Maternal obesity induces epigenetic modifications to facilitate Zfp423 expression and enhance adipogenic differentiation in fetal mice

Lipidomics of infant mesenchymal stem cells associate with the maternal milieu and child adiposity

Our objective was to interrogate mesenchymal stem cell (MSC) lipid metabolism and gestational exposures beyond maternal body mass that may contribute to child obesity risk. MSCs were cultured from term infants of mothers with obesity (n = 16) or normal weight (n = 15). In MSCs undergoing myogenesis in vitro, we used lipidomics to distinguish phenotypes by unbiased cluster analysis and lipid challenge (24-hour excess fatty acid [24hFA]). We measured MSC AMP-activated protein kinase (AMPK) activity and fatty acid oxidation (FAO), and a composite index of maternal glucose, insulin, triglycerides, free fatty acids, TNF-α, and high-density lipoprotein and total cholesterol in fasting blood from mid and late gestation (~17 and ~27 weeks, respectively). We measured child adiposity at birth (n = 29), 4-6 months (n = 29), and 4-6 years (n = 13). Three MSC clusters were distinguished by triacylglycerol (TAG) stores, with greatest TAGs in Cluster 2. All clusters increased acylcarnitines and TAGs with 24hFA, although Cluster 2 was more pronounced and corresponded to AMPK activation and FAO. Maternal metabolic markers predicted MSC clusters and child adiposity at 4-6 years (both highest in Cluster 3). Our data support the notion that MSC phenotypes are predicted by comprehensive maternal metabolic milieu exposures, independent of maternal BMI, and suggest utility as an at-birth predictor for child adiposity, although validation with larger longitudinal samples is warranted.

Nutrigenetic and Epigenetic Mechanisms of Maternal Nutrition-Induced Glucolipid Metabolism Changes in the Offspring

Maternal nutrition during pregnancy regulates the offspring's metabolic homeostasis, including insulin sensitivity and the metabolism of glucose and lipids. The fetus undergoes a crucial period of plasticity in the uterus; metabolic changes in the fetus during pregnancy caused by maternal nutrition not only influence fetal growth and development but also have a long-term or even life-long impact for the offspring. Epigenetic modifications, such as DNA methylation, histone modification, and non-coding RNAs, play important roles in intergenerational and transgenerational effects. In this context, this narrative review comprehensively summarizes and analyzes the molecular mechanisms underlying how maternal nutrition, including a high-fat diet, polyunsaturated fatty acid diet, methyl donor nutrient supplementation, feed restriction, and protein restriction during pregnancy, impacts the genes involved in glucolipid metabolism in the liver, adipose tissue, hypothalamus, muscle, and oocytes of the offspring in terms of the epigenetic modifications. This will provide a foundation for the further exploration of nutrigenetic and epigenetic mechanisms for integrative mother-child nutrition and promotion of the offspring's health through the regulation of maternal nutrition during pregnancy. Note: This paper is part of the Nutrition Reviews Special Collection on Precision Nutrition.

Exploring Maternal Diet-Epigenetic-Gut Microbiome Crosstalk as an Intervention Strategy to Counter Early Obesity Programming

Alterations in a mother's metabolism and endocrine system, due to unbalanced nutrition, may increase the risk of both metabolic and non-metabolic disorders in the offspring's childhood and adulthood. The risk of obesity in the offspring can be determined by the interplay between maternal nutrition and lifestyle, intrauterine environment, epigenetic modifications, and early postnatal factors. Several studies have indicated that the fetal bowel begins to colonize before birth and that, during birth and nursing, the gut microbiota continues to change. The mother's gut microbiota is primarily transferred to the fetus through maternal nutrition and the environment. In this way, it is able to impact the establishment of the early fetal and neonatal microbiome, resulting in epigenetic signatures that can possibly predispose the offspring to the development of obesity in later life. However, antioxidants and exercise in the mother have been shown to improve the offspring's metabolism, with improvements in leptin, triglycerides, adiponectin, and insulin resistance, as well as in the fetal birth weight through epigenetic mechanisms. Therefore, in this extensive literature review, we aimed to investigate the relationship between maternal diet, epigenetics, and gut microbiota in order to expand on current knowledge and identify novel potential preventative strategies for lowering the risk of obesity in children and adults.

Neurodevelopmental Programming of Adiposity: Contributions to Obesity Risk

This review analyzes the published evidence regarding maternal factors that influence the developmental programming of long-term adiposity in humans and animals via the central nervous system (CNS). We describe the physiological outcomes of perinatal underfeeding and overfeeding and explore potential mechanisms that may mediate the impact of such exposures on the development of feeding circuits within the CNS-including the influences of metabolic hormones and epigenetic changes. The perinatal environment, reflective of maternal nutritional status, contributes to the programming of offspring adiposity. The in utero and early postnatal periods represent critically sensitive developmental windows during which the hormonal and metabolic milieu affects the maturation of the hypothalamus. Maternal hyperglycemia is associated with increased transfer of glucose to the fetus driving fetal hyperinsulinemia. Elevated fetal insulin causes increased adiposity and consequently higher fetal circulating leptin concentration. Mechanistic studies in animal models indicate important roles of leptin and insulin in central and peripheral programming of adiposity, and suggest that optimal concentrations of these hormones are critical during early life. Additionally, the environmental milieu during development may be conveyed to progeny through epigenetic marks and these can potentially be vertically transmitted to subsequent generations. Thus, nutritional and metabolic/endocrine signals during perinatal development can have lifelong (and possibly multigenerational) impacts on offspring body weight regulation.

An Updated Review on the Significance of DNA and Protein Methyltransferases and De-methylases in Human Diseases: From Molecular Mechanism to Novel Therapeutic Approaches

Epigenetic mechanisms are crucial in regulating gene expression. These mechanisms include DNA methylation and histone modifications, like methylation, acetylation, and phosphorylation. DNA methylation is associated with gene expression suppression; however, histone methylation can stimulate or repress gene expression depending on the methylation pattern of lysine or arginine residues on histones. These modifications are key factors in mediating the environmental effect on gene expression regulation. Therefore, their aberrant activity is associated with the development of various diseases. The current study aimed to review the significance of DNA and histone methyltransferases and demethylases in developing various conditions, like cardiovascular diseases, myopathies, diabetes, obesity, osteoporosis, cancer, aging, and central nervous system conditions. A better understanding of the epigenetic roles in developing diseases can pave the way for developing novel therapeutic approaches for affected patients.

The Impact of Maternal Obesity on Adipose Progenitor Cells

The concept of Developmental Origin of Health and Disease (DOHaD) postulates that adult-onset metabolic disorders may originate from suboptimal conditions during critical embryonic and fetal programming windows. In particular, nutritional disturbance during key developmental stages may program the set point of adiposity and its associated metabolic diseases later in life. Numerous studies in mammals have reported that maternal obesity and the resulting accelerated growth in neonates may affect adipocyte development, resulting in persistent alterations in adipose tissue plasticity (i.e., adipocyte proliferation and storage) and adipocyte function (i.e., insulin resistance, impaired adipokine secretion, reduced thermogenesis, and higher inflammation) in a sex- and depot-specific manner. Over recent years, adipose progenitor cells (APCs) have been shown to play a crucial role in adipose tissue plasticity, essential for its development, maintenance, and expansion. In this review, we aim to provide insights into the developmental timeline of lineage commitment and differentiation of APCs and their role in predisposing individuals to obesity and metabolic diseases. We present data supporting the possible implication of dysregulated APCs and aberrant perinatal adipogenesis through epigenetic mechanisms as a primary mechanism responsible for long-lasting adipose tissue dysfunction in offspring born to obese mothers.

The Uterine Environment and Childhood Obesity Risk: Mechanisms and Predictions

PURPOSE OF REVIEW

Childhood obesity is a growing health problem in many populations, hence the urgent need to unravel the underlying mechanisms. Some evidence suggests that exposure to suboptimal intrauterine environments can program foetal metabolic health, with adverse consequences in later life, including susceptibility to childhood obesity.

FINDINGS

Factors such as high and low foetal birth weight, excessive gestational-weight-gain, maternal stress and smoking are all associated with increased risk of childhood obesity in observational studies. Animal models, where both genetic background and the postnatal environment can be carefully controlled, suggest that several different mechanisms, including epigenetic changes, dysregulation of adipose tissue development and programming of appetite, may be key drivers of developmental programming of childhood obesity. However, the influence of genetics and the post-natal environment are much more difficult to disentangle as independent effects in human studies, which are also complicated by low follow-up rates. Suboptimal intrauterine environments interact with maternal and foetal genetics and with the postnatal environment to contribute to the risk of childhood obesity. Maternal metabolic challenges, for example obesity and insulin resistance, contribute to the risk of foetal overgrowth and subsequent adiposity in childhood. To protect the long-term health of populations, research focusing on effective means of identifying and intervening in the transgenerational cycle of childhood obesity is required.

Adipocyte hypertrophy in mesenchymal stem cells from infants of mothers with obesity

OBJECTIVE

Fat content of adipocytes derived from infant umbilical cord mesenchymal stem cells (MSCs) predicts adiposity in children through 4 to 6 years of age. This study tested the hypothesis that MSCs from infants born to mothers with obesity (Ob-MSCs) exhibit adipocyte hypertrophy and perturbations in genes regulating adipogenesis compared with MSCs from infants of mothers with normal weight (NW-MSCs).

METHODS

Adipogenesis was induced in MSCs embedded in three-dimensional hydrogel structures, and cell size and number were measured by three-dimensional imaging. Proliferation and protein markers of proliferation and adipogenesis in undifferentiated and adipocyte differentiating cells were measured. RNA sequencing was performed to determine pathways linked to adipogenesis phenotype.

RESULTS

In undifferentiated MSCs, greater zinc finger protein (Zfp)423 protein content was observed in Ob- versus NW-MSCs. Adipocytes from Ob-MSCs were larger but fewer than adipocytes from NW-MSCs. RNA sequencing analysis showed that Zfp423 protein correlated with mRNA expression of genes enriched for cell cycle, MSC lineage specification, inflammation, and metabolism pathways. MSC proliferation was not different before differentiation but declined faster in Ob-MSCs upon adipogenic induction.

CONCLUSIONS

Ob-MSCs have an intrinsic propensity for adipocyte hypertrophy and reduced hyperplasia during adipogenesis in vitro, perhaps linked to greater Zfp423 content and changes in cell cycle pathway gene expression.

Maternal DNA methylation signatures of arsenic exposure is associated with adult offspring insulin resistance in the Strong Heart Study

Exposure to low to moderate arsenic (As) levels has been associated with type 2 diabetes (T2D) and other chronic diseases in American Indian communities. Prenatal exposure to As may also increase the risk for T2D in adulthood, and maternal As has been associated with adult offspring metabolic health measurements. We hypothesized that T2D-related outcomes in adult offspring born to women exposed to low to moderate As can be evaluated utilizing a maternally-derived molecular biosignature of As exposure. Herein, we evaluated the association of maternal DNA methylation with incident T2D and insulin resistance (Homeostatic model assessment of insulin resistance [HOMA2-IR]) in adult offspring. For DNA methylation, we used 20 differentially methylated cytosine-guanine dinucleotides (CpG) previously associated with the sum of inorganic and methylated As species (ΣAs) in urine in the Strong Heart Study (SHS). Of these 20 CpGs, we found six CpGs nominally associated (p < 0.05) with HOMA2-IR in a fully adjusted model that included clinically relevant covariates and offspring adiposity measurements; a similar model that adjusted instead for maternal adiposity measurements found three CpGs nominally associated with HOMA2-IR, two of which overlapped the offspring adiposity model. After adjusting for multiple comparisons, cg03036214 remained associated with HOMA2-IR (q < 0.10) in the offspring adiposity model. The odds ratio of incident T2D increased with an increase in maternal DNA methylation at one HOMA2-IR associated CpG in the model adjusting for offspring adiposity, cg12116137, whereas adjusting for maternal adiposity had a minimal effect on the association. Our data suggests offspring adiposity, rather than maternal adiposity, potentially influences the effects of maternal DNAm signatures on offspring metabolic health parameters. Here, we have presented evidence supporting a role for epigenetic biosignatures of maternal As exposure as a potential biomarker for evaluating risk of T2D-related outcomes in offspring later in life.

Maternal obesity and programming of metabolic syndrome in the offspring: searching for mechanisms in the adipocyte progenitor pool

BACKGROUND

It is now understood that it is the quality rather than the absolute amount of adipose tissue that confers risk for obesity-associated disease. Adipose-derived stem cells give rise to adipocytes during the developmental establishment of adipose depots. In adult depots, a reservoir of progenitors serves to replace adipocytes that have reached their lifespan and for recruitment to increase lipid buffering capacity under conditions of positive energy balance. MAIN: The adipose tissue expandability hypothesis posits that a failure in de novo differentiation of adipocytes limits lipid storage capacity and leads to spillover of lipids into the circulation, precipitating the onset of obesity-associated disease. Since adipose progenitors are specified to their fate during late fetal life, perturbations in the intrauterine environment may influence the rapid expansion of adipose depots that occurs in childhood or progenitor function in established adult depots. Neonates born to mothers with obesity or diabetes during pregnancy tend to have excessive adiposity at birth and are at increased risk for childhood adiposity and cardiometabolic disease.

CONCLUSION

In this narrative review, we synthesize current knowledge in the fields of obesity and developmental biology together with literature from the field of the developmental origins of health and disease (DOHaD) to put forth the hypothesis that the intrauterine milieu of pregnancies complicated by maternal metabolic disease disturbs adipogenesis in the fetus, thereby accelerating the trajectory of adipose expansion in early postnatal life and predisposing to impaired adipose plasticity.

Fat content in infant mesenchymal stem cells prospectively associates with childhood adiposity and fasting glucose

OBJECTIVE

In human studies, new model systems are needed for improved mechanistic investigation of developmental predisposition for metabolic disease but also to serve as benchmarks in early life prevention or intervention efforts. In this regard, human infant umbilical cord-derived mesenchymal stem cells (MSCs) are an emerging tool. However, long-term clinical relevance to in vivo markers of metabolic disease is unknown.

METHODS

In a cohort of 124 mother/child dyads, this study tested the hypothesis that triglyceride content (TG) of infant MSCs undergoing adipogenesis in vitro (MSC-TG) is associated with in vivo adiposity (percent fat mass) from birth to early childhood and with fasting glucose and insulin in early childhood.

RESULTS

MSC-TG was positively associated with in vivo child adiposity at birth, age 4 to 6 months, and age 4 to 6 years. MSC-TG was associated with fasting glucose, but not insulin, at 4 to 6 years. Importantly, MSC-TG explained an additional 13% variance in child adiposity at 4 to 6 years, after accounting for other established birth predictors (weight and percent fat mass at birth) and other established covariates related to child adiposity (e.g., breastfeeding exposure, physical activity).

CONCLUSIONS

This work demonstrates the strength of the MSC model for predicting offspring metabolic phenotype into childhood, even when considering the important contribution of other early life risk factors.

Maternal exercise improves epithelial development of fetal intestine by enhancing apelin signaling and oxidative metabolism

Obesity in pregnancy is currently the leading cause of gestational complications for the mother and fetus worldwide. Maternal obesity (MO), common in western societies, impedes development of intestinal epithelium in the fetuses, which causes disorders in the nutrient absorption and intestine-related immune responses in offspring. Here, using a mouse model of maternal exercise (ME), we found that exercise during pregnancy protects the impairment of fetal intestinal morphometrical formation and epithelial development due to MO. MO decreased villus length and epithelial proliferation markers in E18.5 fetal small intestine, which was increased due to ME. The expression of the epithelial differentiation markers, Lyz1, Muc2, and Tff3, in fetal small intestine was decreased due to MO, but protected by ME. Consistently, the biomarkers related to mitochondrial biogenesis and oxidative metabolism were downregulated in MO fetal small intestine but recovered by ME. Apelin injection to dams partially mirrored the beneficial effects of ME. ME and apelin injection activated AMPK, the downstream target of apelin receptor signaling, which might mediate the improvement of fetal epithelial development and oxidative metabolism. These findings suggest that ME, a highly accessible intervention, is effective in improving fetal intestinal epithelium of obese dams. Apelin-AMPK-mitochondrial biogenesis axis provides amenable therapeutic targets to facilitate fetal intestinal development of obese mothers.

Acquired lymphedema: Molecular contributors and future directions for developing intervention strategies

Lymphedema is a debilitating chronic disease that mostly develops as an adverse reaction to cancer treatment modalities such as chemotherapy, surgery, and radiotherapy. Lymphedema also appears to be a deteriorating consequence of roundworm infections, as best represented by filariasis. According to its origin, lymphedema is classified as primary lymphedema and acquired lymphedema. The latter is an acquired condition that, hitherto, received a considerably low attention owing to the less number of fatal cases been reported. Notably, despite the low mortality rate in lymphedema, it has been widely reported to reduce the disease-free survival and thus the quality of life of affected patients. Hence, in this review, we focused on acquired lymphedema and orchestration of molecular interplays associated with either stimulation or inhibition of lymphedema development that were, in vast majority, clearly depicted in animal models with their specific and distinct technical approaches. We also discussed some recent progress made in phytochemical-based anti-lymphedema intervention strategies and the specific mechanisms underlying their anti-lymphedema properties. This review is crucial to understand not only the comprehensive aspects of the disease but also the future directions of the intervention strategies that can address the quality of life of affected patients rather than alleviating apparent symptoms only.

Parental obesity-induced changes in developmental programming

Many studies support the link between parental obesity and the predisposition to develop adult-onset metabolic syndromes that include obesity, high blood pressure, dyslipidemia, insulin resistance, and diabetes in the offspring. As the prevalence of obesity increases in persons of childbearing age, so does metabolic syndrome in their descendants. Understanding how parental obesity alters metabolic programs in the progeny, predisposing them to adult-onset metabolic syndrome, is key to breaking this cycle. This review explores the basis for altered metabolism of offspring exposed to overnutrition by focusing on critical developmental processes influenced by parental obesity. We draw from human and animal model studies, highlighting the adaptations in metabolism that occur during normal pregnancy that become maladaptive with obesity. We describe essential phases of development impacted by parental obesity that contribute to long-term alterations in metabolism in the offspring. These encompass gamete formation, placentation, adipogenesis, pancreas development, and development of brain appetite control circuits. Parental obesity alters the developmental programming of these organs in part by inducing epigenetic changes with long-term consequences on metabolism. While exposure to parental obesity during any of these phases is sufficient to alter long-term metabolism, offspring often experience multiple exposures throughout their development. These insults accumulate to increase further the susceptibility of the offspring to the obesogenic environments of modern society.

Nutrigenomics in livestock sector and its human-animal interface-a review

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Nutrigenomics unfolds the link between nutrition and gene expression for productivity.expression profile of intramuscular.

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Nutrigenomics helps scientists discover genes and DNA in each animal's cell or tissue by assisting them in selecting nutrients.

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It brings out the importance of micronutrition for increasing animal production.

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Nutrigenomics integrates nutrition, molecular biology, genomics, bioinformatics, molecular medicine, and epidemiology.

Noncommunicable diseases such as cardiovascular disease, obesity, diabetes, and cancer now outnumber all other health ailments in humans globally due to abrupt changes in lifestyle following the industrial revolution. The industrial revolution has also intensified livestock farming, resulting in an increased demand for productivity and stressed animals. The livestock industry faces significant challenges from a projected sharp increase in global food and high animal protein demand. Nutrition genomics holds great promise for the future as its advances have opened up a whole new world of disease understanding and prevention. Nutrigenomics is the study of the interactions between genes and diet. It investigates molecular relationships between nutrients and genes to identify how even minor modifications could potentially alter animal and human health/performance by using techniques like proteomics, transcriptomics, metabolomics, and lipidomics. Dietary modifications mostly studied in livestock focus mainly on health and production traits through protein, fat, mineral, and vitamin supplementation changes. Nutrigenomics meticulously selects nutrients for fine-tuning the expression of genes that match animal/human genotypes for better health, productivity, and the environment. As a step forward, nutrigenomics integrates nutrition, molecular biology, genomics, bioinformatics, molecular medicine, and epidemiology to better understand the role of food as an epigenetic factor in the occurrence of these diseases. This review aims to provide a comprehensive overview of the fundamental concepts, latest advances, and studies in the field of nutrigenomics, emphasizing the interaction of diet with gene expression, and how it relates to human and animal health along with its human-animal interphase.

Multi-Level Analysis of Adipose Tissue Reveals the Relevance of Perivascular Subpopulations and an Increased Endothelial Permeability in Early-Stage Lipedema

Lipedema is a chronic, progressive disease of adipose tissue with unknown etiology. Based on the relevance of the stromal vascular fraction (SVF) cell population in lipedema, we performed a thorough characterization of subcutaneous adipose tissue, SVF isolated thereof and the sorted populations of endothelial cells (EC), pericytes and cultured adipose-derived stromal/stem cells (ASC) of early-stage lipedema patients. We employed histological and gene expression analysis and investigated the endothelial barrier by immunofluorescence and analysis of endothelial permeability in vitro. Although there were no significant differences in histological stainings, we found altered gene expression of factors relevant for local estrogen metabolism (aromatase), preadipocyte commitment (ZNF423) and immune cell infiltration (CD11c) in lipedema on the tissue level, as well as in distinct cellular subpopulations. Machine learning analysis of immunofluorescence images of CD31 and ZO-1 revealed a morphological difference in the cellular junctions of EC cultures derived from healthy and lipedema individuals. Furthermore, the secretome of lipedema-derived SVF cells was sufficient to significantly increase leakiness of healthy human primary EC, which was also reflected by decreased mRNA expression of VE-cadherin. Here, we showed for the first time that the secretome of SVF cells creates an environment that triggers endothelial barrier dysfunction in early-stage lipedema. Moreover, since alterations in gene expression were detected on the cellular and/or tissue level, the choice of sample material is of high importance in elucidating this complex disease.

The Potential of Prebiotic and Probiotic Supplementation During Obese Pregnancy to Improve Maternal and Offspring’s Metabolic Health and Reduce Obesity Risk—A Narrative Review

Worldwide, obesity prevalence is rising, severely impairing the health of those affected by increasing their risk for developing non-communicable diseases. The pathophysiology of obesity is complex and caused by a variety of genetic and environmental factors. Recent findings suggest that obesity is partly caused by dysbiosis, an imbalanced gut microbiome. In the context of pregnancy, maternal dysbiosis increases the child’s obesity risk, causing an intergenerational cycle of obesity. Accordingly, interventions modulating the gut microbiome have the potential to interrupt this cycle. This review discusses the potential of pre- and probiotic interventions in modulating maternal obesity associated dysbiosis to limit the child’s obesity risk. The literature search resulted in four animal studies using prebiotics as well as one animal study and six human studies using probiotics. Altogether, prebiotic supplementation in animals successfully decreased the offspring’s obesity risk, while probiotic supplementation in humans failed to show positive impacts in the offspring. However, comparability between studies is limited and considering the complexity of the topic, more studies in this field are required.

Maternal Obesity Programming of Perivascular Adipose Tissue and Associated Immune Cells: An Understudied Area With Few Answers and Many Questions

At present, the worldwide prevalence of obesity has become alarmingly high with estimates foreshadowing a continued escalation in the future. Furthermore, there is growing evidence attributing an individual’s predisposition for developing obesity to maternal health during gestation. Currently, 60% of pregnancies in the US are to either overweight or obese mothers which in turn contributes to the persistent rise in obesity rates. While obesity itself is problematic, it conveys an increased risk for several diseases such as diabetes, inflammatory disorders, cancer and cardiovascular disease (CVD). Additionally, as we are learning more about the mechanisms underlying CVD, much attention has been brought to the role of perivascular adipose tissue (PVAT) in maintaining cardiovascular health. PVAT regulates vascular tone and for a significant number of individuals, obesity elicits PVAT disruption and dysregulation of vascular function. Obesity elicits changes in adipocyte and leukocyte populations within PVAT leading to an inflammatory state which promotes vasoconstriction thereby aiding the onset/progression of CVD. Our current understanding of obesity, PVAT and CVD has only been examined at the individual level without consideration for a maternal programming effect. It is unknown if maternal obesity affects the propensity for PVAT remodeling in the offspring, thereby enhancing the obesity/CVD link, and what role PVAT leukocytes play in this process. This perspective will focus on the maternal contribution of the interplay between obesity, PVAT disruption and CVD and will highlight the leukocyte/PVAT interaction as a novel target to stem the tide of the current obesity epidemic and its secondary health consequences.

Accelerated developmental adipogenesis programs adipose tissue dysfunction and cardiometabolic risk in offspring born to dams with metabolic dysfunction

This study determined if a perturbation in in utero adipogenesis leading to later life adipose tissue (AT) dysfunction underlies programming of cardiometabolic risk in offspring born to dams with metabolic dysfunction. Female mice heterozygous for the leptin receptor deficiency (Het_db) had 2.4-fold higher prepregnancy fat mass and in late gestation had higher plasma insulin and triglycerides compared with wild-type (Wt) females (P < 0.05). To isolate the role of the intrauterine milieu, wild-type (Wt) offspring from each pregnancy were studied. Differentiation potential in isolated progenitors and cell size distribution analysis revealed accelerated adipogenesis in Wt pups born to Het_db dams, accompanied by a higher accumulation of neonatal fat mass. In adulthood, whole body fat mass by NMR was higher in male (69%) and female (20%) Wt offspring born to Het_db versus Wt pregnancies, along with adipocyte hypertrophy and hyperlipidemia (all P < 0.05). Lipidomic analyses by gas chromatography revealed an increased lipogenic index (16:0/18:2n6) after high-fat/fructose diet (HFFD). Postprandial insulin, ADIPO-IR, and ex vivo AT lipolytic responses to isoproterenol were all higher in Wt offspring born to Het_db dams (P < 0.05). Intrauterine metabolic stimuli may direct a greater proportion of progenitors toward terminal differentiation, thereby predisposing to hypertrophy-induced adipocyte dysfunction.NEW & NOTEWORTHY This study reveals that accelerated adipogenesis during the perinatal window of adipose tissue development predisposes to later life hypertrophic adipocyte dysfunction, thereby compromising the buffering function of the subcutaneous depot.

Aberrant DNA Methylation Mediates the Transgenerational Risk of Metabolic and Chronic Disease Due to Maternal Obesity and Overnutrition

Maternal obesity is a rapidly evolving universal epidemic leading to acute and long-term medical and obstetric health issues, including increased maternal risks of gestational diabetes, hypertension and pre-eclampsia, and the future risks for offspring's predisposition to metabolic diseases. Epigenetic modification, in particular DNA methylation, represents a mechanism whereby environmental effects impact on the phenotypic expression of human disease. Maternal obesity or overnutrition contributes to the alterations in DNA methylation during early life which, through fetal programming, can predispose the offspring to many metabolic and chronic diseases, such as non-alcoholic fatty liver disease, obesity, diabetes, and chronic kidney disease. This review aims to summarize findings from human and animal studies, which support the role of maternal obesity in fetal programing and the potential benefit of altering DNA methylation to limit maternal obesity related disease in the offspring.

Metabolic Disease Programming: From Mitochondria to Epigenetics, Glucocorticoid Signalling and Beyond

Embryonic and foetal development are critical periods of development in which several environmental cues determine health and disease in adulthood. Maternal conditions and an unfavourable intrauterine environment impact foetal development and may programme the offspring for increased predisposition to metabolic diseases and other chronic pathologic conditions throughout adult life. Previously, non-communicable chronic diseases were only associated with genetics and lifestyle. Now the origins of non-communicable chronic diseases are associated with early-life adaptations that produce long-term dysfunction. Early-life environment sets the long-term health and disease risk and can span through multiple generations. Recent research in developmental programming aims at identifying the molecular mechanisms responsible for developmental programming outcomes that impact cellular physiology and trigger adulthood disease. The identification of new therapeutic targets can improve offspring's health management and prevent or overcome adverse consequences of foetal programming. This review summarizes recent biomedical discoveries in the Developmental Origins of Health and Disease (DOHaD) hypothesis and highlight possible developmental programming mechanisms, including prenatal structural defects, metabolic (mitochondrial dysfunction, oxidative stress, protein modification), epigenetic and glucocorticoid signalling-related mechanisms suggesting molecular clues for the causes and consequences of programming of increased susceptibility of offspring to metabolic disease after birth. Identifying mechanisms involved in DOHaD can contribute to early interventions in pregnancy or early childhood, to re-set the metabolic homeostasis and break the chain of subsequent events that could lead to the development of disease.

Effect of Polyphenols Intake on Obesity-Induced Maternal Programming

Excess caloric intake and body fat accumulation lead to obesity, a complex chronic disease that represents a significant public health problem due to the health-related risk factors. There is growing evidence showing that maternal obesity can program the offspring, which influences neonatal phenotype and predispose offspring to metabolic disorders such as obesity. This increased risk may also be epigenetically transmitted across generations. Thus, there is an imperative need to find effective reprogramming approaches in order to resume normal fetal development. Polyphenols are bioactive compounds found in vegetables and fruits that exert its anti-obesity effect through its powerful anti-oxidant and anti-inflammatory activities. Polyphenol supplementation has been proven to counteract the prejudicial effects of maternal obesity programming on progeny. Indeed, some polyphenols can cross the placenta and protect the fetal predisposition against obesity. The present review summarizes the effects of dietary polyphenols on obesity-induced maternal reprogramming as an offspring anti-obesity approach.

Maternal metabolic health drives mesenchymal stem cell metabolism and infant fat mass at birth

Exposure to maternal obesity may promote metabolic dysfunction in offspring. We used infant mesenchymal stem cells (MSCs) to experimentally examine cellular mechanisms of intergenerational health transmission. Our earlier reports show MSCs collected from infants of mothers with obesity had a dichotomous distribution in metabolic efficiency; they were either efficient (Ef-Ob) or inefficient (In-Ob) with respect to fatty acid oxidation (FAO). Here, we sought to determine if this was due to a primary defect in FAO. Accordingly, we measured FAO in myogenic differentiating MSCs under 3 conditions: (a) myogenesis alone, (b) excess fatty acid exposure, and (c) excess fatty acid exposure plus a chemical uncoupler to increase metabolic rate. Compared with normal weight and Ef-Ob MSCs, In-Ob displayed lower FAO in myogenesis alone and after fatty acid plus uncoupler, indicating In-Ob were less metabolically flexible after increasing lipid availability and metabolic rate, demonstrating a primary deficit in FAO. MSC FAO was negatively associated with fasting maternal glucose and insulin and positively associated with fasting HDL-cholesterol. MSC FAO was negatively associated with infant fat mass. These data indicate a less favorable maternal metabolic milieu, independent of maternal BMI, reduces intrinsic MSC FAO and is linked to higher infant adiposity as early as birth.

Overweight and obesity in pregnancy: their impact on epigenetics

Over the last few decades, the prevalence of obesity has risen to epidemic proportions worldwide. Consequently, the number of obesity in pregnancy has risen drastically. Gestational overweight and obesity are associated with impaired outcomes for mother and child. Furthermore, studies show that maternal obesity can lead to long-term consequences in the offspring, increasing the risk for obesity and cardiometabolic disease in later life. In addition to genetic mechanisms, mounting evidence demonstrates the induction of epigenetic alterations by maternal obesity, which can affect the offspring’s phenotype, thereby influencing the later risk of obesity and cardiometabolic disease. Clear evidence in this regard comes from various animal models of maternal obesity. Evidence derived from clinical studies remains limited. The current article gives an overview of pathophysiological changes associated with maternal obesity and their consequences on placental structure and function. Furthermore, a short excurse is given on epigenetic mechanisms and emerging data regarding a putative interaction between metabolism and epigenetics. Finally, a summary of important findings of animal and clinical studies investigating maternal obesity-related epigenetic effects is presented also addressing current limitations of clinical studies.

Developmental programming of offspring adipose tissue biology and obesity risk

Obesity is reaching epidemic proportions and imposes major negative health crises and an economic burden in both high and low income countries. The multifaceted nature of obesity represents a major health challenge, with obesity affecting a variety of different organs and increases the risk of many other noncommunicable diseases, such as type 2 diabetes, fatty liver disease, dementia, cardiovascular diseases, and even cancer. The defining organ of obesity is the adipose tissue, highlighting the need to more comprehensively understand the development and biology of this tissue to understand the pathogenesis of obesity. Adipose tissue is a miscellaneous and highly plastic endocrine organ. It comes in many different sizes and shades and is distributed throughout many different locations in the body. Though its development begins prenatally, quite uniquely, it has the capacity for unlimited growth throughout adulthood. Adipose tissue is also a highly sexually dimorphic tissue, patterning men and women in different ways, which means the risks associated with obesity are also sexually dimorphic. Recent studies show that environmental factors during prenatal and early stages of postnatal development have the capacity to programme the structure and function of adipose tissue, with implications for the development of obesity. This review summarizes the evidence for a role for early environmental factors, such as maternal malnutrition, hypoxia, and exposure to excess hormones and endocrine disruptors during gestation in the programming of adipose tissue and obesity in the offspring. We will also discuss the complexity of studying adipose tissue biology and the importance of appreciating nuances in adipose tissue, such as sexual dimorphism and divergent responses to metabolic and endocrine stimuli. Given the rising levels of obesity worldwide, understanding how environmental conditions in early life affects adipose tissue phenotype and the subsequent development of obesity is of absolute importance.

Young-Onset Carcinogenesis - The Potential Impact of Perinatal and Early Life Metabolic Influences on the Epigenome

The last decade has witnessed a significant rise in cancers in young adults. This spectrum of solid organ cancers occurring in individuals under the age of 40 years (some reports extending the age-group to <50 years) in whom aetiology of cancer cannot be traced back to pre-existing familial cancer syndromes, is referred to as termed young-, or early- onset cancers. The underlying causes for young-onset carcinogenesis have remained speculative. We recently proposed a hypothesis to explain the causation of this entity. We propose that the risk for young-onset cancer begins in the perinatal period as a result of the exposure of the foetus to stressors, including maternal malnutrition, smoking or alcohol, with the consequent epigenomic events triggered to help the foetus cope/adapt. Exposure to the same stressors, early in the life of that individual, facilitates a re-activation of these 'responses designed to be protective' but ultimately resulting in a loss of regulation at a metabolic and/or genetic level culminating in the evolution of the neoplastic process. In this manuscript, we will provide a rationale for this hypothesis and present evidence to further support it by clarifying the pathways involved, including elucidating a role for Acetyl-CoA and its effect on the epigenome. We present strategies and experimental models that can be used to test the hypothesis. We believe that a concerted effort by experts in different, but complementary fields, such as epidemiology, genetics, and epigenetics united towards the common goal of deciphering the underlying cause for young-onset cancers is the urgent need. Such efforts might serve to prove, or disprove, the presented hypothesis. However, the more important aim is to develop strategies to reverse the disturbing trend of the rise in young-onset cancers.

Maternal obesity as a risk factor for developing diabetes in offspring: An epigenetic point of view

According to the developmental origin of health and disease concept, the risk of many age-related diseases is not only determined by genetic and adult lifestyle factors but also by factors acting during early development. In particular, maternal obesity and neonatal accelerated growth predispose offspring to overweight and type 2 diabetes (T2D) in adulthood. This concept mainly relies on the developmental plasticity of adipose tissue and pancreatic β-cell programming in response to suboptimal milieu during the perinatal period. These changes result in unhealthy hypertrophic adipocytes with decreased capacity to store fat, low-grade inflammation and loss of insulin-producing pancreatic β-cells. Over the past years, many efforts have been made to understand how maternal obesity induces long-lasting adipose tissue and pancreatic β-cell dysfunction in offspring and what are the molecular basis of the transgenerational inheritance of T2D. In particular, rodent studies have shed light on the role of epigenetic mechanisms in linking maternal nutritional manipulations to the risk for T2D in adulthood. In this review, we discuss epigenetic adipocyte and β-cell remodeling during development in the progeny of obese mothers and the persistence of these marks as a basis of obesity and T2D predisposition.

Epigenetic Regulation of Adipogenesis in Development of Metabolic Syndrome

Obesity is one of the biggest public health concerns identified by an increase in adipose tissue mass as a result of adipocyte hypertrophy and hyperplasia. Pertaining to the importance of adipose tissue in various biological processes, any alteration in its function results in impaired metabolic health. In this review, we discuss how adipose tissue maintains the metabolic health through secretion of various adipokines and inflammatory mediators and how its dysfunction leads to the development of severe metabolic disorders and influences cancer progression. Impairment in the adipocyte function occurs due to individuals' genetics and/or environmental factor(s) that largely affect the epigenetic profile leading to altered gene expression and onset of obesity in adults. Moreover, several crucial aspects of adipose biology, including the regulation of different transcription factors, are controlled by epigenetic events. Therefore, understanding the intricacies of adipogenesis is crucial for recognizing its relevance in underlying disease conditions and identifying the therapeutic interventions for obesity and metabolic syndrome.

Maternal Nutrition During Gestation Alters Histochemical Properties, and mRNA and microRNA Expression in Adipose Tissue of Wagyu Fetuses

We hypothesized that maternal low or high nutrition would give unique effects to morphological and molecular dynamics in adipose tissue of fetus of fatty breed Wagyu (Japanese Black) cattle which produce highly marbled beef. This study aimed to determine the effects of maternal energy intake in Wagyu cows, during gestation on fetal adipose tissue development, histochemical properties, and gene and microRNA (miRNA) expression. Cows were allocated to one of two nutritional energy groups: 120% (HIGH) or 60% nutritional requirements of (LOW). Fetuses (n = 6 per treatment) were removed from pregnant cows by cesarean section at fetal age 260 ± 8 days and euthanized. Subcutaneous adipose tissue (SAT), thoracic cavity visceral adipose tissue (TVAT), and perirenal adipose tissue (PAT) were collected for analysis. In histochemical analysis, in SAT and PAT, HIGH fetuses had greater diameter of adipocytes than LOW fetuses (P<0.05). Only in SAT, LOW fetuses had more Leptin (LEP) mRNA and tended to have more Peroxisome Proliferator-Activated Receptor gamma (PPARG) CCAAT-enhancer-binding proteins alpha (CEBPA) and Glucose transporter (GLUT) 4 mRNA(P<0.10). In all SAT, TVAT, and PAT, LOW fetuses had higher levels of the brown adipose tissue (BAT) biomarkers Uncoupling Protein (UCP) 1 and PPARG coactivator (PGC) 1α mRNA than HIGH fetuses (P<0.08). Meanwhile, in the other adipose tissue, LOW fetuses had lower PPARG, CEBPA, and Zinc Finger Protein (ZFP) 423 (in TVAT and PAT), FASN (in TVAT), LEP and GLUT4 mRNA (in PAT; P<0.10). In particular, in TVAT and PAT, LOW fetuses exhibited lower expression of WAT biomarkers (PPARG and ZFP423). Differential expression of various miRNAs related to adipogenesis between the LOW and HIGH fetuses was detected in an adipose tissue-specific manner (P<0.10). Based on adipose tissue-specific effects of maternal nutrition, these findings suggested that poor maternal nutrition in Wagyu cattle increased BAT development in SAT, TVAT and PAT, while elevated maternal nutrition stimulated fetal SAT development compared with that of TVAT and PAT.

Increased prostaglandin-D2 in male STAT3-deficient hearts shifts cardiac progenitor cells from endothelial to white adipocyte differentiation

Cardiac levels of the signal transducer and activator of transcription factor-3 (STAT3) decline with age, and male but not female mice with a cardiomyocyte-specific STAT3 deficiency conditional knockout (CKO) display premature age-related heart failure associated with reduced cardiac capillary density. In the present study, isolated male and female CKO-cardiomyocytes exhibit increased prostaglandin (PG)-generating cyclooxygenase-2 (COX-2) expression. The PG-degrading hydroxyprostaglandin-dehydrogenase-15 (HPGD) expression is only reduced in male cardiomyocytes, which is associated with increased prostaglandin D₂ (PGD₂) secretion from isolated male but not female CKO-cardiomyocytes. Reduced HPGD expression in male cardiomyocytes derive from impaired androgen receptor (AR)–signaling due to loss of its cofactor STAT3. Elevated PGD₂ secretion in males is associated with increased white adipocyte accumulation in aged male but not female hearts. Adipocyte differentiation is enhanced in isolated stem cell antigen-1 (SCA-1)⁺ cardiac progenitor cells (CPC) from young male CKO-mice compared with the adipocyte differentiation of male wild-type (WT)-CPC and CPC isolated from female mice. Epigenetic analysis in freshly isolated male CKO-CPC display hypermethylation in pro-angiogenic genes (Fgfr2, Epas1) and hypomethylation in the white adipocyte differentiation gene Zfp423 associated with up-regulated ZFP423 expression and a shift from endothelial to white adipocyte differentiation compared with WT-CPC. The expression of the histone-methyltransferase EZH2 is reduced in male CKO-CPC compared with male WT-CPC, whereas no differences in the EZH2 expression in female CPC were observed. Clonally expanded CPC can differentiate into endothelial cells or into adipocytes depending on the differentiation conditions. ZFP423 overexpression is sufficient to induce white adipocyte differentiation of clonal CPC. In isolated WT-CPC, PGD₂ stimulation reduces the expression of EZH2, thereby up-regulating ZFP423 expression and promoting white adipocyte differentiation. The treatment of young male CKO mice with the COX inhibitor Ibuprofen or the PGD₂ receptor (DP)2 receptor antagonist BAY-u 3405 in vivo increased EZH2 expression and reduced ZFP423 expression and adipocyte differentiation in CKO-CPC. Thus, cardiomyocyte STAT3 deficiency leads to age-related and sex-specific cardiac remodeling and failure in part due to sex-specific alterations in PGD₂ secretion and subsequent epigenetic impairment of the differentiation potential of CPC. Causally involved is the impaired AR signaling in absence of STAT3, which reduces the expression of the PG-degrading enzyme HPGD.

Impaired androgen-receptor-signaling due to STAT3-deficiency promotes increased prostaglandin-D2-secretion from male but not female cardiomyocytes; this induces an epigenetic switch in cardiac progenitor cells from endothelial to white adipocyte differentiation, associated with reduced cardiac capillary density, increased cardiac white fat deposits and heart failure in aged male but not female mice.

Global DNA methylation pattern involved in the modulation of differentiation potential of adipogenic and myogenic precursors in skeletal muscle of pigs

Background

Skeletal muscle is a complex and heterogeneous tissue accounting for approximately 40% of body weight. Excessive ectopic lipid accumulation in the muscle fascicle would undermine the integrity of skeletal muscle in humans but endow muscle with marbling-related characteristics in farm animals. Therefore, the balance of myogenesis and adipogenesis is of great significance for skeletal muscle homeostasis. Significant DNA methylation occurs during myogenesis and adipogenesis; however, DNA methylation pattern of myogenic and adipogenic precursors derived from skeletal muscle remains unknown yet.

Methods

In this study, reduced representation bisulfite sequencing was performed to analyze genome-wide DNA methylation of adipogenic and myogenic precursors derived from the skeletal muscle of neonatal pigs. Integrated analysis of DNA methylation and transcription profiles was further conducted. Based on the results of pathway enrichment analysis, myogenic precursors were transfected with CACNA2D2-overexpression plasmids to explore the function of CACNA2D2 in myogenic differentiation.

Results

As a result, 11,361 differentially methylated regions mainly located in intergenic region and introns were identified. Furthermore, 153 genes with different DNA methylation and gene expression level between adipogenic and myogenic precursors were characterized. Subsequently, pathway enrichment analysis revealed that DNA methylation programing was involved in the regulation of adipogenic and myogenic differentiation potential through mediating the crosstalk among pathways including focal adhesion, regulation of actin cytoskeleton, MAPK signaling pathway, and calcium signaling pathway. In particular, we characterized a new role of CACNA2D2 in inhibiting myogenic differentiation by suppressing JNK/MAPK signaling pathway.

Conclusions

This study depicted a comprehensive landmark of DNA methylome of skeletal muscle-derived myogenic and adipogenic precursors, highlighted the critical role of CACNA2D2 in regulating myogenic differentiation, and illustrated the possible regulatory ways of DNA methylation on cell fate commitment and skeletal muscle homeostasis.

Supplementary information

The online version contains supplementary material available at 10.1186/s13287-020-02053-3.

Molecular mechanisms governing offspring metabolic programming in rodent models of in utero stress

The results of different human epidemiological datasets provided the impetus to introduce the now commonly accepted theory coined as 'developmental programming', whereby the presence of a stressor during gestation predisposes the growing fetus to develop diseases, such as metabolic dysfunction in later postnatal life. However, in a clinical setting, human lifespan and inaccessibility to tissue for analysis are major limitations to study the molecular mechanisms governing developmental programming. Subsequently, studies using animal models have proved indispensable to the identification of key molecular pathways and epigenetic mechanisms that are dysregulated in metabolic organs of the fetus and adult programmed due to an adverse gestational environment. Rodents such as mice and rats are the most used experimental animals in the study of developmental programming. This review summarises the molecular pathways and epigenetic mechanisms influencing alterations in metabolic tissues of rodent offspring exposed to in utero stress and subsequently programmed for metabolic dysfunction. By comparing molecular mechanisms in a variety of rodent models of in utero stress, we hope to summarise common themes and pathways governing later metabolic dysfunction in the offspring whilst identifying reasons for incongruencies between models so to inform future work. With the continued use and refinement of such models of developmental programming, the scientific community may gain the knowledge required for the targeted treatment of metabolic diseases that have intrauterine origins.

Epigenetic Programming of Adipose Tissue in the Progeny of Obese Dams

According to the Developmental Origin of Health and Disease (DOHaD) concept, maternal obesity and the resulting accelerated growth in neonates predispose offspring to obesity and associated metabolic diseases that may persist across generations. In this context, the adipose tissue has emerged as an important player due to its involvement in metabolic health, and its high potential for plasticity and adaptation to environmental cues. Recent years have seen a growing interest in how maternal obesity induces long-lasting adipose tissue remodeling in offspring and how these modifications could be transmitted to subsequent generations in an inter- or transgenerational manner. In particular, epigenetic mechanisms are thought to be key players in the developmental programming of adipose tissue, which may partially mediate parts of the transgenerational inheritance of obesity. This review presents data supporting the role of maternal obesity in the developmental programming of adipose tissue through epigenetic mechanisms. Inter- and transgenerational effects on adipose tissue expansion are also discussed in this review.

Nonnutritive sweetener consumption during pregnancy, adiposity, and adipocyte differentiation in offspring: evidence from humans, mice, and cells

BACKGROUND

Obesity often originates in early life, and is linked to excess sugar intake. Nonnutritive sweeteners (NNS) are widely consumed as "healthier" alternatives to sugar, yet recent evidence suggests NNS may adversely influence weight gain and metabolic health. The impact of NNS during critical periods of early development has rarely been studied. We investigated the effect of prenatal NNS exposure on postnatal adiposity and adipocyte development.

METHODS

In the CHILD birth cohort (N = 2298), we assessed maternal NNS beverage intake during pregnancy and child body composition at 3 years, controlling for maternal BMI and other potential confounders. To investigate causal mechanisms, we fed NNS to pregnant C57BL6J mice at doses relevant to human consumption (42 mg/kg/day aspartame or 6.3 mg/kg/day sucralose), and assessed offspring until 12 weeks of age for: body weight, adiposity, adipose tissue morphology and gene expression, glucose and insulin tolerance. We also studied the effect of sucralose on lipid accumulation and gene expression in cultured 3T3-L1 pre-adipocyte cells.

RESULTS

In the CHILD cohort, children born to mothers who regularly consumed NNS beverages had elevated body mass index (mean z-score difference +0.23, 95% CI 0.05-0.42 for daily vs. no consumption, adjusted for maternal BMI). In mice, maternal NNS caused elevated body weight, adiposity, and insulin resistance in offspring, especially in males (e.g., 47% and 15% increase in body fat for aspartame and sucralose vs. controls, p < 0.001). In cultured adipocytes, sucralose exposure at early stages of differentiation caused increased lipid accumulation and expression of adipocyte differentiation genes (e.g., C/EBP-α, FABP4, and FASN). These genes were also upregulated in adipose tissue of male mouse offspring born to sucralose-fed dams.

CONCLUSION

By triangulating evidence from humans, mice, and cultured adipocytes, this study provides new evidence that maternal NNS consumption during pregnancy may program obesity risk in offspring through effects on adiposity and adipocyte differentiation.

Early life programming in mice by maternal overnutrition: mechanistic insights and interventional approaches

Animal models have been indispensable in elucidating the potential causative mechanisms underlying the effects of maternal diet on offspring health. Of these, the mouse has been widely used to model maternal overnutrition and/or maternal obesity and to study its effects across one or more generations. This review discusses recent findings from mouse models, which resemble the human situation, i.e. overnutrition/obesity across pregnancy and lactation. It also highlights the importance of embryo transfer models in identifying critical developmental period(s) during which specific metabolic changes are programmed in the offspring. The mouse is also an excellent tool for maternal intervention studies aimed at elucidating the longer-term effects on the offspring and for defining possible maternal factors underling the programming of metabolic adversity in offspring. While knowledge of the mouse genome and the molecular tools available have allowed great progress to be made in the field, it is clear that we need to define if the effects on the offspring are mediated by maternal obesity per se or if specific components of the maternal metabolic environment are more important. We can then begin to identify at-risk offspring and to design more effective interventions for the mother and/or her child. This article is part of the theme issue 'Developing differences: early-life effects and evolutionary medicine'.

Early-life programming of adipose tissue

Worldwide obesity is increasing at an alarming rate in children and adolescents, with the consequent emergence of co-morbidities. Moreover, the maternal environment during pregnancy plays an important role in obesity, contributing to transgenerational transmission of the same and metabolic dysfunction. White adipose tissue represents a prime target of metabolic programming induced by maternal milieu. In this article, we review adipose tissue physiology and development, as well as maternal influences during the perinatal period that may lead to obesity in early postnatal life and adulthood. First, we describe the adipose tissue cell composition, distribution and hormonal action, together with the evidence of hormonal factors participating in fetal/postnatal programming. Subsequently, we describe the critical periods of adipose tissue development and the relationship of gestational and early postnatal life with healthy fetal adipose tissue expansion. Furthermore, we discuss the evidence showing that adipose tissue is an important target for nutritional, hormonal and epigenetic signals to modulate fetal growth. Finally, we describe nutritional, hormonal, epigenetic and microbiome changes observed in maternal obesity, and whether their disruption alters fetal growth and adiposity. The presented evidence supports the developmental origins of health and disease concept, which proposes that the homeostatic system is affected during gestational and postnatal development, impeding the ability to regulate body weight after birth, thereby resulting in adult obesity. Consequently, we anticipate that promoting a healthy early-life programming of adipose tissue and increasing the knowledge of the mechanisms by which maternal factors affect the health of future generations may offer novel strategies for explaining and addressing worldwide health problems such as obesity.

The effects of vitamin A supplementation during late-stage pregnancy on longissimus dorsi muscle tissue development, birth traits, and growth performance in postnatal Korean native calves

OBJECTIVE

This study investigated the effects of vitamin A (VA) supplementation during late-stage pregnancy on longissimus dorsi muscle tissue development, birth traits, and growth performance of postnatal Korean native calves.

METHODS

In the preliminary experiment, twenty-six pregnant cattle (initial body weight [BW] = 319 kg (standard deviation [SD] = 30.1; 1st parity) were randomly assigned to the control and treatment groups. The treatment group received VA supplementation at 24,000 IU/d from gestational day 225 until delivery. In the main experiment, twelve pregnant cattle (initial BW = 317 kg [SD = 31.3]; 1st parity) were treated with VA supplementation at 24,000 IU/d (gestational days 150 to 225) and at 78,000 IU/d (gestational day 225 until delivery). Serum VA levels were analyzed in pregnant cattle, and the growth performance, gene expression, and serum VA levels were analyzed in the offspring.

RESULTS

Serum VA levels in pregnant cattle decreased the late gestation in both experiments (p<0.001). In the main experiment, pregnant cattle at parturition and offspring at birth in the treatment group had higher serum VA levels than those in the control group (p<0.05). In the treatment groups, an increased birth weight was observed in the main experimental group (p = 0.022), and a tendency (p = 0.088) toward an increased birth weight was observed in the preliminary experimental group. However, no differences were observed in the feed intake, average daily gain, gain-to-feed ratio, or BW of 31-day-old calves. Gene expression was analyzed in longissimus dorsi muscles of 31-day-old calves. VA supplementation in pregnant cattle stimulated postnatal muscle development in offspring by elevating myogenic factor 5 (MYF5), MYF6, and myoblast determination levels (p<0.05). Moreover, preadipocyte-related marker genes such as extracellular signal-regulated kinase 2 and krüppel-like factor 2 were higher in the treatment group than in the control group (p<0.05).

CONCLUSION

VA supplementation (78,000 IU/d) in late-stage pregnant cattle maintained serum VA levels. In addition, 78,000 IU/d VA supplementation increased the birth weight and expression of genes related to muscle and preadipocyte development in offspring. Overall, 78,000 IU/d VA supplementation in pregnant cattle is beneficial to newborn calves.

Maternal regulation of SATB2 in osteo-progeniters impairs skeletal development in offspring

Nutritional status during intrauterine and/or early postnatal life has substantial influence on adult offspring health. Along these lines, there is a growing body of evidence illustrating that high fat diet (HFD)-induced maternal obesity can regulate fetal bone development. Thus, we investigated the effects of maternal obesity on both fetal skeletal development and mechanisms linking maternal obesity to osteoblast differentiation in offspring. Embryonic osteogenic calvarial cells (EOCCs) were isolated from fetuses at gestational day 18.5 (E18.5) of HFD-induced obese rat dams. We observed impaired differentiation of EOCCs to mature osteoblasts from HFD obese dams. ChIP-seq-based genome-wide localization of the repressive histone mark H3K27me3 (mediated via the polycomb histone methyltransferase, enhancer of zeste homologue 2 [Ezh2]) showed that this phenotype was associated with increased enrichment of H3K27me3 on the gene of SATB2, a critical transcription factor required for osteoblast differentiation. Knockdown of Ezh2 in EOCCs and ST2 cells increased SATB2 expression; while Ezh2 overexpression in EOCCs and ST2 cells decreased SATB2 expression. These data were consistent with experimental results showing strong association between H3K27me3, Ezh2, and SATB2 in cells from rats and humans. We have further presented that SATB2 mRNA and protein expression were increased in bones, and increased trabecular bone mass from pre-osteoblast specific Ezh2 deletion (Ezh2^flox/flox Osx-Cre⁺ cko) mice compared with those from control Cre⁺ mice. These findings indicate that maternal HFD-induced obesity may be associated with decreasing fetal pre-osteoblastic cell differentiation, under epigenetic control of SATB2 expression via Ezh2-dependent mechanisms.

Epigenetic Programming and Fetal Metabolic Programming

Fetal metabolic programming caused by the adverse intrauterine environment can induce metabolic syndrome in adult offspring. Adverse intrauterine environment introduces fetal long-term relatively irreversible changes in organs and metabolism, and thus causes fetal metabolic programming leading metabolic syndrome in adult offspring. Fetal metabolic programming of obesity and insulin resistance plays a key role in this process. The mechanism of fetal metabolic programming is still not very clear. It is suggested that epigenetic programming, also induced by the adverse intrauterine environment, is a critical underlying mechanism of fetal metabolic programming. Fetal epigenetic programming affects gene expression changes and cellular function through epigenetic modifications without DNA nucleotide sequence changes. Epigenetic modifications can be relatively stably retained and transmitted through mitosis and generations, and thereby induce the development of metabolic syndrome in adult offspring. This manuscript provides an overview of the critical role of epigenetic programming in fetal metabolic programming.

Impact of pregravid obesity on maternal and fetal immunity: Fertile grounds for reprogramming

Maternal pregravid obesity results in several adverse health outcomes during pregnancy, including increased risk of gestational diabetes, preeclampsia, placental abruption, and complications at delivery. Additionally, pregravid obesity and in utero exposure to high fat diet have been shown to have detrimental effects on fetal programming, predisposing the offspring to adverse cardiometabolic, endocrine, and neurodevelopmental outcomes. More recently, a deeper appreciation for the modulation of offspring immunity and infectious disease-related outcomes by maternal pregravid obesity has emerged. This review will describe currently available animal models for studying the impact of maternal pregravid obesity on fetal immunity and review the data from clinical and animal model studies. We also examine the burden of pregravid obesity on the maternal-fetal interface and the link between placental and systemic inflammation. Finally, we discuss future studies needed to identify key mechanistic underpinnings that link maternal inflammatory changes and fetal cellular reprogramming events.

Maternal obesity impairs fetal mitochondriogenesis and brown adipose tissue development partially via upregulation of miR-204-5p

Maternal obesity (MO) predisposes offspring to metabolic disorders, but the mechanisms remain poorly defined. Recent studies emphasize the importance of brown adipose tissue (BAT) in maintaining metabolic health, and MO was recently demonstrated to impair BAT thermogenic function in offspring. The current study aimed to investigate the mechanisms leading to the impairment in fetal BAT development due to MO. Female C57BL/6J mice were fed a control diet or a 60% high-fat diet for 10 weeks, mated and maintained on their respective diets during pregnancy. Fetal tissue was collected at E18.5, the late stage of pregnancy. Fetal BAT contained more triglycerides compared to the control, which was correlated with higher expression of white adipogenic markers. On the other hand, the expression of BAT markers was down-regulated in the MO fetal BAT. Based on RNA-sequencing analyses, genes related to mitochondriogenesis and myogenesis were found to be down-regulated, while those related to white adipocyte differentiation were up-regulated in MO fetal BAT. Because brown adipocytes are derived from myogenic progenitors, the down-regulation of myogenic genes might partially explain hampered brown adipogenesis in MO fetal BAT. Consistently, mitochondrial DNA and mitochondrial biogenesis markers were also down-regulated in MO fetal BAT. MicroRNA-sequencing identified that miR-204-5p expression was elevated in MO fetal BAT. This microRNA targeted the 3'-untranslated regions of PGC1α and Sirt1 mRNA to suppress their expression and impair mitochondriogenesis. In summary, MO impaired fetal BAT development through suppressing myogenesis and brown adipogenesis while enhancing white adipogenic commitment, and inhibited mitochondriogenesis partially through enhancing miR-204-5p expression.

Developmental Programming of Fetal Growth and Development

Maternal stressors that affect fetal development result in "developmental programming," which is associated with increased risk of various chronic pathologic conditions in the offspring, including metabolic syndrome; growth abnormalities; and reproductive, immune, behavioral, or cognitive dysfunction that can persist throughout their lifetime and even across subsequent generations. Developmental programming thus can lead to poor health, reduced longevity, and reduced productivity. Current research aims to develop management and therapeutic strategies to optimize fetal growth and development and thereby overcome the negative consequences of developmental programming, leading to improved health, longevity, and productivity of offspring.

Roles of Zinc Finger Protein 423 in Proliferation and Invasion of Cholangiocarcinoma through Oxidative Stress

Zinc finger protein 423 (ZNF423) is a transcriptional factor involved in the development and progression of cancers but has not yet been examined in cholangiocarcinoma (CCA), an oxidative stress-driven cancer of biliary epithelium. In this study, we hypothesized that oxidative stress mediated ZNF423 expression regulates its downstream genes resulting in CCA genesis. ZNF423 protein expression patterns and 8-oxodG (an oxidative stress marker) formation in CCA tissues were investigated using immunohistochemical analysis. The results showed that ZNF423 was overexpressed in CCA cells compared to normal bile duct cells adjacent of the tumor. Notably, ZNF423 expression was positively correlated with 8-oxodG formation. Moreover, ZNF423 expression in an immortalized cholangiocyte cell line (MMNK1) was increased by hydrogen peroxide-treatment, suggesting that oxidative stress induces ZNF423 expression. To investigate the roles of ZNF423 in CCA progression, ZNF423 mRNA was silenced using specific siRNA in CCA cell lines, KKU-100 and KKU-213. Silencing of ZNF423 significantly inhibits cell proliferation and invasion of both CCA cell lines. Taking all these results together, the present study denoted that ZNF423 is an oxidative stress-responsive gene with an oncogenic property contributing to the regulation of CCA genesis.

The role of DNA methylation in thermogenic adipose biology

The two types of thermogenic fat cells, beige and brown adipocytes, play a significant role in regulating energy homeostasis. Their development and thermogenesis are tightly regulated by dynamic epigenetic mechanisms, which could potentially be targeted to treat metabolic disorders such as obesity. However, we are just beginning to catalog and understand these dynamic changes. In this review, we will discuss the current understanding of the role of DNA (de)methylation events in beige and brown adipose biology in order to highlight the holes in our knowledge and to point the way forward for future studies.

GROWTH AND DEVELOPMENT SYMPOSIUM: STEM AND PROGENITOR CELLS IN ANIMAL GROWTH: The regulation of beef quality by resident progenitor cells1

The intramuscular adipose tissue deposition in the skeletal muscle of beef cattle is a highly desired trait essential for high-quality beef. In contrast, the excessive accumulation of crosslinked collagen in intramuscular connective tissue contributes to beef toughness. Recent studies revealed that adipose tissue and connective tissue share an embryonic origin in mice and may be derived from a common immediate bipotent precursor in mice and humans. Having the same linkages in the development of adipose tissue and connective tissue in beef, the lineage commitment and differentiation of progenitor cells giving rise to these tissues may directly affect beef quality. It has been shown that these processes are regulated by some key transcription regulators and are subjective to epigenetic modifications such as DNA methylation, histone modifications, and microRNAs. Continued exploration of relevant regulatory pathways is very important for the identification of mechanisms influencing meat quality and the development of proper management strategies for beef quality improvement.

Association of trimester-specific gestational weight gain with birth weight and fetal growth in a large community-based population

BACKGROUND

Previous studies showed that the association of gestational weight gain (GWG) with fetal birthweight and offspring developmental growth was unclear. The aim of this study is to investigate the respective effect of 1 kg of GWG during three trimesters on birthweight and offspring growth from birth to 3 years of age.

METHODS

We extracted the decoded information from the Maternal and Child Health Information Management System of Zhoushan Maternal and Child Health Hospital in Zhejiang, China from October 2001 to March 2015, and used multiple linear and logistic regression models.

RESULTS

This study included 20,232 women with a full-term singleton birth and 15,557 newborns who took regular health check-ups. Compared to that in the 2nd and 3rd trimester, 1 kg GWG increasing in the 1st trimester had the strongest positive association with higher birthweight, body weight, and height from 1 to 36 months. Their associations with BMI after birth were similar among the three trimesters. In addition, some positive dose-response effects found between quartiles of GWG in the 1st trimester and offspring body weight, as well as BMI. The 1 kg GWG in 1st trimester played the strongest role in contributing to birth weight and benefiting to body growth among children aged up to 3 years.

CONCLUSION

The 1 kg GWG in 1st trimester contributed more to birth weight and body development from birth to 3 years compared to the 2nd and 3rd trimesters. The possible beneficial effects of GWG in the 1st trimester on birthweight and offspring development in under/normal weight mothers are found.