Search Results (79)

Introduction: Human breast milk (HBM) is a critical source of nourishment for newborns, containing bioactive compounds that influence infant growth and metabolic programming. Among these compounds, leptin—a hormone primarily produced by adipocytes but also synthesized in the mammary gland—has gathered attention for its potential role in regulating energy balance and body weight. This study investigates the influence of maternal factors on HBM leptin concentrations and explores their associations with neonatal growth parameters. Material and Methods: 262 HBM samples were collected from healthy lactating mothers through Spanish Biobanks during the first six months postpartum. Data on maternal characteristics (body mass index (BMI), age, physical activity, parity, and delivery type) and neonatal measurements (weight, length, and head circumference) were collected. Leptin concentrations in skimmed HBM were measured using the ELISA technique (R&D Systems™, Minneapolis, MN, USA). Statistical analyses were conducted using R version 4.3.1 and MATLAB R2023a, with significance set at p < 0.05. Results: Leptin levels were highest in and declined over time, reaching a stable level after the first month of lactation. Preterm deliveries exhibited significantly higher leptin concentrations than term deliveries (0.42 vs. 0.07 ng/mL). Higher leptin levels were also observed in younger and primiparous mothers. Maternal BMI was positively associated with leptin concentration, with mothers who had elevated BMI showing higher levels than those with optimal BMI (0.36 vs. 0.05 ng/mL). Maternal physical activity was not associated with leptin concentrations in univariate analyses; although greater self-reported physical activity appeared associated with lower leptin concentrations in regression models, this finding should be interpreted cautiously and should not be considered evidence of an independent or consistent effect. Neonatal growth parameters (weight, length, and head circumference) were negatively correlated with HBM leptin concentrations. Conclusions: Our findings indicate that leptin levels in breast milk reflect both maternal metabolic status and neonatal characteristics and may represent a compensatory mechanism in preterm infants. HBM leptin levels are modulated by maternal BMI, age, parity, and delivery type, and are associated with neonatal growth parameters. Full article

Negative energy balance (NEB) during early lactation links spontaneous lipolysis (SL) with inflammatory signaling, yet the molecular response in dual-purpose breeds remains insufficiently characterized. This study investigated how NEB regulates circulating concentrations of interleukin-6 (IL-6) and plasminogen (PL) in Simmental cows, contextualizing these changes within concurrent metabolic adaptation. Forty-two cows were monitored from approximately two weeks prepartum to 150 days in milk across six defined stages. Energy balance (EB) was calculated from feed intake and energy-corrected milk yield, while daily milk production (DMP), milk composition, body condition score (BCS), β-hydroxybutyrate (BHBA), glucose (GLU), leptin (LEP), selected fatty acids (FAs: C16:0, C18:0, C18:1-t9, C18:2, IL-6), and PL were determined. EB declined progressively as DMP increased (r = −0.689, p ≤ 0.05). During peak NEB (SLII–SLIII), IL-6 increased from 92.16 to 109.59 ng·L⁻¹ and PL from 1.65 to 2.05 ng·L⁻¹, both inversely correlated with EB (r = −0.741 and −0.586, respectively) and positively associated with each other (r = 0.728), indicating coordinated activation of cytokine and fibrinolytic pathways. NEB severity was accompanied by elevated BHBA and LEP, decreased GLU, reduced BCS, and increased circulating FAs; nevertheless, ketosis remained moderate (peak BHBA 1.04 mmol·L⁻¹). These findings demonstrate that Simmental cows display a breed-specific molecular response in which NEB modulates IL-6 and PL in parallel with controlled lipid mobilization and efficient hepatic metabolism, supporting enhanced metabolic resilience during early lactation. Full article

Maternal overweight and obesity have reached global epidemic levels, altering metabolic adaptations during pregnancy and lactation. Beyond their well-known impact on gestational outcomes, elevated BMI profoundly influences the secretion of adipokines—hormones derived from adipose tissue that circulate in maternal blood and are secreted into breast milk—thereby directly linking maternal metabolism to offspring development. In this state-of-the-art narrative review, we synthesize current evidence on how maternal overweight and obesity shape concentrations of key adipokines (leptin, adiponectin, ghrelin, obestatin, and resistin) in serum, cord blood and breast milk. Excess maternal weight robustly increases leptin, while effects on adiponectin, ghrelin, obestatin, and resistin remain uncertain. To our knowledge, this is the first review to focus specifically on the impact of maternal overweight and obesity on adipokine alterations across both pregnancy and lactation. Future studies should apply standardized sampling and analytical protocols and use longitudinal designs including body composition assessments to clarify their role in maternal and child metabolic health. Full article

This review synthesizes advances in livestock genomics by examining the interplay between candidate genes, molecular markers (MMs), signatures of selection (SSs), and quantitative trait loci (QTLs) in shaping economically vital traits across livestock species. By integrating advances in genomics, bioinformatics, and precision breeding, the study elucidates genetic mechanisms underlying productivity, reproduction, meat quality, milk yield, fibre characteristics, disease resistance, and climate resilience traits pivotal to meeting the projected 70% surge in global animal product demand by 2050. A critical synthesis of 1455 peer-reviewed studies reveals that targeted genetic markers (e.g., SNPs, Indels) and QTL regions (e.g., IGF2 for muscle development, DGAT1 for milk composition) enable precise selection for superior phenotypes. SSs, identified through genome-wide scans and haplotype-based analyses, provide insights into domestication history, adaptive evolution, and breed-specific traits, such as heat tolerance in tropical cattle or parasite resistance in sheep. Functional candidate genes, including leptin (LEP) for feed efficiency and myostatin (MSTN) for double-muscling, are highlighted as drivers of genetic gain in breeding programs. The review underscores the transformative role of high-throughput sequencing, genome-wide association studies (GWASs), and CRISPR-based editing in accelerating trait discovery and validation. However, challenges persist, such as gene interactions, genotype–environment interactions, and ethical concerns over genetic diversity loss. By advocating for a multidisciplinary framework that merges genomic data with phenomics, metabolomics, and advanced biostatistics, this work serves as a guide for researchers, breeders, and policymakers. For example, incorporating DGAT1 markers into dairy cattle programs could elevate milk fat content by 15-20%, directly improving farm profitability. The current analysis underscores the need to harmonize high-yield breeding with ethical practices, such as conserving heat-tolerant cattle breeds, like Sahiwal. Full article

Obesity is a multifactorial condition that influences metabolic, endocrine, inflammatory, circadian, and behavioral systems. These disruptions can adversely affect the initiation of lactogenesis II—the critical process marking the onset of copious milk secretion following childbirth. In mothers with obesity, prolonged inflammation within the mammary gland, a blunted hormonal response (notably of prolactin), altered progesterone and estrogen dynamics, high leptin levels, and misaligned circadian rhythms contribute significantly to delayed lactogenesis. In addition, mechanical difficulties and psychological factors further hinder effective breastfeeding. This report synthesizes evidence from human epidemiological studies and animal models that elucidate the diverse mechanisms linking maternal obesity to delayed lactogenesis. We review the role of obesity-associated inflammatory mediators in impairing mammary tissue remodeling, the endocrine aberrations that impair lactogenic signaling, the consequences of circadian disruption on hormonal rhythmicity, and the behavioral influences that challenge effective breastfeeding. Finally, we discuss the clinical implications of these findings and propose future research directions targeting endocrine modulation, anti-inflammatory therapy, circadian interventions, and enhanced lactation support strategies for mothers with obesity. Full article

Background: Almond milk is often seen as a healthier alternative to cow milk. However, its effect on postprandial glycemia compared to 2% milk is unclear. Here, we compared the postprandial glycemic effect of almond milk versus carbohydrate- or caloric-matched 2% milk, each served with oatmeal to patients with type 2 diabetes (T2D). Methods: In this crossover, three-way, open-label study, 22 participants (mean age 66 ± 7.4 years, 36% female), with T2D and overweight or obesity, consumed oatmeal served with almond milk (ALM), carbohydrate-matched 2% milk (MLKCRB), or calorie-matched 2% milk (MLKCAL) on separate days and in a random order. The primary outcome was glucose incremental area under the curve for 240 min (iAUC0-240). The secondary outcomes included postprandial serum insulin, glucagon, plasma free fatty acids (FFAs), serum triglycerides, leptin, and gastrointestinal hormones (PYY, active GLP-1, GIP, amylin, cholecystokinin, and ghrelin). Results: We did not find any difference in either the primary endpoint or secondary endpoints between the three groups. However, iAUC0-240 for insulin and glucagon was significantly higher in MLKCRB vs. ALM (FDR = 0.002 and 0.02, respectively). Conclusions: Almond milk does not offer any additional glycemic benefit over 2% milk and does not differ in its postprandial effects on FFAs, serum triglycerides, leptin, and gastrointestinal hormones over 4 h. Nonetheless, carbohydrate-matched 2% milk elicited greater insulin and glucagon response compared to almond milk, warranting further investigation into its long-term implications. Full article

Background/Objectives: Endocannabinoids are endogenous bioactive lipids that promote neurodevelopment and positive energy balance. Increased levels of endocannabinoids are associated with obesity, but the effect of maternal obesity on breast milk endocannabinoids across lactation is mostly unknown. Methods: Women from Rio de Janeiro (Brazil) (n = 92) were followed from the third trimester of pregnancy to 119 days postpartum, and milk samples were analyzed in the postpartum days 2–8 (T1), 28–47 (T2), and 88–119 (T3). We assessed the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) by high-performance liquid chromatography–mass spectrometry, leptin and insulin by immunoassay, and macronutrients by colorimetric assays in milk samples. Results: Milk AEA concentration was higher in T2 compared with T1 or T3, while 2-AG levels were higher in T2 and T3 compared with T1. Milk endocannabinoids were directly correlated with pre-pregnancy body mass index (BMI), gestational weight gain (GWG), and milk triglycerides. Triglyceride and leptin levels were higher in mature milk (T2 and T3) of women with BMI > 25 or excessive GWG. Adjusted linear regression models showed a positive association between excessive GWG and milk 2-AG (β = 1629; 95% CI: 467–2792; p = 0.008). Conclusions: The endocannabinoid levels are higher in mature milk from women with obesity or excessive GWG, which may impact offspring development and metabolism. Full article

Adequate milk production is key for optimal infant growth, yet women often wean due to perceived low milk production (LMP). Maternal adiposity and gestational diabetes mellitus (GDM) are known potential risk factors for LMP and may alter both hormonal and macronutrient composition of human milk. This study aims to investigate the hormonal and macronutrient composition of human milk in relation to LMP, particularly in the context of maternal adiposity and GDM. Human milk samples were collected from 68 women with LMP and 160 women with normal milk production during 1–6 months postpartum. Of the 228 participants with the mean pre-pregnancy BMI of 26.3 ± 6.0 kg/m², 80 (35.1%) had GDM. Concentrations of hormones (estrone, estradiol, progesterone, insulin, leptin, adiponectin) and macronutrients (fat, protein, lactose, glucose) were measured and compared between the two groups. Univariable and multivariable logistic regression analyses were conducted, adjusting for potential confounders such as maternal body mass index (BMI) and GDM, to assess the relationships between hormone and macronutrient concentrations, and milk production. Preliminary analyses indicated that higher concentrations of estrone (p < 0.001), leptin (p = 0.009), insulin (p = 0.002), protein (p = 0.012), and lactose (p = 0.004) were associated with LMP. After adjusting for maternal BMI and GDM in the univariable models, all of these associations remained, and progesterone (p = 0.045) also emerged as positively associated with LMP. In multivariable regression, followed by stepwise model selection, estrone (p < 0.001), protein (p < 0.001) and lactose (p = 0.015) demonstrated the strongest associations with LMP, with maternal BMI also contributing significantly (p = 0.010). The findings suggest that hormone and macronutrient concentrations in human milk may reflect LMP status and provide insights into the underlying biological mechanisms associated with LMP. Full article

Human milk (HM) is a complex biofluid rich in nutrients and bioactive compounds essential for infant health. Recent advances in omics technologies—such as proteomics, metabolomics, and transcriptomics—have shed light on the influence of HM on bone development and health. This review discusses the impact of various HM components, including proteins, lipids, carbohydrates, and hormones, on bone metabolism and skeletal growth. Proteins like casein and whey promote calcium absorption and osteoblast differentiation, supporting bone mineralization. Long-chain polyunsaturated fatty acids like docosahexaenoic acid (DHA) contribute to bone health by modulating inflammatory pathways and regulating osteoclast activity. Additionally, human milk oligosaccharides (HMOs) act as prebiotics, improving gut health and calcium bioavailability while influencing bone mineralization. Hormones present in HM, such as insulin-like growth factor 1 (IGF-1), leptin, and adiponectin, have been linked to infant growth, body composition, and bone density. Research has shown that higher IGF-1 levels in breast milk are associated with increased weight gain, while leptin and adiponectin influence fat mass and bone metabolism. Emerging studies have also highlighted the role of microRNAs (miRNAs) in regulating key processes like adipogenesis and bone homeostasis. Furthermore, microbiome-focused techniques reveal HM’s role in establishing a balanced infant gut microbiota, indirectly influencing bone development by enhancing nutrient absorption. Although current findings are promising, comprehensive longitudinal studies integrating omics approaches are needed to fully understand the intricate relationships among maternal diet, HM composition, and infant bone health. Bridging these gaps could offer novel dietary strategies to optimize skeletal health during infancy, advancing early-life nutrition science. Full article

Objective: We investigated whether the results of leptin gene (LEP) 2548G/A (rs7799039) and leptin receptor gene (LEPR) 668 A/G (rs1137101) variants, as well as the methylation analysis of CpG regions at nucleotides −31 and −51 of the LEP gene, showed any differences between breastfed and non-breastfed children in this study. Materials and Methods: The cross-sectional study included 100 children aged 2–5 years who were attending nursery and kindergarten and had been accepted to the Department of General Paediatrics. Infants who were exclusively breastfed for the first six months after birth constituted the study group, and those who were not only breastfeed constituted the control group. Methylation percentages at CpG islands of the LEP gene were compared between exclusively breastfed and non-exclusively breastfed infants, and the statistical significance was analyzed by looking for changes in LEP −31 and −51 nt methylation and LEP 2548G/A ve LEPR 668 A/G variants. Results: Both groups were compared by feeding, and the association of LEPR and LEP gene polymorphisms and −51 nt and −31 nt methylations were analyzed. There were no significant differences between the groups regarding genotype and allele frequency for the LEPR 668 A/G, LEP 2548 G/A gene variant, −31 nt methylation, and −51 nt methylation status. Similarly, there was no significant difference in genotype and allele frequency for the LEPR 668 A/G gene variant in terms of duration of exclusive breastfeeding, total breastfeeding, body mass index, family obesity, and satiety status. However, maternal support from family elders and physical activity increased the 51 nt methylation, but this methylation was not significantly affected by BMI, age, or satiety status. Conclusions: Maternal support from family elders and physical activity were associated with increased 51 nt methylation, but this methylation was not significantly affected by BMI, age, or satiety status. However, there are not enough studies in this area to reach a definitive conclusion, and further research is needed. Full article

Human milk comprehensively meets the nutritional needs of a child, providing not only structural and energy components but also various bioactive factors. Among these, neurotrophic factors and hormones involved in metabolic processes deserve special attention. Studies using enzyme-linked immunosorbent assays compared the content of neurotrophic factors—CNTF, NT-3, and NGF—and hormones, leptin and insulin, in two groups of breast milk samples: early lactation (1–3 months) and extended lactation (>6 months, up to 12 months). The results indicated changes in leptin and insulin levels as the lactation period extended. NGF, leptin, and insulin were present in milk samples from both study groups, with leptin and insulin levels being higher in the early lactation group. CNTF and NT-3 were not detected in any of the samples from either study group. The analyses confirmed that human milk from women who breastfeed for extended periods remains a source of biologically active components and macronutrients that support a child’s development and health. Full article

Background/Objectives: The negative energy balance activaties of spontaneous lipolysis. This may promotes inflammation within the adipose tissue. The aim of the study was to explain the development of inflammation during increased lactogenesis. It was hypothesized that lipolysis contributes synthesis of interleukin-6 and plasminogen. Methods: The study was in production conditions carried out using Holstein-Friesian cows. The period studied covered time of early lactation. Results: Up to the peak of lactation, milk yield strongly influenced the rate of loss of body condition. This had an impact on with the intensity of the release of the fatty acids. In both cases this relationships strengthened to the peak of production. Oobserved tendencies towards a decrease in the concentration of glucose and an increase in that of leptin. Loss of the body condition and the release of NEFA were were influencing to affect the blood concentrations of interleukin-6 and plasminogen. We have shown that IL-6 has a relatively strong correlation with the NEFA. They correlate with IL-6 independently of EB influence. This may suggest independent associations between these variables, which could potentially be applied in practice. Conclusions: The NEFA release in the long term can increase the inflammatory response within adipose tissue and can intensify the release of interleukin-6 and plasminogen. It is likely that in the initial stage of lactogenesis, the inflammatory process developing within adipose tissue is physiologically justified. Our results can provide background to this little-described area of research. Full article

Leptin (LEP), a protein hormone well-known for its role in metabolic regulation, has recently been linked to lipid metabolism in cattle. However, its function in buffalo mammary glands remains unclear. To address this issue, we isolated and identified the LEP gene and conducted experiments to investigate its function in buffalo mammary epithelial cells (BuMECs). In this study, two transcript variants of LEP, designated as LEP_X1 and LEP_X2, were identified. The coding sequences (CDS) of LEP_X1 and LEP_X2 are 504 bp and 579 bp in length, encoding 167 and 192 amino acid residues, respectively. Bioinformatics analysis revealed that LEP_X2 is a hydrophobic protein with an isoelectric point below 7 and contains a signal peptide, while LEP_X1 is hydrophilic and lacks a signal peptide. Our study found that LEP gene expression in lactating BuMECs was significantly higher than in non-lactating cells, with LEP_X2 expression remarkably higher than LEP_X1 in lactating BuMECs. Overexpression of both LEP_X1 and LEP_X2 significantly promoted the expression of genes related to milk fat synthesis in lactating BuMECs, including STAT3, PI3K, mTOR, SCD, and SREBF1, accompanied by an increase in cellular triglycerides (TG). Interestingly, LEP_X2 overexpression significantly suppressed LEP_X1 expression while increasing intracellular TG concentration by 12.10-fold compared to LEP_X1 overexpression, suggesting an antagonistic relationship between the two variants and supposing LEP_X2 plays a dominant role in milk fat synthesis in lactating BuMECs. Additionally, four nucleotide substitutions were identified in the buffalo LEP CDS, including a nonsynonymous substitution c.148C>T (p.Arg50Cys), which was predicted to decrease the stability of the LEP protein without affecting its function. These results collectively underscore the significant role of LEP in milk fat synthesis and can provide a basis for molecular breeding strategies of buffalo. Full article

Human milk (HM) composition, including metabolic hormones and lipids, is influenced by various factors, including lactation stage and, potentially, infant sex, which may affect infant body composition (BC) development. We aimed to: (a) characterize the longitudinal concentration and intake profiles of HM leptin, adiponectin, insulin, and total lipids; (b) determine if their concentrations and intakes differ by infant sex; and (c) explore the intakes relationships with the development of infant BC. Milk samples (n = 501) were collected from 82 mother–infant dyads during the first 6 months postpartum. Infant 24 h HM intake was measured, and the average cumulative HM component intakes were calculated. The statistical analysis used linear mixed modeling. Intakes of HM leptin, adiponectin, insulin, and total lipids increased to 1 month postpartum and then remained stable. HM intake and total lipids intake but not hormone intakes were positively associated with infant BC (fat-free mass, fat-free mass index, fat mass, fat mass index, percentage fat mass, and fat mass to fat-free mass ratio). HM component concentrations and intakes did not differ by sex. These findings advance our understanding of the temporal nature of HM components, emphasizing the role of infant 24 h HM and total lipids intake in development of infant lean and adipose tissue. Full article

The early stages of life, especially the period from conception to two years, are crucial for shaping metabolic health and the risk of obesity in adulthood. Adipose tissue (AT) plays a crucial role in regulating energy homeostasis and metabolism, and brown AT (BAT) and the browning of white AT (WAT) are promising targets for combating weight gain. Nutritional factors during prenatal and early postnatal stages can influence the development of AT, affecting the likelihood of obesity later on. This narrative review focuses on the nutritional programming of AT features. Research conducted across various animal models with diverse interventions has provided insights into the effects of specific compounds on AT development and function, influencing the development of crucial structures and neuroendocrine circuits responsible for energy balance. The hormone leptin has been identified as an essential nutrient during lactation for healthy metabolic programming against obesity development in adults. Studies have also highlighted that maternal supplementation with polyunsaturated fatty acids (PUFAs), vitamin A, nicotinamide riboside, and polyphenols during pregnancy and lactation, as well as offspring supplementation with myo-inositol, vitamin A, nicotinamide riboside, and resveratrol during the suckling period, can impact AT features and long-term health outcomes and help understand predisposition to obesity later in life. Full article