Maternal hypertension induces alterations in immunological factors of colostrum and human milk

Nutritional composition of human milk and its association with maternal and perinatal factors

OBJECTIVE

The objective of this study was to evaluate the influence of maternal and perinatal factors on the nutritional composition of human milk.

METHODS

A cross-sectional study was conducted between November 2018 and January 2020, with 181 donors selected in Tertiary Health Units of the Unified Health System - from one collection station and five Human Milk Banks. Data were collected through a standardized questionnaire. To be fit to be a donor in a Human Milk Banks and produce mature milk were the eligibility criteria to participate in the study. We excluded milk samples with Dornic acidity above 8° D. The dependent variables were the macronutrients of human milk (i.e., carbohydrates, proteins, lipids, and total energy), that were analyzed using spectroscopy with the Miris Human Milk Analyzer™. The maternal and perinatal factors were the independent variables.

RESULTS

Women with pre-gestational obesity and gestational weight gain above the recommendation showed a lower protein concentration compared to eutrophic women (median=0.8, interquartile range (IQR): 0.7-0.9 vs. median=0.8, and IQR: 0.8-1.0) and those with adequate gestational weight gain (median=0.8, IQR: 0.7-0.9 vs. median=0.9, and IQR: 0.8-1.0), respectively. The other analyzed factors (i.e., maternal habits, comorbidities, and perinatal factors) were not associated with the nutritional composition of human milk.

CONCLUSIONS

The assessment of factors associated with the nutritional composition of human milk is extremely important to assist postpartum care. Pre-gestational obesity and inadequate gestational weight gain were the only factors statistically associated with the nutritional composition of human milk as they impacted its protein content.

The Influence of the Lactation Period and the Type of Milk on the Content of Amino Acids and Minerals in Human Milk and Infant Formulas

(1) Background: This study investigated the effect of the lactation period and the type of infant formula on the content of amino acids and selected minerals in an infant's food; (2) Methods: The study material consisted of breast milk (colostrum, n = 38; transitional milk, mature milk, n = 38) and three types of infant formulas (for first and follow-on feeding). Amino acid content was determined using an automatic amino acid analyzer, while minerals were determined by the atomic absorption spectrometry (AAS) technique; (3) Results: Breast milk and infant formulas contained a full range of essential amino acids. In most cases, the content of individual amino acids and minerals decreased with increasing lactation. In infant formulas, there were higher contents of phenylalanine, glutamic acid, proline, serine, and tyrosine in follow-on milk (p < 0.05). The EAA/TAA ratio in breast milk and infant formulas was similar, but the milk differed in their qualitative composition. Infant formulas contained levels of individual minerals that were several times higher-especially Mg, Ca, Mn, and Fe.; (4) Conclusions: Colostrum is more concentrated, and the level of amino acids and minerals is higher in it; as the milk matures, it decreases. In most cases, the content of individual amino acids and minerals is higher in infant formulas than in human milk, which is established through strict Codex Alimentarius procedures to ensure the proper development of infants.

Protein and Immune Component Content of Donor Human Milk in Japan: Variation with Gestational and Postpartum Age

Donor human milk (DHM) is the second-best nutrition for preterm infants when their own mother's milk is unavailable. The nutrient content of human milk is influenced by various factors, including gestational and postpartum age, but there are no data regarding DHM composition in Japan. The aim of this study was to determine the protein and immune component content of DHM in Japan and to elucidate the effects of gestational and postpartum age on nutrient composition. From September 2021 to May 2022, 134 DHM samples were collected from 92 mothers of preterm and term infants. Protein concentrations in preterm DHM (n = 41) and term DHM (n = 93) were analyzed using a Miris Human Milk Analyzer. The concentrations of secretory immunoglobulin A (sIgA) and lactoferrin, major immune components, were measured using enzyme-linked immunosorbent assays. Preterm DHM exhibited higher protein content than term DHM (1.2 g/dL and 1.0 g/dL, respectively, p < 0.001), whereas sIgA content was higher in term DHM than in preterm DHM (110 μg/mL and 68.4 μg/mL, respectively, p < 0.001). Gestational age was negatively correlated with protein levels and positively correlated with sIgA and lactoferrin levels. Furthermore, a negative correlation was found between postpartum week and protein, sIgA, and lactoferrin concentrations. Our data suggest that gestational and postpartum age affects protein, sIgA, and lactoferrin concentrations in DHM. These results indicate the importance of nutritional analysis for the appropriate use of DHM in preterm infants.

Small Intestinal Microbiota Oscillations, Host Effects and Regulation-A Zoom into Three Key Effector Molecules

The gut microbiota features a unique diurnal rhythmicity which contributes to modulation of host physiology and homeostasis. The composition and activity of the microbiota and its secreted molecules influence the intestinal milieu and neighboring organs, such as the liver. Multiple immune-related molecules have been linked to the diurnal microbiota-host interaction, including Reg3γ, IgA, and MHCII, which are secreted or expressed on the gut surface and directly interact with intestinal bacteria. These molecules are also strongly influenced by dietary patterns, such as high-fat diet and time-restricted feeding, which are already known to modulate microbial rhythms and peripheral clocks. Herein, we use Reg3γ, IgA, and MHCII as test cases to highlight the divergent effects mediated by the diurnal activity of the gut microbiota and their downstream host effects. We further highlight current challenges and conflicts, remaining questions, and perspectives toward a holistic understanding of the microbiome's impacts on circadian human behavior.

Breast Milk and the Importance of Chrononutrition

During pregnancy the human fetus receives timed cues from the circadian rhythms of temperature, metabolites, and hormones from the mother. This influence is interrupted after parturition, the infant does not secrete melatonin and their circadian rhythms are still immature. However, evolution provided the solution to this problem. The newborn can continue receiving the mother's timed cues through breastmilk. Colostrum, transitional, and mature human milk are extraordinary complex biofluids that besides nutrients, contain an array of other non-nutritive components. Upon birth the first milk, colostrum, is rich in bioactive, immunological factors, and in complex oligosaccharides which help the proper establishment of the microbiome in the gut, which is crucial for the infants' health. Hormones, such as glucocorticoids and melatonin, transfer from the mother's plasma to milk, and then the infant is exposed to circadian cues from their mother. Also, milk components of fat, proteins, amino acids, and endogenous cannabinoids, among others, have a markedly different concentration between day and night. In the present review, we give an overview of nutritive and non-nutritive components and their daily rhythms in human milk and explore their physiological importance for the infant. Finally, we highlight some interventions with a circadian approach that emphasize the importance of circadian rhythms in the newborn for their survival, proper growth, and development. It is estimated that ~600,000 deaths/year are due to suboptimal breastfeeding. It is advisable to increase the rate of exclusive breastfeeding, during the day and night, as was established by the evolution of our species.

Evaluation of Breast Milk Macronutrient Content in Preeclamptic Mothers

Background: Preeclampsia remains among the leading causes of maternal and perinatal morbidity and mortality worldwide. This study aimed to evaluate the macronutrient content of colostrum in mothers with preeclampsia. Materials and Methods: Women who delivered by cesarean section at ≤37 weeks of gestation were included in the study. Fresh colostrum samples were collected by manual expression on postpartum days 2 and 4 and were analyzed using a mid-infrared human milk analyzer. Demographic characteristics of the patients were recorded. The protein, fat, carbohydrate, and energy composition of the milk samples were compared between mothers with and without preeclampsia. Results: A total of 58 colostrum samples (25 preeclampsia, 33 nonpreeclampsia) were analyzed. The median gestational age of the infants was similar in both groups (32 versus 33 weeks; p > 0.05). There were also no differences between the groups in terms of maternal age, maternal body mass index, maternal weight gain during pregnancy, and infant gender. Median protein, fat, and carbohydrate levels in the colostrum of the preeclamptic mothers were 2.2, 2.1, and 6.3 g/dL, respectively, compared with 1.8, 2.4, and 6.2 g/dL in the nonpreeclamptic mothers, respectively. Although the colostrum of preeclamptic mothers had higher protein content and lower fat content, the difference was not statistically significant. Carbohydrate and energy contents were similar in both groups. Conclusions: The presence of preeclampsia does not cause a significant change in the macronutrient composition of mother's milk. Analyses of micronutrients at different lactation stages in larger samples are needed.

What Are the Maternal Factors that Potentially Intervenes in the Nutritional Composition of Human Milk?

Background: To evaluate the potential factors associated with the nutritional composition of human milk of puerperal women. Methods: cross-sectional study, conducted between March 2016 and August 2017, with 107 women, selected in a Tertiary Health Care Tertiary Health Facility of the Unified Health System (SUS) in the Municipality of Rio de Janeiro. Data were collected two months after delivery. The dependent variable of the study was the nutritional composition of human milk. We divided the independent variables into hierarchical levels: distal (age, schooling, parity and pregestational nutritional status), intermediate (number of prenatal visits and gestational weight gain) and proximal (alcohol consumption, smoking, diabetes mellitus and hypertension). For data analysis, we applied the multiple linear regression, centered on the hierarchical model. Only the variables associated with the nutritional composition of breast milk remained in the final model at a 5% level of significance. Results: The nutritional composition of human milk yielded by women with pregestational overweight, smokers and hypertensive had higher amounts of lipids and energy. Conversely, women with gestational weight gain below the recommended had lower amounts of these components. Conclusion: The evaluation of factors associated with the nutritional composition of human milk is extremely important to assist post-partum care practices. In this study, we observed that lipid and energy contents were associated to pregestational nutritional status, gestational weight gain, smoking and hypertension.

Circadian Variation in Human Milk Composition, a Systematic Review

Background: Breastfeeding is considered the most optimal mode of feeding for neonates and mothers. Human milk changes over the course of lactation in order to perfectly suit the infant’s nutritional and immunological needs. Its composition also varies throughout the day. Circadian fluctuations in some bioactive components are suggested to transfer chronobiological information from mother to child to assist the development of the biological clock. This review aims to give a complete overview of studies examining human milk components found to exhibit circadian variation in their concentration. Methods: We included studies assessing the concentration of a specific human milk component more than once in 24 h. Study characteristics, including gestational age, lactational stage, sampling strategy, analytical method, and outcome were extracted. Methodological quality was graded using a modified Newcastle-Ottawa Scale (NOS). Results: A total of 83 reports assessing the circadian variation in the concentration of 71 human milk components were included. Heterogeneity among studies was high. The methodological quality varied widely. Significant circadian variation is found in tryptophan, fats, triacylglycerol, cholesterol, iron, melatonin, cortisol, and cortisone. This may play a role in the child’s growth and development in terms of the biological clock.

Do chronic noncommunicable diseases modify the macronutrient composition of human milk?

This study aims to evaluate the impact of excess body weight, diabetes mellitus, and hypertension on the nutritional composition of human milk. This cohort study was conducted at a tertiary public health unit in the city of Rio de Janeiro from March 2016 to February 2018. The data were collected in two stages (96 hours and one month after delivery). The macronutrients (carbohydrate, protein, lipid) and total energy were determined using the MIRIS^® equipment. The level of significance was 5%. Higher protein content was observed in the nutritional composition of colostrum in women with diabetes mellitus. A higher protein and energy content was observed in the milk of mothers with excessive body weight. The energy content was higher in the milk of mothers with excessive body weight. Increased protein content in the human milk of women with excessive body weight or diabetes.

MACRONUTRIENTS OF MOTHERS' MILK OF VERY LOW BIRTH WEIGHT INFANTS: ANALYSIS ACCORDING TO GESTATIONAL AGE AND MATERNAL VARIABLES

Objective:

To analyze the composition of macronutrients present in the milk of mothers of preterm newborn infants (PTNB) - protein, fat, carbohydrate, and calories - by gestational age (GA), chronological age (CA) and maternal variables.

Methods:

Longitudinal study that analyzed 215 milk samples from the 51 mothers of PTNB admitted in three Neonatal Intensive Care Units of Rio de Janeiro from May/2013-January/2014. Milk collection was performed by pickup pump, on a fixed day of each week until discharge. The spectrophotometric technique with Infrared Analysis (MilkoScan Minor 104) was used for the quantitative analysis. A sample of 7 mL of human milk was taken from the total volume of milk extracted by the mother. The data was grouped by GA (25-27, 28-31, 32-36, 37-40 weeks) and by CA (zero to 4, 5-8, 9-12, 13-16 weeks).

Results:

Protein, carbohydrate, fat and calories did not show any pattern of change, with no difference among groups of GA. When the macronutrients were analyzed by groups of CA, protein decreased, with significant difference between the first two groups of CA. Carbohydrates, fat and calories presented increasing values in all groups, without significant differences. Weight gain during pregnancy, maternal hypertension and maternal age were associated with changes in fat and calories in the first moment of the analysis of milk.

Conclusions:

There was a significant decrease in the levels of protein during the first eight weeks after birth. CA may be an important factor in the composition of human milk.

Circadian changes in the composition of human milk macronutrients depending on pregnancy duration: a cross-sectional study

Background

The purpose of this study was to evaluate the circadian variation of human milk macronutrients and energy content depending upon pregnancy duration.

Methods

One hundred eighty fresh human milk samples from 45 mothers (27 of preterm and 18 of full-term newborns) were collected on a single day chosen between the 14th to 16th day after delivery. The samples were taken four times per day at 12 PM, 6 PM, 12 AM and 6 AM. Only lactating women, who could not breastfeed their hospitalized newborns and expressed milk by breast pump, were enrolled in the study. Human milk macronutrient composition and energy count were evaluated by mid-infrared spectrophotometry.

Results

Significant differences in macronutrient content were observed between 6 AM and 12 PM for mean protein content (t = − 4.62, df = 44, p < 0.001), for mean fat content (t = − 2.10, df = 44, p = 0.04) and for mean energy content (t = − 2.24, df = 44, p = 0.03); between 6 AM and 6 PM for mean protein content (t = − 2.41, df = 43, p = 0.02), for mean fat content (t = − 3.76, df = 43, p = 0.001) and for mean energy content (t = − 3.85, df = 43, p < 0.001); between 12 PM and 12 AM for mean protein content (Wilcoxon test V = 75.5, p = 0.001), for mean fat content (t = 2.50, df = 44, p = 0.02) and for mean energy content (t = 2.74, df = 44, p = 0.01); between 6 PM and 12 AM for mean protein content (V = 229, p = 0.02), for mean fat content (t = 4.39, df = 43, p < 0.001) and for mean energy content (t = − 4.57, df = 43, p < 0.001). The average content of carbohydrates did not change significantly during the 24 h. The samples of preterm newborns’ mothers had more apparent diurnal fluctuations in macronutrient content.

Conclusions

Our study revealed significant diurnal variations in protein and fat in human milk, and these circadian fluctuations were more apparent in the milk of mothers of preterm infants.

The Impact of Dietary Fucosylated Oligosaccharides and Glycoproteins of Human Milk on Infant Well-Being

Apart from optimal nutritional value, human milk is the feeding strategy to support the immature immunological system of developing newborns and infants. The most beneficial dietary carbohydrate components of breast milk are human milk oligosaccharides (HMOs) and glycoproteins (HMGs), involved in both specific and nonspecific immunity. Fucosylated oligosaccharides represent the largest fraction of human milk oligosaccharides, with the simplest and the most abundant being 2'-fucosyllactose (2'FL). Fucosylated oligosaccharides, as well as glycans of glycoproteins, as beneficial dietary sugars, elicit anti-adhesive properties against fucose-dependent pathogens, and on the other hand are crucial for growth and metabolism of beneficial bacteria, and in this aspect participate in shaping a healthy microbiome. Well-documented secretor status related differences in the fucosylation profile of HMOs and HMGs may play a key but underestimated role in assessment of susceptibility to fucose-dependent pathogen infections, with a potential impact on applied clinical procedures. Nevertheless, due to genetic factors, about 20% of mothers do not provide their infants with beneficial dietary carbohydrates such as 2'-FL and other α1,2-fucosylated oligosaccharides and glycans of glycoproteins, despite breastfeeding them. The lack of such structures may have important implications for a wide range of aspects of infant well-being and healthcare. In light of the above, some artificial mixtures used in infant nutrition are supplemented with 2'-FL to more closely approximate the unique composition of maternal milk, including dietary-derived fucosylated oligosaccharides and glycoproteins.

Impact of pre-pregnancy excessive body weight on the composition of polyunsaturated fatty acids in breast milk: a systematic review

This study aims to identify through a systematic review the possible effects of pre-gestational excessive body weight on the composition of polyunsaturated fatty acids in human milk. The papers were selected in the following databases: PubMed, Virtual Health Library, EMBASE, Web of Science and SCOPUS. The search strategy employed descriptors: 'Human Milk' AND 'Obesity' OR 'Overweight' OR 'Body Mass Index' AND 'Fatty acid' OR 'Omega3' OR 'Omega6'. According to the established strategy, six manuscripts were selected. Most of the selected studies concluded that mothers with excessive body weight presented a milk with a higher concentration of omega 6. In addition, all selected studies identified an increased Omega-6/Omega-3 ratio in the milk of pre-gestational excessive body weight mothers compared to the eutrophic ones. The milk of pre-gestational excessive body weight women had a higher Omega-6/Omega-3 ratio, which confirms the importance of starting pregnancy with adequate weight, thus minimising the possible influences that excessive body weight can cause infant health.

Do maternal morbidities change the nutritional composition of human milk? A systematic review

This paper aims to identify the effects of maternal morbidities on the nutritional composition of human milk. This systematic review of the literature employed a PRISMA's protocol for searching, selecting, and extracting data. The flowchart proposed for bibliographic search resulted in 1,582 papers, of which 14 were selected for this work. The papers selected for this review were published between 1987 and 2016. Nine studies found significant differences in the nutritional composition of the milk of mothers with diabetes mellitus, arterial hypertension, or overweight compared to the control group. Most studies have shown that the presence of chronic diseases leads to changes in the nutritional composition of human milk. The main results showed a lower concentration of lactose and fat in the milk of women with diabetes mellitus. Concerning hypertension, higher levels of total protein were found in colostrum and mature milk. A higher fat and energy content was observed in overweight mothers. It is imperative that these women have continuous nutritional monitoring to minimize the impact of these morbidities on the nutritional composition of breast milk.

Overweight modifies the nutritional composition of human milk? A systematic review

This paper aims to identify the association between overweight and the nutritional composition of human milk. A systematic review was performed by searching on PubMed, Virtual Health Library (BVS), EMBASE, Web of Science, and SCOPUS databases, from May to June 2018, using keywords "Human Milk" AND "Overweight" OR "Obesity" OR "Body Mass Index". The bibliographic search returned 435 papers after the duplicates were removed. Of this total, 12 papers were selected for abstract reading, and nine works were incorporated into this systematic review. Eight papers showed that overweight increased the total concentration of lipids or glucose or macronutrient fractions, and only one study found no association between overweight and the nutritional composition of human milk. Most works selected evidenced that obesity changed the total concentration of lipids and their fractions. Thus, we recommend that women's weight and height be evaluated in the pregestational visit to identify and monitor nutritional deviations, contributing to weight adequacy before pregnancy and assisting in the production of milk with adequate nutritional composition.

Changes in the biochemical and immunological components of serum and colostrum of overweight and obese mothers

BACKGROUND

Obesity in pregnancy is associated with systemic inflammation, immunological changes and adverse maternal-fetal outcomes. Information on the association between maternal obesity and breast milk composition is scarce. This study describes changes and relationships between biochemical and immunological parameters of colostrum and serum of overweight and obese women.

METHODS

Colostrum and blood samples were collected from 25 normal weight, 24 overweight and 19 obese women for determination of glucose, total protein, triglycerides, cholesterol, immunoglobulins, complement proteins (C3 and C4), fat and calorie content and C-reactive protein (CRP).

RESULTS

Glucose was higher in colostrum of obese women (p = .002). In normal weight and obese women, total protein content was higher in colostrum than in serum (p = .001). Serum triglycerides (p = .008) and cholesterol (p = .010) concentrations were significantly higher in overweight and obese women than in their normal weight counterparts, but in colostrum their concentrations were similar across the three groups. Secretory IgA (sIgA) in colostrum and IgA in serum concentrations were significantly higher (p = .001) in overweight and obese mothers, whereas IgG and IgM concentrations did not vary among the groups (p = .825). Serum C3 (p = .001) and C4 (p = .040) concentrations were higher in obese women. No differences in colostrum complement proteins were detected among the groups. Calorie content (p = .003) and fat (p = .005) concentrations in colostrum and serum CRP (p = .002) were higher in obese women.

CONCLUSIONS

The results corroborate the hypothesis that colostrum of overweight and obese women undergoes biochemical and immunological changes that affect its composition, namely increasing glucose concentrations, calorie content, fat and sIgA concentrations.