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BACKGROUND: Exacerbated postprandial lipemia is a risk factor for cardiovascular disease and is linked to insulin status. Limited data on the effect of dietary carbohydrate on postprandial lipoprotein accumulation are available. OBJECTIVE: We tested the hypothesis that dietary carbohydrates with different glucose availability alter postprandial lipoprotein metabolism differently in obese, insulin-resistant subjects. DESIGN: After an overnight fast, 9 subjects with central obesity and insulin resistance but normal triacylglycerolemia randomly ingested 2 test meals with comparable amounts of fat (28-29 g) and digestible carbohydrate (91-94 g) but with different quantities of slowly available glucose (SAG) in cereal products (17 or 2 g SAG/100 g for biscuits and wheat flakes, respectively). Blood samples were collected before and for 6 h after meal intakes. RESULTS: The postmeal 0-2-h areas under the curve (AUCs) for glycemia and insulinemia were significantly lower (P < 0.05) after the biscuit meal than after the flakes meal. Plasma triacylglycerol concentrations increased significantly after the flakes meal but not after the biscuit meal (1.5-fold higher 0-6-h AUC for the flakes meal). Apolipoprotein B-100 concentrations in the triacylglycerol-rich lipoprotein fraction increased significantly 2 h after the flakes meal but not after the biscuit meal (3-fold higher 0-6-h AUC for the flakes meal). Apolipoprotein B-48 concentrations increased (P < 0.05) 4 h after the flakes meal but not after the biscuit meal (2.3-fold higher 0-6-h AUC for the flakes meal). CONCLUSION: Mixed meals containing slowly digestible carbohydrate that induces low glycemic and insulinemic responses reduce the postprandial accumulation of both hepatically and intestinally derived triacylglycerol-rich lipoproteins in obese subjects with insulin resistance. Copyright © 2004 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Objective: To determine the postprandial lipaemia response before and after intervention with healthy diets in the Medi-RIVAGE cohort of subjects with moderate risk factors of CVD., Design: One hundred and thirty-five adults (fifty-two men and eighty-three women) followed either a Mediterranean-type (MED) diet or a low-fat American Heart Association-type diet in a parallel design for 3 months. At entry and after 3 months, lipids, glucose and insulin were measured in the fasting samples; TAG and apolipoprotein B48 (ApoB48; a marker of intestinally derived chylomicrons) levels were measured in the fasting and postprandial samples after a standard test meal., Results: The MED diet only lowered (P < 0·028) fasting TAG and both diets reduced TAG and ApoB48 levels 5 h after the test meal. The overall 5 h postprandial ApoB48 response (area under curve (AUC)/incremental AUC) was lowered after both diets but this effect was more marked after the MED-diet intervention. Whatever the TAG level at entry, normo- and hyper TAG subjects showed a reduction in the postprandial ApoB48 levels after 3-month diets. BMI at entry did not impact the effect of diets given subjects with BMI < or >25 kg/m2 showed reduced postprandial ApoB48. Men and women displayed comparable postprandial changes after dietary challenges., Conclusions: A MED diet appears efficient to improve postprandial lipaemia, a recently acknowledged CVD risk, in men and women at moderate cardiovascular risk.

Unlabelled: Lutein is recovered at high concentration in the human macula lutea. Recent studies suggest that this micronutrient might be implicated in prevention of age-related macular degeneration., Objective: to identify genes which affect blood and retina lutein concentrations among candidate genes (intestinal sterol transporters and carotenoid oxygenases)., Design: a comparative plus an observational study., Participants: twenty-nine healthy subjects for the comparative study and 622 subjects for the observational study., Intervention and Methods: all the participants were genotyped for single nucleotide polymorphisms (SNPs) in the candidate genes. Fasting plasma lutein concentrations were measured in all the participants and after 6 months' supplementation, with either a lutein-rich supplement or a placebo, in the 29 subjects who participated in the comparative study. Macular pigment optical density (MPOD), which is a measure of macula concentration of lutein, was measured before and after the dietary intervention in the 29 subjects. Associations between SNPs and plasma lutein and MPOD were assessed by partial least square (PLS) regression followed by univariate analysis. Observed associations between SNPs and plasma lutein were verified by haplotype-based association analysis in the cohort of 622 subjects., Main Outcome Measures: plasma lutein levels and MPOD., Results: six SNPs in four genes (ABCG8, BCMO1, CD36, and NPC1L1) explained 25% and 38% of the plasma and MPOD variance, respectively. Subjects with TT at the BCMO1 rs7501331 locus had lower (P < 0.05) plasma lutein than CT subjects. Subjects with CC at the CD36 rs13230419 locus had lower (P < 0.05) plasma lutein than subjects who carried a T allele. The association between CD36 and plasma lutein was confirmed in the cohort of 622 subjects. Subjects with TT at the BCMO1 rs7501331 locus had a higher (P < 0.05) MPOD, and subjects with GG at rs1761667 CD36 locus had a higher (P < 0.05) MPOD than those with an A allele., Conclusions: these results suggest that BCMO1 and CD36 are implicated in plasma and retina concentrations of lutein and that genetic variants in these genes can modulate blood and retina concentrations of lutein.

Vitamin E and carotenoids are fat-soluble micronutrients carried by plasma lipoproteins. Their plasma concentrations are governed by several factors, some of which are genetic, but data on these genetic factors remain scarce. We hypothesized that genes involved in lipid metabolism, i.e. the genes implicated in intestinal uptake, intracellular trafficking, and the lipoprotein distribution of lipids, play a role in the plasma concentrations of these micronutrients. To verify this hypothesis, we assessed whether the plasma status of vitamin E and carotenoids is related to genes involved in lipid metabolism. Fasting plasma vitamin E (alpha- and gamma-tocopherol) and carotenoid (alpha- and beta-carotene, lutein, lycopene, beta-cryptoxanthin, and zeaxanthin) concentrations were measured in 48 males and 80 females. The following genes were genotyped [single nucleotide polymorphisms (SNP)]: apolipoprotein (apo) A-IV, apo B, apo E, lipoprotein lipase, and scavenger-receptor class B type I (SR-BI). Plasma alpha-tocopherol concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV, apo E, and SR-BI. Plasma gamma-tocopherol concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV and SR-BI. Alpha-carotene concentrations were different (P < 0.05) in subjects bearing different SNP in SR-BI. Beta-carotene concentrations were different (P < 0.05) in subjects bearing different SNP in apo B and SR-BI. Lycopene concentrations were different (P < 0.05) in subjects bearing different SNP in apo A-IV and apo B. Beta-cryptoxanthin concentrations were different (P < 0.05) in subjects bearing different SNP in SR-BI. Plasma lutein and zeaxanthin concentrations did not differ in subjects bearing different SNP. Most of the differences remained significant after the plasma micronutrients were adjusted for plasma triglycerides and cholesterol. These results suggest that genes involved in lipid metabolism influence the plasma concentrations of these fat-soluble micronutrients.

Background: Epidemiologic studies link Mediterranean-type diets to a low incidence of cardiovascular disease; however, few dietary intervention studies have been undertaken, especially in primary prevention., Objectives: In the Mediterranean Diet, Cardiovascular Risks and Gene Polymorphisms (Medi-RIVAGE) study, the effects of a Mediterranean-type diet (Med group) or a low-fat diet (low-fat group) on risk factors were evaluated in 212 volunteers (men and women) with moderate risk factors for cardiovascular disease., Design: After the 3-mo dietary intervention, changes in many risk factors were evaluated. Dietary questionnaires and plasma nutritional markers were used to test compliance., Results: Although the dietary goals were only partially reached, changes in dietary habits were observed in both groups (n = 169): protein, carbohydrate, and fiber intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved. BMI, total and triacylglycerol-rich lipoprotein (TRL) cholesterol, triacylglycerols, TRL triacylglycerols, apolipoproteins A-I and B, insulinemia, glycemia, and the homeostasis model assessment score were significantly lower after 3 mo. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI. There was a trend for a diet-by-time interaction for LDL cholesterol (P = 0.09). Our data predicted a 9% reduction in cardiovascular disease risk with the low-fat diet and a 15% reduction with this particular Mediterranean diet., Conclusion: After a 3-mo intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent.