Postprandial Hypertriglyceridemia Increases Circulating Levels of Endothelial Cell Microparticles

Abstract

Background-This study evaluated a possible relationship between levels of endothelial microparticles (EMPs), known to be a sensitive indicator of endothelial disturbance, and changes in postprandial lipid levels in healthy volunteers after a low-or high-fat meal. Methods and Results-Eighteen healthy subjects without known cardiovascular risk factors were evaluated. Lipid and EMP levels were measured before and 1 and 3 hours after a single low-or high-fat isocaloric meal. The low-fat meal had no significant postprandial effect on EMPs or lipids compared with fasting levels. In contrast, a single high-fat meal significantly increased EMP levels after 1 and 3 hours, from 389Ϯ54 (thousands per milliliter) when fasting to 541Ϯ139 (Pϭ0.0002) and 677Ϯ159 (PϽ0.0001), respectively, and correlated with a postprandial elevation in serum triglycerides. Conclusions-A single high-fat meal led to a significant elevation of plasma EMP levels in healthy, normolipidemic subjects and correlated with a postprandial elevation of serum triglycerides. 4,5 Hypertriglyceridemia has been shown to be an independent risk factor for coronary artery disease, 6,7 and increasing evidence suggests that postprandial hyperlipidemia contributes to the development of atherosclerosis and coronary artery disease. 8 -11 Moreover, several studies have demonstrated that postprandial hypertriglyceridemia can impair endothelial function, suggesting a role for triglycerides in the initiation and progression of atherosclerosis. [12][13][14] In vitro activation or apoptosis of cultured ECs induces the release of endothelial microparticles (EMPs). 15 EMPs in plasma exhibit the same antigenic markers and are detected and counted by flow cytometry, providing information on the degree of endothelial injury 16 -18 and even on the nature of the damage. 15 High levels of EMPs were reported in patients with thrombotic thrombocytopenic purpura, 16 preeclampsia, 17 acute coronary syndromes, 18,21 malignant hypertension, 19 multiple sclerosis, 20 and atherosclerotic plaques, 22 implicating EMPs as a marker of endothelial damage.In this article, we demonstrate a direct correlation between endothelial disturbance, measured by plasma EMP levels, and postprandial changes in serum triglycerides in healthy individuals after a single high-fat meal. No changes in EMP levels or serum lipids were observed after an isocaloric low-fat meal. These results suggest a link between postprandial hyperlipidemia and injury of the blood vessel wall. Methods Study SubjectsWe enrolled a total of 18 (10 male, 8 female; mean age, 26Ϯ3.8 years) healthy normolipidemic volunteers randomly selected from the medical center house staff. Subjects were nonobese, with a mean body mass index of 23Ϯ2.3 kg/m 2 , and normoglycemic, with a mean insulin level of 10Ϯ14 IU/mL. Subjects with dyslipidemia were excluded. The study protocol was approved and performed under the guidelines of our Institutional Review Board. Informed consent was obtained from each individual. Diet ProtocolThe diet protocol cons...

Microparticles as Biomarkers of Vascular Dysfunction in Metabolic Syndrome and its Individual Components

“…In this research, Ferreira et al [62] showed that a single high-fat meal significantly increased endothelial microparticle levels after one and three hours and positively correlated with a postprandial elevation in serum triglycerides. Elevated postprandial plasma triglycerides are an established risk factor for cardiovascular disease [63] and several reports have indicated that increased postprandial hypertriglyceridemia can impair endothelial function in normolipidaemic subjects [64,65].…”

“…The levels of circulating endothelial microparticles were shown to increase very quickly in relation a postprandial increase in triglycerides in normo-lipidaemic subjects [62].…”

Endothelial microparticles correlate with erectile dysfunction in diabetic men

“…An increase in EMP levels has been demonstrated in patients with cardiovascular disease, such as acute coronary syndromes, diabetes, hypertension and hypertriglyceridemia. [19][20][21][22][23] Microparticles can also influence endothelial functions: microparticles from patients with acute coronary syndromes directly impaired endothelium-dependent vasodilatation in rat aorta rings, presumably by inhibition of the nitric oxidemediated signal transduction. 9,10 Although microparticles are elevated in condition of endothelial 24 Endothelial cell dysfunction may be detected clinically by measuring impairment of endotheliumdependent vasodilation 25 or by determining the plasma levels of circulating soluble markers.…”

Short-term very low-calorie diet in obese females improves the haemostatic balance through the reduction of leptin levels, PAI-1 concentrations and a diminished release of platelet and leukocyte-derived microparticles

“…However, we could not exclude that the diet-reduction on cholesterol and triglycerides levels or the lowering of arterial hypertension may contribute to a diminished release of MPs. In the literature, several papers have emphasised that the ingestion of typical western diet could contribute to the shedding of endothelial-derived MPs, [35][36][37] or associated tissue factor activity 38 whereas the impact of fat ingestion on leukocyte-derived MPs levels is up to now not characterized. In addition, we could not exclude that the lowering of blood pressure could contribute to reduce platelet shedding through decrease shear stress.…”