Non-nutritive bioactive components in maternal milk and offspring development: a scoping review

Maternal dietary fat during lactation shapes single nucleus transcriptomic profile of postnatal offspring hypothalamus in a sexually dimorphic manner in mice

Maternal overnutrition during lactation predisposes offspring to develop metabolic diseases and exacerbates the relevant syndromes in males more than females in later life. The hypothalamus is a heterogenous brain region that regulates energy balance. Here we combined metabolic trait quantification of mother and offspring mice under low and high fat diet (HFD) feeding during lactation, with single nucleus transcriptomic profiling of their offspring hypothalamus at peak lacation to understand the cellular and molecular alterations in response to maternal dietary pertubation. We found significant expansion in neuronal subpopulations including histaminergic (Hdc), arginine vasopressin/retinoic acid receptor-related orphan receptor β (Avp/Rorb) and agouti-related peptide/neuropeptide Y (AgRP/Npy) in male offspring when their mothers were fed HFD, and increased Npy-astrocyte interactions in offspring responding to maternal overnutrition. Our study provides a comprehensive offspring hypothalamus map at the peak lactation and reveals how the cellular subpopulations respond to maternal dietary fat in a sex-specific manner during development.

Infant feeding-a scoping review for Nordic Nutrition Recommendations 2023

The 2012 edition of the Nordic Nutrition Recommendations (NNR) included recommendations on breastfeeding, based on the most recent guidelines and recommendations from major national food and health authorities and organizations, systematic reviews, and some original research. For NNR 2023, the scope has been expanded and also includes formula feeding and the introduction of solid food. The main focus in this scoping review is on infants aged 0-12 months but also considers parts both before and beyond the first year, as the concept of 'the first 1000 days' emphasizes the importance of factors during pregnancy and the first 2 years of life for immediate and later health: physical as well as emotional and mental health. Breastmilk is the natural and sustainable way to feed an infant during the first months of life. Numerous studies have indicated immediate as well as long-term beneficial effects of breastfeeding on health for both the infant and the breastfeeding mother, and from a public health perspective, it is therefore important to protect, support, and promote breastfeeding. For full-term, normal weight infants, breastmilk is sufficient as the only form of nutrition for the first 6 months, except for vitamin D that needs to be given as supplement. The World Health Organization (WHO) and several other authoritative bodies therefore recommend exclusive breastfeeding during the first 6 months. Starting solids at about 6 months is necessary for both nutritional and developmental reasons. According to the European Food Safety Authority (EFSA) and the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN), solid foods are safe to give from 4 months although exclusive breastfeeding until 6 months is the desirable goal. Breastfeeding can continue together with complementary foods as long as it is mutually desired by the mother and child. If breastfeeding is not enough or for some reason discontinued before the infant is 4 months of age, the infant should be fed infant formula, and, when possible, breastfeeding should be continued alongside the formula feeding. If the infant is 4 months or older, starting with solids together with continued breastfeeding and/or formula feeding is an option. Infant formulas have been developed for infants who are not breastfed or do not get enough breastmilk. Home-made formula should not be given.

Chronic Stress Decreases Lactation Performance

The ability to provision offspring with milk is a significant adaptive feature of mammals that allows for considerable maternal regulation of offspring beyond gestation, as milk provides complete nutrition for developing neonates. For mothers, lactation is a period of marked increases in energetic and nutritive demands to support milk synthesis; because of this considerable increase in demand imposed on multiple physiological systems, lactation is particularly susceptible to the effects of chronic stress. Here, we present work that explores the impact of chronic stress during lactation on maternal lactation performance (i.e., milk quality and quantity) and the expression of key milk synthesis genes in mammary tissue using a Sprague-Dawley rat model. We induced chronic stress using a well-established, ethologically relevant novel male intruder paradigm for 10 consecutive days during the postpartum period. We hypothesized that the increased energetic burden of mounting a chronic stress response during lactation would decrease lactation performance. Specifically, we predicted that chronic exposure to this social stressor would decrease either milk quality (i.e., composition of proximate components and energy density) or quantity. We also predicted that changes in proximate composition (i.e., lipid, lactose, and protein concentrations) would be associated with changes in gene expression levels of milk synthesis genes. Our results supported our hypothesis that chronic stress impairs lactation performance. Relative to the controls, chronically stressed rats had lower milk yields. We also found that milk quality was decreased; milk from chronically stressed mothers had lower lipid concentration and lower energy density, though protein and lactose concentrations were not different between treatment groups. Although there was a change in proximate composition, chronic stress did not impact mammary gland expression of key milk synthesis genes. Together, this work demonstrates that exposure to a chronic stressor impacts lactation performance, which in turn has the potential to impact offspring development via maternal effects.