Mediterranean-Style Diet Effect on the Structural Properties of the Erythrocyte Cell Membrane of Hypertensive Patients

Abstract

Abstract-A currently ongoing randomized trial has revealed that the Mediterranean diet, rich in virgin olive oil or nuts, reduces systolic blood pressure in high-risk cardiovascular patients. Here, we present a structural substudy to assess the effect of a Mediterranean-style diet supplemented with nuts or virgin olive oil on erythrocyte membrane properties in 36 hypertensive participants after 1 year of intervention. Erythrocyte membrane lipid composition, structural properties of reconstituted erythrocyte membranes, and serum concentrations of inflammatory markers are reported. After the intervention, the membrane cholesterol content decreased, whereas that of phospholipids increased in all of the dietary groups; the diminishing cholesterol:phospholipid ratio could be associated with an increase in the membrane fluidity. Moreover, reconstituted membranes from the nuts and virgin olive oil groups showed a higher propensity to form a nonlamellar inverted hexagonal phase structure that was related to an increase in phosphatidylethanolamine lipid class. These data suggest that the Mediterranean-style diet affects the lipid metabolism that is altered in hypertensive patients, influencing the structural membrane properties. The erythrocyte membrane modulation described provides insight in the structural bases underlying the beneficial effect of a Mediterranean-style diet in hypertensive subjects. Key Words: Mediterranean diet Ⅲ lipids Ⅲ membrane structure Ⅲ cardiovascular disease Ⅲ hypertension C ardiovascular disease constitutes the main cause of death in industrialized countries, 1 and hypertension is one of the main modifiable cardiovascular risk factors, especially in the elderly. 2 Healthy diet and lifestyle constitute the first steps in the guidelines for management of hypertension. 3 In this context, the type and amount of dietary lipids influence the lipid composition of cell membranes 4,5 and modulate the interactions with proteins involved in the regulation of blood pressure. 6 Thus, the changes in membrane properties induced by dietary lipids may have important consequences on the blood pressure regulation.The Mediterranean-style diet (MD) is characterized by a high consumption of virgin olive oil (VOO) and nuts, which are rich natural sources of oleic (18:1; n-9) and ␣-linolenic (18:3; n-3) acids, respectively. The Prevencion con Dieta Mediterranea (PREDIMED) Study is a large-scale, randomized trial aimed at assessing the effects of a MD enriched with VOO or nuts on primary prevention of cardiovascular disease in patients at high risk for coronary heart disease. The results of the 3-month intervention on the first 772 patients entering the study showed that, compared with a low-fat diet, the MD rich in VOO or nuts reduced systolic blood pressure and serum total cholesterol and triglyceride concentrations and increased serum high-density lipoprotein cholesterol concentration. 7 Although there is evidence indicating that dietary lipids can have a positive effect on cardiovascular risk factors, the mechani...

Protection from hypertension in mice by the Mediterranean diet is mediated by nitro fatty acid inhibition of soluble epoxide hydrolase

“…This mechanism for the endogenous generation of a sEH inhibitor providing cardiovascular protection is fully consistent with the actions of synthetic sEH inhibitors (41,42). The findings of this study may provide an explanation, at least in part, for the findings of the Prevención con Dieta Mediterránea (PREDIMED) multicenter randomized trial (43), which showed a Mediterranean diet supplemented with extra virgin olive oil or nuts reduced the incidence of major cardiovascular events.…”

Adherence to the Mediterranean diet and albuminuria levels in Greek adolescents: data from the Leontio Lyceum ALbuminuria (3L study)

“…This is the first study showing that in healthy adolescents, there is an inverse relation of KIDMED index with albuminuria. One could suggest that the protective to the endothelium and anti-atherosclerotic properties of the Mediterranean diet (Willett et al, 1995;Trichopoulou and Lagiou, 1997;Panagiotakos et al, 2003Panagiotakos et al, , 2007Psaltopoulou et al, 2004;Serra-Majem et al, 2004;Trichopoulos and Lagiou, 2004;Estruch et al, 2006;Karlin et al, 2008;Barceló et al, 2009; Nú ñez-Có rdoba et al, 2009) could be the pathophysiological explanation for the observed relation of the level of adherence to this favorable diet and decreased urinary albumin excretion. It is also established that the Mediterranean food pattern is related to reduced inflammatory activation (Carter et al, 2010) that in its own turn is associated with attenuated levels of albuminuria as previously shown (Tsioufis et al, 2004;Tsioufis et al, 2005).…”

Health Benefits of Nut Consumption

“…This has not been observed in the usually small-sized clinical studies performed to date, but the larger PREDIMED trial did show significant reductions in both systolic and diastolic blood pressure after the nut-supplemented Mediterranean diet compared with the control diet [80]. A recent report of the PREDIMED trial provides an insight into the possible mechanism of this antihypertensive effect by showing that the nut diet was associated with reduced cholesterol: phospholipid ratios of erythrocyte membranes, which would translate into an increase of membrane fluidity [128]. Possibly future adequately powered studies might uncover a true antihypertensive effect of nut intake.…”