1.
Effect of an isoenergetic traditional Mediterranean diet on the high-density lipoprotein proteome in men with the metabolic syndrome.
Richard, C, Couture, P, Desroches, S, Nehmé, B, Bourassa, S, Droit, A, Lamarche, B
Journal of nutrigenetics and nutrigenomics. 2014;(1):48-60
Abstract
BACKGROUND/AIMS: The objective of this preliminary study was to examine the impact of the Mediterranean diet (MedDiet) on the high-density lipoprotein (HDL) proteome in men with the metabolic syndrome (MetS). METHODS Twenty-six men with the MetS first consumed a standardized baseline North American isoenergetic control diet (5 weeks) and then consumed an isoenergetic MedDiet (5 weeks), both in full feeding condition. The HDL fraction was isolated by ultracentrifugation at the end of each diet and the HDL proteome assessed by isobaric tags for relative and absolute quantitation and mass spectrometry. RESULTS Of all proteins identified within HDL, only 3 showed significant changes in relative abundance after the MedDiet versus the control diet, including a reduction in inflammation-related inter-α-trypsin inhibitor heavy chain H4 (fold change: 0.62) and hemoglobin subunits α (fold change: 0.40) and β (fold change: 0.46). Other HDL-bound proteins associated with functions related to lipid metabolism/cholesterol homeostasis, oxidation, coagulation, complement activation and immunity were unchanged after consumption of the MedDiet for 5 weeks. CONCLUSIONS Changes in the HDL proteome may explain, at least partly, the well-known anti-inflammatory effect ascribed to the MedDiet. Otherwise, short-term consumption of the MedDiet seems to have little impact on other features of the HDL proteome in men with the MetS.
2.
Effect of rosiglitazone on HDL metabolism in subjects with metabolic syndrome and low HDL.
Millar, JS, Ikewaki, K, Bloedon, LT, Wolfe, ML, Szapary, PO, Rader, DJ
Journal of lipid research. 2011;(1):136-42
Abstract
Treatment with the peroxisome proliferator-activated receptor γ agonist rosiglitazone has been reported to increase HDL-cholesterol (HDL-C) levels, although the mechanism responsible for this is unknown. We sought to determine the effect of rosiglitazone on HDL apolipoprotein A-I (apoA-I) and apoA-II metabolism in subjects with metabolic syndrome and low HDL-C. Subjects were treated with placebo followed by rosiglitazone (8 mg) once daily. At the end of each 8 week treatment, subjects (n = 15) underwent a kinetic study to measure apoA-I and apoA-II production rate (PR) and fractional catabolic rate. Rosiglitazone significantly reduced fasting insulin and high-sensitivity C-reactive protein (hsCRP) and increased apoA-II levels. Mean apoA-I and HDL-C levels were unchanged following rosiglitazone treatment, although there was considerable individual variability in the HDL-C response. Rosiglitazone had no effect on apoA-I metabolism, whereas the apoA-II PR was increased by 23%. The change in HDL-C in response to rosiglitazone was significantly correlated with the change in apoA-II concentration but not to changes in apoA-I, measures of glucose homeostasis, or hsCRP. Treatment with rosiglitazone significantly increased apoA-II production in subjects with metabolic syndrome and low HDL-C but had no effect on apoA-I metabolism. The change in HDL-C in response to rosiglitazone treatment was unrelated to effects on apoA-I, instead being related to the change in the metabolism of apoA-II.
3.
Effect of a short-term diet and exercise intervention on inflammatory/anti-inflammatory properties of HDL in overweight/obese men with cardiovascular risk factors.
Roberts, CK, Ng, C, Hama, S, Eliseo, AJ, Barnard, RJ
Journal of applied physiology (Bethesda, Md. : 1985). 2006;(6):1727-32
Abstract
There is significant debate regarding high-density lipoprotein cholesterol (HDL-C) and high-fiber, low-fat diets. The present study was designed to examine the effects of lifestyle modification on the inflammatory/anti-inflammatory properties of HDL in obese men (n = 22) with metabolic syndrome factors. Subjects were placed on a high-fiber, low-fat diet in a 3-wk residential program where food was provided ad libitum and daily aerobic exercise was performed. Fasting blood was drawn pre- and postintervention for serum lipids, lipid hydroperoxides, and the ability of subject HDL to alter low-density lipoprotein (LDL)-induced monocyte chemotactic activity (MCA) in a human artery wall coculture. Induction of MCA by control LDL in the absence of HDL was normalized to 1.0. Values >1.0 after HDL addition indicated proinflammatory HDL; values <1.0 indicated anti-inflammatory HDL. In addition, proteins involved in regulating HDL function, apolipoprotein A-I (apoA-I), paraoxonase 1 and 3, and platelet-activating factor acetylhydrolase were measured. After 3 wk, decreases in total-cholesterol, LDL-cholesterol, HDL-C, triglycerides, total cholesterol-to-HDL cholesterol ratio, and lipid hydroperoxides (all P < 0.05) were noted. The HDL inflammatory index decreased (P < 0.05) from pro- (1.14 +/- 0.11) to anti-inflammatory (0.94 +/- 0.09). ApoA-I level and paraoxonase activity did not change; however, platelet-activating factor acetylhydrolase activity increased (P < 0.05). Despite a quantitative reduction in HDL-C, HDL converted from pro- to anti-inflammatory. These data indicate that intensive lifestyle modification improves the function of HDL even in the face of reduced levels, suggesting increased turnover of proinflammatory HDL.