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Background and Aims: Dapagliflozin, a sodium-glucose co-transporter 2 inhibitor, improves glucose uptake by epicardial adipose tissue (EAT). However, its metabolism might raise the lactate production and acidosis under hypoxia conditions, i.e. coronary artery disease (CAD), or lipogenesis and, in consequence, expand adipose tissue. Since lactate secreted by adipose tissue is correlated with tissue stress and inflammation, our aim was to study glucose metabolism by epicardial fat in CAD and its regulation by dapagliflozin., Methods: Paired EAT and subcutaneous adipose tissue (SAT) biopsies from 49 patients who underwent open-heart surgery were cultured and split into three equal pieces, some treated with and others without dapagliflozin at 10 or 100 μM for 6 h. Anaerobic glucose metabolites were measured in supernatants of fat pads, and acidosis on adipogenesis-induced primary culture cells was analysed by colorimetric or fluorescence assays. Gene expression levels were assessed by real-time polymerase chain reaction., Results: Our results showed that dapagliflozin reduced the released lactate and acidosis in epicardial fat (p < 0.05) without changes in lipid storage-involved genes. In addition, this drug induced gene expression levels of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α), a mitochondrial biogenesis-involved gene in both EAT and SAT (p < 0.05). After splitting the population regarding the presence of CAD, we observed higher lactate production in EAT from these patients (2.46 [1.75-3.47] mM), which was reduced after treatment with dapagliflozin 100 μM (1.99 [1.08-2.99] mM, p < 0.01)., Conclusions: Dapagliflozin improved glucose metabolism without lipogenesis-involved gene regulation or lactate production, mainly in patients with CAD. These results suggest an improvement of glucose oxidation metabolism that can contribute to cardiovascular benefits., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Imaging techniques have shown the association between left atrial adipose tissue (LAAT) volume and atrial fibrillation (AF) risk., Purpose: To analyze 1) adipokines in peripheral and atrial plasma from patients undergoing AF ablation; 2) its association with LAAT volume measured by multislice CT and 3) its predictive value for AF recurrence., Methods: Seventy consecutive patients undergoing AF catheter ablation were screened. Blood samples were extracted from the left atrium and peripheral vein before catheter ablation. Multiplex fluorimetric immunoassay, enzyme-linked immunoassay and Western blot techniques were used for analyzing some adipokines, fatty acid binding protein 4 (FABP4), and leptin and perilipin analysis, respectively. Patients were followed up with clinical visits until one year after ablation. Generalized additive regression (GAM) was used for determining the best indicator of LAAT volume. Logistic regression analysis determined the best predictor of AF recurrence after persistent AF catheter ablation., Results: Our results showed 1) differences in the levels of FABP4 between peripheral and left atrial blood samples. 2) persistent AF patients had higher LAAT volume than those with paroxysmal AF (5.12 ± 2.76 vs. 3.82 ± 1.81 mL; p < 0.036). FABP4 was the best adipokine associated with LAAT in persistent AF (p < 0.01) 3) and predictive value for AF recurrence after catheter ablation (AUC-ROC 0.883 with 95% CI 0.739-1.028)., Conclusions: Plasma FABP4 levels, which were associated with LAAT volume in persistent AF, can be predictors of recurrence after catheter ablation. Whether persistent AF patients require more intensive management and monitoring according to FABP4 deserves further investigation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Inflammation and nutritional state are involved in the pathogenesis of heart failure (HF)., Objective: To study the contribution of alpha-1-acid-glycoprotein (AGP) to these factors and its prognostic value in acute (AHF) or chronic HF (CHF)., Methods: The observational study has included 147 patients (mean age 70years, 62% men) admitted to a cardiology department for HF and followed-up for an average 326.6±140.8days. Blood AGP values were measured by Enzyme-Linked ImmunoSorbent Assay. Monocytes subsets were determined with CD14 and CD16 antibodies by flow cytometry and body composition was measured by dual-energy X-ray absorptiometry. The regulation of tumor necrosis factor (TNF-α) and leptin by AGP in epicardial adipose tissue (EAT) were analyzed by real time polymerase chain reaction., Results: High AGP, that was associated with CD14 + CD16 + monocytes, and proBNP levels at the discharge were indicators of rehospitalization for HF in AHF patients. However, low AGP levels determined a worse nutritional state in CHF patients. The leptin levels were downregulated by high AGP concentration in epicardial fat., Conclusion: AGP is a dual indicator in HF because high levels are predictors of adverse outcomes in AHF but low levels are related to the worse nutritional status in CHF. The regulation of leptin by AGP in epicardial fat might suggest a new pathway as protective mechanism in CHF., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objective: Type 2 diabetes mellitus (T2DM) is associated with fat and autonomic system dysfunction. Epicardial adipose tissue (EAT) plays an endocrine role over the heart. Since orosomucoid (ORM) has local actions around the coronaries, our aim was to assess the relationship between its secretion profile by EAT and its catecholaminergic regulation in patients with T2DM and coronary artery disease (CAD)., Methods: We obtained EAT, subcutaneous adipose tissue (SAT) and plasma from 55 patients undergoing cardiac surgery. Fat explants were stimulated with isoproterenol (ISO) 1 μM for 6 h. After, the fat explants released-ORM and plasma levels were analyzed by ELISA. mRNA or protein expression was analyzed by real time PCR or western blot, respectively. The effects of ORM on endothelial cells were analyzed by impedance and wound healing assays., Results: We observed that EAT-released ORM levels were higher than SAT (328 ± 185 vs 58 ± 45 ng/mL; p < 0.001). Interestingly, EAT secretion was lower in patients with than those without T2DM (260 ± 141 vs 370 ± 194 ng/mL; p < 0.05) and this difference was enhanced after ISO stimulation (p < 0.01). However, plasma levels (412 ± 119 vs 594 ± 207 μg/mL) and EAT-released ORM levels were higher in patients with than those without CAD (384 ± 195 vs 279 ± 159 ng/mL; p < 0.05). ISO stimulation, also reduced the EAT released-ORM levels in patients with CAD. On human endothelial cells, ORM induced an increase of healing and proliferation in a dose-dependent manner., Conclusion: EAT-released ORM levels in patients with T2DM or CAD and its regulation by catecholamines might be the mirror of local endothelium dysfunction or inflammatory process in different cardiovascular disorders., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Aims: S100A9 is a new inflammatory marker associated with obesity and cardiovascular disease. Because epicardial adipose tissue (EAT) is an inflammatory source in coronary artery disease (CAD), our aim was to evaluate the S100A9 levels in plasma and EAT and its association with CAD., Main Methods: Blood, EAT and/or subcutaneous adipose tissue (SAT) biopsies were obtained from 89 patients undergoing elective cardiac surgery. Plasma S100A9 and adiponectin were analyzed by enzyme-linked immunosorbent assay (ELISA) and mRNA expression in both fat pads and were measured by real-time polymerase chain reaction (PCR)., Key Findings: Our results have shown higher levels of plasma S100A9 in patients with CAD than those without (29 [10-50] vs. 17 [3-28] ng/mL; p=0.007). They were dependent on the number of injured-coronaries (p=0.002) with tendency toward negative association with plasma adiponectin (p=0.139). Although EAT expressed higher levels than SAT and their levels were higher in CAD patients, this last difference did not reach statistical significance. However, there was a positive correlation between neutrophils and EAT S100A9 expression (p=0.007) that may reveal an increase of neutrophil filtration on this fat pad., Significance: Plasma S100A9 levels are increased in chronic CAD. The absence of differences regarding EAT S100A9 expression levels indicates a differential inflammatory process between fat tissues and blood in CAD process., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: Recent studies have focused on the potential role of epicardial adipose tissue (EAT) in the physiopathology of several metabolic and cardiovascular diseases, especially coronary artery disease (CAD). We aimed to study whether there are differences in the proteome and the secretome between epicardial and subcutaneous adipose tissue (SAT) from patients with and without CAD., Methods: EAT and SAT samples were collected from 64 patients undergoing elective cardiac surgery either for coronary artery bypass grafting or valve surgery. One or two-dimensional electrophoresis were performed on tissue samples and media collected at 3, 6, 24 or 48 of tissue culture. Protein identification was performed with mass spectrometry, and the results were then validated with Western blot or enzyme immunoassay. mRNA expression levels were analysed by real time polymerase chain reaction., Results: The release of several proteins was found to be higher in EAT that in SAT. Remarkably, there were higher levels of apolipoprotein A-I and glutation S-transferase P release, whereas mRNA expression of fatty acid binding protein 4 was lower in EAT. Although apolipoprotein A-I protein quantity in EAT was similar between CAD and non CAD patients, its released levels from this fat pad were lower in CAD., Conclusion: EAT and SAT show different profiles of protein release and a different pattern was also found in samples from patients with CAD. These findings might support the hypothesis that EAT plays an interesting role in the physiopathology of atherosclerosis and CAD., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia found in clinical practice. We combined high-resolution two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) to compare the atrial proteome of subjects with AF versus controls with sinus rhythm (SR). Our aim was to identify novel differentially regulated proteins that could be related to the development of the arrhythmia., Methods: Human atrial appendage tissue samples from patients undergoing heart surgery with AF or SR were analyzed by high-resolution 2-DE. Proteins of interest were identified by MS and validated by western blotting and inmunohistochemistry., Results: Our analysis allowed the detection of over 2300 protein spots per gel. Following differential image analysis, we found 22 spot differences between the AF and SR groups in the 4-7 isoelectric point range, leading to the identification of 15 differentially regulated proteins. The main group of proteins identified was that of heat shock proteins (HSPs), including TRAP-1, HspB3, HspΒ6 and AHA1. Some of the differences detected between AF and SR for the above proteins were due to post-translational modifications. In addition, we identified the structural protein fibulin-1 as down-regulated in atrial tissue from AF patients., Conclusions: High-resolution 2-DE analysis of human atrial tissue revealed that AF is associated with changes in structural proteins and an important number of HSPs. The lower expression of the structural protein fibulin-1 in atrial tissue from AF patients might reflect the myocardial structural changes that take place in the arrhythmia., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Leptin is a pleiotropic hormone that regulates body weight and energy expenditure. Recent findings suggest that leptin may be involved in acute and/or chronic inflammation, however only limited results are available describing the effects of in vivo models of acute inflammation on leptin secretion. The aim of this study was to evaluate serum leptin levels in response to two well-established models of acute inflammation in rats: carrageenan rat paw induced oedema and carrageenan induced pleurisy. Our results clearly show that leptin levels rise in rats in which both oedema and pleurisy were induced. Serum leptin levels in carrageenan induced paw oedema were 3.86+/-0.16 microg/L in comparison to 1.83+/-0.17 microg/L of control animals (p<0.001). A similar result was observed in carrageenan induced pleurisy animals in which leptin levels were 4.87+/-0.27 microg/L in comparison to 2.19+/-0.16 microg/L of control animals (p<0.001). The increase in leptin levels induced following carrageenan-induced pleurisy appears to be dependent on adrenal function and it is markedly blunted in adrenalectomized rats. Leptin levels in carrageenan induced pleurisy, carried out on adrenalectomized rats, were lower than intact inflamed animals, suggesting a possible involvement of endogenous glucocorticoids. In summary the results here presented show that: a) an elevated plasma leptin concentration was induced during experimental models of inflammation b) this increase is mediated to a large extent by glucocorticoids. In conclusion, acute experimental models of inflammation are associated with changes in circulating leptin suggesting a possible involvement of this hormone in the anorexia/cachexia that is frequently associated with inflammatory processes. Furthermore, our data indicate the existence of a feedback loop among glucocorticoids and leptin which might contribute to the immune response to lace the inflammatory process.

An alternative procedure for the determination of Mo(VI) with thiocyanate is proposed. According to this procedure, Mo(VI) is extracted with alpha-benzoinoxime by single-phase extraction in a water/ethanol/chloroform homogeneous ternary solvent system at a nominal pH of 2 and then is spectrophotometrically determined, after separation from the matrix in a similar solvent mixture. The determination is performed by forming a homogeneous phase using the solvent containing the extracted metal as one of the components of the reactional solvent system, eliminating the time-consuming metal complex destruction step. Under these experimental conditions, the calibration graph is linear up to 8.00 mug ml(-1), according to the equation A=0.005+0.143C(Mo(VI)) (r(2)=0.9999). Using the experimental conditions described, the absorbance readings are stable for periods up to 18 h. The interference of the most common interfering species for this method can be prevented by adding Fe(2+) and H(2)PO(4)(-) to the solvent system prior to the extraction step. The accuracy of the proposed method was evaluated by comparing with standard samples determined by atomic absorption measurements with background correction.