Systematic Brain Natriuretic Peptide Measurement for Cardiac Screening in Patients with Severe Obesity: The OLECOEUR Study.

INTRODUCTION: Heart failure (HF) is difficult to diagnose in obese patients because of cardiovascular and pulmonary comorbidities associated with physical deconditioning, all of which lead to dyspnea. METHODS: The OLECOEUR study is a prospective screening for HF using systematic brain natriuretic peptide (BNP) measurement in ambulatory patients with obesity from a department of Nutrition (Paris, France). Clinical, biological, and echocardiographic data were extracted from electronic medical records. RESULTS: We included 1,506 patients middle-aged (mean age: 47.2 ± 14.6 years old) with severe obesity (mean body mass index: 40.4 ± 6.6 kg/m2). Patients with BNP ≥35 pg/mL had left heart remodeling including thicker interventricular septum (10.4 ± 2.0 vs. 9.6 ± 1.8 mm; p = 0.0008), higher left ventricular mass (89.9 ± 24.3 vs. 77.2 ± 20.0 g/m2; p = 0.0009), and significant changes in both left and right atria consistent with a higher proportion of prior atrial fibrillation. Markers of right heart remodeling on echocardiography were also significantly higher (pulmonary artery systolic pressure: 33.3 ± 17.3 vs. 24.5 ± 6.3 mm Hg; p = 0.0002). CONCLUSION: The OLECOEUR study shows left and right subclinical cardiac remodeling in obese patients screened for HF with systematic dosing of BNP with usual cut-off of 35 pg/mL.

H3K27me3 at pericentromeric heterochromatin is a defining feature of the early mouse blastocyst.

Early mouse development is characterized by structural and epigenetic changes while cells progress towards differentiation. At blastocyst stage, the segregation of the three primordial lineages is accompanied by establishment of differential patterns of DNA methylation and post-translational modifications of histones, such as H3K27me3. Here, we analysed the dynamics of H3K27me3 at pericentromeric heterochromatin (PCH) during early development. We also followed the localization of EZH2 and BEND3, previously shown in ESCs to drive PRC2 to hypomethylated PCH. We show that the location of H3K27me3 at PCH, in addition to H3K9me3, is a defining feature of embryonic cells in vivo. Moreover, it may play an important role in structuring PCH and preserving genomic integrity at a time of globally relaxed chromatin. At peri-implantation stages, while DNA methylation is still low, EZH2 and then H3K27me3, leave PCH in epiblast progenitors at the time of their spatial segregation from primitive endoderm cells, while BEND3 remains there up to implantation. The comparison with stem cells (ESCs and TSCs) reveals that the epigenetic marks (i.e. H3K9me3 and H3K27me3) of PCH are reset during in vitro derivation and only partially restored thereafter. This highlights possible divergences between in vitro and "in embryo" epigenetic regulation regarding constitutive heterochromatin.