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Richard C.,Laval University | Couture P.,Laval University | Couture P.,Lipid Research Center | Desroches S.,Laval University | And 2 more authors.
Nutrition, Metabolism and Cardiovascular Diseases | Year: 2011

Background and aims: No study has yet examined how weight loss modifies the impact of the Mediterranean diet (MedDiet) on cardiovascular risk factors in men with the metabolic syndrome (MetS). The objective of the study was to assess the efficacy of MedDiet, with and without weight loss, to modify the cardiometabolic risk profile of male patients with MetS. Methods and results: Twenty-six men aged between 24 and 62 years with the MetS consumed a North American control diet for 5 weeks followed by a 5-week MedDiet, both under weight-maintaining conditions. Participants then underwent a 20-week weight loss period, after which they consumed the MedDiet for five weeks under weight stable conditions. Body weight was reduced by 10.2% ± 2.9% after the weight loss period (p < 0.001). All foods were provided to participants during the weight stable phases of the study. The MedDiet in the absence of weight loss decreased total plasma cholesterol (C) (-7.1%), LDL-C (-9.3%) and the total/HDL-C ratio (-6.5%) compared to the control diet (all p < 0.04). The MedDiet combined with weight loss led to reductions in systolic blood pressure (-4.7%), diastolic blood pressure (-7.7%), triglycerides (-18.2%), ApoB (-10.7%), fasting glucose (-4.2%) and insulin (-29.9%) compared to the control diet (all p < 0.001). Conclusion: The MedDiet in the absence of weight loss leads to significant changes in plasma cholesterol concentrations but has little effects on other cardiometabolic risk factors associated with the MetS in men. © 2010 Elsevier B.V.


Borel A.-L.,University of Québec | Nazare J.-A.,University of Québec | Smith J.,University of Québec | Almeras N.,University of Québec | And 6 more authors.
Obesity | Year: 2012

Excess visceral adipose tissue (VAT) is associated with an increased cardiometabolic risk. The study examined whether changes in cardiometabolic risk markers after a 1-year lifestyle intervention in viscerally obese men were associated with changes in VAT or with changes in subcutaneous abdominal adipose tissue (SAT). The relative contributions of changes in global adiposity vs. changes in cardiorespiratory fitness to changes in VAT were also quantified. One hundred and forty four men were selected on the basis of an increased waist circumference (90 cm) associated with dyslipidemia (triglycerides ≥1.69 and/or high-density lipoprotein (HDL)-cholesterol <1.03 mmol/l); 117 men completed the 1-year intervention which consisted in a healthy eating, physical activity/exercise program. Body weight, body composition, and fat distribution were assessed by anthropometry and dual-energy X-ray absorptiometry (DEXA)/computed tomography. Cardiorespiratory fitness, plasma adipokine/inflammatory markers, fasting lipoprotein-lipid profile, and oral glucose tolerance test (OGTT) were assessed. VAT volume decreased by 26%, cardiorespiratory fitness improved by 20% (P< 0.0001) after 1 year. Plasma adipokine/inflammatory markers, lipids/lipoproteins, and glucose homeostasis were improved. One-year changes in triglyceride (r = 0.29), apolipoprotein B (r = 0.21), 120-min OGTT-glucose (r = 0.27), and fasting insulin (r = 0.27) levels correlated with changes in VAT (all P< 0.05) after adjustment for changes in SAT. Using a multilinear regression model, VAT reduction was independently associated with SAT reduction and with improvement in cardiorespiratory fitness (R 2 = 0.58, P< 0.0001). Therefore, this healthy eating-physical activity/exercise program improved the cardiometabolic risk profile of viscerally obese men in relation to the reduction of VAT. Furthermore, the reduction in VAT was independently related to the reduction in global adiposity and to the improvement in cardiorespiratory fitness. © 2011 The Obesity Society.


Tremblay A.J.,Laval University | Tremblay A.J.,Lipid Research Center | Lamarche B.,Laval University | Deacon C.F.,Copenhagen University | And 3 more authors.
Metabolism: Clinical and Experimental | Year: 2014

Inflammation and endothelial dysfunction are increasingly being recognized as key etiological factors in the development of atherosclerosis and subsequent cardiovascular disease. These pro-atherogenic factors are strongly correlated and are often found to co-segregate in patients with type 2 diabetes. The impact of sitagliptin, a selective inhibitor of dipeptidyl peptidase-4, on inflammation and markers of endothelial function remains to be fully characterized. Objective The objective of the present study was to examine the effects of treatment with sitagliptin on the plasma levels of various markers of low-grade inflammation and cell adhesion molecules in patients with type 2 diabetes. Methods and results Thirty-six subjects with type 2 diabetes (30 men/6 postmenopausal women with a mean age of 58.1 ± 6.4 years and a body mass index of 30.7 ± 4.9 kg/m2) were recruited into this double-blind, cross-over study using sitagliptin (100 mg/d) or placebo, each for a 6-week period, including a 4-week washout period between the two phases. Blood samples were taken at the end of each phase of treatment. Compared with placebo, treatment with sitagliptin significantly reduced the plasma levels of C-reactive protein (CRP) (44.9%, P = 0.006), interleukin (IL)-6 (24.7%, P = 0.04), IL-18 (7.3%, P = 0.004), secreted phospholipase-A2 (sPLA 2) (12.9%, P = 0.04), soluble intercellular adhesion molecule-1 (5.3%, P = 0.002), and E-selectin (5.9%, P = 0.005). A significant inverse correlation was found between changes in glucagon-like peptide-1 (GLP-1) and changes in CRP levels (r = 0.41, P = 0.01) following sitagliptin therapy. Sitagliptin therapy had more pronounced effects in subjects with higher levels of inflammatory markers and cell adhesion molecules compared with subjects with lower levels. Conclusions Treatment with sitagliptin for 6 weeks reduced plasma markers of low-grade inflammation and cell adhesion molecules, most likely by increasing plasma GLP-1 levels and improving glucose-insulin homeostasis. These beneficial effects of sitagliptin might represent a further advantage in the management of diabetes and its proatherogenic comorbidities. © 2014 Elsevier Inc.


Tremblay A.J.,Lipid Research Center | Tremblay A.J.,Laval University | Lamarche B.,Laval University | Guay V.,Laval University | And 4 more authors.
American Journal of Clinical Nutrition | Year: 2013

Background: The modulation of cholesterol and fatty acid homeostasis by dietary fatty acids is thought to be mediated by changes in the expression of key intestinal genes involved in lipoprotein metabolism. However, the short-term effect of dietary fat intake on the expression of these genes has not been fully investigated in humans. Objective: To test whether short-term changes in dietary fatty acid intake affect the expression of key intestinal genes involved in lipoprotein metabolism, we conducted a randomized, double-blind, crossover study in 12 nonobese, healthy men with normal plasma lipid profiles. Design: Participants were subjected to the following 2 intensive 3-d dietary interventions under isocaloric conditions: 1) a high-fat diet (37% of energy from fat and 50% of energy from carbohydrates) and 2) a low-fat diet (25% of energy from fat and 62% of energy from carbohydrates). Expressions of key genes involved in lipoprotein metabolism were compared by using real-time polymerase chain reaction quantification on duodenal biopsy specimens obtained in a fasting state after each diet. Results: After the 3-d high-fat diet, plasma cholesterol, LDL cholesterol, and HDL cholesterol concentrations were significantly higher than concentrations observed after the low-fat diet was consumed. The high-fat diet also resulted in significant increases in the intestinal messenger RNA expression of several key genes involved in lipoprotein metabolism. Plasma triglycerides and apolipoprotein B-48 concentrations were significantly lower after the high-fat diet than after the low-fat diet. Conclusion: These findings suggest that short-term exposure to a high-fat diet upregulates the expression of key genes involved in lipid and lipoprotein metabolism at the enterocyte level. This trial was registered at clinicaltrials.gov as NCT01806441. Copyright © 2013 American Society for Nutrition.


Conway V.,Laval University | Couture P.,Laval University | Couture P.,Lipid Research Center | Richard C.,Laval University | And 3 more authors.
Nutrition, Metabolism and Cardiovascular Diseases | Year: 2013

Background and aims: Sphingolipids (SL) are important components of the milk fat globule membrane (MFGM) found in buttermilk. While studies in animal models suggest that dietary SL may have cholesterol-lowering properties, data in human are lacking. The aim of this study was to investigate the impact of buttermilk consumption on plasma lipids and surrogate markers of cholesterol (C) homeostasis in humans. Methods and results: Men and women (n=34) with serum LDL-C <5.0mmol/L at screening (mean LDL-C=3.8mmol/L) were recruited in this double-blinded randomized crossover placebo controlled study. Their diets were supplemented with 45g/d of buttermilk and with 45g/d of a macro/micronutrient matched placebo (4 weeks each in random order). Serum lipid concentrations and surrogate markers of cholesterol homeostasis were measured post diet and compared using mixed models for repeated measures. Consumption of buttermilk led to reduction in serum cholesterol (-3.1%, P=0.019), LDL-C (-3.1%, P=0.057) and triacylglycerol (-10.7%, P=0.007). Buttermilk consumption increased plasma lathosterol concentrations (+12.1%, P=0.001), but multiple regression analysis indicated that variations in β-sitosterol concentrations (P=0.002) were the only significant predictor of the LDL-C response to buttermilk consumption. Conclusion: Buttermilk consumption may be associated with reduced cholesterol concentrations in men and women, primarily through inhibition of intestinal absorption of cholesterol. Registration number: This trial is registered at clinicaltrials.gov as NCT01248026. © 2013 Elsevier B.V.


Conway V.,Laval University | Couture P.,Laval University | Couture P.,Lipid Research Center | Gauthier S.,Laval University | And 2 more authors.
Nutrition | Year: 2014

Objectives: Milk fat globule membrane (MFGM) found in buttermilk is rich in unique bioactive proteins. Several studies suggest that MFGM proteins possess biological activities such as cholesterol-lowering, antiviral, antibacterial, and anticancer properties, but data in humans are lacking. Furthermore, to our knowledge, no study has yet investigated the antihypertensive potential of MFGM proteins from buttermilk. The aim of this study was to investigate the effects of buttermilk consumption on blood pressure and on markers of the renin-angiotensin-aldosterone (RAS) system in humans. Methods: Men and women (N = 34) with plasma low-density lipoprotein cholesterol < 5 mmol/L and normal blood pressure (< 140 mm Hg) were recruited in this randomized, double-blind, placebo-controlled, crossover study. Their diets were supplemented with 45 g/d of buttermilk and with 45 g/d of a macro-/micronutrient-matched placebo in random order (4 wk for each diet). Results: Buttermilk consumption significantly reduced systolic blood pressure (-2.6 mm Hg; P = 0.009), mean arterial blood pressure (-1.7 mm Hg; P = 0.015), and plasma levels of the angiotensin I-converting enzyme (-10.9%; P = 0.003) compared with the placebo, but had no effect on plasma concentrations of angiotensin II and aldosterone. Conclusion: Short-term buttermilk consumption reduces blood pressure in normotensive individuals. © 2014 The Authors.


Richard C.,Laval University | Couture P.,Laval University | Couture P.,Lipid Research Center | Desroches S.,Laval University | And 2 more authors.
Journal of Lipid Research | Year: 2013

We investigated the effect of weight loss, independent of change in diet composition, on HDL and apoAI metabolism in men with metabolic syndrome (MetS). Subjects (19 men with MetS [NCEP-ATPIII]) were fed an isoenergetic Mediterranean-style diet for 5 weeks (all foods provided). Participants then underwent a 20-week free-living period during which they were counseled to restrict energy intake, after which they were again fed an isoenergetic Mediterranean-style diet for 5 weeks. At the end of the two controlled diets, participants received a single bolus of [5,5,5-2 H 3 ] L-leucine, and fasting blood samples were collected over a 96 h period. ApoAI kinetic was assessed using multicompartmental modeling of the tracer enrichment data. Participants achieved a 9.1 ± 2.8% reduction in body weight (P < 0.001). Weight loss resulted in an increase in plasma HDL-cholesterol (HDL-C) concentrations of 6.0% (P = 0.059) and HDL3-C of 7.9% (P = 0.045), attributable to a reduction in apoAI fractional catabolic rate (-7.8%; P = 0.046) with no change in apoAI production rate (2.2%; P = 0.58). These data indicate that weight loss, independent of variation in diet composition, increases plasma HDL primarily by delaying the catabolism of apoAI. Copyright © 2013 by the American Society for Biochemistry and Molecular Biology, Inc.


Guay V.,Laval University | Lamarche B.,Laval University | Charest A.,Laval University | Tremblay A.J.,Laval University | And 2 more authors.
Metabolism: Clinical and Experimental | Year: 2012

High-fat, low-carbohydrate diets have been shown to raise plasma cholesterol levels, an effect associated with the formation of large low-density lipoprotein (LDL) particles. However, the impact of dietary intervention on time-course changes in LDL particle size has not been investigated. To test whether a short-term dietary intervention affects LDL particle size, we conducted a randomized, double-blind, crossover study using an intensive dietary modification in 12 nonobese healthy men with normal plasma lipid profile. Participants were subjected to 2 isocaloric 3-day diets: high-fat diet (37% energy from fat and 50% from carbohydrates) and low-fat diet (25% energy from fat and 62% from carbohydrates). Plasma lipid levels and LDL particle size were assessed on fasting blood samples after 3 days of feeding on each diet. The LDL particles were characterized by polyacrylamide gradient gel electrophoresis. Compared with the low-fat diet, plasma cholesterol, LDL cholesterol, and high-density lipoprotein cholesterol were significantly increased (4.45 vs 4.78 mmol/L, P =.04; 2.48 vs 2.90 mmol/L, P =.005; and 1.29 vs 1.41 mmol/L, P =.005, respectively) following the 3-day high-fat diet. Plasma triglycerides and fasting apolipoprotein B-48 levels were significantly decreased after the high-fat diet compared with the low-fat diet (1.48 vs 1.01 mmol/L, P =.0003 and 9.6 vs 5.5 mg/L, P =.008, respectively). The high-fat diet was also associated with a significant increase in LDL particle size (255.0 vs 255.9 Å; P =.01) and a significant decrease in the proportion of small LDL particle (<255.0 Å) (50.7% vs 44.6%, P =.01). As compared with a low-fat diet, the cholesterol-raising effect of a high-fat diet is associated with the formation of large LDL particles after only 3 days of feeding. © 2012 Elsevier Inc. All rights reserved.


Lamarche B.,Laval University | Richard C.,Laval University | Couture P.,Laval University | Couture P.,Lipid Research Center | Desroches S.,Laval University
Obesity | Year: 2013

Objective: Intervention studies on the Mediterranean Diet (MedDiet) have often led to weight loss, which may have contributed to the purported anti-inflammatory effects of the MedDiet. To investigate the impact of the MedDiet consumed under controlled feeding conditions before (-WL) and after weight loss (+WL) on markers of inflammation in men with metabolic syndrome (MetS). Design and Methods: Subjects (N = 26, male, 24-65 years) with MetS first consumed a North American control diet for 5 weeks followed by a MedDiet for 5 weeks both in isocaloric feeding conditions. After a 20-week weight loss period in free-living conditions (10 ± 3% reduction in body weight, P < 0.01), participants consumed the MedDiet again under isocaloric-controlled feeding condition for 5 weeks. Results: MedDiet - WL significantly reduced plasma C-reactive protein (CRP) concentrations (-26.1%, P = 0.02) and an arbitrary inflammatory score (-9.9%, P = 0.01) that included CRP, interleukin-6 (IL-6), IL-18, and tumor necrosis factor-α (TNF-α) compared with the control diet. The MedDiet + WL significantly reduced plasma IL-6 (-20.7%) and IL-18 (-15.6%, both P ≤ 0.02) concentrations compared with the control diet but had no further significant impact on plasma CRP concentration. Participants with a reduction in waist circumference -8.5 cm after MedDiet + WL showed significantly greater reductions in inflammation markers than those with a change in waist circumference <8.5 cm. Conclusions: Thus, consuming MedDiet even in the absence of weight loss significantly reduces inflammation. However, the degree of waist circumference reduction with weight loss magnifies the impact of the MedDiet on other markers of inflammation associated with MetS in men.


Rudkowska I.,Lipid Research Center
Maturitas | Year: 2010

The proportion of elderly is growing worldwide. This trend is in parallel to an increase in diseases, such as cardiovascular disease (CVD). Plant sterols and stanols (PS) consumption is known to decrease low-density lipoprotein-cholesterol (LDL-C) levels by 5-15%, and thus lower CVD risk. Yet, the effect of PS on LDL-C levels differs between individuals. Furthermore, PS have recently been investigated for the prevention of other age-related diseases. The objective of this review is to examine the benefits of PS on CVD as well as ageing-associated diseases. PS have the ability to significantly lower LDL-C; yet, the large inter-individual variability in the lowering of LDL-C may be due to subject characteristics, food matrix of PS, dose of PS, dietary background, frequency of intake of PS, the additive effect of other foods or drugs, as well as genetic factors. Further, PS may also have other potential beneficial effects including anti-atherogenic, anti-inflammatory, antioxidant and anti-cancer activities. Overall, dietary intervention strategies, such as incorporating PS into a healthy diet, should be recommended and implemented in older adult populations in order to prevent ageing-associated diseases and hence promote healthy ageing. © 2010 Elsevier Ireland Ltd. All rights reserved.

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