Overview

Endothelial dysfunction (ED) is characterized by a shift of the endothelium actions toward reduced vasodilation, a proinflammatory state, and prothrombotic properties. An early event associated with most forms of CVD and its risk factors, ED also provides a link between CVD and risk of future CVD events.

WP4 provides an integrated and interdisciplinary basic and clinical approach to study:

• the prognostic role of circulating endothelial cells (CEC) and endothelial progenitor cells (EPC) at short- to mid-term follow-up as biomarkers for endothelial repair after an acute CV event;
• possible roles of cell microparticles and inflammation biomarkers in early detection of renal graft and ED;
• molecular mechanisms in menopause- and diet-associated ED, and
• the role of aging in vascular inflammation.

Project 1:
Endothelial progenitor cells as biomarkers for endothelial repair after CVD. Coordinator: G Escolar

CEC and EPC are markers of endothelial damage and repair. The general aim is to evaluate the prognostic value of CEC/EPC in the acute phase of CV events. The reparative potential of isolated EPCs will be estimated in cell cultures and the potential role of CEC/EPC in ventricular remodelling after acute myocardial infarction will be assessed. Impact of atheroprotective factors/therapies such as statins will be weighed. Other biomarkers of endothelial damage and repair, such as ADAMTS-13, adhesion receptors and acute markers of endothelial activation, also will be explored.

Project 2:
Renal graft and endothelial dysfunction by levels of endothelial cell microparticles and inflammation biomarkers. Coordinator: C Hermenegildo

Kidney disease is an accelerated model of atherosclerosis. Endothelial microparticles (EMP) could help to prevent early renal graft dysfunction. In a cohort of 100 kidney transplantation (KT) patients, we will study whether renal and CV risk factor status in the recipient after 12 months post KT can be predicted by inflammatory response markers (IRM) and EMP levels in recipient pre-KT, and also in an endothelial cell culture from a cadaver organ donor's aorta exposed to recipient serum. Pre-transplant determination in recipient will include IRM levels using x-MAP/MAG technology and of EMP using flow cytometry, and also in endothelial cell cultures exposed to recipient plasma, and in recipient plasma at 6 and 12 months. Endothelial function will be assessed in cell culture, and with hyperemia testing reactive to brachial artery vasoconstriction, pre-transplantation and at 6 & 12 months.

Project 3:
Study of the mechanisms for menopause- and diet-associated endothelial dysfunction. Coordinator: C Hermenegildo

Post-menopausal women have greater CVD risk, which has been largely associated to decreased estrogen levels but also to changes in other sex hormones or to metabolic changes (deregulation of energy balance, fat distribution and insulin sensitivity). Our aim is to determine molecular mechanisms for menopause- and diet-associated ED (induced by vasoactive peptides and metabolic syndrome) and the effects of dietary polyphenols in ED. Animal and cellular models will be used to study the role of nitric oxide and reactive oxygen species (ROS) systems. We will assess the endothelium-dependent relaxation to acetylcholine and other vasoactive compounds in male and female rodents vascular rings. In vascular samples and endothelial-cultured cells exposed to sex hormones and polyphenols, we will assess ROS; gene and protein expression of eNOS, caveolin-1 and HSP90; and AKT and eNOS phosphorylation.

Project 4:
Impact of aging on vascular inflammation. Coordinator: J Tamargo

Onset and progression of CVD has long been considered to be age-related. Our aim is to determine:

a) the role of aging on vascular structure and function (responses to vasoactive agents and endothelial mediators), antioxidant defence systems and biomarkers of endothelial dysfunction and inflammation; and

b) how diet, sex and time of menopause affects aging-associated effects on biomarkers and vascular function.

We are interested in determining how aging may influence vascular responses to vasoactive agents and endothelial mediators, and in protein expression in vascular wall, platelets and plasma from patients with CVDs.