M. Carmen López-Sabater

Premature delivery influences the immunological composition of colostrum and transitional and mature human milk

Human breast milk is the ideal nutrition for the newborn, and in addition to its nutritional contribution, necessary for infant growth and development, it contains various immune bioactive factors that confer some of the numerous beneficial effects of breastfeeding. The current study analyzed the concentrations of IgA, growth factors such as epidermal growth factor (EGF), TGFβ1, and TGFβ2, cytokines IL-6, IL-8, IL-10, IL-13, and TNFα, and TNF-receptor I (TNF-RI) in colostrum and transitional and mature milk from mothers with mature, premature, and very premature infants. Human milk samples were collected from mothers delivering at term (T), preterm (PT), and very preterm (VPT). Milk from all the mothers was collected at 3 different time points after delivery corresponding to colostrum and transitional and mature milk. After obtaining milk whey, IgA, EGF, TGFβ1, and TGFβ2 were determined by ELISA and IL-6, IL-8, IL-10, IL-13, TNFα and TNF-RI by cytometric bead array immunoassay. The colostrum of the PT group was extremely rich in most of the factors studied, but higher concentrations than in the T group were only found for IL-6 (P = 0.051), TGFβ1, and TGFβ2 (P < 0.05). Conversely, the colostrum of the VPT group had lower concentrations of IgA, IL-8, IL-10, and TNFα than those in the T group (P < 0.05). Results suggest that maternal lactogenic compensatory mechanisms accelerating the development of immature breast-fed preterm infants may take effect only after wk 30 of gestation.

Elevated Circulating LDL Phenol Levels in Men Who Consumed Virgin Rather Than Refined Olive Oil Are Associated with Less Oxidation of Plasma LDL

In human LDL, the bioactivity of olive oil phenols is determined by the in vivo disposition of the biological metabolites of these compounds. Here, we examined how the ingestion of 2 similar olive oils affected the content of the metabolic forms of olive oil phenols in LDL in men. The oils differed in phenol concentrations as follows: high (629 mg/L) for virgin olive oil (VOO) and null (0 mg/L) for refined olive oil (ROO). The study population consisted of a subsample from the EUROLIVE study and a randomized controlled, crossover design was used. Intervention periods lasted 3 wk and were preceded by a 2-wk washout period. The levels of LDL hydroxytyrosol monosulfate and homovanillic acid sulfate, but not of tyrosol sulfate, increased after VOO ingestion (P < 0.05), whereas the concentrations of circulating oxidation markers, including oxidized LDL (oxLDL), conjugated dienes, and hydroxy fatty acids, decreased (P < 0.05). The levels of LDL phenols and oxidation markers were not affected by ROO consumption. The relative increase in the 3 LDL phenols was greater when men consumed VOO than when they consumed ROO (P < 0.05), as was the relative decrease in plasma oxLDL (P = 0.001) and hydroxy fatty acids (P < 0.001). Plasma oxLDL concentrations were negatively correlated with the LDL phenol levels (r = -0.296; P = 0.013). Phenols in LDL were not associated with other oxidation markers. In summary, the phenol concentration of olive oil modulates the phenolic metabolite content in LDL after sustained, daily consumption. The inverse relationship of these metabolites with the degree of LDL oxidation supports the in vivo antioxidant role of olive oil phenolics compounds.

Plasma fatty acid composition, estimated desaturase activities, and their relation with the metabolic syndrome in a population at high risk of cardiovascular disease

BACKGROUND & AIMS The metabolic syndrome (MetS) is a clustering of various metabolic abnormalities which is associated with increased risk of cardiovascular disease (CVD) and type 2 diabetes mellitus. Due to its increasing prevalence, it has become an important public health concern. Altered fatty acid (FA) composition and desaturase activities have been associated with several metabolic diseases, including MetS. The aim of the present study was to evaluate the relationship of the plasma FA profile and desaturase activities with the MetS in a Mediterranean population at high risk of CVD. METHODS Baseline data from 427 participants aged 55-80 years who took part in the interventional PREDIMED study were obtained. Individual FA was determined in plasma and desaturase activities were estimated from product/precursor ratios. Odds ratios (OR) and partial correlation coefficients were used to examine these relations with MetS and its components, respectively. RESULTS We found higher levels of C14:0, C16:0, C16:1n-7, estimated Δ(9)- or stearoyl-CoA desaturase (SCD), and estimated Δ(6) desaturase (D6D), and lower levels of C18:2n-6 in people with MetS compared to those without it. After adjustment for several confounders, only higher quartiles of C14:0, C16:0, C16:1n-7, and D6D were found to be associated with an increasing prevalence of MetS, while higher quartiles of C18:2n-6 were inversely associated with MetS. High proportions of C14:0, C16:0, C16:1n-7, C20:3n-6, SCD, and D6D, and decreased proportions of C18:2n-6 and estimated Δ(5)-desaturase (D5D) were associated with adverse profiles of several metabolic risk factors. Women showed more unhealthy FA pattern and lipid profiles than men, but only among those with MetS. CONCLUSION A FA composition and estimated desaturase activities consisting in high levels of SFA, SCD and D6D, and low levels of PUFA and D5D are associated with increased MetS probability and are characteristic of people presenting MetS, especially women. These findings support those observed in non-Mediterranean populations in which an altered FA profile and estimated desaturase activities are associated with MetS.

Breastfeeding, Long-Chain Polyunsaturated Fatty Acids in Colostrum, and Infant Mental Development

BACKGROUND: Breastfeeding has been associated with improved neurodevelopment in children. However, it remains unknown to what extent nutritional advantages of breast milk may explain this relationship. OBJECTIVE: We assessed the role of parental psychosocial factors and colostrum long-chain polyunsaturated fatty acid (LC-PUFA) levels in the relationship between breastfeeding and childrens neurodevelopment. METHODS: A population-based birth cohort was established in the city of Sabadell (Catalonia, Spain) as part of the INMA-INfancia y Medio Ambiente Project. A total of 657 women were recruited during the first trimester of pregnancy. Information about parental characteristics and breastfeeding was obtained by using a questionnaire, and trained psychologists assessed mental and psychomotor development by using the Bayley Scales of Infant Development in 504 children at 14 months of age. RESULTS: A high percentage of breastfeeds among all milk feeds accumulated during the first 14 months was positively related with child mental development (0.37 points per month of full breastfeeding [95% confidence interval: 0.06–0.67]). Maternal education, social class, and intelligence quotient only partly explained this association. Children with a longer duration of breastfeeding also exposed to higher ratios between n-3 and n-6 PUFAs in colostrum had significantly higher mental scores than children with low breastfeeding duration exposed to low levels. CONCLUSIONS: Greater levels of accumulated breastfeeding during the first year of life were related to higher mental development at 14 months, largely independently from a wide range of parental psychosocial factors. LC-PUFA levels seem to play a beneficial role in childrens mental development when breastfeeding levels are high.

Changes in the phenolic content of low density lipoprotein after olive oil consumption in men. A randomized crossover controlled trial.

Olive oil decreases the risk of CVD. This effect may be due to the fatty acid profile of the oil, but it may also be due to its antioxidant content which differs depending on the type of olive oil. In this study, the concentrations of oleic acid and antioxidants (phenolic compounds and vitamin E) in plasma and LDL were compared after consumption of three similar olive oils, but with differences in their phenolic content. Thirty healthy volunteers participated in a placebo-controlled, double-blind, crossover, randomized supplementation trial. Virgin, common, and refined olive oils were administered during three periods of 3 weeks separated by a 2-week washout period. Participants were requested to ingest a daily dose of 25 ml raw olive oil, distributed over the three meals of the day, during intervention periods. All three olive oils caused an increase in plasma and LDL oleic acid (P < 0.05) content. Olive oils rich in phenolic compounds led to an increase in phenolic compounds in LDL (P < 0.005). The concentration of phenolic compounds in LDL was directly correlated with the phenolic concentration in the olive oils. The increase in the phenolic content of LDL could account for the increase of the resistance of LDL to oxidation, and the decrease of the in vivo oxidized LDL, observed in the frame of this trial. Our results support the hypothesis that a daily intake of virgin olive oil promotes protective LDL changes ahead of its oxidation.

Mediterranean Diet Improves High-Density Lipoprotein Function in High-Cardiovascular-Risk IndividualsClinical Perspective: A Randomized Controlled Trial

Background: The biological functions of high-density lipoproteins (HDLs) contribute to explaining the cardioprotective role of the lipoprotein beyond quantitative HDL cholesterol levels. A few small-scale interventions with a single antioxidant have improved some HDL functions. However, to date, no long-term, large-scale, randomized controlled trial has been conducted to assess the effects of an antioxidant-rich dietary pattern (such as a traditional Mediterranean diet [TMD]) on HDL function in humans. Methods: This study was performed in a random subsample of volunteers from the PREDIMED Study (Prevención con Dieta Mediterránea; n=296) after a 1-year intervention. We compared the effects of 2 TMDs, one enriched with virgin olive oil (TMD-VOO; n=100) and the other enriched with nuts (TMD-Nuts; n=100), with respect to a low-fat control diet (n=96). We assessed the effects of both TMDs on the role of HDL particles on reverse cholesterol transport (cholesterol efflux capacity, HDL ability to esterify cholesterol, and cholesteryl ester transfer protein activity), HDL antioxidant properties (paraoxonase-1 arylesterase activity and total HDL antioxidant capacity on low-density lipoproteins), and HDL vasodilatory capacity (HDL ability to induce the release of nitric oxide in endothelial cells). We also studied the effects of a TMD on several HDL quality-related characteristics (HDL particle oxidation, resistance against oxidative modification, main lipid and protein composition, and size distribution). Results: Both TMDs increased cholesterol efflux capacity relative to baseline (P=0.018 and P=0.013 for TMD-VOO and TMD-Nuts, respectively). The TMD-VOO intervention decreased cholesteryl ester transfer protein activity (relative to baseline, P=0.028) and increased HDL ability to esterify cholesterol, paraoxonase-1 arylesterase activity, and HDL vasodilatory capacity (relative to control, P=0.039, P=0.012, and P=0.026, respectively). Adherence to a TMD induced these beneficial changes by improving HDL oxidative status and composition. The 3 diets increased the percentage of large HDL particles (relative to baseline, P<0.001). Conclusions: The TMD, especially when enriched with virgin olive oil, improved HDL atheroprotective functions in humans. Clinical Trial Registration: URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.

Effects of 1-year intervention with a Mediterranean diet on plasma fatty acid composition and metabolic syndrome in a population at high cardiovascular risk.

Background & Aims Metabolic syndrome (MetS) has become an important public concern due to its increasing prevalence. An altered fatty acid composition has been associated with MetS, but the Mediterranean diet has been shown to have a protective effect. The aim of the present study was to analyze the influence of a Mediterranean dietary pattern, as assessed by the biomarkers of food supplied, on the plasma fatty acid composition and its relation with MetS after 1 year of intervention. Methods A total of 424 subjects were randomly selected from the PREDIMED randomized dietary trial after completing a 1-year intervention program. Participants aged 55 to 80 years and at high risk of cardiovascular disease were randomly assigned to three dietary interventions: Mediterranean diet supplemented with virgin olive oil or nuts, or a low-fat diet. Results After 1 year of intervention participants in the virgin olive oil group showed significantly increased plasma concentrations of palmitic and oleic acids, but reduced proportions of margaric, stearic, and linoleic acids. In turn, subjects in the nut group showed significantly increased levels of palmitic, linoleic, and α-linolenic acids, but reduced proportions of myristic, margaric, palmitoleic, and dihommo-γ-linoleic acids. Increases in the biomarkers of foods supplied to the Mediterranean diet groups, i.e., oleic and α-linolenic acids, were beneficially associated with the incidence, reversion and prevalence of MetS. No weight changes were observed among participants. Conclusions The nut and olive oil diets induced a fatty acid composition that has been shown to be beneficial in the face of MetS. Therefore, a Mediterranean diet rich in fats of vegetable origin may be a useful tool for the management of MetS without the need for concerns over weight gain due to its high fat content. Trial Registration Controlled-Trials.com ISRCTN35739639

Ultra-High-Pressure Liquid Chromatographic method for the analysis of tocopherols in human colostrum and milk

A rapid, highly sensitive and direct Ultra-High-Pressure Liquid Chromatographic method was developed and validated for quantifying delta-, beta+gamma-, and alpha-tocopherol in human colostrum and milk. Two reversed-phase chromatographic columns and two detectors (Fluorescence Detector or FD and Photodiode Detector Array or PDA) were used and both methods were independently validated. Two internal standards were selected according to the detector used. Recoveries ranged from 96.71% to 103.55% and the relative standard deviations for the within-day precision were below 6% (PDA) and 3% (FD). Both approaches enabled to achieve low detection limits, on the order of ng (PDA) or pg (FD). Only 300muL of sample and a chromatographic run of less than 1.6min were enough to efficiently quantify the isomers in the colostrum and milk of Spanish women.

Interaction of Olive Oil Phenol Antioxidant Components with Low-density Lipoprotein

Phenolic compounds have shown to inhibit LDL oxidation in vitro and ex vivo; however, they are hydrosoluble compounds while LDL is a lipoprotein. Analysis of phenolic compounds in LDLs by HPLC is necessary to demonstrate their binding capacity to lipoproteins. We developed and validated a solid phase extraction method (SPE) that allowed us the purification of LDL samples and their analysis by HPLC. This methodology allowed us to demonstrate the in vitro binding capacity of tyrosol, one of the main phenolic compounds in olive oil, to LDL. In the intervention dietary study with volunteers, food rich in phenolic compounds affected LDL composition. Changes in LDL phenolics composition are not observed after the short-term ingestion of food rich in phenolic compounds. However, after one week of olive oil consumption and Mediterranean diet there was an increase in phenolics (p=0.021). An accumulative effect seems necessary to observe significative differences in LDL phenolic composition.

Diet quality of a population sample from coastal north-east Spain evaluated by a Mediterranean adaptation of the Diet Quality Index (DQI)

OBJECTIVE To assess the adherence to the Mediterranean dietary pattern in the population from a coastal region from north-east Spain and its relationship to diseases, applying the Mediterranean Diet Quality Index (M-DQI) validated by the use of several biomarkers. DESIGN Cross-sectional nutrition survey. SETTING Population-based random sample derived from the Catalan Nutrition Survey. SUBJECTS A total of 621 healthy adults. RESULTS The Catalan representative sample presented a mean M-DQI score of 6.6 (sd 2.3, median 7, range 0-14). The percentage of adherence to the Mediterranean diet was 53 %; 10 % of subjects showed high adherence to the Mediterranean diet, while only 2 % were categorized as poorest adherence. The plasma fatty acid profile of the Catalan sample progressed with perfect regularity throughout the index ranges. Both EPA and DHA presented a significant correlation to the M-DQI (r = -0.410 for EPA and -0.360 for DHA). A significant increase in palmitic, oleic and alpha-linolenic acids and a significant decrease in stearic, linoleic and arachidonic acids content were also observed. The mean values for the M-DQI according to the clinical characteristics of the Catalan sample were also calculated. CONCLUSIONS The M-DQI has been demonstrated a suitable tool for assessment of an individuals nutritional status according to the Mediterranean dietary pattern and for clinical purposes. Although the current diet followed in Catalonia seems to agree with the main characteristics of the Mediterranean diet, the promotion of the Mediterranean pattern should be reinforced in the Catalan population, especially among young people.