Circulating levels of endothelial function are modulated by dietary monounsaturated fat

Background: For the most part, the benefits of monounsaturated-rich diets ( MUFA-diet) have been related to their action on plasma lipid levels. Howeve r other non-lipidic effects could also be involved in their protective effe cts. One of these involves the decrease in plasma levels of plasminogen act ivator inhibitor type 1 (PAI-1), the main inhibitor of fibrinolysis. Given that the PAI-1 is of endothelial origin, one hypothesis is that the MUFA-di et could protect against CHD by modulating some endothelial components. Met hods and results: Healthy male subjects (n = 25) received three different c onsecutive diets, each lasting 28 days: a low fat NCEP-I-diet, with 28% cal ories as fat, 10% saturated fat (SAT), 12% monounsaturated (MUFA) and 6% po lyunsaturated (PUFA); a MUFA-diet, with 38% calories as fat, 10% SAT, 22% M UFA and 6% PUFA, and a SAT rich-diet (SAT-diet), with 38% calories as fat, 20% SATI 12% MUFA and 6% PUFA. After each dietary period, the plasma lipid profile was determined. including total cholesterol, HDL cholesterol, LDL c holesterol. total triglyceride, apo Al. apo B plasma levels and conjugated diene formation, after incubation of LDL particles with Cu 5 mu M/l. Endoth elial products measured in plasma were von Willebrand factor (VWF), E-selec tin, Thrombomodulin and Tissue Factor Pathway Inhibitor (TFPI) levels. We o bserved a decrease in VWF, PAI-1 and TFPI plasma levels and an increase in lag time of conjugated diene formation after the MUFA-diet. There was a pos itive correlation between the decreases in TFPI and VWF and the changes in total cholesterol, LDL-C, apo B plasma levels. The decrease in TFPI was neg atively correlated with the increase in lag time of conjugated diene format ion. PAI-1 plasma levels were positively correlated with total cholesterol, LDL-C and triglycerides and negatively correlated with HDL-C. Conclusions: Consumption of a Mediterranean-type MUFA-diet produces a decrease in plasm a levels of vWF, TFPI and PAI-1 plasma levels in young healthy males. Given that these substances are of endothelial origin, one could suggest that th e MUFA of the diet has a beneficial effect on endothelial function resultin g in protective changes against thrombogenesis. (C) 1999 Elsevier Science I reland Ltd. All rights reserved.