Leche materna deslactosada con la enzima beta galactosidasa para lactantes intolerantes / Leite materno sem lactose com a enzima beta-galactosidase para lactentes intolerantes / Lactose-free breast milk with the enzyme beta galactosidase for intolerant infants

Introducción: los bebés deben beneficiarse de la leche materna, incluso cuando presentan intolerancia a la lactosa. Por esto, se debe recurrir a la obtención de leche materna deslactosada. Objetivo: analizar el efecto de la enzima beta galactosidasa en la hidrólisis de la lactosa de leche materna madura para bebés clínicamente diagnosticados con intolerancia a la lactosa. Materiales y método: estudio exploratorio, descriptivo y explicativo. El contenido de lactosa se cuantificó desde el inicio hasta el final del tratamiento, controlando temperatura, tiempos y cantidad de enzima ß-galactosidasa adicionada en la leche materna. Se recolectaron 1000 ml de leche materna, obtenidos del Banco de Leche del Hospital General de Medellín (Antioquia, Colombia). Resultados: las muestras donadas se encontraban pasteurizadas y posteriormente fueron sometidas a la acción de la enzima lactasa. Se cuantificó el contenido de lactosa sin la enzima, reportando en promedio 6,34 mg/100 ml ± 0,23. El mayor aporte de lactosa obtenido posterior a la exposición a la enzima (30 minutos) fue de 6,07 mg/ml ± 0,35 (correspondiente a 95 % del contenido inicial), finalizando con un aporte de 0,35 % a una concentración de 0,4 % tras 24 horas, porcentaje que representa 95 % de la hidrólisis total en la leche materna. Conclusiones: en todas las muestras analizadas de diferentes madres se pudo obtener leche materna con bajas concentraciones de lactosa tras 24 horas de haber sido sometidas a la acción de ß-galactosidasa. Lo anterior se establece como una alternativa para los bebés intolerantes a la lactosa, que permitiría no privarlos de todos los beneficios que ofrece este alimento.

Introduction: Babies should benefit from breast milk, even when they are lactose intolerant. For this reason, parents should resort to obtaining lactose-free breast milk. Objective: To examine the effect of the enzyme ß-galactosidase on the hydrolysis of lactose in mature breast milk for babies clinically diagnosed with lactose intolerance. Materials and method: Exploratory, descriptive, and explanatory study. The lactose content was quantified from the beginning to the end of the treatment, controlling variables such as temperature, times, and the amount of ß-galactosidase enzyme added in breast milk. A total of 1000 ml of breast milk were obtained from the milk bank at Hospital General de Medellín (Antioquia, Colombia). Results: Donated samples were first pasteurized and subsequently subjected to the action of the enzyme lactase. The lactose content without the enzyme was quantified, reporting an average of 6.34 mg/100 mL±0.23. The highest contribution of lactose obtained after exposure to the enzyme was 6.07 mg/mL±0.35 (corresponding to 95% of the initial content), at 30 minutes, ending with a contribution of 0.35% at a concentration of 0.4% in 24 hours, percentage that represents 95% of total hydrolysis in breast milk. Conclusions: In all the examined samples from different mothers, it was possible to obtain breast milk with low concentrations of lactose 24 hours after these were exposed to the action of ß-galactosidase. This becomes an alternative for feeding lactose intolerant babies and not deprive them from all the benefits offered by breast milk.

Introdução: os bebês se devem beneficiar do leite materno, mesmo quando tenham intolerância à lactose, razão pela qual se deve recorrer à obtenção de leite materno sem lactose. Objetivo: analisar o efeito da enzima beta-galactosidase na hidrólise da lactose no leite materno maduro para bebês diagnosticados clinicamente com intolerância à lactose. Materiais e método: estudo exploratório, descritivo, explicativo. O teor de lactose foi quantificado do início ao fim do tratamento; temperatura, tempos e quantidade de enzima beta-galactosidase adicionada no leite materno foram controlados; foram coletados 1000ml de leite materno, obtidos no Banco de Leite do Hospital General de Medellín (Antioquia, Colômbia). VResultados: as amostras doadas foram pasteurizadas e posteriormente submetidas à ação da enzima lactase. O teor de lactose sem a enzima foi quantificado, relatando uma média de 6,34mg/100ml±0,23. A maior contribuição de lactose obtida após a exposição à enzima foi de 6,07mg/ml±0,35 (correspondendo a 95% do conteúdo inicial) em 30 minutos, finalizando com uma contribuição de 0,35% na concentração de 0,4% em 24 horas, percentual que representa 95% da hidrólise total no leite materno. Conclusões: em todas as amostras analisadas de diferentes mães, foi possível obter leite materno com baixas concentrações de lactose 24 horas após ser submetido à ação da beta galactosidase, como alternativa para bebês intolerantes à lactose e não os privar de todos os outros benefícios oferecidos por esse alimento ideal.

A restrição de alimentos lácteos é obrigatória para pacientes com doença inflamatória intestinal? Estudo transversal multinacional / Is dairy foods restriction mandatory for inflammatory bowel disease patients: a multinational cross-sectional study

ABSTRACT Background: The role of dairy foods in inflammatory bowel disease (IBD) has been controversial and it is debatable if patients with IBD should avoid milk and dairy products or not, as well as the relationship between these foods and symptoms among those population. Objective: This multi centric cross-sectional study designed to evaluate if it is really necessary to deprive IBD patients from consumption of dairy foods. Methods: A multicenter study with 12 gastroenterology referral centers in four countries was designed to evaluate gastrointestinal (GI) symptoms after consumption of dairy foods from all outpatients with IBD during 6 months and to compare patients treated at the same centers without IBD (non IBD cases). Results: Overall 1888 cases included (872 IBD patients and 1016 non IBD cases). 56.6% of participants were female with average age of 40.1 years. Racially 79.8% participants were Caucasians and originally they were citizens of 10 countries. Relative prevalence of IBD was higher in Africans and Indians and the most frequent prevalence of dairy foods intolerance was seen in Asians. Among IBD patients, 571 cases diagnosed as ulcerative colitis and 189 participants as Crohn's disease. Average duration of diagnosis as IBD was 6.8 years (from 2 months to 35 years). The most prevalent GI symptoms after consumption of all the dairy foods were bloating and abdominal pain. Totally, intolerance of dairy foods and lactase deficiency was more prevalent among IBD patients in comparison with non IBD cases (65.5% vs 46.1%, P=0.0001). But the rate of GI complains among IBD patients who had not any family history of lactase deficiency, history of food sensitivity or both were 59.91%, 52.87% & 50.33% respectively and similar to non IBD cases (P=0.68, 0.98 & 0.99 respectively). Conclusion: The rate of dairy foods intolerance among IBD patients without family history of lactase deficiency or history of food sensitivity is similar to non IBD cases and probably there is no reason to deprive them from this important source of dietary calcium, vitamin D and other nutrients.

RESUMO Contexto: O papel dos alimentos lácteos na doença inflamatória intestinal (DII) tem sido controverso e é discutível se os pacientes com DII devem ou não evitar leite e laticínios, bem como a relação entre esses alimentos e sintomas nesta população. Objetivo: Estudo transversal multicêntrico foi projetado para avaliar se é realmente necessário privar os pacientes com DII do consumo desta classe de alimentos. Métodos: Um estudo multicêntrico com 12 centros de referência em gastroenterologia de quatro países foi projetado para avaliar sintomas gastrointestinais após o consumo de alimentos lácteos em todos os ambulatórios de DII durante seis meses e comparar pacientes tratados nos mesmos centros sem DII. Resultados: No total, foram incluídos 1888 casos (872 pacientes com DII e 1016 casos sem DII. 56,6% dos participantes eram do sexo feminino com idade média de 40,1 anos. 79,8% dos participantes eram caucasianos e originalmente eram cidadãos de 10 países. A prevalência relativa de DII foi maior em africanos e indianos e a prevalência mais frequente de intolerância a alimentos lácteos observada nos asiáticos. Entre os pacientes com DII, 571 casos foram diagnosticados como colite ulcerativa e 189 participantes como doença de Crohn. A duração média do diagnóstico como DII foi de 6,8 anos (de 2 meses a 35 anos). Os sintomas de gastrointestinais mais prevalentes após o consumo de todos os alimentos lácteos foram inchaço e dor abdominal. No total, a intolerância aos alimentos lácteos e a deficiência de lactase foi mais prevalente entre os pacientes com DII em comparação com os casos sem DII (65,5% vs 46,1%, P=0,0001). A taxa de queixas gastrointestinais entre os pacientes com DII que não tinham histórico familiar de deficiência de lactase, histórico de sensibilidade alimentar ou ambos foram de 59,91%, 52,87% e 50,33% respectivamente e semelhantes aos casos sem DII (P=0,68, 0,98 e 0,99, respectivamente). Conclusão: A taxa de intolerância de alimentos lácteos entre pacientes com DII sem histórico familiar de deficiência de lactase ou histórico de sensibilidade alimentar é semelhante aos casos sem DII e provavelmente não há razão para privá-los dessa importante fonte de cálcio dietético, vitamina D e outros nutrientes.

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.

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

Lactose is the main carbohydrate present in human milk. It is a disaccharide made up of glucose and galactose. It is produced in the mammary glands, regardless of maternal diet. In addition to providing energy, it is the only source of dietary galactose, necessary for macromolecule synthesis, including oligosaccharides, glycoproteins, and glycolipids. It favors calcium, magnesium, and zinc absorption and retention. Its digestion by lactase and subsequent absorption occurs in the small intestine. Lactase deficiency may be classified into congenital primary (very rare), late-onset primary or secondary due to an injury of the intestine; it may cause intolerance with pain, abdominal distension, abdominal gas, and diarrhea. In the colon, it may be hydrolyzed by bifidobacteria and lactobacilli. The nutritional management of intolerance should always preserve breastfeeding. Lactose reduction or elimination should be transient, and eliminated food should be replaced with other similar in calorie, protein, mineral, and vitamin content.

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.

One-step purification of a recombinant beta-galactosidase using magnetic cellulose as a support: Rapid immobilization and high thermal stability.

For the first time, this work reported the one-step purification and targeted immobilization process of a ß-galactosidase (Gal) with the Cellulose Binding Domain (CBD) tag, by binding it to different magnetic cellulose supports. The process efficiency after ß-galactosidase-CBD immobilization on magnetic cellulose-based supports showed values of approximately 90% for all evaluated enzymatic loads. Compared with free Gal, derivatives showed affinity values between ß-galactosidase and the substrate 1.2 × higher in the lactose hydrolysis of milk. ß-Galactosidase-CBD's oriented immobilization process on supports increased the thermal stability of the immobilized enzyme by up to 7 × . After 15 cycles of reuse, both enzyme preparations showed a relative hydrolysis percentage of 50% of lactose in milk. The oriented immobilization process developed for purifying recombinant proteins containing the CBD tag enabled the execution of both steps simultaneously and quickly and the obtention of ß-galactosidases with promising catalytic characteristics for application in the food and pharmaceutical industries.

Improvement in Lactose Tolerance in Hypolactasic Subjects Consuming Ice Creams with High or Low Concentrations of Bifidobacterium bifidum 900791.

Although Bifidobacterium bifidum expresses lactase activity, no clinical trials have determined its impact on lactose-intolerant subjects. This study evaluated whether acute and chronic ingestion of ice creams containing B. bifidum 900791 at high (107 CFU/g) or low (105 CFU/g) concentrations improved lactose tolerance in hypolactasic subjects. Fifty subjects were selected based on a positive lactose (20 g) hydrogen breath test (HBT0) and the presence of digestive symptoms. The recruited subjects were required to perform breath tests after the acute ingestion of: (1) ice cream containing 20 g of lactose without a probiotic (HBT1); (2) the same ice cream, accompanied by a lactase tablet (HBT2); (3) the same ice cream containing the low or high dose of probiotic (HBT3-LD and HBT3-HD); and (4) after the chronic consumption of the ice cream without (placebo) or with the low concentration of probiotic for 1 month (HBT4). Significant decreases in H2 excretion during HBT2 and HBT3-HD as well as digestive symptoms during HBT2, HBT3-HD and HBT3-LD were observed compared to HBT0 and HBT1, while the orocecal transit time increased. Chronic consumption of the probiotic ice cream did not enhance lactose tolerance compared to the placebo. These results suggest that the acute ingestion of ice cream containing high or low concentrations of B. bifidum 900791 improves lactose tolerance in hypolactasic subjects.

Production of ß-galactosidase by Trichoderma sp. through solid-state fermentation targeting the recovery of galactooligosaccharides from whey cheese.

AIMS: Optimization of ß-galactosidase production by Trichoderma sp. under solid-state fermentation using wheat bran as solid substrate through an experimental design and its application targeting the recovery of galactooligosaccharides (GOS) from whey cheese. METHODS AND RESULTS: The ß-galactosidase production by Trichoderma sp. increased 2·3-fold (2·67 U g-1 of substrate) culturing the fungus at 30°C for 187 h, at an inoculum of 105 spores per ml, and a 1 : 1·65 (w/v) ratio of wheat bran to tap water. The best enzyme activity was obtained at 55°C and pH 4·5. The catalytic activity was maintained for up to 180 min incubating at 35-45°C, and above 50% at acidic or alkaline pH for up to 24 h. It also presented resistance to chemical compounds. ß-galactosidase catalysed the hydrolysis of the lactose and the transgalactosylation reaction leading to the production of GOS. CONCLUSION: Trichoderma sp. produced ß-galactosidase with transgalactosylation activity that may be used to recover GOS, products with high added value, from whey cheese. SIGNIFICANCE AND IMPACT OF THE STUDY: ß-galactosidases are used in different industrial sectors. Therefore, the Trichoderma ß-galactosidase is a promising alternative for the production of GOS as prebiotic from the dairy effluents, contributing to the reduction in the environmental impact.

Lactose hydrolysis using ß-galactosidase from Kluyveromyces lactis immobilized with sodium alginate for potential industrial applications.

The present study aimed to evaluate the lactose hydrolysis conditions from "coalho" cheese whey using ß-galactosidase (ß-gal) produced by Kluyveromyces lactis immobilized with sodium alginate. Three sodium alginate-based immobilization systems were evaluated (0.5, 0.7, and 1% w/v) for maximizing the immobilization yield (Y), efficiency (EM), and recovered activity (ar). The lactose hydrolysis capacity of the immobilized form of ß-gal was determined, and simulated environments were used to assess the preservation of the immobilized enzyme in the gastrointestinal tract. The results showed that ß-gal immobilization with 1% (w/v) sodium alginate presented the best results (EM of 66%, Y of 41%, and ar of 65%). The immobilization system maintained the highest pH stability in the range between 5.0 and 7.0, with the highest relative activity obtained under pH 5 conditions. The temperature stability was also favored by immobilization at 50 °C for 30 min was obtained a relative activity of 180.0 ± 1.37%. In 6 h, the immobilized ß-gal was able to hydrolyze 46% of the initial lactose content. For the gastrointestinal simulations, around 40% of the activity was preserved after 2 h. Overall, the results described here are promising for the industrial applications of ß-galactosidase from K. lactis.

The importance of lactose intolerance in individuals with gastrointestinal symptoms. / Importancia de la intolerancia a la lactosa en individuos con síntomas gastrointestinales.

Lactose intolerance is a condition with an elevated prevalence worldwide, especially in Latin American, Asian, and African countries. The aim of the present narrative review was to highlight the importance of accurately diagnosing lactose intolerance to prevent self-diagnosis that results in the unnecessary elimination of milk and dairy products from the diet and the consequent deprivation of nutrients that could be essential at certain stages of life. The pathophysiologic mechanism of deficient lactose absorption in the intestine can be primary, secondary to other enteropathies, or coexistent with other intestinal diseases with similar symptoms, such as irritable bowel syndrome, bacterial overgrowth syndrome, or celiac disease, causing confusion in relation to diagnosis and treatment. Lactose intolerance consists of a set of symptoms attributed to the consumption of milk and dairy products that are assumed to be due to deficient digestion of that disaccharide. A wide range of tests have been validated to detect deficient digestion that include blood tests, genetic mutation analyses, breath tests, and recently, a urine test, all of which are described in the present article. Nevertheless, there are few validated questionnaires for symptom evaluation and measurement, partly due to the heterogeneity of concepts and the subjectivity of each of the symptoms.

The Importance of Lactose in the Human Diet: Outcomes of a Mexican Consensus Meeting.

Lactose is a unique component of breast milk, many infant formulas and dairy products, and is widely used in pharmaceutical products. In spite of that, its role in human nutrition or lactose intolerance is generally not well-understood. For that reason, a 2-day-long lactose consensus meeting with health care professionals was organized in Mexico to come to a set of statements for which consensus could be gathered. Topics ranging from lactase expression to potential health benefits of lactose were introduced by experts, and that was followed by a discussion on concept statements. Interestingly, lactose does not seem to induce a neurological reward response when consumed. Although lactose digestion is optimal, it supplies galactose for liver glycogen synthesis. In infants, it cannot be ignored that lactose-derived galactose is needed for the synthesis of glycosylated macromolecules. At least beyond infancy, the low glycemic index of lactose might be metabolically beneficial. When lactase expression decreases, lactose maldigestion may lead to lactose intolerance symptoms. In infancy, the temporary replacing of lactose by other carbohydrates is only justified in case of severe intolerance symptoms. In those who show an (epi)genetic decrease or absence of lactase expression, a certain amount (for adults mostly up to 12 g per portion) of lactose can still be consumed. In these cases, lactose shows beneficial intestinal-microbiota-shaping effects. Avoiding lactose-containing products may imply a lower intake of other important nutrients, such as calcium and vitamin B12 from dairy products, as well as an increased intake of less beneficial carbohydrates.

Genetic and Oral Tests for the Diagnosis of Lactose Intolerance in Mixed-Ancestry Brazilians with Metabolic Syndrome.

BACKGROUND/AIMS: Metabolic syndrome (MetS) comprises a cluster of physiological and anthropometric abnormalities. MetS has been linked to lactose intolerance (LI). The aim of this study was to compare the sensitivity and specificity to detect LI using 2 different tests: (1) a genetic test and (2) an oral lactose tolerance test (OLTT). METHODS: Two hundred and fifty-four MetS patients, ≥20 years of age, of both genders, were recruited for this comparative study. Nine single nucleotide polymorphisms (SNPs) were selected for genetic investigation: rs182549and rs4988235(both considered "gold standard"); rs56064699; rs148142676; rs562211644; rs59533246; rs3754689; rs2278544,and rs10552864(as potential novel SNPs). Sensitivity and specificity, as well as positive and negative predictive values, were calculated for each genotype using WINPEPI version 11.65. Differences between positive and negative OLTT groups were considered statistically significant when p ≤ 0.05. RESULTS: Among the selected SNPs, only rs182549(p < 0.001) and rs4988235(p < 0.001) gave similar results compared to an OLTT. The sensitivity of both SNPs to detect LI was 87 and 86%, and specificity was 83 and 82.5%, respectively. CONCLUSION: Genetic tests using rs182549and rs4988235SNPs showed high agreement with OLTT. These genetic tests may be a good option to replace OLTT in MetS patients.

Full-factorial central composite rotational design for the immobilization of lactase in natural polysaccharide-based hydrogels and hydrolysis of lactose.

A full-factorial central composite rotational design (FFCCRD) was applied for studying the immobilization of lactase in Arabic gum-based and chitosan-based hydrogels, and hydrolysis of lactose. The optimal immobilization capacities of both hydrogels aiming to obtain high immobilized enzyme activity and low released fraction were determined at 25.0 °C, 39.88 mg mL-1 initial enzyme concentration and pH 6.5. The immobilized enzyme activity and released fraction from the Arabic gum-based hydrogel were 0.322 U mg-1 and 0.193, respectively, during the hydrolysis of lactose contained in UHT milk. These values were 0.289 U mg-1 and 0.136, respectively, using a chitosan-based hydrogel. The immobilized enzyme activity and released fraction from these hydrogels during the hydrolysis of standard lactose were 0.246 U mg-1 and 0.407, and 0.211 U mg-1 and 0.245, respectively. The best conditions for the immobilization of lactase and hydrolysis of lactose were achieved by applying FFCCRD, which were compared with experimental results.

Karyotyping and population genetics in Cold War Mexico: Armendares's and Lisker's characterization of child and indigenous populations, 1960s-1980s / Cariotipia e genética de populações no México da Guerra Fria: as caracterizações de Armendares e Lisker sobre as populações infantil e indígena, 1960-1980

Abstract This paper focuses on geneticists Salvador Armendares's and Rubén Lisker's studies from the 1960s to the 1980s, to explore how their work fits into the post-1945 human biological studies, and also how the populations they studied, child and indigenous, can be considered laboratories of knowledge production. This paper describes how populations were considered for different purposes: scientific inquiry, standardization of medical practices, and production or application of medicines. Through the narrative of the different trajectories and collaborations between Armendares and Lisker, this paper also attempts to show the contact of their scientific practices, which brought cytogenetics and population genetics together at the local and global levels from a transnational perspective.

Resumo Aborda o trabalho dos geneticistas Salvador Armendares e Rubén Lisker, entre 1960 e 1980, para analisar como se insere nos estudos biológicos humanos do pós-1945, e demonstra como as populações estudadas por eles, a infantil e a indígena, podem ser consideradas laboratórios de produção de conhecimento. O artigo revela como as populações foram consideradas para diversos propósitos: investigação científica, padronização das práticas médicas e produção ou aplicação de suas medicinas. Por meio da narrativa das diferentes trajetórias e colaborações entre Armendares e Lisker, também procura discutir o contato de suas práticas científicas, que colocaram a citogenética e a genética de populações lado a lado nos níveis local e global a partir de uma perspectiva transnacional.

Lactose intolerance: what is a correct management?

SUMMARY Individuals with Lactose Intolerance (LI) tend to exclude milk from their diet since this behavior seems to relieve the symptoms caused by the disease. However, milk is a food of high nutritional value, and complete exclusion of dairy products may favor the development of bone diseases such as osteopenia and osteoporosis. The objective of this review was to evaluate the scientific evidence on the adequate management of patients with LI. This study was carried out from the review of the scientific literature in PubMed and SciELO databases. Complete exclusion of conventional dairy products is not necessary since most individuals with LI can tolerate up to 12 grams of lactose daily in a single dose. Yogurts and cheeses matured for having low amounts of lactose are part of the strategy that allows consumption of dairy products by patients with LI. Currently, there is a diversity of products considered as "milk substitutes" and supplements aimed at individuals with LI. However, these strategies still require better-designed studies.

RESUMO Os indivíduos com Intolerância à Lactose (IL) tendem a excluir o leite da alimentação, uma vez que essa conduta parece aliviar os sintomas ocasionados pela doença. Entretanto, o leite é um alimento de alto valor nutricional e a exclusão completa dos laticínios pode favorecer o desenvolvimento de doenças ósseas como osteopenia e osteoporose. O objetivo desta revisão foi avaliar as evidências científicas sobre o manejo adequado de pacientes com IL. Este estudo foi realizado a partir da revisão da literatura científica nas bases de dados PubMed e SciELO. A exclusão completa dos produtos lácteos convencionais não é necessária, pois a maior parte dos indivíduos com IL consegue tolerar diariamente até 12 g de lactose em uma única dose. Os iogurtes e queijos maturados, por terem baixa quantidade de lactose, fazem parte da estratégia que garante consumo de produtos lácteos por pacientes com IL. Atualmente existe uma diversidade de produtos considerados "substitutos do leite" e suplementos voltados para os indivíduos com IL, no entanto, essas estratégias ainda requerem estudos mais bem desenhados.

Adaptation to milking agropastoralism in Chilean goat herders and nutritional benefit of lactase persistence.

The genetic trait of lactase persistence (LP) evolved as an adaptation to milking pastoralism in the Old World and is a well-known example of positive natural selection in humans. However, the specific mechanisms conferring this selective advantage are unknown. To understand the relationship between milk drinking, LP, growth, reproduction, and survival, communities of the Coquimbo Region in Chile, with recent adoption of milking agropastoralism, were used as a model population. DNA samples and data on stature, reproduction, and diet were collected from 451 participants. Lactose tolerance tests were done on 41 of them. The European -13,910*T (rs4988235) was the only LP causative variant found, showing strong association (99.6%) with LP phenotype. Models of associations of inferred LP status and milk consumption, with fertility, mortality, height, and weight were adjusted with measures of ancestry and relatedness to control for population structure. Although we found no statistically significant effect of LP on fertility, a significant effect (P = 0.002) was observed of LP on body mass index (BMI) in males and of BMI on fertility (P = 0.003). These results fail to support a causal relationship between LP and fertility yet suggest the idea of a nutritional advantage of LP. Furthermore, the proportion of European ancestry around the genetic region of -13,910*T is significantly higher (P = 0.008) than the proportion of European ancestry genome-wide, providing evidence of recent positive selection since European-Amerindian admixture. This signature was absent in nonpastoralist Latin American populations, supporting the hypothesis of specific adaptation to milking agropastoralism in the Coquimbo communities.

Efecto de los residuos fibrosos de avena ( Avena sativa ) y caraotas ( Phaseolus vulgaris ) sobre la actividad in vitro de las disacaridasas intestinales en ratas / Effect of the Fibrous Residues of Avena (Avena sativa) and Black Beans (Phaseolus vulgaris) on the in vitro Activity of Intestinal Disacaridases in Rats

Resumen Antecedentes: las disacaridasas intestinales pueden ser inhibidas o estimuladas parcialmente en presencia de fibra. Objetivo: evaluar el efecto de los residuos fibrosos de avena (Avena sativa) y caraotas (Phaseolus vulgaris) sobre la actividad in vitro de las disacaridasas intestinales. Materiales y métodos: 15 ratas Sprague Dawley se dividieron en tres grupos: un grupo control, un grupo alimentado con harina de caraota y un grupo alimentado con harina de avena, durante 21 días. Se obtuvo un homogeneizado de la mucosa intestinal que fue utilizado para la determinación de la actividad de las disacaridasas por un método enzimático, en presencia de sustrato natural y con la adición de residuos fibrosos de harina de avena y caraotas en concentración de 2,5 % (P/V). Resultados: la mayor actividad enzimática se registró en la región intestinal media para cada enzima (p<0,05). El orden de actividad enzimática en mg glucosa/mg proteína/min fue maltasa (0,149) sacarasa (0,096) y lactasa (0,014) (p<0,05). La maltasa fue inhibida en mayor medida por el residuo de caraota; la sacarasa, por el residuo de avena; y la lactasa, por ambos. Conclusiones: la adición de fibra purificada de avena y caraota produjo una disminución significativa de la actividad in vitro de las disacaridasas intestinales, especialmente en presencia del residuo de caraota.

Abstract Background: Intestinal disaccharidases can be partially inhibited or stimulated in the presence of fiber. Objective: To evaluate the effect of fibrous residues of oats (Avena sativa) and black beans (Phaseolus vulgaris) on the "in vitro" activity of the intestinal disaccharidases. Materials and Methods: 15 Sprague Dawley rats, were divided into three groups: control, fed with bean flour, and fed with oatmeal flour for 21 days. Homogenate was obtained by scraping the mucosa. The determination of enzymatic activity of the disaccharidases was measured by the enzymatic method, in the presence of its natural substrate and with addition of the fibrous residues obtained from the oatmeal and black beans, in concentration of 2.5 % (W/V). Results: The highest enzymatic activity was recorded in the middle intestinal region for each enzyme (p <0.05). The order of enzymatic activity in mg glucose / mg protein / min was maltase (0.149) sucrase (0.096) and lactase (0.014) (p<0.05). Maltase was inhibited to a greater extent by bean residue; sucrase by oat residue and lactase by both. Conclusion: The addition of purified fiber of oats and bean produced a significant decrease in the in vitro activity of the intestinal disaccharidases, especially in the presence of the bean residue.

Classificação da intolerância à lactose: uma visão geral sobre causas e tratamentos / Classification of lactose intolerance: An overview of causes and treatments

A deficiência total ou parcial da enzima denominada lactase, responsável por hidrolisar em glicose e galactose a lactose presente no leite, é popularmente conhecida como intolerância à lactose. No presente trabalho foram revisadas as causas e tratamentos para intolerância à lactose. Foi realizada uma revisão retrospectiva e integrativa da literatura nas bases SciELO, MedLine e PubMed. A intolerância possui três classificações: primária, secundária e congênita. A intolerância ontogenética à lactose ou hipolactasia primária adulta é a forma mais comum. Já a deficiência secundária consiste em um quadro fisiopatológico que tem como consequência a má absorção de lactose. Por fim, a intolerância congênita à lactose é uma deficiência de herança genética, que acomete recém-nascidos nos primeiros dias de vida. Na hipolactasia, o agravamento surge na vida adulta, justamente com perda da função gradativa da enzima que degrada a lactose. Isso ocorre pelo fato de essa enzima, presente e ativa durante a amamentação em mamífero, perder sua função no início do desmame. Em pacientes não intolerantes, essa mesma enzima passa por um processo de mutação, permanecendo ativa ao longo da vida adulta. O tratamento mais comum para pacientes com intolerância à lactose envolve a retirada total ou parcial do leite e seus derivados, já que a supressão total causa alguns danos à nutrição e à manutenção do organismo.

The total or partial deficiency of lactase, responsible for hydrolyzing lactose into glucose and galactose, is popularly known as lactose intolerance. In this work we reviewed the causes and treatments for lactose intolerance. An integrative and retrospective literature review was carried out at the SciELO, MedLine and PubMed databases. Intolerance has three classifications: primary, secondary and congenital. The ontogenetic lactose intolerance or adult primary hypolactasia is the most common form. The secondary deficiency consists of a pathophysiological which results in the absorption of lactose. Congenital lactose intolerance is a genetic inheritance disability that affects infants in the first days of life. In the hypolactasia, aggravation arises in adulthood, just with gradual loss of function of the enzyme that breaks down lactose. This enzyme, present and active during breastfeeding in mammalian, starts losing its function at the weaning. In non intolerant patients this same enzyme passes through a changing process which remains active throughout adult life. The most common treatment for patients with lactose intolerance involves partial or total removal of the milk and its products since the total withdrawal causes some damage to nutrition and maintenance of body.

Tailoring Nutritional Advice for Mexicans Based on Prevalence Profiles of Diet-Related Adaptive Gene Polymorphisms.

Diet-related adaptive gene (DRAG) polymorphisms identified in specific populations are associated with chronic disorders in carriers of the adaptive alleles due to changes in dietary and lifestyle patterns in recent times. Mexico's population is comprised of Amerindians (AM) and Mestizos who have variable AM, European (EUR) and African genetic ancestry and an increased risk of nutrition-related chronic diseases. Nutritional advice based on the Mexican genome and the traditional food culture is needed to develop preventive and therapeutic strategies. Therefore, we aimed to provide a prevalence profile of several DRAG polymorphisms in the Mexican population, including Central West (CW) Mexico subpopulations. Geographic heat maps were built using ArcGIS10 (Esri, Redlands, CA, USA) software, based on the published data of the MTHFR C677T (rs1801133), ABCA1 Arg230Cys (rs9282541), APOE T388C (rs429358)/C526T (rs7412), LCT C-13910T (rs4988235) polymorphisms and AMY1 copy number variation (CNV). Also, new data obtained by allelic discrimination-real-time polymerase chain reaction (RT-PCR) assays for the MTHFR, ABCA1, and APOE polymorphisms as well as the AMY1 CNV in the CW Mexico subpopulations with different proportions of AM and EUR ancestry were included. In the CW region, the highest frequency of the MTHFR 677T, ABCA1 230C and APOE ε4 adaptive alleles was observed in the AM groups, followed by Mestizos with intermediate AM ancestry. The LCT-13910T allele frequency was highest in Mestizos-EUR but extremely low in AM, while the AMY1 diploid copy number was 6.82 ± 3.3 copies. Overall, the heat maps showed a heterogeneous distribution of the DRAG polymorphisms, in which the AM groups revealed the highest frequencies of the adaptive alleles followed by Mestizos. Given these genetic differences, genome-based nutritional advice should be tailored in a regionalized and individualized manner according to the available foods and Mexican traditional food culture that may lead to a healthier dietary pattern.

Frequency of adult type-associated lactase persistence LCT-13910C/T genotypes in the Czech/Slav and Czech Roma/Gypsy populations

Abstract Lactase non-persistence (leading to primary lactose intolerance) is a genetically dependent inability to digest lactose in adulthood. As part of the human adaptation to dairying, the human lactase LCT-13910C/T mutation (which propagates adult expression of lactase) developed, spread and participated in the adaptation to dairying. This variant is associated with lactase activity persistence, and its carriers are able to digest lactose. We compared the frequencies of lactase 13910C/T (rs4988235) genotypes in Czechs/Slavs (N = 288) and Czech Gypsies/Roma (N = 300), two ethnically different groups where this polymorphism has not yet been analysed. Allelic frequencies significantly differed between the populations (p < 0.0001). In Czechs/Slavs, the lactase persistence T allele was present in 76% of the individuals, which is in agreement with frequencies among geographically neighbouring populations. In the Czech Gypsy/Roma population, only 27% of the adults were carriers of at least one lactase persistence allele, similar to the Indian population. In agreement with this result, dairy product consumption was reported by 70.5% of Czechs/Slavs and 39.0% of the Czech Gypsy/Roma population. Both in the Czech Gypsy/Roma and in the Czech/Slavs populations, the presence of carriers of the lactase persistence allele was similar in subjects self-reporting the consumption of unfermented/fresh milk, in comparison to the others.