Mature Milk Research Articles

A handheld milk conductivity sensing device (Mylee) for measuring secretory activation progress in lactating women: a device validation study

BackgroundHuman milk electrolytes are known biomarkers of stages of lactation in the first weeks after birth. However, methods for measuring milk electrolytes are available only in laboratory or expert settings. A small handheld milk sensing device (Mylee) capable of determining on-site individual secretory activation progress from sensing the conductivity of a tiny milk specimen was developed. Here we evaluate the validity of a novel milk-sensing device (Mylee) for measuring the progress of milk maturation and secretory activation status.MethodsRetrospective data analysis of laboratory records generated using the Mylee device. Device conductivity measurements were assessed for accuracy, reliability and stability in rigorous laboratory tests with standard materials. A set of human milk specimens (n = 167) was used to analyze the agreement between the milk maturation score and laboratory measurements of the secretory activation biomarker milk sodium [Na+].ResultsThe Mylee device was demonstrated to have excellent reproducibility (CV95%<5%) and accuracy (error < 5%) for conductivity measurements of a small specimen (350 µl), with good device stability and almost perfect inter-device unit reliability (ICC > 0.90). With regression analysis, we revealed excellent agreement between Mylee milk maturation (MM%) output or its raw conductivity signal and laboratory measurements of conductivity and sodium [Na+] in a dataset of milk specimens (n = 167; R2 > 0.9). The Mylee MM% score showed good predictive ability for secretary activation status, as determined by sodium threshold (18 mmol/L) in human milk specimens.ConclusionsIn this study, we demonstrated the reliability and validity of the Mylee device and its ability to detect on-site milk secretory activation in a manner comparable to that of electrolyte-based methods. The novel MyLee device offers the potential to generate real-time information about the lactation stage, measured by mothers at the commodity of their home.

Microbial Adaptation in Human Milk: Unraveling the Effects of Gestational Age and Lactation Stage Among Indian Mothers

Introduction Human milk once considered sterile is a habitat for a diverse microbiome. Breast milk is vital in the formation of the newborn microbiome and affects various health outcomes. Its microbiota is influenced by mode of delivery, geographic location, mastitis, diet, obesity, and gestational age and lactation stage. Knowledge of region-wise data regarding human milk microbiome is the need of an hour. Purpose The aim of this study was to isolate and characterize breast milk microbiome and to know the effect of gestational age and lactation stage on it. Methods A prospective longitudinal study included 30 mothers, of whom 10 were of gestational age &lt; 32 weeks, 10 between 32 and 36 6/7 weeks, and the remaining 10 above 37 weeks of gestation at the time of delivery. Milk samples were collected and analyzed for microbiome at three different time points, that is, colostrum, transition milk (7-9 days), and mature milk (after 14 days). Results 381bacterial colonies were isolated and 242 colonies were identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) and cross-verified with 16s RNA sequencing, which included 38 different bacterial species. The majority of colonies (229/242) identified belonged to 4 phyla- firmicutes 119 (51.97%), proteobacteria 48 (20.96%), Bacillota 41 (17.9%), and actinobacteria 21 (9.17%). Bacterial diversity increased with gestational age and lactation stage and the proportion of actinobacteria and Bacillota increased significantly with lactation stage ( P value −.039), showing that preterm mother’s milk has a lesser quantity of beneficial bacteria. Conclusion This study provided the insight into effect of gestational age and lactation stage on breast milk microbiome. The diversity of milk microbiome increases with lactation and gestational age; however, the preterm mother’s milk lacks sufficient beneficial bacteria.

Unusual free trisaccharides in caprine colostrum discovered by logically derived sequence tandem mass spectrometry

Free oligosaccharides in human milk have many biological functions for infant health. The reducing end of most human milk oligosaccharides is lactose, and caprine milk was reported to contain oligosaccharides structurally similar to those present in human milk. The structures of oligosaccharides were traditionally determined using nuclear magnetic resonance spectroscopy or enzyme digestion followed by various detection methods, e.g., liquid. Mass spectrometry has much higher sensitivity than nuclear magnetic resonance spectroscopy and enzyme digestion. However, conventional mass spectrometry methods only determine part of the structures of oligosaccharides, i.e., compositions and linkage positions. In this study, we used the latest developed mass spectrometry method, namely logically derived sequence tandem mass spectrometry, to determine the complete structures (i.e., composition, linkage positions, anomericities, and stereoisomers) of free neutral trisaccharides in caprine colostrum and mature milk. The high sensitivity of mass spectrometry enables us to discover oligosaccharides of low abundance. Isomers of (Hex)2HexNAc, (Hex)3, and (Hex)2Fuc which have not been reported before were identified. Many of them do not have lactose at the reducing end. Instead, the reducing end is either Glcβ-(1–4)-Glc or Glcβ-(1–4)-GlcNAc. These unusual oligosaccharides are higher in concentration and more structurally diverse in caprine colostrum than that in caprine mature milk and human milk. The structural diversity indicates more complicated biosynthetic pathways of caprine milk compared to that of human milk.

Evaluating Metabolic Profiling of Human Milk Using Biocrates MxP® QUANT 500 Assay.

Background/Objectives: Metabolic profiling of human milk (HM) is indispensable for elucidating mother-milk-infant relationships. Methods: We evaluated the Biocrates MxP® Quant 500 assay for HM-targeted metabolomics (106 small molecules, 524 lipids) and analyzed in a feasibility test HM from apparently healthy Brazilian mothers (A: 2-8, B: 28-50, C: 88-119 days postpartum, ntotal = 25). Results: Of the 630 possible signatures detectable with this assay, 506 were above the limits of detection in an HM-pool (10 µL) used for assay evaluation, 12 of them above the upper limit of quantitation. Analyzing five different HM-pool volumes (2-20 µL) revealed acceptable linearity for 458 metabolites. Intraday accuracy of 80-120% was attained by 469 metabolites after spiking and for 342 after a 1:2 dilution. Analyzing HM from Brazilian mothers revealed significantly lower concentrations in colostrum vs. mature milk for many flow-injection analyses (FIA) and only a few LC-MS metabolites, including triglycerides, sphingomyelins, and phosphatidylcholines. Higher concentrations at the later lactation stages were found predominantly for amino acids and related compounds. Conclusions: The MxP Quant® 500 assay is a useful tool for HM metabolic profiling, minimizing analytical bias between matrices, and enhancing our ability to study milk as a biological system.

Characterization of the functional component in human milk and identification of the molecular mechanisms undergoing prematurity.

Human milk (HM) is the earliest form of extrauterine communication between mother and infant, that could promote early programming. The aim of this study is to look for specific biological processes, particularly those undergoing prematurity, modulated by proteins and miRNAs of HM that could be implicated in growth and development. This is a prospective, observational, single center study in which we collected 48 human milk (HM) samples at two distinct stages of lactation: colostrum (first 72-96h) and mature milk (at week 4 post-delivery) from mothers of very preterm newborns (<32 weeks) and term (≥37 and<42 weeks). Qualitative and quantitative proteomic and transcriptomic analysis was done in our samples. We performed isolation and characterization of HM extracellular vesicles (EVs) to carry out proteomic and transcriptomic analysis in colostrum (CM) and mature milk (MM). Proteomic analysis revealed a functional role of CM in immunological protection and MM in metabolic processes. TENA, TSP1 and OLF4, proteins with roles in immune response and inflammatory modulation, were upregulated in CM vs MM, particularly in preterm. HM modulation differed depending on gestational age (GA). The miRNAs identified in HM are implicated in structural functions, including growth and neurological development. miRNA-451a was differentially expressed between groups, and downregulated in preterm CM. Because the particularities of each GA are reflected in the EVs content of HM, providing newborns with HM from their own mother is the optimal way for satisfying their specific needs. Although the role of the proteomic profile of CM and MM of different GA in relation to neurodevelopment has been previously described, this is the first study to show a complete functional characterization of HM (proteome, miRNA at the same time), unmasking the molecular mechanisms related to EVs signaling and their functional role in preterm.

Carotenoid profile in maternal and cord plasma and its trends in breast milk during lactation: a comparative study among three cities in northern China.

Increasing evidence suggests that carotenoids play an important role in visual and cognitive development during early life. This study aimed to depict the carotenoid profile in maternal/cord plasma and breast milk in three northern cities of China while investigating the association between dietary carotenoid intake and breast milk carotenoid levels. We enrolled 990 lactating mothers from three urban northern Chinese cities to collect breast milk (including colostrum, transitional milk, early mature milk, middle mature milk, and late mature milk). Among them, 90 participants also provided maternal/cord blood. The dietary carotenoid intake was recorded in the corresponding stages according to the Food Frequency Questionnaire and 24-hour dietary recall. The levels of carotenoids (lutein, zeaxanthin, β-cryptoxanthin, β-carotene, and lycopene) in maternal/cord plasma and breast milk were analyzed using high-performance liquid chromatography. We found a significant correlation between carotenoid concentrations in maternal and cord plasma. Moreover, carotenoid concentrations in maternal plasma were significantly higher than those in cord plasma. The total carotenoid levels in breast milk decreased from colostrum to late mature milk. β-Carotene predominated in colostrum, whereas lutein dominated in transitional and mature milk. We also found that breast milk carotenoid levels correlated with dietary carotenoid intake to a certain extent, particularly during the early stages of lactation. Therefore, we encourage women to appropriately increase their dietary intake of carotenoid-rich vegetables and fruits during pregnancy and lactation, particularly during work hours after lactation leave. Moreover, the variance of the carotenoid profile in maternal/cord plasma and breast milk across the three cities implied the necessity of further depicting the carotenoid status and influencing factors across different areas in China.

Proteomics and phosphoproteomics differences between human and cow milk fat globule membrane: An innovative guide for infant formula.

This study employed proteomics and phosphoproteomics to compare protein expression and phosphorylation modifications in the milk fat globule membrane (MFGM) of human and bovine mature milk. A total of 410 proteins and 73 phosphorylation sites on 49 proteins were identified in the MFGM of bovine and human mature milk, respectively. Differential analysis revealed 40 differentially expressed proteins and 8 differentially phosphorylated sites, followed by bioinformatics analysis. Seven overlapping proteins were identified, with GLYCAM1 and Alpha-S2-casein showing significant differences in both protein expression and phosphorylation modifications, particularly in relation to immune functions. The results suggest that bovine MFGM may provide unique advantages in supporting infant immune systems and promoting gut health, offering valuable insights for future innovation in infant formula development.

Analysis of nutritional profiles in colostrum and mature milk of giant panda (Ailuropoda melanoleuca) based on proteomics

Breast milk plays a crucial role in giant panda growth (Ailuropoda melanoleuca). This study aimed to analyse nutritional profiles in colostrum and mature milk. Based on DIA proteomics, the colostrum was rich in immunoreactive proteins, anti‐inflammatory and antimicrobial proteins. The mature milk contained proteins involved in ribosome, fatty acid degradation and amino acid metabolism. Besides, there were more amino acids and saturated fatty acids in mature milk than colostrum. This research enclosed the nutritional difference in colostrum and mature milk of giant panda innovatively, and provided scientific evidence for exploiting substitutes that simulate natural breast milk for different lactation stages.

Dynamics of Selected Milk Quality Parameters and Expression Patterns of miR-26a, miR-27a, and miR-148a During Transition From Colostrum to Mature Milk in Awassi Sheep.

This study investigated expressions of microRNA (miR)-26a, miR-27a, and miR-148a in plasma, colostrum and milk collected on different days (0th, 4th, 7th, 14th, and 28th days) during transition from colostrum to milk in Awassi sheep. Relationships between miRNAs and quality parameters were also explored. During transition, Somatic Cell Count, Fat-free dry matter, protein, lactose decreased, pH, freezing point (FP), electrical conductivity (EC) increased. Malondialdehydes (MDA) were tended to decrease in plasma and milk. Compared to 0th day, miR-26a was upregulated approximately 27-folds and 17-folds in 14th and 28th days, in milk. On 14th day, miR-27a showed almost 18-folds upregulation, while miR-148a was downregulated more than fivefolds on 7th and 14th days. In plasma, miR-26a was upregulated almost 40-folds and sevenfolds on 7th and 14th days. Additionally, miR-27a was upregulated by approximately fivefolds on 4th day, around 20-folds on 7th day, and about fourfolds on 14th day. miR-148a was upregulated approximately 11-folds on 7th day. While miR-26a positively correlated with miR-27a, pH, fat, and EC, it was negatively correlated with MDA in plasma. miR-27a was positively correlated with miR-148a and pH. Plasma miR-148a and milk miR-148a were negatively correlated. miR-26a and miR-27a were positively correlated in milk. Milk miR-26a was positively correlated with pH, FP, and EC, while it was negatively correlated with fat, milk and plasma MDA. Milk miR-27a was negatively correlated with fat and MDA, but positively with EC. The results obtained for the first-time during transition indicate potentials of miR-26a and miR-27a to act as biomarkers for sheep milk quality.

Bioactive Peptides in Greek Goat Colostrum: Relevance to Human Metabolism.

Colostrum is essential for the survival and development of newborn mammals. This primary source of nourishment during the first days of infant life is rich in functional components conductive to the enhancement of neonate immunity and growth. Compared with mature milk, a higher protein and peptide content is observed in colostrum, whilst it is low in fat and carbohydrates. The functional properties of colostrum are closely linked to the release of bioactive peptides during the gastrointestinal digestion of colostrum proteins. Our study aimed to comprehensively analyze the whey proteome of colostrum from indigenous Greek goats and to examine the influence of bioactive peptides released during digestion on human metabolism. Colostrum and mature milk samples from healthy ewes were subjected to nanoLC-MS/MS analysis, revealing differentially expressed proteins. These proteins were functionally characterized and subjected to in silico digestion. Using machine learning models, we classified the peptide functional groups, while molecular docking assessed the binding affinity of the proposed angiotensin-converting enzyme (ACE)- and dipeptidyl peptidase IV (DPPIV)-inhibitory peptides to their target molecules. A total of 898 proteins were identified in colostrum, 40 of which were overexpressed compared with mature milk. The enzymatic cleavage of upregulated proteins by key gastrointestinal tract proteases and the downstream analysis of peptide sequences identified 117 peptides predicted (with >80% confidence) to impact metabolism, primarily through modulation of the renin-angiotensin system, insulin secretion, and redox pathways. This work advances our understanding of dietary bioactive peptides and their relevance to human metabolism, highlighting the potential health benefits of colostrum consumption.

Changes in photoperiod during the dry period impact colostrum production in Holstein and Jersey cows.

Multiparous Holstein cows exposed to short-day photoperiod (SDPP) of 8 h of light per day during their dry period produced up to 3.2 kg more milk per day compared with cows exposed to long-day photoperiod (LDPP) of 16 h of light per day; it is unknown if a similar response would be observed for Jersey cow milk production. The objective of this study was to determine the effect of photoperiod during the dry period on subsequent colostrum and milk production in Holstein and Jersey cattle. Holstein and Jersey cows (n = 33) were dried off 60 d before their due date and randomly assigned to SDPP (Holstein, n = 9; Jersey, n = 8) or LDPP (Holstein, n = 8; Jersey, n = 8) until calving. Cows were weighed at the time of enrollment (d 0) and were housed in an enclosed barn at 20°C and exposed to 250 to 450 lx during periods of light and <10 lx during periods of darkness. At calving, colostrum volume was weighed and tested for relative protein concentration with a Brix refractometer and a sample was collected for component analysis (fat, protein, lactose, SNF) via infrared spectroscopy, as well as IgA, IgG, IgG1, IgM, lactoferrin, and SCS analysis. After calving, cows were returned to the freestall barn and exposed to ambient photoperiod and temperature. Milk production data were collected for 15 wk postcalving. Data were analyzed using PROC MIXED in SAS (SAS 9.4; SAS Institute Inc., Cary, NC) with treatment, breed, and d 0 weight as fixed effects. PROC MIXED with repeated measures was used to evaluate the relationship of day length and breed with mature milk volume, fat, and protein production. Random effects included replicate, lactation number, genetic inbreeding percentage, previous lactation mature equivalent 305-d protein production, and calf sex. For colostrum, Brix score, colostral protein, fat, IgA, and IgM were increased in Jersey cows compared with Holstein cows. Total colostrum weight, SNF, lactose, lactoferrin, IgG, IgG1, and SCS did not differ by breed or treatment. Postcalving, ECM production was increased in Holstein cows compared with Jersey cows but unaffected by photoperiod treatment. Conversely, milk protein percentage was increased for Jersey cows relative to Holstein cows but was unaffected by photoperiod treatment. Milk fat increased in LDPP Holstein cows compared with SDPP Jersey cows during the first week of lactation, which is likely due to the transition from colostrum to mature milk production. Overall, photoperiod did not affect colostrum production, but differences by breed were detected. Photoperiod during the dry period did not affect mature milk production or protein, but milk fat percentage was affected by photoperiod × breed. Therefore, altered lighting during the dry period does not unfavorably affect colostrum or milk production in Jersey or Holstein cows.

Maternal fish oil supplementation enhances nutrient transport in the placenta and milk biosynthesis in the mammary gland via the GPR120 signaling pathway.

Maternal fish oil (FO) supplementation during pregnancy has been shown to improve pregnancy outcomes. FO is recognized as dietary source for n-3 polyunsaturated fatty acids (n-3 PUFAs). While early research has focused on the benefits of n-3 PUFAs for fetal neurodevelopment, retinal maturation and neonatal behavior, their roles in the placenta during late pregnancy and in the mammary gland during lactation still remain unknow. Here, we aim to clarify the mechanisms by which maternal supplementation with FO during pregnancy and lactation affects placental and mammary gland function. We evaluated the effects of FO on maternal placental nutrient transport, mammary gland milk synthesis and offspring growth. We then explored the molecular mechanisms by which docosahexaenoic acid (DHA) affects the biological function of placental trophoblast cells and mammary epithelial cells through in vitro experiments. Finally, a lipopolysaccharide-challenged experiment was performed to access the potential of maternal FO supplementation in alleviating offspring intestinal inflammation. Maternal supplementation with FO during late pregnancy increased offspring birth weight, associated with enhanced maternal placental vascularization and nutrient transporter abundance. Additionally, maternal FO supplementation during lactation improved milk biosynthesis, increasing the fat, protein, and non-fat solids content in both colostrum and mature milk, thereby promoting offspring growth. The stimulatory effects of DHA on nutrient transportation in placental trophoblast cells and nutrient secretion in mammary gland epithelial cells were mediated by GPR120 signaling pathways. Furthermore, maternal FO supplementation strengthened the placental barrier, reduced placental inflammation, oxidative stress and alleviated lipopolysaccharide-induced intestinal inflammation in offspring. Maternal FO supplementation during late pregnancy and lactation enhances offspring growth by increasing placental nutrient transport and milk biosynthesis, mediated by GPR120. Additionally, maternal FO supplementation reduces the susceptibility of offspring to intestinal inflammation.

Tracing Zinc's Role in Preterm Infants' Health: A Narrative Review.

Zinc (Zn) is a trace element involved in numerous physiological processes, including enzyme function, gene transcription, and cell signaling. Its importance is especially pronounced in preterm infants, who are at high risk of Zn deficiency due to disrupted transplacental transfer, high nutrient demands, and medical complications. The inherent risk of Zn deficiency in this population is further increased by poor Zn dietary intake. Human milk from preterm mothers contains low concentrations of Zn, although it is highly bioavailable. Additionally, the Zn content steadily declines from colostrum (first few days postpartum) to mature milk (>10-14 d postpartum). Formula milk contains higher Zn concentrations to compensate for nutrient losses during production and storage, and lower bioavailability compared with human milk, which is further decreased in case of high phytate content, such as in soy milk-based formulas. Zn supplements may prove useful in meeting the preterm infant's needs, although caution is warranted regarding potential interactions with other nutrients within multinutrient supplements. Early detection of Zn deficiency is challenging due to the lack of reliable Zn status biomarkers, necessitating a high index of suspicion. Clinical signs of Zn deficiency can range from mild, nonspecific symptoms to severe, multisystem involvement. Chronic deficiency may lead to failure to thrive. Zn supplementation can support growth and mitigate comorbidities in preterm infants, although variability across studies complicates efforts to establish optimal dosing, and define safety and long-term effects. Although rare, Zn toxicity in preterm infants should not be overlooked, especially in infants on long-term parenteral nutrition. This narrative review aimed to consolidate existing knowledge and identify research gaps, highlighting the critical role of Zn in supporting preterm infants' health. Further research is needed to establish evidence-based practices to improve health outcomes in this vulnerable population.

Phytonutrients in Breast Milk and Their Association with Maternal Dietary Intake: A Longitudinal Study in Adjamé

Carotenoids and flavonoids are essential nutrients for infant development. As for today, there is limited data on their availability in breast milk and the associated dietary factors, particularly in Côte d’Ivoire, where the diet of breastfeeding women is largely composed of cooked meals. The primary objective of this study was to determine the levels of carotenoids and flavonoids in breast milk using high-performance liquid chromatography (HPLC) during two lactation periods in Ivorian women who consumed two different diets. Mature breast milk samples were collected from healthy breastfeeding women on the 45th and 105th postpartum days. The mothers’ dietary frequencies were obtained using a questionnaire. A final sample of 60 breastfeeding women was selected. Two predominant basic diets were identified: cooked rice with palm nut sauce (R-SG) and attiéké with fried fish in refined palm oil accompanied by a paste of cooked vegetables (onion-red chili-fresh tomato) (A-PF). An overall increase in flavonoid levels was observed in all women’s milk on the 105th postpartum day, in contrast to carotenoid levels, where only the β-carotene content increased on the 105th day in the milk of women who consumed the R-SG diet (from 1.82 ± 0.30 µg/L to 2.13 ± 0.6 µg/L). The quercetin content in the milk of women on the A-PF diet (from 10.8 ± 1.6 µg/L to 19.98 ± 3.6 µg/L) significantly increased (p&amp;lt;0.05) compared to other flavonoids. Based on our results, consumption of cooked rice with palm nut sauce and attiéké with fried fish in refined palm oil accompanied by cooked vegetable sauce (onion-red chili-fresh tomato) increases the concentrations of quercetin, kaempferol, and epicatechin in milk. These findings can serve as dietary guidelines for breastfeeding mothers to improve β-carotene and flavonoid levels in breast milk, thus promoting infant growth and development.

TRNA-derived RNAs in human milk extracellular vesicles and associations with breastfeeding variables and maternal diet.

To describe tDRs in human milk EVs and their associations with maternal body mass index, age, dietary indices, breastfeeding frequency, season and time of milk collection in a Latina population. We sequenced small RNAs from EVs from 109 mature human milk samples collected at 1 month after delivery in the Southern California Mother's Milk Study. We grouped tDRs using hierarchical clustering and clusters were compared across tDR characteristics. We analyzed associations of tDRs with intrinsic maternal variables (body mass index, age), maternal nutrition (caloric intake, Healthy Eating Index, Dietary Inflammatory Index), and variables related to feeding and milk collection (breastfeeding frequency, season and time of milk collection) using negative binomial models. We identified 338 tDRs expressed in 90% or more of milk EV samples, of which 113 were identified in all samples. tDR-1:26-Gly-CCC-1-M4 accounted for most reads (79%). Pathway analysis revealed a wide array of biological processes and disease mechanisms across the four tDR clusters. tDRs were associated with season of collection, time of collection, breastfeeding frequency, and the dietary inflammatory index. tDRs are abundant in milk EVs and may be sensitive to maternal diet, seasonality, time of day, and breastfeeding frequency.

The Potential Applications of Natural Colostrum in Skin Health

Skin is a crucial organ for preserving the body’s equilibrium. Like other parts of the body, skin also ages due to extrinsic and intrinsic factors, leading to several signs such as wrinkles, spots, and a decline in elasticity, causing a range of issues similar to those seen elsewhere in the body. Some of these factors include ultraviolet (UV) radiation, hormonal disorders, genetic factors, loss of moisture, metabolic disorders, exposure to chemicals, and smoking. Colostrum, which is the initial foremilk, has shown positive effects on the consequences of these factors. Its content is richer than mature milk and contains several beneficial components. For instance, it includes hyaluronic acid, a molecule that binds water and keeps the skin hydrated; lactoferrin, with high antimicrobial properties; immunoglobulins, which are responsible for immunity; growth factors, which increase the amount of collagen, the main protein type of the skin; and, finally, the telomerase enzyme, which maintains the telomere’s length and, thus, decelerates the aging process. It has recently become apparent that using skin products with natural ingredients is essential. Considering its nature, contents, and effects, colostrum stands out as an excellent material for the cosmetic industry, especially for the aging sector. Therefore, the aim of this review article is to demonstrate the potential application of natural colostrum in skin health and its usage in natural cosmetic products in the cosmetic sector.

Non-Targeted Metabolomics of White Rhinoceros Colostrum and Its Changes During Early Lactation by 1H Nuclear Magnetic Resonance Spectroscopy.

Dynamic changes in components from colostrum to mature milk occur in any mammal. However, the time it takes to reach the mature milk stage differs between taxa and species, as do the final concentrations of all the components. The white rhinoceros belongs to the family Perissodactyla, of which the milk and milk metabolome of the domesticated Equidae have been studied to some detail. Metabolomic information on the colostrum and milk of the Rhinocerotidae is lacking. Colostrum and milk were obtained from seven white rhinoceroses. Of note is that it was their first parturition and all followed the same diet, two factors known to affect colostrum composition and its changes during early lactation in domesticated mammals. Milk serum was prepared by the ultrafiltration of the milk samples. Untargeted 1N NMR spectra were processed with Topspin 3.2, calibration was carried out according to the alanine signal and the identification of signals was carried out with Chenomx and assignments in the literature. Statistical analysis of the data was carried out using MetaboAnalyst 6.0. The changes in the metabolites were followed during the first 7 days of lactation as well as on day 20. The amounts of amino acids and their derivatives, organic acids and lipid metabolites decreased over lactation, while carbohydrates and their derivatives increased. The colostrum phase ended on day 2, while the transition to mature milk seemed to be complete by day 7. From day 3 to 7, galactose metabolism and tyrosine metabolism were uprated. Of interest is the presence of the oligosaccharide 3'-sialyllactose on days 3 and 4 of lactation. Mainly the content of carbohydrates increased over lactation, specifically lactose. The 3'-sialyllactose content peaked on days 3 and 4 of lactation. The colostrum phase ended on day 2. The mature milk stage was reached by day 7. The galactose metabolism and tyrosine metabolism were uprated after day 3 of lactation.

Does lactoferrin extracted from caprine colostrum has similar digestion and absorption pattern with that from caprine mature milk?

Lactoferrin (LF) plays crucial biological roles in infant growth and development. The differences in protein composition, structure, and glycosylation between colostrum and mature milk not only affect their biological functions but also alter their digestion and absorption properties through interactions with proteases. This study aimed to investigate the differences in the digestion and absorption properties between LF from caprine colostrum (CLF) and that from mature milk (MLF) by using in-vitro infant digestion model combined with Caco-2 cell model. CLF and MLF were relatively resistant to the gastric enzyme, however, they were degraded differently during intestinal digestion. CLF had higher hydrolysis degree (2.96%) and essential amino acids content (37.25%) after hydrolysis compared to MLF during intestinal digestion for 10 min (I10), but the reduction in all protein bands of CLF was less than MLF. At I10, CLF had a lower distribution of peptides smaller than 1000 kDa, accounting for 31.61%, while MLF had 40.18%. There were 404 common absorbed peptides in CLF and MLF but differed in abundance; Furthermore, 25 absorbed peptides with potential bioactive functions were identified in MLF and 9 were identified for CLF. Regarding the free amino acids, Ala, Asn, Asp, and Gly were absorbed more than CLF, with relatively higher mRNA levels of SLC6A19, SLC1A1, and PEPT1 than CLF. In addition, MLF significantly increased mRNA levels of Occludin, Claudin-2, Claudin-3, ZO-1, and ZO-2, suggesting better tight junction formation compared to CLF. These findings would have potential application in the infant formula improvement and new supplement development.

Analysis of the presence of natural killer cell subpopulations in preterm human milk: A first approach

Several immune cell populations are transferred to the newborn through breast milk, including natural killer (NK) cells, which are critical for innate defense and regulation of the immune response, especially in preterm infants. The aim of this study was to analyze the presence of NK cell subpopulations in different types of preterm breast milk. The study quantified the presence of NK cell subpopulations by flow cytometry using the relative expression of CD56 and CD16 markers in colostrum, transitional and mature milk samples from preterm mothers. Flow cytometry analysis revealed the presence of five NK cell subpopulations, but unlike those reported in peripheral blood, CD56dimCD16+ and CD56-CD16+ populations are predominantly present in preterm milk, only the CD56brightCD16dim population is increased in mature milk. Analysis of NK cell subpopulations in preterm milk revealed a pattern of NK cell presence in preterm breast milk with predominantly cytotoxic phenotypes in relation to CD16 marker expression.

The impact of cooling and Moringa supplementation on oxidative stress in serum and milk, including milk cytokines, in heat stressed lactating sows and their litters.

Heat stress (HS) poses a significant challenge to the United States swine industry. Sows and their piglets are particularly vulnerable to HS, as the periparturient phase is characterized by heightened metabolism and increased oxidative stress and inflammation. The study examined the effects of using conductive electronic cooling pads (ECP) and dietary supplementation with 4% Moringa (M) leaf powder on controlling oxidative stress and inflammation caused by HS in sows and their piglets. Forty-eight late gestation sows were assigned to four treatment groups: HS-fed corn-soybean meal (HS + CS), ECP-fed corn-soybean meal (ECP + CS), HS + M, and ECP + M. Blood was collected from sows on gestation (G) day 112, and lactation (L) day 14 and L20, and from piglets (2 males and 2 females) in each litter on postnatal (PN) day 1 and PN20. Colostrum was collected within 2h of birth of the first neonate, and mature milk was collected on L14. Piglet fecal samples were collected on PN14 to measure calprotectin concentration as a marker of intestinal inflammation. Biological antioxidant potential (BAP), derivatives of reactive oxygen metabolites (dROMs). and oxidative stress index (OSi) were measured in blood and milk samples using a Free Radical Elective Evaluator. Milk samples pooled by day of lactation and treatment group were analyzed using cytokine array. Levels of inflammatory cytokines in colostrum were affected by Moringa supplementation and cooling, but not mature milk. Notably, the anti-inflammatory cytokines interleukin (IL)-10 and IL-1ra were 2.14 and 1.57 Log2 higher in the colostrum of HS + M compared to other groups. The OSi of colostrum was higher (P = 0.0002) than mature milk. Level of BAP in sow serum was greater in ECP + CS and HS + M (P = 0.0291) compared to other groups. Moringa had an overall effect of increasing dROMs (P = 0.0035) and levels of OSi were lowest in ECP + CS (P = 0.0296) sow serum. Treatments did not affect piglet serum oxidative index (P > 0.05) or calprotectin levels (P > 0.05). Findings support further studies to investigate the efficacy of using ECP and Moringa supplementation to mitigate inflammation and oxidative stress imposed by heat stress conditions in lactating sows.