Venous thromboembolic disease (VTD) is a public health problem. We recently reported that endothelial colony-forming cells (ECFCs) derived from endothelial cells (EC) (ECFC-ECs) from patients with VTD have a dysfunctional state. For this study, we proposed that a dysfunctional status of these cells generates a reduction of its proliferative ability, which is also associated with senescence and reactive oxygen species (ROS). Human mononuclear cells (MNCs) were obtained from peripheral blood from 40 healthy human volunteers (controls) and 50 patients with VTD matched by age (20−50 years) and sex to obtain ECFCs. We assayed their proliferative ability with plasma of patients and controls and supernatants of cultures from ECFC-ECs, senescence-associated β-galactosidase (SA-β-gal), ROS, and expression of ephrin-B2/Eph-B4 receptor. Compared with cells from controls, cells from VTD patients showed an 8-fold increase of ECFCs that emerged 1 week earlier, reduced proliferation at long term (39%) and, in passages 4 and 10, a highly senescent rate (30±1.05% vs. 91.3±15.07%, respectively) with an increase of ROS and impaired expression of ephrin-B2/Eph-4 genes. Proliferation potential of cells from VTD patients was reduced in endothelial medium [1.4±0.22 doubling population (DP)], control plasma (1.18±0.31 DP), or plasma from VTD patients (1.65±0.27 DP). As compared with controls, ECFC-ECs from individuals with VTD have higher oxidative stress, proliferation stress, cellular senescence, and low proliferative potential. These findings suggest that patients with a history of VTD are ECFC-ECs dysfunctional that could be associated to permanent risk for new thrombotic events.

The renin–angiotensin system plays an important role in the regulation of blood pressure and the development of coronary artery disease. The aim was to examine the association of the insertion deletion in the angiotensin-converting enzyme gene, M235T and T174M polymorphisms in the angiotensinogen gene with ST elevation acute myocardial infarction (STEAMI) in young Mexican population. We analyzed 242 unrelated patients with STEAMI 45 or less years of age, admitted to a cardiovascular intense care unit, and 242 individuals without STEAMI matched by age and sex, recruited from January 2006 and June 2013. The polymorphisms insertion deletion, M235T and T174M were determined in all participants by a polymerase chain-reaction-restriction fragment length polymorphism assay. There was a significant difference in the insertion deletion genotype distribution between two groups (P = 0.03) and a higher percentage of the T allele M235T polymorphism in the group of STEAMI patients (P = 0.02). The T174M polymorphism was not associated (P = 0.08). The insertion deletion and M235T polymorphisms, smoking, hypertension, familial history of cardiovascular disease and dyslipidemia were independent risk factors for STEAMI. Our results identified that the D allele from the insertion deletion and M235T but not T174M polymorphisms represent an independent risk factor for STEAMI in young Mexican population.

Chronic Myeloid Leukemia (CML) originates in a leukemic stem cell that resides in the bone marrow microenvironment, where they coexist with cellular and non-cellular elements. The vascular microenvironment has been identified as an important element in CML development since an increase in the vascularization has been suggested to be related with poor prognosis; also, using murine models, it has been reported that bone marrow endothelium can regulate the quiescence and proliferation of leukemic stem and progenitor cells. This observation, however, has not been evaluated in primary human cells. In this report, we used a co-culture of primitive (progenitor and stem) CML cells with endothelial colony forming cells (ECFC) as an in vitro model to evaluate the effects of the vascular microenvironment in the leukemic hematopoiesis. Our results show that this interaction allows the in vitro maintenance of primitive CML cells through an inflammatory microenvironment able to regulate the proliferation of progenitor cells and the permanence in a quiescent state of leukemic stem cells.