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Patients with the dual burden of chronic kidney disease (CKD) and chronic congestive heart failure (HF) experience unacceptably high rates of symptom load, hospitalization, and mortality. Currently, concerted efforts to identify, prevent and treat HF in CKD patients are lacking at the institutional level, with emphasis still being placed on individual specialty views on this topic. The authors of this review paper endorse the need for a dedicated cardiorenal interdisciplinary team that includes nephrologists and renal nurses and jointly manages appropriate clinical interventions across the inpatient and outpatient settings. There is a critical need for guidelines and best clinical practice models from major cardiology and nephrology professional societies, as well as for research funding in both specialties to focus on the needs of future therapies for HF in CKD patients. The implementation of cross-specialty educational programs across all levels in cardiology and nephrology will help train future specialists and nurses who have the ability to diagnose, treat, and prevent HF in CKD patients in a precise, clinically effective, and cost-favorable manner. Resumen: Los pacientes con enfermedad renal crónica (ERC) que desarrollan insuficiencia cardíaca (IC) congestiva crónica presentan cifras inaceptablemente altas de síntomas, hospitalización y mortalidad. Actualmente, se echan en falta iniciativas institucionales dirigidas a identificar, prevenir y tratar la IC en los pacientes con ERC de manera multidisciplinar, prevaleciendo las actuaciones de las especialidades individuales. Los autores de este artículo de revisión respaldan la necesidad de crear equipos multidisciplinares cardiorrenales, en los que participen nefrólogos y enfermeras renales, que gestionen colaborativamente las intervenciones clínicas apropiadas en los entornos de pacientes con ERC e IC hospitalizados y ambulatorios. Es necesario y urgente que se elaboren guías y modelos de práctica clínica sobre la ERC con IC por parte de las sociedades profesionales de cardiología y nefrología, así como financiación para la investigación concertada entre ambas especialidades sobre la necesidad de futuros tratamientos para la IC en pacientes con ERC. La implementación de programas educativos cardiorrenales a todos los niveles en cardiología y nefrología ayudará a formar a los futuros especialistas y enfermeras para que tengan la capacidad de diagnosticar, tratar y prevenir la IC en pacientes con ERC de manera precisa, clínicamente efectiva y económicamente favorable.

Diffuse myocardial fibrosis resulting from the excessive deposition of collagen fibres through the entire myocardium is encountered in a number of chronic cardiac diseases. This lesion results from alterations in the regulation of fibrillary collagen turnover by fibroblasts, facilitating the excessive deposition of type I and type III collagen fibres within the myocardial interstitium and around intramyocardial vessels. The available evidence suggests that, beyond the extent of fibrous deposits, collagen composition and the physicochemical properties of the fibres are also relevant in the detrimental effects of diffuse myocardial fibrosis on cardiac function and clinical outcomes in patients with heart failure. In this regard, findings from the past 20 years suggest that various clinicopathological phenotypes of diffuse myocardial fibrosis exist in patients with heart failure. In this Review, we summarize the current knowledge on the mechanisms and detrimental consequences of diffuse myocardial fibrosis in heart failure. Furthermore, we discuss the validity and usefulness of available imaging techniques and circulating biomarkers to assess the clinicopathological variation in this lesion and to track its clinical evolution. Finally, we highlight the currently available and potential future therapeutic strategies aimed at personalizing the prevention and reversal of diffuse myocardial fibrosis in patients with heart failure.

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 (P = 0.01) improvements for the mentioned outcome. Conclusion The combination of low serum CITP : MMP-1 ratio and high serum PICP identifies hypertensive patients with heart failure presenting with a phenotype of myocardial fibrosis characterized by the concurrence of excessive CCL and CD and associated with poor outcome.

INTRODUCTION Ultrahigh-density-voltage mapping (uHDV M) is a new tool that can add new insights into the pathophysiology of atrial fibrillation (AF). The aim of this study was to evaluate the performance of uHDV M in predicting postablation AF recurrence (AFR). METHODS AND RESULTS We included 98 consecutive patients undergoing pulmonary vein isolation for AF (40.8% persistent) using an uHDV M system and followed for 1 year. The left atrium (LA) mean voltage (Vm ) and the Vslope (slope of the voltage histogram calculated by linear interpolation, with the relative frequency on the vertical axis and the bipolar potential on the horizontal axis) were calculated from 12 567 ± 5486 points per map. Patients with AFR (N = 29) had lower Vm and higher Vslope as compared with patients without AFR (N = 69). Receiver operating characteristic curves identified Vm as the strongest predictor of AFR, with a higher incidence of AFR in patients with Vm 0.758 mV (57.6%) or lower than patients with Vm higher than 0.758 mV (15.4%; P

Myocardial fibrosis is a main contributor to the development of heart failure (HF). CT-1 (cardiotrophin-1) and Gal-3 (galectin-3) are increased in HF and associated with myocardial fibrosis. The aim of this study is to analyze whether CT-1 regulates Gal-3. Proteomic analysis revealed that Gal-3 was upregulated by CT-1 in human cardiac fibroblasts in parallel with other profibrotic and proinflammatory markers. CT-1 upregulation of Gal-3 was mediated by ERK (extracellular signal-regulated kinase) 1/2 and Stat-3 (signal transducer and activator of transcription 3) pathways. Male Wistar rats and B6CBAF1 mice treated with CT-1 (20 µg/kg per day) presented higher cardiac Gal-3 levels and myocardial fibrosis. In CT-1-treated rats, direct correlations were found between cardiac CT-1 and Gal-3 levels, as well as between Gal-3 and perivascular fibrosis. Gal-3 genetic disruption in human cardiac fibroblasts and pharmacological Gal-3 inhibition in mice prevented the profibrotic and proinflammatory effects of CT-1. Dahl salt-sensitive hypertensive rats with diastolic dysfunction showed increased cardiac CT-1 and Gal-3 expression together with cardiac fibrosis and inflammation. CT-1 and Gal-3 directly correlated with myocardial fibrosis. In HF patients, myocardial and plasma CT-1 and Gal-3 were increased and directly correlated. In addition, HF patients with high CT-1 and Gal-3 plasma levels presented an increased risk of cardiovascular death. Our data suggest that CT-1 upregulates Gal-3 which, in turn, mediates the proinflammatory and profibrotic myocardial effects of CT-1. The elevation of both molecules in HF patients identifies a subgroup of patients with a higher risk of cardiovascular mortality. The CT-1/Gal-3 axis emerges as a candidate therapeutic target and a potential prognostic biomarker in HF.

Objective— Body iron status has been linked to atherosclerosis in adults. The purposes of our study were to determine (1) the association between circulating ferritin levels and carotid intima-media thickness (cIMT) in a cohort of apparently healthy children and (2) the association between cIMT and parental ferritin levels. Approach and Results— Circulating ferritin levels (microparticle enzyme immunoassay), metabolic parameters, and cIMT (ultrasonography) were analyzed cross-sectionally in a cohort of 692 healthy white children with a mean age of 8±2 years (52% girls and 48% boys). In consecutive 123 children from the cross-sectional sample, the same serum assessments were also performed at baseline in their parents, and the cIMT was repeated after 3 years of follow-up in the children at a mean age of 11±2 years (53% girls and 47% boys). Weak but significant positive associations were evident between children’s circulating ferritin levels and cIMT ( r =0.123; P =0.001) and with the change in cIMT 3 years later a tendency was also observed ( r =0.185; P =0.048). In multiple regression analyses, circulating ferritin levels contributed independently to cIMT variance (β=0.090; P =0.026; R 2 =10%) and cIMT change variance (β=0.216; P =0.019; R 2 = 3.4%) after controlling for body mass index, high-sensitivity C-reactive protein, age, sex, and low-density lipoprotein-cholesterol levels. This association was, however, remarkably significant (β=0.509; P =0.001; R 2 = 20.4%) in children whose fathers had ferritin levels above the median value (122.5 ng/mL).The latter association remained significant after correction for multiple testing. Maternal’s ferritin levels showed no interaction in this association. Conclusions— These results suggest a paternal-specific effect on cIMT partially reflected by father’s ferritin levels.

BackgroundExcessive 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.ObjectivesThis 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.MethodsEndomyocardial 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.ResultsInvasive 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.ConclusionsExcessive 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.

The relationship between osteoprotegerin (OPG) a glycoprotein related to bone metabolism and the metabolic syndrome (MS) has not been established.The aim of this study is to evaluate OPG concentration in patients with MS and its association with subclinical atherosclerosis and coronary arterial calcification (CAC).The study included 238 asymptomatic patients. MS was diagnosed according to the NCEP/ATPIII guidelines. OPG was measured by ELISA. All subjects underwent ultrasonography of the common carotid arteries to measure intima-media thickness (IMT) and evaluate the presence of atheroma plaques. In a subgroup (n=39) CAC was quantified by ECG-triggered cardiac computed tomography. Adipose tissue was excised from 25 patients and OPG expression by RT-PCR and immunohistochemistry was studied.Patients with the MS (n=60) had higher OPG than patients without (n=178) (p0.05). OPG correlated with IMT (r=0.2, p=0.005) and patients with atheroma plaques had higher OPG (p=0.008) and also those with coronary artery calcification (p0.05). OPG expression was confirmed in adipose tissue (n=12) and the expression was significantly higher in patients with MS than in those without (p=0.003).This study shows that OPG may potentially be a biomarker for cardiovascular risk/damage in the MS and identifies adipose tissue as a potential source of OPG.

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.

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-β1-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.

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.

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.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-1α over-expression in co-transfection experiments and prevented by HIF-1α silencing. The direct interaction of HIF-1α 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.Hypoxia increased CT-1 levels in cardiac cells (in vitro and in vivo) through a direct regulation of CTF1 promoter by HIF-1α. 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.

OBJECTIVES: Hyperleptinemia and oxidative stress play a major role in the development of cardiovascular diseases in obesity. This study aimed to investigate whether there is a relationship between plasma levels of leptin and phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity, and its potential relevance in the vascular remodeling in obese patients. METHODS: The study was performed in 164 obese and 94 normal-weight individuals (controls). NADPH oxidase activity was evaluated by luminescence in phagocytic cells. Levels of leptin were quantified by ELISA in plasma samples. Carotid intima-media thickness (cIMT) was measured by ultrasonography. In addition, we performed in-vitro experiments in human peripheral blood mononuclear cells and murine macrophages. RESULTS: Phagocytic NADPH oxidase activity and leptin levels were enhanced (P < 0.05) in obese patients compared with controls. NADPH oxidase activity positively correlated with leptin in obese patients. This association remained significant in a multivariate analysis. cIMT was higher (P < 0.05) in obese patients compared with controls. In addition, cIMT also correlated positively with leptin and NADPH oxidase activity in obese patients. In-vitro studies showed that leptin induced NADPH oxidase activation. Inhibition of the leptin-induced NADPH oxidase activity by wortmannin and bisindolyl maleimide suggested a direct involvement of the phosphatidylinositol 3-kinase and protein kinase C pathways, respectively. Finally, leptin-induced NADPH oxidase activation promoted macrophage proliferation. CONCLUSIONS: These findings show that phagocytic NADPH oxidase activity is increased in obesity and is related to preclinical atherosclerosis in this condition. We also suggest that hyperleptinemia may contribute to phagocytic NADPH oxidase overactivity in obesity.

Objective Recent guidelines recommend more aggressive lipid-lowering in secondary prevention protocols. We examined whether this resulted in improved endothelial function. Methods We studied saphenous vein specimens of patients undergoing surgical coronary revascularisation in 2007 and compared results with those of patients examined in 2003. Endothelium-dependent vasodilation was assessed by relaxation to calcium ionophore A23187, and vascular superoxide production by lucigenin enhanced chemiluminescence. Results Statin dose increased from 26 ± 16 mg/d in 2003 to 37 ± 17 mg/d in 2007 (P

Increased vascular production of reactive oxygen species, especially superoxide anion, significantly contributes to the oxidative stress associated with hypertension. An enhanced superoxide production causes an increased inactivation of nitric oxide that diminishes nitric oxide bioavailability, thus contributing to endothelial dysfunction and hypertrophy of vascular cells. It has been shown that NADPH oxidases play a major role as the most important sources of superoxide anion in phagocytic and vascular cells. Several experimental observations have described an enhanced superoxide generation as a result of NADPH oxidase activation in hypertension. Although these enzymes respond to stimuli such as vasoactive factors, growth factors, and cytokines, recent data suggest a significant role of the genetic background in the modulation of the expression of its different components. Several polymorphisms have been identified in the promoter and in the coding region of CYBA, the gene that encodes the essential subunit of the NADPH oxidase p22phox, some of which seem to influence significantly the activity of these enzymes in the context of cardiovascular diseases. Among CYBA polymorphisms, genetic investigations have provided a novel marker, the -930(A/G) polymorphism, which determines the genetic susceptibility of hypertensive patients to oxidative stress.

The p22(phox) subunit is an essential protein in the activation of NAD(P)H oxidase. Here we report the preliminary characterisation of the human p22(phox) gene promoter. The p22(phox) promoter contains TATA and CCAC boxes and Sp1, gamma-interferon and nuclear factor kappaB sites. We screened for mutations in the p22(phox) promoter and identified a new polymorphism, localised at position -930 from the ATG codon, which was associated with hypertension. Mutagenesis experiments showed that the G allele had higher promoter activity than the A allele. These results suggest that the -930(A/G) polymorphism in the p22(phox) promoter may be a novel genetic marker associated with hypertension.

Increased vascular reactive oxygen species production, especially superoxide anion, contributes significantly in the functional and structural alterations present in hypertension. An enhanced superoxide production causes a diminished NO bioavailability by an oxidative reaction that inactivates NO. Exaggerated superoxide levels and a low NO bioavailability lead to endothelial dysfunction and hypertrophy of vascular cells. It has been shown that the enzyme NAD(P)H oxidase plays a major role as the most important source of superoxide anion in vascular cells. Several experimental observations have shown an enhanced superoxide generation as a result of the activation of vascular NAD(P)H oxidase in hypertension. Although this enzyme responds to stimuli such as vasoactive factors, growth factors, and cytokines, some recent data suggest the existence of a genetic background modulating the expression of its different components. New polymorphisms have been identified in the promoter of the p22 phox gene, an essential subunit of NAD(P)H oxidase, influencing the activity of this enzyme. Genetic investigations of these polymorphisms will provide novel markers for determination of genetic susceptibility to oxidative stress in hypertension.

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

Background Chronic kidney disease (CKD) and coronary artery disease (CAD) are independently associated with increased vascular stiffness. We examined whether renal function contributes to vascular stiffness independently of CAD status. Methods We studied 160 patients with CAD and 169 subjects without CAD. The 4-variable MDRD formula was used to estimate glomerular filtration rate (eGFR); impaired renal function was defined as eGFR Results Patients with CAD and impaired renal function had greater PWV compared to those with CAD and normal renal function (10.2 [9.1;11.2] vs 7.3 [6.9;7.7] m/s; P P P Conclusions Renal function is a determinant of vascular stiffness even in patients with severe atherosclerotic disease. This was paralleled by differences in markers of cell adhesion and inflammation. Increased vascular stiffness may therefore be linked to inflammatory remodeling of the vasculature in people with impaired renal function, irrespective of concomitant atherosclerotic disease.

Objective Experimental and clinical evidence supports a role of cardiotrophin-1 (CT-1) in the development of hypertensive left ventricular hypertrophy (LVH). The goal of this study was to investigate the relationship between human CT-1 genetic background and LVH in essential hypertension. Methods A total of 900 individuals were genotyped for the 1742(C/G) polymorphism of the human CT-1 gene. Serum CT-1 levels were assessed by ELISA in 681 individuals. Left ventricular parameters were determined by two-dimensional echocardiography in 297 individuals. Results The prevalence of the GG genotype of the 1742(C/G) polymorphism was reduced in essential hypertension (8.4% in normotensive individuals, 4.9% in hypertensive patients, P = 0.046 versus CC/CG individuals) and in LVH (11.5% in nonhypertrophic normotensive individuals, 12.2% in nonhypertrophic hypertensive patients, 2.6% in hypertensive patients with LVH, P = 0.008 versus CC/CG individuals). Apart from this, GG individuals presented lower serum concentration of CT-1 (GG, 147.1 ± 10.5 fmol/ml; CC/CG, 187.1 ± 4.8 fmol/ml; P = 0.036) and left ventricular mass index (GG, 91 ± 6 g/m; CC/CG, 119 ± 3 g/m; P = 0.002). Multivariate analyses showed that the 1742(C/G) polymorphism was a significant determinant of both left ventricular mass index and serum CT-1, after adjusting for confounding factors. Finally, in-vitro studies supported the functionality of the 1742(C/G) polymorphism. Conclusion Our results indicate that the 1742(C/G) polymorphism of the human CT-1 gene is associated with LVH in hypertension and that the GG genotype may have a protective role. It is suggested that CT-1 is one of the mediators of this association.

Owing to the dynamic nature of the transcriptome, gene expression profiling is a promising tool for discovery of disease-related genes and biological pathways. In the present study, we examined gene expression in whole blood of 12 patients with CAD (coronary artery disease) and 12 healthy control subjects. Furthermore, ten patients with CAD underwent whole-blood gene expression analysis before and after the completion of a cardiac rehabilitation programme following surgical coronary revascularization. mRNA and miRNA (microRNA) were isolated for expression profiling. Gene expression analysis identified 365 differentially expressed genes in patients with CAD compared with healthy controls (175 up- and 190 down-regulated in CAD), and 645 in CAD rehabilitation patients (196 up- and 449 down-regulated post-rehabilitation). Biological pathway analysis identified a number of canonical pathways, including oxidative phosphorylation and mitochondrial function, as being significantly and consistently modulated across the groups. Analysis of miRNA expression revealed a number of differentially expressed miRNAs, including hsa-miR-140-3p (control compared with CAD, P=0.017), hsa-miR-182 (control compared with CAD, P=0.093), hsa-miR-92a and hsa-miR-92b (post- compared with pre-exercise, P

Endothelial dysfunction is a marker of atherosclerosis and contributes to the atherogenic process and the development of atherothrombotic complications. Oxidative stress has been implicated in the development of endothelial dysfunction through alterations of the nitric oxide metabolism. A number of evidence suggests a role for phagocytic-cell-mediated oxidative stress in diminished nitric oxide availability that is present in patients with atherosclerotic risk factors such as arterial hypertension. Thus, the combination of an excessive production of reactive oxygen species, namely superoxide anion, with an impaired antioxidant defense capacity leading to oxidative stress may facilitate the development and progression of atherosclerosis. Findings from recent clinical studies suggest that this mechanism can be operative in patients with cerebrovascular disease. This view may increase our capabilities to understand the pathophysiology of cerebrovascular disease, as well as to stimulate the design of new therapeutic strategies aimed to prevent and control the atherosclerotic process in patients presenting this condition.

Objective— Data suggest that matrix metalloproteinase-9 (MMP-9) has a role in atherosclerosis. The phagocytic NADPH oxidase has been also associated with atherosclerosis. This study aimed to investigate the association between phagocytic NADPH oxidase and MMP-9 in human atherosclerosis. Methods and Results— In vitro experiments performed in human monocytes showed that NADPH oxidase activation enhanced MMP-9 secretion and activity, determined by enzyme-linked immunosorbent assay and zymography, respectively. Immunohistochemical study showed that phagocytic NADPH oxidase localized with MMP-9 in endarterectomies from patients with carotid stenosis. In addition, a positive relationship ( P Conclusions— Enhanced NADPH oxidase-dependent ·O 2 − production stimulates MMP-9 in monocytes and this relationship may be relevant in the atherosclerotic process. Moreover, MMP-9 emerges as an important mediator of the phagocytic NADPH oxidase-dependent oxidative stress in atherosclerosis.

OBJECTIVE: Oxidative stress is implicated in hypertension and the NADPH oxidase systems constitute the main source of superoxide in vascular wall. We searched for new polymorphisms within the CYBA promoter, the human gene that encodes the p22phox protein, and studied their potential association with essential hypertension. DESIGN: A case-control study in a random sample of the general population. METHODS: CYBA polymorphisms were determined by restriction fragment length polymorphism and allelic discrimination. NADPH oxidase activity was quantified in phagocytic cells by chemiluminescence. RESULTS: We identified three novel polymorphisms, at positions -852, -675 and -536 from the ATG codon. Only the -675(A/T) polymorphism associated with essential hypertension. The prevalence of the TT genotype and the T allele frequency were significantly higher (P < 0.05) in hypertensives than in normotensives. Furthermore, TT hypertensives exhibited higher (P < 0.05) systolic blood pressure values than TA/AA hypertensives. Increased phagocytic NADPH oxidase activity was observed in TT subjects compared to TA and AA individuals (P < 0.05). Enhanced carotid intima-media thickness, a surrogate marker of atherosclerosis, was found in TT subjects compared to TA and AA individuals (P < 0.05). Finally, mutagenesis experiments demonstrated a functional role of this polymorphism on the CYBA promoter activity. CONCLUSION: The -675 (A/T) CYBA polymorphism may be a novel genetic marker associated with essential hypertension. Furthermore, TT subjects exhibit features of NADPH oxidase-mediated oxidative stress and asymptomatic atherosclerosis.

Oxidative stress plays a critical role in the pathogenesis of atherosclerosis in patients with metabolic syndrome. This study aimed to investigate whether a relationship exists between phagocytic NADPH oxidase activity and oxidative stress and atherosclerosis in metabolic syndrome patients. The study was performed in 56 metabolic syndrome patients (metabolic syndrome group), 99 patients with one or two cardiovascular risk factors (cardiovascular risk factor group), and 28 healthy subjects (control group). NADPH oxidase expression and activity was augmented (P < 0.05) in metabolic syndrome compared with cardiovascular risk factor and control groups. Insulin was enhanced (P < 0.05) in metabolic syndrome patients compared with cardiovascular risk factor and control groups and correlated with NADPH oxidase activity in the overall population. Insulin stimulated NADPH oxidase activity; this effect was abolished by a specific protein kinase C inhibitor. Oxidized LDL and nitrotyrosine levels and carotid intima-media thickness were increased (P < 0.05) in the metabolic syndrome group compared with cardiovascular risk factor and control groups and correlated with NADPH oxidase activity in the overall population. These findings suggest that phagocytic NADPH oxidase overactivity is involved in oxidative stress and atherosclerosis in metabolic syndrome patients. Our findings also suggest that hyperinsulinemia may contribute to oxidative stress in metabolic syndrome patients through activation of NADPH oxidase.

OBJECTIVE: Oxidative stress is implicated in hypertension. The reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidases are the main source of superoxide in phagocytic and vascular cells. The C242T polymorphism of CYBA, the human gene that encodes p22phox, has been found to be functionally associated with vascular NADPH oxidase activity in atherosclerotic patients. We investigated the association of the C242T polymorphism with hypertension and its potential impact on NADPH oxidase activity. We also analysed the interaction of C242T polymorphism with the -930A/G CYBA variant. DESIGN: Case-control study in a random sample of 623 subjects (326 hypertensive patients and 297 normotensive controls) from the general population. METHODS: CYBA polymorphisms were determined by restriction fragment length polymorphism (RFLP) or allelic discrimination. NADPH oxidase activity and p22phox expression were quantified in phagocytic cells by chemiluminescence and by northern and western blots, respectively. RESULTS: The prevalence of the CC genotype and the C allele frequency were significantly higher (P < 0.05) in hypertensives than in normotensives. CC genotype remained associated with hypertension after adjusting for potential confounders in a logistic regression analysis. Increased phagocytic NADPH oxidase activity was observed in CC hypertensives compared with CT and TT hypertensives (P < 0.05). Enhanced plasma levels of von Willebrand factor were found in CC hypertensives compared with TT hypertensives (P < 0.05). The C242T polymorphism was not in linkage disequilibrium with the -930A/G CYBA promoter variation, which also associates with hypertension. CONCLUSION: The C242T CYBA polymorphism is associated with essential hypertension. Furthermore, hypertensives carrying the CC genotype of this polymorphism exhibit features of NADPH oxidase-mediated oxidative stress and endothelial damage.

Background. Oxidative stress has been implicated in the pathogenesis of atherosclerosis that develops in patients with advanced chronic kidney disease (CKD). This study was designed to investigate whether a relationship exists between phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase–dependent superoxide anion (•O2 −) production and subclinical atherosclerosis in patients with early CKD. Methods. Superoxide production was assayed by chemiluminescence under baseline and stimulated conditions on mononuclear cells obtained from asymptomatic patients with stage 1 to 2 CKD (N = 22) and healthy controls (N = 21). Ultrasonographic determination of carotid intima-media thickness (IMT) was used to assess the presence of atherosclerosis. Results. Although there were no differences in baseline •O2 − production between controls and patients, the •O2 − production in phorbol myristate acetate–stimulated mononuclear cells was increased (P < 0.05) in patients compared with controls. The phorbol myristate acetate–induced •O2 − production was completely abolished by apocynin, a specific inhibitor of NADPH oxidase. A direct correlation (r = 0.441, P < 0.05) was found between plasma insulin levels and NADPH oxidase–mediated •O2 − production in patients. Carotid IMT was higher (P < 0.005) in patients than in controls. CarotidIMTvalues above the upper normal limit in controls were found in 70% and 40% of patients with increased or normal NADPH oxidase–mediated •O2 − production, respectively. Conclusion. Generation of •O2 − that is mainly dependent on NADPH oxidase is abnormally enhanced in patients with early CKD. It is suggested that this alteration could be related to the development of subclinical atherosclerosis in these patients.

Oxidative stress plays an important role in the pathophysiology of vascular diseases. Reactive oxygen species, especially superoxide anion and hydrogen peroxide, are important signalling molecules in cardiovascular cells. Enhanced superoxide production increases nitric oxide inactivation and leads to an accumulation of peroxynitrites and hydrogen peroxide. Reactive oxygen species participate in growth, apoptosis and migration of vascular smooth muscle cells, in the modulation of endothelial function, including endothelium-dependent relaxation and expression of proinflammatory phenotype, and in the modification of the extracellular matrix. All these events play important roles in vascular diseases such as hypertension, suggesting that the sources of reactive oxygen species and the signalling pathways that they modify may represent important therapeutic targets. Potential sources of vascular superoxide production include NADPH-dependent oxidases, xanthine oxidases, lipoxygenases, mitochondrial oxidases and nitric oxide synthases. Studies performed during the last decade have shown that NADPH oxidase is the most important source of superoxide anion in phagocytic and vascular cells. Evidence from experimental animal and human studies suggests a significant role of NADPH oxidase activation in the vascular remodelling and endothelial dysfunction found in cardiovascular diseases.

Objective— Oxidative stress plays a critical role in the pathogenesis of atherosclerosis. The NADPH oxidase constitutes the main source of superoxide in phagocytic and vascular cells. This study aimed to investigate the levels of NADPH oxidase–mediated superoxide production in phagocytic cells and the association between phagocytic superoxide production and carotid intima-media thickness (IMT), a surrogate marker of asymptomatic atherosclerosis. Methods and Results— NADPH oxidase–mediated superoxide production was determined by a chemiluminescence assay using lucigenin and associated with IMT for 184 asymptomatic subjects free of overt clinical atherosclerotic disease. Compared with individuals in the lowest tertile of superoxide production, those in the upper tertile (>20 counts/sec) showed significantly higher IMT ( P P Conclusions— In a population sample of adults without clinically overt atherosclerotic disease, increased NADPH oxidase activity was associated with enhanced carotid IMT, suggesting a relationship between phagocytic NADPH oxidase–mediated oxidative stress and the development of atherosclerosis.

Objective: Oxidative stress has been implicated in the pathogenesis of hypertension and its complications through alterations in nitric oxide (NO) metabolism. This study was designed to investigate whether a relationship exists between phagocytic nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-dependent superoxide anion (•O2-) production and NO generation in patients with essential hypertension. Methods: Superoxide production was assayed by chemiluminescence under baseline and stimulated conditions on mononuclear cells obtained from hypertensives (n = 51) and normotensives (n = 43). NO production was evaluated by determining serum NO metabolites, nitrate plus nitrite (NOx). Results: Although there were no differences in baseline •O2- production between normotensives and hypertensives, the •O2- production in phorbol myristate acetate (PMA)-stimulated mononuclear cells was increased (P < 0.05) in hypertensives compared with normotensives. The PMA-induced •O2- production was completely abolished by apocynin, a specific inhibitor of NADPH oxidase. Moreover, stimulation of •O2- production by angiotensin II and endothelin-1 was higher (P < 0.05) in cells from hypertensives than in cells from normotensives. In addition, diminished (P < 0.001) serum NOx was detected in hypertensives compared with normotensives. Interestingly, an inverse correlation (r = 0.493, P < 0.01) was found between •O2- production and NOx in hypertensives. Conclusions: Generation of •O2- mainly dependent on NADPH oxidase is abnormally enhanced in stimulated mononuclear cells from hypertensives. It is suggested that this alteration could be involved in the diminished NO production observed in these patients.

Oxidative stress induced by superoxide is implicated in hypertension. NADPH oxidase is the main source of superoxide in phagocytic and vascular cells, and the p22phox subunit is involved in NADPH oxidase activation. Recently we reported an association of -930A/G polymorphism in the human p22phox gene promoter with hypertension. This study was designed to investigate the functional role of this polymorphism in hypertension. We thus investigated the relationships between the -930A/G polymorphism and p22phox expression and NADPH oxidase-mediated superoxide production in phagocytic cells from 70 patients with essential hypertension and 70 normotensive controls. Genotyping of the polymorphism was performed by restriction fragment length polymorphism. NADPH oxidase activity was determined by chemiluminescence assays, and p22phox mRNA and protein expression was measured by Northern and Western blotting, respectively. Compared with hypertensive subjects with the AA/AG genotype, hypertensive subjects with the GG genotype exhibited increased (P0.05) phagocytic p22phox mRNA (1.26+/-0.06 arbitrary unit [AU] versus 0.99+/-0.03 AU) and protein levels (0.58+/-0.05 AU versus 0.34+/-0.04 AU) and enhanced NADPH oxidase activity (1998+/-181 counts/s versus 1322+/-112 counts/s). No differences in these parameters were observed among genotypes in normotensive cells. Transfection experiments on vascular smooth muscle cells showed that the A-to-G substitution of this polymorphism produced an increased reporter gene expression in hypertensive cells. Nitric oxide production, as assessed by measurement of serum nitric oxide metabolites, was lower in GG hypertensive subjects than in AA/AG hypertensive subjects. In conclusion, these results suggest that hypertensive subjects carrying the GG genotype of the p22phox -930A/G polymorphism are highly exposed to NADPH oxidase-mediated oxidative stress.

The objective of the present study was to analyse the influence of the ACE (angiotensin-converting enzyme) gene I/D (insertion/deletion) polymorphism on NADPH oxidase-dependent O2•− (superoxide radical) production, and to investigate the clinical implication of this association in hypertensive subjects. A case-control study was performed in a random sample of the general population composed of 189 normotensive subjects and 223 hypertensive subjects. The ACE polymorphism was determined by PCR. NADPH oxidase-dependent O2•− production was quantified in phagocytic cells by chemiluminescence. MMP-9 (matrix metalloproteinase-9), a marker of atherosclerosis previously reported to be associated with NADPH oxidase overactivity, was quantified by ELISA in plasma samples. The distribution of genotypes was in Hardy–Weinberg equilibrium. The I/D polymorphism was not associated with hypertension. NADPH oxidase-dependent O2•− production was significantly higher in D/D (deletion/deletion) than in I/I (insertion/insertion) and I/D, both in normotensive and hypertensive subjects. Interestingly, plasma levels of angiotensin II were significantly higher in D/D than in I/I and I/D, both in normotensive and hypertensive subjects. Plasma levels of MMP-9 and systolic blood pressure values were significantly higher in D/D than in I/I and I/D hypertensive subjects, whereas no differences were found among genotypes in normotensive subjects. Interestingly, NADPH oxidase-dependent O2•− production positively associated with plasma MMP-9 levels in hypertensive subjects, which remained significant after adjustment for age and gender. In conclusion, in the present study we have reported for the first time an association of the D/D genotype of the ACE I/D polymorphism with phagocytic NADPH oxidase-mediated O2•− overproduction. Within the group of hypertensive patients, D/D cases also associated with increased blood pressure values and with enhanced plasma levels of MMP-9. Abbreviations: ACE, angiotensin-converting enzyme; ACEi, ACE inhibitor(s); AngII, angiotensin II; AngI, angiotensin I; ARA, AngII type 1-receptor antagonist; BMI, body mass index; BP, blood pressure; DBP, diastolic BP; D/D, deletion/deletion; I/D, insertion/deletion; I/I, insertion/insertion; IMT, intima-media thickness; IL-6, interleukin-6; MMP-9, matrix metalloproteinase-9; O2•−, superoxide radical; SBP, systolic BP

Oxidative stress plays a key role in the pathophysiology of coronary artery disease, and constitutes a common mechanism behind the risk factors associated with this disease such as atherosclerosis, hypertension, diabetes and the metabolic syndrome. Oxidative stress is defined as an imbalance between the production of reactive oxygen and nitrogen species and the detoxification by the appropriate cellular systems. Reactive oxygen species induce cardiovascular dysfunction by modulating cell contraction/dilation, migration, growth/apoptosis and extracellular matrix protein turnover, which contribute to vascular and cardiac remodeling. In the last decade, the NADPH oxidase family has emerged as one of the most relevant sources of reactive oxygen species within the cardiovascular system. Recent data suggest a significant role of the genetic background in NADPH oxidase regulation. Common genetic polymorphisms within the promoter and exonic sequences of CYBA, the gene that encodes the p22phox subunit of the NADPH oxidase, have been characterized in the context of cardiovascular diseases. This review aims to present the current state of research into these polymorphisms with regards to their relationship to coronary artery disease.

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.

Overweight and obesity related metabolic disorders, commonly sharing a pathogenic excess of body adiposity, are world-wide epidemic leading to increasing morbidity and mortality. The related conditions include, among the others, liver steatosis, insulin resistance, and cardiovascular risk. Effective and safe anti-obesity drugs are still needed. Likely without undesirable side effects, an ideal treatment should be able to counteract the numerous causes associated with excess of body adiposity putatively modulating the delicate balance between feeding and energy expenditure, untimely controlling the adipose mass. In the past, thyroid hormones have been tested in reducing weight and lipid accumulation, however, the concomitant induction of a thyrotoxicosis state limited their use. Recent studies in rodents revealed that 3,5- diiodo-L-thyronine (T2), an endogenous metabolite of thyroid hormones, exhibits interesting metabolic activities. Specifically, when exogenously administered, T2 increases the resting metabolic rate and elicits short-term beneficial hypolipidemic effects, without being thyrotoxic, at lest in high fat diet fed rats. Now, a matter of interest is whether T2 can be considered or not a potential anti-obesity pharmacological agent. Actually, very few studies have been performed as far as it concerns the effects of T2 in humans and further analyses on larger cohorts to test time of use- and dose-dependent actions as well as the putative occurrence of T2 induced undesirable side effects, are needed. Here, an updated overview of the current literature on T2 bioactivity is furnished with a particular focus on those effects which may be defined "beneficial" vs. "deleterious" ones above all in view of its putative pharmacological use.