Increased Exclusivity of Breastfeeding Associated with Reduced Gut Inflammation in Infants

Postnatal supplementation with alarmins S100a8/a9 ameliorates malnutrition-induced neonate enteropathy in mice

Malnutrition is linked to 45% of global childhood mortality, however, the impact of maternal malnutrition on the child's health remains elusive. Previous studies suggested that maternal malnutrition does not affect breast milk composition. Yet, malnourished children often develop a so-called environmental enteropathy, assumed to be triggered by frequent pathogen uptake and unfavorable gut colonization. Here, we show in a murine model that maternal malnutrition induces a persistent inflammatory gut dysfunction in the offspring that establishes during nursing and does not recover after weaning onto standard diet. Early intestinal influx of neutrophils, impaired postnatal development of gut-regulatory functions, and expansion of Enterobacteriaceae were hallmarks of this enteropathy. This gut phenotype resembled those developing under deficient S100a8/a9-supply via breast milk, which is a known key factor for the postnatal development of gut homeostasis. We could confirm that S100a8/a9 is lacking in the breast milk of malnourished mothers and the offspring's intestine. Nutritional supply of S100a8 to neonates of malnourished mothers abrogated the aberrant development of gut mucosal immunity and microbiota colonization and protected them lifelong against severe enteric infections and non-infectious bowel diseases. S100a8 supplementation after birth might be a promising measure to counteract deleterious imprinting of gut immunity by maternal malnutrition.

Cardiometabolic effects of breastfeeding on infants of diabetic mothers

BACKGROUND

Breast milk is the best and principal nutritional source for neonates and infants. It may protect infants against many metabolic diseases, predominantly obesity and type 2 diabetes. Diabetes mellitus (DM) is a chronic metabolic and microvascular disease that affects all the body systems and all ages from intrauterine life to late adulthood. Breastfeeding protects against infant mortality and diseases, such as necrotizing enterocolitis, diarrhoea, respiratory infections, viral and bacterial infection, eczema, allergic rhinitis, asthma, food allergies, malocclusion, dental caries, Crohn's disease, and ulcerative colitis. It also protects against obesity and insulin resistance and increases intelligence and mental development. Gestational diabetes has short and long-term impacts on infants of diabetic mothers (IDM). Breast milk composition changes in mothers with gestational diabetes.

AIM

To investigate the beneficial or detrimental effects of breastfeeding on the cardiometabolic health of IDM and their mothers.

METHODS

We performed a database search on different engines and a thorough literature review and included 121 research published in English between January 2000 and December 15, 2022, in this review.

RESULTS

Most of the literature agreed on the beneficial effects of breast milk for both the mother and the infant in the short and long terms. Breastfeeding protects mothers with gestational diabetes against obesity and type 2 DM. Despite some evidence of the protective effects of breastfeeding on IDM in the short and long term, the evidence is not strong enough due to the presence of many confounding factors and a lack of sufficient studies.

CONCLUSION

We need more comprehensive research to prove these effects. Despite many obstacles that may enface mothers with gestational diabetes to start and maintain breastfeeding, every effort should be made to encourage them to breastfeed.

Association between maternal antibiotic exposure during pregnancy and childhood obesity in the Japan Environment and Children's Study

BACKGROUND

The association between maternal antibiotic exposure during pregnancy and childhood obesity is still unclear.

OBJECTIVES

The study aimed to evaluate the association between prenatal exposure to antibiotics and obesity at age 3 years using data from a large Japanese birth cohort.

METHODS

The Japan Environment and Children's Study is a nationwide birth cohort study. In this study, singleton vaginal full-term births were included. Obesity was defined as body mass index ≥95th percentile according to child growth standards. Prenatal antibiotic exposure was defined as antimicrobial agent use during pregnancy and was collected from maternal interviews and medical record transcripts. Logistic regression analysis was performed to evaluate the association of prenatal antibiotic exposure with child obesity at 3 years.

RESULTS

In the crude and adjusted models with all children, maternal antibiotic exposure during pregnancy showed a marginal relationship with child obesity at 3 years. In the analyses according to exposure period and sex, exposure to antibiotics during the second/third trimester was significantly associated with obesity at the age of 3 years in female infants, but not in male infants, although the exposure during the first trimester was not in both sexes.

CONCLUSION

Maternal antibiotic exposure during mid/late pregnancy may result in child obesity.

Cessation of exclusive breastfeeding and seasonality, but not small intestinal bacterial overgrowth, are associated with environmental enteric dysfunction: A birth cohort study amongst infants in rural Kenya

Background

Environmental Enteric Dysfunction (EED) is a chronic intestinal inflammatory disorder of unclear aetiology prevalent amongst children in low-income settings and associated with stunting. We aimed to characterise development of EED and its putative risk factors amongst rural Kenyan infants.

Methods

In a birth cohort study in Junju, rural coastal Kenya, between August 2015 and January 2017, 100 infants were each followed for nine months. Breastfeeding status was recorded weekly and anthropometry monthly. Acute illnesses and antibiotics were captured by active and passive surveillance. Intestinal function and small intestinal bacterial overgrowth (SIBO) were assessed by monthly urinary lactulose mannitol (LM) and breath hydrogen tests. Faecal alpha-1-antitrypsin, myeloperoxidase and neopterin were measured as EED biomarkers, and microbiota composition assessed by 16S sequencing.

Findings

Twenty nine of the 88 participants (33%) that underwent length measurement at nine months of age were stunted (length-for-age Z score <-2). During the rainy season, linear growth was slower and LM ratio was higher. In multivariable models, LM ratio, myeloperoxidase and neopterin increased after cessation of continuous-since-birth exclusive breastfeeding. For LM ratio this only occurred during the rainy season. EED markers were not associated with antibiotics, acute illnesses, SIBO, or gut microbiota diversity. Microbiota diversified with age and was not strongly associated with complementary food introduction or linear growth impairment.

Interpretation

Our data suggest that intensified promotion of uninterrupted exclusive breastfeeding amongst infants under six months during the rainy season, where rainfall is seasonal, may help prevent EED. Our findings also suggest that therapeutic strategies directed towards SIBO are unlikely to impact on EED in this setting. However, further development of non-invasive diagnostic methods for SIBO is required.

Funding

This research was funded in part by the Wellcome Trust (Research Training Fellowship to RJC (103376/Z/13/Z)). EPKP was supported by the MRC/DfID Newton Fund (MR/N006259/1). JAB was supported by the MRC/DFiD/Wellcome Trust Joint Global Health Trials scheme (MR/M007367/1) and the Bill & Melinda Gates Foundation (OPP1131320). HHU was supported by the NIHR Oxford Biomedical Research Centre (IS-BRC-1215-20008).

Breastfeeding and circulating immunological markers during the first 3 years of life: the DIABIMMUNE study

AIMS/HYPOTHESIS

Our aim was to study the association between duration of breastfeeding and circulating immunological markers during the first 3 years of life in children with HLA-conferred susceptibility to type 1 diabetes.

METHODS

We performed a longitudinal analysis of 38 circulating immunological markers (cytokines, chemokines and growth factors) in serum samples from Finnish (56 individuals, 147 samples), Estonian (56 individuals 148 samples) and Russian Karelian children (62 individuals, 149 samples) at 3, 6, 12, 18, 24 and 36 months of age. We also analysed gut inflammation markers (calprotectin and human β defensin-2) at 3 (n = 96) and 6 months (n = 153) of age. Comparisons of immunological marker medians were performed between children who were breastfed for 6 months or longer vs children who were breastfed for less than 6 months.

RESULTS

Breastfeeding for 6 months or longer vs less than 6 months was associated with lower median of serum immunological markers at 6 months (granulocyte-macrophage colony-stimulating factor [GMCSF], macrophage inflammatory protein [MIP-3α]), 12 months (IFN-α2, vascular endothelial growth factor, GMCSF, IFN-γ, IL-21), 18 months (FGF-2, IFN-α2) and 24 months of age (CCL11 [eotaxin], monocyte chemoattractant protein-1, TGFα, soluble CD40 ligand, IL-13, IL-21, IL-5, MIP-1α) (all p < 0.01) but not at 36 months of age. Breastfeeding was not associated with gut inflammation markers at 3 and 6 months of age.

CONCLUSIONS/INTERPRETATION

Children who were breastfed for 6 months or longer had lower medians for 14 immunological markers at one or more age points during the first 2 years of life compared with children who were breastfed for less than 6 months. The clinical meaning of the findings is not clear. However, the present study contributes to the understanding of immunological differences in children that have been breastfed longer, and thus provides a mechanistic suggestion for the previously observed associations between breastfeeding and risk of type 1 diabetes.

The risk of infectious pathogens in breast-feeding, donated human milk and breast milk substitutes

OBJECTIVE

This review collates the published reports that focus on microbial and viral illnesses that can be transmitted by breast milk, donor milk and powdered infant formula (PIF). In this context, we attempt to define a risk framework encompassing those hazards, exposure scenarios, vulnerability and protective factors.

DESIGN

A literature search was performed for reported cases of morbidity and mortality associated with different infant feeding modes.

SETTING

Exclusive breast-feeding is the recommended for infant feeding under 6 months, or failing that, provision of donated human milk. However, the use of PIF remains high despite its intrinsic and extrinsic risk of microbial contamination, as well as the potential for adverse physiological effects, including infant gut dysbiosis.

RESULTS

Viable pathogen transmission via breast-feeding or donor milk (pasteurised and unpasteurised) is rare. However, transmission of HIV and human T-cell lymphotropic virus-1 is a concern for breast-feeding mothers, particularly for mothers undertaking a mixed feeding mode (PIF and breast-feeding). In PIF, intrinsic and extrinsic microbial contamination, such as Cronobacter and Salmonella, remain significant identifiable causes of infant morbidity and mortality.

CONCLUSIONS

Disease transmission through breast-feeding or donor human milk is rare, most likely owing to its complex intrinsically protective composition of human milk and protection of the infant gut lining. Contamination of PIF and the morbidity associated with this is likely underappreciated in terms of community risk. A better system of safe donor milk sharing that also establishes security of supply for non-hospitalised healthy infants in need of breast milk would reduce the reliance on PIF.

Immunologic Properties of Human Milk and Clinical Implications in the Neonatal Population

Human milk contains various bioactive substances including hormones, immunoglobulins, enzymes, and growth factors in addition to its macro- and micronutrients. It has been suggested that human milk is a vehicle of communication between the maternal and infant immune systems, providing passive protection as well as direct active immunomodulation. Human milk protects newborns against pathogens by acting directly on multiple physiologic systems. Bioactive and immunologic factors regulate the infant's immune, metabolic, and microbiome systems. Breastfeeding protects infants in all socioeconomic groups, showing a pattern of protective dose/duration-response effects. This review summarizes the immune components and immunologic properties of human milk and provides an update of their potential implications in the neonatal population.

Protective Effect of Breastfeeding on the Adverse Health Effects Induced by Air Pollution: Current Evidence and Possible Mechanisms

Air pollution is a major social, economic, and health problem around the world. Children are particularly susceptible to the negative effects of air pollution due to their immaturity and excessive growth and development. The aims of this narrative review were to: (1) summarize evidence about the protective effects of breastfeeding on the adverse health effects of air pollution exposure, (2) define and describe the potential mechanisms underlying the protective effects of breastfeeding, and (3) examine the potential effects of air pollution on breastmilk composition and lactation. A literature search was conducted using electronic databases. Existing evidence suggests that breastfeeding has a protective effect on adverse outcomes of indoor and outdoor air pollution exposure in respiratory (infections, lung function, asthma symptoms) and immune (allergic, nervous and cardiovascular) systems, as well as under-five mortality in both developing and developed countries. However, some studies reported no protective effect of breastfeeding or even negative effects of breastfeeding for under-five mortality. Several possible mechanisms of the breastfeeding protective effect were proposed, including the beneficial influence of breastfeeding on immune, respiratory, and nervous systems, which are related to the immunomodulatory, anti-inflammatory, anti-oxidant, and neuroprotective properties of breastmilk. Breastmilk components responsible for its protective effect against air pollutants exposure may be long chain polyunsaturated fatty acids (LC PUFA), antioxidant vitamins, carotenoids, flavonoids, immunoglobins, and cytokines, some of which have concentrations that are diet-dependent. However, maternal exposure to air pollution is related to increased breastmilk concentrations of pollutants (e.g., Polycyclic aromatic hydrocarbons (PAHs) or heavy metals in particulate matter (PM)). Nonetheless, environmental studies have confirmed that breastmilk's protective effects outweigh its potential health risk to the infant. Mothers should be encouraged and supported to breastfeed their infants due to its unique health benefits, as well as its limited ecological footprint, which is associated with decreased waste production and the emission of pollutants.

Stem cells in human breast milk

Recent studies have demonstrated that breast milk contains a population of cells displaying many of the properties typical of stem cells. This review outlines progress made in this newly emerging field of stem cell biology and provides an analysis of the available data on purification, propagation and differentiation of certain types of progenitor cells from breast milk. The possible fates of breast milk cells, including microchimerism caused by their transmission to the distant organs of the infant, are also discussed. Unique properties of breast milk-derived stem cells, such as their unusually low tumorigenic potential and their negligible ability to form teratomas, are highlighted as obvious advantages for using these cells in regenerative therapy.

Environmental Enteric Dysfunction and Growth Failure/Stunting in Global Child Health

Approximately 25% of the world's children aged <5 years have stunted growth, which is associated with increased mortality, cognitive dysfunction, and loss of productivity. Reducing by 40% the number of stunted children is a global target for 2030. The pathogenesis of stunting is poorly understood. Prenatal and postnatal nutritional deficits and enteric and systemic infections clearly contribute, but recent findings implicate a central role for environmental enteric dysfunction (EED), a generalized disturbance of small intestinal structure and function found at a high prevalence in children living under unsanitary conditions. Mechanisms contributing to growth failure in EED include intestinal leakiness and heightened permeability, gut inflammation, dysbiosis and bacterial translocation, systemic inflammation, and nutrient malabsorption. Because EED has multiple causal pathways, approaches to manage it need to be multifaceted. Potential interventions to tackle EED include: (1) reduction of exposure to feces and contact with animals through programs such as improved water, sanitation, and hygiene; (2) breastfeeding and enhanced dietary diversity; (3) probiotics and prebiotics; (4) nutrient supplements, including zinc, polyunsaturated fatty acids, and amino acids; (5) antiinflammatory agents such as 5-aminosalicyclic acid; and (6) antibiotics in the context of acute malnutrition and infection. Better understanding of the underlying causes of EED and development of noninvasive, practical, simple, and affordable point-of-care diagnostic tools remain key gaps. "Omics" technologies (genomics, epigenomics, transcriptomics, proteomics, and metabolomics) and stable isotope techniques (eg, ¹³C breath tests) targeted at children and their intestinal microbiota will enhance our ability to successfully identify, manage, and prevent this disorder.

Association of 6 months of exclusive breastfeeding with higher fat-free mass in infants in a low-resource setting with high HIV prevalence in South Africa

Exclusive breastfeeding for 6 months is recommended by the World Health Organisation (WHO) for optimal health and growth of infants, but it is not a common practice in South Africa. A breastfeeding counselling programme was run to inform, encourage and support mothers to exclusively breastfeed their infants for 6 months, and mother-infant pairs were invited to participate in a research project to determine breast milk intake volumes using the dose-to-mother deuterium dilution stable isotope technique. This technique yields objective measurements of breast milk intake volumes and also enables determination of exclusivity of breastfeeding, which is most frequently determined by maternal recall and can be subject to bias. Exclusivity of breastfeeding at 6 weeks, 3 months and 6 months following birth of the infants was correlated with infant fat-free mass at 12 months, which was determined by the dose-to-infant deuterium dilution stable isotope technique. Results showed that infants who were exclusively breastfed for 6 months had a higher per cent fat-free mass at 12 months compared with infants who were not exclusively breastfed for 6 months (P < 0.05). This objective determination of both breastfeeding patterns and infant body composition gives weight to the WHO recommendation of exclusive breastfeeding for 6 months as it demonstrated adequate fat-free mass in infants at 12 months, even in an area with high HIV prevalence. © 2016 John Wiley & Sons Ltd.

HIV-Exposed Uninfected Infants in Zimbabwe: Insights into Health Outcomes in the Pre-Antiretroviral Therapy Era

The ZVITAMBO trial recruited 14,110 mother-infant pairs to a randomized controlled trial of vitamin A between 1997 and 2000, before the availability of antiretroviral therapy for HIV prophylaxis or treatment in Zimbabwe. The HIV status of mothers and infants was well characterized through 1-2 years of follow-up, leading to the largest cohort to date of HIV-exposed uninfected (HEU) infants (n = 3135), with a suitable comparison group of HIV-unexposed infants (n = 9510). Here, we draw on 10 years of published findings from the ZVITAMBO trial. HEU infants had increased morbidity compared to HIV-unexposed infants, with 50% more hospitalizations in the neonatal period and 30% more sick clinic visits during infancy, particularly for skin infections, lower respiratory tract infections, and oral thrush. HEU children had 3.9-fold and 2.0-fold higher mortality than HIV-unexposed children during the first and second years of life, respectively, most commonly due to acute respiratory infections, diarrhea/dysentery, malnutrition, sepsis, and meningitis. Infant morbidity and mortality were strongly related to maternal HIV disease severity, and increased morbidity remained until maternal CD4 counts were >800 cells/μL. HEU infants were more likely to be premature and small-for-gestational age than HIV-unexposed infants, and had more postnatal growth failure. Here, we propose a conceptual framework to explain the increased risk of infectious morbidity, mortality, and growth failure among HEU infants, hypothesizing that immune activation and inflammation are key drivers of both infection susceptibility and growth failure. Future studies should further dissect the causes of infection susceptibility and growth failure and determine the impact of ART and cotrimoxazole on outcomes of this vulnerable group of infants in the current era.