Statins and influenza mortality: systematic review and meta-analysis

Background

Due to their anti-inflammatory properties, it has been suggested that the use of statins could influence the evolution of influenza virus infection.

Objective

To evaluate the effect of statin therapy on mortality from influenza.

Material and methods

A meta-analysis that included studies evaluating the use of statins in patients with influenza and reporting data on mortality, after searching the PubMed/MEDLINE, Embase, and Cochrane Controlled Trials databases, was performed. A random effects model was applied. The risk of bias was analyzed and a sensitivity analysis was performed.

Results

Eight studies (10 independent cohorts), which included a total of 2,390,730 patients, were identified and eligible for analysis. A total of 1,146,995 subjects analyzed received statins, while 1,243,735 subjects were part of the control group. Statin therapy was associated with lower mortality (OR: 0.66; 95% CI: 0.51–0.85). The sensitivity analysis showed that the results were robust.

Conclusions

Our data suggest that, in a population with influenza, the use of statins was associated with a significant reduction in mortality. These results must be confirmed in future clinical trials.

Funding Acknowledgement

Type of funding sources: None.

Non-statin lipid-lowering therapy in coronary atherosclerosis regression: a meta-analysis and meta-regression

Introduction

Several studies have investigated the association between non-statin lipid-lowering therapy and regression of atherosclerosis. However, the studies were mostly small and their results were not always robust.

Objectives

(1) to define if a dual lipid-lowering therapy (statin ± non-statin drugs) is associated with coronary atherosclerosis regression, estimated by intravascular ultrasound (IVUS); (2) to assess the association between dual lipid-lowering-induced changes in LDL-C and non-HDL-C levels and atherosclerosis regression.

Methods

We performed a meta-analysis including trials of non-statin lipid-lowering therapy, reporting C-LDL, non-HDL-C and total atheroma volume (TAV) with a minimum of 6 months of follow-up. The primary endpoint was defined as the change in TAV measured from baseline to follow-up, comparing groups of subjects on statins alone versus combination of statin and non-statin drugs. The random-effects model and meta-regression were performed.

Results

Eight eligible trials of non-statin lipid-lowering drugs (1759 patients) were included. Overall, the dual lipid-lowering therapy was associated with a significant reduction in TAV [−3.5 mm3 (95% CI: −4.5 to −2.6)]; I2=11%]. In the analysis stratified according to the lipid-lowering drug class (ezetimibe or PCSK9 inhibitors), the findings were similar. In a meta-regression, a 10% decrease in LDL-C or non-HDL-C levels, was associated, respectively, with 0.92 mm3 and 1.05 mm3 regressions in TAV.

Conclusion

Our data suggest the addition of ezetimibe or PCSK9 inhibitors to statin therapy results in significantly increased regression of TAV. When the LDL-C and non-HDL-C levels reached were lower, the observed effect was also greater.

Forest Plot by Drugs Group

Funding Acknowledgement

Type of funding source: None

Bicuspid aortic valve: prompt identification of high-risk groups in a heterogeneous disease

Background

Bicuspid aortic valve (BAV) is a congenital heart disease that can be associated with aortic and/or valve complications. Although most BAV are predisposed to progressive calcification, little is known on variables related to significant valvular dysfunction. BAV is a heterogeneous disease, therefore it is important to identify high-risk groups for a closer follow- up and timely intervention.

Objective

Identify the main determinants of primary cardiovascular events (aortic valve replacement, aortic surgery and death) in a cohort of adults with BAV.

Methods

We included 325 consecutive patients with non-syndromatic BAV (2010–2019) referred to our hospital (3rd level). Clinical information was prospectively collected. All patients underwent serial echocardiograms and Cardiac CT was available in 125 patients (38%). We performed univariate and multivariate analyses and Kaplan-Meyer survival analysis with log-rank test. A p-value <0.05 was considered significant.

Results

325 patients (44.4±15.3 years, 73% men), right–left coronary cusp fusion (RL) in 79%,and presence of raphe in 77%. 100 patients (31.2%) had significant aortic valve dysfunction and 103 (31.7%) had aortic dialatation (>40mm) at the onset of the follow-up. Twenty-nine patients required cardiac surgery (8.9%, mainly symptomatic severe aortic stenosis with aortic valve replacement)and 3 died (1%) during a follow-up of 6.3±1.2 years. Patients with at least 2 of the following determinants at baseline: aortic valve prolapse, aortic valve calcification >1, age >50 years and/or aorta >45mm had higher risk of major cardiovascular events during follow-up (Chi2 for log rank test=27,229 p=0,000005).

Conclusions

In this study population of young adults with BAV we observed a high incidence of events related to the BAV. Age>50 years, aortic valve calcification, aortic valve prolapse and aortic dilatation were independently associated with primary cardiac events. Despite significant BAV heterogeneity, the identification of risk factors may help to stratify the risk of valvular dysfunction, aortic dilatation and major cardiovascular events.

BAV: Risk factors for cardiac surgery

Funding Acknowledgement

Type of funding source: None

Role of colchicine in stroke prevention: an updated meta-analysis

Background

Colchicine is a microtubule inhibitor with anti-inflammatory proprieties. As the body and quality of evidence regarding the efficacy of colchicine for cardiovascular prevention is controversial, the aims of this study was to evaluate the effect of colchicine therapy on vascular events.

Methods

A meta-analysis was performed of randomized controlled clinical trials of colchicine on high cardiovascular risk populations, reporting data from stroke, myocardial infarction, cardiovascular mortality and all-cause mortality, after searching the PubMed/MEDLINE, Embase and Cochrane Controlled Trials databases. A random-effects meta-analysis model was then applied.

Results

Nine eligible trials of colchicine therapy, involving a total of 6630 patients, were considered eligible for analysis (3359 subjects were allocated to receive colchicine while 3271 subjects were allocated to the respective control arms). The stroke incidence was lower in the colchicine group compared with placebo arm (OR, 0.33; 95% CI, 0.15–0.70; six studies evaluated). We did not find a significant reduction in the incidence of myocardial infarction, cardiovascular mortality or all-cause mortality.

Conclusion

Our data suggest that in a population with high cardiovascular risk, the use of colchicine results in significantly reduction on stroke risk. Colchicine is an accessible drug that could be successfully utilized for the prevention of atherosclerotic cerebrovascular disease. The tolerability and benefits should be confirmed in ongoing clinical trials.

Forest Plot Primary endpoint

Funding Acknowledgement

Type of funding source: None

Pimozide Alleviates Hyperglycemia in Diet-Induced Obesity by Inhibiting Skeletal Muscle Ketone Oxidation

Perturbations in carbohydrate, lipid, and protein metabolism contribute to obesity-induced type 2 diabetes (T2D), though whether alterations in ketone body metabolism influence T2D pathology is unknown. We report here that activity of the rate-limiting enzyme for ketone body oxidation, succinyl-CoA:3-ketoacid-CoA transferase (SCOT/Oxct1), is increased in muscles of obese mice. We also found that the diphenylbutylpiperidine pimozide, which is approved to suppress tics in individuals with Tourette syndrome, is a SCOT antagonist. Pimozide treatment reversed obesity-induced hyperglycemia in mice, which was phenocopied in mice with muscle-specific Oxct1/SCOT deficiency. These actions were dependent on pyruvate dehydrogenase (PDH/Pdha1) activity, the rate-limiting enzyme of glucose oxidation, as pimozide failed to alleviate hyperglycemia in obese mice with a muscle-specific Pdha1/PDH deficiency. This work defines a fundamental contribution of enhanced ketone body oxidation to the pathology of obesity-induced T2D, while suggesting pharmacological SCOT inhibition as a new class of anti-diabetes therapy.

P811 More than aortic measurements: evaluation with TTE and angioCT in bicuspid aortic valve yields useful information about valvular compromise

Background

2D transthoracic echocardiogram (TTE) is the technique of choice in the diagnosis of bicuspid aortic valve (BAV). Computed tomography (CT) is widely used in BAV to measure aortic diameters. However, in some cases CT or magnetic resonance (MRI) can add important information to TTE regarding valvular degeneration and morphotype.

We designed the present prospective study to determine the agreement between TTE and gated CT in the assessment of aortic valve morphology, fibrosis, calcification and measurements of thoracic aorta. We also aimed to analyze the utility of CT in the evaluation of BAV patients, in addition to aortic measurements.

Methods

We included 30 consecutive patients with BAV (mean age 45 ± 15.7 years ; 73.3% men) who underwent both TTE and ECG-gated cardiac and aortic CT for valvular and aortic assessment in a follow-up protocol with a time interval between TTE and CT of 4 ± 2.6 months.

We performed measurements of thoracic aorta at 6 levels (annulus, Valsalva sinus: VS, sinotubular junction, ascendent, arch and isthmus) with both techniques following guideline recommendations blinded to the results of the other technique.

Several measurements of VS were performed in short-axis view (double-oblique method) (maximal diameter perpendicular to the valve opening, sinus to sinus, raphe to sinus, commissure to commissure) at systole and diastole with CT.

Valve phenotype, presence of raphe, calcification scoring, aortic valve prolapse and fibrosis were also determined with both techniques and maximum aortic diameters were compared. An indexed aortic diameter > 21 mm/m2 was considered as aortic dilation and assimetryc root was defined when differences between CT measurements were ≥5mm.

Results

In 7 patients (23.3%) aortic diameter differences at Sinus by TTE and CT were ≥3mm. Concerning ascending aorta measurements, there was better agreement and only 2 cases (6.6%) showed differences ≥ 3mm.

In 2 patients with severe calcification valve morphology was identified only with CT. There was good agreement between TTE and CT in calcium quantification in patients with valvular calcium score over 2000 AU (n = 5) and in those without calcification. However, TTE failed in identification of valvular fibrosis in 5 patients.

10 patients (30%) had aortic dilatation with CT and 7 according to TTE measurements. The 3 patients that were not identified as dilated in TTE had dilatation at the distal tubular portion.

CT led to identification of coronary anomalies in 5 patients (16.7%), most of them anomalous high origin above the sinotubular junction.

Conclusions

Although TTE is the gold-standard in the diagnosis and follow-up of patients with BAV, CT was useful to confirm aortic measurements and to identify valvular fibrosis, assimetry, coronary anomalies and dilatation at the tubular portion. CT can add important information to TTE regarding valvular morphotype and aortic measurements, although radiation and cost should be evaluated.

Abstract P811 Figure. Calcification agreement TTE and CT

P667Aspirin in primary prevention. Risks and benefits. Up date 2019. A meta-analysis

Objectives

1. Perform an updated meta-analysis on the use of aspirin in primary cardiovascular prevention. 2. Analyze the results by risk.

Methods

This meta-analysis was performed according to the PRISMA guidelines. The primary endpoint was cardiovascular death, AMI, and ischemic stroke. The measures of effect size are expressed as odds ratios. The level of statistical significance was established at 0.05.

Characteristics of the studies Trials Year N Follow-up Risk RTPDABMD 1988 5,139 5.5 Middle PHS 1989 22,071 5 Low HOT 1998 18,790 3.8 Middle TPT 1998 5,085 6.7 Middle PPP 2001 44,95 3.6 Low WHS 2005 39,876 10.1 Low JPAD 2008 2,539 4.4 Low POPADAD 2008 1276 6.7 High AAA 2010 3,350 8.2 Low JPPP 2014 14,464 5 Low ASCEND 2018 15,480 7.4 Middle ARRIVE 2018 12,546 5 Low ASPREE 2018 19,114 4.7 Low RTPDABMD, Randomised trial of prophylactic daily aspirin in British male doctors; PHS, Physicians' Health Study; HOT, Hypertension Optimal Treatment; TPT, Thrombosis Prevention Trial; PPP, Primary Prevention Project; WHS, Women's Health Study; JPAD, Japanese Primary Prevention of Atherosclerosis With Aspirin for Diabetes; POPADAD, Prevention of Progression of Arterial Disease and Diabetes; AAA, Aspirin for Asymptomatic Atherosclerosis; JPPP, Japanese Primary Prevention Project; ASCEND, A Study of Cardiovascular Events in Diabetes; ARRIVE, Aspirin to Reduce Risk of Initial Vascular Events; ASPREE, Aspirin in Reducing Events in the Elderly.

Figure 1

Results

Thirteen works were considered for the analysis (Table 1). A total of 164,225 patients were included, 82,900 in the aspirin arm and 81,325 in the control group. A reduction of the primary endpoint was observed in the AAS group (OR 0.90, 95% CI 0.85–0.94). No differences by risk group (Figure 1). Risk of severe bleeding was significantly higher in patients treated with ASA (OR 1.45, 95% CI 1.34–1.56), this difference was maintained by risk (Figure 1).

Acknowledgement/Funding

None

Empagliflozin Prevents Worsening of Cardiac Function in an Experimental Model of Pressure Overload-Induced Heart Failure

This study sought to determine whether the sodium/glucose cotransporter 2 (SGLT2) inhibitor empagliflozin improved heart failure (HF) outcomes in nondiabetic mice. The EMPA-REG OUTCOME (Empagliflozin, Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients) trial demonstrated that empagliflozin markedly prevented HF and cardiovascular death in subjects with diabetes. However, despite ongoing clinical trials in HF patients without type 2 diabetes, there are no objective and translational data to support an effect of SGLT2 inhibitors on cardiac structure and function, particularly in the absence of diabetes and in the setting of established HF. Male C57Bl/6 mice were subjected to either sham or transverse aortic constriction surgery to induce HF. Following surgery, mice that progressed to HF received either vehicle or empagliflozin for 2 weeks. Cardiac function was then assessed in vivo using echocardiography and ex vivo using isolated working hearts. Although vehicle-treated HF mice experienced a progressive worsening of cardiac function over the 2-week treatment period, this decline was blunted in empagliflozin-treated HF mice. Treatment allocation to empagliflozin resulted in an improvement in cardiac systolic function, with no significant changes in cardiac remodeling or diastolic dysfunction. Moreover, isolated hearts from HF mice treated with empagliflozin displayed significantly improved ex vivo cardiac function compared to those in vehicle-treated controls. Empagliflozin treatment of nondiabetic mice with established HF blunts the decline in cardiac function both in vivo and ex vivo, independent of diabetes. These data provide important basic and translational clues to support the evaluation of SGLT2 inhibitors as a treatment strategy in a broad range of patients with established HF.

Modulations of the Optical Flow Did Not Induce Locomotor Pattern Fluctuations in Treadmill Walking in Man

We report an analysis of gait during human treadmill walking when visual information from the self-displacement velocity was modulated. Removing or sinusoidally modulating the frequency edge information in the optical flow did not induce significant changes in the walking velocity as analyzed using Fast Fourier Transform or in the spatiotemporal gait parameters. While low-frequency fluctuations in displacement speed increased, there was no significant change in locomotor cycle stability. When a constant frequency edge was provided, i.e., when a backward optical flow was added, stride length decreased as compared to the no-optical-flow condition and instantaneous fluctuations in stride amplitude increased. Temporal gait parameters did not change. These partial effects might be better explained by modifications in trunk balance. In humans, modulation of velocity information on self-motion cannot induce unintentional modulation of walking velocity and did not enhance fluctuations in the locomotor pattern. These results argue against the proprioceptive role of sagittal visual-motion information in control of stability of rhythmic leg movement, at least when other proprioceptive feedback sources are available.

Improved Glucose Homeostasis in Obese Mice Treated With Resveratrol Is Associated With Alterations in the Gut Microbiome

Oral administration of resveratrol is able to improve glucose homeostasis in obese individuals. Herein we show that resveratrol ingestion produces taxonomic and predicted functional changes in the gut microbiome of obese mice. In particular, changes in the gut microbiome were characterized by a decreased relative abundance of Turicibacteraceae, Moryella, Lachnospiraceae, and Akkermansia and an increased relative abundance of Bacteroides and Parabacteroides Moreover, fecal transplantation from healthy resveratrol-fed donor mice is sufficient to improve glucose homeostasis in obese mice, suggesting that the resveratrol-mediated changes in the gut microbiome may play an important role in the mechanism of action of resveratrol.

A novel complex I inhibitor protects against hypertension-induced left ventricular hypertrophy

Since left ventricular hypertrophy (LVH) increases the susceptibility for the development of other cardiac conditions, pharmacotherapy that mitigates pathological cardiac remodeling may prove to be beneficial in patients with LVH. Previous work has shown that the activation of the energy-sensing kinase AMP-activated protein kinase (AMPK) can inhibit some of the molecular mechanisms that are involved in LVH. Of interest, metformin activates AMPK through its inhibition of mitochondrial complex I in the electron transport chain and can prevent LVH induced by pressure overload. However, metformin has additional cellular effects unrelated to AMPK activation, raising questions about whether mitochondrial complex I inhibition is sufficient to reduce LVH. Herein, we characterize the cardiac effects of a novel compound (R118), which is a more potent complex I inhibitor than metformin and is thus used at a much lower concentration. We show that R118 activates AMPK in the cardiomyocyte, inhibits multiple signaling pathways involved in LVH, and prevents G_q protein-coupled receptor agonist-induced prohypertrophic signaling. We also show that in vivo administration of R118 prevents LVH in a mouse model of hypertension, suggesting that R118 can directly modulate the response of the cardiomyocyte to stress. Of importance, we also show that while R118 treatment prevents adaptive remodelling in response to elevated afterload, it does so without compromising systolic function, improves myocardial energetics, and prevents a decline in diastolic function in hypertensive mice. Taken together, our data suggest that inhibition of mitochondrial complex I may be worthy of future investigation for the treatment of LVH.NEW & NOTEWORTHY Inhibition of mitochondrial complex I by R118 reduces left ventricular hypertrophy (LVH) and improves myocardial energetics as well as diastolic function without compromising systolic function. Together, these effects demonstrate the therapeutic potential of complex I inhibitors in the treatment of LVH, even in the presence of persistent hypertension.

Cardiomyocyte-specific ablation of CD36 accelerates the progression from compensated cardiac hypertrophy to heart failure

Previous studies have shown that loss of CD36 protects the heart from dysfunction induced by pressure overload in the presence of diet-induced insulin resistance and/or obesity. The beneficial effects of CD36 ablation in this context are mediated by preventing excessive cardiac fatty acid (FA) entry and reducing lipotoxic injury. However, whether or not the loss of CD36 can prevent pressure overload-induced cardiac dysfunction in the absence of chronic exposure to high circulating FAs is presently unknown. To address this, we utilized a tamoxifen-inducible cardiomyocyte-specific CD36 knockout (icCD36KO) mouse and genetically deleted CD36 in adulthood. Control mice (CD36 floxed/floxed mice) and icCD36KO mice were treated with tamoxifen and subsequently subjected to transverse aortic constriction (TAC) surgery to generate pressure overload-induced cardiac hypertrophy. Consistent with CD36 mediating a significant proportion of FA entry into the cardiomyocyte and subsequent FA utilization for ATP production, hearts from icCD36KO mice were metabolically inefficient and displayed signs of energetic stress, including activation of the energetic stress kinase, AMPK. In addition, impaired energetics in icCD36KO mice contributed to a rapid progression from compensated hypertrophy to heart failure. However, icCD36KO mice fed a medium-chain FA diet, whereby medium-chain FAs can enter into the cardiomyocyte independent from CD36, were protected from TAC-induced heart failure. Together these data suggest that limiting FA uptake and partial inhibition of FA oxidation in the heart via CD36 ablation may be detrimental for the compensated hypertrophic heart in the absence of sufficiently elevated circulating FAs to provide an adequate energy source.NEW & NOTEWORTHY Limiting CD36-mediated fatty acid uptake in the setting of obesity and/or insulin resistance protects the heart from cardiac hypertrophy and dysfunction. However, cardiomyocyte-specific CD36 ablation in the absence of elevated circulating fatty acid levels accelerates the progression of pressure overload-induced cardiac hypertrophy to systolic heart failure.

Contribution of limb momentum to power transfer in athletic wheelchair pushing

Pushing capacity is a key parameter in athletic racing wheelchair performance. This study estimated the potential contribution of upper limb momentum to pushing. The question is relevant since it may affect the training strategy adopted by an athlete. A muscle-free Lagrangian dynamic model of the upper limb segments was developed and theoretical predictions of power transfer to the wheelchair were computed during the push phase. Results show that limb momentum capacity for pushing can be in the order of 40J per push cycle at 10m/s, but it varies with the specific pushing range chosen by the athlete. Although use of momentum could certainly help an athlete improve performance, quantifying the actual contribution of limb momentum to pushing is not trivial. A preliminary experimental investigation on an ergometer, along with a simplified model of the upper limb, suggests that momentum is not the sole contributor to power transfer to a wheelchair. Muscles substantially contribute to pushing, even at high speeds. Moreover, an optimal pushing range is challenging to find since it most likely differs if an athlete chooses a limb momentum pushing strategy versus a muscular exertion pushing strategy, or both at the same time. The study emphasizes the importance of controlling pushing range, although one should optimize it while also taking the dynamics of the recovery period into account.

Seasonal gonadal development and age-related maturity patterns of introduced pumpkinseed (Lepomis gibbosus Linnaeus, 1758) in a heated thermal reservoir and an adjacent river reach

Testis and ovarian maturation status, maturity profile and gonado-somatic index (GSI) were assessed in pumpkinseed (Lepomis gibbosus) collected from Mirgenbach, a cooling-water reservoir associated with a nuclear power plant, and from the River Moselle 7km downstream of the reservoir's thermal outflow. Histological investigation indicated that in both sexes, gonadal development of pumpkinseed in the heated reservoir was more advanced than in the cooler Moselle River throughout the breeding season. The histological maturity profile of reservoir males ranked by the advancement of sperm cells was highly correlated with its GSI (rs=0.73, P<0.001). GSI of females in the reservoir increased with the stage at maturity, but GSI was not significantly correlated with total length, age or growth rate of the individual. All sampled individuals of both sexes were mature at age 1 in the heated reservoir, whereas 48% of age 1 males and 57% of age 1 females were not mature in the river. GSI patterns suggest that males in the reservoir adopted one of two reproductive strategies (nesters or cuckolders), whereas no small males with large enough testes to be considered cuckolders were apparent in the river. The warm thermal regime of Mirgenbach Reservoir led to precocial maturity, early season reproduction, and the greater prevalence of apparent cuckolder males than would normally occur in this climatic zone.

A rare missense mutation in CHRNA4 associates with smoking behavior and its consequences

Using Icelandic whole-genome sequence data and an imputation approach we searched for rare sequence variants in CHRNA4 and tested them for association with nicotine dependence. We show that carriers of a rare missense variant (allele frequency=0.24%) within CHRNA4, encoding an R336C substitution, have greater risk of nicotine addiction than non-carriers as assessed by the Fagerstrom Test for Nicotine Dependence (P=1.2 × 10(-4)). The variant also confers risk of several serious smoking-related diseases previously shown to be associated with the D398N substitution in CHRNA5. We observed odds ratios (ORs) of 1.7-2.3 for lung cancer (LC; P=4.0 × 10(-4)), chronic obstructive pulmonary disease (COPD; P=9.3 × 10(-4)), peripheral artery disease (PAD; P=0.090) and abdominal aortic aneurysms (AAAs; P=0.12), and the variant associates strongly with the early-onset forms of LC (OR=4.49, P=2.2 × 10(-4)), COPD (OR=3.22, P=2.9 × 10(-4)), PAD (OR=3.47, P=9.2 × 10(-3)) and AAA (OR=6.44, P=6.3 × 10(-3)). Joint analysis of the four smoking-related diseases reveals significant association (P=6.8 × 10(-5)), particularly for early-onset cases (P=2.1 × 10(-7)). Our results are in agreement with functional studies showing that the human α4β2 isoform of the channel containing R336C has less sensitivity for its agonists than the wild-type form following nicotine incubation.

Normalization of cardiac substrate utilization and left ventricular hypertrophy precede functional recovery in heart failure regression

AIMS

Impaired cardiac substrate metabolism plays an important role in heart failure (HF) pathogenesis. Since many of these metabolic changes occur at the transcriptional level of metabolic enzymes, it is possible that this loss of metabolic flexibility is permanent and thus contributes to worsening cardiac function and/or prevents the full regression of HF upon treatment. However, despite the importance of cardiac energetics in HF, it remains unclear whether these metabolic changes can be normalized. In the current study, we investigated whether a reversal of an elevated aortic afterload in mice with severe HF would result in the recovery of cardiac function, substrate metabolism, and transcriptional reprogramming as well as determined the temporal relationship of these changes.

METHODS AND RESULTS

Male C57Bl/6 mice were subjected to either Sham or transverse aortic constriction (TAC) surgery to induce HF. After HF development, mice with severe HF (% ejection fraction < 30) underwent a second surgery to remove the aortic constriction (debanding, DB). Three weeks following DB, there was a near complete recovery of systolic and diastolic function, and gene expression of several markers for hypertrophy/HF were returned to values observed in healthy controls. Interestingly, pressure-overload-induced left ventricular hypertrophy (LVH) and cardiac substrate metabolism were restored at 1-week post-DB, which preceded functional recovery.

CONCLUSIONS

The regression of severe HF is associated with early and dramatic improvements in cardiac energy metabolism and LVH normalization that precede restored cardiac function, suggesting that metabolic and structural improvements may be critical determinants for functional recovery.

Resveratrol treatment of mice with pressure-overload-induced heart failure improves diastolic function and cardiac energy metabolism

BACKGROUND

Although resveratrol has multiple beneficial cardiovascular effects, whether resveratrol can be used for the treatment and management of heart failure (HF) remains unclear. In the current study, we determined whether resveratrol treatment of mice with established HF could lessen the detrimental phenotype associated with pressure-overload-induced HF and identified physiological and molecular mechanisms contributing to this.

METHODS AND RESULTS

C57Bl/6 mice were subjected to either sham or transverse aortic constriction surgery to induce HF. Three weeks post surgery, a cohort of mice with established HF (% ejection fraction <45) was administered resveratrol (≈320 mg/kg per day). Despite a lack of improvement in ejection fraction, resveratrol treatment significantly increased median survival of mice with HF, lessened cardiac fibrosis, reduced gene expression of several disease markers for hypertrophy and extracellular matrix remodeling that were upregulated in HF, promoted beneficial remodeling, and improved diastolic function. Resveratrol treatment of mice with established HF also restored the levels of mitochondrial oxidative phosphorylation complexes, restored cardiac AMP-activated protein kinase activation, and improved myocardial insulin sensitivity to promote glucose metabolism and significantly improved myocardial energetic status. Finally, noncardiac symptoms of HF, such as peripheral insulin sensitivity, vascular function, and physical activity, were improved with resveratrol treatment.

CONCLUSIONS

Resveratrol treatment of mice with established HF lessens the severity of the HF phenotype by lessening cardiac fibrosis, improving molecular and structural remodeling of the heart, and enhancing diastolic function, vascular function, and energy metabolism.

AMPK-dependent inhibitory phosphorylation of ACC is not essential for maintaining myocardial fatty acid oxidation

RATIONALE

The energy sensor AMP-activated protein kinases (AMPK) is thought to play an important role in regulating myocardial fatty acid oxidation (FAO) via its phosphorylation and inactivation of acetyl coenzyme A carboxylase (ACC). However, studies supporting this have not directly assessed whether the maintenance of FAO rates and subsequent cardiac function requires AMPK-dependent inhibitory phosphorylation of ACC.

OBJECTIVE

To determine whether preventing AMPK-mediated inactivation of ACC influences myocardial FAO or function.

METHODS AND RESULTS

A double knock-in (DKI) mouse (ACC-DKI) model was generated in which the AMPK phosphorylation sites Ser79 on ACC1 and Ser221 (Ser212 mouse) on ACC2 were mutated to prevent AMPK-dependent inhibitory phosphorylation of ACC. Hearts from ACC-DKI mice displayed a complete loss of ACC phosphorylation at the AMPK phosphorylation sites. Despite the inability of AMPK to regulate ACC activity, hearts from ACC-DKI mice displayed normal basal AMPK activation and cardiac function at both standard and elevated workloads. In agreement with the inability of AMPK in hearts from ACC-DKI mice to phosphorylate and inhibit ACC, there was a significant increase in cardiac malonyl-CoA content compared with wild-type mice. However, cardiac FAO rates were comparable between wild-type and ACC-DKI mice at baseline, during elevated workloads, and after a more stressful condition of myocardial ischemia that is known to robustly activate AMPK.

CONCLUSIONS

Our findings show AMPK-dependent inactivation of ACC is not essential for the control of myocardial FAO and subsequent cardiac function during a variety of conditions involving AMPK-independent and AMPK-dependent metabolic adaptations.

Enhanced recovery from ischemia-reperfusion injury in PI3Kα dominant negative hearts: investigating the role of alternate PI3K isoforms, increased glucose oxidation and MAPK signaling

Classical ischemia-reperfusion (IR) preconditioning relies on phosphatidylinositol 3-kinase (PI3K) for protective signaling. Surprisingly, inhibition of PI3Kα activity using a dominant negative (DN) strategy protected the murine heart from IR injury. It has been proposed that increased signaling through PI3Kγ may contribute to the improved recovery of PI3KαDN hearts following IR. To investigate the mechanism by which PI3KαDN hearts are protected from IR injury, we created a double mutant (PI3KDM) model by crossing p110γ(-/-) (PI3KγKO) with cardiac-specific PI3KαDN mice. The PI3KDM model has morphological and hemodynamic features that are characteristic of both PI3Kγ(-/-) and PI3KαDN mice. Interestingly, when subjected to IR using ex vivo Langendorff perfusion, PI3KDM hearts showed significantly enhanced functional recovery when compared to wildtype (WT) hearts. However, signaling downstream of PI3K through Akt and GSK3β, which has been associated with IR protection, was reduced in PI3KDM hearts. Using ex vivo working heart perfusion, we found no difference in functional recovery after IR between PI3KDM and PI3KαDN; also, glucose oxidation rates were significantly increased in PI3KαDN hearts when compared to WT, and this metabolic shift has been associated with enhanced IR recovery. However, we found that PI3KαDN hearts still had enhanced recovery when perfused exclusively with fatty acids (FA). We then investigated parallel signaling pathways, and found that mitogen-activated protein kinase signaling was increased in PI3KαDN hearts, possibly through the inhibition of negative feedback loops downstream of PI3Kα.

Novel O-palmitolylated beta-E1 subunit of pyruvate dehydrogenase is phosphorylated during ischemia/reperfusion injury

BACKGROUND

During and following myocardial ischemia, glucose oxidation rates are low and fatty acids dominate as a source of oxidative metabolism. This metabolic phenotype is associated with contractile dysfunction during reperfusion. To determine the mechanism of this reliance on fatty acid oxidation as a source of ATP generation, a functional proteomics approach was utilized.

RESULTS

2-D gel electrophoresis of mitochondria from working rat hearts subjected to 25 minutes of global no flow ischemia followed by 40 minutes of aerobic reperfusion identified 32 changes in protein abundance compared to aerobic controls. Of the five proteins with the greatest change in abundance, two were increased (long chain acyl-coenzyme A dehydrogenase (48 +/- 1 versus 39 +/- 3 arbitrary units, n = 3, P < 0.05) and alpha subunit of ATP synthase (189 +/- 15 versus 113 +/- 23 arbitrary units, n = 3, P < 0.05)), while two were decreased (24 kDa subunit of NADH-ubiquinone oxidoreductase (94 +/- 7 versus 127 +/- 9 arbitrary units, n = 3, P < 0.05) and D subunit of ATP synthase (230 +/- 11 versus 368 +/- 47 arbitrary units, n = 3, P < 05)). Two forms of pyruvate dehydrogenase betaE1 subunit, the rate-limiting enzyme for glucose oxidation, were also identified. The protein level of the more acidic form of pyruvate dehydrogenase was reduced during reperfusion (37 +/- 4 versus 56 +/- 7 arbitrary units, n = 3, P < 05), while the more basic form remained unchanged. The more acidic isoform was found to be O-palmitoylated, while both isoforms exhibited ischemia/reperfusion-induced phosphorylation. In silico analysis identified the putative kinases as the insulin receptor kinase for the more basic form and protein kinase Czeta or protein kinase A for the more acidic form. These modifications of pyruvate dehydrogenase are associated with a 35% decrease in glucose oxidation during reperfusion.

CONCLUSIONS

Cardiac ischemia/reperfusion induces significant changes to a number of metabolic proteins of the mitochondrial proteome. In particular, ischemia/reperfusion induced the post-translational modification of pyruvate dehydrogenase, the rate-limiting step of glucose oxidation, which is associated with a 35% decrease in glucose oxidation during reperfusion. Therefore these post-translational modifications may have important implications in the regulation of myocardial energy metabolism.

Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France

Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2-620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L.

CDKN2A mutations and melanoma risk in the Icelandic population

BACKGROUND

Germline CDKN2A mutations have been observed in 20-40% of high risk, melanoma prone families; however, little is known about their prevalence in population based series of melanoma cases and controls.

METHODS

We resequenced the CDKN2A gene, including the p14ARF variant and promoter regions, in approximately 703 registry ascertained melanoma cases and 691 population based controls from Iceland, a country in which the incidence of melanoma has increased rapidly.

RESULTS

We identified a novel germline variant, G89D, that was strongly associated with increased melanoma risk and appeared to be an Icelandic founder mutation. The G89D variant was present in about 2% of Icelandic invasive cutaneous malignant melanoma cases. Relatives of affected G89D carriers were at significantly increased risk of melanoma, head and neck cancers, and pancreatic carcinoma compared to relatives of other melanoma patients. Nineteen other germline variants were identified, but none conferred an unequivocal risk of melanoma.

CONCLUSIONS

This population based study of Icelandic melanoma cases and controls showed a frequency of disease related CDKN2A mutant alleles ranging from 0.7% to 1.0%, thus expanding our knowledge about the frequency of CDKN2A mutations in different populations. In contrast to North America and Australia where a broad spectrum of mutations was observed at a similar frequency, in Iceland, functional CDKN2A mutations consist of only one or two different variants. Additional genetic and/or environmental factors are likely critical for explaining the high incidence rates for melanoma in Iceland. This study adds to the geographic regions for which population based estimates of CDKN2A mutation frequencies are available.

[Episiotomy and prevention of perineal and pelvic floor injuries]

OBJECTIVES

The objective of this review was to assess the efficacy of episiotomy to prevent severe perineal tears, urinary incontinence, faecal incontinence and genital prolapse.

MATERIAL AND METHODS

A systematic review on Medline database was performed between 1980 and 2005. One hundred seventy seven articles were selected. Trial quality was assessed on the following parameters: design (prospective, randomized, meta-analysis), sample size (>50) and relevant results. Finally, 43 articles were analysed.

RESULTS

The routine use of episiotomy did not prevent severe perineal tears. It decreased the risk of moderate anterior perineal lacerations. The risk of severe perineal tears during episiotomy increased in the following circumstances: primiparity, Asian women, perineal length<or=3cm, forceps or vacuum-assisted deliveries and macrosomia. Relevant studies were consistent in demonstrating no benefit for routine episiotomy to prevent urinary or faecal incontinence or pelvic floor relaxation, even if there is a lack of data concerning long-term effects on pelvic floor support.

CONCLUSION

The routine use of episiotomy to prevent severe perineal tears, urinary incontinence, faecal incontinence and genital prolapse should be abandoned.

Perinatal care regionalization and acceptability by professionals in France

BACKGROUND

For twenty years, most of industrial countries developed recommendations on regionalization of perinatal care. Perinatal regionalization is particularly aimed at improving morbidity and mortality outcomes of low birth weight newborns by transferring pregnant women to the maternity units having a medical or neonatal environment suited to the risks incurred by mothers or babies. Perinatal regionalization cannot be effective without being well accepted by the majority of professionals. The objectives of this study were then to identify professionals'expectations and objections to perinatal regionalisation and to compare them from a professional group to another one.

METHODS

Professionals of 3 French perinatal networks were under consideration: the Rhône, the Auvergne and the Gard-Lozère networks. The study included two stages: 1) a psychosociological qualitative study, based on professionals'interviews, aimed at identifying main concerns of professionals and developing a questionnaire; then 2) an epidemiological quantitative study, using this questionnaire within French networks. In the questionnaire, 8 dimensions explored the professionals'views: constraints related to regulation aspects and to the setting up of maternity units care levels, risk of loss of professionals' competence and prestige, consequences on medical practices, on inter-professional relationship, on work organization and financial aspects, and related to the new role of 'private practice'professionals, legal consequences.

RESULTS

The response rate of the epidemiological study was 80%. The results permitted to construct 8 dimension scores describing the reasons of poor acceptability of regionalization. After taking into account the age, the sex, the network and the juridical status of the institution, the study revealed a significant poorer acceptability of regionalization by most of medical specialty groups (anesthetists, obstetricians, midwives and "private practice" professionals) compared with neonatologists, or by "private" professionals (professionals working in private clinics and "private practice" professionals) compared with professionals working in university or community hospitals. The study described also network setting up conditions related to its functioning.

CONCLUSION

By identifying clearly professionals 'objections and expectations, this study should facilitate improvement in the organization of studied perinatal networks.

[Neonatal consequences of maternal smoking during pregnancy]

In utero tobacco consumption is a serious public health problem in France; it is very frequent and the long term consequences are not only numerous but also misinterpreted by our population. 25 to 29% of women arrive at the end of their pregnancy without stopping smoking and 50% of non smoking mothers live in an environment polluted by tobacco during pregnancy. The authors would like to stress the gravity of this situation. At the maternity hospital in Nîmes, 358 women who gave birth at term and after a normal pregnancy were enrolled in a survey and monitored with thiocyanate for their tobacco consumption. Birth weight, height, and cranial perimeter of the infants were noted at birth. Results confirmed earlier work on this subject: the three variables studied were consistently weakened by the mother's addiction to tobacco. The authors recall previous medical literature on the pathophysiology and other consequences on the brain: such as I.Q. behavior, sudden infant death syndrome, vascular alterations with possible long-term complications, as well as pulmonary alterations on which there has recently been much research. The question is raised as to why this problem is so neglected in our society and what could be done to change this state of affairs.