Genesis of epicardial adipocytes and its association with progenitor markers, muscarinic receptor type 3 and b-blockers intake in patients with cardiovascular disease

Introduction

Epicardial fat thickness or volume was found to be associated with cardiovascular disease (CVD). Our aim was to study the epicardial adipocyte-progenitors' markers and its association with cholinergic or adrenergic activity in patients with cardiovascular disease.

Materials and methods

We have included epicardial adipose tissue (EAT) biopsies from 29 patients underwent open-heart surgery. From 10 patients (69±5 years old, 31±8 kg/ m2, 40% CAD, 40% HF, 60% AF, 0% T2DM) stromal cells from epicardial and subcutaneous fat were isolated after collagenase activity and cultured for 14 days and then submitted to adipogenesis for next 14 days. Samples from 19 patients (60±9 years old, 29±4 kg/m2, 42% CAD, 37% HF, 32% AF, 32% T2DM, 53% β-blockers) were used for “ex vivo assays”. Explants were split into equal pieces (100 mg), treated with or without acetylcholine (ACh) for 30 min. Afterwards RNA was isolated and cDNA was amplified by real time PCR. We selected adipocytes progenitors (CD36, PREF1, COL1A1), adipocytes markers (ADIPO, FABP4), muscarinic (muscarinic receptor type 2 (CHRM2) and 3 (CHRM2)) and β-adrenergic receptors (ABRD1, ABRD2 and ABRD3). Gene expression was represented regarding ACTB as 2HK/GEN.

Results

The stromal vascular cells (SVC) from subcutaneous fat (SAT) had higher expression levels of CD36, PREF1 and COL1A1 than SVC from epicardial fat (EAT). It explains the higher adipocytes markers after adipogenesis induction in SAT than EAT cells. However, an upregulation of fibroblasts markers was detected on EAT. The levels of CD36 and PREF1 in SVC were associated with higher adipogenesis. Although CHRM2 was higher in EAT than SAT SVC, the adipogenesis induction upregulated only CHRM3 (1.48±0.065 vs 1.42±0.036 a.u.) in EAT cells. Thus, this receptor was associated with adipocytes markers in epicardial fat (r=0.777 for CD36 and r=0.746 for FABP4) and incremented in epicardial fat biopsies from patients who were taken β-blockers (1.61±0.011 n=10 vs 1.54±0.097 a.u. n=9; p=0.05) and modulated by ACh treatment (p=0.05).

Conclusions

Our results showed that CD36 and PREF1 in epicardial SVC are adipocytes progenitors. The higher presence of adipocytes markers is associated with higher levels of muscarinic receptor (CHRM3), which are upregulated in epicardial fat from patients who were taken β-blockers and modulated by cholinergic activity. Because a metabolic and lipolytic dysfunction was associated with CHRM3, the sympathetic modulation might play a role in the epicardial adipocytes genesis. Further studies are needed to understand if this mechanism might improve or not future cardiovascular events.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ISCIII (PFIS2020)

P4464Significative role of edoxaban on endotelial cell functions

Background

Edoxaban is a new oral anticoagulant with factor X activated (FXa) inhibition properties. It is approved for the prevention of ictus and embolism in patients with atrial fibrillation and for the treatment of venous thrombosis and lung embolism. However, little is known about its effects on endothelial cell functions.

Objectives

To study the edoxaban effects on key endothelial functions as proliferation, wound-healing, angiogenesis and peripheral blood mononuclear cells (PBMCs) adhesion.

Methods

Human umbilical endothelial cells (HUVECs) were obtained from donated umbilical cords after signed informed consent of the mothers. Cell proliferation and viability were measured by a real-time cell analyzer by noninvasive electrical impedance monitoring. Migration was study in wound-healing assays. Angiogenesis was measured after 16 hours of HUVECs' seeding in a three dimensional matrix and PBMCs adhesion to HUVECs' monolayers was assessed in the presence or in the absence of edoxaban and/or FXa. Measurements on each assay was compared between control conditions and edoxaban's or FXa's treatments and between treatments with FXa and the combination of FXa and edoxaban.

Results

Edoxaban (1 Nm – 1 μm) was a safe, non-toxic molecule for HUVECs. It significantly promoted HUVECs' growth at concentrations between 10–500 Nm, been the maximal response at 100 nM. The proliferative effect of edoxaban 100 nM was also observed in the presence of FXa 9 nM, which also induced proliferation by itself. In spite of this proliferative effect, edoxaban (50–100 nM) did not increased healing (cells' migration) after a wound, but counteracted the healing effects of FXa 9 nM. Edoxaban (100–500 nM) alone did not influence angiogenesis, but partially restore the anti-angiogenic effect of FXa on HUVECs. Finally, and very interestingly, edoxaban (50–500 nM) significantly inhibited PBMCs adhesion to endothelial cells' monolayers, and even blocked the FXa (50 nM)- and tumor necrosis factor (TNF; 10μg/ml)-induced adhesion.

PBMCs adhesion to endothelial cells

Conclusions

Edoxaban is a safe and proliferative-inducer drug in endothelial cells in vitro. It counteracts the anti-angiogenic and pro-migratory effects of FXa on HUVECs, but more importantly, edoxaban significantly reduced PBMCs adhesion to endothelial cells monolayers in comparison to control experiments and compared to stimulated cells, independently of the pro-inflammatory drug used.

Acknowledgement/Funding

Daiichi-Sankyo España S.A.U.