Catalina Amadora Pomar

We aimed to evaluate the effects of maternal diet and betaine supplementation during the suckling period on Fgf21 expression and metabolic pathways related to FGF21 signaling and metabolic programming. Offspring of Wistar rats fed either a chow diet (CD) or a Western diet (WD) were studied at postnatal day 22 and at 7 months. During suckling, pups received betaine at a physiological dose corresponding to twice the average intake estimated from milk consumption, or a vehicle. After weaning onto a CD, all animals were switched to a WD from months four to seven. Biometric parameters, circulating markers, and gene expression in hypothalamus, retroperitoneal white adipose tissue (rWAT), and liver were analyzed, together with cecal Akkermansia muciniphila abundance. At day 22, a maternal WD reduced hepatic Fgf21 expression in both sexes; however, only males showed decreased Klb expression in rWAT, consistent with impaired FGF21 signaling. A maternal WD also reduced A. muciniphila abundance. Betaine increased Fgfr1 expression in rWAT of female offspring from control dams. By seven months, betaine supplementation in males born to WD dams increased adiposity, and insulin and leptin levels, whereas females exhibited an improved plasma lipid profile (lower NEFA and TG). Hypothalamic Drd2 and Fgfr1 expression further showed sex‐specific modulation by the maternal diet and betaine. In conclusion, betaine supplementation during suckling exerts sex‐specific long‐term effects on metabolic programming. Females showed an improved lipid profile, whereas males, particularly those exposed to a maternal WD, developed increased adiposity and altered endocrine profiles. The findings suggest that early‐life betaine supplementation can modulate long‐term metabolic outcomes through sex‐specific effects on FGF21‐related pathways.

Perinatal nutrition influences offspring metabolic phenotype and obesity risk. This study examines how a maternal obesogenic diet and offspring's leptin supplementation during suckling affect the metabolome in offspring adulthood, offering insights into long‐term metabolic programming. Offspring of dams fed a standard diet (SD), a Western‐style diet (WD) before and during gestation and lactation (WD‐dams), or a WD switched to SD during lactation were supplemented throughout suckling with leptin or vehicle and then maintained on an SD post‐weaning. Metabolomic analysis of plasma from offspring adult animals revealed sex‐specific alterations in the relative abundance of circulating metabolites due to maternal WD. Among these, lower abundance of orotic acid in males and arginine in females emerged as the most discriminating metabolites between experimental groups influenced by maternal WD during gestation and lactation. These changes, indicative of poor metabolic programming, were largely normalized by dietary intervention during lactation. Leptin supplementation during suckling also induced favorable metabolic adaptations, reflected in lower N ‐acetylneuraminic acid and choline abundance (both sexes), higher 5‐amino valeric acid betaine (males), lower TCA cycle intermediates (fumarate, succinate, malate), and elevated γ‐glutamyl peptides (γ‐glutamylalanine, γ‐glutamylglutamine) (females), suggesting potential anti‐inflammatory effects. These findings enhance our understanding of how early‐life conditions influence long‐term metabolism and underscore the potential of circulating metabolites as biomarkers for assessing perinatal interventions.

Breast milk provides a wide range of nutritional and bioactive components crucial for infant growth and development during lactation, ultimately influencing future health outcomes. Here, we used untargeted metabolomics to identify differences in the breast milk metabolome related to maternal overweight/obesity and diet, assessing their influence on infant weight gain in the first month of lactation. Anthropometric data from 52 lactating mother–infant pairs were collected at birth and 1 month postpartum, along with breast milk samples. Information about food consumed the day before milk sampling (24‐h questionnaire) was collected, and a food frequency questionnaire was completed. Our findings reveal that mothers with overweight/obesity had greater lactose levels (p = 0.025) and lower levels of orotic acid (p = 0.002), 3‐indoxyl sulfate (p = 0.027), heneicosanoic acid (p = 0.040), and N1‐methylguanosine (p = 0.046) in milk than normal‐weight mothers. Notably, reduced orotic acid levels were associated with a greater infant weight gain during this period. Furthermore, mothers with a low adherence to the Mediterranean diet showed lower levels of citric acid (p = 0.041), N6‐succinyladenosine (p = 0.043), uric acid (p = 0.034), and eicosenoic acid (p = 0.035), and higher levels of acylcarnitine C6:0 (p = 0.041) than mothers with a medium/high adherence. Besides orotic acid, other milk metabolites were related to infant weight gain during this period, with maternal fruit and fish consumption (p = 0.015 and p = 0.017) emerging as the most influential dietary factor for an adequate early infant growth trajectory. None of the metabolites identified remained statistically significant after multiple‐comparisons adjustment. Present results, showing how maternal diet and obesity can affect breast milk metabolites and infant growth, offer insights to improve lactation‐feeding practices and support healthy infant development.

This study investigates the impact of maternal nutrition during lactation on inflammation and oxidative stress in the offspring of diet-induced obese rats, along with the potential benefits of leptin supplementation during suckling. Dams were fed either a standard diet (SD), a western diet (WD) before and during gestation and lactation (WD-dams), or a WD switched to an SD during lactation (Rev-dams). Offspring were supplemented with leptin or vehicle during suckling and then fed an SD or WD until four months. Offspring of the Rev-dams exhibited improved metabolic indicators, including lower body weight, reduced plasma levels of TNF-alpha, a higher adiponectin/leptin (A/L) ratio, enhanced liver antioxidant defenses, and decreased inflammation markers in white adipose tissue (WAT) compared to WD-dams, with sex differences. Leptin supplementation further modulated these markers, reducing oxidative stress in liver and inflammation in WAT and liver (e.g., hepatic Tnfa expression decreased by 45% (males) and 41% (females) in the WD group on an SD), and improving the A/L ratio, with effects varying by maternal conditions and sex. In conclusion, this study underscores the importance of maternal nutrition and leptin intake during suckling in shaping long-term metabolic and inflammatory health in offspring, offering strategies to mitigate the adverse effects of maternal obesity on future generations.

Early life conditions may influence the gut microbiome and contribute to health status in adulthood. We examined the impact of maternal obesity and/or obesogenic diet on the gut microbiome of mothers (at weaning) and their adult offspring, along with the effects of leptin supplementation during suckling. Three groups of rats were studied: control (C) dams, fed with standard diet (SD); western diet (WD) dams, fed with WD (a high‐fat, high‐sucrose diet) before gestation and during gestation and lactation; and reversion (REV) dams, fed as WD‐dams but with SD during lactation. Offspring were supplemented throughout suckling with leptin/vehicle and weaned on an SD. WD‐dams showed lower microbial diversity and an altered microbiome compared to C‐ and REV‐dams, widely normalized by diet improvement during lactation. WD‐ and REV‐offspring (males) displayed lower microbiome diversity and greater dominance compared to C‐offspring. Taxonomic group differences (Proteobacteria phylum and Bacteroides, Parasutterella, and Phocea genera) were observed in WD‐ and REV‐offspring. WD‐offspring, but not REV‐offspring, had a greater abundance of the phylum Firmicutes and Lachnospiraceae family and a lower abundance of the family Tannerellaceae compared to C‐offspring. Leptin supplementation led to decreased abundance of the phylum Actinobacteria (family Eggerthellaceae and genera Enterorhabdus and Adlercreutzia (females)), and the genera Lachnospiraceae UCG‐008 group, Roseburia and Limosilactobacillus, and increased abundance of the genus Dellaglioa, compared to vehicle‐treated groups. Therefore, maternal consumption of an obesogenic diet during the perinatal period results in microbiome changes in dams, alleviated by dietary improvement during lactation. Maternal conditions and leptin supplementation during suckling modestly influenced the microbiome in adulthood, which might partially contribute to the adverse/beneficial effects, respectively, of these conditions on programmed metabolic health.

We aimed to evaluate whether improving maternal diet during lactation in diet‐induced obese rats reverts the impact of western diet (WD) consumption on the metabolome of milk and offspring plasma, as well as to identify potential biomarkers of these conditions. Three groups of dams were followed: control‐dams (CON‐dams), fed with standard diet (SD); WD‐dams, fed with WD prior and during gestation and lactation; and reversion‐dams (REV‐dams), fed as WD‐dams but moved to SD during lactation. Metabolomic analysis was performed in milk at lactation days 5, 10, and 15, and in plasma from their male and female offspring at postnatal day 15. Milk of WD‐dams presented, throughout lactation and compared to CON‐dams, altered profiles of amino acids and of the carnitine pool, accompanied by changes in other polar metabolites, being stachydrine, N‐acetylornithine, and trimethylamine N‐oxide the most relevant and discriminatory metabolites between groups. The plasma metabolome profile was also altered in the offspring of WD‐dams in a sex‐dependent manner, and stachydrine, ergothioneine and the acylcarnitine C12:1 appeared as the top three most discriminating metabolites in both sexes. Metabolomic changes were largely normalized to control levels both in the milk of REV‐dams and in the plasma of their offspring. We have identified a set of polar metabolites in maternal milk and in the plasma of the offspring whose alterations may indicate maternal intake of an unbalanced diet during gestation and lactation. Levels of these metabolites may also reflect the beneficial effects of implementing a healthier diet during lactation.

We aimed to analyze the long-term metabolic effects of leptin supplementation at physiological doses during suckling in the offspring of diet-induced obese rats, together with the potential benefits of improving maternal diet during lactation. Thus, the offspring of: dams fed standard-diet (SD) (CON-dams), dams fed western-diet (WD) before and during gestation and lactation (WD-dams), and dams fed as WD-dams but moved to SD during lactation (REV-dams) were supplemented throughout suckling with leptin or vehicle, and fed SD or WD from weaning to four months. Under SD, leptin treatment significantly improved metabolic profile and body fat accumulation, with stronger effects in the male offspring of CON-dams and REV-dams. Under WD, the offspring of WD-dams presented metabolic alterations that were not evident in the offspring of REV-dams. Moreover, leptin supplementation improved glucose homeostasis in the male offspring of REV-dams. Conversely, leptin supplementation in females born to WD-dams and fed WD from weaning resulted in impaired insulin sensitivity and increased hepatic lipid content. These results highlight the importance of a balanced maternal diet during the perinatal period, especially lactation, for the subsequent metabolic health of the offspring and for the beneficial effects of leptin supplementation during suckling, more evident in the male offspring.

Increased miR‐222 levels are associated with metabolic syndrome, insulin resistance, and diabetes. Moreover, rats fed an obesogenic diet during lactation have higher miR‐222 content in breast milk and the offspring display greater body fat mass and impaired insulin sensitivity in adulthood. In order to investigate the molecular mechanisms involved and to dissect the specific effects of miR‐222 on adipocytes, transfection with a mimic or an inhibitor of miR‐222 has been conducted on 3T3‐L1 preadipocytes. 3T3‐L1 cells were transfected with either a mimic or an inhibitor of miR‐222 and collected after 2 days (preadipocytes) or 8 days (mature adipocytes) for transcriptomic analysis. Results showed a relevant impact on pathways associated with insulin signaling, lipid metabolism and adipogenesis. Outcomes in key genes and proteins were further analyzed with quantitative reverse transcription polymerase chain reaction and Western Blotting, respectively, which displayed a general inhibition in important effectors of the identified routes under miR‐222 mimic treatment in preadipocytes. Although to a lesser extent, this overall signature was maintained in differentiated adipocytes. Altogether, miR‐222 exerts a direct effect in metabolic pathways of 3T3‐L1 adipocytes that are relevant to adipocyte function, limiting adipogenesis and insulin signaling pathways, offering a mechanistic explanation for its reported association with metabolic diseases.

Gene expression patterns in blood cells from SARS-CoV-2 infected individuals with different clinical phenotypes and body mass index (BMI) could help to identify possible early prognosis factors for COVID-19. We recruited patients with COVID-19 admitted in Hospital Universitari Son Espases (HUSE) between March 2020 and November 2021, and control subjects. Peripheral blood cells (PBCs) and plasma samples were obtained on hospital admission. Gene expression of candidate transcriptomic biomarkers in PBCs were compared based on the patients’ clinical status (mild, severe and critical) and BMI range (normal weight, overweight, and obesity). mRNA levels of ADAM17, IFITM3, IL6, CXCL10, CXCL11, IFNG and TYK2 were increased in PBCs of COVID-19 patients (n = 73) compared with controls (n = 47), independently of sex. Increased expression of IFNE was observed in the male patients only. PBC mRNA levels of ADAM17, IFITM3, CXCL11, and CCR2 were higher in those patients that experienced a more serious evolution during hospitalization. ADAM17, IFITM3, IL6 and IFNE were more highly expressed in PBCs of patients with obesity. Interestingly, the expression pattern of ADAM17, IFITM3 and IFNE in PBCs was related to both the severity of COVID-19 evolution and obesity status, especially in the male patients. In conclusion, gene expression in PBCs can be useful for the prognosis of COVID-19 evolution.

Scope: This study aims to assess in rats whether normalizing maternal diet during lactation prevents the harmful effects of western diet (WD) consumption during the whole perinatal period on the lipidomic profile in maternal milk and offspring plasma.Methods and Results: Control dams (CON‐dams), fed with standard diet (SD); WD‐dams, fed with WD prior and during gestation and lactation; and reversion dams (REV‐dams), fed as WD‐dams but moved to SD during lactation are followed. Lipidomic analysis is performed in milk and plasma samples from pups. Milk of WD‐dams presents a different triacylglycerol composition and free fatty acid (FA) profile compared to CON‐dams, including an increased ratio of pro‐inflammatory to anti‐inflammatory long‐chain polyunsaturated FA. Such alterations, which are also present in the plasma of their offspring, are widely reversed in the milk of REV‐dams and the plasma of their pups. This is related with the recovery of control adiponectin expression levels in the mammary gland, and the presence of decreased expression of pro‐inflammatory factors.Conclusion: Implementing a healthy diet during lactation prevents early alterations in the plasma lipidome of pups associated to the maternal intake of an obesogenic diet, which may be related to the normalization of milk lipid content and the inflammatory state in the mammary gland.