An Integrative Approach of an In Vitro Measurement of the Digestibility of Triacylglycerols of Human Milk.

Several studies have been published regarding the effect of different factors on the digestion of milk lipids, considering their natural structural arrangement as milk fat globules and the efficiency of the digestive enzymes in the lipolysis of such complex structures. During digestion, the lipolytic products are dispersed in vesicles and micelles, which are the source for absorption of digested lipids. Therefore, it is necessary to consider the isolation of the micellar phase from the digesta to appropriately determine the amounts and classes of lipids which are bioaccessible. This study presents an integrative approach that included an isolation procedure to separate the micellar fraction from undigested and non-micellar parts, and the distribution of digested milk lipids in micelles determined directly through chromatographic techniques. Four groups of five full term mothers donated colostrum or mature milk. Two sets of samples were analyzed directly (raw), and two sets were pasteurized and then analyzed. Our data revealed that the profile of digested milk lipids is different depending on the lactation period and processing stage, while the carbon atom number distribution of the digested triacylglycerols in the micellar fraction provides a substantial information regarding the acylglycerols species that are less available for absorption.

Effect of gestational age (preterm or full term) on lipid composition of the milk fat globule and its membrane in human colostrum.

Human colostrum is the first milk secreted by the mother after birth and constitutes the ideal food for the newborn, because its chemical composition, rich in immunoglobulins, antimicrobial peptides, growth factors, bioactive lipids, and other important molecules, is perfectly adapted to the metabolic, digestive, and immunological immaturity of the newborn. An incomplete gestational period can affect the maturity of the mammary gland and its ability to secrete milk with the proper composition for the newborn's condition. Previous studies indicate that the mammary gland modulates the profiles of bioactive lipids present in the different phases of lactation from colostrum to mature milk. Given the key role played by the polar lipids (PL) (phospho- and sphingolipids) of the milk fat globule membrane (MFGM) in the immune system and cognitive development of the newborn, it is crucial to analyze whether the content and distribution of the PL are affected by gestation period. Therefore, this study aimed to determine the milk fat globule (MFG) and MFGM lipid compositions of human colostrum samples from 20 healthy preterm and full-term mothers. Lipid characterization using chromatographic techniques (gas chromatograph mass spectrometry and HPLC-evaporative light-scattering detection) revealed differences related to length of gestation in the profiles of lipid classes and fatty acid and triacylglyceride contents of colostrum. This comparative analysis leads to noteworthy outcomes about the changing roles of the PL, considering the preterm or full-term condition. We found a lack of correlation of some PL (such as phosphatidylcholine, phosphatidylinositol, and phosphatidylserine) with the delivery term; these could be denoted as structural category lipids. However, sphingomyelin and phosphatidyl-ethanolamine exhibited trends to decrease in full-term colostrum, indicating that in the final stage of pregnancy specific accretion of some PL occurs, which should be denoted as a nutritional redistribution.

In Vitro Digestion of Human Milk: Influence of the Lactation Stage on the Micellar Carotenoids Content.

Human milk is a complex fluid with nutritive and non-nutritive functions specifically structured to cover the needs of the newborn. The present study started with the study of carotenoid composition during progress of lactation (colostrum, collected at 3-5 d postpartum; mature milk, collected at 30 d postpartum) with samples donated from full-term lactating mothers (women with no chronic diseases, nonsmokers on a regular diet without supplements, n = 30). Subsequently, we applied an in vitro protocol to determine the micellarization efficiency of the carotenoids, which were separated by HPLC and quantified by the external standard method. That in vitro protocol is tailored for the biochemistry of the digestive tract of a newborn. To the best of our knowledge, the present study is the first report of carotenoids micellar contents, obtained in vitro. This study reveals, from the in vitro perspective, that colostrum and mature milk produce significant micellar contents of carotenoids despite lipids in milk are within highly complex structures. Indeed, the lactation period develops some influence on the micellarization efficiency, influence that might be attributed to the dynamics of the milk fat globule membrane (MFGM) during the progress of lactation.

Carotenoid Content in Human Colostrum is Associated to Preterm/Full-Term Birth Condition.

Factors such as lactation stage and premature and small-for-gestational conditions could lead to great inter-individual variability in the carotenoid content of human milk. The aim was to analyze the carotenoid content in colostrum and mature milk of preterm (PT) and full-term (FT) mothers to establish whether they are significantly different and, if so, the stage of lactation when the differences are established. Samples of blood, colostrum, and mature milk were collected from Spanish donating mothers who gave birth to PT or FT infants. Carotenoids from serum and milk samples were analyzed by HPLC-atmospheric pressure chemical ionization (APCI)-MS. Quantitatively, colostrum from PT mothers presented lower total carotenoid content when compared to that from FT mothers. The only exception was lutein, where levels were not different. The transition from colostrum to mature milk makes observed differences in the carotenoid content disappear, since there were no variances between PT and FT groups for both individual and total carotenoid content. The premature birth condition affects the quantitative carotenoid composition of the colostrum but has no effect on the lutein content. This fact could be related to the significant role of this xanthophyll in the development of infant retina and feasibly to cognitive function.

Xanthophyll esters are found in human colostrum.

SCOPE: Carotenoids in human milk are associated with other lipid counterparts in several metabolic processes. One interesting association that has not been demonstrated to date is the presence of xanthophyll esters. Colostrum and mature milk samples were analyzed to determine the occurrence of xanthophyll esters and identify the compounds. Thus, the association of the amounts of these compounds with lactation and whether they are significant contributors to the carotenoid profile of human milk was assessed. METHODS AND RESULTS: Pre-term and term delivering mothers were included in the study to donate colostrum at 3-5 days postpartum and mature milk at 15 days postpartum. Carotenoids extracts were subjected to a clean-up procedure to remove the triacylglycerol fraction and then analyzed by HPLC-MSn . Identification of xanthophyll esters was achieved by considering their chromatographic behaviour, UV-visible characteristics and MSn features. CONCLUSION: Xanthophyll esters are significant contributors to the carotenoid profile in the colostrum, while mature milk does not contain these compounds. Therefore, fatty acid acylation to xanthophylls is activated during the accumulation of carotenoids in the human mammary gland. The sharp decline in the amount of xanthophyll esters in mature milk indicates that the lipophilic components are those recently incorporated in the mammary epithelium.

Adaptación de las recomendaciones internacionales en estabilización y reanimación neonatal 2015 / Changes in the international recommendations on neonatal stabilisation and resuscitation (2015)

Las recomendaciones internacionales del International Liaison Committee on Resuscitation (ILCOR), mediante una revisión exhaustiva de la evidencia disponible en el desarrollo de las medidas de soporte a la transición y de reanimación del recién nacido tras su nacimiento, aportan una guía universal a partir de la cual cada grupo o comité local puede adaptarla a su realidad e idiosincrasia, y elaborar sus propias guías o recomendaciones. El objetivo de esta revisión es analizar los principales cambios, abordar las controversias generadas desde 2010, contrastarlas con las de otras organizaciones nacionales e internacionales como son la European Resuscitation Council (ERC), American Heart Association (AHA) o la Australian-New Zealand Committee on Resuscitation (ANZCOR). De esta forma, el Grupo de Reanimación Neonatal de la Sociedad Española de Neonatología (GRN-SENeo) consensúa respuestas claras sobre muchas de las preguntas que ofrecen diferentes opciones de actuación, y genera las próximas recomendaciones de nuestro país para el soporte a la transición o la reanimación del recién nacido tras su nacimiento, con seguridad y eficacia

The International Liaison Committee on Resuscitation (ILCOR) recommendations provide a universal guide of measures to support the transition and resuscitation of newborn after their birth. This guide is expected to be adapted by local groups or committees on resuscitation, according to their own circumstances. The objective of this review is to analyse the main changes, to discuss several of the controversies that have appeared since 2010, and contrasting with other national and international organisations, such as European Resuscitation Council (ERC), American Heart Association (AHA), or the Australian-New Zealand Committee on Resuscitation (ANZCOR). Thus, the Neonatal Resuscitation Group of the Spanish Society of Neonatology (GRN-SENeo) aims to give clear answers to many of the questions when different options are available, generating the forthcoming recommendations of our country to support the transition and/or resuscitation of a newborn after birth, safely and effectively

[Changes in the international recommendations on neonatal stabilisation and resuscitation (2015)]. / Adaptación de las recomendaciones internacionales en estabilización y reanimación neonatal 2015.

The International Liaison Committee on Resuscitation (ILCOR) recommendations provide a universal guide of measures to support the transition and resuscitation of newborn after their birth. This guide is expected to be adapted by local groups or committees on resuscitation, according to their own circumstances. The objective of this review is to analyse the main changes, to discuss several of the controversies that have appeared since 2010, and contrasting with other national and international organisations, such as European Resuscitation Council (ERC), American Heart Association (AHA), or the Australian-New Zealand Committee on Resuscitation (ANZCOR). Thus, the Neonatal Resuscitation Group of the Spanish Society of Neonatology (GRN-SENeo) aims to give clear answers to many of the questions when different options are available, generating the forthcoming recommendations of our country to support the transition and/or resuscitation of a newborn after birth, safely and effectively.