[Impact of sickle cell trait on arterial stiffness in African subjects]. / Impact du trait drépanocytaire sur la rigidité artérielle des sujets africains.

Sickle cell trait (SCT) is the benign condition of sickle cell disease. Often asymptomatic, the carriers of the sickle cell trait have hemorheological disturbances with increased oxidative stress compared to healthy subjects. These disturbances can lead to structural and functional changes in large vessels. The aim of the study was to measure arterial stiffness, an independent marker of subclinical atherosclerosis, SCT carriers compared to sickle cell anemia (SCA) subjects. Nine SCT carriers aged 32±9 years (7 men) were compared to 14 SCA subjects aged 29±9 years (2 men) and 22 control subjects aged 34±9 years (11 men) recruited by the National blood transfusion center (CNTS) in Dakar (Senegal). Arterial stiffness was assessed by measurement of the finger-toe pulse wave velocity (PWVft) using pOpmètre® (Axelife SAS-France). The cardiovascular risk (CVR) was assessed according to the Framingham Laurier score. The SCT carriers had a higher PWVft (m/s) than SCA subjects (8.2±2.2 vs 6.1±0.9m/s, P=0.004) but not different from that of healthy controls (8.2±2.2 vs 7.4±1.8m/s, P=0.33). Linear regression showed a positive relationship between PWVft and the pulse pressure (PP) (P˂0.001; r2=0.39; F=13.20). The results show that the SCT carriers have stiffer arteries than SCA subjects. Linear regressions adjusted for age, mean arterial pressure (MAP) and PP, showed that only age and PP were independently correlated with arterial stiffness in the entire population.

Mitochondria as potential targets of flavonoids: focus on adipocytes and endothelial cells.

Obesity is a major public health problem, resulting from an excess of energy storage and/or a default of energy expenditure leading to the increased occurrence of cardiovascular risk factors that favour the development of vascular complications. As a consequence, many studies are interested to find novel therapeutic chemical including flavonoids that appear to be promising natural compounds to treat obesity and its complications. Several in vitro studies addressed the mechanisms involved that might explain their beneficial effects, on adipocytes and endothelial cells, two cell types that play major role in obesity and its vascular complications. Besides the well-described antioxidant properties of flavonoids, at least a part of their beneficial effects on these cell types might be explained by their action on the regulation of mitochondrial function. In this review, we will therefore focus on the pathophysiological role of mitochondria in regulating endothelial and adipocyte functions. In addition, we will present some of the more promising flavonoids, important in human diet, including flavanols, flavonols, isoflavones, anthocyanins, flavanones and flavones; and their potential effects to improve endothelial or adipocyte functions via the mitochondria.