RESUMEN
OBJECTIVES: Vitamin D insufficiency (blood 25-hydroxyvitamin D <50 nmol/L) is a global health problem. Vitamin D food fortification might be a solution, but knowledge is sparse on which food matrices yield the highest bioavailability. The aim of this study was to investigate the influence of different food matrices including complex formations with whey proteins on the human bioavailability of vitamin D. METHODS: In this randomized, multiple crossover trial, we enrolled 30 postmenopausal women 60 to 80 y of age with vitamin D insufficiency. We measured changes in serum concentrations of vitamin D3 (D3) postprandially for 24 h in response to the intake of 500 mL of different food matrices with 200 µg D3 added compared with a control (500 mL of water). Foods included apple juice with whey protein isolate (WPI), apple juice, semi-skim milk, and water (with D3). The food matrices were provided in a randomized order with ≥10-d washout period between them. On each intervention day, blood samples were collected at 0, 2, 4, 6, 8, 10, 12 and 24 h. RESULTS: D3 with WPI in juice did not enhance area under the curve (AUC) of serum D3 compared with juice without WPI (370 nmol × 24 h/L; 95% confidence interval [CI], 321-419 versus 357 nmol × 24 h/L; 95% CI, 308-406 nmol × 24 h/L; P = 0.65). However, compared with juice, the AUC was significantly higher in response to the intake of D3 in milk (452 nmol × 24 h/L; 95% CI, 402-502 nmol × 24 h/L) and water with D3 (479 nmol × 24 h/L; 95% CI, 430-527 nmol × 24 h/L; P < 0.05). No difference was observed between milk and water (P = 0.34). CONCLUSIONS: The bioavailability of D3 was superior in milk and water compared with juice, regardless of whether WPI was added.
Asunto(s)
Colecalciferol , Deficiencia de Vitamina D , Humanos , Femenino , Disponibilidad Biológica , Estudios Cruzados , Posmenopausia , Alimentos Fortificados , Vitamina D , Vitaminas , Suplementos Dietéticos , Método Doble CiegoRESUMEN
Vitamin D deficiency is a global health issue with consequences for bone health. Complexation of vitamin D3 with specific whey proteins might increase the bioavailability and enhance the effect of dietary supplementation on health outcomes. The current rat study was set up to investigate if complexation of vitamin D3 with whey protein isolate (WPI) or ß-lactoglobulin (B-LG) increases bioavailability of the vitamin and how it impacts markers of bone turnover and bone structure. For 8 weeks, growing male Sprague Dawley rats (n = 48) were fed a vitamin D-deficient diet and during the final 4 weeks gavage dosing of vitamin D3 either alone (VitD) or complexed with WPI (VitD + WPI) or ß-LG (VitD + B-LG) was administered. A placebo treatment (placebo) was also included. After sacrifice, samples of bone were collected and analyzed using biomechanical testing and µCT scanning. The concentrations of vitamin D3, vitamin D3 metabolites and bone markers (P1NP and CTX) were measured in serum. The results showed that VitD + B-LG appeared to induce lower levels of 25-hydroxy vitamin D3 in serum compared to VitD alone. Markers of bone turnover were generally higher in the VitD group compared to placebo and the VitD + WPI and VitD + B-LG treatments. No effects of treatments on bone strength or bone microstructure were detected. In conclusion, whey protein complexation of vitamin D3 supplements appeared to have no beneficial effects on circulating vitamin D3 metabolites but this did not impose changes in bone strength or trabecular bone microstructure.
Asunto(s)
Colecalciferol , Deficiencia de Vitamina D , Animales , Biomarcadores , Suplementos Dietéticos , Masculino , Ratas , Ratas Sprague-Dawley , Vitamina D , Deficiencia de Vitamina D/tratamiento farmacológico , Vitaminas/uso terapéutico , Proteína de Suero de Leche/uso terapéuticoRESUMEN
The angiopoietin-like 4 (ANGPLT4) protein is involved in lipid metabolism and is known to inhibit lipoprotein lipase in the bloodstream. We investigated the effect of milk on intestinal ANGPTL4 and the metabolic profile of growing pigs and the effect of free fatty acids (FFAs) on ANGPTL4 in ex vivo and in vitro assays. Feeding pigs whole milk increased intestinal ANGPTL4 mRNA and increased fecal excretion of long-chain FFA compared to the control group fed soybean oil (n = 9). Furthermore, FFAs (C4-C8) induced ANGPTL4 gene expression in porcine intestinal tissue mounted in Ussing chambers and ANGPTL4 protein secretion to both the apical and basolateral sides of intestinal Caco-2 cells on permeable membranes. Altogether, these results support an ANGPTL4-induced secretion of fecal FFAs. Urinary levels of FFAs (C4-C12), 3-hydroxyadipic acid, and suberic acid were also increased by milk consumption, indicating higher energy expenditure compared to the control group.
Asunto(s)
Angiopoyetinas/metabolismo , Ácidos Grasos/farmacocinética , Heces/química , Mucosa Intestinal/metabolismo , Leche , Proteína 4 Similar a la Angiopoyetina , Angiopoyetinas/genética , Animales , Células CACO-2 , Dieta , Ácidos Grasos/metabolismo , Ácidos Grasos/orina , Femenino , Regulación de la Expresión Génica , Humanos , Aceite de Soja/farmacología , Sus scrofaRESUMEN
BACKGROUND: Abdominal obesity and exaggerated postprandial lipemia are independent risk factors for cardiovascular disease (CVD) and mortality, and both are affected by dietary behavior. OBJECTIVE: We investigated whether dietary supplementation with whey protein and medium-chain saturated fatty acids (MC-SFAs) improved postprandial lipid metabolism in humans with abdominal obesity. DESIGN: We conducted a 12-wk, randomized, double-blinded, diet intervention study. Sixty-three adults were randomly allocated to one of 4 diets in a 2 × 2 factorial design. Participants consumed 60 g milk protein (whey or casein) and 63 g milk fat (with high or low MC-SFA content) daily. Before and after the intervention, a high-fat meal test was performed. We measured changes from baseline in fasting and postprandial triacylglycerol, apolipoprotein B-48 (apoB-48; reflecting chylomicrons of intestinal origin), free fatty acids (FFAs), insulin, glucose, glucagon, glucagon-like peptide 1 (GLP-1), and gastric inhibitory polypeptide (GIP). Furthermore, changes in the expression of adipose tissue genes involved in lipid metabolism were investigated. Two-factor ANOVA was used to examine the difference between protein types and fatty acid compositions, as well as any interaction between the two. RESULTS: Fifty-two participants completed the study. We found that the postprandial apoB-48 response decreased significantly after whey compared with casein (P = 0.025) independently of fatty acid composition. Furthermore, supplementation with casein resulted in a significant increase in the postprandial GLP-1 response compared with whey (P = 0.003). We found no difference in postprandial triacylglycerol, FFA, insulin, glucose, glucagon, or GIP related to protein type or MC-SFA content. We observed no interaction between milk protein and milk fat on postprandial lipemia. CONCLUSION: We found that a whey protein supplement decreased the postprandial chylomicron response compared with casein in persons with abdominal obesity, thereby indicating a beneficial impact on CVD risk. This trial was registered at clinicaltrials.gov as NCT01472666.
Asunto(s)
Productos Lácteos , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Hiperlipidemias/dietoterapia , Metabolismo de los Lípidos , Obesidad Abdominal/dietoterapia , Adulto , Anciano , Apolipoproteína B-48/sangre , Glucemia/metabolismo , Caseínas/administración & dosificación , Quilomicrones/sangre , Suplementos Dietéticos , Método Doble Ciego , Ácidos Grasos no Esterificados/sangre , Femenino , Polipéptido Inhibidor Gástrico/sangre , Glucagón/sangre , Péptido 1 Similar al Glucagón/sangre , Humanos , Insulina/sangre , Masculino , Comidas , Persona de Mediana Edad , Proteínas de la Leche/administración & dosificación , Evaluación Nutricional , Periodo Posprandial , Triglicéridos/sangre , Proteína de Suero de LecheRESUMEN
The present work aimed to investigate the milk oxidative stability when the sheep diet includes a source of polyphenols (grape seed, (GS)) and a source of polyunsaturated fatty acids (linseed, (LIN)), alone or in combination (MIX) compared to a control group (CON). For this purpose light-induced oxidation in milk was studied. After 24 h of light exposure the lipid hydroperoxides increased in milk in the LIN and MIX groups. The calculated ratio between the level of lipid hydroperoxides and unsaturated fatty acids (UFAs) in milk was lower in the GS and MIX than in the LIN group. At the same time the level of the ratio between hexanal/linoleic acid in milk was lower in the GS and MIX than in the CON group. Although the dietary inclusion of grape seed did not reduce the level of lipid oxidation products in sheep milk, it effectively reduced the extent of oxidation of UFA.
Asunto(s)
Alimentación Animal/análisis , Lino/metabolismo , Lípidos/química , Leche/química , Semillas/metabolismo , Vitis/metabolismo , Animales , Suplementos Dietéticos/análisis , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/metabolismo , Femenino , Luz , Leche/metabolismo , Leche/efectos de la radiación , Oxidación-Reducción/efectos de la radiación , OvinosRESUMEN
Whey fat has a relatively high level of unsaturated fatty acids, and as such, whey products with a high fat content are vulnerable to oxidation. The purposes of the present study were to assess the oxidative development in whey fat concentrate (WFC) during production and investigate the effect of the addition of antioxidants. Green tea extract (GTE) or a mixture of ascorbyl palmitate and tocopherol (AP/TOC) were used, each in two concentrations. Samples were taken before and after pasteurization of WFC and after drying. The level of volatile oxidation products decreased during processing, while dityrosine concentrations increased during drying. GTE reduced oxidation in both unpasteurized and pasteurized WFC, while the effect of AP/TOC was nonsignificant. In the WFC powder, there was no significant effect of the antioxidants. In conclusion, results indicated that GTE was able to inhibit oxidation in WFC during production and that AP/TOC addition had no effect.