Objective: To present a novel method that uses an epigenetic fingerprint to measure changes in plasma concentrations of cardiac-specific cell-free DNA (CS-cfDNA) as a marker of myocardial cell death.
Methods: This prospective, analytic, observational comparative study included patients with heart disease or multiple risk factors for heart disease undergoing major noncardiac, mostly vascular surgery, requiring an arterial-line, and at least 24 h hospitalization in the post anaesthesia care unit or critical care unit after surgery. Blood samples were collected at least four times per patient to measure troponin-T (via high-sensitivity troponin-T test) and CS-cfDNA pre- and postoperatively.
B-cell lymphoma 2-associated athanogene-3 (Bag3) is expressed in all animal species, with Bag3 levels being most prominent in the heart, the skeletal muscle, the central nervous system, and in many cancers. Preclinical studies of Bag3 biology have focused on animals that have developed compromised cardiac function; however, the present studies were performed to identify the pathways perturbed in the heart even before the occurrence of clinical signs of dilatation and failure of the heart. These studies show that hearts carrying variants that knockout one allele of have significant alterations in multiple cellular pathways including apoptosis, autophagy, mitochondrial homeostasis, and the inflammasome.
View Article and Find Full Text PDFBackground: Vascular endothelial cells (VECs) are an essential component of each tissue, contribute to multiple pathologies, and are targeted by important drugs. Yet, there is a shortage of biomarkers to assess VEC turnover.
Methods: To develop DNA methylation-based liquid biopsies for VECs, we determined the methylome of VECs isolated from freshly dissociated human tissues.
BAG3 is a 575 amino acid protein that is found throughout the animal kingdom and homologs have been identified in plants. The protein is expressed ubiquitously but is most prominent in cardiac muscle, skeletal muscle, the brain and in many cancers. We describe BAG3 as a quintessential multi-functional protein.
View Article and Find Full Text PDFNitric oxide (NO) and -nitrosothiol (SNO) are considered cardio- and vasoprotective substances. We now understand that one mechanism in which NO/SNOs provide cardiovascular protection is through their direct inhibition of cardiac G protein-coupled receptor (GPCR) kinase 2 (GRK2) activity via -nitrosylation of GRK2 at cysteine 340 (C340). This maintains GPCR homeostasis, including β-adrenergic receptors, through curbing receptor GRK2-mediated desensitization.
View Article and Find Full Text PDFHigh-fat diet (HFD)-induced obesity is associated with accumulation of inflammatory cells predominantly in visceral adipose depots [visceral adipose tissue (VAT)] rather than in subcutaneous ones [subcutaneous adipose tissue (SAT)]. The cellular and molecular mechanisms responsible for this phenotypic difference remain poorly understood. Controversy also exists on the overall impact that adipose tissue inflammation has on metabolic health in diet-induced obesity.
View Article and Find Full Text PDFWe present a patient who was admitted for carotid endarterectomy due to tight carotid stenosis and recent amaurosis fugax. His medical history included significant coronary artery disease with stable angina pectoris, hypertension with wide pulse pressure, chronic renal failure, and anemia. During preparation for surgery, the patient developed type 2 myocardial infarction with prolonged chest pain, ST depressions on electrocardiogram, and significant troponin elevations.
View Article and Find Full Text PDFMethylation patterns of circulating cell-free DNA (cfDNA) contain rich information about recent cell death events in the body. Here, we present an approach for unbiased determination of the tissue origins of cfDNA, using a reference methylation atlas of 25 human tissues and cell types. The method is validated using in silico simulations as well as in vitro mixes of DNA from different tissue sources at known proportions.
View Article and Find Full Text PDFLiver damage is typically inferred from serum measurements of cytoplasmic liver enzymes. DNA molecules released from dying hepatocytes are an alternative biomarker, unexplored so far, potentially allowing for quantitative assessment of liver cell death. Here we describe a method for detecting acute hepatocyte death, based on quantification of circulating, cell-free DNA (cfDNA) fragments carrying hepatocyte-specific methylation patterns.
View Article and Find Full Text PDFDetection of cardiomyocyte death is crucial for the diagnosis and treatment of heart disease. Here we use comparative methylome analysis to identify genomic loci that are unmethylated specifically in cardiomyocytes, and develop these as biomarkers to quantify cardiomyocyte DNA in circulating cell-free DNA (cfDNA) derived from dying cells. Plasma of healthy individuals contains essentially no cardiomyocyte cfDNA, consistent with minimal cardiac turnover.
View Article and Find Full Text PDFMPO (myeloperoxidase) is a peroxidase enzyme secreted by activated leukocytes that plays a pathogenic role in cardiovascular disease, mainly by initiating endothelial dysfunction. The molecular mechanisms of the endothelial damaging action of MPO remain though largely elusive. Calpain is a calcium-dependent protease expressed in the vascular wall.
View Article and Find Full Text PDFObjective: Mice with global null mutation of Ceacam1 (Cc1), display impairment of insulin clearance that causes hyperinsulinemia followed by insulin resistance, elevated hepatic de novo lipogenesis, and visceral obesity. In addition, they manifest abnormal vascular permeability and elevated blood pressure. Liver-specific rescuing of Ceacam1 reversed all of the metabolic abnormalities in Cc1 mice.
View Article and Find Full Text PDFBackground: Myocardial dysfunction may contribute to circulatory failure in sepsis. There is growing evidence of an association between left ventricular diastolic dysfunction (LVDD) and mortality in septic patients. Utilizing echocardiography, we know that tissue Doppler imaging (TDI) variables e' and E/e' are reliable predictors of LVDD and are useful measurements to estimate left ventricular (LV) filling pressures.
View Article and Find Full Text PDFGenetic variants at the solute carrier family 39 member 8 (SLC39A8) gene locus are associated with the regulation of whole-blood manganese (Mn) and multiple physiological traits. SLC39A8 encodes ZIP8, a divalent metal ion transporter best known for zinc transport. Here, we hypothesized that ZIP8 regulates Mn homeostasis and Mn-dependent enzymes to influence metabolism.
View Article and Find Full Text PDFBackground: Myocardial dysfunction may contribute to the haemodynamic instability which accompanies sepsis, and may result in circulatory failure. There is no association between systolic dysfunction (SD) and mortality in septic patients and there is conflicting evidence regarding the effects of diastolic dysfunction (DD) on mortality in septic patients.
Methods: We conducted a systematic review and meta-analysis to investigate DD and mortality in septic patients.
Background: In vitro studies suggested that circulating inflammatory cytokines cause septic myocardial dysfunction. However, no in vivo clinical study has investigated whether serum inflammatory cytokine concentrations correlate with septic myocardial dysfunction.
Methods: Repeated echocardiograms and concurrent serum inflammatory cytokines (IL-1β, IL-6, IL-8, IL-10, IL-18, tumor necrosis factor-α, and monocyte chemoattractant protein-1) and cardiac biomarkers (high-sensitivity [hs] troponin-T and N-terminal pro-B-type natriuretic peptide [NT-proBNP]) were examined in 105 patients with severe sepsis and septic shock.
Objective: Serum troponin concentrations predict mortality in almost every clinical setting they have been examined, including sepsis. However, the causes for troponin elevations in sepsis are poorly understood. We hypothesized that detailed investigation of myocardial dysfunction by echocardiography can provide insight into the possible causes of troponin elevation and its association with mortality in sepsis.
View Article and Find Full Text PDFRationale: Human genetics have implicated the 5-lipoxygenase enzyme in the pathogenesis of cardiovascular disease, and an inhibitor of the 5-lipoxygenase activating protein (FLAP) is in clinical development for asthma.
Objective: Here we determined whether FLAP deletion modifies the response to vascular injury.
Methods And Results: Vascular remodeling was characterized 4 weeks after femoral arterial injury in FLAP knockout mice and wild-type controls.