Fiber in enteral nutrition: why and what for? / La fibra en la nutrición enteral: ¿por qué y para qué?

Enteral formulas containing fiber, designed to be administered orally or by gavage, have been used for decades. Although their indication in the pediatric population does not have a global consensus, knowledge about the benefits of using fiber to promote healthier microbiota has grown in recent years. Different fiber types' physicochemical characteristics (solubility, viscosity, fermentability) determine their functions. The impact of fiber use on preventing specific chronic pathologies (cardiovascular disease, cancer, diabetes) has been reported in epidemiological studies. In controlled studies, changes in stool consistency, intestinal transit, and the composition and function of the microbiota have been observed since fiber produces fermentation metabolites such as short-chain fatty acids, which improve metabolic and immunological aspects. Different pediatric pathologies could benefit from the use of fiber.

Las fórmulas enterales que contienen fibra, diseñadas para ser administradas de forma oral o por sonda, han sido utilizadas durante décadas. Si bien su indicación en población pediátrica no cuenta con un consenso global, el conocimiento sobre los beneficios de la utilización de fibra en relación con el intestino, para promover una microbiota más saludable, ha crecido en los últimos años. Los diferentes tipos de fibra tienen características fisicoquímicas (solubilidad, viscosidad, fermentabilidad) que determinan sus funciones. El impacto del uso de fibra sobre la prevención de ciertas patologías crónicas (enfermedad cardiovascular, cáncer, diabetes) ha sido reportado en estudios epidemiológicos. En estudios controlados, se han observado cambios en la consistencia de las heces, en el tránsito intestinal y en la composición y función de la microbiota, ya que la fibra produce metabolitos de fermentación tales como ácidos grasos de cadena corta, lo cual mejora aspectos metabólicos e inmunológicos. Diferentes patologías pediátricas podrían verse beneficiadas por el uso de fibra.

Escenarios lácteos y microbiota intestinal en los primeros 1000 días / Milk scenarios and gut microbiota in the first 1000 days of life

La leche humana es el estándar de oro para la nutrición del bebé y debe iniciarse en la primera hora de vida. La leche de vaca, de otros mamíferos o las bebidas vegetales no se deben ofrecer antes del año de vida. Sin embargo, algunos niños requieren, al menos en parte, de fórmulas infantiles. Aun con las sucesivas mejoras a lo largo de la historia mediante la incorporación de oliogosacáridos, probióticos, prebióticos, sinbióticos y postbióticos, las fórmulas infantiles siguen siendo perfectibles para reducir la brecha de salud entre los bebés amamantados y aquellos alimentados con fórmula. En este sentido, se espera que la complejidad de las fórmulas siga aumentando a medida que se conozca mejor cómo modular el desarrollo de la microbiota intestinal. El objetivo de este trabajo fue realizar una revisión no sistemática del efecto de los diferentes escenarios lácteos sobre la microbiota intestinal.

Human milk is the gold standard for infant nutrition, and breastfeeding should be started within the first hour of life. Cow's milk, other mammalian milk, or plant-based beverages should not be offered before 1 year of age. However, some infants require, at least in part, infant formulas. Even with subsequent enhancements throughout history, with the addition of oligosaccharides, probiotics, prebiotics, synbiotics, and postbiotics, infant formulas still have room for improvement in reducing the health gap between breastfed and formula-fed infants. In this regard, the complexity of infant formulas is expected to continue to increase as the knowledge of how to modulate the development of the gut microbiota is better understood. The objective of this study was to perform a non-systematic review of the effect of different milk scenarios on the gut microbiota.

Microbiota intestinal y cólicos infantiles: ¿hay lugar para los prebióticos, probióticos y posbióticos? / Gut Microbiota and Infant Colic: is there a Place for Prebiotics, Probiotics, and Postbiotics?

El consumo de probióticos, prebióticos y posbióticos, o su combinación, puede contribuir a mantener una microbiota intestinal saludable ya que permite la regulación de su disbiosis en el caso de algunas enfermedades o trastornos, principalmente en los trastornos gastrointestinales funcionales (TGIF). El microbioma intestinal es protagonista esencial en la fisiopatología de los TGIF a través de sus funciones metabólicas y nutricionales, el mantenimiento de la integridad de la mucosa intestinal y la regulación de la respuesta inmunitaria. Las investigaciones realizadas hasta la fecha indican que los probióticos, prebióticos y posbióticos pueden tener efectos inmunomoduladores directos y clínicamente relevantes. Existen pruebas del uso de esta familia de bióticos en individuos sanos para mejorar la salud general y aliviar los síntomas en una serie de enfermedades como los cólicos infantiles. La colonización y establecimiento de la microbiota comienza en el momento del nacimiento; los primeros 2-3 años de vida son fundamentales para el desarrollo de una comunidad microbiana abundante y diversa. Diversos estudios científicos realizados mediante técnicas tradicionales dependientes de cultivo y más recientemente por técnicas moleculares han observado diferencias en las poblaciones bacterianas de bebés sanos y aquellos que sufren TGIF, estos últimos caracterizados por un aumento de especies patógenas y una menor población de bifidobacterias y lactobacilos, en comparación con los primeros. En tal contexto, se considera que la microbiota intestinal como protagonista en el desarrollo de esos trastornos, entre ellos los cólicos infantiles, a través de sus funciones metabólicas, nutricionales, de mantenimiento de la integridad de la mucosa intestinal y regulación de la respuesta inmunitaria. Esto ha abierto la puerta al estudio de la utilización de prebióticos, probióticos y posbióticos en el tratamiento y/o prevención de los TGIF infantiles. El parto vaginal y de término así como la lactancia son fundamentales en la constitución de una microbiota saludable. Como herramientas de apoyo, existen estudios de eficacia que sustentan la administración de esta familia de bióticos, principalmente en los casos en que la lactancia no sea posible o esté limitada. (AU)

The consumption of probiotics, prebiotics, and postbiotics, or a combination of them, can contribute to maintaining a healthy intestinal microbiota as it allows the regulation of its dysbiosis in the case of some diseases or disorders, mainly in functional gastrointestinal disorders (FGIDs). The gut microbiome is an essential player in the pathophysiology of FGIDs through its metabolic and nutritional functions, the maintenance of intestinal mucosal integrity, and the regulation of the immune response. Research results thus far indicate that probiotics, prebiotics, and postbiotics may have direct and clinically relevant immunomodulatory effects. There is evidence regarding the prescription of this family of biotics in healthy individuals to improve overall health and alleviate symptoms in many conditions like infantile colic. The colonization and microbiota establishment begins at birth; the first 2-3 years of life are critical for developing an abundant and diverse microbial community. Several scientific studies performed by traditional culture-dependent techniques and more recently by molecular techniques have observed differences in the bacterial populations of healthy infants and those suffering from FGIDs, the latter characterized by an increase in pathogenic species and a lower population of bifidobacteria and lactobacilli, compared to the former. In this context, the intestinal microbiota plays a leading role in the onset of these disorders, including infantile colic, through its metabolic and nutritional functions, maintenance of the integrity of the intestinal mucosa, and regulation of the immune response. That has opened the door to the study of prebiotics, probiotics, and postbiotics usage in the treatment and or prevention of infantile FGIDs. Vaginal and term delivery and breastfeeding are fundamental in the constitution of a healthy microbiota. As supportive tools, there are efficacy studies that support the administration of this family of biotics, mainly in cases where lactation is not possible or is limited.

Inmunomodulación con bióticos y alergia alimentaria en pediatría / Immunomodulation properties of biotics and food allergy in pediatrics

El parto prematuro, la cesárea, el uso de antibióticos y la lactancia materna limitada son señalados como responsables en parte del aumento de enfermedades crónicas no transmisibles en niños, como las alergias, principalmente la alergia a la proteína de la leche de vaca (APLV). Quienes desarrollan enfermedades alérgicas muestran diferencias en la composición de su microbiota intestinal durante los primeros meses de vida, en comparación con los que no lo hacen. Las intervenciones tempranas para modular la microbiota intestinal y el sistema inmunológico pueden ser herramientas claves para el abordaje y tratamiento de la APLV. El criterio clínico y el trabajo interdisciplinario de alergólogos, gastroenterólogos, inmunólogos, microbiólogos y nutricionistas le permitirá al pediatra lograr un adecuado diagnóstico y un tratamiento oportuno. En este contexto, el empleo de bióticos (prebióticos, probióticos, sinbióticos y posbióticos) como herramientas nutricionales complementarias tiene un presente con sustento científico y un futuro promisorio para la prevención y tratamiento de estas patologías.

Preterm birth, C-section, antibiotic use, and limited breastfeeding are blamed in part for the increasing incidence of chronic noncommunicable diseases among children, such as allergies, mainly cow's milk protein allergy (CMPA). Those who develop allergic diseases, against those who do not, show differences in the composition of their gut microbiota during the first months of life. Early interventions to modulate the intestinal microbiota and the immune system may be the key tools for the management of CMPA. Clinical judgment and the interdisciplinary work of allergists, gastroenterologists, immunologists, microbiologists, and nutritionists will allow pediatricians to achieve an adequate diagnosis and a timely treatment. In this setting, the use of biotics (prebiotics, probiotics, synbiotics, and postbiotics) as supplementary dietary tools is scientifically supported at present and seems to be very promising for the prevention and treatment of these conditions.

Alergia a la proteína de la leche de vaca; nuevos conocimientos desde una visión multidisciplinaria / Cow's milk protein allergy; new knowledge from a multidisciplinary perspective

En las últimas décadas, se ha observado una mayor prevalencia, persistencia y gravedad de la alergia a la proteína de leche de vaca (APLV). Se han postulado diversas hipótesis respecto a posibles mecanismos responsables, con énfasis en el papel de la microbiota en la inducción y el mantenimiento de la tolerancia inmunitaria, así como la importancia del establecimiento temprano de una microbiota saludable a través de la promoción de la lactancia materna, el parto por vía vaginal, el uso racional de antibióticos e inhibidores de la bomba de protones, junto con la introducción temprana y variada de alimentos. La utilización de probióticos y la inmunoterapia específica para alérgenos (ITA) emergen como las estrategias terapéuticas con más evidencia a favor para la adquisición de tolerancia. El objetivo de esta revisión ha sido describir la información actual respecto a los mecanismos inmunitarios involucrados en la APLV, el papel de la microbiota y las perspectivas futuras en el tratamiento.

In recent decades, a higher prevalence, persistence, and severity of cow's milk protein allergy (CMPA) have been observed. Different hypotheses have been proposed in relation to potential responsible mechanisms, with emphasis on the role of the microbiota in the induction and maintenance of immune tolerance as well as the importance of establishing a healthy microbiota in an early manner through the promotion of breastfeeding, vaginal delivery, rational use of antibiotics and proton pump inhibitors, along with an early introduction of varied foods. The use of probiotics and allergenspecific immunotherapy (AIT) come up as the treatment strategies with the greatest evidence in favor of tolerance acquisition. The objective of this review was to describe the information currently available about the immune mechanisms involved in CMPA, the role of microbiota, and future treatment perspectives.

Functional Microbes and Their Incorporation into Foods and Food Supplements: Probiotics and Postbiotics.

Life expectancy has dramatically increased over the past 200 years, but modern life factors such as environmental exposure, antibiotic overuse, C-section deliveries, limited breast-feeding, and diets poor in fibers and microbes could be associated with the rise of noncommunicable diseases such as overweight, obesity, diabetes, food allergies, and colorectal cancer as well as other conditions such as mental disorders. Microbial interventions that range from transplanting a whole undefined microbial community from a healthy gut to an ill one, e.g., so-called fecal microbiota transplantation or vaginal seeding, to the administration of selected well-characterized microbes, either live (probiotics) or not (postbiotics), with efficacy demonstrated in clinical trials, may be effective tools to treat or prevent acute and chronic diseases that humans still face, enhancing the quality of life.

Intolerancia a la lactosa: mitos y verdades. Actualización / Lactose intolerance: myths and facts. An update

La lactosa es el principal carbohidrato de la leche materna. Es un disacárido conformado por glucosa y galactosa. Su producción en la glándula mamaria es independiente de la dieta materna. Además de proveer energía, es la única fuente de galactosa de la dieta, necesaria para la síntesis de macromoléculas como oligosacáridos, glicoproteínas y glicolípidos. Favorece la absorción y retención de calcio, magnesio y cinc. Su digestión por la enzima lactasa y posterior absorción tienen lugar en intestino delgado. El déficit de lactasa, que puede ser primario congénito (muy infrecuente), primario tardío o secundario por lesión intestinal, puede generar intolerancia con síntomas como dolor, distensión abdominal, flatulencia y diarrea. En el colon, bifidobacterias y lactobacilos pueden hidrolizarla. El manejo nutricional de la intolerancia deberá hacerse siempre preservando la lactancia materna. La reducción o suspensión de la lactosa deberá ser transitoria y se reemplazarán alimentos suspendidos por otros con adecuados aportes calóricos, proteicos y de minerales y vitaminas.

Lactose is the main carbohydrate present in humanmilk. It is a disaccharide made up of glucoseand galactose. It is produced in the mammaryglands, regardless of maternal diet. In addition toproviding energy, it is the only source of dietarygalactose, necessary for macromolecule synthesis,including oligosaccharides, glycoproteins, andglycolipids. It favors calcium, magnesium, andzinc absorption and retention. Its digestion bylactase and subsequent absorption occurs inthe small intestine. Lactase deficiency may beclassified into congenital primary (very rare),late-onset primary or secondary due to an injuryof the intestine; it may cause intolerance withpain, abdominal distension, abdominal gas, anddiarrhea. In the colon, it may be hydrolyzed bybifidobacteria and lactobacilli. The nutritionalmanagement of intolerance should alwayspreserve breastfeeding. Lactose reduction orelimination should be transient, and eliminatedfood should be replaced with other similar incalorie, protein, mineral, and vitamin content.

Abordaje de los probióticos en pediatría: el rol de Lactobacillus rhamnosus GG / Approach to probiotics in pediatrics: the role of Lactobacillus rhamnosus GG

El parto prematuro, las cesáreas, los antibióticos y la lactancia materna limitada contribuyen al aumento de enfermedades crónicas no transmisibles. El objetivo fue realizar una revisión descriptiva del uso de probióticos en pediatría, con foco en la cepa Lactobacillus rhamnosus GG. Ciertos probióticos han demostrado ser eficaces en la diarrea aguda y en la diarrea asociada a antibióticos. L. rhamnosus GG y Saccharomyces boulardii pueden acortar la duración y los síntomas. L. reuteri DSM 17938 y L. rhamnosus GG fueron efectivos para el abordaje del cólico del lactante. El uso de esta cepa en fórmulas infantiles para alergia a las proteínas de leche de vaca promovería la adquisición más temprana de tolerancia. En la prevención de dermatitis atópica, la administración de L. rhamnosus GG durante el embarazo redujo su manifestación en el bebé. El empleo de probióticos como coadyuvantes es una posibilidad para considerar en la práctica pediátrica actual.

Preterm birth, C-sections, antibiotics, and limited breastfeeding contribute to the increase in noncommunicable diseases. Our objective was to perform a descriptive review of probiotic use in pediatrics, focused on Lactobacillus rhamnosus GG. Certain probiotics have demonstrated to be effective in acute diarrhea and antibiotic-associated diarrhea. L. rhamnosus GG and Saccharomyces boulardii may shorten their duration and symptoms. L. reuteri DSM 17938 and L. rhamnosus GG were effective to manage infant colic. The use of this strain in infant formulas for cow's milk protein allergy may promote an earlier tolerance acquisition. In relation to the prevention of atopic dermatitis, the administration of L. rhamnosus GG during pregnancy reduced its development in the infant. The use of probiotics as adjuvants is a possibility to consider in current pediatric practice.

Harinas de lupino blanco (Lupinus albus) y andino (L. mutabilis) aptas para consumo: características físico-químicas y funcionales / White lupine (Lupinus albus) and Andean lupine (L. mutabilis) flours suitable for consumption: physico-chemical and functional characteristics

Resumen Introducción: los lupinos son legumbres fuente de nutrientes y fitoquímicos con propiedades beneficiosas para la salud. Sin embargo, presentan alcaloides que deben ser eliminados previos al consumo. El objetivo del estudio fue obtener y caracterizar harinas de lupino blanco y andino, aptas para el consumo. Materiales y método: los granos se desamargaron por método acuoso tradicional que incluyó remojo por 18 horas, cocción por 1 hora y lavado por 5 días. Luego, se secaron en estufa, se molieron y tamizaron. Se determinó alcaloides, proteínas, grasas, fibra dietaria total, sodio, fósforo, color, índice de absorción y solubilidad en agua, polifenoles totales, flavonoides, carotenoides y perfil de fenoles en semillas crudas y harinas tratadas. Resultados: el contenido de alcaloides en las harinas tratadas se encontró entre los límites establecidos para la ingesta segura (<0,07 g/100g). Las proteínas se encontraron entre 25-39 g/100g, grasas entre 12-23 g/100g, fibra dietaria total 35-50 g/100g y cenizas 1,5-3,3 g/100g. El calcio se encontró entre 210-323 mg/100g, fósforo 140-202 mg/100g y sodio 38-44 mg/100g. El color correspondió al amarillo con tendencia al rojo. La harina de lupino andino tratada presentó mayor índice de absorción de agua (7,8 g/g) y solubilidad en agua (78,8%). Los productos tratados presentaron polifenoles (13,4 y 20,8 mg/100g), flavonoides (27,5 y 8,7 mg/100g) y carotenoides (0,3 y 0,9 mg/100g). El perfil de fenoles correspondió a 3 flavonas y 3 isoflavonas en lupino blanco. En el lupino andino, se detectaron 5 flavonas y 3 isoflavonas. Conclusiones. Las harinas tratadas presentan características físico-químicas y funcionales que podrían representar ingredientes alternativos a las tradicionales como trigo y soja, para la formulación de alimentos saludables.

Abstract Introduction: lupins are legumes that are a source of nutrients and phytochemicals with beneficial properties for health. However, they present alkaloids that must be eliminated prior to consumption. The objective of the work was to obtain and characterize White and Andean lupine flours suitable for consumption. Materials and method: the grains were debittered using traditional aqueous method that included soaking for 18 hours, cooking for 1 hour and washing for 5 days. Then, they were dried in an oven, ground and sieved. Alkaloids, proteins, fats, total dietary fiber, sodium, phosphorus, color, absorption rate and water solubility, total polyphenols, flavonoids, carotenoids and phenol profile in raw seeds and treated flours were determined. Results: the alkaloid contents of treated flours were within the limits established for safe intake (less than 0.07 g/100g). Proteins were found between 25-39 g/100g, fats between 12-23 g/100g, total dietary fiber 35-50 g/100g and ash 1.5-3.3 g/100g. Calcium was found between 210-323 mg/100g, phosphorus 140-202 mg/100g and sodium 38-44 mg/100g. The color corresponded to yellow with a tendency to red. The treated Andean lupine flour presented a higher rate of water absorption (7.8 g/g) and solubility in water (78.8%). The treated products presented polyphenols (13.4 and 20.8 mg/100g), flavonoids (27.5 and 8.7 mg/100g) and carotenoids (0.3 and 0.9 mg/100g). The phenolic profile corresponded to 3 flavones and 3 isoflavones in white lupine. In Andean lupine, 5 flavones and 3 isoflavones were detected. Conclusion: the treated flours could represent alternative ingredients to the traditional ones such as wheat and soy for the formulation of healthy foods.

Alimentos fermentados y probióticos en niños. La importancia de conocer sus diferencias microbiológicas / Fermented foods and probiotics for children. The importance of knowing their microbiological differences

La leche materna provee microorganismos que colonizan el intestino y programan el sistema inmunológico para desarrollar tolerancia oral. Entre los 6 meses de lactancia materna exclusiva y los 2 años de lactancia prolongada recomendada, la alimentación complementaria conlleva una reducción progresiva en el ingreso de microorganismos vivos al ecosistema intestinal. Esto se debe a que los alimentos en general -a diferencia de la leche materna- o se encuentran desprovistos de microorganismos o, si los poseen, suelen inactivarse durante la cocción. Los alimentos fermentados y los probióticos podrían constituir una estrategia nutricional valiosa, dado que garantizarían la provisión de microorganismos vivos ante la reducción o interrupción anticipada de la lactancia. Los términos "alimentos fermentados" y "probióticos" no son sinónimos. La identidad microbiológica, la inocuidad y la existencia de estudios clínicos de eficacia para unos y otros son claves para entender sus diferencias y decidir una eventual recomendación alimentaria

Breast milk provides microorganisms that colonize the gut and program the immune system to develop oral tolerance. Between the 6 months of exclusive breastfeeding and the recommended 2 years of prolonged breastfeeding, complementary feeding leads to a progressive reduction in the entry of live microorganisms into the gut ecosystem. This is because foods in general -unlike breast milk- are devoid of microorganisms or, if present, they are often inactivated during cooking. Fermented foods and probiotics could be a valuable nutritional strategy, as they would ensure the supply of live microorganisms in the face of a reduction or early cessation of breastfeeding. The terms "fermented foods" and "probiotics" are not synonymous. Microbiological identity, safety, and the existence of clinical efficacy studies supporting both are key to understand their differences and decide on an eventual dietary recommendation

Ecosistema intestinal en la infancia: rol de los "bióticos" / Gut ecosystem during infancy: The role of "biotics"

En los últimos años, las evidencias han demostrado la importancia de la microbiota intestinal en la salud del individuo. La dinámica de la colonización temprana y el establecimiento de una comunidad abundante y diversa de microorganismos saludables, a partir de un parto vaginal y lactancia materna, resultan fundamentales en la conformación de una matriz inmunológica saludable. Esta revisión tiene como objetivo describir las evidencias disponibles sobre el desarrollo de la microbiota en el primer año de vida y el actual potencial que ofrece el uso de prebióticos, probióticos, simbióticos y posbióticos durante esta etapa esencial de la vida

In recent years, the evidence has demonstrated the relevance of the gut microbiota in an individual's health. The dynamics of an early colonization and the establishment of a community of plenty, diverse, and healthy microorganisms from a vaginal delivery and breastfeeding are critical for the development of a healthy immune matrix. The objective of this review is to describe the available evidence on microbiota development in the first year of life and the current possibilities offered by prebiotics, probiotics, symbiotics, and postbiotics during such critical stage of life.

Síndrome urémico hemolítico y yogur: entre la creencia popular y la evidencia científica / Hemolytic uremic syndrome and yoghurt: popular belief and scientific evidence

Algunos profesionales de la salud desaconsejan el consumo del yogur por el riesgo de provocar Síndrome Urémico Hemolítico, una enfermedad grave causada por cepas de E. coli productor de toxina Shiga (STEC por sus siglas en inglés). Estas bacterias pueden pasar del intestino del ganado vacuno a la carne o a la leche en condiciones inadecuadas de trabajo en frigoríficos o establecimientos productores de leche, respectivamente, siendo las hamburguesas insuficientemente cocidas el principal vector de la enfermedad y la leche cruda sin pasteurizar o los productos lácteos elaborados con ésta, otro factor de riesgo. En la industria láctea, el yogur se elabora con leche que es sometida a un doble tratamiento térmico. En la bibliografía moderna reportes de la presencia de STEC en yogures industriales, y los trabajos de revisión y meta-análisis no incluyen al yogur, pero sí a la leche sin pasteurizar, como vectores de trasmisión de STEC. En este contexto, y dada la evidencia científica disponible actualmente en relación a E. coli productor de toxina Shiga, el SUH y el yogur, parecería que estamos ante la presencia de una correlación espuria, la asociación de dos hechos que no tienen relación causal entre sí, más que a un hecho científico del cual uno (el yogur) es el responsable del otro (SUH).

Some health professionals discourage yogurt because of the risk of Hemolytic Uremic Syndrome (HUS), a serious disease caused by strains of Shiga toxin-producing E. coli (STEC). These bacteria can pass from the intestine of cattle to meat or milk under inadequate working conditions in slaughterhouses or milking plants. Undercooked hamburgers the main is vector of disease and unpasteurized raw milk or dairy products made with it, are another risk factors. In the dairy industry, yoghurt is made from milk that undergoes a double heat treatment. There are no reports of the presence of STEC in industrial yogurts in the modern bibliography, and reviews and meta-analysis do not point to yogurt as a risk factor for STEC, but rather unpasteurized milk. In this context, and given the scientific evidence currently available regarding STEC, HUS and yogurt, it would seem that we are in the presence of a spurious correlation, the association between two facts that have no causal relationship between them, rather than a scientific fact for which one (yogurt) may be responsible for the other (HUS).

Biodisponibilidad de minerales que lados y no que lados: una revisión sistemática / Bioavailability of chelated and non-chelated minerals: a systematic review

RESUMEN Los minerales son elementos esenciales para la vida y su equilibrio es imprescindible para múltiples procesos fisiológicos, bioquímicos y metabólicos. La forma en que son ingeridos determina su funcionalidad. Se sugiere que los minerales quelados tienen mejor biodisponibilidad. El objetivo del trabajo fue realizar una revisión sistemática para verificar si los minerales quelados (MQ) son más biodisponibles que los no quelados (MNQ). Se revisaron publicaciones en el período entre 2007 y 2017 en las bases de datos Pubmed, Lilacs y Cochrane Library en los idiomas portugués e inglés, y con las palabras clave: "mineral chelates", "micronutrient chelate", "bioavailability micronutrient chelate", organic mineral, "iron chelate", "zinc chelate", "magnesium chelate", "copper chelate" y "chelate" y sus respectivas traducciones en portugués (idioma original de este artículo). Se seleccionaron 446 artículos, quedando 24 trabajos pendientes de aplicación de criterios de inclusión/exclusión, siendo 15 de ellos en animales (manganeso, zinc, cobre, hierro, cromo, cobalto y selenio) y 9 en humanos, sólo con hierro y calcio. Los estudios demostraron mayor absorción, transporte y biodisponibilidad para los MQ en comparación con los MNQ. Sin embargo, serían necesarios más estudios en humanos, abordando la biodisponibilidad de otros minerales, así como la estandarización de las dosificaciones de estos micronutrientes.

ABSTRACT Minerals are essential elements for life and their balance is important for multiple physiological, biochemical and metabolic processes. The way they are ingested determines their functionality. It has been suggested that chelated minerals have better bioavailability. The objective of this work was to perform a systematic review of published articles to verify if chelated minerals are more bioavailable than non-chelated minerals. Publications were reviewed in the period between 2007 and 2017 in Pubmed, Lilacs and Cochrane Library databases in Portuguese and English with the keywords: "mineral chelates", "micronutrient chelate", "bioavailability micronutrient chelate", organic mineral, "iron chelate", "zinc chelate", "magnesium chelate", "copper chelate" and "chelate" and their respective translations in Portuguese (the original language of this article). 446 articles were selected and 24 papers were left after the application of inclusion / exclusion criteria. Of these, 15 were in animals (manganese, zinc, copper, iron, chromium, cobalt and selenium) and 9 in humans, and focused on iron and calcium. The studies showed greater absorption, transport and bioavailability for chelated compared to non-chelated minerals. More human studies, however, are necessary to address the bioavailability of other minerals, as well as the standardization of the dosajes of these micronutrients.

The immunopotentiating effects of shark-derived protein hydrolysate.

OBJECTIVE: Peptides derived from natural sources can act as immunomodulating agents and prevent infections. The aim of this study was to investigate the immunopotentiating and protective effects of a shark-derived protein hydrolysate (SPH) against an enterotoxigenic Escherichia coli H10407 infection in a murine model. METHODS: Mice were fed an aqueous solution of SPH for 7 days before being inoculated with an experimental enterotoxigenic Escherichia coli H10407 infection. After euthanasia, small intestines were removed for histological study and the number of IgA and IgG producing cells was determined by direct immunofluorescence. Cytokines were measured in the serum and the intestinal fluid. RESULTS: The oral administration of SPH enhanced the gut barrier function via up-regulation of immunoglobulin A-producing cells and intestinal cytokines production, including interleukin-6 and tumor necrosis factor-α. The increase of transforming growth factor-ß and interleukin-10 contribute to the down-regulation of uncontrolled-inflammatory reaction induced by E. coli infection. From these results, the anti-inflammatory properties of SPH may be caused by regulation and priming mechanisms of the immune system. CONCLUSION: Enzymatic protein degradation confers immunomodulating and protective potentials to shark proteins and the resulted peptides could be used as an alternative therapy to reduce the risk of bacterial infections and inflammatory-related diseases.

Milk fermentation products of L. helveticus R389 activate calcineurin as a signal to promote gut mucosal immunity.

BACKGROUND: Fermented milks containing probiotic bacteria are a way of delivering bioactive constituents to targets in the gastrointestinal tract. We reported previously that the fermentation of milk at constant pH 6 by L. helveticus R389 increased its content of peptide fractions, and the oral administration of the non-bacterial fraction (FMSpH6) to mice increased total secretory IgA in the intestinal lumen and enhanced the number of IgA and various cytokines producing cells as well as the secretion of IL-6 by small intestine epithelial cells. We also demonstrated that this FMSpH6 was effective for the prevention of Salmonella typhimurium infection in mice. In this work, we studied in mice the impact of the oral administration of the supernatant of milk fermented by L. helveticus R389 on the gut physiology by measuring parameters such as calcium channels and E-cadherin expression, the activation of the biological signal calcineurin and mast and goblet cells, as a way to determine some mechanisms involved in the immunomodulating effects of the milk fermentation products, observed in previous studies. We analyzed the impact of the supernatant of milk fermented by L. helveticus R389 at pH6-controlled on the expression of calcineurin and on the reinforcement of the ephitelial barrier, measuring parameters such as calcium channels and E-cadherin expression and in the reinforcement of the non-specific immunity determining mast cells and goblet cells associated to the gut. RESULTS: We observed an enhanced expression of TRPV6 channels in the duodenum, indicating an improved capacity for dietary Ca2+ uptake. We demonstrated an enhanced expression of calcineurin in the small intestine, able to upregulate immune parameters such as IL-2 and TNF production, with an increase in the number of these cytokines secreting cells. We determined an increase in the number of mucosal mast cells and goblet cells, which would mean an improved state of mucosal surveillance at sites of infection. CONCLUSION: The oral administration of the supernatant of milk fermented by L. helveticus R389 enhanced the gut mucosal immunity by improving the mechanisms that reinforce the epithelial and non-specific barriers and the gut functioning at sites of infection, with an improvement in the expression of the enzyme calcineurin, an important signal in the network that activates the gut immune system. The results of this work contribute to revealing the mechanisms underlying the immunomodulation of the gut immune function by fermented milks with probiotic bacteria.

Effects of the oral administration of the products derived from milk fermentation by kefir microflora on immune stimulation.

Nutritional status has a major impact on the immune system. Probiotic effects ascribed to fermented dairy products arise not only from whole microorganisms but also from metabolites (peptides, exopolysaccharides) produced during the fermentation. We recently demonstrated the immunomodulating capacity of kefir in a murine model. We now aimed at studying the immunomodulating capacity in vivo of the products derived from milk fermentation by kefir microflora (PMFKM) on the gut. BALB/c mice received the PMFKM for 2, 5 or 7 consecutive days. IgA+ and IgG+ cells were determined on histological slices of the small and large intestine. IL-4, IL-6, IL-10, IL-12, IFNgamma and TNFalpha were determined in the gut, intestinal fluid and blood serum. IL-6 was also determined in the supernatant of a primary culture of small intestine epithelial cells challenged with PMFKM. PMFKM up-regulated IL-6 secretion, necessary for B-cell terminal differentiation to IgA secreting cells in the gut lamina propria. There was an increase in the number of IgA+ cells in the small and large intestine. The increase in the number of IgA+ cells was accompanied by an increase in the number of IL-4+, IL-10+ and IL-6+ cells in the small intestine. Effects of PMFKM in the large intestine were less widely apparent than the ones observed at the small intestine lamina propria. All cytokines that increased in the small intestine lamina propria, also did so in blood serum, reflecting here the immunostimulation achieved in the gut mucosa. We observed that the PMFKM induced a mucosal response and it was able to up and down regulate it for protective immunity, maintaining the intestinal homeostasis, enhancing the IgA production at both the small and large intestine level. The opportunity exists then to manipulate the constituents of the lumen of the intestine through dietary means, thereby enhancing the health status of the host.

Effects of kefir fractions on innate immunity.

Innate immunity that protects against pathogens in the tissues and circulation is the first line of defense in the immune reaction, where macrophages have a critical role in directing the fate of the infection. We recently demonstrated that kefir modulates the immune response in mice, increasing the number of IgA+ cells in the intestinal and bronchial mucosa and the phagocytic activity of peritoneal and pulmonary macrophages. The aim of this study was to further characterize the immunomodulating capacity of the two fractions of kefir (F1: solids including bacteria and F2: liquid supernatant), by studying the cytokines produced by cells from the innate immune system: peritoneal macrophages and the adherent cells from Peyer's patches. BALB/c mice were fed either kefir solid fraction (F1) or kefir supernatant (F2) for 2, 5 or 7 consecutive days. The number of cytokine (IL-1alpha, IFNgamma, TNFalpha, IL-6 and IL-10) producing cells was determined on peritoneal macrophages and adherent cells from Peyer's patches. Both kefir fractions (F1 and F2) induced similar cytokine profiles on peritoneal macrophages (only TNFalpha and IL-6 were up-regulated). All cytokines studied on adherent cells from Peyer's patches were enhanced after F1 and F2 feeding, except for IFNgamma after F2 administration. Moreover, the percentage of IL-10+cells induced by fraction F2 on adherent cells from Peyer's patches was significantly higher than the one induced by fraction F1. Different components of kefir have an in vivo role as oral biotherapeutic substances capable of stimulating immune cells of the innate immune system, to down-regulate the Th2 immune phenotype or to promote cell-mediated immune responses against tumours and also against intracellular pathogenic infections.

Effects of the oral administration of the exopolysaccharide produced by Lactobacillus kefiranofaciens on the gut mucosal immunity.

The probiotic effects ascribed to lactic acid bacteria (LAB) and their fermented dairy products arise not only from whole microorganisms and cell wall components but also from peptides and extracellular polysaccharides (exopolysaccharides) produced during the fermentation of milk. There is a lack of knowledge concerning the immune mechanisms induced by exopolysaccharides produced by lactic acid bacteria, which would allow a better understanding of the functional effects described to them. The aim of this study was to investigate the in vivo immunomodulating capacity of the exopolysaccharide produced by Lactobacillus kefiranofaciens by analyzing the profile of cytokines and immunoglobulins induced at the intestinal mucosa level, in the intestinal fluid and blood serum. BALB/c mice received the exopolysaccharide produced by L. kefiranofaciens for 2, 5 or 7 consecutive days. At the end of each period of administration, control and treated mice were sacrificed and the numbers of IgA+ and IgG+ cells were determined on histological slices of the small and large intestine by immunofluorescence. Cytokines (IL-4, IL-6, IL-10, IL-12, IFNgamma and TNFalpha) were also determined in the gut lamina propria as well as in the intestinal fluid and blood serum. There was an increase of IgA+ cells in the small and large intestine lamina propria, without change in the number of IgG+ cells in the small intestine. This study reports the effects of the oral administration of the exopolysaccharide produced by L. kefiranofaciens in the number of IgA+ cells in the small and large intestine, comparing simultaneously the production of cytokines by cells of the lamina propria and in the intestinal fluid and blood serum. The increase in the number of IgA+ cells was not simultaneously accompanied by an enhance of the number of IL-4+ cells in the small intestine. This finding would be in accordance with the fact that, in general, polysaccharide antigens elicit a T-independent immune response. For IL-10+, IL-6+ and IL-12+ cells, the values found were slightly increased compared to control values, while IFNgamma+ and TNFalpha+ cells did not change compared to control values. The effects observed on immunoglobulins and in all the cytokines assayed in the large intestine after kefiran administration were of greater magnitude than the ones observed in the small intestine lamina propria, which may be due to the saccharolytic action of the colonic microflora. In the intestinal fluid, only IL-4 and IL-12 increased compared to control values. In blood serum, all the cytokines assayed followed a pattern of production quite similar to the one found for them in the small intestine lamina propria. We observed that the exopolysaccharide induced a gut mucosal response and it was able to up and down regulate it for protective immunity, maintaining intestinal homeostasis, enhancing the IgA production at both the small and large intestine level and influencing the systemic immunity through the cytokines released to the circulating blood.

Role of intestinal epithelial cells in immune effects mediated by gram-positive probiotic bacteria: involvement of toll-like receptors.

The mechanisms by which probiotic bacteria exert their effects on the immune system are not completely understood, but the epithelium may be a crucial player in the orchestration of the effects induced. In a previous work, we observed that some orally administered strains of lactic acid bacteria (LAB) increased the number of immunoglobulin A (IgA)-producing cells in the small intestine without a concomitant increase in the CD4(+) T-cell population, indicating that some LAB strains induce clonal expansion only of B cells triggered to produce IgA. The present work aimed to study the cytokines induced by the interaction of probiotic LAB with murine intestinal epithelial cells (IEC) in healthy animals. We focused our investigation mainly on the secretion of interleukin 6 (IL-6) necessary for the clonal expansion of B cells previously observed with probiotic bacteria. The role of Toll-like receptors (TLRs) in such interaction was also addressed. The cytokines released by primary cultures of IEC in animals fed with Lactobacillus casei CRL 431 or Lactobacillus helveticus R389 were determined. Cytokines were also determined in the supernatants of primary cultures of IEC of unfed animals challenged with different concentrations of viable or nonviable lactobacilli and Escherichia coli, previously blocked or not with anti-TLR2 and anti-TLR4. We concluded that the small intestine is the place where a major distinction would occur between probiotic LAB and pathogens. This distinction comprises the type of cytokines released and the magnitude of the response, cutting across the line that separates IL-6 necessary for B-cell differentiation, which was the case with probiotic lactobacilli, from inflammatory levels of IL-6 for pathogens.