metformin treatment was associated with enhanced phosphorylation of AMPK and eNOS and increased NO production. 6. The findings of the present study indicate that long-term treatment with metformin could attenuate ventricular hypertrophy induced by pressure overload via activation of AMPK and a downstream signalling pathway involving eNOS-NO.

The nonpeptide AVE0991 attenuates myocardial hypertrophy as induced by angiotensin II through downregulation of transforming growth factor-beta1/Smad2 expression

The nonpeptide AVE0991 is expected to be a putative new drug for cardiovascular diseases. However, the mechanisms for the cardioprotective actions of AVE0991 are still not fully understood. We planned to determine whether AVE0991 attenuates the angiotensin II (AngII)-induced myocardial hypertrophy and whether these AVE0991 effects involved transforming growth factor beta1 (TGF-beta1) and Smad2. A rat model of neonatal myocardial hypertrophy was induced by AngII. The AngII group significantly increased in protein content, surface area, and [(3)H]leucine incorporation efficiency by cardiomyocytes, compared to those of the control group (P < 0.01). The AngII group also had elevated TGF-beta1 and Smad2 expression (P < 0.01). These AngII-induced changes were significantly attenuated by AVE0991 in a dose-dependent manner. In our study, these actions of AngII (10(-6) mol/l) were significantly inhibited by both concentrations of AVE0991 (10(-5) mol/l and 10(-7) mol/l). Moreover, the high AVE0991 group had significantly better inhibition of myocardial hypertrophy than the low AVE0991 group. Meanwhile, the beneficial effects of AVE0991 were completely abolished when the cardiomyocytes were pretreated with Ang-(1-7) receptor antagonist A-779 (10(-6) mol/l). These results suggested that AVE0991 prevented AngII-inducing myocardial hypertrophy in a dose-dependent fashion, a process that may be associated with the inhibition of TGF-beta1/Smad2 signaling.

B-type natriuretic peptide attenuates cardiac hypertrophy via the transforming growth factor-ß1/smad7 pathway in vivo and in vitro

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 microg/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 [(3)H] incorporation were measured. Transforming growth factor (TGF)-beta1 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-beta1 and downregulation of smad7 mRNA and protein expression. The in vitro experiments further proved that BNP inhibited cardiac hypertrophy and changes in the TGF-beta1/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-beta1 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.

Rosiglitazone-induced myocardial protection against ischaemia-reperfusion injury is mediated via a phosphatidylinositol 3-kinase/Akt-dependent pathway

1. Rosiglitazone is widely used in the treatment of Type 2 diabetes. However, in recent years it has become evident that the therapeutic effects of peroxisome proliferator-activated receptor gamma ligands reach far beyond their use as insulin sensitizers. Recently, the ability of rosiglitazone pretreatment to induce cardioprotection following ischaemia-reperfusion (I/R) has been well documented; however, the protective mechanisms have not been elucidated. In the present study, examined the role of the phosphatidylinositol 3-kinase (PI3-K)/Akt signalling pathway in rosiglitazone cardioprotection following I/R injury. 2. Mice were pretreated with 3 mg/kg per day rosiglitazone for 14 days before hearts were subjected to ischaemia (30 min) and reperfusion (2 h). Wortmannin (1.4 mg/kg, i.p.), an inhibitor of PI3-K, was administered 10 min prior to myocardial I/R. Then, activation of the PI3-K/Akt/glycogen synthase kinase (GSK)-3alpha signalling pathway was examined. The effects of PI3-K inhibition on rosiglitazone-induced cardioprotection were also evaluated. 3. Compared with control rats, the ratio of infarct size to ischaemic area (area at risk) and the occurrence of sustained ventricular fibrillation in rosiglitazone-pretreated rats was significantly reduced (P < 0.05). Rosiglitazone pretreatment attenuated cardiac apoptosis, as assessed by ELISA to determine cardiomyocyte DNA fragmentation. Rosiglitazone pretreatment significantly increased levels of phosphorylated (p-) Akt and p-GSK-3alpha in the rat myocardium. Pharmacological inhibition of PI3-K by wortmannin markedly abolished the cardioprotection induced by rosiglitazone. 4. These results indicate that rosiglitazone-induced cardioprotection in I/R injury is mediated via a PI3-K/Akt/GSK-3alpha-dependent pathway. The data also suggest that modulation of PI3-K/Akt/GSK-3alpha-dependent signalling pathways may be a viable strategy to reduce myocardial I/R injury.

[Side effects of non-steroidal anti-inflammatory drugs on gastric mucosa and preventive effects of teprenone]

OBJECTIVE

To evaluate the side effects of non-steroidal anti-inflammatory drugs (NSAID) on gastric mucosa, and to study the preventive effects of teprenone in patients.

METHODS

108 patients taking NSAID for more than 3 months with no infection of helicobacter pylori (Hp) were collected. All patients were screened by endoscopy and their upper gastrointestinal symptoms were evaluated. Then, 16 patients with ulcers were excluded and 92 patients were randomly divided into intervention group with teprenone and control group. After follow-up for 3 months, patients were screened again by endoscopy and their upper gastrointestinal symptoms were also evaluated. Specimens of gastric mucosa were studied by PAS dyeing, and Cyclooxygenase (COX) level were evaluated by immunohistochemical technique.

RESULTS

Of patients taking NSAIDs, the erosion was found in 48 (44.4%) patients while 16 (14.8%) were found with peptic ulcers. The damages were improved significantly (Z = -4.96, P = 0.000) in the intervention group with teprenone (n = 45) as compared with control group (n = 47) after follow-up for 3 months. Both the cox-1 level [31.1% (14/45) vs 6.7% (3/45), P = 0.003] and mucus thickness [66.7% (30/45) vs 13.3% (6/45), P= 0.000] also increased in the intervention group as compared with control group. No significant difference was found on COX-2 level between these two groups [28.9% (13/45) vs 31.1% (14/45), P = 0.82].

CONCLUSION

Long-term use of NSAID caused severe damages on gastric and duodenal mucosa; teprenone improved NSAID-related gastric side effects and increased the COX-1 level and mucus thickness.

Long-term activation of adenosine monophosphate-activated protein kinase attenuates pressure-overload-induced cardiac hypertrophy

Recent in vitro studies suggest that adenosine monophosphate (AMP)-activated protein kinase (AMPK) exerts inhibitory effects on cardiac hypertrophy. However, it is unclear whether long-term activation of AMPK will affect cardiac hypertrophy in vivo. In these reports, we investigate the in vivo effects of long-term AMPK activation on cardiac hypertrophy and the related molecular mechanisms. To examine the effects of AMPK activation in the development of pressure overload-induced cardiac hypertrophy, we administered 5-aminoimidazole 1 carboxamide ribonucleoside (AICAR, 0.5 mg/g body wt), a specific activator of AMPK, to rats with transaortic constriction (TAC) for 7 weeks. We found that long-term AMPK activation attenuated cardiac hypertrophy, and improved cardiac function in rats subjected to TAC. Furthermore, long-term AMPK activation attenuated protein synthesis, diminished calcineurin-nuclear factor of activated T cells (NFAT) and nuclear factor kappaB (NF-kappaB) signaling in pressure overload-induced hypertrophic hearts. Our in vitro experiments further proved that activation of AMPK by infection of AdAMPK blocked cardiac hypertrophy and NFAT, NF-kappaB, and MAPK signal pathways. The present study demonstrates for the first time that pharmacological activation of AMPK inhibits cardiac hypertrophy in through blocking signaling transduction pathways that are involved in cardiac growth. It presents a potential therapy strategy to inhibit pathological cardiac hypertrophy by increasing the activity of AMPK.

Effects of 15-deoxy-delta12,14-prostaglandin J2 on cell proliferation and apoptosis in ECV304 endothelial cells

AIM

To investigate the effects of 15-deoxy-delta12,14-prostaglandin J2 (15d-PGJ2) on cell proliferation and apoptosis in ECV304 endothelial cells and related molecular mechanism.

METHODS

MTT, Hoechst33258, TUNEL, Flow cytometry, DNA ladder, RT-PCR, Western blot, and electrophoretic mobility shift assay (EMSA) analysis were employed.

RESULTS

The 15d-PGJ2 induced apoptosis in ECV304 endothelial cells in a dose-dependent manner (the percentage of apoptosis was enhanced from 10.0 %+/-1.3 % to 32.8 %+/-1.6 %), which was accompanied by inhibition of NF-?B and AP-1 DNA binding activity, down-regulation of c-myc, upregulation of Gadd45 and p53, and activation of p38 kinase. However, the expression of p21 was found no significant change.

CONCLUSION

peroxisome proliferator-activated receptor gamma ligand, 15d-PGJ2, can inhibit proliferation and induce apoptosis in ECV304 endothelial cells through different mechanisms.