Mutation of SOCS2 induces structural and functional changes in mammary development.

Lactation is an essential process for mammals. In sheep, the R96C mutation in suppressor of cytokine signaling 2 (SOCS2) protein is associated with greater milk production and increased mastitis sensitivity. To shed light on the involvement of R96C mutation in mammary gland development and lactation, we developed a mouse model carrying this mutation (SOCS2KI/KI). Mammary glands from virgin adult SOCS2KI/KI mice presented a branching defect and less epithelial tissue, which were not compensated for in later stages of mammary development. Mammary epithelial cell (MEC) subpopulations were modified, with mutated mice having three times as many basal cells, accompanied by a decrease in luminal cells. The SOCS2KI/KI mammary gland remained functional; however, MECs contained more lipid droplets versus fat globules, and milk lipid composition was modified. Moreover, the gene expression dynamic from virgin to pregnancy state resulted in the identification of about 3000 differentially expressed genes specific to SOCS2KI/KI or control mice. Our results show that SOCS2 is important for mammary gland development and milk production. In the long term, this finding raises the possibility of ensuring adequate milk production without compromising animal health and welfare.

Inherent maternal type 2 immunity: Consequences for maternal and offspring health.

An inherent elevation in type 2 immunity is a feature of maternal and offspring immune systems. This has diverse implications for maternal and offspring biology including influencing success of pregnancy, offspring immune development and maternal and offspring ability to control infection and diseases such as allergies. In this review we provide a broad insight into how this immunological feature of pregnancy and early life impacts both maternal and offspring biology. We also suggest how understanding of this axis of immune influence is and may be utilised to improve maternal and offspring health.

Prolactin-mediated restraint of maternal aggression in lactation.

Aggressive behavior is rarely observed in virgin female mice but is specifically triggered in lactation where it facilitates protection of offspring. Recent studies demonstrated that the hypothalamic ventromedial nucleus (VMN) plays an important role in facilitating aggressive behavior in both sexes. Here, we demonstrate a role for the pituitary hormone, prolactin, acting through the prolactin receptor in the VMN to control the intensity of aggressive behavior exclusively during lactation. Prolactin receptor deletion from glutamatergic neurons or specifically from the VMN resulted in hyperaggressive lactating females, with a marked shift from intruder-directed investigative behavior to very high levels of aggressive behavior. Prolactin-sensitive neurons in the VMN project to a wide range of other hypothalamic and extrahypothalamic regions, including the medial preoptic area, paraventricular nucleus, and bed nucleus of the stria terminalis, all regions known to be part of a complex neuronal network controlling maternal behavior. Within this network, prolactin acts in the VMN to specifically restrain male-directed aggressive behavior in lactating females. This action in the VMN may complement the role of prolactin in other brain regions, by shifting the balance of maternal behaviors from defense-related activities to more pup-directed behaviors necessary for nurturing offspring.

Grb7 knockout mice develop normally but litters born to knockout females fail to thrive.

BACKGROUND: Growth factor receptor-bound 7 (Grb7) is an adaptor protein involved in signal transduction downstream of multiple receptor tyrosine kinases, including ERBB, FGFR, and PDGFR pathways. Experimental studies have implicated Grb7 in regulating cell proliferation, survival, migration, and invasion through its large repertoire of protein-protein interactions. RESULTS: Here, we describe the generation and characterization of a Grb7 knockout mouse. These mice are viable and fertile. A lacZ knock-in reporter was used to visualize Grb7 promoter activity patterns in adult tissues, indicating widespread Grb7 expression in glandular epithelium, the central nervous system, and other tissues. The sole defect observed in these animals was a failure of Grb7 knockout females to successfully raise pups to weaning age, a phenotype that was independent of both paternal and pup genotypes. CONCLUSIONS: These data suggest a regulatory role for Grb7 in mammary lactational physiology.

Using Organoids to Tap Mammary Gland Diversity for Novel Insight.

This article offers a comprehensive perspective on the transformative role of organoid technology on mammary gland biology research across a diverse array of mammalian species.The mammary gland's unique development and regenerative capabilities render this organ an ideal model for studying developmental evolution, stem cell behavior, and regenerative processes. The discussion extends to the use of cross-species mammary organoids to address key biological inquiries in evolution, tissue regeneration, cancer research, and lactation, highlighting the limitations of traditional mouse models and the benefits of incorporating a more diverse range of animal models.Advances in organoid biology have been critical in overcoming ethical and practical constraints of in-vivo studies, especially in human research. The generation of human and mouse mammary organoids that faithfully recapitulate in-vivo tissues marks a significant stride in this field. Parallel capabilities are now emerging for other mammals, as well.Utilizing mammary organoids from various species has the potential to make invaluable contributions to our understanding of mammary gland biology, with implications for regenerative medicine, cancer research, and lactation studies, thereby contributing to advancements in human health, agriculture, and nutrition science.

Chi-miR-3880 mediates the regulatory role of interferon gamma in goat mammary gland.

A healthy mammary gland is a necessity for milk production of dairy goats. The role of chi-miR-3880 in goat lactation is illustrated in our previous study. Among the differentially expressed genes regulated by chi-miR-3880, one seventh were interferon stimulated genes, including MX1, MX2, IFIT3, IFI44L, and DDX58. As the inflammatory cytokine interferon gamma (IFNγ) has been identified as a potential marker of caseous lymphadenitis in lactating sheep, the interaction between IFNγ and immune-related microRNAs was explored in this study. Chi-miR-3880 was found to be one of the microRNAs downregulated by IFNγ in goat mammary epithelial cells (GMECs). The study illustrated that IFNγ/chi-miR-3880/DDX58 axis modulates GMEC proliferation and lipid formation through PI3K/AKT/mTOR pathway, and regulates apoptosis through Caspase-3 and Bcl-2/Bax pathways. The role of the axis in mammary involution was reflected by the expression of p53 and NF-κB. In conclusion, IFNγ/chi-miR-3880/DDX58 axis plays an important part in lactation.

Identification and characterization of whole blood gene expression and splicing quantitative trait loci during early to mid-lactation of dairy cattle.

BACKGROUND: Characterization of regulatory variants (e.g., gene expression quantitative trait loci, eQTL; gene splicing QTL, sQTL) is crucial for biologically interpreting molecular mechanisms underlying loci associated with complex traits. However, regulatory variants in dairy cattle, particularly in specific biological contexts (e.g., distinct lactation stages), remain largely unknown. In this study, we explored regulatory variants in whole blood samples collected during early to mid-lactation (22-150 days after calving) of 101 Holstein cows and analyzed them to decipher the regulatory mechanisms underlying complex traits in dairy cattle. RESULTS: We identified 14,303 genes and 227,705 intron clusters expressed in the white blood cells of 101 cattle. The average heritability of gene expression and intron excision ratio explained by cis-SNPs is 0.28 ± 0.13 and 0.25 ± 0.13, respectively. We identified 23,485 SNP-gene expression pairs and 18,166 SNP-intron cluster pairs in dairy cattle during early to mid-lactation. Compared with the 2,380,457 cis-eQTLs reported to be present in blood in the Cattle Genotype-Tissue Expression atlas (CattleGTEx), only 6,114 cis-eQTLs (P < 0.05) were detected in the present study. By conducting colocalization analysis between cis-e/sQTL and the results of genome-wide association studies (GWAS) from four traits, we identified a cis-e/sQTL (rs109421300) of the DGAT1 gene that might be a key marker in early to mid-lactation for milk yield, fat yield, protein yield, and somatic cell score (PP4 > 0.6). Finally, transcriptome-wide association studies (TWAS) revealed certain genes (e.g., FAM83H and TBC1D17) whose expression in white blood cells was significantly (P < 0.05) associated with complex traits. CONCLUSIONS: This study investigated the genetic regulation of gene expression and alternative splicing in dairy cows during early to mid-lactation and provided new insights into the regulatory mechanisms underlying complex traits of economic importance.

Computational model captures cardiac growth in hypertensive pregnancies and in the postpartum period.

Heart growth in the pregnant patient helps maintain cardiovascular function while supporting the growing fetus. However, in some cases, the cardiovascular demand of pregnancy can trigger life-threatening conditions, including hypertensive disorders of pregnancy and peripartum cardiomyopathy. The mechanisms that control heart growth throughout pregnancy are unclear, and treating these diseases remains elusive. We previously developed a computational model that accounts for hormonal and hemodynamic interactions throughout pregnancy and demonstrated its ability to capture realistic cardiac growth in normal rat pregnancy. In this study, we evaluated whether this model could capture heart growth beyond normal pregnancy. After further validation of our normal pregnancy predictions, we tested our model predictions of three rat studies of hypertensive pregnancies. We next simulated the postpartum period and examined the impact of lactation on cardiac growth in rats. We demonstrate that our multiscale model can capture cardiac growth associated with new-onset hypertension during pregnancy and lactation status in the postpartum period. We conclude by elaborating on the potential clinical utility of our model in the future.NEW & NOTEWORTHY Our multiscale model predicts appropriate heart growth beyond normal pregnancy, including elevated heart weights in rats with induced hypertension during pregnancy and in lactating mice and decreased heart weight in nonlactating mice. Our model captures distinct mechanisms that result in similar organ-level growth, highlighting its potential to distinguish healthy from diseased pregnancy-induced growth.

Nicotinamide phosphoribosyl transferase in mammary gland epithelial cells is required for nicotinamide mononucleotide production in mouse milk.

Tissue-specific deficiency of nicotinamide phosphoribosyl transferase (NAMPT), the rate-limiting enzyme of the nicotinamide adenine dinucleotide (NAD+)-salvage pathway, causes a decrease of NAD+ in the tissue, resulting in functional abnormalities. The NAD+-salvage pathway is drastically activated in the mammary gland during lactation, but the significance of this has not been established. To investigate the impact of NAD+ perturbation in the mammary gland, we generated two new lines of mammary gland epithelial-cell-specific Nampt-knockout mice (MGKO). LC-MS/MS analyses confirmed that the levels of NAD+ and its precursor nicotinamide mononucleotide (NMN) were significantly increased in lactating mammary glands. We found that murine milk contained a remarkably high level of NMN. MGKO exhibited a significant decrease in tissue NAD+ and milk NMN levels in the mammary gland during lactation periods. Despite the decline in NAD+ levels, the mammary glands of MGKO appeared to develop normally. Transcriptome analysis revealed that the gene profiles of MGKO were indistinguishable from those of their wild-type counterparts, except for Nampt. Although the NMN levels in milk from MGKO were decreased, the metabolomic profile of milk was otherwise unaltered. The mammary gland also contains adipocytes, but adipocyte-specific deficiency of Nampt did not affect mammary gland NAD+ metabolism or mammary gland development. These results demonstrate that the NAD+ -salvage pathway is activated in mammary epithelial cells during lactation and suggest that this activation is required for production of milk NMN rather than mammary gland development. Our MGKO mice could be a suitable model for exploring the potential roles of NMN in milk.

The Association Between Breastfeeding and Growth Among Infants with Moderately Low Birth Weight: A Prospective Cohort Study.

OBJECTIVE: To assess the association between breastfeeding competency, as determined by Latch, Audible swallowing, Type of nipple, Comfort, and Hold (LATCH) and Preterm Infant Breastfeeding Behavior Scale (PIBBS) scores, and exclusive breastfeeding and growth among infants with low birth weight (LBW) in India, Malawi, and Tanzania. STUDY DESIGN: We conducted LATCH and PIBBS assessments among mother-infant dyads enrolled in the Low Birthweight Infant Feeding Exploration (LIFE) observational study of infants with moderately LBW (1500g-2499 g) in India, Malawi, and Tanzania. We analyzed feeding and growth patterns among this cohort. RESULTS: We observed 988 infants. We found no association between LATCH or PIBBS scores and rates of exclusive breastfeeding at 4 or 6 months. Higher week 1 LATCH and PIBBS scores were associated with increased likelihood of regaining birth weight by 2 weeks of age [LATCH: aRR 1.42 (95% CI 1.15, 1.76); PIBBS: aRR 1.15 (95% CI 1.07, 1.23); adjusted for maternal age, parity, education, residence, delivery mode, LBW type, number of offspring, and site]. Higher PIBBS scores at 1 week were associated with improved weight gain velocity (weight-for-age z-score change) at 1, 4, and 6 months [adjusted beta coefficient: 1 month 0.04 (95% CI 0.01, 0.06); 4 month 0.04 (95% CI 0.01, 0.06); and 6 month 0.04 (95% CI 0.00, 0.08)]. CONCLUSION: Although week 1 LATCH and PIBBS scores were not associated with rates of exclusive breastfeeding, higher scores were positively associated with growth metrics among infants with LBW, suggesting that these tools may be useful to identify dyads who would benefit from early lactation support.

Fluoxetine alters rat's milk properties causing impact on offspring's development.

Fluoxetine is an antidepressant used to treat several conditions including postpartum depression. This disease causes cognitive, emotional, behavioral and physical changes, negatively affecting the mother, child and family life. However, fluoxetine is excreted in breast milk, causing short and long-term effects on children who were exposed to the drug during lactation, so studies that seek to uncover the consequences of these effects are needed. Thus, the aim of this study was to evaluate the effects of fluoxetine on the nutritional characteristics of milk and on growth and neurobehavioral development of the offspring on a rat model. Lactating rats were divided into 4 groups: control group and three experimental groups, which were treated with different doses of fluoxetine (1, 10 and 20 mg/kg) during the lactation. Dams body weight and milk properties were measured, as well as offspring's growth and physical and neurobehavioral development. Results showed that the use of fluoxetine during lactation decreased dam's body weight and alters milk's properties, leading to a decrease in offspring's growth until adulthood. Therefore, the use of fluoxetine during lactation needs to be cautiously evaluated, with the benefits to the mothers and the associated risk to the offspring carefully balance.

Epigenetic programming for obesity and noncommunicable disease: From womb to tomb.

Several epidemiological, clinical and experimental studies in recent decades have shown the relationship between exposure to stressors during development and health outcomes later in life. The characterization of these susceptible phases, such as preconception, gestation, lactation and adolescence, and the understanding of factors that influence the risk of an adult individual for developing obesity, metabolic and cardiovascular diseases, is the focus of the DOHaD (Developmental Origins of Health and Disease) research line. In this sense, advancements in molecular biology techniques have contributed significantly to the understanding of the mechanisms underlying the observed phenotypes, their morphological and physiological alterations, having as a main driving factor the epigenetic modifications and their consequent modulation of gene expression. The present narrative review aimed to characterize the different susceptible phases of development and associated epigenetic modifications, and their implication in the development of non-communicable diseases. Additionally, we provide useful insights into interventions during development to counteract or prevent long-term programming for disease susceptibility.

Use of Theoretical Women and Model-Based Compartmental Analysis to Evaluate the Impact of Vitamin A Intake with or without a Daily Vitamin A Supplement on Vitamin A Total Body Stores and Balance During Lactation.

BACKGROUND: Inadequate vitamin A (VA) intake is common among lactating women in many communities worldwide, but high-dose VA supplementation for postpartum women is not recommended by the World Health Organization as an effective intervention. OBJECTIVES: To simulate the impact of VA intake via diet and daily VA supplements on VA total body stores (TBS) and balance in theoretical lactating women with low/moderate TBS. METHODS: We studied 6 theoretical subjects with assigned values for TBS from 219-624 µmol. Using Simulation, Analysis, and Modeling software and a previously published compartmental model for whole-body VA metabolism, we simulated TBS over 6 mo of established lactation for each subject under 4 conditions: 1) prelactation VA intake was increased to maintain VA balance (LSS); 2) prelactation VA intake was maintained (NLSS); 3) VA intake was the same as 2) but a daily VA supplement (2.8 µmol/d) was added (NLSS+S); and 4) VA intake was as 1) and the daily VA supplement was included (LSS+S). RESULTS: To compensate for the loss of VA via milk while VA balance was maintained (LSS) over 6 mo of lactation, VA intake had to increase by 0.8-1.87 µmol/d (n = 6) compared with NLSS. Over 6 mo of NLSS treatment, VA balance was negative (geometric mean, -0.77 µmol/d) compared with LSS, whereas balance was positive under NLSS+S and LSS+S conditions (0.75 and 1.5 µmol/d, respectively). For LSS, the proportion of total VA disposal was 37% via breastmilk, 32% from VA stores, and 32% from nonstorage tissues. CONCLUSIONS: Adding a daily VA supplement (2.8 µmol/d) to the diet of lactating women with suboptimal VA intake may effectively counterbalance the negative VA balance resulting from the output of VA via breastmilk and thus benefit both mother and infant by maintaining or increasing VA stores and breastmilk VA concentration.

Effects of Breastfeeding Promotion Intervention and Dietary Treatment in Postpartum Women with Overweight and Obesity: Results from a Randomized Controlled Trial on Weight and Cardiometabolic Risk Factors.

BACKGROUND: Childbearing increases the risk of weight gain and cardiometabolic disease. The reset hypothesis suggests that lactation has protective cardiometabolic effects on the mother. The hypothesis is based on observational studies, and the possible interacting role of weight loss needs to be elucidated. OBJECTIVES: This study aimed to examine the individual and interaction effects of a breastfeeding promotion intervention (BPI) and dietary intervention for weight loss postpartum (Diet) on body weight and cardiometabolic risk factors at 6 mo postpartum. METHODS: Pregnant women (n = 156) with a prepregnancy BMI of 25 to 35 kg/m2 were randomized to 4 groups in a 2 × 2 factorial design: BPI, Diet, both treatments, or no treatment. BPI consisted of individual counseling by a lactation consultant during pregnancy, at childbirth, and monthly thereafter or more frequently based on individual needs. Diet was initiated at 11 wk postpartum. Body weight, body composition, waist and hip circumferences, markers of lipid and glucose metabolism, and blood pressure were measured at 2 wk and 6 mo postpartum. We analyzed main and interaction effects using 2-way analysis of covariance adjusted for baseline values. RESULTS: Among the participants attending both visits (n = 108), 99% practiced any breastfeeding at baseline and 97% at follow-up. The BPI did not affect rates of exclusive or partial breastfeeding, age at introduction of complementary foods, or have main effects on body weight or cardiometabolic risk factors. There was a main effect of Diet reducing body weight, fat mass, fat-free mass, percentage fat mass, waist and hip circumferences, fasting glucose, and insulin (all P ≤ 0.03), with no interactions between the treatments. CONCLUSIONS: There were no effects of BPI on body weight or cardiometabolic risk factors at 6 mo postpartum. Diet caused weight loss and had favorable effects on risk factors for cardiovascular disease and type 2 diabetes. This study was registered at clinicaltrials.gov as NCT03580057.

Zinc Supplementation Initiated Prior to or During Pregnancy Modestly Impacted Maternal Status and High Prevalence of Hypozincemia in Pregnancy and Lactation: The Women First Preconception Maternal Nutrition Trial.

BACKGROUND: Data regarding effects of small-quantity-lipid-based nutrient supplements (SQ-LNS) on maternal serum zinc concentrations (SZC) in pregnancy and lactation are limited. OBJECTIVES: The objectives of this study were to evaluate the effect of preconception compared with prenatal zinc supplementation (compared with control) on maternal SZC and hypozincemia during pregnancy and early lactation in women in low-resource settings, and assess associations with birth anthropometry. METHODS: From ∼100 women/arm at each of 3 sites (Guatemala, India, and Pakistan) of the Women First Preconception Maternal Nutrition trial, we compared SZC at 12- and 34-wk gestation (n = 651 and 838, respectively) and 3-mo postpartum (n = 742) in women randomly assigned to daily SQ-LNS containing 15 mg zinc from ≥3 mo before conception (preconception, arm 1), from ∼12 wk gestation through delivery (early pregnancy, arm 2) or not at all (control, arm 3). Birth anthropometry was examined for newborns with ultrasound-determined gestational age. Statistical analyses were performed separately for each time point. RESULTS: At 12-wk gestation and 3-mo postpartum, no statistical differences in mean SZC were observed among arms. At 34-wk, mean SZC for arms 1 and 2 were significantly higher than for arm 3 (50.3, 50.8, 47.8 µg/dL, respectively; P = 0.005). Results were not impacted by correction for inflammation or albumin concentrations. Prevalence of hypozincemia at 12-wk (<56 µg/dL) was 23% in Guatemala, 26% in India, and 65% in Pakistan; at 34 wk (<50 µg/dL), 36% in Guatemala, 48% in India, and 74% in Pakistan; and at 3-mo postpartum (<66 µg/dL) 79% in Guatemala, 91% in India, and 92% in Pakistan. Maternal hypozincemia at 34-wk was associated with lower birth length-for-age Z-scores (all sites P = 0.013, Pakistan P = 0.008) and weight-for-age Z-scores (all sites P = 0.017, Pakistan P = 0.022). CONCLUSIONS: Despite daily zinc supplementation for ≥7 mo, high rates of maternal hypozincemia were observed. The association of hypozincemia with impaired fetal growth suggests widespread zinc deficiency in these settings. This trial is registered at clinicaltrials.gov as #NCT01883193.

Effects of intrauterine position during gestation on specific endocrine and behavioral parameters that impact reproduction in domestic rabbits.

Prior studies from others, performed in a different breed, reported that doe rabbits developing between two male siblings (2 M) during gestation display characteristics indicative of masculinization: larger anogenital distance (AGD), larger submandibular glands, and higher chinning frequency than females with zero (0 M) or one (1 M) contiguous brothers. Similar effects are provoked by injecting androgens to the pregnant doe suggesting that prenatal androgen exposure masculinizes female embryos. To further understand the scope of such masculinization we compared 0 M, 1 M, and 2 M females regarding behavioral, neuroendocrine, and somatic parameters, related or not to reproduction. IUP did not impact: body weight, sexual receptivity, mating-induced LH secretion, maternal nest-building, litter size, or milk output. At puberty: a) chinning frequency was: 0 M and males>1 M and 2 M; b) ambulation in open field was lowest in 1 M females and males. IUP effects on AGD were significant only on postnatal day 1: 0 M, 1 M, and males>2 M, in contrast to earlier study. Willingness to nurse at delivery was less frequent in 2 M than in 1 M and 0 M does and correlated with nursing occurrence across lactation. Does that did not nurse at parturition delivered fewer kits/min than those that nursed then, regardless of IUP. The duration of nursing bouts across lactation was significantly longer in the1 M and 2 M does that showed this behavior on postpartum days 1-20. Our findings indicate that IUP is associated with alterations in specific aspects of postpartum maternal behavior.

Attention-deficit/hyperactivity disorder in pregnancy and the postpartum period.

Attention-deficit/hyperactivity disorder is a childhood-onset neurodevelopmental disorder that frequently persists into adulthood with 3% of adult women having a diagnosis of attention-deficit/hyperactivity disorder. Many women are diagnosed and treated during their reproductive years, which leads to management implications during pregnancy and the postpartum period. We know from clinical practice that attention-deficit/hyperactivity disorder symptoms frequently become challenging to manage during the perinatal period and require additional support and attention. There is often uncertainty among healthcare providers about the management of attention-deficit/hyperactivity disorder in the perinatal period, particularly the safety of pharmacotherapy for the developing fetus. This guideline is focused on best practices in managing attention-deficit/hyperactivity disorder in the perinatal period. We recommend (1) mitigating the risks associated with attention-deficit/hyperactivity disorder that worsen during the perinatal period via individualized treatment planning; (2) providing psychoeducation, self-management strategies or coaching, and psychotherapies; and, for those with moderate or severe attention-deficit/hyperactivity disorder, (3) considering pharmacotherapy for attention-deficit/hyperactivity disorder, which largely has reassuring safety data. Specifically, providers should work collaboratively with patients and their support networks to balance the risks of perinatal attention-deficit/hyperactivity disorder medication with the risks of inadequately treated attention-deficit/hyperactivity disorder during pregnancy. The risks and impacts of attention-deficit/hyperactivity disorder in pregnancy can be successfully managed through preconception counselling and appropriate perinatal planning, management, and support.

Establishment of a measurement system to evaluate breast milk transfer of biological agents using dry filter paper: A multi-institutional study.

AIMS: Information on breastfeeding and safety of biologics in infants is lacking due to difficulties in case collection. We evaluated methods for determining the concentration of biologics in breast milk using a dry filter method that can simplify the collection, storage and transport of breast milk. METHODS: To generate dried filter paper (DFP) samples, approximately 30 µL of breast milk was placed onto a Whatman 903 card and punched out. After extraction, the supernatant was measured using an enzyme-linked immunosorbent assay. Three concentrations of each drug were prepared in liquid breast milk (LBM) and DFP samples to determine their stability up to 28 days after storage at 2-8°C or -20°C for LBM and 25 ± 5°C for DFP. LBM and DFP samples were also provided by nursing mothers using biologics during lactation, and drug concentrations in both samples were compared. The agreement between the two measurement methods was confirmed by Bland-Altman analysis. RESULTS: Breast milk was provided by 12 mothers who used biologics (tocilizumab, abatacept, etanercept, golimumab, sarilumab and belimumab). The coefficients of variation for within-run and between-run precision for the six drugs were within 15% for both LBM and DFP, and accuracy was within 90%-110% of the quality controls. After 28 days, concentrations remained at more than 90%. The difference between the values obtained by each method was within the acceptable range of error (-12.1 to +16.6 ng/mL). CONCLUSIONS: A method for determining the concentration of biologics using DFP is expected to help improve pharmacotherapy for lactating women.

Effect of chronic maternal L-Glu intake during gestation and/or lactation on oxidative stress markers, AMPA Glu1 receptor and adenosine A1 signalling pathway from foetal and neonatal cerebellum.

L-Glutamate (L-Glu) is an amino acid present in the diet that plays a fundamental role in the central nervous system, as the main excitatory neurotransmitter participating in learning and memory processes. In addition, the nucleoside adenosine has a crucial role in L-Glu metabolism, by regulating the liberation of this neurotransmitter through four different receptors: A1, A2A, A2B and A3, which activate (A2A and A2B) or inhibit (A1 and A3) adenylate cyclase pathway. L-Glu at high concentrations can act as a neurotoxin and induce oxidative stress. The study of the oxidative stress correlated with an excess of L-Glu consumption during maternity is key to understand its effects on foetuses and neonates. Previous studies have shown that there is a change in the receptor levels in the brain of pregnant rats and their foetuses when mothers are administered L-Glu during gestation; however, its effect on the cerebellum is unknown. Cerebellum is known to be responsible for motor, cognitive and emotional functions, so its possible involvement after L-Glu consumption is an important issue to study. Therefore, the aim of the present work was to study the effect of L-Glu exposure during gestation and lactation on oxidative stress biomarkers and neurotransmitter receptors from the cerebellum of foetuses and neonates. After maternal L-Glu intake during gestation, oxidative stress was increased, as the ionotropic L-Glu receptors, and GluR1 AMPA subunit levels were altered in foetuses. A1 adenosine receptor suffered changes after L-Glu treatment during gestation, lactation or both, in lactating neonate cerebellum, while adenylate cyclase activity remain unaltered. Further studies will be necessary to elucidate the importance of L-Glu intake and its possible excitotoxicity in the cerebellum of Wistar rats during the pregnancy period and their involvement in long-term neurodegeneration.

The use of breast milk iodine concentration in the first week of lactation as a biomarker of iodine status in breast-feeding women.

Breast milk iodine concentration (BMIC) is a promising indicator of iodine status in lactating women. However, there are limited data on its usefulness to reflect maternal iodine deficiency. Therefore, the aim of our study was to assess iodine concentration in breast milk and urine samples in exclusively breast-feeding women. Eligible pregnant women undergoing routine antenatal care in a large hospital in Shaanxi Province, China, were followed up from the third trimester of pregnancy until the first week of lactation. Urine samples (20 ml) were collected during pregnancy and lactation. Iodine concentration in samples was measured based on Sandell-Kolthoff reaction. Breast milk samples (5 ml) were provided during lactation. A receiver operating curve (ROC) was constructed to determine the diagnostic performance of BMIC. An iodine-specific FFQ was completed twice during pregnancy and lactation. A total of 200 women completed the study. The overall median BMIC was 89 µg/l, indicating iodine sufficiency (i.e. BMIC reference range between 60 and 465 µg/l). Women reported similar median urinary iodine concentration (UIC) during pregnancy and lactation (112 and 113 µg/l, respectively), but their iodine status differed - mild-to-moderate iodine deficiency during pregnancy and iodine sufficiency during lactation. The ROC for BMIC using UIC as a reference standard was 0·755 (95 % CI: 0·644, 0·866). In conclusion, this study demonstrated that women were iodine sufficient in the first week of lactation as assessed by UIC, which was consistent with BMIC. These findings suggested that BMIC is a useful biomarker to assess iodine status in lactating women.