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Lopez-Tello, J.

Publications and source records attributed to Lopez-Tello, J..

8 recordsLinked to original sources

Placental lipid handling, growth and inflammatory pathways are modified by a maternal Mediterranean diet

AimsThe Mediterranean diet is associated with reduced cardiometabolic risk, yet its physiological effects during pregnancy and its impact on placental metabolism remain incompletely understood. This study aimed to determine whether maternal adherence to a Mediterranean diet during pregnancy influences placental lipid metabolism and signalling pathways involved in nutrient handling, tissue remodelling, and inflammation, and to assess their relationship with pregnancy outcomes. MethodsPlacental samples and clinical outcome data were analysed from pregnant women participating in an unblinded randomized clinical trial of a Mediterranean diet intervention. Placental lipid composition was quantified and the expression of genes and signalling pathways involved in lipid metabolism, nutrient transport, inflammation, and tissue remodelling was evaluated. ResultsMaternal adherence to a Mediterranean diet during pregnancy was associated with significant alterations in placental lipid composition, including reduced C18:0 and C24:0 and increased C18:1n9c, C20:3n6, and C22:0, with lower total short-chain fatty acids and higher monounsaturated fatty acids. Placental expression of lipid metabolism regulators ALOX15 and PPAR{gamma} was reduced, alongside downregulation of AKT and p38 MAPK signalling pathways. Placentas from mothers adhering to the Mediterranean diet also showed lower expression of amino acid and glucose transporters SLC3A2 and SLC2A1, as well as altered inflammatory and extracellular matrix remodelling markers, including decreased SOCS3 and GHR and increased PAI1 and MMP3. ConclusionsMaternal adherence to a Mediterranean diet during pregnancy modifies placental lipid composition and regulates pathways involved in lipid handling, nutrient transport, inflammation, and tissue remodelling, providing insight into mechanisms linking maternal diet with placental metabolic function.

physiology↗

Maternal gut Bifidobacterium breve modifies fetal brain metabolism in mice

In recent years, our understanding of the gut microbiomes impact on host physiology and metabolism has grown exponentially. Yet, the specific role of certain microorganisms in regulating gestational health and fetal development remains largely unexplored. During pregnancy, Bifidobacterium represents a key beneficial microbiota genus that provides multiple benefits, including changes in placental development and fetal glycaemia. In this study, using germ-free mice colonized with or without Bifidobacterium breve UCC2003 during pregnancy, we demonstrated that this bacterium is important for controlling fetal brain metabolism. In particular, presence of maternal Bifidobacterium led to reduced levels of ten metabolites (including citrate, 3-hydroxyisobutyrate, and carnitine) in the fetal brain, with concurrent elevated abundance of transporters involved in glucose and branched-chain amino acid uptake. B. breve supplementation was also associated with increased expression of critical metabolic and cellular pathways, including the PI3K-AKT, AMPK, STAT5 and Wnt-{beta}-catenin (including its receptor Frizzled-7) in the fetal brain. Furthermore, maternal-associated Bifidobacterium resulted in HIF-2 protein stabilization and altered a number of https://pubmed.ncbi.nlm.nih.gov/38269505/ genes and proteins involved in cellular growth, axogenesis, and mitochondrial function. These findings highlight that Bifidobacterium breve colonisation of the maternal gut is important for the metabolism and growth of the fetal brain.

developmental biology↗

Fetal manipulation of maternal metabolism is a critical function of Igf2 imprinting

Maternal-offspring interactions in mammals are mainly characterised by cooperation, but also conflict. Over evolutionary time, the fetus has evolved to manipulate the mothers physiology to increase nutrient transfer through the placenta, but these mechanisms are poorly characterized. The imprinted Igf2 (insulin-like growth factor 2) gene is highly expressed in mouse placental cells with endocrine functions. Here, we show that in the mouse, deletion of Igf2 in these cells leads to impaired placental endocrine signalling to the mother, but remarkably does not result in changes in placental morphology, growth or size. Mechanistically, we find that Igf2 via defective production of hormones, including prolactins, is essential for the establishment of the insulin-resistance state during pregnancy, and the appropriate partitioning of nutrients to the developing fetus. Consequently, fetuses are growth restricted and hypoglycemic, due to impaired placental glucose transfer from the mother to the fetus. Furthermore, Igf2 loss from placental endocrine cells has long-lasting effects on offspring adiposity and glucose homeostasis in adult life. Our study provides long-sought compelling experimental evidence for an intrinsic fetal manipulation system, which operates in the placenta to modify maternal metabolism and resource allocation to the fetus, with consequences for offspring metabolic health in later life.

developmental biology↗

Maternal and intrauterine influences on feto-placental growth are accompanied by sexually dimorphic changes in placental mitochondrial respiration, and metabolic signalling pathways

Adverse maternal environments such as small size, malnutrition and metabolic conditions are known to influence fetal growth outcomes. Similarly, fetal growth and metabolic alterations may alter the intrauterine environment and affect all fetuses in multiple gestations/litter bearing species. The placenta is the site of convergence between signals derived from the mother and the developing fetus/es. Its functions are fuelled by energy generated by mitochondrial oxidative phosphorylation (OXPHOS). The aim of this study was to delineate the role of an altered maternal and/or fetal/intrauterine environment in feto-placental growth and placental mitochondrial energetic capacity. To address this, in mice we used disruptions of the gene encoding phosphoinositol 3-kinase (PI3K) p110, a growth and metabolic regulator to perturb the maternal and/or fetal/intrauterine environment and study the impact on wildtype conceptuses. We found that feto-placental growth was modified by a perturbed maternal and intrauterine environment, and effects were most evident for wildtype males compared to females. However, placental mitochondrial complex I+II OXPHOS and total electron transport system (ETS) capacity were similarly reduced for both fetal sexes, yet reserve capacity was additionally decreased in males in response to the maternal and intrauterine perturbations. These were also sex-dependant differences in the placental abundance of mitochondrial-related proteins (e.g. citrate synthase, ETS complexes), and activity of growth/metabolic signalling pathways (AKT and MAPK) with maternal and intrauterine alterations. Our findings thus identify that the mother and intrauterine environment provided by littermates, modulate feto-placental growth, and placental bioenergetics and metabolic signalling in a manner dependent on fetal sex. This may have relevance for understanding the pathways leading to reduced fetal growth, particularly in the context of suboptimal maternal environments and multiple gestations/litter bearing species.

developmental biology↗

Placental mitochondrial function, nutrient transporters, metabolic signalling and steroid metabolism relate to fetal size and sex in mice

Fetal growth depends on placental function, which requires energy from mitochondria. Here we investigated whether mitochondrial function in the placenta relates to growth of the lightest and heaviest fetuses of each sex within the litter of mice. Placentas from the lightest and heaviest fetuses were taken to evaluate placenta morphology (stereology), mitochondrial energetics (high-resolution respirometry), and mitochondrial regulators, nutrient transporters, hormone handling and signalling pathways (qPCR and western blotting). We found that mitochondrial complex I and II oxygen consumption rate was greater for placentas supporting the lightest female fetuses, although placental complex I abundance of the lightest females and complexes III and V of the lightest males were decreased compared to their heaviest counterparts. Expression of mitochondrial biogenesis (Nrf1) and fission (Drp1 and Fis1) genes was lower in the placenta from the lightest females, whilst biogenesis-related gene Tfam was greater in the placenta of the lightest male fetuses. Additionally, placental morphology and steroidogenic gene (Cyp17a1 and Cyp11a1) expression was aberrant for the lightest females, but glucose transporter (Glut1) expression was lower in only the lightest males versus their heaviest counterparts. Differences in intra-litter placental phenotype were related to sex-dependent changes in the expression of hormone responsive (androgen receptor) and metabolic signalling (AMPK, AKT, PPAR{gamma}) pathways. Thus, in normal mouse pregnancy, placental structure, function and mitochondrial phenotype are differentially responsive to growth of the female and the male fetus. This study may inform the design of sex- specific therapies for placental insufficiency and fetal growth abnormalities with life-long benefits for the offspring.

developmental biology↗

Maternal microbiota Bifidobacterium promotes placental vascularization, nutrient transport and fetal growth in mice

The gut microbiota plays a central role in regulating host metabolism. While substantial progress has been made in discerning how the microbiota influences host functions post birth and beyond, little is known about how key members of the maternal gut microbiota can influence feto-placental growth. Notably, in pregnant women, Bifidobacterium represents a key beneficial microbiota genus, with levels observed to increase across pregnancy. Here, using germ-free and specific-pathogen-free mice, we demonstrate that the bacterium Bifidobacterium breve UCC2003 modulates maternal body adaptations, placental structure and nutrient transporter capacity, with implications for fetal metabolism and growth. Maternal and placental metabolome were affected by maternal gut microbiota (i.e. acetate, formate and carnitine). Histological analysis of the placenta confirmed that Bifidobacterium modifies placental structure via changes in Igf2P0, Dlk1, Mapk1 and Mapk14 expression. Additionally, B. breve UCC2003, acting through Slc2a1 and Fatp1-4 transporters, was shown to restore fetal glycaemia and fetal growth in association with changes in the fetal hepatic transcriptome. Our work emphasizes the importance of the maternal gut microbiota on feto-placental development and sets a foundation for future research towards the use of probiotics during pregnancy.

physiology↗

Fetus-derived IGF2 matches placental development to fetal demand

In all eutherian mammals, growth of the fetus is dependent upon a functional placenta, but whether and how the latter adapts to putative fetal signals is currently unknown. Here we demonstrate, through fetal, endothelial, hematopoietic and trophoblast-specific genetic manipulations in the mouse, that endothelial and fetus-derived IGF2 is required for the continuous expansion of the feto-placental microvasculature in late pregnancy. The effects of IGF2 on placental microvasculature expansion are mediated, in part, through IGF2R and angiopoietin-Tie2/TEK signalling. Additionally, IGF2 exerts IGF2R-ERK1/2-dependent pro-proliferative and angiogenic effects on primary feto-placental endothelial cells ex vivo. Endothelial and fetus-derived IGF2 also plays an important role in trophoblast morphogenesis, acting through Gcm1 and Synb. Thus, our study reveals a direct role for the imprinted Igf2-Igf2r axis on matching placental development to fetal growth and establishes the principle that hormone-like signals from the fetus play important roles in controlling placental microvasculature and trophoblast morphogenesis.

developmental biology↗

Fetal and trophoblast PI3Kp110α have distinct roles in regulating resource supply to the growing fetus

Previous studies suggest that the placental supply of nutrients to the fetus adapts according to fetal demand. However, the signaling events underlying placental adaptations remain largely unknown. Earlier work in mice has revealed that loss of the phosphoinositide 3-kinase p110 impairs feto-placental growth but placental nutrient supply is adaptively increased. Here we explore the role of p110 in the epiblast-derived (fetal) and trophoblast lineages of the conceptus in relation to feto-placental growth and placental development and transfer function. Using conditional gene manipulations to knock-down p110 either by [~]50% or [~]100% in the fetal lineages and/or trophoblast, this study shows that p110 in the fetus is essential for prenatal development and a major regulator of placental phenotype in mice. Complete loss of fetal p110 caused embryonic death, whilst heterozygous loss resulted in fetal growth restriction and impaired placental formation and nutrient transport. Loss of trophoblast p110 also resulted in abnormal placental development, although fetuses were viable. However, in response to complete loss of trophoblast p110, the placenta failed to transport sufficient amino acid to match fetal demands for growth. Using RNA-seq, we identified several genes downstream of p110 in the trophoblast that are important in adapting placental phenotype to support fetal growth. Further work using CRISPR/Cas9 genome targeting showed that loss of p110 differentially affects the expression of genes in trophoblast and embryonic stem cells. Our findings thus reveal important, but distinct roles for p110 signaling in the different compartments of the conceptus, which control fetal resource acquisition and ultimately affect healthy growth.\n\nOne Sentence SummaryFetal and trophoblast p110 modify resource allocation

developmental biology↗