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Publicaciones científicas más recientes (desde 2010)

Autores: Moreno, MU; Gavira, Juan José; et al.
ISSN 0025-7125  Vol. 101  Nº 1  2017  págs. 43-52
The chronic hemodynamic load imposed by hypertension on the left ventricle leads to lesions in the myocardium that result in structural remodeling, which provides support for alterations in cardiac function, perfusion, and electrical activity that adversely influence the clinical evolution of hypertensive heart disease. Management must include detecting, reducing, and reversing left ventricular hypertrophy, as well as the detection and repair of microscopic lesions responsible for myocardial remodeling. Reducing the burden associated with hypertensive heart disease can be targeted using personalized treatment. The noninvasive, biomarker-mediated identification of subsets of patients with hypertensive heart disease is essential to provide personalized treatment.
Autores: Ravassa, S; López, B; Querejeta, R.; et al.
ISSN 1473-5598  Vol. 35  Nº 4  2017  págs. 853 - 861
OBJECTIVE: Myocardial fibrosis is associated with alterations in the cross-linking and deposition of collagen type I (CCL and CD, respectively). We aimed to evaluate whether the combination of circulating biomarkers of CCL [the carboxy-terminal telopeptide of collagen type I to matrix metalloproteinase-1 ratio (CITP¿:¿MMP-1)] and CD [the carboxy-terminal propeptide of procollagen type I (PICP)] identifies myocardial fibrosis phenotypes with distinct clinical outcome in hypertensive patients with heart failure. METHODS: Endomyocardial biopsies and blood samples from 38 patients (small cohort), and blood samples from 203 patients (large cohort) were analyzed. Myocardial CCL and CD were assessed by histological methods. Serum PICP, CITP, and MMP-1 were determined by ELISA. RESULTS: Small cohort: CITP¿:¿MMP-1 cutoff 1.968 or less and PICP cutoff at least 110.8¿ng/ml were used for predicting high CCL and severe CD, respectively. Large cohort: as defined by the above thresholds, patients were categorized into four subgroups based on the presence (+) or absence (-) of high CCL and severe CD. Compared with CCL-CD-, the adjusted hazard ratios for a composite end point of heart failure hospitalization or cardiovascular death over 5 years in CCL-CD+, CCL+CD-, and CCL+CD+ were 1.11 (P¿=¿0.79), 1.99 (P¿=¿0.07), and 2.18 (P¿=¿0.04), respectively (P for trend¿=¿0.005). In addition, the categorization based on CCL and CD yielded integrated discrimination (P¿=¿0.03) and net reclassification..
Autores: Beloqui, Óscar; Moreno, MU; San José, Gorka; et al.
ISSN 1071-5762  Vol. 51  Nº 4  2017  págs. 389 - 396
Vascular calcification is a common feature in atherosclerosis and associates with cardiovascular events. Oxidative stress may be involved in the pathogenesis of vascular calcification. Previous studies have shown that the phagocytic NADPH oxidase is associated with atherosclerosis. The objective of the present study was to investigate the association between phagocytic NADPH oxidase-mediated superoxide production and coronary artery calcium (CAC). NADPH oxidase-mediated superoxide production was determined by chemiluminescence and CAC by computed tomography in 159 asymptomatic men free of overt clinical atherosclerosis. Multivariate linear regression analyses were used to assess the relationship between CAC and NADPH oxidase-mediated superoxide production. Compared with individuals in the lowest score of CAC (= 0 Agatston units), those in the upper score (> 400 Agatston units) showed higher superoxide production (p < 0.05). In correlation analysis, superoxide production positively (p < 0.01) correlated with CAC, which in multivariate analysis remained significant after adjusting for age, HDL-cholesterol, triglycerides, body mass index, smoking, arterial hypertension and diabetes mellitus. In conclusion, in a population of men without clinically overt atherosclerotic disease, increased NADPH oxidase-mediated superoxide production associated with enhanced CAC. Albeit descriptive, these findings suggest a potential involvement of phagocytic NADPH oxidase-mediated oxidative stress in CAC.
Autores: Beaumont Javier; San José, Gorka; Moreno, MU; et al.
ISSN 2045-2322  Vol. 7  2017  págs. 41865
Excessive myocardial collagen deposition and cross-linking (CCL), a process regulated by lysyl oxidase (LOX), determines left ventricular (LV) stiffness and dysfunction. The angiotensin II antagonist losartan, metabolized to the EXP3179 and EXP3174 metabolites, reduces myocardial fibrosis and LV stiffness in hypertensive patients. Our aim was to investigate the differential influence of losartan metabolites on myocardial LOX and CCL in an experimental model of hypertension with myocardial fibrosis, and whether EXP3179 and EXP3174 modify LOX expression and activity in fibroblasts. In rats treated with NG-nitro-L-arginine methyl ester (L-NAME), administration of EXP3179 fully prevented LOX, CCL and connective tissue growth factor (CTGF) increase, as well as fibrosis, without normalization of blood pressure (BP). In contrast, administration of EXP3174 normalized BP and attenuated fibrosis but did not modify LOX, CCL and CTGF. In TGF-beta(1)-stimulated fibroblasts, EXP3179 inhibited CTGF and LOX expression and activity with lower IC50 values than EXP3174. Our results indicate that, despite a lower antihypertensive effect, EXP3179 shows higher anti-fibrotic efficacy than EXP3174, likely through its ability to prevent the excess of LOX and CCL. It is suggested that the anti-fibrotic effect of EXP3179 may be partially mediated by the blockade of CTGF-induced LOX in fibroblasts.
Autores: Beaumont Javier; López, B; Ravassa, S; et al.
ISSN 2045-2322  Vol. 7  2017  págs. 40696
This study analyzed the potential associations of 7 myocardial fibrosis-related microRNAs with the quality of the collagen network (e.g., the degree of collagen fibril cross-linking or CCL) and the enzyme lysyl oxidase (LOX) responsible for CCL in 28 patients with severe aortic stenosis (AS) of whom 46% had a diagnosis of chronic heart failure (HF). MicroRNA expression was analyzed in myocardial and blood samples. From the studied microRNAs only miR-19b presented a direct correlation (p < 0.05) between serum and myocardium. Compared to controls both myocardial and serum miR-19b were reduced (p < 0.01) in AS patients. In addition, miR-19b was reduced in the myocardium (p < 0.01) and serum (p < 0.05) of patients with HF compared to patients without HF. Myocardial and serum miR-19b were inversely correlated (p < 0.05) with LOX, CCL and LV stiffness in AS patients. In in vitro studies miR-19b inhibition increased (p < 0.05) connective tissue growth factor protein and LOX protein expression in human fibroblasts. In conclusion, decreased miR-19b may be involved in myocardial LOX up-regulation and excessive CCL, and consequently increased LV stiffness in AS patients, namely in those with HF. Serum miR-19b can be a biomarker of these alterations of the myocardial collagen network in AS patients, particularly in patients with HF.
Autores: González, A; López, B; et al.
ISSN 1388-9842  Vol. 19  Nº Supl. 1  2017  págs. 9 - 10
Autores: Huerta, Ana; López, B; Ravassa, S; et al.
ISSN 0263-6352  Vol. 34  Nº 1  2016  págs. 130 - 138
OBJECTIVES: Cystatin C has been shown to be associated with heart failure with preserved ejection fraction (HFPEF). In addition, myocardial fibrosis has been involved in diastolic dysfunction in HFPEF. Therefore, we hypothesized that increased cystatin C levels may be associated with altered collagen metabolism, contributing to diastolic dysfunction in patients with HFPEF. METHODS: One hundred and forty-one elderly hypertensive patients with HFPEF were included. Cardiac morphology and function was assessed by echocardiography. Circulating levels of cystatin C, biomarkers of collagen type I synthesis (carboxy-terminal propeptide of procollagen type I) and degradation [matrix metalloproteinase-1 (MMP-1) and its inhibitor TIMP-1] and osteopontin were analyzed by ELISA. Twenty elderly sex-matched patients with no identifiable cardiac disease were used as controls. In-vitro studies were performed in human cardiac fibroblasts. RESULTS: Compared with controls, cystatin C was increased (P¿<¿0.001) in patients with HFPEF, even in those with a normal estimated glomerular filtration rate (eGFR; P¿<¿0.05). Cystatin C was directly correlated with the estimated pulmonary capillary wedge pressure (P¿<¿0.01), TIMP-1 and osteopontin (P¿<¿0.001) and inversely correlated with MMP-1:TIMP-1 (P¿<¿0.01), but not with carboxy-terminal propeptide of procollagen type I or MMP-1 in all patients with HFPEF. These associations were independent of eGFR. In vitro, osteopontin (P¿<¿0.01) and TIMP-1 (P¿<¿0.0
Autores: López, B; Ravassa, S; González, A; et al.
ISSN 0735-1097  Vol. 67  Nº 3  2016  págs. 251 - 260
BACKGROUND: Excessive myocardial collagen cross-linking (CCL) determines myocardial collagen's resistance to degradation by matrix metalloproteinase (MMP)-1 and interstitial accumulation of collagen fibers with impairment of cardiac function. OBJECTIVES: This study sought to investigate whether CCL and a newly identified biomarker of this alteration are associated with hospitalization for heart failure (HHF) or cardiovascular death in patients with HF and arterial hypertension in whom other comorbidities were excluded. METHODS: Endomyocardial biopsies and blood samples from 38 patients (invasive study), and blood samples from 203 patients (noninvasive study) were analyzed. Mean follow-ups were 7.74 ± 0.58 years and 4.72 ± 0.11 years, respectively. Myocardial CCL was calculated as the ratio between insoluble and soluble collagen. The ratio between the C-terminal telopeptide of collagen type I (CITP) and matrix metalloproteinase-1 (CITP:MMP-1) was determined in blood samples. RESULTS: Invasive study: CCL was increased (p < 0.001) in patients compared with controls. Patients were categorized according to normal or high CCL values. Patients with high CCL exhibited higher risk for subsequent HHF (log-rank test p = 0.022), but not for cardiovascular death. CITP:MMP-1 was inversely associated with CCL (r = -0.460; p = 0.005) in all patients. Receiver operating characteristic curves rendered a CITP:MMP-1 cutoff ¿1.968 (80% sensitivity and 76% specificity) for predicting high CCL. Noninvasive study: Patients were categorized according to CITP:MMP-1 ratio values as normal ratio (>1.968) or low ratio (¿1.968). Patients with a low ratio exhibited higher risk for HHF (log-rank test p = 0.014), which remained significant after adjustment for relevant covariables (adjusted hazard ratio: 2.22; 95% CI: 1.37 to 3.59, p = 0.001). In addition, CITP:MMP-1-based categorization yielded significant integrated discrimination and net reclassification improvements (p = 0.003 and p = 0.009, respectively) for HHF over relevant risk factors. CITP:MMP-1 was not associated with the risk of cardiovascular death. CONCLUSIONS: Excessive myocardial CCL is associated with HHF in hypertensive patients with HF. In this population, the serum CITP:MMP-1 ratio identifies patients with increased CCL and high risk of HHF.
Autores: López, B; González, A; Ravassa, S; et al.
ISSN 0735-1097  Vol. 65  Nº 22  2015  págs. 2449 - 2456
Myocardial fibrosis impairs cardiac function, in addition to facilitating arrhythmias and ischemia, and thus influences the evolution and outcome of cardiac diseases. Its assessment is therefore clinically relevant. Although tissue biopsy is the gold standard for the diagnosis of myocardial fibrosis, a number of circulating biomarkers have been proposed for the noninvasive assessment of this lesion. A review of the published clinical data available on these biomarkers shows that most of them lack proof that they actually reflect the myocardial accumulation of fibrous tissue. In this "call to action" article, we propose that this absence of proof may lead to misinterpretations when considering the incremental value provided by the biomarkers with respect to traditional diagnostic tools in the clinical handling of patients. We thus argue that strategies are needed to more strictly validate whether a given circulating biomarker actually reflects histologically proven myocardial fibrosis before it is applied clinically.
Autores: Moreno, MU; San José, Gorka; Pejenaute, Á.; et al.
ISSN 0194-911X  Vol. 63  Nº 3  2014  págs. 468 - 474
Left ventricular hypertrophy (LVH) is an independent marker of mortality in hypertension. Although the mechanisms contributing to LVH are complex, inflammation and oxidative stress may favor its development. We analyzed the association of the phagocytic NADPH oxidase-mediated superoxide anion release and LVH in patients with essential hypertension and the role of cardiotrophin-1 (CT-1) and interleukin-6 (IL-6), cytokines implicated in cardiac growth. Blood pressure, echocardiography data, and serum CT-1 and IL-6 levels were obtained in 140 subjects: 18 normotensives without LVH, 42 hypertensives without LVH, and 80 hypertensives with LVH. The NADPH oxidase-dependent superoxide production was assessed by chemiluminescence in peripheral blood mononuclear cells. Peripheral blood mononuclear cells were stimulated with CT-1 in vitro. Superoxide anion production by peripheral blood mononuclear cells associated with LVH and correlated with the left ventricular mass index. Serum CT-1 and IL-6 levels, which associated with the left ventricular mass index, correlated with superoxide production. Serum CT-1 and IL-6 levels were correlated. CT-1 stimulated NADPH oxidase superoxide production in peripheral blood mononuclear cells, which resulted in an increased release of IL-6. Our results show that superoxide anion production by the phagocytic NADPH oxidase associates with hypertensive heart disease, being significantly enhanced in hypertensive patients with LVH. This may be attributable to the activation of the NADPH oxidase by CT-1 and the subsequent release of IL-6. The phagocytic NADPH oxidase may be a therapeutic target in hypertensive heart disease.
Autores: Beaumont Javier; López, B; et al.
ISSN 0143-5221  Vol. 126  Nº 7  2014  págs. 497 - 506
miRNAs (microRNAs) have been shown to play a role in myocardial fibrosis. The present study was designed to analyse whether alterations in miRNA expression contribute to the progression of myocardial fibrosis in AS (aortic valve stenosis) patients through up-regulation of the pro-fibrotic factor TGF-ß1 (transforming growth factor-ß type 1). Endomyocardial biopsies were obtained from 28 patients with severe AS, and from the necropsies of 10 control subjects. AS patients presented increased myocardial CVF (collagen volume fraction) and TGF-ß1 compared with the controls, these parameters being correlated in all patients. Patients were divided into two groups by cluster analysis according to their CVF: SF (severe fibrosis; CVF >15%; n=15) and non-SF (CVF ¿15%; n=13). TGF-ß1 was increased in patients with SF compared with those with non-SF. To analyse the involvement of miRNAs in SF, the miRNA expression profile of 10 patients (four with non-SF and six with SF) was analysed showing that 99 miRNAs were down-regulated and 19 up-regulated in the SF patients compared with the non-SF patients. Those miRNAs potentially targeting TGF-ß1 were validated by real-time RT (reverse transcription)-PCR in the whole test population, corroborating that miR-122 and miR-18b were down-regulated in patients with SF compared with those with non-SF and the control subjects. Additionally, miR-122 was inversely correlated with the CVF, TGF-ß1 and the TGF-ß1-regulated PCPE-1 (procollagen C-terminal proteinase enhancer-1) in all patients. Experiments in human fibroblasts demonstrated that miR-122 targets and inhibits TGF-ß1. In conclusion, for the first time we show that myocardial down-regulation of miR-122 might be involved in myocardial fibrosis in AS patients, probably through TGF-ß1 up-regulation.
Autores: San José, Gorka; Moreno, MU; et al.
ISSN 1523-0864  Vol. 19  Nº 14  2013  págs. 1607 - 1618
Aims: The NADPH oxidases constitute a major source of superoxide anion (·O2¿) in hypertension. Several studies suggest an important role of NADPH oxidases in different effects mediated by transforming growth factor-ß1 (TGF-ß1). We investigated whether a chronic treatment with P144, a peptide synthesized from type III TGF-ß1 receptor, inhibited NADPH oxidases in the renal cortex of spontaneously hypertensive rats (SHR). Results: Here, we show that chronic administration of P144 significantly reduced the NADPH oxidase expression and activity as well as the oxidative stress observed in control vehicle-treated SHR (V-SHR). In addition, P144 was also able to reduce the significant increase in the renal fibrosis and in mRNA expression of different components of collagen metabolism, as well as in the levels of connective tissue growth factor observed in V-SHR. Finally, TGF-ß1-stimulated NRK52E exhibited a significant increase in NADPH oxidase expression and activity as well as a TGF-ß1-dependent intracellular pathway that were inhibited in the presence of P144. Innovation: Our experimental evidence suggests that reversing oxidative stress may be therapeutically useful in preventing fibrosis-associated renal damage. We show here that (i) the TGF-ß1-NADPH oxidases axis is crucial in the development of fibrosis in an experimental hypertensive renal disease animal model, and (ii) the use of P144 reverses TGF-ß1-dependent NADPH oxidase activity; thus, P144 may be considered a novel therapeutic tool in kidney disease associated with hypertension. Conclusion: We demonstrate that P144 inhibits NADPH oxidases and prevents oxidative stress in kidneys from hypertensive rats. Our data also suggest that these effects are associated with the renal antifibrotic effect of P144.
Autores: Moreno, MU; Gallego, Idoia; López, B; et al.
ISSN 0143-5221  Vol. 125  Nº 6  2013  págs. 291 - 300
The NADPH oxidases are a key family of ROS (reactive oxygen species)-producing enzymes which may differentially contribute to cardiac pathophysiology. Animal studies show uncertain results regarding the regulation of cardiac Nox4 by pressure overload and no data are available on human myocardial Nox4. In the present study, we evaluated Nox4 expression and its relationship with myocardial remodelling and LV (left ventricular) function in patients with severe AS (aortic valve stenosis). Endomyocardial biopsies from 34 patients with AS were obtained during aortic valve replacement surgery. LV morphology and function were assessed by echocardiography. Myocardial samples from subjects deceased of non-CVDs (cardiovascular diseases) were analysed as controls. Nox4 localization was evaluated by immunohistochemistry and quantified by Western blot. Myocardial capillary density, fibrosis and cardiomyocyte dimensions and apoptosis were assessed histologically to evaluate myocardial remodelling. Nox4 was present in samples from all subjects and expressed in cardiomyocytes, VSMCs (vascular smooth muscle cells), endothelium and fibroblasts. Nox4 levels were reduced 5-fold in AS patients compared with controls (P<0.01). Nox4 levels directly correlated with cardiomyocyte cross-sectional area (r=0.299, P<0.05) and diameter (r=0.406, P<0.05) and capillary density (r=0.389, P<0.05), and inversely with cardiomyocyte apoptosis (r=-0.316, P<0.05) in AS patients. In addition, Nox4 levels correlated with echocardiographic parameters (LV ejection fraction: r=0.353, P<0.05; midwall fractional shortening: r=0.355, P<0.05; deceleration time: r=-0.345, P<0.05) in AS patients. Nox4 is expressed in human myocardium and reduced in AS patients. The observed associations of Nox4 with cardiomyocyte parameters and capillary density in AS patients suggest a potential role of Nox4 deficiency in the myocardial remodelling present in the human pressure-overloaded heart.
Autores: Anilkumar, N. ; San José, Gorka; Sawyer, I. ; et al.
ISSN 1079-5642  Vol. 33  Nº 4  2013  págs. e104 - e112
OBJECTIVE: Reactive oxygen species-generating nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase proteins (Noxs) are involved in cell differentiation, migration, and apoptosis. Nox4 is unique among Noxs in being constitutively active, and its subcellular localization may therefore be particularly important. In this study, we identified and characterized a novel nuclear-localized 28-kDa splice variant of Nox4 in vascular cells. APPROACH AND RESULTS:Nox4 immunoreactivity was noted in the nucleus and nucleolus of vascular smooth muscle cells and multiple other cell types by confocal microscopy. Cell fractionation, sequence analyses, and siRNA studies indicated that the nuclear-localized Nox4 is a 28-kDa splice variant, Nox4D, which lacks putative transmembrane domains. Nox4D overexpression resulted in significant NADPH-dependent reactive oxygen species production as detected by several different methods and caused increased phosphorylation of extracellular-signal-regulated kinase1/2 and the nuclear transcription factor Elk-1. Overexpression of Nox4D could also induce DNA damage as assessed by ¿-H2AX phosphorylation. These effects were inhibited by a single amino acid substitution in the Nox4D NADPH-binding region. CONCLUSIONS:Nox4D is a nuclear-localized and functionally active splice variant of Nox4 that may have important pathophysiologic effects through modulation of nuclear signaling and DNA damage.
Autores: Moreno, MU; San José, Gorka; Fortuño, Ana; et al.
ISSN 1945-0494  Vol. 3  2011  págs. 1467 - 1474
Oxidative stress is implicated in diabetes. The NADPH oxidases are the main source of superoxide in phagocytic and vascular cells, and p22phox is a key subunit. Genetic variants of CYBA, the human p22phox gene, associate with cardiovascular disease. We investigated the association of the A640G polymorphism with diabetes and its impact on phagocytic NADPH oxidase-dependent superoxide production and subclinical atherosclerosis. We studied 1212 subjects in which clinical parameters including carotid intima-media thickness (cIMT) were assessed. The A640G polymorphism was genotyped by TaqMan probes. In 496 subjects, the NADPH oxidase-dependent superoxide production in peripheral blood mononuclear cells was assessed by chemiluminescence. The GG genotype prevalence was significantly higher in type 2 diabetic patients than in non-diabetic subjects. Peripheral blood mononuclear cells from diabetic GG patients presented higher NADPH oxidase-dependent superoxide production than those of diabetic AA/AG patients. Within the diabetic group, GG patients presented higher cIMT levels than AA/AG patients. The A640G CYBA polymorphism may be a marker of oxidative stress risk and may be indicative of subclinical atherosclerosis in type 2 diabetes.
Autores: San José, Gorka; Rodríguez, C.; et al.
ISSN 0008-6363  Vol. 92  Nº 2  2011  págs. 247 - 255
Aims Cardiotrophin-1 (CT-1) is a cytokine of the interleukin-6 superfamily which is up-regulated in cardiac diseases, in part via hypoxia-dependent mechanisms. However, no evidence for a direct regulation of CT-1 gene (CTF1) promoter by hypoxia inducible factor-1 (HIF-1) has been provided. Methods and results Hypoxia increased CT-1 mRNA levels in the murine adult cardiomyocyte cell line HL-1 in a time-dependent manner. Interestingly, in a murine model (C57BL/6), we show that systemic hypoxia also significantly up-regulated CT-1 in myocardial tissue. The effect of hypoxia on CT-1 expression was mediated through a transcriptional mechanism, since hypoxia increased luciferase activity of constructs containing CTF1 promoter sequences. The increase in CT-1 levels was significantly reduced by drugs that prevent calcium mobilization, such as lercanidipine, or that inhibit the activation of the PI3K/Akt pathway (wortmannin) or mammalian target of rapamycin (rapamycin). The CT-1 elevation was similarly induced by HIF-1 alpha over-expression in co-transfection experiments and prevented by HIF-1 alpha silencing. The direct interaction of HIF-1 alpha with the CTF1 promoter was confirmed through site-directed mutagenesis of hypoxia response elements, electrophoreric mobility shift, and ChIP assays. Hypoxia induced HL-1 apoptosis (measured as annexin-V binding or caspase 3/7 activity) which was increased when CT-1 was silenced in knocked-down cells by lentiviral vectors. Conclusion Hypoxia increased CT-1 levels in cardiac cells (in vitro and in vivo) through a direct regulation of CTF1 promoter by HIF-1 alpha. This CT-1 activation by hypoxia may protect cells from apoptosis, thus supporting a protective role for CT-1 as a survival factor for cardiomyocytes.