Distribution of bioactive factors in human milk samples

The Effect of Holder Pasteurization and Different Variants on Breast Milk Antioxidants

BACKGROUND

After birth, breast milk (BM) is a known essential source of antioxidants for infants. We analyzed the non-enzymatic total antioxidant capacity (TAC), oxygen radical absorbance capacity (ORAC), and glutathione, calcium, transferrin, and total protein levels of human breast milk before and after Holder pasteurization (HoP).

METHODS

The collected donor BM samples were pasteurized with HoP.

RESULTS

HoP decreased TAC (-12.6%), ORAC (-12.1%), transferrin (-98.3%), and total protein (-21.4%) levels; HoP did not influence the glutathione concentration, and it increased the total calcium (+25.5%) concentration. Mothers who gave birth via Cesarean section had significantly lower TAC in their BM. TAC and glutathione levels were elevated in the BM of mothers over the age of 30. BM produced in the summer had higher glutathione and calcium levels compared to BM produced in the winter. The glutathione concentration in term milk samples was significantly higher in the first two months of lactation compared to the period between the third and sixth months. The transferrin level of BM for female infants was significantly higher than the BM for boys, and mothers with a BMI above 30 had increased transferrin in their samples.

CONCLUSIONS

Antioxidant levels in human milk are influenced by numerous factors. Environmental and maternal factors, the postpartum age at breast milk collection, and Holder pasteurization of the milk influence the antioxidant intake of the infant.

The contributions of parental lactation on offspring development: It's not udder nonsense!

The Developmental Origins of Health and Disease (DOHaD) hypothesis describes how maternal stress exposures experienced during critical periods of perinatal life are linked to altered developmental trajectories in offspring. Perinatal stress also induces changes in lactogenesis, milk volume, maternal care, and the nutritive and non-nutritive components of milk, affecting short and long-term developmental outcomes in offspring. For instance, selective early life stressors shape the contents of milk, including macro/micronutrients, immune components, microbiota, enzymes, hormones, milk-derived extracellular vesicles, and milk microRNAs. In this review, we highlight the contributions of parental lactation to offspring development by examining changes in the composition of breast milk in response to three well-characterized maternal stressors: nutritive stress, immune stress, and psychological stress. We discuss recent findings in human, animal, and in vitro models, their clinical relevance, study limitations, and potential therapeutic significance to improving human health and infant survival. We also discuss the benefits of enrichment methods and support tools that can be used to improve milk quality and volume as well as related developmental outcomes in offspring. Lastly, we use evidence-based primary literature to convey that even though select maternal stressors may modulate lactation biology (by influencing milk composition) depending on the severity and length of exposure, exclusive and/or prolonged milk feeding may attenuate the negative in utero effects of early life stressors and promote healthy developmental trajectories. Overall, scientific evidence supports lactation to be protective against nutritive and immune stressors, but the benefits of lactation in response to psychological stressors need further investigation.

Prevention of Chronic Morbidities in Extremely Premature Newborns with LISA-nCPAP Respiratory Therapy and Adjuvant Perinatal Strategies

Less invasive surfactant administration techniques, together with nasal continuous airway pressure (LISA-nCPAP) ventilation, an emerging noninvasive ventilation (NIV) technique in neonatology, are gaining more significance, even in extremely premature newborns (ELBW), under 27 weeks of gestational age. In this review, studies on LISA-nCPAP are compiled with an emphasis on short- and long-term morbidities associated with prematurity. Several perinatal preventative and therapeutic investigations are also discussed in order to start integrated therapies as numerous organ-saving techniques in addition to lung-protective ventilations. Two thirds of immature newborns can start their lives on NIV, and one third of them never need mechanical ventilation. With adjuvant intervention, these ratios are expected to be increased, resulting in better outcomes. Optimized cardiopulmonary transition, especially physiologic cord clamping, could have an additively beneficial effect on patient outcomes gained from NIV. Organ development and angiogenesis are strictly linked not only in the immature lung and retina, but also possibly in the kidney, and optimized interventions using angiogenic growth factors could lead to better morbidity-free survival. Corticosteroids, caffeine, insulin, thyroid hormones, antioxidants, N-acetylcysteine, and, moreover, the immunomodulatory components of mother's milk are also discussed as adjuvant treatments, since immature newborns deserve more complex neonatal interventions.

Insulin, Testosterone, and Albumin in Term and Preterm Breast Milk, Donor Milk, and Infant Formula

Background: Infants have three options for feeding: their own mother’s breast milk, donor milk, or infant formula. Insulin, testosterone, total protein, and albumin levels were measured in breast milk samples from the first 6 months of lactation, in donor milk samples, and in different infant formulas. Methods: Mothers who gave birth to term (n = 19) or preterm (n = 19) infants were recruited to collect breast milk samples during the first 6 months of lactation. The Breast Milk Collection Center (Unified Health Institution, Pécs, Hungary) provided 96 donor milk (DM) samples for analysis in our study. Insulin, testosterone, total protein, and albumin levels were measured in breast milk, donor milk, and infant formulas. Results: During the first 2 months of lactation, the concentration of insulin was lower (−27.4%) while the testosterone concentration was higher (+20.8%) compared to the period between the 3rd and 6th months only in the preterm breast milk samples. The infant formulas examined did not contain insulin or testosterone. Holder pasteurization (HoP) did not influence the level of testosterone in human milk, although HoP decreased the insulin (−53.6%) and albumin (−38.6%) concentrations. Conclusions: Diet impacts the hormone intake of infants, underlining the importance of breastfeeding and the possible supplementation of formula-fed infants.

New Strategies for Enhancement of Infant Milk Formulas Composition

This article covers the issues of remodeling breast milk’s protective properties during creating infant milk formulas. First of all, this concerns the conditions for normal intestinal microbiota development in growing organism. Its quantitative and qualitative features are the trigger of either sanogenetic, or pathological immune and metabolic reactions, and also determine gut-brain axis functioning. The protective significance of prebiotic composition diversity of mammalian milk and the inductive role of breast milk oligosaccharides are shown. The modern concept of synbiotics role in gastrointestinal tract and other systems functioning, as well as the use of modern synbiotics in the creation of infant formulas (available Russian formula included) are presented.

Annual and seasonal trends in cow's milk quality determined by FT-MIR spectroscopy in Hungary between 2011 and 2020

We analysed and monitored the major chemical composition of cow's bulk milk by Fourier transform mid-infrared (FT-MIR) spectroscopy over a 10-year period in the whole territory of Hungary. In addition, the two most important key parameters for milk quality assessment, total bacterial count (TBC) and somatic cell count (SCC) were also followed. Production parameters showed significant seasonal and yearly changes. The overall mean fat, protein, lactose and solids-non-fat (SNF) contents of cow's milk were 3.81%, 3.32%, 4.74% and 8.76%, respectively. A circannual variation was observed in the chemical composition and yield of milk components of samples examined between 2011 and 2020. Concerning milk fat, milk protein and SNF, the values were the lowest in summer and the highest in winter. In the case of lactose, the minimum values were measured in autumn and the maximum values in spring. An obvious trend of long-term elevation of lactose and SNF was found in the raw cow milk samples over the observed period. The overall mean TBC and SCC of cow's milk were 52 × 103 CFU ml-1 and 270 × 103 cells/ml, respectively. Although there were differences in the monthly average values, no seasonal cyclicality was observed.

[Influence of the coronavirus disease 2019 pandemic on maternal breastfeeding for very low birth weight infants]

OBJECTIVES

To investigate the changes in the rate and volume of mother's own milk (MOM) feeding for very low birth weight infants (VLBWIs) hospitalized during the prevention and control of the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

A retrospective analysis was performed on the medical data of the VLBWIs with a gestational age of <32 weeks who were born and admitted to the Neonatal Intensive Care Unit of Nanjing Maternal and Child Health Hospital from January 2019 to December 2020. The changes in the rate and volume of MOM feeding for VLBWIs during hospitalization were examined.

RESULTS

A total of 301 VLBWIs were enrolled. According to the timing of COVID-19 outbreak, these infants were divided into a pre-CIVID-19 group with 205 VLBWIs and a post-COVID-19 group with 96 VLBWIs. Compared with the pre-CIVID-19 group, the post-COVID-19 group had a significantly lower rate of MOM feeding within 28 days after birth and during hospitalization (P<0.05), a significantly lower volume of MOM feeding within 0-7 days, 0-14 days, and 0-28 days after birth (P<0.05), and significantly higher incidence rates of moderate-to-severe bronchopulmonary dysplasia and feeding intolerance (P<0.05).

CONCLUSIONS

The COVID-19 pandemic has a significant impact on MOM feeding for VLBWIs, and there are significant reductions in the rate and volume of MOM feeding for VLBWIs within 28 days after birth, as well as a significant reduction in the rate of MOM feeding during hospitalization.

Thyroxine and Thyroid-Stimulating Hormone in Own Mother’s Milk, Donor Milk, and Infant Formula

Breastfeeding is widely supported in clinical and home practices, and it is known that different forms of infant feeding differ in hormone content. Thyroid hormones have essential physiological roles. In our study, we examined thyroid-stimulating hormone (TSH), thyroxine, and albumin levels in breast milk produced for term (n = 16) or preterm (n = 15) infants throughout the first 6 months of lactation. Moreover, we analyzed these components in donor human milk and in three different infant formulas. Term and preterm breast milk samples were collected monthly. The two groups had similar levels of TSH (18.4 ± 1.4 vs. 24.7 ± 2.9 nU/L), but term milk contained higher amounts of thyroxine (11,245.5 ± 73.8 vs. 671.6 ± 61.2 nmol/L) during the examination period. The albumin level was significantly higher in preterm breast milk than in term breast milk (328.6 ± 17.1 vs. 264.2 ± 6.8 mg/L). In preterm breast milk we detected downward trends in the levels of TSH (−30.2%) and thyroxine (−29.2%) in the 3rd through 6th month compared to the first 2 months of lactation. Microbiological safety of donor milk was ensured by Holder pasteurization (HoP). From the Breast Milk Collection Center of Pécs, Hungary, we enrolled 44 donor mothers into the study. HoP decreased TSH (−73.8%), thyroxine (−22.4%), and albumin (−20.9%) concentrations. Infant formulas used by the Neonatal Intensive Care Unit of the University of Pécs were found to not contain the investigated hormones, but their albumin levels were similar to the breast milk samples. The present study shows the lack of thyroid hormones in infant formulas compared to human milk and raises the question of whether formula-fed infants should be supplemented with thyroid hormones.

Effect of sialyllactose on growth performance and intestinal epithelium functions in weaned pigs challenged by enterotoxigenic Escherichia Coli

Background

Sialyllactose (SL) is one of the most abundant oligosaccharides present in porcine breast milk. However, little is known about its effect on growth performance and intestinal health in weaned pigs. This study was conducted to explore the protective effect of SL on intestinal epithelium in weaned pigs upon enterotoxigenic Escherichia coli (ETEC) challenge.

Methods

Thirty-two pigs were randomly divided into four treatments. Pigs fed with a basal diet or basal diet containing SL (5.0 g/kg) were orally infused with ETEC or culture medium.

Results

SL supplementation elevated the average daily gain (ADG) and feed efficiency in the ETEC-challenged pigs (P < 0.05). SL also improved the digestibilities of dry matter (DM), gross energy (GE), and ash in non-challenged pigs (P < 0.05). Moreover, SL not only elevated serum concentrations of immunoglobulins (IgA, IgG, and IgM), but also significantly decreased the serum concentrations of inflammatory cytokines (TNF-α, IL-1β, and IL-6) upon ETEC challenge (P < 0.05). Interestingly, SL increased the villus height, the ratio of villus height to crypt depth (V:C), and the activities of mucosal sucrase and maltase in the jejunum and ileum (P < 0.05). SL also elevated the concentrations of microbial metabolites (e.g. acetic acid, propanoic acid, and butyric acid) and the abundance of Lactobacillus, Bifidobacterium, and Bacillus in the cecum (P < 0.05). Importantly, SL significantly elevated the expression levels of jejunal zonula occludins-1 (ZO-1), occluding, and fatty acid transport protein-4 (FATP4) in the ETEC-challenged pigs (P < 0.05).

Conclusions

SL can alleviate inflammation and intestinal injury in weaned pigs upon ETEC challenge, which was associated with suppressed secretion of inflammatory cytokines and elevated serum immunoglobulins, as well as improved intestinal epithelium functions and microbiota.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40104-022-00673-8.

Association between FADS Gene Expression and Polyunsaturated Fatty Acids in Breast Milk

Polyunsaturated fatty acid (PUFA) in breast milk provides physiological benefits for offspring and is closely related to endogenous biosynthesis in lactating women. Few studies have addressed the association between fatty acid desaturase (FADS) gene expression patterns and fatty acids in breast milk. This research aimed to explore the differences in PUFA levels among breast milk groups with different levels of FADS gene expression and provide a scientific basis for precision nutrition strategies. A total of 50 healthy women 42–45 days postpartum were included in this study. A basic information questionnaire and breast milk samples were collected. Eight types of PUFA were detected, and RNA was extracted from breast milk. The transcription level of the FADS gene was detected using real-time quantitative PCR. Significant differences in the content of gamma-linolenic acid and eicosatrienoic acid (C20:3n6) were found in breast milk among FADS1 gene transcription groups (p = 0.009, p = 0.042, respectively). No significant differences in PUFA were found among the FADS2 and FADS3 gene expression groups. The results demonstrated that n-6 PUFA was associated with the mRNA expression levels of the FADS1 gene. They are of great significance in developing new methods and diets to optimize infant feeding using breast milk.

Clinical Study on Plant Galactagogue Worldwide in Promoting Women's Lactation: a Scoping Review

Human milk is recommended by the World Health Organization (WHO) for the general well-being of infants. However, many mothers face an insufficient milk supply to breastfeed their children. Galactagogue, in particular, plant galactagogue, serves as a method to promote lactation. This in-depth review examines the evidence supporting different plants' galactagogic activity through clinical studies around the globe. A scoping review approach was adopted to establish the research questions, and define the findings, selection and analysis of the study. This scoping review highlights and compiles the clinical research performed globally involving plant galactagogue to better inform the medical practitioners, lactation consultants, nursing mothers, communities and relevant personnel on practicing, guidelines, policymaking and research. In general, a total of 1041 research publications were retrieved from different global bibliographic databases, of which only 13 articles were retained for analysis after applying the exclusion criteria. A total of 14 types of plants have undergone clinical studies in the past decade to verify their galactagogic activity. All but two showed a positive effect on promoting milk production. There were 42 articles categorised as excluded studies. The category includes review articles, surveys, case reports, introductory articles of regional plant galactagogue and preclinical studies, which involves animal testing and the studies exploring other issues related to plant galactagogue. The findings demonstrate that there is a significant research gap on the plant galactagogue using clinical studies. More clinical research is necessary to identify and verify the efficacy of various types of plant galactagogue for the benefit of humankind.

Administration of breast milk cell fractions to neonates with birthweight equal to or less than 1800 g: a randomized controlled trial

Background

Most premature and very low birthweight infants cannot tolerate breast milk feeding in the first few days of life and are deprived of its benefits. This study evaluates the clinical outcomes of administering breast milk cell fractions to neonates with a birthweight of ≤1800 g.

Methods

We conducted a randomized controlled trial on 156 infants in the neonatal intensive care unit of Mahdieh Maternity Hospital in Tehran, Iran, from May 2019 to April 2020. All neonates with a birthweight ≤1800 g were enrolled and divided into intervention and control groups using stratified block randomization. Neonates in the intervention group received the extracted breast milk cell fractions (BMCFs) of their own mother’s milk after being centrifuged in the first 6 to 12 h after birth. The control group received routine care, and breastfeeding was started as soon as tolerated in both groups. Study outcomes were necrotizing enterocolitis (NEC), death, and in-hospital complications.

Results

We divided participants into two groups: 75 neonates in the intervention group and 81 neonates in the control group. The mean birthweight of neonates was 1390.1 ± 314.4 g, and 19 (12.2%) neonates deceased during their in-hospital stay. The incidence of NEC was similar in both groups. After adjustment for possible confounders in the multivariable model, receiving BMCFs were independently associated with lower in-hospital mortality (5 [26.3%] vs. 70 (51.1%]; odds ratio (OR): 0.24; 95% confidence interval [CI] 0.07, 0.86). Also, in a subgroup analysis of neonates with birthweight less than 1500 g, in-hospital mortality was significantly lower in the intervention group (4 [9.5%] vs. 13 [30.2%]; OR: 0.24; 95% CI 0.07, 0.82). There were no differences in major complications such as bronchopulmonary dysplasia and retinopathy of prematurity between the two groups. No adverse effects occurred.

Conclusions

Our research demonstrated a significantly lower mortality rate in neonates (with a birthweight of ≤1800 g) who received breast milk cell fractions on the first day of life. Since this is a novel method with minimal intervention, we are looking forward to developing and evaluating this method in larger studies.

Trial registration

IIranian Registry of Clinical Trials. Registered 25 May 2019, IRCT20190228042868N1.

Comparison of the Characteristics of Breast Milk-derived Stem Cells with the Stem Cells Derived from the Other Sources: A Comparative Review

Breast milk (BrM) not only supplies nutrition, but it also contains a diverse population of cells. It has been estimated that up to 6% of the cells in human milk possess the characteristics of mesenchymal stem cells (MSC). Available data also indicate that these cells are multipotent and capable of self-renewal and differentiation with other cells. In this review, we have compared different characteristics, such as CD markers, differentiation capacity, and morphology of stem cells, derived from human breast milk (hBr-MSC) with human bone marrow (hBMSC), Wharton's jelly (WJMSC), and human adipose tissue (hADMSC). Through the literature review, it was revealed that human breast milk-derived stem cells specifically express a group of cell surface markers, including CD14, CD31, CD45, and CD86. Importantly, a group of markers, CD13, CD29, CD44, CD105, CD106, CD146, and CD166, were identified, which were common in the four sources of stem cells. WJMSC, hBMSC, hADMSC, and hBr-MSC are potently able to differentiate into the mesoderm, ectoderm, and endoderm cell lineages. The ability of hBr-MSCs todifferentiate into the neural stem cells, neurons, adipocyte, hepatocyte, chondrocyte, osteocyte, and cardiomyocytes has made these cells a promising source of stem cells in regenerative medicine, while isolation of stem cells from the commonly used sources, such as bone marrow, requires invasive procedures. Although autologous breast milk-derived stem cells are an accessible source for women who are in the lactation period, breast milk can be considered as a source of stem cells with high differentiation potential without any ethical concern.

Anti-Infective, Anti-Inflammatory, and Immunomodulatory Properties of Breast Milk Factors for the Protection of Infants in the Pandemic From COVID-19

COVID-19 pandemic since the end of 2019 spreads worldwide, counting millions of victims. The viral invasion, systemic inflammation, and consequent organ failure are the gravest features of coronavirus disease 2019 (COVID-19), and they are associated with a high mortality rate. The aim of this study is to evaluate the role of breast milk in the COVID-19 pandemic, analyzing its antiviral, anti-inflammatory, and immunoregulatory effects due to its bioactive components, so numerous and important for the protection of infants. The study tried to demonstrate that all the components of human milk are capable of performing functions on all the pathogenic events recognized and described in COVID-19 disease. Those human milk factors are well-tolerated and practically free of side effects, so breast milk should become a research topic to discover therapies even in this epidemic. In the first part, the mechanisms of protection and defense of the breast milk elements will be delineated; in the second section, it will describe the human milk effects in viral infections and it will be hypothesized how the known mechanisms could act in COVID infection.

Breast Milk for Term and Preterm Infants-Own Mother's Milk or Donor Milk?

Hormones are important biological regulators, controlling development and physiological processes throughout life. We investigated pituitary hormones such as follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and total protein levels during the first 6 months of lactation. Breast milk samples were collected every fourth week of lactation from mothers who gave birth to preterm (n = 14) or term (n = 16) infants. Donor milk is suggested when own mother’s milk is not available; therefore, we collected breast milk samples before and after Holder pasteurization (HoP) from the Breast Milk Collection Center of Pécs, Hungary. Three infant formulas prepared in the Neonatal Intensive Care Unit of the University of Pécs were tested at three different time points. Our aim was to examine the hormone content of own mother’s milk and donor milk. There were no significant changes over time in the concentrations of any hormone. Preterm milk had higher PRL (28.2 ± 2.5 vs. 19.3 ± 2.3 ng/mL) and LH (36.3 ± 8.8 vs. 15.9 ± 4.1 mIU/L) concentrations than term milk during the first 6 months of lactation. Total protein and FSH concentrations did not differ between preterm and term breast milk. Holder pasteurization decreased the PRL concentration (30.4 ± 1.8 vs. 14.4 ± 0.6 ng/mL) and did not affect gonadotropin levels of donor milk. Infant formulas have higher total protein content than breast milk but do not contain detectable levels of pituitary hormones. Differences were detected in the content of pituitary hormones produced for preterm and term infants. Divergence between feeding options offers opportunities for improvement of nutritional guidelines for both hospital and home feeding practices.

Hormone levels in preterm and donor human milk before and after Holder pasteurization

BACKGROUND

After birth, breastfeeding is the exclusive source of hormonal signaling between mother and infant. Hospitalized infants often receive donor milk when their own mother's milk is unavailable.

METHODS

The presence of insulin, leptin, cortisol, progesterone, and testosterone was examined in samples from milk bank donors and mothers of preterm infants. We further investigated the effect of Holder pasteurization (HoP) on hormone levels.

RESULTS

Comparing nonpasteurized samples, leptin levels were nearly threefold higher in milk from mothers of preterm infants versus donated milk, and regardless of milk source, leptin levels were significantly decreased by HoP. Insulin concentrations were also decreased by HoP, and among mothers of preterm infants, obesity was associated with significantly higher content of leptin and insulin. While combined use of donor milk and HoP was associated with cortisol levels nearly threefold higher than those in nonpasteurized own mother's milk, progesterone and testosterone content did not differ by source or pasteurization.

CONCLUSIONS

The hormonal composition of breast milk is impacted by HoP and maternal obesity. Compared to nonpasteurized maternal milk, use of pasteurized donor milk dramatically decreases the intake of leptin while increasing the intake of cortisol. Further research is necessary to define optimal breast milk processing practices.

More than sugar in the milk: human milk oligosaccharides as essential bioactive molecules in breast milk and current insight in beneficial effects

Human milk is the gold standard for newborn infants. Breast milk not only provides nutrients, it also contains bioactive components that guide the development of the infant's intestinal immune system, which can have a lifelong effect. The bioactive molecules in breast milk regulate microbiota development, immune maturation and gut barrier function. Human milk oligosaccharides (hMOs) are the most abundant bioactive molecules in human milk and have multiple beneficial functions such as support of growth of beneficial bacteria, anti-pathogenic effects, immune modulating effects, and stimulation of intestine barrier functions. Here we critically review the current insight into the benefits of bioactive molecules in mother milk that contribute to neonatal development and focus on current knowledge of hMO-functions on microbiota and the gastrointestinal immune barrier. hMOs produced via genetically engineered microorganisms are now applied in infant formulas to mimic the nutritional composition of breast milk as closely as possible, and their prospects and scientific challenges are discussed in depth.

Breast Milk, a Source of Beneficial Microbes and Associated Benefits for Infant Health

Human breast milk is considered the optimum feeding regime for newborn infants due to its ability to provide complete nutrition and many bioactive health factors. Breast feeding is associated with improved infant health and immune development, less incidences of gastrointestinal disease and lower mortality rates than formula fed infants. As well as providing fundamental nutrients to the growing infant, breast milk is a source of commensal bacteria which further enhance infant health by preventing pathogen adhesion and promoting gut colonisation of beneficial microbes. While breast milk was initially considered a sterile fluid and microbes isolated were considered contaminants, it is now widely accepted that breast milk is home to its own unique microbiome. The origins of bacteria in breast milk have been subject to much debate, however, the possibility of an entero-mammary pathway allowing for transfer of microbes from maternal gut to the mammary gland is one potential pathway. Human milk derived strains can be regarded as potential probiotics; therefore, many studies have focused on isolating strains from milk for subsequent use in infant health and nutrition markets. This review aims to discuss mammary gland development in preparation for lactation as well as explore the microbial composition and origins of the human milk microbiota with a focus on probiotic development.

Pituitary Glycoprotein Hormones in Human Milk before and after Pasteurization or Refrigeration

Our aims were to investigate the presence of pituitary glycoprotein hormones in preterm and donor milk, and to examine the effects of Holder pasteurization and refrigeration on the levels of these hormones. We measured follicle-stimulating hormone (FSH), luteinizing hormone (LH), and thyroid-stimulating hormone (TSH) in milk samples from mothers who delivered prematurely (n = 27) and in samples of mothers who delivered at term and donated milk to the Mother's Milk Bank of Iowa (n = 30). The gonadotropins and TSH were present in similar amounts within human milk produced for preterm and term infants. FSH increased 21% after refrigeration (p < 0.05), while LH declined by 39% (p < 0.05). Holder pasteurization decreased LH by 24% (p < 0.05) and increased TSH by 17% (p < 0.05). Holder pasteurization followed by refrigeration resulted in a 21% increase in FSH and a 41% decrease in LH (both p < 0.05), resulting in more than a 3-fold increase in donor milk FSH:LH ratios (p < 0.05 versus fresh donor milk). Despite structural similarities, the gonadotropins are differentially impacted by Holder pasteurization and refrigeration, and this results in marked alterations in the relative amount of FSH and LH that may be administered to preterm infants, potentially swinging hormonal balance towards ovarian hyperstimulation in females and hypogonadism in males.

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.