Adipokines in breast milk and preterm infants

The Effects of Breastfeeding and Gestational Diabetes Mellitus on Body Mass Composition and the Levels of Selected Hormones after Childbirth

Breastfeeding may have a positive effect on glucose metabolism and insulin sensitivity, which may reduce the risk of developing diabetes following gestational diabetes mellitus (GDM). This study aimed to evaluate the effect of breastfeeding and GDM on the body mass composition of the studied women, the levels of leptin, ghrelin, adiponectin, resistin, and insulin, and weight loss during the 6-8-week postpartum period and 1 year after childbirth.

MATERIALS AND METHODS

The study group included 42 women with a singleton pregnancy, diagnosed with GDM between the 24th and 28th week of gestation. The control group consisted of 28 non-diabetic women with a singleton pregnancy. This study was carried out at 6-8 weeks as well as at 1 year postpartum. The women were subjected to body weight measurements and body composition analysis performed using a professional body composition analyzer TANITA DC-430 S MA. Waist circumference and subcutaneous fat was measured. Blood for laboratory tests was taken in the morning, on an empty stomach.

RESULTS

It was shown that, regardless of diabetes, exclusive breastfeeding had a significant impact on weight loss at 6-8 weeks postpartum (p = 0.014785) and lower insulin levels (p = 0.047). However, there was no effect of breastfeeding on the women's anthropometric measurements or hormone levels one year after delivery, except for the thickness of subcutaneous adipose tissue, which was significantly lower in breastfeeding women (p = 0.03). One year after delivery, breastfeeding women had a lower BMI (p = 0.0014), less-thick subcutaneous adipose tissue (p < 0.001), and a lower risk of obesity (p = 0.016). There were also higher insulin and ghrelin levels in both breastfeeding and non-breastfeeding women (p < 0.001), and lower resistin levels in non-breastfeeding women (p = 0.004). Women who had diabetes during pregnancy had a significantly reduced waist circumference and subcutaneous fat thickness after one year (p < 0.001 and p = 0.05, respectively).

CONCLUSIONS

Having diabetes during pregnancy did not significantly affect the results of anthropometric measurements and hormone levels noted at 6-8 weeks after delivery (the only exception was the thickness of subcutaneous fat tissue, which was greater in women without GDM). This may indicate normalization of carbohydrate metabolism after childbirth; however, the observation period is too short to elucidate long-term metabolic effects. This suggests the need for further research related to GDM and breastfeeding.

Postnatal Leptin Levels Correlate with Breast Milk Leptin Content in Infants Born before 32 Weeks Gestation

Perinatal leptin deficiency and reduced intake of mother’s milk may contribute to the development of childhood obesity. Preterm infants have reduced leptin production, and they are at heightened risk of neonatal leptin deficiency. Because fresh human milk contains significantly more leptin than donor milk, we used a cross-over design to determine if blood leptin levels in maternal milk-fed preterm infants fall during conversion to donor human milk. Infants born between 22 0/7 and 31 6/7 weeks gestation on exclusive maternal milk feedings were enrolled into a 21-day cross-over trial. On days 1−7 and 15−21, infants were fed maternal milk, and on days 8−14, infants were fed donor milk. On day 1, study infants had a mean postmenstrual age of 33 weeks. Plasma leptin correlated with milk leptin, and leptin levels in maternal milk far exceed the leptin levels of donor milk. Plasma leptin did not increase during donor milk administration, but it did following resumption of maternal milk (p < 0.05). In this crossover trial, preterm infant blood leptin levels correlated with milk leptin content. This suggests that preterm infants can enterally absorb leptin from human milk, and leptin-rich breast milk may be a targeted therapy for the prevention of obesity.

Birth weight and breastfeeding are differentially associated with physical fitness components

BACKGROUND/OBJECTIVES

The study purpose was to assess the impact of birth weight and breastfeeding duration on physical fitness components.

SUBJECTS/METHODS

Study participants were 985 adolescents boys and 1246 girls (12.5-17.5 years) participating in the HELENA study. Standardised physical fitness procedures included: cardio-respiratory fitness, flexibility, upper body muscular strength, and lower body explosive strength. Birth weight and breastfeeding duration were assessed by parents' questionnaire. Associations between neonatal data and physical fitness were investigated using linear mixed models.

RESULTS

Significant associations between body muscular strength, and breastfeeding duration were observed in the unadjusted analyses for boys. When adjusting for potential confounding factors (z-score body mass index, fat-free mass, fat mass), only lower body muscular strength, by standing broad jump-a proxy measure of muscular explosivity- was positively associated with breastfeeding duration. Furthermore, significant associations were observed between upper body muscular strength (by hand grip),-a proxy measure of muscular power-in boys as well as in girls.

CONCLUSIONS

Birth weight and breastfeeding duration have different effects on muscular strength components. The present results suggest that birth weight positively influences the development of muscular power, while breastfeeding duration positively influences muscular explosivity.

Human Milk Metabolic Hormones: Analytical Methods and Current Understanding

Human milk (HM) contains a wide array of peptide hormones including leptin and adiponectin, which are involved in the regulation of infant growth and development. These essential hormones might play an important role in the regulation of metabolic reprogramming of the new-born infant. However, HM hormone studies are sparse and heterogeneous in regard to the study design, sample collection, preparation and analysis methods. This review discussed the limitations of HM hormone analysis highlighting the gaps in pre-analytical and analytical stages. The methods used to quantify HM metabolic hormones (leptin, adiponectin, ghrelin, insulin, obestatin, resistin and apelin) can be classified as immunoassay, immunosensor and chromatography. Immunoassay methods (ELISA and RIA) have been predominantly used in the measurement of these HM hormones. The relative validity parameters of HM hormones analysis are often overlooked in publications, despite the complexity and differences of HM matrix when compared to that of plasma and urine. Therefore, appropriate reports of validation parameters of methodology and instrumentation are crucial for accurate measurements and therefore better understanding of the HM metabolic hormones and their influences on infant outcomes.

Growth Factor Concentrations in Human Milk Are Associated With Infant Weight and BMI From Birth to 5 Years

Background: Human milk bioactives may play a role in infant health and development. Although the variability in their concentrations in milk is well-established, the impact of differential milk profiles on infant growth outcomes remains unclear. Thus, the aim of the present study was to investigate whether different concentrations of metabolic hormones are associated with different weight and BMI in infants beyond the first year of life. Methods: Milk samples at 2.6 (±0.4) months after birth and anthropometric measures at 13 months, 2, 3, and 5 years were collected as part of the Finnish STEPS cohort study from 501 mothers and the respective 507 infants. Leptin, adiponectin, insulin-like growth factor (IGF)-1 and cyclic glycine-proline (cGP) in milk were analyzed. Multiple regression models and a repeated measures mixed model were used to examine associations between milk hormone concentrations and weight and BMI z-scores across time, at each time-point, and weight gain from birth to each follow-up visit. All models were corrected for birth weight, infant sex, duration of exclusive and total breastfeeding, time of introduction of solid foods and maternal pre-pregnancy BMI. Results: Higher milk IGF-1 was associated with higher weight at 13 months (p = 0.004) but lower weight at 3 (p = 0.011) and 5 years of age (p = 0.049). Higher cGP was associated with lower weight across the 5 years (p = 0.019) but with higher BMI at 5 years (p = 0.021). Leptin and adiponectin did not display associations with infant growth at this time. Sex interactions were also absent. Conclusions: Our results suggest that the interplay between human milk-borne IGF-1 and cGP is similar to that reported in other mammals and may have an important role in defining infant growth trajectories beyond the first year of life. Further research should explore the determinants and origins of these milk-borne compounds and evaluate their effect on infant growth and metabolism.

Early-life programming of adipose tissue

Worldwide obesity is increasing at an alarming rate in children and adolescents, with the consequent emergence of co-morbidities. Moreover, the maternal environment during pregnancy plays an important role in obesity, contributing to transgenerational transmission of the same and metabolic dysfunction. White adipose tissue represents a prime target of metabolic programming induced by maternal milieu. In this article, we review adipose tissue physiology and development, as well as maternal influences during the perinatal period that may lead to obesity in early postnatal life and adulthood. First, we describe the adipose tissue cell composition, distribution and hormonal action, together with the evidence of hormonal factors participating in fetal/postnatal programming. Subsequently, we describe the critical periods of adipose tissue development and the relationship of gestational and early postnatal life with healthy fetal adipose tissue expansion. Furthermore, we discuss the evidence showing that adipose tissue is an important target for nutritional, hormonal and epigenetic signals to modulate fetal growth. Finally, we describe nutritional, hormonal, epigenetic and microbiome changes observed in maternal obesity, and whether their disruption alters fetal growth and adiposity. The presented evidence supports the developmental origins of health and disease concept, which proposes that the homeostatic system is affected during gestational and postnatal development, impeding the ability to regulate body weight after birth, thereby resulting in adult obesity. Consequently, we anticipate that promoting a healthy early-life programming of adipose tissue and increasing the knowledge of the mechanisms by which maternal factors affect the health of future generations may offer novel strategies for explaining and addressing worldwide health problems such as obesity.

Premature Birth Infants Present Elevated Inflammatory Markers in the Meconium

Introduction: Prematurity, a well-established risk factor for various intestinal diseases in newborns, results in increased morbidity and mortality. However, the intestinal inflammatory status of preterm (PT) infants has been poorly characterized. Here we have broadly described the intestinal and systemic inflammatory status of PT children. Materials and Methods: Meconium and plasma from 39 PT and 32 full term (T) newborns were studied. Fecal calprotectin, polymorphonuclear leukocyte elastase (PMN-E), TNF, IL-17A, IL-8, IP-10, MCP-1, MIP-1, IL-1β, IL-1α, and E-selectin and the enzymatic activities of myeloperoxidase (MPO) and alkaline phosphatase (AP) in meconium were measured. Plasma levels of AP, hepatocyte growth factor, nerve growth factor (NGF), proinflammatory cytokines, leptin, adiponectin, PAI-1, and resistin were also determined. Correlations with gestational age (GA) and birth weight (BW) were studied. Results: Neutrophil derived PMN-E, MPO and calprotectin were increased in the meconium of PT compared to T newborns, while AP was decreased. No significant differences were found in other inflammatory parameters. Considering data from all children, GA and BW showed inverse correlation with neutrophil markers, while AP directly correlated with BW. Plasma levels of IL-1β and NGF were enhanced in PT infants, and were also negatively correlated with BW. PT children additionally showed neutropenia and decreased adiponectin, leptin, haematocrit, and haemoglobin. These parameters (neutrophils, adiponectin, and so forth) were positively correlated with GA and BW, while IL-8, MCP-1, PAI-1, and plasma AP were negatively correlated. PT children showing postnatal morbidity exhibited increased meconium MPO and MIP-1α. Conclusion: PT neonates present a significant elevation of intestinal inflammatory parameters, characterized by the presence of neutrophil markers, associated with mild systemic inflammation.

A Review of Bioactive Factors in Human Breastmilk: A Focus on Prematurity

Preterm birth is an increasing worldwide problem. Prematurity is the second most common cause of death in children under 5 years of age. It is associated with a higher risk of several pathologies in the perinatal period and adulthood. Maternal milk, a complex fluid with several bioactive factors, is the best option for the newborn. Its dynamic composition is influenced by diverse factors such as maternal age, lactation period, and health status. The aim of the present review is to summarize the current knowledge regarding some bioactive factors present in breastmilk, namely antioxidants, growth factors, adipokines, and cytokines, paying specific attention to prematurity. The revised literature reveals that the highest levels of these bioactive factors are found in the colostrum and they decrease along the lactation period; bioactive factors are found in higher levels in preterm as compared to full-term milk, they are lacking in formula milk, and decreased in donated milk. However, there are still some gaps and inconclusive data, and further research in this field is needed. Given the fact that many preterm mothers are unable to complete breastfeeding, new information could be important to develop infant supplements that best match preterm human milk.

New Achievements in High-Pressure Processing to Preserve Human Milk Bioactivity

High-pressure processing (HPP) is a non-thermal technology that is being increasingly applied in food industries worldwide. It was proposed that this method could be used as an alternative to holder pasteurization (HoP; 62.5°C, 30 min) in milk banks but its impact on the immunologic, enzymatic and hormonal components of human milk has not yet been evaluated in detail. The aim of our study was to compare the effects of HPP in variants: (1) 600 MPa, 10 min (2) 100 MPa, 10 min, interval 10 min, 600 MPa, 10 min (3) 200 MPa, 10 min, interval 10 min, 400 MPa, 10 min (4) 200 MPa, 10 min, interval 10 min, 600 MPa, 10 min in temperature range 19-21°C and HoP on the leptin, adiponectin, insulin, hepatocyte growth factor (HGF), lactoferrin and IgG contents in human milk. HoP was done at the Regional Human Milk Bank in Warsaw at the Holy Family Hospital on S90 Eco pasteurizer (Sterifeed, Medicare Colgate Ltd). Apparatus U4000/65 (Unipress Equipment, Poland) was used for pascalization. Milk samples were obtained from women during 2-6 weeks of lactation. Post-treatment culture showed no endogenous bacterial contamination in any tested option. Concentrations of selected components were determined using ELISA tests. The level of all analyzed components were significantly decreased by HoP: leptin 77.86%, adiponectin 32.79%, insulin 32.40%, HGF 88.72%, lactoferrin 60.31@.%, IgG 49.04%. All HPP variants caused an increase in leptin concentration, respectively (1) 81.79% (2) 90.01% (3) 86.12% (4) 47.96%. Retention of insulin after HPP was (1) 88.20% (2) 81.98% (3) 94.76% (4) 90.31% HGF (1) 36.15% (2) 38.81% 97.15% (3) 97.15% (4) 43.02%, lactoferrin (1) 55.78% (2) 57.63% (3) 78.77% (4) 64.75%. Moreover, HPP variant as 200 + 400 MPa preserved IgG (82.24%) better than HoP and resulted not statistically significant change of adiponectin level (38.55%) compare to raw milk. Our results showed that HPP leads to preservation of adipokines, growth factor, and lactoferrin, IgG much better or comparable with HoP.

Are breast milk adipokines affected by maternal dietary factors?

Background Maternal diet and gestational age of infant may affect the composition of breast milk. The aim of this study was to evaluate the relationship between breast milk adiponectin and leptin levels of mothers delivering preterm and term infants and maternal diet. Methods Sixty-five mothers (31 preterm, 34 term) were included in the study. General information about parents and infants and food consumption of mothers were determined through a questionnaire. Milk samples were taken from mothers during the period between the 15th and 30th day after birth (mature milk). For the evaluation of maternal diet, the nutrient adequacy ratio (NAR) and mean adequacy ratio (MAR) were used. Results According to MAR, 71.0% of preterm mothers' and 79.4% of term mothers' dietary adequacy was categorized as "good", and none of the mothers fell into the "insufficient" category (p>0.05). The median (interquartile range [IQR]) level of adipokines was found to be higher in preterm than in term mothers (24.6 [14.3] ng/mL; 22.9 [9.7] ng/mL for adiponectin and 2.0 [2.5] ng/mL; 0.0 [2.3] ng/mL for leptin, respectively) (p>0.05). A negative correlation was found between the leptin level and intake of unsaturated fatty acids, protein NAR and meat, poultry and fish consumption in preterm mothers (p<0.05). A positive correlation was found between leptin concentration and MAR, protein, calcium, potassium NAR and consumption of dairy products in term mothers (p<0.05). In the regression model, gestational age and MAR are important predictors of leptin. Conclusions These results show that maternal diet is related to the leptin content in breast milk.

Effect of Breastfeeding in Early Life on Cardiorespiratory and Physical Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Numerous studies have reported the associations between the type of feeding during infancy and subsequent chronic diseases.

OBJECTIVE

The objective of this systematic review is to synthesize the available literature concerning the effect of breastfeeding in infancy on physical and cardiorespiratory fitness in children and adolescents.

MATERIALS AND METHODS

We performed a comprehensive search of medical bibliographic databases to identify observational studies reporting the association between breastfeeding and cardiorespiratory or physical fitness. Random effects model was used for calculating the pooled estimates.

RESULTS

Three studies with 2,792 children were included in the meta-analysis. The mean value of VO₂max was similar between formula-fed and 1-3 months breastfed participants (standardized mean difference [SMD]: 0.1, 95% confidence intervals [CI]: -0.09 to 0.29, p = 0.31). There was no difference between 3 and 6 months breastfed (SMD: 0.17, 95% CI: -0.01 to 0.35, p = 0.06), >6 months breastfed (SMD: 0.37, 95% CI: -0.03 to 0.78, p = 0.07), and formula-fed children. The pooled SMD in handgrip strength was 0.09 (95% CI: -0.04 to 0.23; p = 0.17) between 1 and 3 months breastfed and formula-fed children .Nevertheless, 3-6 months (SMD: 0.13; 95% CI: 0.03-0.24) and >6 months (SMD: 0.19; 95% CI: 0.01-0.37) breastfeeding was associated with higher handgrip strength compared with formula-fed children. Breastfeeding for 1-3 (SMD: 0.20; 95% CI: 0.12-0.28), 3-6 (SMD: 0.27; 95% CI: 0.18-0.37), and >6 months (SMD: 0.34; 95% CI: 0.11-0.58) led to a significantly higher standing long-jump performance compared with formula feeding.

CONCLUSIONS

Breastfeeding shows beneficial effects on physical fitness, but further well-designed studies need to clarify effects of breastfeeding on cardiorespiratory fitness.

Maternal and Infantile Adiponectin as Marker for Anthropometric Parameters of Lactating Mothers and their Breast-Fed Infants

BACKGROUND

Breast milk adiponectin could play a role in the regulation of infants' growth during lactation.

AIM OF WORK

The aim is to evaluate adiponectin concentration in human milk and to investigate its relationship with serum adiponectin concentration in lactating mothers and their breastfed infants and with anthropometric parameters of infants and mothers.

MATERIALS AND METHODS

Sixty healthy term infants and their healthy lactating mothers are included at infant age of 1 month then repeated again at the age of 4 months. All subjects included in this study were subjected to history, clinical examination, investigations including serum level of adiponectin of infants and their mothers by RIA test, human milk level of adiponectin by ELISA test.

RESULTS

There was a significant decrease in serum adiponectin of infant and mothers and maternal breast milk at the age of 4 months when compared to them at the age of 1 month. There was a significant positive correlation between infant serum adiponection, maternal serum adiponectin and breast milk adiponectin at infant's age of 1 month and at infant's age of 4 months. There was a significant negative correlation between maternal serum adiponectin and BMI of mothers. There was a significant negative correlation between infant serum adiponectin and their weight and length of infants at the age of 1 month and at the age of 4 months.

CONCLUSIONS

There's a metabolic link between mothers and their infants through breast milk during the first 6 months of life. A gradual decline in adiponectin level in maternal breast milk is associated with a gradual increase in infant growth up to 6 months of age.

Association of maternal breast milk and serum levels of macronutrients, hormones, and maternal body composition with infant's body weight

BACKGROUND/OBJECTIVES

This study was aimed to investigate the association of maternal serum and breast-milk levels of macronutrients, hormones, growth factors, and maternal body composition with infant's body weight.

SUBJECTS/METHODS

Eighty mother-infant pairs comprised 40 with overweight or obese infant and 40 with normal-weight infant were enrolled in this study. The level of ghrelin, Leptin, adiponectin, EGF, and IGF1 in plasma and breast milk were assessed. Daily breast milk intake and macronutrient concentration along with anthropometric indices of mother-infant pairs were also assessed.

RESULTS

No significant differences were observed in concentrations of serum hormones between two groups (p > 0.05). However, hormones levels in maternal serum were higher than those in breast milk. A significant positive correlation was found between serum EGF and ghrelin (r = 0.57, p = 0 < 0001). Higher IGF1 in serum showed a significant association with its milk counterpart (r = 0.37). Current mother's weight was associated with infant's weight at the 2nd and 6th month (B = 0.023 p = 0.04, B = 0.055 p = 0.005). The breast-milk macronutrient content was not comparable between two groups. However, the average daily breast milk consumption in obese infants was higher than normals (p = 0.001). Milk EGF and leptin were related to a decrease of 59% and 46% the odds of obese infant development, respectively. There was a significant association of milk EGF and ghrelin with birth weight (B = -0.19, p = 0.04 and B = -0.2, p = 0.04, respectively), and also serum leptin with infant's body weight at the 6th month.

CONCLUSIONS

Our findings provide a positive association of maternal weight, daily breast milk intake, EGF, and ghrelin with infant's body weight.

Adipokines played a limited role in predicting temporary growth differences between very low birthweight infants with and without bronchopulmonary dysplasia

AIMS

This study explored whether growth was poorer among very low birthweight (VLBW) infants with bronchopulmonary dysplasia (BPD) and assessed adipokine levels as predictors of early growth.

METHODS

We studied 53 VLBW infants born in Tampere University Hospital up to 12 months of corrected age (CA). The median gestational age of the 21 infants with BPD and 32 infants without BPD was 29 weeks, and the median birthweights were 930 (635-1470) and 1185 (650-1470) grams. Growth parameters, macronutrients intake and plasma levels of adipokines were measured.

RESULTS

Bronchopulmonary dysplasia infants were lighter than controls until 36 weeks of CA, with catch-up growth achieved by three months of CA. Adipsin levels were lower in BPD infants at 28 days of postnatal age. High leptin levels seemed protective for low weight for height at nine months of CA. The duration of ventilator therapy predicted low weight for height, length for age and body mass index and BPD predicted low length for age at 12 months of CA.

CONCLUSIONS

Catch-up growth in VLBW infants with BPD was achieved by three months of CA, but adipokines played a limited role in predicting growth. Shortening ventilator therapy could help growth in VLBW infants.

The concentrations of adipokines in goat milk: relation to plasma levels, inflammatory status, milk quality and composition

The main objectives of our study were to measure the major adipokines adiponectin, leptin and resistin in goat milk, to assess their interrelationships and to assess their relationships with the plasma and serum concentrations of total protein, cholesterol, total lipids, plasma C-reactive protein (CRP), milk somatic cell count (SCC), milk total aerobic colony and lactobacillus count, and milk components in lactating Saanen goats. The study was performed on eighteen lactating Saanen goats. Milk and blood samples were collected on days 20, 35, 50, 65 and 80 of lactation postpartum. The milk and plasma adiponectin levels on days 50, 65 and 80 postpartum were significantly higher than those on day 20. The milk and plasma leptin levels were lower on day 20 than on days 35, 50, 65 and 80. The milk concentrations of these major adipokines were positively intercorrelated. The milk and plasma concentrations of these three adipokines were also positively correlated. The plasma CRP concentrations correlated positively with milk leptin and resistin concentrations and inversely with milk adiponectin concentration. Milk adiponectin concentration was inversely related with its SCC. These data confirm that adiponectin, leptin and resistin are present in goat milk. The milk concentrations of these three adipokines were interrelated and interacted with the general inflammatory marker, CRP. The inverse relationship between milk adiponectin concentrations and its SCC suggests that variations in milk adiponectin might be involved in the udder health of lactating goats, but clinical trials are needed to support this hypothesis.

Associations between exclusive breastfeeding and physical fitness during childhood

PURPOSE

Exposure to breastfeeding improves the survival, health, and development of children; therefore, breast milk is recommended as the exclusive nutrient source for feeding term infants during the first 6 months. This cross-sectional study aimed to determine the possible association between exposure to exclusive breastfeeding and physical fitness performance in children and, if so, whether this association is influenced by the breastfeeding duration.

METHODS

A total of 2853 (52.3 % girls) European children from the IDEFICS study aged 6-11 years with complete data on physical fitness (cardiorespiratory fitness, muscular strength, flexibility, balance, speed) and exclusive breastfeeding duration (never, 1-3, 4-6, 7-12 months) were included in the present study. Multivariate and mixed linear regression models were estimated and adjusted for sex, age, birth weight, diet, physical activity, body mass index, and parental factors (age, body mass index, educational attainment).

RESULTS

We found a positive association between exclusive breastfeeding and lower-body explosive strength (β = 0.034) as well as flexibility (β = 0.028). We also found a positive association between breastfeeding and balance in boys (β = 0.039), while this association was negative in girls (β = -0.029). To improve lower-body explosive strength, 1-3 months of exclusive breastfeeding were enough; a longer duration did not lead to increasing benefit. In contrast, 4-6 months of breastfeeding were necessary to have any benefit on flexibility or balance, although this became nonsignificant after adjustment for body mass index and physical activity.

CONCLUSIONS

Exclusive breastfeeding seems a natural way of slightly improving some physical fitness components (mainly lower-body muscle strength) and thus future health.

Bioactive factors in milk across lactation: Maternal effects and influence on infant growth in rhesus macaques (Macaca mulatta)

Among mammals, numerous bioactive factors in milk vary across mothers and influence offspring outcomes. This emerging area of research has primarily investigated such dynamics within rodent biomedical models, domesticated dairy breeds, and among humans in clinical contexts. Less understood are signaling factors in the milk of non-human primates. Here, we report on multiple bioactive components in rhesus macaque (Macaca mulatta) milk and their associations with maternal and infant characteristics. Milk samples were collected from 59 macaques at multiple time points across lactation in conjunction with maternal and infant morphometrics and life-history animal records. Milk was assayed for adiponectin (APN), epidermal growth factor (EGF) and its receptor (EGF-R), and transforming growth factor beta 2 (TGF-β2 ). Regression models were constructed to assess the contributions of maternal factors on variation in milk bioactives, and on the relationship of this variation to infant body mass and growth. Maternal body mass, parity, social rank, and infant sex were all predictive of concentrations of milk bioactives. Primiparous mothers produced milk with higher adiponectin, but lower EGF, than multiparous mothers. Heavier mothers produced milk with lower EGF and EGF-R, but higher TGF-β2 . Mothers of daughters produced milk with higher TGF-β2 . Mid-ranking mothers produced milk with higher mean EGF and adiponectin concentrations than low-ranking mothers. Milk EGF and EGF-R were positively associated with infant body mass and growth rate. Importantly, these signaling bioactives (APN, EGF, EGF-R, and TGF-β2 ) were significantly correlated with nutritional values of milk. The effects of milk signals remained after controlling for the available energy in milk revealing the added physiological role of non-nutritive milk bioactives in the developing infant. Integrating analyses of energetic and other bioactive components of milk yields an important perspective for interpreting the magnitude, sources, and consequences of inter-individual variation in milk synthesis. Am. J. Primatol. 78:838-850, 2016. © 2016 Wiley Periodicals, Inc.

Effect of maternal body mass index on hormones in breast milk: a systematic review

Background

Maternal Body Mass Index (BMI) is positively associated with infant obesity risk. Breast milk contains a number of hormones that may influence infant metabolism during the neonatal period; these may have additional downstream effects on infant appetite regulatory pathways, thereby influencing propensity towards obesity in later life.

Objective

To conduct a systematic review of studies examining the association between maternal BMI and the concentration of appetite-regulating hormones in breast milk.

Method

Pubmed was searched for studies reporting the association between maternal BMI and leptin, adiponectin, insulin, ghrelin, resistin, obestatin, Peptide YY and Glucagon-Like Peptide 1 in breast milk.

Results

Twenty six studies were identified and included in the systematic review. There was a high degree of variability between studies with regard to collection, preparation and analysis of breast milk samples. Eleven of fifteen studies reporting breast milk leptin found a positive association between maternal BMI and milk leptin concentration. Two of nine studies investigating adiponectin found an association between maternal BMI and breast milk adiponectin concentration; however significance was lost in one study following adjustment for time post-partum. No association was seen between maternal BMI and milk adiponectin in the other seven studies identified. Evidence for an association between other appetite regulating hormones and maternal BMI was either inconclusive, or lacking.

Conclusions

A positive association between maternal BMI and breast milk leptin concentration is consistently found in most studies, despite variable methodology. Evidence for such an association with breast milk adiponectin concentration, however, is lacking with additional research needed for other hormones including insulin, ghrelin, resistin, obestatin, peptide YY and glucagon-like peptide-1. As most current studies have been conducted with small sample sizes, future studies should ensure adequate sample sizes and standardized methodology.

Adipokines in breast milk: an update

Epidemiological surveys indicate that nutrition in infancy is implicated in the long-term tendency to obesity and that a longer duration of breastfeeding is associated with a protective effect against metabolic disorders later in life. However, the precise cause of this association is not well understood. Recent studies on the compounds present in human breast milk have identified various adipokines, including leptin, adiponectin, resistin, obestatin, nesfatin, ghrelin and apelins. Some of these compounds are involved in the regulation of food intake and energy balance. The presence of these adipokines in breast milk suggests that they may be responsible for the regulation of growth in early infancy and that they could influence the energy balance and development of metabolic disorders in childhood and adulthood.

Maternal regulation of offspring development in mammals is an ancient adaptation tied to lactation

The developmental origins of health and disease (DOHaD) is a paradigm for understanding metabolic diseases of modern humans. Vulnerability to disease is linked to perturbations in development during critical time periods in fetal and neonatal life. These perturbations are caused by environmental signals, often generated or transduced by the mother. The regulation of mammalian development depends to a large extent on maternal biochemical signals to her offspring. We argue that this adaptation is ancient, and originated with the evolution of lactation. Lactation evolved earlier than live birth and before the extensive placental development of modern eutherian mammals. Milk contains a host of signaling molecules including nutrients, immunoglobulins, growth factors and metabolic hormones. As evidenced by marsupials, lactation originally served to supply the biochemical factors for growth and development for what is essentially a fetus to a weanling transitioning to independent existence. In placental mammals maternal signaling in earliest life is accomplished through the maternal-placental-fetal connection, with more of development shifted to in utero life. However, significant development occurs postpartum, supported by milk. Mothers of all taxa provide biochemical signals to their offspring, but for non-mammalian mothers the time window is short. Developing mammals receive maternal biochemical signals over an extended period. These signals serve to guide normal development, but also can vary in response to environmental conditions. The ancient adaptation of lactation resulted in a lineage (mammals) in which maternal regulation of offspring development evolved to a heightened degree, with the ability to modify development at multiple time points. Modern metabolic diseases may arise due to a mismatch between maternal regulation and eventual circumstances of the offspring, and due to a large proportion of mothers that exceed past evolutionary norms in body fat and pregnancy weight gain such that maternal signals may no longer be within the adaptive range.

Changes in plasma adipokines in prepubertal children with a history of extrauterine growth restriction

OBJECTIVE

Because nutritional support in perinatal life has been associated with metabolic programming, children with a history of extrauterine growth restriction (EUGR) might display alterations in the adipocyte and in the secretion of adipokines. The aim of this study was to assess adiponectin, resistin, and leptin concentrations in prepubertal children with a history of EUGR, and to determine the potential correlation between these adipokines and metabolic parameters.

METHODS

This case-control study sample included 38 prepubertal children with a history of EUGR and a control group of 123 healthy children of similar age and sex. Anthropometric measures and blood pressure were assessed. Biochemical markers and blood adipokine concentrations (adiponectin, resistin, and leptin) were evaluated.

RESULTS

Adiponectin concentration was significantly lower in the EUGR group compared with controls (EUGR: 11.49 ± 6.07 versus control: 25.72 ± 10.13 μg/mL), and resistin concentration was higher (EUGR: 20332.95 ± 6401.25 versus control: 8056.31 ± 3823.63 pg/mL), even after adjustment for gestational age, weight, and size at birth. Systolic blood pressure was associated with adipokines concentrations in the EUGR group (P < 0.001). In EUGR children adiponectin was associated with high-density lipoprotein cholesterol (P = 0.042), whereas resistin was associated with carbohydrate metabolism parameters (P < 0.001).

CONCLUSIONS

Early postnatal malnutrition in EUGR children could program adipose tissue. Plasma adipokines can be measured in childhood to identify precocious changes that may be associated with a higher risk for metabolic syndrome or cardiovascular disease later in life.

Presence and dynamics of leptin, GLP-1, and PYY in human breast milk at early postpartum

OBJECTIVE

The presence of appetite hormones, namely glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and leptin in breast milk may be important in infant feeding regulation and infant growth. This study evaluated whether concentrations of GLP-1, PYY, and leptin change across a single feeding (from fore- to hindmilk), and are associated with maternal and infant anthropometrics.

DESIGN AND METHODS

Thirteen postpartum women (mean ± SD: 25.6 ± 4.5 years, 72.0 ± 11.9 kg) provided fore- and hindmilk samples 4-5 weeks after delivery and underwent measurements of body weight and composition by Dual X-ray Absorptiometry. GLP-1, PYY, and leptin concentrations were measured using radioimmunoassay, and milk fat content was determined by creamatocrit.

RESULTS

Concentration of GLP-1 and content of milk fat was higher in hindmilk than foremilk (P ≤ 0.05). PYY and leptin concentrations did not change between fore- and hindmilk. Both leptin concentration and milk fat content were correlated with indices of maternal adiposity, including body mass index (r = 0.65-0.85, P < 0.02), and fat mass (r = 0.65-0.84, P < 0.02). Hindmilk GLP-1 was correlated with infant weight gain from birth to 6 months (r = -0.67, P = 0.034).

CONCLUSION

The presence of appetite hormones in breast milk may be important in infant appetite and growth regulation.

Adiponectin in breast milk: relation to serum adiponectin concentration in lactating mothers and their infants

AIMS

  The aims of the study were to determine human breast milk adiponectin concentration and to investigate its relationship with serum adiponectin concentration in lactating mothers and their infants and also to evaluate the relationship between serum adiponectin concentration and anthropometric parameters in nurses and infants.

METHODS

  We enrolled 60 healthy term breastfed (BF) infants and their lactating mothers. Adiponectin was determined by radioimmunoassay test in serum and by enzyme-linked immunosorbent assay test in human milk (HM). Infants' and mothers' anthropometric parameters were measured.

RESULTS

  Median (25‰, 75‰) adiponectin concentration in HM was 9.99 (3.59, 20.52) ng/mL. Serum adiponectin concentration in infants was 60.49 (45.76, 74.24) μg/mL and in lactating mothers 21.14 (12.61, 29.66) μg/mL. Adiponectin concentration in HM correlated positively with adiponectin in mothers' serum; r = 0.60 (p < 0.001) and in infants' serum r = 0.37 (p = 0.015). Adiponectin in HM correlated negatively with infants' age r = -0.3 (p = 0.04). Infants' serum adiponectin correlated negatively with their weight r = -0.35 (p = 0.005), length r = -0.35 (p = 0.006) and age r = -0.46 (p < 0.001) and mothers' serum adiponectin with their weight r = -0.37 (p = 0.02) and body mass index r = -0.45 (p = 0.004).

CONCLUSIONS

  The observed correlations between adiponectin in mothers, HM and BF infants may be suggestive for a metabolic link between nurses and infants through milk.

An Infantile Case of Transient, Severe Hypercholesterolemia with Normalization after Complete Weaning from Breast-feeding

A 20-d-old boy was referred to our department because of hyperthyrotropinemia at neonatal mass screening and diagnosed with neonatal transient hyperthyrotropinemia. A follow-up examination when the patient was 5 mo old revealed severe hypercholesterolemia. Familial hypercholesterolemia was first suspected because of the patient’s significantly high levels of total and low-density lipoprotein cholesterol. The parent’s serum lipid profiles were examined and found to be normal. He was completely breast-fed until 6 mo of age. Breast milk was still the main source of food for a period following weaning. At 14 mo old, the patient was weaned completely from breast milk, and his serum cholesterol levels decreased dramatically. According to the normal lipid profiles of the patient’s parents and the spontaneous normalization of serum cholesterol levels after complete weaning from breast milk, breast-feeding was suggested to be responsible for his transient severe hypercholesterolemia. It is well documented that breast-fed infants have higher serum cholesterol levels than formula-fed infants. However, there is no reported case with severe hypercholesterolemia equivalent to or higher than the levels observed in the case of familial hypercholesterolemia. Although the exact mechanism is unknown, it is necessary to consider that a small number of cases develop severe hypercholesterolemia related to breast-feeding.

Ghrelin and feeding behaviour in preterm infants

The importance of early life events in the development of metabolic diseases is well recognized. Early postnatal environment, including nutrition, is key to future health, and this is particularly true for preterm infants. It is important that these infants receive sufficient nutrients to prevent growth restriction and promote neurodevelopment, while minimizing predisposition to metabolic diseases later in life. Feeding habits are the fundamental elements of nutrition and are influenced by many factors, including personal and familial habits, socioeconomic status, and cultural environment. In the last decades, there has been an important scientific interest toward the comprehension of the molecular and neural mechanisms regulating appetite. In these networks, act many peptide hormones produced in brain or gut, among which ghrelin is important because of its action in the short-term regulation of food intake and the long-term regulation of body weight. Ghrelin stimulates appetite and plays a role in regulating feeding behaviour. Ghrelin levels vary from fetal life through to early adulthood, with the highest levels observed in the very early years. Cord ghrelin levels have been evaluated in term and preterm newborns and high ghrelin levels have been observed in small-for-gestational age newborns and in newborns with intrauterine growth restriction. Moreover, ghrelin has been detected in term and preterm human breast milk, suggesting that it may play a role in the development of neuroendocrine pathways regulating appetite and energy homeostasis in early life. However, more research is required to better define ghrelin's role in breast milk and on feeding behaviour.

Serum levels of leptin, adiponectin and resistin are interrelated and related to total antioxidant capacity, free fatty acids and phospholipids in early neonatal life

OBJECTIVES

The aims of this study were to determine interrelationships between serum leptin, adiponectin and resistin, insulin-like growth factor-1 (IGF-1), total antioxidant capacity (TAC), non-esterified fatty acids (NEFA) and phospholipids concentrations in infants.

DESIGN AND METHODS

A cross-sectional study was conducted to assess serum levels of leptin, adiponectin, resistin, IGF-1, TAC, NEFA and phospholipids in 45 breast-fed infants enrolled at 4-30 days after birth.

RESULTS

Serum leptin and adiponectin concentrations were positively correlated. Serum resistin concentrations were inversely correlated to serum leptin and adiponectin concentrations. Serum TAC was positively correlated to serum leptin and adiponectin, and inversely to serum resistin concentrations. Serum adiponectin concentrations were positively related to serum NEFA and phospholipid concentrations. Serum resistin concentrations were inversely related to serum NEFA, and phospholipid concentrations.

CONCLUSION

These data show that circulatory levels of leptin, adiponectin and resistin are interrelated and they apparently interact with the anti-oxidant system of infants.

Babies fed breastmilk by breast versus by bottle: a pilot study evaluating early growth patterns

BACKGROUND

Numerous studies have documented short- and long-term differences in growth and body composition based on whether an infant is breastfed or formula-fed. However, little is known about whether these differences result from the substance consumed (breastmilk vs. formula) or from the delivery method (breast vs. bottle). This prospective pilot study compared the growth and body composition patterns of 19 predominantly breastfed/nursing infants (NG) and 18 infants fed significant quantities of breastmilk by bottle (BG) during the first 6 months of life.

METHODS

Infants were measured in a laboratory setting each month by trained staff. Growth measures (length, weight, and head circumference) were compared to World Health Organization growth standards. Body composition, including relative fat mass (%FM), was measured using an air-displacement plethysmography system (Pea Pod(®), Life Measurement, Inc., Concord, CA).

RESULTS

With the exception of small differences in length and weight scaled for length (body mass index and weight-for-length z-score) present at birth and continuing for the first 1-2 months of life, NG and BG infants were similar in weight, weight-for-age z-scores, head circumference, fat mass, and %FM. However, BG infants were three times more likely to exceed the 85(th) percentile for weight velocity during the 4-6-month age interval than NG infants (33% vs. 10%, respectively), but this did not reach statistical significance in this sample size (p = 0.12).

CONCLUSIONS

This pilot study suggests the delivery method (breast vs. bottle) for breastmilk may not dramatically affect growth for the first 4 months of life; however, future research with larger samples will be needed to carefully evaluate longer-term growth patterns in infants fed breastmilk by bottle.

Leptin determination in colostrum and early human milk from mothers of preterm and term infants

BACKGROUND

Leptin is involved in the regulation of food intake and energy expenditure and is therefore important for growth and brain development. Analytical methods used for leptin measurement in human milk differ widely in the literature and yield varying results.

AIMS

To compare different preparation methods for the analysis of leptin in human milk and to investigate the leptin levels in colostrum and mature human milk from mothers of preterm or term infants.

METHODS

Mothers delivering a preterm (n=37) or a term infant (n=40) were recruited for a prospective study and were ask to collect breast milk on the 3rd and 28th day of lactation. Leptin, protein and fat concentrations were analysed. Clinical data of mother and child were recorded prospectively.

RESULTS

Skim milk was most appropriate for leptin analysis. Human milk leptin concentrations did not differ between preterm and term human milk. In term milk, leptin concentration on day 28 was lower than on day 3 (p<0.05). Milk leptin levels on the 3rd and 28th day were positively correlated with mothers' body mass index, but not with fat content in milk.

CONCLUSION

Skim milk was the most stabile preparation for leptin analysis. Preterm and term human milk contain leptin in equal concentrations. Human milk leptin depends on mothers' body mass index.

The presence of the peptides apelin, ghrelin and nesfatin-1 in the human breast milk, and the lowering of their levels in patients with gestational diabetes mellitus

Numerous bioactive peptides (such as ghrelins) have been identified in breast milk but there is no information concerning apelin and nesfatin-1. Therefore, present study was designated to explore whether breast milk contains apelin and nesfatin-1, to determine the concentrations and to compare these with serum levels. In addition, the concentrations of these peptides were compared in patients with gestational diabetes and normal lactating samples. Furthermore, this study explored the effectivity of various commercial diagnostic kits for determining ghrelin concentrations in breast milk. Ten gestational diabetic lactating women (29.1±2.2 years old and BMI: 33.2±4.8) and 10 control lactating women (28.2±1.8 years old and BMI: 39.48±1.7) were enrolled in the study. An ELISA was used to determine concentrations of apelin-36 and -12, nesfatin-1, and acylated and desacylated ghrelin in serum, colostrum and mature milk. Serum apelin-36 and -12 concentrations were correlated with colostrum and mature milk, and the same trends were observed for nesfatin-1. Apelins and nesfatin-1 concentrations were higher in mature milk than in colostrum (P<0.05). The concentration of apelins, ghrelins and nesfatin-1 in serum and milk in gestational diabetic lactating women was lower than in control samples. The majority of ghrelin circulating and in milk was the free form (desacylated) in both groups of women. This is the first report to describe the presence of apelins and nesfatin-1 in breast milk. It is suggested that the source of ghrelins, apelins and nesfatin-1 in breast milk is likely to be breast tissue (autonomous production). These bioactive peptides found in breast milk could be important for growth, energy regulation and maturation of the gastrointestinal system in neonates.