Peripheral arterial disease (PAD) is associated with a high risk of cardiovascular events and death and is postulated to be a critical socioeconomic cost in the future. Extracellular vesicles (EVs) have emerged as potential candidates for new biomarker discovery related to their protein and nucleic acid cargo. In search of new prognostic and therapeutic targets in PAD, we determined the prothrombotic activity, the cellular origin and the transcriptomic profile of circulating EVs. This prospective study included control and PAD patients. Coagulation time (Procoag-PPL kit), EVs cellular origin and phosphatidylserine exposure were determined by flow cytometry in platelet-free plasma (n = 45 PAD). Transcriptomic profiles of medium/large EVs were generated using the MARS-Seq RNA-Seq protocol (n = 12/group). The serum concentration of the differentially expressed gene S100A9, in serum calprotectin (S100A8/A9), was validated by ELISA in control (n = 100) and PAD patients (n = 317). S100A9 was also determined in EVs and tissues of human atherosclerotic plaques (n = 3). Circulating EVs of PAD patients were mainly of platelet origin, predominantly Annexin V positive and were associated with the procoagulant activity of platelet-free plasma. Transcriptomic analysis of EVs identified 15 differentially expressed genes. Among them, serum calprotectin was elevated in PAD patients (p < 0.05) and associated with increased amputation risk before and after covariate adjustment (mean follow-up 3.6 years, p < 0.01). The combination of calprotectin with hs-CRP in the multivariate analysis further improved risk stratification (p < 0.01). Furthermore, S100A9 was also expressed in femoral plaque derived EVs and tissues. In summary, we found that PAD patients release EVs, mainly of platelet origin, highly positive for AnnexinV and rich in transcripts related to platelet biology and immune responses. Amputation risk prediction improved with calprotectin and was significantly higher when combined with hs-CRP. Our results suggest that EVs can be a promising component of liquid biopsy to identify the molecular signature of PAD patients.

Aims/hypothesis Evidence that glucose-dependent insulinotropic peptide (GIP) and/or the GIP receptor (GIPR) are involved in cardiovascular biology is emerging. We hypothesised that GIP has untoward effects on cardiovascular biology, in contrast to glucagon-like peptide 1 (GLP-1), and therefore investigated the effects of GIP and GLP-1 concentrations on cardiovascular disease (CVD) and mortality risk. Methods GIP concentrations were successfully measured during OGTTs in two independent populations (Malmo Diet Cancer-Cardiovascular Cohort [MDC-CC] and Prevalence, Prediction and Prevention of Diabetes in Botnia [PPP-Botnia]) in a total of 8044 subjects. GLP-1 (n = 3625) was measured in MDC-CC. The incidence of CVD and mortality was assessed via national/regional registers or questionnaires. Further, a two-sample Mendelian randomisation (2SMR) analysis between the GIP pathway and outcomes (coronary artery disease [CAD] and myocardial infarction) was carried out using a GIP-associated genetic variant, rs1800437, as instrumental variable. An additional reverse 2SMR was performed with CAD as exposure variable and GIP as outcome variable, with the instrumental variables constructed from 114 known genetic risk variants for CAD. Results In meta-analyses, higher fasting levels of GIP were associated with risk of higher total mortality (HR[95% CI] = 1.22 [1.11, 1.35]; p = 4.5 x 10(-5)) and death from CVD (HR[95% CI] 1.30 [1.11, 1.52]; p = 0.001). In accordance, 2SMR analysis revealed that increasing GIP concentrations were associated with CAD and myocardial infarction, and an additional reverse 2SMR revealed no significant effect of CAD on GIP levels, thus confirming a possible effect solely of GIP on CAD. Conclusions/interpretation In two prospective, community-based studies, elevated levels of GIP were associated with greater risk of all-cause and cardiovascular mortality within 5-9 years of follow-up, whereas GLP-1 levels were not associated with excess risk. Further studies are warranted to determine the cardiovascular effects of GIP per se.

Myocardial interstitial fibrosis is a constant pathological finding in structural heart diseases of various etiologies that evolve with heart failure. Although fibrosis facilitates heart failure progression, until now no therapeutic strategy has been developed that ensures its reversal. A possible explanation for this may lie in the vision of myocardial interstitial fibrosis as a homogeneous lesion instead of a heterogeneous lesion in which different phenotypes can be distinguished using appropriate criteria. In addition, the notion that the heterogeneity of myocardial interstitial fibrosis may be cardiac disease-specific must be also considered when approaching this entity. Therefore, we propose that myocardial interstitial fibrosis represents a true challenge for transitioning from usual care to biomarker-based personalized treatment and precision medicine in heart failure. As a proof-of-concept, in this review we discuss the phenotyping of myocardial interstitial fibrosis in patients with heart failure attributable to hypertensive heart disease based on its histomolecular alterations and provide evidence of the prognostic relevance of the resulting stratification. Furthermore, we discuss the available information on some circulating biomarkers and certain pharmacological agents useful for noninvasive identification and personalized treatment, respectively, of those phenotypes. (C) 2019 Sociedad Espanola de Cardiologia. Published by Elsevier Espana, S.L.U.

Background: Myocardial fibrosis is a hallmark of cardiac remodeling and functionally involved in heart failure development, a leading cause of deaths worldwide. Clinically, no therapeutic strategy is available that specifically attenuates maladaptive responses of cardiac fibroblasts, the effector cells of fibrosis in the heart. Therefore, our aim was to develop novel antifibrotic therapeutics based on naturally derived substance library screens for the treatment of cardiac fibrosis. Methods: Antifibrotic drug candidates were identified by functional screening of 480 chemically diverse natural compounds in primary human cardiac fibroblasts, subsequent validation, and mechanistic in vitro and in vivo studies. Hits were analyzed for dose-dependent inhibition of proliferation of human cardiac fibroblasts, modulation of apoptosis, and extracellular matrix expression. In vitro findings were confirmed in vivo with an angiotensin II-mediated murine model of cardiac fibrosis in both preventive and therapeutic settings, as well as in the Dahl salt-sensitive rat model. To investigate the mechanism underlying the antifibrotic potential of the lead compounds, treatment-dependent changes in the noncoding RNAome in primary human cardiac fibroblasts were analyzed by RNA deep sequencing. Results: High-throughput natural compound library screening identified 15 substances with antiproliferative effects in human cardiac fibroblasts. Using multiple in vitro fibrosis assays and stringent selection algorithms, we identified the steroid bufalin (from Chinese toad venom) and the alkaloid lycorine (from Amaryllidaceae species) to be effective antifibrotic molecules both in vitro and in vivo, leading to improvement in diastolic function in 2 hypertension-dependent rodent models of cardiac fibrosis. Administration at effective doses did not change plasma damage markers or the morphology of kidney and liver, providing the first toxicological safety data. Using next-generation sequencing, we identified the conserved microRNA 671-5p and downstream the antifibrotic selenoprotein P1 as common effectors of the antifibrotic compounds. Conclusions: We identified the molecules bufalin and lycorine as drug candidates for therapeutic applications in cardiac fibrosis and diastolic dysfunction.

Introduction Ultrahigh-density-voltage mapping (uHD(V)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 uHD(V)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 uHD(V)M system and followed for 1 year. The left atrium (LA) mean voltage (V-m) and the V-slope (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 V-m and higher V-slope as compared with patients without AFR (N = 69). Receiver operating characteristic curves identified V-m as the strongest predictor of AFR, with a higher incidence of AFR in patients with V-m 0.758 mV (57.6%) or lower than patients with V-m higher than 0.758 mV (15.4%; P < .0001). Among patients with V-m higher than 0.758 mV, patients with V-slope 0.637 or higher exhibited higher (P = .043) AFR incidence (31.3%) than patients with V-slope lower than 0.637 (10.2%). This classification showed incremental predictive value over relevant covariables. V-m values were lower and V-slope values were higher in patients that progressed from paroxysmal to persistent AF. Patients with V-slope 0.637 or higher had a 14.2% incidence of postablation atypical atrial flutter, whereas patients with V-slope lower than 0.637 did not present this outcome. Conclusions The risk of AFR, atrial flutter, and progression from paroxysmal to persistent AF can be detected by quantitative analysis of LA uHD(V)M identifying diverse patterns of atrial substrate alterations.

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 mu g/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.

BACKGROUND The mitochondrial unfolded protein response (UPRmt) is activated when misfolded proteins accumulate within mitochondria and leads to increased expression of mitochondrial chaperones and proteases to maintain protein quality and mitochondrial function. Cardiac mitochondria are essential for contractile function and regulation of cell viability, while mitochondrial dysfunction characterizes heart failure. The role of the UPRmt in the heart is unclear. OBJECTIVES The purpose of this study was to: 1) identify conditions that activate the UPRmt in the heart; and 2) study the relationship among the UPRmt, mitochondrial function, and cardiac contractile function. METHODS Cultured cardiac myocytes were subjected to different stresses in vitro. Mice were subjected to chronic pressure overload. Tissues and blood biomarkers were studied in patients with aortic stenosis. RESULTS Diverse neurohumoral or mitochondrial stresses transiently induced the UPRmt in cultured cardiomyocytes. The UPRmt was also induced in the hearts of mice subjected to chronic hemodynamic overload. Boosting the UPRmt with nicotinamide riboside (which augments NAD(+) pools) in cardiomyocytes in vitro or hearts in vivo significantly mitigated the reductions in mitochondrial oxygen consumption induced by these stresses. In mice subjected to pressure overload, nicotinamide riboside reduced cardiomyocyte death and contractile dysfunction. Myocardial tissue from patients with aortic stenosis also showed evidence of UPRmt activation, which correlated with reduced tissue cardiomyocyte death and fibrosis and lower plasma levels of biomarkers of cardiac damage (high-sensitivity troponin T) and dysfunction (N-terminal pro-B-type natriuretic peptide). CONCLUSIONS These results identify the induction of the UPRmt in the mammalian (including human) heart exposed to pathological stresses. Enhancement of the UPRmt ameliorates mitochondrial and contractile dysfunction, suggesting that it may serve an important protective role in the stressed heart. (C) 2019 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation.

Background Serial imaging studies in the general population remain important to evaluate the usefulness of pathophysiologically relevant biomarkers in predicting progression of left ventricular (LV) remodeling and dysfunction. Here, we assessed in a general population whether these circulating biomarkers at baseline predict longitudinal changes in LV structure and function. Methods and Results In 592 participants (mean age, 50.8 years; 51.4% women; 40.5% hypertensive), we derived echocardiographic indexes reflecting LV structure and function at baseline and after 4.7 years. At baseline, we measured alkaline phosphatase, markers of collagen turnover (procollagen type I, C-terminal telopeptide, matrix metalloproteinase-1) and high-sensitivity cardiac troponin T. We regressed longitudinal changes in LV indexes on baseline biomarker levels and reported standardized effect sizes as a fraction of the standard deviation of LV change. After full adjustment, a decline in LV longitudinal strain (-14.2%) and increase in E/e' ratio over time (+18.9%; P¿0.019) was associated with higher alkaline phosphatase activity at baseline. Furthermore, longitudinal strain decreased with higher levels of collagen I production and degradation at baseline (procollagen type I, -14.2%; C-terminal telopeptide, -16.4%; P¿0.029). An increase in E/e' ratio over time was borderline associated with lower matrix metalloproteinase-1 (+9.8%) and lower matrix metalloproteinase-1/tissue inhibitor of metalloproteinase-1 ratio (+11.9%; P¿0.041). Higher high-sensitivity cardiac troponin T levels at baseline correlated significantly with an increase in relative wall thickness (+23.1%) and LV mass index (+18.3%) during follow-up ( P¿0.035). Conclusions We identified a set of biomarkers predicting adverse changes in LV structure and function over time. Circulating biomarkers reflecting LV stiffness, injury, and collagen composition might improve the identification of subjects at risk for subclinical cardiac maladaptation.

The plasma levels of long noncoding RNA LIPCAR are elevated in heart failure (HF) patients with reduced ejection fraction and associated with left ventricular remodeling and poor outcomes. We studied whether the presence of chronic kidney disease (CKD), as defined by an estimated glomerular filtration rate value <60mL/(min·1.73m2) modified the associations of plasma LIPCAR with left ventricular remodeling and outcomes in HF patients. Two hundred and thirty-four patients (mean age 74 [9.14] years, 50% male) were enrolled and followed for 4.73 (0.24-7.25) years. Plasma LIPCAR was detected by real-time quantitative polymerase chain reaction. LIPCAR was increased ( P=0.005) in patients compared with 17 age- and sex-matched controls, directly correlated with age ( P=0.001) and with the maximal early transmitral flow velocity to the mean peak early diastolic velocity of the mitral annulus displacement ratio ( P=0.001) and inversely correlated with estimated glomerular filtration rate ( P<0.001). LIPCAR was associated with hospitalization for HF, cardiovascular death, and a composite of hospitalization for HF or cardiovascular death ( P¿0.010), these associations being dependent of estimated glomerular filtration rate. The interactions between estimated glomerular filtration rate and LIPCAR with respect to these outcomes were statistically significant or of borderline significance ( P¿0.060). LIPCAR was increased in CKD patients compared with non-CKD patients ( P=0.021). LIPCAR was independently associated with hospitalization for HF ( P¿0.039) only in non-CKD patients, but its addition to traditional risk factors did not improve risk prediction in these patients. In conclusion, plasma LIPCAR prognosticates outcomes in elderly HF patients without CKD. Thus, there is an effect modification of CKD on the association of circulating LIPCAR with outcomes in HF patients.

Background A combination of circulating biomarkers associated with excessive myocardial collagen type-I cross-linking or CCL+ (i.e., decreased carboxy-terminal telopeptide of collagen type-I to matrix metalloproteinase-1 ratio) and with excessive myocardial collagen type-I deposition or CD+ (i.e., increased carboxy-terminal propeptide of procollagen type-I) has been described in heart failure (HF) patients and associates with poor outcomes. Objectives The purpose of this study was to investigate whether the CCL+CD+ combination of biomarkers associates with atrial fibrillation (AF). Methods Biomarkers were analyzed in serum samples from 242 HF patients (study 1) and 150 patients referred for AF ablation (study 2). Patients were classified into 3 groups (CCL¿CD¿, CCL+CD¿ or CCL¿CD+, and CCL+CD+) in accordance to biomarker threshold values. Left atrial electroanatomic high-density mapping was performed in 71 patients from study 2. Results In study 1, 53.7% patients had AF at baseline and 19.6% developed AF (median follow-up 5.5 years). Adjusted odds and hazard ratios associated with baseline and new-onset AF, respectively, were both ¿3.3 (p ¿ 0.050) in CCL+CD+ patients compared with CCL¿CD¿ patients, with nonsignificant changes in the other group. In study 2, 29.3% patients had AF recurrence during 1-year post-ablation.

Peripheral artery disease (PAD) is a major cause of acute and chronic illness, with extremely poor prognosis that remains underdiagnosed and undertreated. Trimethylamine-N-Oxide (TMAO), a gut derived metabolite, has been associated with atherosclerotic burden. We determined plasma levels of TMAO by mass spectrometry and evaluated their association with PAD severity and prognosis. 262 symptomatic PAD patients (mean age 70 years, 87% men) categorized in intermittent claudication (IC, n = 147) and critical limb ischemia (CLI, n = 115) were followed-up for a mean average of 4 years (min 1-max 102 months). TMAO levels were increased in CLI compared to IC (P < 0.001). Receiver operating characteristic (ROC) curves for severity (CLI) rendered a cutoff of 2.26 mu mol/L for TMAO (62% sensitivity, 76% specificity). Patients with TMAO > 2.26 mu mol/L exhibited higher risk of cardiovascular death (sub-hazard ratios >= 2, P < 0.05) that remained significant after adjustment for confounding factors. TMAO levels were associated to disease severity and CV-mortality in our cohort, suggesting an improvement of PAD prognosis with the measurement of TMAO. Overall, our results indicate that the intestinal bacterial function, together with the activity of key hepatic enzymes for TMA oxidation (FMO3) and renal function, should be considered when designing therapeutic strategies to control gut-derived metabolites in vascular patients.

Background Myocardial fibrosis is characterized by excessive cross-linking and deposition of collagen type I and is involved in left ventricular stiffening and left ventricular diastolic dysfunction (LVDD). We investigated whether the effect of spironolactone on LVDD in patients with heart failure with preserved ejection fraction (HFpEF) depends on its effects on collagen cross-linking and/or deposition. Methods and results We investigated 381 HFpEF patients from the multicentre, randomized, placebo-controlled Aldo-DHF trial with measures of the E:e' ratio. The ratio of serum carboxy-terminal telopeptide of collagen type I to serum matrix metalloproteinase-1 (CITP:MMP-1, an inverse index of myocardial collagen cross-linking) and serum carboxy-terminal propeptide of procollagen type I (PICP, a direct index of myocardial collagen deposition) were determined at baseline and after 1-year treatment with spironolactone 25 mg once daily or placebo. Patients were classified by CITP: MMP-1 and PICP tertiles at baseline. While CITP: MMP-1 tertiles at baseline interacted (P < 0.05) with spironolactone effect on E:e', PICP tertiles did not. In fact, while spironolactone treatment did not modify E:e' in patients with lower CITP: MMP-1 levels, this ratio was significantly reduced in the remaining spironolactone-treated patients. In addition, PICP was unchanged in patients with lower CITP: MMP-1 levels but was reduced in the remaining spironolactone-treated patients. Conclusions A biochemical phenotype of high collagen cross-linking identifies HFpEF patients resistant to the beneficial effects of spironolactone on LVDD. It is suggested that excessive collagen cross-linking, which stabilizes collagen type I fibres, diminishes the ability of spironolactone to reduce collagen deposition in these patients.

Regulatory T (T-reg) cells offer new therapeutic options for controlling undesired systemic and local immune responses. The aim of the current study was to determine the impact of therapeutic T-reg administration on systemic and cardiac inflammation and remodeling in coxsackievirus B3 (CVB3) -induced myocarditis. Therefore, syngeneic T-reg cells were applied intravenously in CVB3-infected mice 3 d after infection. Compared with CVB3 + PBS mice, CVB3 + T-reg mice exhibited lower left ventricle (LV) chemokine expression, accompanied by reduced cardiac presence of proinflammatory Ly6C(high)CCR2(high)Cx3Cr1(low) monocytes and higher retention of proinflammatory Ly6C(mid)CCR2(high)Cx3Cr1(low) monocytes in the spleen. In addition, splenic myelopoiesis was reduced in CVB3 + T-reg compared with CVB3 + PBS mice. Coculture of T-reg cells with splenocytes isolated from mice 3 d post-CVB3 infection further demonstrated the ability of T-reg cells to modulate monocyte differentiation in favor of the anti-inflammatory Ly6C(low)CCR2(low)Cx3Cr1(high) subset. T-reg-mediated immunomodulation was paralleled by lower collagen 1 protein expression and decreased levels of soluble and insoluble collagen in LV of CVB3 + T-reg compared with CVB3 + PBS mice. In agreement with these findings, LV systolic and diastolic function was improved in CVB3 + T-reg mice compared with CVB3 + PBS mice. In summary, adoptive T-reg transfer in the inflammatory phase of viral-induced myocarditis protects the heart against inflammatory damage and fibrosis via modulation of monocyte subsets.Pappritz, K., Savvatis, K., Miteva, K., Kerim, B., Dong, F., Fechner, H., Muller, I., Brandt, C., Lopez, B., Gonzalez, A., Ravassa, S., Klingel, K., Diez, J., Reinke, P., Volk, H.-D., Van Linthout, S., Tschope, C. Immunomodulation by adoptive regulatory T-cell transfer improves Coxsackievirus B3-induced myocarditis.

Aim Heart failure with preserved ejection fraction (HFpEF) is associated with myocardial remodelling including severe pro-fibrotic changes contributing to an increase in left ventricular stiffness and diastolic dysfunction. Serum C-terminal propeptide of procollagen type I (PIP) strongly correlates with the turnover of extracellular cardiac matrix proteins and fibrosis. Torasemide, but not furosemide, was described to reduce collagen type I synthesis in clinically unstable patients with heart failure with reduced ejection fraction. We evaluated whether its effect translated to HFpEF patients with type 2 diabetes mellitus (T2DM) and abnormal basal PIP levels. Methods and results We performed a relatively small, single-centre, randomised, double-blind, two-arm parallel-group, active controlled clinical trial in 35 HFpEF patients with T2DM to determine the effects of a 9-month treatment with torasemide vs. furosemide on changes of serum PIP levels. Patients with increased PIP levels (>= 110 ng/mL), or evidence of structural changes with a left atrial volume index (LAVI) > 29 mL/m(2) and abnormal PIP levels (>= 70 ng/mL), were eligible to participate. Fifteen patients were female (42%), mean age was 69 years, body mass index was 34.7 kg/m(2), 83% were in New York Heart Association class II/III. Echocardiographic characteristics showed a mean left ventricular ejection fraction of > 60%, a left ventricular mass index > 120 g/m(2), an E/e' ratio of 14, and a LAVI of 40 mL/m(2) ...

Aims To investigate myocardial fibrosis (MF) in a large series of severe aortic stenosis (AS) patients using invasive biopsy and non-invasive imaging. Methods and results One hundred thirty-three patients with severe, symptomatic AS accepted for surgical aortic valve replacement underwent cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) and extracellular volume fraction (ECV) quantification. Intra-operative left ventricular (LV) biopsies were performed by needle or scalpel, yielding tissue with (n = 53) and without endocardium (n=80), and compared with 10 controls. Myocardial fibrosis occurred in three patterns: (i) thickened endocardium with a fibrotic layer; (ii) microscopic scars, with a subendomyo-cardial predominance; and (iii) diffuse interstitial fibrosis. Collagen volume fraction (CVF) was elevated (P<0.001) compared with controls, and higher (P<0.001) in endocardium-containing samples with a decreasing CVF gradient from the subendocardium (P = 0.001). Late gadolinium enhancement correlated with CVF (P<0.001) but not ECV. Both LGE and ECV correlated independently (P<0.001) with N-terminal pro-brain natriuretic peptide and high-sensitivity-troponin T. High ECV was also associated with worse LV remodelling, left ventricular ejection fraction and functional capacity. Combining high ECV and LGE better identified patients with more adverse LV remodelling, blood biomarkers and histological parameters, and worse functional capacity than each parameter alone. Conclusion Myocardial fibrosis in severe AS is complex, but three main patterns exist: endocardial fibrosis, microscars (mainly in the subendomyocardium), and diffuse interstitial fibrosis. Neither histological CVF nor the CMR parameters ECV and LGE capture fibrosis in its totality. A combined, multi-parametric approach with ECV and LGE allows best stratification of AS patients according to the response of the myocardial collagen matrix.

Introduction: Sequencing peptides included in the urinary proteome identifies the parent proteins and may reveal mechanisms underlying the pathophysiology of chronic kidney disease. Methods: In 805 randomly recruited Flemish individuals (50.8% women; mean age, 51.1 years), we determined the estimated glomerular filtration rate (eGFR) from serum creatinine using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. We categorized eGFR according to the National Kidney Foundation Kidney Disease Outcomes Quality Initiative guideline. We analyzed 74 sequenced urinary peptides with a detectable signal in more than 95% of participants. Follow-up measurements of eGFR were available in 597 participants. Results: In multivariable analyses, baseline eGFR decreased (P <= 0.022) with urinary fragments of mucin-1 (standardized association size expressed in ml/min/1.73 m(2), -4.48), collagen III (-2.84), and fibrinogen (-1.70) and was bi-directionally associated (P <= 0.0006) with 2 urinary collagen I fragments (+2.28 and -3.20). The eGFR changes over 5 years (follow-up minus baseline) resulted in consistent estimates (P <= 0.025) for mucin-1 (-1.85), collagen (-1.37 to 1.43) and fibrinogen (-1.45) fragments. Relative risk of having or progressing to eGFR <60 ml/min/1.73 m(2) was associated with mucin-1. Partial least-squares analysis confirmed mucin-1 as the strongest urinary marker associated with decreased eGFR, with a score of 2.47 compared with 1.80 for a collagen I fragment as the next contender. Mucin-1 predicted eGFR decline to <60 ml/min/1.73 m(2) over and above microalbuminuria (P = 0.011) and retained borderline significance (P = 0.05) when baseline eGFR was accounted for. Discussion: In the general population, mucin-1 subunit alpha, an extracellular protein that is shed from renal tubular epithelium, is a novel biomarker associated with renal dysfunction.

OBJECTIVE: Annexin A5 (AnxA5) has been previously linked to the presence of carotid and cardiac target organ damage (TOD) in the context of heart failure and rheumatologic patients. However, information is scant in the context of hypertension. Aim of our study was to evaluate AnxA5 in treated hypertension patients compared with normotensive controls and to determine whether it is associated with vascular and heart TOD evaluated as arterial stiffness, carotid plaque and left ventricular hypertrophy. METHODS: We enrolled 123 consecutive treated hypertension and 124 normotensive controls. TOD was evaluated as pulse wave velocity (PWV, complior), left ventricular hypertrophy (echocardiography) and intima-media thickness and carotid plaque presence (ecographic methods). AnxA5 levels was dosed and compared in patients with and without hypertension and with and without TOD. RESULTS: With similar age hypertension patients showed higher SBP, DBP and AnxA5 levels (13.9¿±¿11.1 vs 10.1¿±¿8.4¿ng/ml, P¿<¿0.001) compared with controls. Regarding TOD hypertension showed higher PWV (8.5¿±¿1.8 vs 7.6¿±¿1.5¿m/s, P¿<¿0.001) and LVMI (121.7¿±¿29.3 vs 113.5¿±¿21.1¿g/m, P¿<¿0.05), whereas carotid intima-media thickness was superimposable. AnxA5 correlates with PWV (r¿=¿0.13, P¿<¿0.05) and DBP (r¿=¿0.15, P¿<¿0.01), whereas it has never been found as a significant independent predictor of TOD in linear regression analysis. CONCLUSION: Our data have shown that AnxA5 levels are increased in treated hypertension patients. In this condition, it is probably released in the plasma as a defensive mechanism through its anti-inflammatory and anticoagulants effects. We found a significant association with arterial stiffness, but AnxA5 was not found to be a significant predictor of TOD.

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.

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.

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..

Introducción y objetivos Se ha estudiado la localización anatómica, las propiedades biomecánicas y el fenotipo molecular del colágeno miocárdico tisular en 40 pacientes con estenosis aórtica grave, fracción de eyección conservada y síntomas de insuficiencia cardiaca. Métodos Se obtuvieron 2 biopsias transmurales de la pared libre del ventrículo izquierdo. La fracción del volumen de colágeno (FVC) se cuantificó mediante rojo picrosirio y la rigidez, mediante el módulo elástico de Young (YEM) evaluado con microscopia de fuerza atómica en regiones misiales y no misiales. Las FVC de tipos I y III se cuantificaron mediante microscopia confocal en áreas con determinación del YEM. Resultados Comparados con sujetos de control, la FVC misial y no misial y el cociente FVC no misial:misial (p < 0,05) estaban incrementados en los pacientes. El cociente entre la velocidad pico de la onda E mitral y la velocidad E del anillo lateral mitral de los pacientes se correlacionaba con la FVC no misial (r = 0,330; p = 0,046) y con el cociente FVC no misial:misial (r = 0,419; p = 0,012). El cociente FVCI:FVCIII y el YEM aumentaban (p ¿ 0,001) en regiones no misiales respecto de las misiales, con correlación entre ellos (r = 0,895; p < 0,001). Conclusiones En la estenosis aórtica grave con fracción de eyección conservada y síntomas de insuficiencia cardiaca, la disfunción diastólica se asocia con un depósito no misial de colágeno aumentado, predominantemente de tipo I y con mayor rigidez. Las características del colágeno tisular pueden contribuir a la disfunción diastólica en estos pacientes.

Disturbances of collagen metabolism may alter the myocardial collagen network and contribute to cardiac remodeling and prognosis in heart failure (HF). Collagen type I synthesis and degradation can be assessed indirectly by the circulating biomarkers carboxy-terminal propeptide (PICP) and carboxy-terminal telopeptide (CITP), respectively. We examined the associations between PICP and CITP and long-term mortality in patients with HF. The Optimizing Congestive Heart Failure Outpatient Clinic (OPTIMAL) project studied patients aged >= 60 years with New York Heart Association class II to IV and HF with reduced ejection fraction (EF) hospitalized with acute HF during 1996 to 1999. On entry, mean age was 75 years, blood pressure 134/80 mm Hg, EF 34%, brain natriuretic peptide 312 pg/ml; 55% had atrial fibrillation. Dates of mortality were collected from administrative databases and medical records up until 2008. Follow-up was 9 to 13 years in all 132 patients, and mean survival was 5.5 +/- 4.0 years. Baseline PICP tended to be higher, CITP was higher, and the PICP:CITP ratio was lower in the 102 deceased, compared with the 30 patients alive. Multivariable Cox regression analyses including 2 established risk factor models performed for all-cause (n = 101) and cardiovascular mortality (n = 61) show PICP and CITP to be independent predictors for all-cause and cardiovascular mortality. In,conclusion, disturbances of collagen type I metabolism have independent prognostic implications for long-term all-cause and cardiovascular mortality in patients with HF with reduced EF. The results suggest excessive degradation to be the predominant disturbance associated with untoward prognosis and adds information on possible target mechanisms for future therapy. (C) 2017 Elsevier Inc. All rights reserved.

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

Current knowledge on the pathogenesis of diastolic heart failure predominantly rests on case-control studies involving symptomatic patients with preserved ejection fraction and relying on invasive diagnostic procedures including endomyocardial biopsy. Our objective was to gain insight in serum and urinary biomarkers reflecting collagen turnover and associated with asymptomatic diastolic LV dysfunction. We randomly recruited 782 Flemish (51.3% women; 50.5 years). We assessed diastolic LV function from the early and late diastolic peak velocities of the transmitral blood flow and of the mitral annulus. By sequencing urinary peptides, we identified 70 urinary collagen fragments. In serum, we measured carboxyterminal propeptide of procollagen type 1 (PICP) as marker of collagen I synthesis and tissue inhibitor of matrix metalloproteinase type 1 (TIMP-1), an inhibitor of collagen-degrading enzymes. In multivariable-adjusted analyses with Bonferroni correction, we expressed effect sizes per 1-SD in urinary collagen I (uCI) or collagen III (uCIII) fragments. In relation to uCI fragments, e' decreased by 0.183 cm/s (95% confidence interval, 0.017 to 0.350; p = 0.025), whereas E/e' increased by 0.210 (0.067 to 0.353; p = 0.0012). E/e' decreased with uCIII by 0.168 (0.021 to 0.316; p = 0.018). Based on age-specific echocardiographic criteria, 182 participants (23.3%) had subclinical diastolic LV dysfunction. Partial least squares discriminant analysis contrasting normal vs. diastolic LV dysfunction confirmed the aforementioned associations with the uCI and uCIII fragments. PICP and TIMP-1 increased in relation to uCI (p<0.0001), whereas these serum markers decreased with uCIII (p <= 0.0006). Diastolic LV dysfunction was associated with higher levels of TIMP-1 (653 vs. 696 ng/mL; p = 0.013). In a general population, the non-invasively assessed diastolic LV function correlated inversely with uCI and serum markers of collagen I deposition, but positively with uCIII. These observations generalise previous studies in patients to randomly recruited people, in whom diastolic LV function ranged from normal to subclinical impairment, but did not encompass overt diastolic heart failure.

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.

MicroRNAs have been associated with cardiomyocyte apoptosis, a process involved in myocardial remodelling in aortic valve (Av) stenosis (AS). Our aim was to analyse whether the dysregulation of myocardial microRNAs was related to cardiomyocyte apoptosis in AS patients. Endomyocardial biopsies were obtained from 28 patients with severe AS (based on pressure gradients and Av area) referred for Av replacement and from necropsies of 10 cardiovascular disease-free control subjects. AS patients showed an increased (P<0.001) cardiomyocyte apoptotic index (CMAI) compared with controls. Two clusters of patients were identified according to the CMAI: group 1 (CMAI ¿ 0.08%; n=16) and group 2 (CMAI > 0.08%; n=12). Group 2 patients presented lower cardiomyocyte density (P<0.001) and ejection fraction (P<0.05), and higher troponin T levels (P<0.05), prevalence of heart failure (HF; P<0.05) and NT-proBNP levels (P<0.05) than those from group 1. miRNA expression profile analysed in 5 patients randomly selected from each group showed 64 microRNAs down-regulated and 6 up-regulated (P<0.05) in group 2 compared with group 1. Those microRNAs with the highest fold-change were validated in the full two groups corroborating that miR-10b, miR-125b-2* and miR-338-3p were down-regulated (P<0.05) in group 2 compared with group 1 and control subjects. These three microRNAs were inversely correlated (P<0.05) with the CMAI. Inhibition of miR-10b induced an increase (P<0.05) of apoptosis and increased expression (P<0.05) of apoptosis protease-activating factor-1 (Apaf-1) in HL-1 cardiomyocytes. In conclusion, myocardial down-regulation of miR-10b may be involved in increased cardiomyocyte apoptosis in AS patients, probably through Apaf-1 up-regulation, contributing to cardiomyocyte damage and to the development of HF.

Oxidative stress (OS) contributes to cardiovascular damage in type 2 diabetes mellitus (T2DM). The peptide glucagon-like peptide-1 (GLP-1) inhibits OS and exerts cardiovascular protective actions. Our aim was to investigate whether cardiac remodeling (CR) and cardiovascular events (CVE) are associated with circulating GLP-1 and biomarkers of OS in T2DM patients. We also studied GLP-1 antioxidant effects in a model of cardiomyocyte lipotoxicity. We examined 72 T2DM patients with no coronary or valve heart disease and 14 nondiabetic subjects. A median of 6 years follow-up information was obtained in 60 patients. Circulating GLP-1, dipeptidyl peptidase-4 activity, and biomarkers of OS were quantified. In T2DM patients, circulating GLP-1 decreased and OS biomarkers increased, compared with nondiabetics. Plasma GLP-1 was inversely correlated with serum 3-nitrotyrosine in T2DM patients. Patients showing high circulating 3-nitrotyrosine and low GLP-1 levels exhibited CR and higher risk for CVE, compared to the remaining patients. In palmitate-stimulated HL-1 cardiomyocytes, GLP-1 reduced cytosolic and mitochondrial oxidative stress, increased mitochondrial ATP synthase expression, partially restored mitochondrial membrane permeability and cytochrome c oxidase activity, blunted leakage of creatine to the extracellular medium, and inhibited oxidative damage in total and mitochondrial DNA. These results suggest that T2DM patients with reduced circulating GLP-1 and exacerbated OS may exhibit CR and be at higher risk for CVE. In addition, GLP-1 exerts antioxidant effects in HL-1 palmitate-overloaded cardiomyocytes. It is proposed that therapies aimed to increase GLP-1 may counteract OS, protect from CR, and prevent CVE in patients with T2DM.

BACKGROUND/OBJECTIVES: The validation of effective screening tools for the identification of patients with subclinical myocardial remodelling is a major clinical need. Thus, we explored the associations of circulating biomarkers of cardiomyocyte injury and stress with subclinical cardiac remodelling and dysfunction, and with biomarkers reflecting collagen turnover. METHODS: We randomly recruited 727 subjects from a general population (51.2% women; mean age 51.3 years). Measurements included echocardiographic left atrial (LA) and left ventricular (LV) structure and function, quantification of high sensitivity cardiac Troponin T (hs-cTnT), NT-proBNP, and biomarkers of collagen types I and III turnover. RESULTS: In unadjusted and adjusted analyses, the prevalence of LA enlargement (LAE), LV hypertrophy (LVH) and LV diastolic dysfunction (LVDD) increased with higher hs-cTnT (P ¿ 0.031). NT-proBNP was independently associated with LVDD (P=0.009). Both biomarkers combined yielded significant integrated discrimination and net reclassification improvements (P ¿ 0.014 and P ¿ 0.009, respectively) for LAE, LVH and LVDD, over the conventional risk factors, and were independently and positively associated with biomarkers of collagen type I turnover. In a sensitivity analysis, after excluding participants with previous cardiac diseases, our findings remained consistent. CONCLUSIONS: Our population-based study suggested that subclinical LV and LA remodelling were associated with hs-cTnT, and that, in combination with NT-proBNP, hs-cTnT showed incremental diagnostic utility over the conventional risk factors. Both biomarkers were associated with biomarkers of collagen type I turnover. Thus, biomarkers of cardiomyocyte microinjury and hemodynamic stress may stimulate fibrosis-related mechanisms and facilitate the diagnosis of subclinical LA and LV remodelling and dysfunction in the general population.

Objectives: Cardiotrophin-1 (CT-1) induces hypertrophic growth and contractile dysfunction in cardiomyocytes. This cross-sectional study was aimed to analyze CT-1 associations with echocardiographically assessed left ventricular systolic properties taking into account the influence of left ventricular growth [i.e. left ventricular hypertrophy (LVH) and inappropriate left ventricular mass (iLVM)] in asymptomatic hypertensive patients. Methods: Serum CT-1 was measured by ELISA in 278 asymptomatic hypertensive patients with a left ventricular ejection fraction more than 50% and in 25 age and sex-matched normotensive patients. Results: Serum CT-1 was increased in hypertensive patients as compared to normotensive patients. CT-1 was directly correlated with parameters of left ventricular mass (LVM) and inversely correlated with parameters assessing myocardial systolic function and left ventricular chamber contractility in hypertensive patients, these associations being independent of a number of potential confounding factors. Interestingly, the associations of CT-1 with myocardial systolic function were independent of LVM even in patients with LVH or iLVM. In addition, there was a significant increment of serum CT-1 in hypertensive patients with LVH or iLVM, especially in those in whom LVH or iLVM were accompanied by impaired myocardial systolic function, as compared to the remaining hypertensive patients and normotensive patients. Plasma amino-terminal pro-brain natriuretic peptide was not correlated with any of the assessed left ventricular systolic parameters in either group of patients. Conclusion: These findings suggest that serum CT-1 is associated with myocardial systolic dysfunction in asymptomatic hypertensive patients, independently of LVM, even in those patients with pathologic left ventricular growth.

We investigated whether the pro-fibrotic matricellular protein osteopontin (OPN) is associated with the enzymes involved in the extracellular synthesis of fibril-forming collagen type I (i.e. procollagen C-proteinase, PCP) and its cross-linking to form insoluble fibrils (i.e. lysyl oxidase, LOX) in heart failure (HF) of hypertensive origin. OPN, PCP, and LOX were assessed by histochemical and molecular methods in the myocardium of 21 patients with hypertensive heart disease (HHD) and HF. Whereas the myocardial expression of OPN was very scarce in control hearts (n 10), it was highly expressed in HF patients (P 0.0001). OPN was directly correlated with LOX (r 0.460, P 0.041), insoluble collagen (r 0.534, P 0.015), pulmonary capillary wedge pressure (r 0.558; P 0.009), and left-ventricular (LV) chamber stiffness (r 0.458, P 0.037), and inversely correlated with LV ejection fraction (r 0.513, P 0.017) in all patients. OPN did not correlate with PCP and other parameters assessing collagen synthesis by fibroblasts or degradation by matrix metalloproteinases. In vitro studies showed that OPN significantly (P 0.05) increases the expression and activity of LOX in human cardiac and dermal fibroblasts. An excess of OPN is associated with increased LOX and insoluble collagen, as well as with LV stiffness and systolic dysfunction in patients with HHD and HF. In addition, OPN up-regulates LOX in human fibroblasts. It is suggested that the OPNLOX axis might facilitate the formation of insoluble collagen (i.e. stiff and resistant to degradation) and the subsequent alteration in LV mechanical properties and function in patients with HHD and HF.

Background: Patients with type 2 diabetes mellitus (T2DM) present subclinical left ventricular systolic and/or diastolic dysfunction (LVD). Dipeptidyl peptidase-4 (DPP4) inactivates peptides that possess cardioprotective actions. Our aim was to analyze whether the activity of circulating DPP4 is associated with echocardiographically defined LVD in asymptomatic patients with T2DM. Methods: In this cross-sectional study, we examined 83 T2DM patients with no coronary or valve heart disease and 59 age and gender-matched non-diabetic subjects. Plasma DPP4 activity (DPP4a) was measured by enzymatic assay and serum amino-terminal pro-brain natriuretic peptide (NT-proBNP) was measured by enzyme-linked immunosorbent assay. LV function was assessed by two-dimensional echocardiographic imaging, targeted M-mode recordings and Doppler ultrasound measurements. Differences in means were assessed by t-tests and one-way ANOVA. Associations were assessed by adjusted multiple linear regression and logistic regression analyses. Results: DPP4a was increased in T2DM patients as compared with non-diabetic subjects (5855 +/- 1632 vs 5208 +/- 957 pmol/min/mL, p < 0.05). Clinical characteristics and echocardiographic parameters assessing LV morphology were similar across DPP4a tertiles in T2DM patients. However, prevalence of LVD progressively increased across incremental DPP4a tertiles (13%, 39% and 71%, all p < 0.001). Multivariate regression analysis confirmed the independent associations of DPP4a with LVD in T2DM patients (p < 0.05). Similarly, multiple logistic regression analysis showed that an increase of 100 pmol/min/min plasma DPP4a was independently associated with an increased frequency of LVD with an adjusted odds ratio of 1.10 (95% CI, 1.04 to 1.15, p = 0.001). Conclusions: An excessive activity of circulating DPP4 is independently associated with subclinical LVD in T2DM patients. Albeit descriptive, these findings suggest that DPP4 may be involved in the mechanisms of LVD in T2DM.

Activation of apoptosis contributes to cardiomyocyte dysfunction and death in diabetic cardiomyopathy. The peptide glucagon-like peptide-1 (GLP-1), a hormone that is the basis of emerging therapy for type 2 diabetic patients, has cytoprotective actions in different cellular models. We investigated whether GLP-1 inhibits apoptosis in HL-1 cardiomyocytes stimulated with staurosporine, palmitate, and ceramide. Studies were performed in HL-1 cardiomyocytes. Apoptosis was induced by incubating HL-1 cells with staurosporine (175 nM), palmitate (135 ¿M), or ceramide (15 ¿M) for 24 h. In staurosporine-stimulated HL-1 cardiomyocytes, phosphatidylserine exposure, Bax-to-Bcl-2 ratio, Bad phosphorylation (Ser(136)), BNIP3 expression, mitochondrial membrane depolarization, cytochrome c release, caspase-3 activation, DNA fragmentation, and mammalian target of rapamycin (mTOR)/p70S6K phosphorylation (Ser(2448) and Thr(389), respectively) were assessed. Apoptotic hallmarks were also measured in the absence or presence of low (5 mM) and high (10 mM) concentrations of glucose. In addition, phosphatidylserine exposure and DNA fragmentation were analyzed in palmitate- and ceramide-stimulated cells. Staurosporine increased apoptosis in HL-1 cardiomyocytes. GLP-1 (100 nM) partially inhibited staurosporine-induced mitochondrial membrane depolarization and completely blocked the rest of the staurosporine-induced apoptotic changes. This cytoprotective effect was mainly mediated by phosphatidylinositol 3-kinase (PI3K) and partially dependent on ERK1/2. Increasing concentrations of glucose did not influence GLP-1-induced protection against staurosporine. Furthermore, GLP-1 inhibited palmitate- and ceramide-induced phosphatidylserine exposure and DNA fragmentation. Incretin GLP-1 protects HL-1 cardiomyocytes against activation of apoptosis. This cytoprotective ability is mediated mainly by the PI3K pathway and partially by the ERK1/2 pathway and seems to be glucose independent. It is proposed that therapies based on GLP-1 may contribute to prevent cardiomyocyte apoptosis.