Yin-Yang 1 transcription factor modulates ST2 expression during adverse cardiac remodeling post-myocardial infarction.

BACKGROUND: The cardioprotective effects of metformin remain poorly defined. Interleukin (IL)-33/ST2L signaling is a novel cardioprotective pathway, which is antagonized by the soluble isoform sST2. No data exist about the regulation of ST2 expression. This study aimed to evaluate the pathophysiological implication of Yin-Yang 1 (Yy1) transcription factor in cardiac remodeling and the expression of the soluble ST2 isoform. METHODS AND RESULTS: Myocardial infarction (MI) was induced in Wistar rats randomly receiving metformin or saline solution by permanent ligation of the left anterior coronary artery. In addition, a model of cardiomyocyte "biochemical strain" was used. Metformin administration improved post-MI cardiac remodeling, an effect that was associated with increased IL-33 and reduced sST2 levels in the myocardium. The anti-remodeling effects of metformin were also associated with a decrease in the transcription factor Yy1 intranuclear level and lower levels of phosphorylated HDAC4 within the cytoplasmic space. These effects were also observed in a cardiomyocyte biochemical strain model, where Yy1 silencing or HDAC4 inhibition blocked sST2 production in cardiomyocytes. Metformin blocked the HDAC4 phosphorylation induced by MI, preventing its export from the nucleus to the cytosol. The presence of dephosphorylated HDAC4 in the nucleus acted as a co-repressor of Yy1, repressing sST2 expression. CONCLUSION: The transcription factor Yy1 regulates sST2 expression, and repression of Yy1 by metformin results in lower levels of sST2 that are associated with favorable myocardial remodeling. The manipulation of YY1 or its co-repressor HDAC4 emerge as new targets to modulate ST2/IL33 signaling and prevent adverse cardiac remodeling.

Conformational and thermal characterization of left ventricle remodeling post-myocardial infarction.

Adverse cardiac remodeling after myocardial infarction (MI) causes impaired ventricular function and heart failure. Histopathological characterization is commonly used to detect the location, size and shape of MI sites. However, the information about chemical composition, physical structure and molecular mobility of peri- and infarct zones post-MI is rather limited. The main objective of this work was to explore the spatiotemporal biochemical and biophysical alterations of key cardiac components post-MI. The FTIR spectra of healthy and remote myocardial tissue shows amides A, I, II and III associated with proteins in freeze-died tissue as major absorptions bands. In infarcted myocardium, the spectrum of these main absorptions was deeply altered. FITR evidenced an increase of the amide A band and the distinct feature of the collagen specific absorption band at 1338cm-1 in the infarct area at 21days post-MI. At 21days post-MI, it also appears an important shift of amide I from 1646cm-1 to 1637cm-1 that suggests the predominance of the triple helical conformation in the proteins. The new spectra bands also indicate an increase in proteoglycans, residues of carbohydrates in proteins and polysaccharides in ischemic areas. Thermal analysis indicates a deep increase of unfreezable water/freezable water in peri- and infarcted tissues. In infarcted tissue is evidenced the impairment of myofibrillar proteins thermal profile and the emergence of a new structure. In conclusion, our results indicate a profound evolution of protein secondary structures in association with collagen deposition and reorganization of water involved in the scar maturation of peri- and infarct zones post-MI.

Variable endothelial cell function restoration after initiation of two antiretroviral regimens in HIV-infected individuals.

Background: The effect of ART on endothelial cell function is incompletely characterized. Methods: We performed a 24 week prospective, case-control and comparative pilot study of ART-naive HIV-infected patients who started a darunavir- or rilpivirine-based regimen, matched with non-HIV-infected volunteers, to compare changes at week 24 from baseline in levels of circulating endothelial cells (CECs), endothelial progenitor cells (EPCs) and circulating angiogenic cells, as well as changes in immune-activation markers. Results: The study population comprised 24 HIV-infected patients and 24 non-infected volunteers. Both HIV groups completely suppressed viraemia. HIV-infected patients had higher levels of activation markers than the control group in CD8 T cells at baseline; these decreased after 24 weeks of treatment, but without reaching the levels of the control group. No statistical differences in immune activation were seen between the darunavir and rilpivirine groups. Levels of CECs were higher and levels of EPCs and circulating angiogenic cells were lower in HIV-infected patients than in the control group, although these parameters were similar between the darunavir group and the control group, but not the rilpivirine group, at week 24. An unfavourable association was observed between rilpivirine, age and increased number of CECs. Conclusions: Restoration of circulating levels of EPCs and CECs in darunavir-treated patients was greater than in those treated with rilpivirine, suggesting ongoing endothelial repair mechanisms.

The obesity paradox in heart failure patients with preserved versus reduced ejection fraction: a meta-analysis of individual patient data.

BACKGROUND: In heart failure (HF), obesity, defined as body mass index (BMI) ≥30 kg m(-2), is paradoxically associated with higher survival rates compared with normal-weight patients (the 'obesity paradox'). We sought to determine if the obesity paradox differed by HF subtype (reduced ejection fraction (HF-REF) versus preserved ejection fraction (HF-PEF)). PATIENTS AND METHODS: A sub-analysis of the MAGGIC meta-analysis of patient-level data from 14 HF studies was performed. Subjects were divided into five BMI groups: <22.5, 22.5-24.9 (referent), 25-29.9, 30-34.9 and ≥35 kg m(-2). Cox proportional hazards models adjusted for age, sex, aetiology (ischaemic or non-ischaemic), hypertension, diabetes and baseline blood pressure, stratified by study, were used to examine the independent association between BMI and 3-year total mortality. Analyses were conducted for the overall group and within HF-REF and HF-PEF groups. RESULTS: BMI data were available for 23 967 subjects (mean age, 66.8 years; 32% women; 46% NYHA Class II; 50% Class III) and 5609 (23%) died by 3 years. Obese patients were younger, more likely to receive cardiovascular (CV) drug treatment, and had higher comorbidity burdens. Compared with BMI levels between 22.5 and 24.9 kg m(-2), the adjusted relative hazards for 3-year mortality in subjects with HF-REF were: hazard ratios (HR)=1.31 (95% confidence interval=1.15-1.50) for BMI <22.5, 0.85 (0.76-0.96) for BMI 25.0-29.9, 0.64 (0.55-0.74) for BMI 30.0-34.9 and 0.95 (0.78-1.15) for BMI ≥35. Corresponding adjusted HRs for those with HF-PEF were: 1.12 (95% confidence interval=0.80-1.57) for BMI <22.5, 0.74 (0.56-0.97) for BMI 25.0-29.9, 0.64 (0.46-0.88) for BMI 30.0-34.9 and 0.71 (0.49-1.05) for BMI ≥35. CONCLUSIONS: In patients with chronic HF, the obesity paradox was present in both those with reduced and preserved ventricular systolic function. Mortality in both HF subtypes was U-shaped, with a nadir at 30.0-34.9 kg m(-2).

Vericiguat in heart failure: From scientific evidence to clinical practice.

Despite currently available treatments, risk of death and hospitalizations in patients with heart failure with reduced ejection fraction (HFrEF) remains high. The pathophysiology of HFrEF includes neurohormonal activation characterized by stimulation of deleterious pathways (i.e., sympathetic nervous and renin-angiotensin-aldosterone systems) and suppression of protective pathways such as nitric oxide-dependent pathways. Inhibition or stimulation of some, but not all, of these pathways is insufficient. In HFrEF, there is reduced nitric oxide, soluble guanylate cyclase, and cGMP activity, leading to deleterious effects in the myocardial, vascular, and renal systems. Vericiguat is able to stimulate the activity of this protective pathway. The VICTORIA study demonstrated that the addition of vericiguat to optimal medical treatment in patients with HFrEF and recent decompensation significantly reduced the incidence of the primary endpoint, a composite of cardiovascular death or HF hospitalization, with a number needed to treat of 24 patients and excellent tolerability.

Cardiomyogenic differentiation of human bone marrow mesenchymal cells: Role of cardiac extract from neonatal rat cardiomyocytes.

Bone marrow mesenchymal stromal cells (BM-MSCs) with regenerative potential have been identified in heart. Whether these cells become new cardiac lineage cells by phenomena of transdifferentiation or fusion is also being investigated. Although, these mechanisms give cardiomyocytes, it has to be considered that MSCs transplantation could carry out ossification and calcification processes. An alternative might be the use of myocytes; however, the problem is the arrythmia. For those reasons, is that we investigated how to obtain cardiomyocyte-like cells from human MSCs (hMSCs). The aim of the present work was to evaluate a nuclear reprogramming of the hMSCs by a neonatal rat cardiomyocytes extract (EX) using Streptolysin O (SLO) treatment. hMSCs treated with 57.5ng/ml SLO presented ball-like, stick-like and myotube-like morphology. In the absence of cardiomyogenic stimuli, hMSCs expressed markers of cardiac phenotype-like sarcomeric alpha-actinin, connexin-43 and GATA-4. However, when hMSCs were treated with SLO+EX or 10 microM of 5-azacytidine (5-AZA), the expression of these markers were significantly increased and furthermore, expressed SERCA-2, cardiac Troponin I, beta-MyHC, desmin, MLC-2a and MLC-2v thus showing the phenotype of mature cardiomyocytes. PCR analysis showed that cardiomyocyte-related genes, such as beta1-adrenergic receptor (beta1-AR), MLC-2a and cardiac Troponin T, were expressed after SLO+EX treatment like with 5-AZA. We concluded that the extract of neonatal rat cardiomyocytes could promote a nuclear modification of hMSCs to cardiomyogenic-like cells differentiation. Since the 5-AZA treatment appears to be genotoxic and taking into account the obtained results, the nuclear reprogramming by cell extract may be an approach leading to the identification of soluble factors that drives the reprogramming.

Particle size and cholesterol content of circulating HDL correlate with cardiovascular death in chronic heart failure.

Evidence regarding any association of HDL-particle (HDL-P) derangements and HDL-cholesterol content with cardiovascular (CV) death in chronic heart failure (HF) is lacking. To investigate the prognostic value of HDL-P size (HDL-Sz) and the number of cholesterol molecules per HDL-P for CV death in HF patients. Outpatient chronic HF patients were enrolled. Baseline HDL-P number, subfractions and HDL-Sz were measured using 1H-NMR spectroscopy. The HDL-C/P ratio was calculated as HDL-cholesterol over HDL-P. Endpoint was CV death, with non-CV death as the competing event. 422 patients were included and followed-up during a median of 4.1 (0-8) years. CV death occurred in 120 (30.5%) patients. Mean HDL-Sz was higher in CV dead as compared with survivors (8.39 nm vs. 8.31 nm, p < 0.001). This change in size was due to a reduction in the percentage of small HDL-P (54.6% vs. 60% for CV-death vs. alive; p < 0.001). HDL-C/P ratio was higher in the CV-death group (51.0 vs. 48.3, p < 0.001). HDL-Sz and HDL-C/P ratio were significantly associated with CV death after multivariable regression analysis (HR 1.22 [95% CI 1.01-1.47], p = 0.041 and HR 1.04 [95% CI 1.01-1.07], p = 0.008 respectively). HDL-Sz and HDL-C/P ratio are independent predictors of CV death in chronic HF patients.

Differences in the Interleukin-1ß/Soluble ST2 Interplay Between Acute and Chronic Heart Failure.

Recently, novel findings about the interleukin 1ß (IL-1 ß) axis in acute decompensated heart failure (ADHF) have been published. There is a positive correlation between IL-1 ß and interleukin-1 receptor like 1 (sST2) in ADHF patients. Is there also a correlation between the values of IL-1 ß and sST2 in chronic heart failure patients?

Growth differentiation factor-15 is a predictive biomarker in primary ventricular fibrillation: The RUTI-STEMI-PVF study.

BACKGROUND: Primary ventricular fibrillation is an ominous complication of ST-segment elevation myocardial infarction, and proper biomarkers for risk prediction are lacking. Growth differentiation factor-15 is a marker of inflammation, oxidative stress and hypoxia with well-established prognostic value in ST-segment elevation myocardial infarction patients. We explored the predictive value of growth differentiation factor-15 in a subgroup of ST-segment elevation myocardial infarction patients with primary ventricular fibrillation. METHODS: Prospective registry of ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention from February 2011-August 2015. Growth differentiation factor-15 concentrations were measured on admission. Logistic regression and Cox proportional regression analyses were used. RESULTS: A total of 1165 ST-segment elevation myocardial infarction patients treated with primary percutaneous coronary intervention (men 78.5%, age 62.3±13.1 years) and 72 patients with primary ventricular fibrillation (6.2%) were included. Compared to patients without primary ventricular fibrillation, median growth differentiation factor-15 concentration was two-fold higher in ST-segment elevation myocardial infarction patients with primary ventricular fibrillation (2655 vs 1367 pg/ml, p<0.001). At 30 days, mortality was 13.9% and 3.6% in patients with and without primary ventricular fibrillation, respectively (p<0.001), and median growth differentiation factor-15 concentration in patients with primary ventricular fibrillation was five-fold higher among those who died vs survivors (13,098 vs 2415 pg/ml, p<0.001). In a comprehensive multivariable analysis including age, sex, clinical variables, reperfusion time, left ventricular ejection fraction, N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T, growth differentiation factor-15 remained an independent predictor of 30-day mortality, with odds ratios of 3.92 (95% confidence interval 1.35-11.39) in patients with primary ventricular fibrillation (p=0.012) and 1.72 (95% confidence interval 1.23-2.40) in patients without primary ventricular fibrillation (p=0.001). CONCLUSIONS: Growth differentiation factor-15 is a robust independent predictor of 30-day mortality in ST-segment elevation myocardial infarction patients with primary ventricular fibrillation.

Hemosiderin deposits confounds tracking of iron-oxide-labeled stem cells: an experimental study.

BACKGROUND: The aim of the present research was to study the possible interference of hemosiderin deposits with the histological detection of dextran-coated, iron-labeled, mesenchymal stem cells after intracoronary administration in a porcine model of myocardial infarction. MATERIALS AND METHODS: A myocardial infarction was induced in six animals that received intracoronary iron-labeled autologous mesenchymal stem cells (group 1; n = 2) or placebo (group 2; n = 4). Six control animals without myocardial infarction underwent direct intramyocardial injections of iron-labeled autologous mesenchymal stem cells (group 3; n = 2) or placebo (group 4; n = 4). Histological sections from explanted hearts were stained with Prussian blue to identify dextran-coated, iron-labeled, mesenchymal stem cells. RESULTS: After Prussian blue staining, granular blue labeling in the tissue was observed in both groups of animals with infarcts. Similar granular blue labeling was detected in hearts from control animals without infarction that had received iron-labeled mesenchymal stem cells. However, hearts from control animals without infarction that received placebo did not have any granular blue labeling in the tissue. CONCLUSIONS: Hemosiderin from infarction hemorrhage interferes with detection of dextran-coated iron-labeled mesenchymal stem cells after intracoronary administration, suggesting that this marker is not useful to detect mesenchymal stem cells in a porcine model of myocardial infarction.

Umbilical cord blood-derived stem cells spontaneously express cardiomyogenic traits.

BACKGROUND: Umbilical cord blood (UCB) has been widely used for hematopoietic stem cell transplantation. The UCB-derived stem cells (UCBSCs) have been proposed as an alternative to bone marrow (BM)-derived mesenchymal stem cells (MSCs) for cardiac cell-based therapy. Herein we studied whether UCBSCs spontaneously exhibit cardiac-specific markers in vitro. METHODS: Human UCBSCs were isolated, expanded, and phenotyped by flow cytometry, quantitative RT-PCR, and immunofluorescence. Cell pluripotency and proliferation were also assessed by adipogenic and osteogenic media and in growth assays. RESULTS: Among 25 analyzed UCB, 16% of cases afforded primary culture satisfactory generation of UCBSCs. Duplication time (Td) of cultures was 2.16 +/- 0.06 days. The cells were strongly positive for CD105 (18.5 +/- 0.14), CD44 (27 +/- 2.8), CD166 (13 +/- 9), CD29 (59 +/- 9.4), CD90 (60 +/- 11) and consistently negative for CD117 (1.2 +/- 0.1), CD106 (1.1 +/- 0), CD34 (1.2 +/- 0.2), CD14 (1 +/- 0), and CD45 (1 +/- 0), consistent with a mesenchymal lineage. Adipogenesis and osteogenesis of cells resulted in low accumulation of intracellular lipid droplets and high deposition of calcium. The UCBSCs showed gene transcripts for alpha-actinin, connexin (Cx)-43, SERCA-2, and stromal cell-derived factor (SDF)-1alpha. At the protein level, the cells abundantly expressed alpha-actinin, Cx-43, SERCA-2 and SDF-1alpha. In contrast, these cells did not express the cardiac transcription factors GATA-4, Tbx5, and Nkx2.5, nor the sarcomeric proteins beta-myosin heavy chain (beta-MyHC) or cardiac troponin I (cTnI). CONCLUSIONS: Human UCBSCs may represent an alternative source of stem cells for myocardial-cell replacement. These cells can be highly expanded. They spontaneously express proteins of paramount importance for cardiovascular regeneration, such as Cx-43, SERCA-2, and SDF-1alpha.

Punto de corte óptimo del antígeno carbohidrato 125 para la identificación de pacientes con bajo riesgo tras un ingreso por insuficiencia cardiaca aguda / Optimal carbohydrate antigen 125 cutpoint for identifying low-risk patients after admission for acute heart failure

Introducción y objetivos: El antígeno carbohidrato 125 (CA125) se ha mostrado útil para la estratificación del riesgo de los pacientes ingresados por insuficiencia cardiaca aguda (ICA). Se intenta determinar un punto de corte para identificar a los pacientes con bajo riesgo de muerte y muerte/reingreso por insuficiencia cardiaca 1 mes tras el ingreso por ICA. Métodos: La cohorte de derivación incluyó a 3.231 pacientes con ICA consecutivos. Se identificaron valores de corte de CA125 con un valor predictivo negativo (VPN) del 90% y una sensibilidad de hasta el 85%. La idoneidad de estos puntos de corte y el riesgo de muerte/reingreso al mes se evaluaron mediante el método de Royston-Parmar. Se seleccionó el mejor punto de corte y se validó en una cohorte del BIOSTAT-CHF (n=1.583). Resultados: En la cohorte de derivación, la mediana [intervalo intercuartílico] de CA125 fue 57 [25,3-157] U/ml. El punto de corte óptimo fue <23 U/ml (el 21,5% de los pacientes), con VPN de muerte y del objetivo compuesto del 99,3 y el 94,1% respectivamente. En los análisis multivariables, el CA125 <23 U/ml se asoció con un menores riesgos de muerte (HR=0,20; IC95%, 0,08-0,50; p <0,001) y del objetivo combinado (HR=0,63; IC95%, 950,45-0,90; p=0,009). Su capacidad para discriminar a los pacientes con riesgo bajo a 1 mes se confirmó en la cohorte de validación (VPN de muerte y del objetivo compuesto, el 98,6 y el 96,6%). La capacidad predictiva seguía siendo significativa a los 6 meses de seguimiento. Conclusiones: En pacientes ingresados por ICA, el CA125 <23 U/ml identificó un subgrupo de pacientes con bajo riesgo de eventos clínicos adversos a corto plazo que pueden no requerir un seguimiento estrecho (AU)

Introduction and objectives: Carbohydrate antigen 125 (CA125) has been shown to be useful for risk stratification in patients admitted with acute heart failure (AHF). We sought to determine a CA125 cutpoint for identifying patients at low risk of 1-month death or the composite of death/HF readmission following admission for AHF. Methods: The derivation cohort included 3231 consecutive patients with AHF. CA125 cutoff values with 90% negative predictive value (NPV) and sensitivity up to 85% were identified. The adequacy of these cutpoints and the risk of 1-month death/HF readmission was then tested using the Royston-Parmar method. The best cutpoint was selected and externally validated in a cohort of patients hospitalized from BIOSTAT-CHF (n=1583). Results: In the derivation cohort, the median [IQR] CA125 was 57 [25.3-157] U/mL. The optimal cutoff value was <23 U/mL (21.5% of patients), with NPVs of 99.3% and 94.1% for death and the composite endpoint, respectively. On multivariate survival analyses, CA125 <23 U/mL was independently associated with a lower risk of death (HR, 0.20; 95%CI, 0.08-0.50; P <.001), and the combined endpoint (HR, 0.63; 95%CI, 950.45-0.90; P=.009). The ability of this cutpoint to discriminate patients at a low 1-month risk was confirmed in the validation cohort (NPVs of 98.6% and 96.6% for death and the composite endpoint). The predicted ability of this cutoff remained significant at 6 months of follow-up. Conclusions: In patients admitted with AHF, CA125 <23 U/mL identified a subgroup at low risk of short-term adverse events, a population that may not require intense postdischarge monitoring (AU)

Vericiguat en insuficiencia cardíaca: de la evidencia científica a la práctica clínica / Vericiguat in heart failure: from scientific evidence to clinical practice

A pesar de los tratamientos actuales, el riesgo de muerte y hospitalizaciones en pacientes con insuficiencia cardíaca con fracción de eyección reducida (IC-FEr) sigue siendo elevado. La fisiopatología de la IC-FEr incluye activación neurohormonal caracterizada por la estimulación de las vías deletéreas (sistemas simpático y renina-angiotensina-aldosterona) y la supresión de las vías protectoras como las dependientes del óxido nítrico. La inhibición o estimulación de algunas de estas vías, pero no de todas, es insuficiente. En la IC-FEr existe una menor actividad de óxido nítrico, guanilato ciclasa soluble y GMPc que provoca efectos deletéreos a nivel miocárdico, vascular y renal. Vericiguat estimula la actividad de esta vía protectora. El estudio VICTORIA demostró, en pacientes con IC-FEr y descompensación reciente, que la adición de vericiguat al tratamiento médico óptimo reducía de forma significativa la incidencia del objetivo primario compuesto de muerte cardiovascular u hospitalización por IC, con un número de 24 pacientes que es necesario tratar, y una excelente tolerabilidad (AU)

Despite currently available treatments, risk of death and hospitalizations in patients with heart failure with reduced ejection fraction (HFrEF) remains high. The pathophysiology of HFrEF includes neurohormonal activation characterized by stimulation of deleterious pathways (i.e., sympathetic nervous and renin-angiotensin-aldosterone systems) and suppression of protective pathways such as nitric oxide-dependent pathways. Inhibition or stimulation of some, but not all, of these pathways is insufficient. In HFrEF, there is reduced nitric oxide, soluble guanylate cyclase, and cGMP activity, leading to deleterious effects in the myocardial, vascular, and renal systems. Vericiguat is able to stimulate the activity of this protective pathway. The VICTORIA study demonstrated that the addition of vericiguat to optimal medical treatment in patients with HFrEF and recent decompensation significantly reduced the incidence of the primary endpoint, a composite of cardiovascular death or HF hospitalization, with a number needed to treat of 24 patients and excellent tolerability (AU)

The insulin-like growth factor axis: A review of atherosclerosis and restenosis.

Insulin-like growth factors I and II (IGF-I and -II) and their regulatory proteins are secreted by cells of the cardiovascular system. They are growth promoters for arterial cells and mediators of cardiovascular disease. IGFs are bound to IGF binding proteins (IGFBPs), which modulate IGF ligand-receptor interaction and consequently to IGF action. IGFBPs are in turn posttranslationally modulated by specific proteases. This dynamic balance (IGFs, IGFBPs, and IGFBP proteases) constitutes the IGF axis and ultimately determines the extent of IGF-dependent cellular effects. Dysregulated actions of this axis influence coronary atherosclerosis through effects on vascular smooth muscle cell growth, migration, and extracellular matrix synthesis in the atherosclerotic plaque. IGF-I promotes macrophage chemotaxis, excess LDL cholesterol uptake, and release of proinflammatory cytokines. Endothelial cells also receive the effects of IGFs stimulating their migration and organization forming capillary networks. Neointimal hyperplasia of restenosis after coronary artery injury is also modulated by the IGF axis. IGFs stimulate vascular smooth muscle cell proliferation and migration to form the neointima and upregulate tropoelastin synthesis after disruption of the elastic layer. Understanding IGF axis regulation establishes a scientific basis for strategies directed to limit or reverse plaque growth and vulnerability in atherosclerosis and in the neointimal hyperplasia of restenosis.

Consensus document and recommendations on the use of natriuretic peptides in clinical practice. / Documento de consenso y recomendaciones sobre el uso de los péptidos natriuréticos en la práctica clínica.

Natriuretic peptides are a useful laboratory tool for the diagnosis, prognosis and treatment of patients with heart failure. Natriuretic peptides are used in various healthcare settings (consultations, emergency department, hospitalization, laboratory) and by various primary care and specialised professionals. However, their use in clinical practice is still scare and uneven. Properly using and interpreting natriuretic peptides in clinical practice requires a minimum of prelaboratory (pathophysiology), laboratory (methods) and postlaboratory (interpretation and integration of clinical data) expertise. The objective of this consensus document, developed by several scientific societies, is to update the necessary concepts and expertise on natriuretic peptides that enable its application in the diagnosis, prognosis and treatment of heart failure, in various healthcare environments.

Pressure rinsing of coronary stents immediately before implantation reduces inflammation and neointimal hyperplasia.

OBJECTIVES: This study evaluates whether rinsing stents with high pressure immediately before implantation minimizes stent-induced inflammation and neointimal formation. BACKGROUND: Several reports indicate that manual stent manipulation before implantation results in foreign body contamination and increased neointimal hyperplasia. METHODS: A stent-cleaning chamber was developed to rinse stents at a sustained hydrodynamic pressure of 4 atm for 10 s. Commercial pre-mounted stents were examined with different levels of manipulation: 1) untouched stents: no stent manipulation before implantation; 2) handled stents: manual stent re-crimping on the balloon; 3) rinsed stents: pressure-rinsed with the stent-cleaning chamber. In vitro surface analysis was evaluated by scanning electron microscopy. Neointimal hyperplasia and inflammation around stent struts were also assessed in the pig in-stent restenosis model. RESULTS: In vitro analysis revealed fewer contaminants on rinsed stents compared with untouched (p = 0.01) and handled stents (p < 0.001). In vivo, neointimal thickness, neointimal area and vessel percent stenosis were significantly reduced in rinsed, compared with not-rinsed, stents (p = 0.002, p = 0.007, p = 0.008 respectively). In addition, a significant reduction in the inflammatory infiltrate around struts was observed in untouched, compared with handled, stents (p = 0.04) and in rinsed, compared with not-rinsed, stents (p < 0.001). Regression analysis accounting for injury and neointimal thickness showed significant differences in slopes between "handled + not-rinsed" and "handled + rinsed" stents (p = 0.004), and between "untouched + not-rinsed" and "untouched + rinsed stents" (p = 0.037). CONCLUSIONS: Rinsing stents under high pressure immediately before coronary implantation results in less inflammation around struts and thinner neointima at 28 days in this pig model.

Insulin-like growth factor binding protein-4 protease produced by smooth muscle cells increases in the coronary artery after angioplasty.

Insulin-like growth factor (IGF)-I stimulates vascular smooth muscle cell (VSMC) migration and proliferation, which are fundamental to neointimal hyperplasia in postangioplasty restenosis. IGF-I action is modulated by several high-affinity IGF binding proteins (IGFBPs). IGFBP-4 is the predominant IGFBP produced by VSMCs and is a potent inhibitor of IGF-I action. However, specific IGFBP-4 proteases can cleave IGFBP-4 and liberate active IGF-I. In this study, we document IGFBP-4 protease produced by human and porcine coronary artery VSMCs in culture as pregnancy-associated plasma protein-A (PAPP-A). This was shown by a distinctive IGFBP-4 cleavage pattern, specific inhibition of IGFBP-4 protease activity with PAPP-A polyclonal antibodies, and immunorecognition of PAPP-A by monoclonal antibodies. Furthermore, we found a 2-fold increase in IGFBP-4 protease activity in injured porcine VSMC cultures in vitro (P<0.05). We also evaluated IGFBP-4 protease/PAPP-A expression in vivo after coronary artery balloon injury. Twenty-five immature female pigs underwent coronary overstretch balloon injury, and vessels were examined at defined time points after the procedure. Abundant PAPP-A expression was observed in the cytoplasm of medial and neointimal cells 7, 14, and 28 days after angioplasty (P<0.01 vs control). The highest PAPP-A labeling indices were located in the neointima (36.1+/-2.1%) and the media (31.7+/-1.2%) 28 days after injury. Western blot analysis confirmed increased PAPP-A in injured vessels. PAPP-A, a regulator of IGF-I bioavailability through proteolysis of IGFBP-4, is thus expressed by VSMCs in vitro and in restenotic lesions in vivo. These results suggest a possible role for PAPP-A in neointimal hyperplasia.

New approaches to the pharmacological treatment of angina.

The treatment of angina is changing, with many new agents being added to those existing agents that have been used for many years. New data regarding the use of glycoprotein IIb/IIIa inhibitors now exist and low molecular weight heparins are used more frequently with greater efficacy than unfractionated heparin. New thrombin inhibitors are also receiving a fresh look. An expert panel has recently published guidelines for the treatment of unstable angina.

Identification of cardiomyogenic lineage markers in untreated human bone marrow-derived mesenchymal stem cells.

BACKGROUND: Recent reports refute the classic paradigm by which human heart is unable to repair itself following disease or injury. Cardiac and noncardiac stem cells with cardiac regeneration potential have been documented. We studied whether untreated mesenchymal stem cells express markers of cardiomyogenic lineage in vitro. METHODS: Mesenchymal stem cells were obtained from human iliac crest marrow aspirates. Cells were isolated and characterized using flow cytometry by surface expression of CD105, CD166, CD29, CD44, CD14, and CD34. To evaluate their cardiomyogenic potential, presence of cardiac proteins (cardiac troponin I, sarcomeric alpha-actinin, beta myosin heavy chain (beta-MyHC), connexin-43, and SERCA-2), and transcription factors (GATA-4) were assessed. RESULTS: Mesenchymal stem cells expressed CD105 (4.25 +/- 0.35), CD166 (27.83 +/- 1.89), and CD29 (9.4 +/- 0.57) and were negative for CD34, CD14, and CD45. In absence of additional stimuli in the culture media, these cells expressed connexin-43, alpha-actinin, and GATA-4, and were negative for SERCA-2, cardiac troponin I, and beta-MyHC. CONCLUSIONS: Human adult mesenchymal stem cells spontaneously exhibit markers of cardiac phenotype in vitro. In the appropiate myocardial environment, these cells may transdifferentiate into mature cardiomyocytes.

Circulating soluble low-density lipoprotein receptor-related protein 1 (sLRP1) concentration is associated with hypercholesterolemia: A new potential biomarker for atherosclerosis.

BACKGROUND: There is clinical interest in identifying novel lipid biomarkers for evaluating cardiovascular risk and targeting lipid-lowering treatment. Low-density lipoprotein receptor-related protein 1 (LRP1) plays a crucial role in the dysregulated cholesterol transfer from modified lipoproteins to human coronary vascular smooth muscle cells (hVSMCs), promoting hVSMC-derived foam cell formation. LRP1 has a soluble and circulating form (sLRP1) generated from LRP1. Cholesterol modulates the release of the soluble form of LRP1. Using in vitro, ex vivo and patient-based approaches, we tested the association between circulating sLRP1 concentrations and hypercholesterolemia and the potential of sLRP1 as a biomarker of atherosclerosis. METHODS AND RESULTS: Circulating sLRP1 concentrations were higher in severe hypercholesterolemia compared to moderate hypercholesterolemia or normocholesterolemia (Study 1). Circulating sLRP1 was significantly associated with established pro-atherogenic lipid parameters in two different hypercholesterolemic populations (Studies 2 and 3). sLRP1 concentrations decreased after statin treatment and increased after statin withdrawal (Study 3). In vitro experiments showed that native LDL, aggregated LDL and VLDL+IDL lipoproteins induced the release of sLRP1 from hVSMC. sLRP1 levels were increased in the conditioned medium of coronary atherosclerotic plaque areas extracted from patients compared to non-atherosclerotic areas of the same coronary artery and patient. Circulating sLRP1 concentrations were independently associated with the occurrence of carotid atherosclerosis in a hypercholesterolemic population (Study 2). The later association was higher than that observed for other classical or novel lipid parameters. CONCLUSIONS: Circulating sLRP1 is a new lipid-related parameter potentially useful as a biomarker for atherosclerosis.