RESUMO
Background and objectives: The development of the oral microbiome begins in the prenatal stage. Breast milk contains antimicrobial proteins, microorganisms, metabolites, enzymes, and immunoglobulins, among others; therefore, differences have been noted in the type of microorganisms that colonize the oral cavity of children who are breastfed compared to those who are formula-fed. Our objective was to establish the relationship between breastfeeding, formula feeding, or mixed feeding (breastfeeding and formula) with the presence of S. mutans in a population of children under 6 months of age. Materials and Methods: The patients were recruited from the Child Care Center of Ciudad Juárez, Chihuahua, and from the pediatric dentistry postgraduate clinics of the Autonomous University of Ciudad Juárez; children exclusively fed maternally, with formula, and/or mixed were included. Those who had been fed within the previous hour were excluded. The sample was taken with a smear of the jugal groove using a sterile micro-brush. For the identification of Streptococcus mutans, a culture of Mitis Salivarius Agar (Millipore) was used. Results: 53.3% corresponded to females and 46.7% to males, 36.7% corresponded to maternal feeding, 23.3% corresponded to formula feeding, and 40% corresponded to mixed feeding. In 90% of the infants, the parents indicated that they did not perform oral hygiene. The CFU count showed that infants who were exclusively breastfed had an average of 9 × 10 CF/mL, formula-fed infants had an average of 78 × 10 CFU/mL, and those who had mixed feeding 21 × 10 CFU/mL. Conclusions: According to the results obtained, it was possible to corroborate that exclusive breastfeeding limits the colonization of Streptococcus mutans compared to those infants who receive formula or mixed feeding; these results could have a clinical impact on the dental health of infants by having a lower presence of one of the main etiological factors involved in dental caries and the type of microbiome established in the oral cavity.
Assuntos
Aleitamento Materno , Leite Humano , Boca , Streptococcus mutans , Humanos , Streptococcus mutans/isolamento & purificação , Leite Humano/microbiologia , Feminino , Lactente , Masculino , Boca/microbiologia , Fórmulas Infantis/estatística & dados numéricos , Recém-NascidoRESUMO
The diet is the main route that polycyclic aromatic hydrocarbons (PAHs) enter the body and measuring breast milk is one of the best ways to understand the maternal body burden and can be passed on to infants. In this study, it was determinate the concentrations of 23 PAHs in 60 milk samples taken from 3 cities in Colombia and to determine the potential routes of exposure and risk to human health. On average, concentration for the ∑PAHs across all locations was 186.6 ng g-1, lipid mass (LM), with city means of 260.1, 175.7, and 123.9 ng g-1 LM for Cartagena, Bogota and Medellin, respectively. Monte Carlo simulations were used to estimate the hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) for infant dietary exposure to PAHs. HQs were below the safe thresholds (HQ = 1) while ILCRs were greater than the reference value equal to 10-6 (mg kg-1day-1). Dietary source assessment indicated that fish is a significant source of PAHs, with mothers that consumed fish at least once per week having â¼2.5 times greater PAH milk concentrations than other groups. While a disparity was also observed among consumers of exclusively marine (∑PAHs 198.5 ng g-1 LM) or freshwater fish (∑PAHs 85.7 ng g-1 LM). However, geographical considerations can be significant in this finding.
Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Animais , China , Colômbia , Monitoramento Ambiental , Feminino , Humanos , Lactente , Leite Humano/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de RiscoRESUMO
Persistent organic pollutants (POPs) are organic compounds that resist biochemical degradation, moving long distances across the atmosphere before deposition occurs. Our goal was to provide up-to-date data on the levels of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in breast milk from Chilean women and to estimate the exposure of infants due to breast milk consumption. In Chile, we conducted a cross-sectional study based on methodologies proposed by the WHO, with a sample of 30 women recruited from three defined areas: 10 from the Arica Region (urban; Arica and Parinacota Region), 10 from Coltauco (rural; O'Higgins Region), and 10 from Molina (40% rural; Maule Region). High-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC/HRMS) was performed on pooled samples from each area. We calculated equivalent toxic concentrations (WHO-TEQ) based on the current WHO Toxic Equivalency Factors (TEF). The minimum and maximum values of ∑ PCDDs/Fs + DL-PCBs-TEQ were 4.317 pg TEQ/g fat in Coltauco and 6.31 pg TEQ/g fat in Arica. Molina had a total TEQ of 5.50 pg TEQ/g fat. The contribution of PCDD/Fs was approximately five-fold higher than that of DL-PCBs. The Estimated Daily Intake (EDI) of ∑ PCDDs/Fs + DL-PCBs based on the three pooled samples ranged between 6.71 and 26.28 pg TEQ/kg body weight (bw)/day, with a mean intake of 16.11 (±6.71) pg TEQ/kg bw/day in breastfed children from 0 to 24 months old. These levels were lower than those reported in international studies. Despite the fact that the observed levels were low compared to those in most industrialized countries, the detection of a variety of POPs in breast milk from Chilean women indicates the need for follow-up studies to determine whether such exposures during childhood could represent a health risk in adulthood.
Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Adulto , Animais , Benzofuranos/análise , Criança , Pré-Escolar , Chile , Estudos Transversais , Dibenzofuranos , Dioxinas/análise , Feminino , Furanos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Recém-Nascido , Leite Humano/química , Projetos Piloto , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análiseRESUMO
Human breast milk contains a diverse community of bacteria, but as breast milk microbiome studies have largely focused on mothers from high income countries where few women breastfeed to 6 months, the temporal changes in the breast milk microbiome that occur during later lactation stages have not been explored. For this cross-sectional study, microbiota from breast milk samples of Mam-Mayan mothers living in eight remote rural communities in the Western Highlands of Guatemala were analyzed. All mothers delivered vaginally and breastfed their infants for 6 months. Breast milk from 76 unrelated mothers was used to compare two lactation stages, either "early" (6-46 days post-partum, n = 33) or "late" (109-184 days post-partum, n = 43). Breast milk microbial communities were assessed using 16S ribosomal RNA gene sequencing and lactation stages were compared using DESeq2 differential abundance analysis. A total of 1,505 OTUs were identified, including 287 which could be annotated as putative species. Among several maternal factors, lactation stage explained microbiome variance and inertia in ordination with the most significance (p < 0.001). Differential abundance analysis identified 137 OTUs as significantly higher in either early or late lactation. These included a general shift from Staphylococcus and Streptococcus species in early lactation to Sphingobium and Pseudomonas species in late lactation. Species enriched in early lactation included putative commensal bacteria known to colonize the infant oral and intestinal tracts whereas species enriched in late lactation had a uniform functional trait associated with aromatic compound degradation. Differentially abundant species also included several species which have not previously been reported within breast milk, such as Janthinobacterium agaricidamnosum, Novosphingobium clariflavum, Ottowia beijingensis, and Flavobacterium cucumis. These discoveries describe temporal changes to the breast milk microbiome of healthy Guatemalan mothers from early to late lactation. Collectively, these findings illustrate how studying under-represented human populations might advance our understanding of factors that modulate the human milk microbiome in low and middle income countries (LMIC).
RESUMO
Breast milk can be a source of potential probiotic bacteria, but the technological capacity of isolates obtained from this source is not always guaranteed. We aimed at isolating lactobacilli from breast milk samples collected in Argentina, focusing on isolates with functional and technological potential as probiotics. Fourteen Lactobacillus and one Bifidobacterium isolates were obtained from 164 samples donated by 104 mothers. The isolates preliminarily identified by MALDI-TOF, and then the identity was confirmed by partial 16S rRNA gene sequencing. Hydrophobicity was determined (hexadecane and xylene partition). The strains were also co-cultured with murine RAW 264.7 macrophages for screening the capacity to induce the anti-inflammatory cytokine interleukin (IL)-10. Hydrophobicity ranged from 7.4 and 95.9%. The strains Lactobacillus gasseri (70a and 70c) and Lactobacillus plantarum (73a and 73b) were the strains with a higher capacity to induce IL-10 production by macrophages. The technological application was evaluated by freezing dried in 10% lactose or 10% polydextrose. The survival was assessed after accelerated (37 °C, 4 weeks) or long-term (5 and 25 °C, 12 months) storage. Except for Lactobacillus gallinarum 94d, strains lost less than 1 Log10 order cfu/g after long-term (12 months) storage at 5 °C in lactose and polydextrose as protectants. A low correlation between survival to accelerated and long-term storage tests was observed. L. gasseri (70a and 70c) and L. plantarum (73a and 73b) deserve further studies as potential probiotics due to their capacity to induce IL-10 from murine macrophages and their hydrophobicity. In special, L. plantarum 73a was able to confer enhanced protection against Salmonella infection by promoting the immunity of the small intestine.
Assuntos
Bactérias/isolamento & purificação , Leite Humano/microbiologia , Probióticos , Animais , Argentina , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Meios de Cultura , Feminino , Liofilização , Variação Genética , Humanos , Interações Hidrofóbicas e Hidrofílicas , Interleucina-10/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Viabilidade Microbiana , Probióticos/química , Probióticos/farmacologiaRESUMO
WHO recommends breastfeeding for the first 6 months of newborn's life. Due to its physicochemical properties, breast milk may contain undesirable components originated from mother's feeding, medication and illicit drugs consumption. Some of these substances transferred from bloodstream to milk and delivered to the infant can cause harmful effects. For the last decades, analytical advances enabled the analysis of several substances in milk using different techniques. Thereby, it is possible to evaluate infant's level of exposure to these substances. This review presents the information published in the main scientific dissemination media about psychoactive drugs investigation in human breast milk, involving the sample preparation techniques and chromatographic validated methods developed in the past 10 years.
Assuntos
Leite Humano/química , Psicotrópicos/análise , Adolescente , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Adulto JovemRESUMO
The aim of this research was to quantify essential trace elements (iron, copper, zinc and iodine) and establish their speciation in human milk. Both the element and the species are important in new-born nutrition. Colostrum, and transitional and mature milks (25) were collected from 18 mothers of pre-term or full-term infants. Concentrations of the target elements were determined using ICP-MS. For speciation, HPLC coupled to ICP-MS was employed. Total contents of the micronutrients varied in mothers of pre-term (Fe = 0.997, Cu = 0.506, Zn = 4.15 and I = 0.458 mg L-1) and mothers of full-term (Fe = 0.733, Cu = 0.234, Zn = 2.91 and I = 0.255 mg L-1) infants. Fe, Cu and Zn were associated with biomolecules with high molecular mass compounds, such as immunoglobulins, albumin and lactoferrin whilst iodine was only found as iodide.
Assuntos
Cobre/análise , Iodo/análise , Ferro/análise , Espectrometria de Massas/métodos , Leite Humano/química , Zinco/análise , Adulto , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Iodo/isolamento & purificação , Ferro/isolamento & purificação , Gravidez , Zinco/isolamento & purificaçãoRESUMO
BACKGROUND: Subclinical mastitis (SCM) is an inflammatory condition of the mammary gland, but its association with human milk composition and infant growth is not well described. OBJECTIVES: We investigated whether SCM, milk cytokines, and/or estimated intakes of milk minerals and trace elements were associated with infant anthropometry or growth velocity before 6 mo. METHODS: Breast milk was collected from Mam-Mayan mothers (n = 114) at both early (2-46 d) and established (4-6 mo) lactation. Concentrations of 9 elements (sodium, potassium, calcium, magnesium, copper, iron, manganese, selenium, zinc) analyzed by inductively-coupled plasma mass spectrometry were used to estimate infants' daily intakes. Concentrations of 4 cytokines were measured. Milk concentrations and infants' estimated elemental intakes and anthropometric measurements during early and established lactation were compared by SCM status. Multiple regression was used to identify factors associated with infant growth attainment (<46 d) for infant weight- (WAZ), length- (LAZ), and head circumference-for-age (HCAZ) and weight-for-length (WLZ) z scores and with growth velocity (expressed as Δ/d) from early to established lactation. RESULTS: SCM prevalence was higher in early (30%) than established (10%) lactation. Breast milk of SCM mothers had higher cytokine concentrations and higher magnesium in early and higher selenium concentrations in both early and established lactation (Padj < 0.0121). At day 46, regression models showed inverse associations of SCM with WLZ and IL-1ß with LAZ (Padj < 0.0150). In contrast, linear growth velocity was positively associated with IL-1ß measured in early lactation (Padj < 0.0124), whereas cranial growth velocity was positively associated with IL-8 measured during established lactation ( Padj < 0.0124). CONCLUSIONS: Despite a high prevalence of inadequate intakes, only infants' intake of milk magnesium during early lactation was associated with linear growth velocity in breastfed infants <6 mo. Evidence shows that SCM, breast-milk cytokines, and infants' estimated intakes of select elements are independently associated with growth attainment and growth velocity during lactation.
Assuntos
Estatura , Peso Corporal , Aleitamento Materno , Citocinas/análise , Mastite/etiologia , Leite Humano/química , Minerais/análise , Oligoelementos/análise , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Inflamação/etiologia , Estudos LongitudinaisRESUMO
BACKGROUND: Human milk is a dynamic food and some important differences in composition can be found between the milk from preterm and terms infants. Additionally, in some situations, the mother's own milk is unavailable and the use of milk from human milk banks is considered as the most appropriate substitute. In this way, concentrations of trace elements (Ba, Cu, Fe, Mn, Mo, Se, Sr, and Zn) were determined in human milk, considering the differences about preterm and term human milk and its processing in a human milk bank. METHODS: A total of 156 samples were analyzed, which were divided in three groups: samples collected at the hospital at bedside (BS, 60 samples) from mothers of preterm infants and samples from mothers of term infants collected in a human milk bank without pasteurization (WP, 49 samples) and pasteurized by the Holder procedure (P, 47 samples). The analyzes were conducted by inductively coupled plasma mass spectrometry (ICP-MS) after the treatment of the samples with acid mineralization assisted by microwave radiation. RESULTS: Concentrations varied in a range of 0.6-88.2 µg/L for Ba, 78.6-954.5 µg/L for Cu, 24.2-5229.2 µg/L for Fe, 0.4-42.6 µg/L for Mn, 0.1-39.1 µg/L for Mo, 2.5-70.6 µg/L for Se, 8.9-187.5 µg/L for Sr and 76.3-17727.2 µg/L for Zn. Significant differences (p < 0.05) were found between preterm (BS) and term human milk (WP and P) for Ba, Cu, Mo, Se, and Zn, whereas the processing of the donated milk by Holder pasteurization did not influence the concentration of the studied trace elements. The milk of term infants does not attend the recommended daily intake (RDI) of Zn and for preterm infants the RDI of Fe and Mn is not achieved. CONCLUSIONS: The higher concentrations of Cu, Mo, Se and Zn observed in milk from mothers of preterm infants indicate that the milk to be offered for these high-risk neonates in neonatal intensive care units should contain higher levels of these trace elements. Besides, considering the RDI, the milk of term infants should be fortified with Zn, whereas the milk of preterm infants should be fortified with Fe.
Assuntos
Leite Humano/química , Oligoelementos/análise , Brasil , Cobre/análise , Feminino , Humanos , Recém-Nascido , Espectrometria de Massas/métodos , Molibdênio/análise , Mães , Selênio/análise , Zinco/análiseRESUMO
We aimed at isolating and characterising microorganisms present in human breast milk with probiotic potential. In an 8-week postpartum sampling period, two strains of bifidobacteria (Bifidobacterium longum LM7a and Bifidobacterium dentium LM8a') and four strains of lactobacilli were isolated, all during the first 4-week postpartum. B. longum LM7a and B. dentium LM8a', together with four strains previously isolated from breast milk (Bifidobacterium lactis INL1, INL2, INL4 and INL5), were considered for further studies. Susceptibility of the strains to tetracycline, erythromycin, clindamycin, streptomycin, vancomycin and chloramphenicol was evaluated and the isolates exhibited, in general, the same properties as previously reported for bifidobacteria. All isolates showed low hydrophobicity and B. lactis and B. longum strains had satisfactory resistance to gastric digestion and bile shock, but not to pancreatin. B. lactis INL1, B. longum LM7a and B. dentium LM8a' were selected for some comparative technological studies. In particular, B. lactis INL1 displayed technological potential, with satisfactory growth in cheese whey-based media in biofermentor and resistance to freeze-drying, accelerated storage conditions and simulated gastric digestion.
Assuntos
Bifidobacterium/isolamento & purificação , Meios de Cultura/química , Lactobacillus/isolamento & purificação , Leite Humano/microbiologia , Probióticos/efeitos adversos , Probióticos/isolamento & purificação , Soro do Leite/metabolismo , Antibacterianos/farmacologia , Bifidobacterium/efeitos dos fármacos , Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Ácidos e Sais Biliares/toxicidade , Feminino , Ácido Gástrico/metabolismo , Humanos , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Lactobacillus/metabolismo , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Pancreatina/toxicidadeRESUMO
Parabens have been widely used as antimicrobial preservatives in food, drugs, and cosmetics for over 60â¯years. These endocrine disruptors can alter both the wildlife and the human hormone function. Determining these compounds in human milk is important because breast milk plays an important role in infant growth and in neurocognitive development. This article summarizes the current state-of-the-art of chromatographic methods to determine parabens in breast milk samples. Apart from the conventional and modern microextraction sample preparation techniques described herein, the authors discuss the chromatographic systems, primarily LC-MS/MS, and the concentration ranges at which parabens have been detected in milk samples obtained from lactating women over the past few years.
Assuntos
Fracionamento Químico , Cromatografia Líquida , Leite Humano/química , Parabenos/análise , Feminino , Humanos , Espectrometria de Massas em TandemRESUMO
Levels of essential metals in human breast milk (HBM) have been determined by different analytical techniques, but there is few woks about human whey milk fractions. However, the current trend lies in metalloproteomic and identification of different metalloproteins. In this sense, native separative techniques (N-PAGE and SEC) coupled to ICP-MS provide us with valuable information. Besides it is necessary the development of new methodologies in order to determine with accuracy and precision the profile of such metals and metalloproteins in the different whey protein fractions of HBM. Thus, the aim of this work was to develop a new method for metals and metalloproteins determination by SEC-ICP-MS in whey protein fractions of HBM. Human whey fractions were obtained of HBM samples by ultracentrifugation. Then, protein fractions of whey milk were separated by SEC coupled to ICP-MS for metalloproteins and Mn, Co, Cu and Se quantification. Besides, protein profile of whey milk was determined by N-PAGE and computer assisted image analysis. SEC-ICP-MS results indicated that first and second protein fractions showed detectable levels of the Mn, Co, Cu, and Se. Protein profile determined by N-PAGE and image analysis showed that molecular weight of protein fractions ranged between 68,878-1,228.277â¯Da. In this work, metalloproteins were analyzed by SEC coupled to ICP-MS, with adequate sensitivity and accuracy. Our study has shown the presence of Mn, Co, Cu and Se bound to two protein fractions in whey milk of HBM. Metals levels analyzed were within the ranges reported in the literature.
Assuntos
Metaloproteínas/análise , Metais/análise , Micronutrientes/análise , Leite Humano/química , Adulto , Cromatografia em Gel/instrumentação , Cromatografia em Gel/métodos , Estudos de Viabilidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Eletroforese em Gel de Poliacrilamida Nativa/instrumentação , Eletroforese em Gel de Poliacrilamida Nativa/métodos , Sensibilidade e Especificidade , Proteínas do Soro do Leite/análiseRESUMO
BACKGROUND: Breast milk is the recommended source of nutrients for infant growth, but its adequacy to meet infants' mineral and trace element needs is unknown. OBJECTIVES: We used breast-milk mineral and trace element concentrations of Guatemalan mothers at 3 lactation stages to estimate total daily intakes and to determine whether intakes were associated with early infant growth. METHODS: In this cross-sectional study, breast-milk samples were collected from Mam-Mayan mothers during transitional (5-17 d, n = 56), early (18-46 d, n = 75), and established (4-6 mo, n = 103) lactation; z scores for weight (WAZ), length (LAZ), and head circumference (HCAZ) were measured. Concentrations of 11 minerals (calcium, potassium, magnesium, sodium, copper, iron, manganese, rubidium, selenium, strontium, and zinc) were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). WHO equations were used to calculate the estimated energy requirement, which was divided by the energy density of breast milk to estimate daily milk volume, and this number was multiplied by breast-milk mineral concentrations to estimate intakes. Principal component analyses identified clusters of minerals; principal components (PCs) were used in regression analyses for anthropometric outcomes. RESULTS: Estimated breast-milk intakes during established lactation were insufficient to compensate for the lower milk sodium, copper, manganese, and zinc concentrations in male infants and the lower sodium, iron and manganese concentrations in female infants. Estimated intakes of calcium, magnesium, potassium, sodium, and selenium were below the Institute of Medicine Adequate Intake for both sexes at all 3 stages of lactation. In early lactation, multiple linear regressions showed that PC1 (calcium, magnesium, potassium, rubidium, and strontium intakes) was positively associated with WAZ, LAZ, and HCAZ. In established lactation, the same PC with sodium added was positively associated with all 3 anthropometric outcomes; a second PC (PC2: zinc, copper, and selenium intakes) was associated with WAZ and LAZ but not HCAZ. CONCLUSIONS: Breast milk may be inadequate in selected minerals and trace elements where higher estimated intakes were associated with greater infant growth.
Assuntos
Fenômenos Fisiológicos da Nutrição do Lactente , Leite Humano/química , Oligoelementos/análise , Peso Corporal , Aleitamento Materno , Estudos Transversais , Feminino , Guatemala , Humanos , Lactente , Lactação , Modelos Lineares , Masculino , Avaliação Nutricional , Necessidades Nutricionais , Análise de Componente Principal , Oligoelementos/administração & dosagem , Oligoelementos/deficiência , Organização Mundial da SaúdeRESUMO
There is an urgent need to identify environmental risk and protective factors in early life for the prevention of allergy. Our study demonstrates the presence of respiratory allergen from house dust mite, Der p 1, in human breast milk. Der p 1 in milk is immunoreactive, present in similar amounts as dietary egg antigen, and can be found in breast milk from diverse regions of the world. In a mouse model of asthma, oral exposure to Der p through breast milk strongly promotes sensitization rather than protect the progeny as we reported with egg antigen. These data highlight that antigen administration to the neonate through the oral route may contribute to child allergic sensitization and have important implications for the design of studies assessing early oral antigen exposure for allergic disease prevention. The up-to-now unknown worldwide presence of respiratory allergen in maternal milk allows new interpretation and design of environmental control epidemiological studies for allergic disease prevention.
Assuntos
Alérgenos/imunologia , Asma/imunologia , Leite Humano/imunologia , Pyroglyphidae/imunologia , Animais , Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Colostro/imunologia , Cisteína Endopeptidases/imunologia , Exposição Ambiental/efeitos adversos , Feminino , Humanos , GravidezRESUMO
El objetivo del estudio fue evaluar la capacidad inmunomoduladora de dos cepas de L. paracasei (66 y 71) y una de L. rhamnosus (75) aisladas de leche materna y heces de lactante, en Mérida, Venezuela, caracterizadas como potencialmente probióticas en estudios previos. Las bacterias fueron administradas a ratones BALB/c en el agua de bebida durante 7 días. Con los fluidos intestinales se realizaron pruebas de ELISA para determinar los valores de las citoquinas IFN-γ e IL-10. Se realizó la coloración de hematoxilina-eosina a cortes histológicos del intestino delgado para observar posibles reacciones inflamatorias. Para el análisis estadístico, se utilizó la prueba de ANOVA de una vía, seguido del test post hoc de Tukey, considerando a p<0,05 como significativo. Se observaron incrementos significativos, por encima del grupo control, en las concentraciones de IFN-γ e IL-10 en el fluido intestinal de los ratones alimentados con las cepas 71 y 75. No se observaron reacciones inflamatorias en el intestino delgado. Al inducir un aumento en la producción de las citoquinas, estas cepas fueron capaces de estimular el sistema inmune manteniendo la homeostasis, por lo que pueden ser utilizadas como adyuvantes del sistema inmune intestinal, sin producir efectos secundarios indeseables.
The objective of this study was to evaluate the immunomodulating capacity of two L. paracasei strains (66 and 71), and one L. rhamnosus (75) isolated from breast milk and lactating children feces in Mérida, Venezuela, characterized as potentially probiotic in previous studies. The bacteria were administered to BALB/c mice in their drinking water during 7 days. Intestinal fluids were tested by ELISA to determine IFN-γ and IL-10 cytokines values. Histological sections of the small intestine were stained with hematoxilin-eosin to detect possible inflammatory reactions. The statistical analysis was done by a one way ANOVA, followed by the Tukey post hoc test, considering p<0.05 as significant. There were significant increases, as compared with the control group, of INF-γ and IL.10 concentrations in the intestinal fluid of mice fed with strains 71 and 75. There were no inflammatory reactions of the small intestine tissue. By inducing an increase in cytokine production, these strains were capable of stimulating the immune system maintaining homeostasis, due to which they can be used as adjuvant of the immune intestinal system, without producing undesirable side effects.
RESUMO
OBJETIVOS: Avaliar a composição de ácidos graxos do leite humano maduro de mulheres residentes em área distante da costa litorânea brasileira. MÉTODOS: Amostras de leite materno maduro foram obtidas de 47 mulheres lactantes com idade entre 18 e 35 anos, que tiveram partos a termo e em aleitamento exclusivo ou predominante. A coleta de leite se deu a partir da 5ª semana pós-parto, por meio de ordenha manual. A composição de ácidos graxos do leite foi determinada por cromatografia gasosa. RESULTADOS: Verificou-se que a concentração de eicosapentaenoico (0,08%) foi superior ao observado em estudos brasileiros prévios. Entretanto, o teor de docosahexaenoico (0,09%) encontrado no leite humano foi um dos menores já verificados no mundo. O teor de ácidos graxos trans (2,05%) foi similar ao relatado em estudos nacionais prévios à obrigatoriedade de declaração do teor deste em rótulos de alimentos, sugerindo que esta medida não surtiu efeito na redução de seu teor na dieta habitual das mulheres. CONCLUSÕES: Baixo teor de docosahexaenoico e elevada concentração de ácidos graxos trans foram verificados no leite materno maduro de mulheres residentes em área distante da costa litorânea brasileira.
OBJECTIVES: To evaluate the fatty acid composition of mature human milk of women living far from the coastal area of Brazil. METHODS: Mature breast milk samples were obtained from 47 lactating women aged between 18 and 35 years, who delivered their babies at term and who exclusively or predominantly breastfed. Milk collection took place after the fifth week postpartum by hand expression. The fatty acid composition of the milk was determined by gas chromatography. RESULTS: It was observed that the concentration of eicosapentaenoic acid (0.08%) was higher than that observed in previous studies in Brazil. However, the content of docosahexaenoic acid (0.09%) found in human milk was one of the lowest verified in the world. The content of trans fatty acids (2.05%) was similar to that reported in national studies previous to the mandatory declaration of this fatty acid content in food labels, suggesting that this measure had no effect on reducing the content of this fatty acid in the usual diet of women. CONCLUSIONS: Low levels of docosahexaenoic acid and high concentrations of trans fatty acids were observed in mature breast milk of women living far from the coastal area in Brazil.