DNA methylation: the pivotal interaction between early-life nutrition and glucose metabolism in later life

The Associations between Intakes of One-Carbon Metabolism-Related Vitamins and Breast Density among Young Women

BACKGROUND

Folate is the primary methyl donor and B vitamins are cofactors for one-carbon metabolism that maintain DNA integrity and epigenetic signatures implicated in carcinogenesis. Breast tissue is particularly susceptible to stimuli in early life. Only limited data are available on associations of one-carbon metabolism-related vitamin intake during youth and young adulthood with breast density, a strong risk factor for breast cancer.

METHODS

Over 18 years in the DISC and DISC06 Follow-up Study, diets of 182 young women were assessed by three 24-hour recalls on five occasions at ages 8 to 18 years and once at 25 to 29 years. Multivariable-adjusted linear mixed-effects regression was used to examine associations of intakes of one-carbon metabolism-related vitamins with MRI-measured percent dense breast volume (%DBV) and absolute dense breast volume (ADBV) at ages 25 to 29 years.

RESULTS

Folate intake in youth was inversely associated with %DBV (Ptrend = 0.006) and ADBV (Ptrend = 0.02). These inverse associations were observed with intake during post-, though not premenarche. In contrast, premenarche vitamin B2 intake was positively associated with ADBV (Ptrend < 0.001). Young adult folate and vitamin B6 intakes were inversely associated with %DBV (all Ptrend ≤ 0.04), whereas vitamins B6 and B12 were inversely associated with ADBV (all Ptrend ≤ 0.04).

CONCLUSIONS

Among these DISC participants intakes of one-carbon metabolism-related vitamins were associated with breast density. Larger prospective studies among diverse populations are needed to replicate these findings.

IMPACT

Our results suggest the importance of one-carbon metabolism-related vitamin intakes early in life with development of breast density and thereby potentially breast cancer risk later in life.

Mitochondrial dysfunction and epigenetics underlying the link between early-life nutrition and non-alcoholic fatty liver disease

Early-life malnutrition plays a critical role in foetal development and predisposes to metabolic diseases later in life, according to the concept of 'developmental programming'. Different types of early nutritional imbalance, including undernutrition, overnutrition and micronutrient deficiency, have been related to long-term metabolic disorders. Accumulating evidence has demonstrated that disturbances in nutrition during the period of preconception, pregnancy and primary infancy can affect mitochondrial function and epigenetic mechanisms. Moreover, even though multiple mechanisms underlying non-alcoholic fatty liver disease (NAFLD) have been described, in the past years, special attention has been given to mitochondrial dysfunction and epigenetic alterations. Mitochondria play a key role in cellular metabolic functions. Dysfunctional mitochondria contribute to oxidative stress, insulin resistance and inflammation. Epigenetic mechanisms have been related to alterations in genes involved in lipid metabolism, fibrogenesis, inflammation and tumorigenesis. In accordance, studies have reported that mitochondrial dysfunction and epigenetics linked to early-life nutrition can be important contributing factors in the pathogenesis of NAFLD. In this review, we summarise the current understanding of the interplay between mitochondrial dysfunction, epigenetics and nutrition during early life, which is relevant to developmental programming of NAFLD.

Promotion of Pregnant Merino Ewes' Welfare with the Introduction of a Drought- and High-Temperature-Resistant Cereal into Their Diet: Analysis of Tritordeum Meadow

Tritordeum is a new cereal resistant to drought and high temperatures, and it is a very healthy crop. The aim of this study was to compare two different diets (tritordeum meadow vs. oat meadow) for grazing pregnant ewes to determine if there was any effect on the objective physiological indicators of animal welfare. A total of 150 pregnant Merino ewes (3-5 years) were randomly divided into two groups (n = 75 each) to be fed with two different meadows, being evaluated during the spring season. Red blood cells count, haemoglobin, packed cell volume, white blood cell count, neutrophiles/lymphocytes ratio, lactate dehydrogenase, creatinine phosphokinase, aspartate aminotransferase, glucose, cortisol, total plasma proteins, albumin, globulins, albumin/globulins ratio, alkaline phosphatase, glutamate dehydrogenase, IgA, and IgG were determined. Overall, the results of this study indicate that the welfare of pregnant ewes fed with tritordeum meadow was better than that of pregnant ewes fed with oat meadow. Tritordeum meadow had a positive influence on the physiological parameters of animal welfare studied in pregnant Merino ewes. Therefore, tritordeum meadow can be considered a functional feed, as it has a beneficial effect on health beyond its basic nutritional value. Farmers are recommended to feed a cereal such as tritordeum grassland to their sheep, as it not only ensures that the animals benefit from all the nutrients, but also prevents diseases and improves their quality of life. In addition, the cereal's resistance to fungal diseases makes it suitable for use in sustainable production systems with a reduced environmental footprint.

Obesity, Cardiovascular and Neurodegenerative Diseases: Potential Common Mechanisms

The worldwide increase in the incidence of obesity and cardiovascular and neurodegenerative diseases, e.g. Alzheimer's disease, is related to many factors, including an unhealthy lifestyle and aging populations. However, the interconnection between these diseases is not entirely clear, and it is unknown whether common mechanisms underlie these conditions. Moreover, there are currently no fully effective therapies for obesity and neurodegeneration. While there has been extensive research in preclinical models addressing these issues, the experimental findings have not been translated to the clinic. Another challenge relates to the time of onset of individual diseases, which may not be easily identified, since there are no specific indicators or biomarkers that define disease onset. Hence knowing when to commence preventive treatment is unclear. This is especially pertinent in neurodegenerative diseases, where the onset of the disease may be subtle and occur decades before the signs and symptoms manifest. In metabolic and cardiovascular disorders, the risk may occur in-utero, in line with the concept of fetal programming. This review provides a brief overview of the link between obesity, cardiovascular and neurodegenerative diseases and discusses potential common mechanisms including the role of the gut microbiome.

New Insights and Potential Therapeutic Interventions in Metabolic Diseases

Endocrine homeostasis and metabolic diseases have been the subject of extensive research in recent years. The development of new techniques and insights has led to a deeper understanding of the mechanisms underlying these conditions and opened up new avenues for diagnosis and treatment. In this review, we discussed the rise of metabolic diseases, especially in Western countries, the genetical, psychological, and behavioral basis of metabolic diseases, the role of nutrition and physical activity in the development of metabolic diseases, the role of single-cell transcriptomics, gut microbiota, epigenetics, advanced imaging techniques, and cell-based therapies in metabolic diseases. Finally, practical applications derived from this information are made.

Bazi Bushen mitigates epigenetic aging and extends healthspan in naturally aging mice

Bazi Bushen (BZBS), a traditional Chinese medicine, has been proven effective in the treatment of age-related disease in mouse models. However, whether its therapeutic effects are due to antiaging mechanism has not yet been explored. In the present study, we investigated the antiaging effects of BZBS in naturally aging mice by using behavioral tests, liver DNA methylome sequencing, methylation age estimation, and frailty index assessment. The methylome analysis revealed a decrease of mCpG levels in the aged mouse liver. BZBS treatment tended to restore age-associated methylation decline and prune the methylation pattern toward that of young mice. More importantly, BZBS significantly rejuvenated methylation age of the aged mice, which was computed by an upgraded DNA methylation clock. These results were consistent with enhanced memory and muscular endurance, as well as decreased frailty score and liver pathological changes. KEGG analysis together with aging-related database screening identified methylation-targeted pathways upon BZBS treatment, including oxidative stress, DNA repair, MAPK signaling, and inflammation. Upregulation of key effectors and their downstream effects on elevating Sod2 expression and diminishing DNA damage were further investigated. Finally, in vitro experiments with senescent HUVECs proved a direct effect of BZBS extracts on the regulation of methylation enzymes during cellular aging. In summary, our work has revealed for the first time the antiaging effects of BZBS by slowing the methylation aging. These results suggest that BZBS might have great potential to extend healthspan and also explored the mechanism of BZBS action in the treatment of age-related diseases.

Long-term voluntary exercise inhibited AGE/RAGE and microglial activation and reduced the loss of dendritic spines in the hippocampi of APP/PS1 transgenic mice

Alzheimer's disease (AD) is closely related to hippocampal synapse loss, which can be alleviated by running exercise. However, further studies are needed to determine whether running exercise reduces synapse loss in the hippocampus in an AD model by regulating microglia. Ten-month-old male wild-type mice and APP/PS1 mice were randomly divided into control and running groups. All mice in the running groups were subjected to voluntary running exercise for four months. After the behavioral tests, immunohistochemistry, stereological methods, immunofluorescence staining, 3D reconstruction, western blotting and RNA-Seq were performed. Running exercise improved the spatial learning and memory abilities of APP/PS1 mice and increased the total number of dendritic spines, the levels of the PSD-95 and Synapsin Ia/b proteins, the colocalization of PSD-95 and neuronal dendrites (MAP-2) and the number of PSD-95-contacting astrocytes (GFAP) in the hippocampi of APP/PS1 mice. Moreover, running exercise reduced the relative expression of CD68 and Iba-1, the number of Iba-1⁺ microglia and the colocalization of PSD-95 and Iba-1⁺ microglia in the hippocampi of APP/PS1 mice. The RNA-Seq results showed that some differentially expressed genes (DEGs) related to the complement system (Cd59b, Serping1, Cfh, A2m, and Trem2) were upregulated in the hippocampi of APP/PS1 mice, while running exercise downregulated the C3 gene. At the protein level, running exercise also reduced the expression of advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGE), C1q and C3 in the hippocampus and AGEs and RAGE in hippocampal microglia in APP/PS1 mice. Furthermore, the Col6a3, Scn5a, Cxcl5, Tdg and Clec4n genes were upregulated in the hippocampi of APP/PS1 mice but downregulated after running, and these genes were associated with the C3 and RAGE genes according to protein-protein interaction (PPI) analysis. These findings indicate that long-term voluntary exercise might protect hippocampal synapses and affect the function and activation of microglia, the AGE/RAGE signaling pathway in microglia and the C1q/C3 complement system in the hippocampus in APP/PS1 mice, and these effects may be related to the Col6a3, Scn5a, Cxcl5, Tdg and Clec4n genes. The current results provide an important basis for identifying targets for the prevention and treatment of AD.

Current challenges and future implications of exploiting the omics data into nutrigenetics and nutrigenomics for personalized diagnosis and nutrition-based care

Nutrigenetics and nutrigenomics, combined with the omics technologies, are a demanding and an increasingly important field in personalizing nutrition-based care to understand an individual's response to nutrition-guided therapy. Omics is defined as the analysis of the large data sets of the biological system featuring transcriptomics, proteomics, and metabolomics and providing new insights into cell regulation. The effect of combining nutrigenetics and nutrigenomics with omics will give insight into molecular analysis, as human nutrition requirements vary per individual. Omics measures modest intraindividual variability and is critical to exploit these data for use in the development of precision nutrition. Omics, combined with nutrigenetics and nutrigenomics, is instrumental in the creation of goals for improving the accuracy of nutrition evaluations. Although dietary-based therapies are provided for various clinical conditions such as inborn errors of metabolism, limited advancement has been done to expand the omics data for a more mechanistic understanding of cellular networks dependent on nutrition-based expression and overall regulation of genes. The greatest challenge remains in the clinical sector to integrate the current data available, overcome the well-established limits of self-reported methods in research, and provide omics data, combined with nutrigenetics and nutrigenomics research, for each individual. Hence, the future seems promising if a design for personalized, nutrition-based diagnosis and care can be implemented practically in the health care sector.

The effects of epigenetic age and its acceleration on surface area, cortical thickness, and volume in young adults

DNA methylation age has been used in recent studies as an epigenetic marker of accelerated cellular aging, whose contribution to the brain structural changes was lately acknowledged. We aimed to characterize the association of epigenetic age (i.e. estimated DNA methylation age) and its acceleration with surface area, cortical thickness, and volume in healthy young adults. Using the multi-tissue method (Horvath S. DNA methylation age of human tissues and cell types. 2013. Genome Biol 14), epigenetic age was computed with saliva sample. Epigenetic age acceleration was derived from residuals after adjusting epigenetic age for chronological age. Multiple regression models were computed for 148 brain regions for surface area, cortical thickness, and volume using epigenetic age or accelerated epigenetic age as a predictor and controlling for sex. Epigenetic age was associated with surface area reduction of the left insula. It was also associated with cortical thinning and volume reduction in multiple regions, with prominent changes of cortical thickness in the left temporal regions and of volume in the bilateral orbital gyri. Finally, accelerated epigenetic age was negatively associated with right cuneus gyrus volume. Our findings suggest that understanding the mechanisms of epigenetic age acceleration in young individuals may yield valuable insights into the relationship between epigenetic aging and the cortical change and on the early development of neurocognitive pathology among young adults.

DNA methylation of pck1 might contribute to the programming effects of early high-carbohydrate diets feeding to the glucose metabolism across two generations in zebrafish (Danio rerio)

The purpose of this study is to assess the effects of early high-carbohydrate stimulus on glucose metabolism in zebrafish (Danio rerio) over two generations and explore the mechanisms that explain those nutritional programming effects via epigenetic modifications. The larvae were delivered a high-carbohydrate diet (53.66%) that was used as an early nutritional stimulus from the first feeding to the end of the yolk sac (FF) and 5 days after yolk-sac exhaustion (YE). The larvae (F0) and their offspring (F1) were then both fed the control diet (22.69%) until adulthood (15 weeks), and they were challenged with a high-carbohydrate diet (35.36%) at the 16th week. The results indicated that early stimulus immediately raised the mRNA levels of genes involved in glycolysis and gluconeogenesis. At the end of F0 challenge, both treatment groups decreased the plasma glucose levels, increased the expression levels of glucokinase (gck), and inhibited the mRNA during gluconeogenesis. When challenged in F1, the glucose levels were lower in FF (F1), and the mRNA levels of phosphoenolpyruvate carboxykinase 1 (pck1) were decreased in FF (F1) and YE (F1). Besides, in both experimental groups (F0 and F1), the CpG island of pck1 maintained lower levels of hypermethylated expression from F0 adult, 24 h post-fertilization embryo, to F1 adult. In conclusion, these results indicated that an early high-carbohydrate stimulus could significantly reprogram glucose metabolism in adult zebrafish, that those modifications could be partially transmitted to the next generation, and that the DNA methylation of pck1 might work as a stable epigenetic marker to contribute to those processes.

Prenatal ozone exposure programs a sexually dimorphic susceptibility to high-fat diet in adolescent Long Evans rats

Altered fetal growth, which can occur due to environmental stressors during pregnancy, may program a susceptibility to metabolic disease. Gestational exposure to the air pollutant ozone is associated with fetal growth restriction in humans and rodents. However, the impact of this early life ozone exposure on offspring metabolic risk has not yet been investigated. In this study, fetal growth restriction was induced by maternal inhalation of 0.8 ppm ozone on gestation days 5 and 6 (4 hr/day) in Long Evans rats. To uncover any metabolic inflexibility, or an impaired ability to respond to a high-fat diet (HFD), a subset of peri-adolescent male and female offspring from filtered air or ozone exposed dams were fed HFD (45% kcal from fat) for 3 days. By 6 weeks of age, male and female offspring from ozone-exposed dams were heavier than offspring from air controls. Furthermore, offspring from ozone-exposed dams had greater daily caloric consumption and reduced metabolic rate when fed HFD. In addition to energy imbalance, HFD-fed male offspring from ozone-exposed dams had dyslipidemia and increased adiposity, which was not evident in females. HFD consumption in males resulted in the activation of the protective 5'AMP-activated protein kinase (AMPKα) and sirtuin 1 (SIRT1) pathways in the liver, regardless of maternal exposure. Unlike males, ozone-exposed female offspring failed to activate these pathways, retaining hepatic triglycerides following HFD consumption that resulted in increased inflammatory gene expression and reduced insulin signaling genes. Taken together, maternal ozone exposure in early pregnancy programs impaired metabolic flexibility in offspring, which may increase susceptibility to obesity in males and hepatic dysfunction in females.

Milk Exosomal microRNAs: Postnatal Promoters of β Cell Proliferation but Potential Inducers of β Cell De-Differentiation in Adult Life

Pancreatic β cell expansion and functional maturation during the birth-to-weaning period is driven by epigenetic programs primarily triggered by growth factors, hormones, and nutrients provided by human milk. As shown recently, exosomes derived from various origins interact with β cells. This review elucidates the potential role of milk-derived exosomes (MEX) and their microRNAs (miRs) on pancreatic β cell programming during the postnatal period of lactation as well as during continuous cow milk exposure of adult humans to bovine MEX. Mechanistic evidence suggests that MEX miRs stimulate mTORC1/c-MYC-dependent postnatal β cell proliferation and glycolysis, but attenuate β cell differentiation, mitochondrial function, and insulin synthesis and secretion. MEX miR content is negatively affected by maternal obesity, gestational diabetes, psychological stress, caesarean delivery, and is completely absent in infant formula. Weaning-related disappearance of MEX miRs may be the critical event switching β cells from proliferation to TGF-β/AMPK-mediated cell differentiation, whereas continued exposure of adult humans to bovine MEX miRs via intake of pasteurized cow milk may reverse β cell differentiation, promoting β cell de-differentiation. Whereas MEX miR signaling supports postnatal β cell proliferation (diabetes prevention), persistent bovine MEX exposure after the lactation period may de-differentiate β cells back to the postnatal phenotype (diabetes induction).

Parental high-fat high-sugar diet programming and hypothalamus adipose tissue axis in male Wistar rats

PURPOSE

Maternal nutrition during early development and paternal nutrition pre-conception can programme offspring health status. Hypothalamus adipose axis is a target of developmental programming, and paternal and maternal high-fat, high-sugar diet (HFS) may be an important factor that predisposes offspring to develop obesity later in life. This study aims to investigate Wistar rats' maternal and paternal HFS differential contribution on the development, adiposity, and hypothalamic inflammation in male offspring from weaning until adulthood.

METHODS

Male progenitors were fed a control diet (CD) or HFS for 10 weeks before mating. After mating, dams were fed CD or HFS only during pregnancy and lactation. Forming the following male offspring groups: CD-maternal and paternal CD; MH-maternal HFS and paternal CD; PH-maternal CD and paternal HFS; PMH-maternal and paternal HFS. After weaning, male offspring were fed CD until adulthood.

RESULTS

Maternal HFS diet increased weight, visceral adiposity, and serum total cholesterol levels, and decreased hypothalamic weight in weanling male rats. In adult male offspring, maternal HFS increased weight, glucose levels, and hypothalamic NFκBp65. Paternal HFS diet lowered hypothalamic insulin receptor levels in weanling offspring and glucose and insulin levels in adult offspring. The combined effects of maternal and paternal HFS diets increased triacylglycerol, leptin levels, and hypothalamic inflammation in weanling rats, and increased visceral adiposity in adulthood.

CONCLUSION

Male offspring intake of CD diet after weaning reversed part of the effects of parental HFS diet during the perinatal period. However, maternal and paternal HFS diet affected adiposity and hypothalamic inflammation, which remained until adulthood.

Dietary fat intake during early pregnancy is associated with cord blood DNA methylation at IGF2 and H19 genes in newborns

Maternal fat intake during pregnancy affects fetal growth, but mechanisms underlying this relationship are unclear. We performed an exploratory study of the associations of fat consumption during pregnancy with cord blood DNA methylation of the insulin-like growth factor 2 (IGF2) and H19 genes. We used data from 96 uncomplicated full-term pregnancies of mothers of whom majority had normal body mass index (BMI) (66%) in Project Viva, a prospective pre-birth cohort. We assessed maternal diet with validated food frequency questionnaires during the first and second trimesters and measured DNA methylation in segments of the IGF2- and H19-differentially methylated regions (DMRs) by pyrosequencing DNA extracted from umbilical cord blood samples. Mean (SD) age was 32.8 (4.1) years and prepregnancy BMI was 24.0 (4.4) kg/m² . Mean DNA methylation was 56.3% (3.9%) for IGF2-DMR and 44.6% (1.9%) for H19-DMR. Greater first trimester intake of omega-6 polyunsaturated fat (effect per 1% of calories at the expense of carbohydrates) was associated with lower DNA methylation of IGF2-DMR (-1.2%; 95% confidence interval [CI]: -2.2%, -0.2%) and higher DNA methylation at H19-DMR (0.8%; 95% CI: 0.3%, 1.3%). On the other hand, greater first trimester intake of omega-3 polyunsaturated fat was associated with lower DNA methylation of the H19-DMR (-4.3%; 95% CI: -7.9%, -0.8%). We did not find significant associations of IGF2 and H19 methylation with IGF2 cord blood levels. Our findings suggest that early prenatal fat intake (omega-3, omega-6, and saturated fatty acids) may influence DNA methylation at the IGF2 and H19 locus, which could impact fetal development and long-term health.

Early-life nutrition and metabolic disorders in later life: a new perspective on energy metabolism

Type 2 diabetes mellitus and metabolic disorders have become an epidemic globally. However, the pathogenesis remains largely unclear and the prevention and treatment are still limited. In addition to environmental factors during adulthood, early life is the critical developmental window with high tissue plasticity, which might be modified by external environmental cues. Substantial evidence has demonstrated the vital role of early-life nutrition in programming the metabolic disorders in later life. In this review, we aim to overview the concepts of fetal programming and investigate the effects of early-life nutrition on energy metabolism in later life and the potential epigenetic mechanism. The related studies published on PubMed database up to March 2020 were included. The results showed that both maternal overnutrition and undernutrition increased the riskes of metabolic disorders in offspring and epigenetic modifications, including DNA methylation, miRNAs, and histone modification, might be the vital mediators. The beneficial effects of early-life lifestyle modifications as well as dietary and nutritional interventions on these deleterious metabolic remolding were initially observed. Overall, characterizing the early-life malnutrition that reshapes metabolic disease trajectories may yield novel targets for early prevention and intervention and provide a new point of view to the energy metabolism.

Placental superoxide dismutase 3 mediates benefits of maternal exercise on offspring health

Poor maternal diet increases the risk of obesity and type 2 diabetes in offspring, adding to the ever-increasing prevalence of these diseases. In contrast, we find that maternal exercise improves the metabolic health of offspring, and here, we demonstrate that this occurs through a vitamin D receptor-mediated increase in placental superoxide dismutase 3 (SOD3) expression and secretion. SOD3 activates an AMPK/TET signaling axis in fetal offspring liver, resulting in DNA demethylation at the promoters of glucose metabolic genes, enhancing liver function, and improving glucose tolerance. In humans, SOD3 is upregulated in serum and placenta from physically active pregnant women. The discovery of maternal exercise-induced cross talk between placenta-derived SOD3 and offspring liver provides a central mechanism for improved offspring metabolic health. These findings may lead to novel therapeutic approaches to limit the transmission of metabolic disease to the next generation.

Food intake in early life and epigenetic modifications of pro-opiomelanocortin expression in arcuate nucleus

The prevalence of obesity is increasing in nowadays societies and, despite being a multifactorial disease, it has a significant correlation with food intake. The control of food intake is performed by neurons of the arcuate nucleus of the hypothalamus (ARC), which secret orexigenic and anorexigenic neuropeptides, such as proopiomelanocortin (POMC), under stimulation of, e.g., ghrelin, insulin, and leptin. Insulin, uses inositol 1,4,5-trisphosphate/serine-threonine kinase (IP3/Akt) pathways and stimulates the exclusion of (Forkhead box protein O1) FOXO1 from the nucleus and thereby does the inactivation of the inhibition of POMC expression, while Leptin stimulates signal transducer and activator of transcription 3 (STAT3) phosphorylation and POMC expression. Epigenetic modifications of the synthesis of these neuropeptides can lead to an increased caloric intake, which, in turn, is an important risk factor for obesity and its comorbidities. Epigenetic modifications are reversible, so the search for epigenetic targets has significant scientific and therapeutic appeal. In this review, we synthesize the effect of food intake on the epigenetic modifications of Neuropeptide Y and Pro-opiomelanocortin of ARC and its relationships with obesity development and comorbidities. We found that there is no consensus on the methylation of neuropeptides when the evaluations are carried out in different promoters. Based on reports carried on in the early life in laboratory animals, which is the timeline that the vast majority of author used to study this topic, chronic inflammation, defects in insulin and leptin signaling may be linked to changes occurring in the phosphoinositide 3-kinase/Akt (PI3K/Akt) and/or STAT3/SOCS3 (cytokine signaling 3) pathways. In its turn, the epigenetic modifications related to increased food intake and reduced energy expenditure may be associated with PI3K/Akt and STAT3/SOCS3 signaling disruption and Pro-opiomelanocortin expression.

Impact of Early Nutrition, Physical Activity and Sleep on the Fetal Programming of Disease in the Pregnancy: A Narrative Review

Early programming is the adaptation process by which nutrition and environmental factors alter development pathways during prenatal growth, inducing changes in postnatal metabolism and diseases. The aim of this narrative review, is evaluating the current knowledge in the scientific literature on the effects of nutrition, environmental factors, physical activity and sleep on development pathways. If in utero adaptations were incorrect, this would cause a mismatch between prenatal programming and adulthood. Adequate caloric intake, protein, mineral, vitamin, and long-chain fatty acids, have been noted for their relevance in the offspring brain functions and behavior. Fetus undernutrition/malnutrition causes a delay in growth and have detrimental effects on the development and subsequent functioning of the organs. Pregnancy is a particularly vulnerable period for the development of food preferences and for modifications in the emotional response. Maternal obesity increases the risk of developing perinatal complications and delivery by cesarean section and has long-term implications in the development of metabolic diseases. Physical exercise during pregnancy contributes to overall improved health post-partum. It is also interesting to highlight the relevance of sleep problems during pregnancy, which influence adequate growth and fetal development. Taking into account these considerations, we conclude that nutrition and metabolic factors during early life play a key role of health promotion and public health nutrition programs worldwide to improve the health of the offspring and the health costs of hospitalization.

Exploring the Role of Maternal Nutritional Epigenetics in Congenital Heart Disease

Congenital heart disease (CHD) is one of the major debilitating birth defects resulting in significant impact on neonatal and child mortality globally. The etiology of CHD is complex and multifactorial. Many causative genes responsible for CHDs have been identified from the familial forms previously. Still, the non-Mendelian inheritance and predominant sporadic cases have stimulated research to understand the epigenetic basis and environmental impact on the incidence of CHD. The fetal epigenetic programming affecting cardiac development is susceptible to the availability of key dietary factors during the crucial periconceptional period. This article highlights the need and importance of in-depth research in the new emerging area of maternal nutritional epigenetics and CHD. It summarizes the current research and underlines the limitations in these types of studies. This review will benefit the future research on nutrition as a modifiable environmental factor to decrease the incidence of CHD.

Identification of modifiable pre- and postnatal dietary and environmental exposures associated with owner-reported canine atopic dermatitis in Finland using a web-based questionnaire

A cross-sectional hypothesis generating study was performed to investigate modifiable exposures such as whether feeding pattern (a non-processed meat based diet, NPMD, or an ultra-processed carbohydrate based diet, UPCD), certain environmental factors and their timing of exposure might be associated with the development of canine atopic dermatitis (CAD). Also, genetic and demographic factors were tested for associations with CAD. The data was collected from the validated internet-based DogRisk food frequency questionnaire in Finland. A total of 2236 dogs were eligible for the study (the owners reported 406 cases and 1830 controls). Our main interest was to analyze modifiable early risk factors of CAD, focusing on nutritional and environmental factors. We tested four early life periods; prenatal, neonatal, early postnatal and late postnatal periods. Twenty-two variables were tested for associations with CAD using logistic regression analysis. From the final models we identified novel dietary associations with CAD: the NPMD during the prenatal and early postnatal periods had a significant negative association with the incidence of CAD in adult dogs (age above 1 year). Oppositely, UPCD was associated with a significantly higher risk for CAD incidence. Other variables that were associated with a significantly lower risk for CAD were maternal deworming during pregnancy, sunlight exposure during early postnatal period, normal body condition score during the early postnatal period, the puppy being born within the same family that it would stay in, and spending time on a dirt or grass surface from 2 to 6 months. Also, the genetic factors regarding maternal history of CAD, allergy-prone breeds and more than 50% white-colored coat all showed a significant positive association with CAD incidence in agreement with previous findings. Although no causality can be established, feeding NPMD early in life seemed to be protective against CAD, while UPCD could be considered a risk factor. Prospective intervention studies are needed to establish the causal effects of the protective role of NPMD on prevalence of CAD during the fetal and early postnatal life.

Lean body mass accretion is elevated in response to dietary vitamin D: A dose-response study in female weanling rats

Vitamin D status positively relates to lean body mass in infants. This study tested the effect of vitamin D on body composition and growth-related hormones. It was hypothesized that low vitamin D status programs for higher fat mass accretion. Female weanling Sprague-Dawley rats (4 weeks; n = 6/diet) were randomized to AIN-93G diets with modified vitamin D contents for 8 weeks: group 1 (1 IU vitamin D₃/g diet), group 2 (2 IU vitamin D₃/g diet), and group 3 (4 IU vitamin D₃/g diet). At week 0, 4, and 8 of study, measurements included: serum 25(OH)D₃, IGF-1, IGFBP3, leptin, and whole body composition assessed with DXA. Differences among groups were tested using mixed model ANOVA with Tukey's post hoc t-tests. No differences were observed in baseline body composition and biomarkers, nor did body weight and food intake differ over the study. At week 8, serum 25(OH)D₃ in group 3 was higher (P < .0001) compared to groups 1 and 2. At 8 weeks, lean mass (P < .05) and lean mass accretion (P < .05) were significantly higher in groups 2 and 3 compared to group 1. Serum IGF-1 concentration declined over time (P < .001) with smaller declines at week 8 in group 3 (P < .05). Serum IGFBP3 concentration was lower at week 4 in group 2 compared to groups 1 and 3. Serum leptin concentration and fat mass were not affected by diet. These results suggested that the achievement of higher vitamin D status may support a lean body phenotype without altering weight gain.

DNA methylome of human neonatal umbilical cord: Enrichment of differentially methylated regions compared to umbilical cord blood DNA at transcription factor genes involved in body patterning and effects of maternal folate deficiency or children's sex

The DOHaD (developmental origins of health and disease) hypothesis claims that fetal malnutrition or exposure to environmental pollutants may affect their lifelong health. Epigenetic changes may play significant roles in DOHaD; however, access to human fetuses for research has ethical and technical hurdles. Umbilical cord blood (CB) has been commonly used as an epigenetic surrogate of fetuses, but it does not provide direct evidence of fetal exposure to pollutants. Here, we propose umbilical cord tissue (UC), which accumulates substances delivered to fetuses during gestation, as an alternative surrogate for epigenetic studies on fetuses. To explore the feasibility to examine UC epigenome by deep sequencing, we determined CpG methylation profiles of human postnatal UC by reduced representation bisulfite sequencing. Principal component analysis clearly separated the DNA methylomes of UC and CB pairs isolated from the same newborn (n = 10). Although all UC chromosomes were modestly hypomethylated compared to CB chromosomes, GO analysis revealed strong enrichment of differentially methylated regions (DMRs) at promoter-associated CpG islands in the HOX gene clusters and other genes encoding transcription factors involved in determination of the body pattern. DNA methylomes of UC autosomes were largely comparable between males and females. Deficiency of folate during pregnancy has been suggested to affect fetal DNA methylation to cause congenital anomalies. Whereas DNA methylome of UC was not significantly affected by early-gestational (12 weeks) low levels of maternal plasma folate (< 8 ng/ml, n = 10) compared to controls (>19 ng/mL, n = 10), two specific loci of LTR12C endogenous retroviruses in chromosome 12 were significantly hypermethylated in the low-folate group. Our study suggests that UC is useful as an alternative surrogate for studying environmental effects on DNA methylation in human fetuses, compensating CB by providing additional information about epigenetic regulation of genes involved in developmental body patterning and endogenous retroviruses.

Methylation profile of the ADRB3 gene and its association with lipid profile and nutritional status in adults

BACKGROUND

Defects in DNA methylation have been shown to be associated with metabolic diseases such as obesity, dyslipidemia, and hypercholesterolemia. To analyze the methylation profile of the ADRB3 gene and correlate it with lipid profile, lipid intake, and oxidative stress based on malondialdehyde (MDA) and total antioxidant capacity (TAC), homocysteine and folic acid levels, nutritional status, lifestyle, and socioeconomic variables in an adult population. A cross-sectional epidemiological study representative of the East and West regions of the municipality of João Pessoa, Paraíba state, Brazil, enrolled 265 adults of both genders. Demographic, lifestyle, and socioeconomic questionnaires and a 24-h recall questionnaire were applied by trained interviewers' home. Nutritional and biochemical evaluation (DNA methylation, lipid profile, MDA, TAC, homocysteine and folic acid levels) was performed.

RESULTS

DNA hypermethylation of the ADRB3 gene, analyzed in leukocytes, was present in 50% of subjects and was associated with a higher risk of being overweight (OR 3.28; p = 0.008) or obese (OR 3.06; p = 0.017), a higher waist-hip ratio in males (OR 1.17; p = 0.000), greater intake of trans fats (OR 1.94; p = 0.032), higher LDL (OR 2.64; p = 0.003) and triglycerides (OR 1.81; p = 0.031), and higher folic acid levels (OR 1.85; p = 0.022).

CONCLUSIONS

These results suggest that epigenetic changes in the ADRB3 gene locus may explain the development of obesity and non-communicable diseases associated with trans-fat intake, altered lipid profile, and elevated folic acid. Because of its persistence, DNA methylation may have an impact in adults, in association with the development of non-communicable diseases. This study is the first population-based study of the ADRB3 gene, and the data further support evaluation of ADRB3 DNA methylation as an effective biomarker.

Association between maternal pre-delivery body mass index and offspring overweight/obesity at 1 and 2 years of age among residents of a suburb in Taiwan

Background

Overweight and obesity among children can cause metabolic syndrome in adulthood and are a significant public health issue. Some studies suggest that maternal pre-pregnancy body mass index (BMI) and excessive gestational weight gain during pregnancy are associated with overweight and obesity in offspring. However, it is difficult to collect information on accurate pre-pregnancy BMI and pregnancy weight gain for women living in areas where medical resources are scarce. Maternal pre-delivery BMI might be predictive of the risk of overweight and obesity among offspring of pregnant mothers living in suburban areas.

Methods

We retrospectively collected data on term neonates with appropriate weights for their gestational age born between April 2013 and October 2015. We excluded neonates with major congenital anomalies or diseases and incomplete data. Mothers with systemic diseases or drug abuse were also excluded. Offspring body weights and heights at 1- and 2-years-old were recorded. Maternal pre-delivery BMI was divided into following groups: <25, 25-29.9, and ≧30 kg/m².

Results

We included 261 mother-child pairs in this study. The BMIs of the offspring differed significantly among the three maternal pre-delivery BMI groups at the age of 2 years (15.18 ± 1.04, 15.83 ± 1.28, and 16.29 ± 1.61 kg/m², p < 0.001, respectively). After adjusting for potential cofounders possibly affecting weight using multivariate linear regression, the children's BMIs (adjusted 95% CI: 0.71 [0.31-1.11]; p = 0.001) and BMI percentiles (adjusted 95% CI 15.80 [7.32-24.28]; p < 0.001) at the age of 2 years were significantly higher in those born to mothers with pre-delivery BMIs of 25-29.9 kg/m² compared to mothers with pre-delivery BMIs <25 kg/m². Maternal pre-delivery BMI ≧30 kg/m² was significantly associated with increased BMIs (adjusted 95% CI: 1.17 [0.72-1.63]; p < 0.001) and BMI percentiles (adjusted 95% CI: 23.48 [13.87-33.09]; p < 0.001) in their children. A maternal pre-delivery BMI of 27.16 kg/m² was the optimal cut-off for predicting offspring overweight/obesity at the age of 2 years.

Discussion

Our results indicate that the maternal pre-delivery BMI was significantly associated with offspring BMI and weight gain at the age of 2 years. A maternal pre-delivery BMI of 27.16 kg/m² might be a useful predictor for estimating the risk of overweight or obesity in offspring at the age of 2 years.

Early Life Nutrition and Non Communicable Disease

The origin of some non communicable disease (NCDs) is in early life. Evidence has shown that early life nutrition is associated with the risk of developing chronic non communicable diseases. Pregnancy and infancy are the most critical stages that influence the risks of NCDs in childhood and adult life. Prenatal maternal undernutrition and low birth weight lead to obesity and increase the risk factors of cardiovascular disease and diabetes later in life. Nutrition is one of the easily modifiable environmental factors that may affect outcome of pregnancy, trajectory of growth, and immune system of the fetus and infant. Healthy eating behaviors associate with prevention of weight disorders in pediatric, non communicable diseases, and deficiencies of micronutrient.

Prenatal undernutrition suppresses sexual behavior in female rats

Infectious, psychological and metabolic stresses in the prenatal and early neonatal period induce long-lasting effects in physiological function and increase the risk of metabolic disorders later in life. We examined the sexual behavior of female rats that were subjected to undernutrition in the prenatal period. Eight pregnant rats were divided into two groups: a maternal normal nutrition group (mNN; n = 4) and a maternal undernutrition group (mUN; n = 4), which received 50% of the daily food intake amount of the mNN group from gestation day 13 to delivery. Nine and seven female offspring were randomly selected from the mNN and mUN groups, respectively. Vaginal opening (VO), estrous cycle length, sexual behavior and mRNA expression levels of the factors that regulate sexual behavior were observed. In the mUN group, VO day was later, the estrous cycle was longer, and the lordosis quotient and lordosis rating were lower than in the mNN group; such differences were not seen in other sexual performances, such as ear wiggles, darts, kick bouts and box. The hypothalamic mRNA expression level of progesterone receptor (PR) A + B and oxytocin (OT) were significantly lower in the mUN group than in the mNN group. These findings indicated that prenatal undernutrition disrupted puberty onset, the estrous cycle, sexual behavior and hypothalamic mRNA expression of PR and OT in female rat pups.

Maternal Protein Restriction Alters the Renal Ptger1 DNA Methylation State in SHRSP Offspring

We previously reported that maternal protein restriction (LP) during pregnancy increases salt sensitivity in offspring using the Stroke-Prone Spontaneously Hypertensive Rat (SHRSP). In the present study, we focus on DNA methylation profiles of prostaglandin E receptor 1 gene (ptger1), which is known to be associated with hypertension. We evaluated the ptger1 DNA methylation status via bisulfite sequencing, and analyzed the expression of ptger1-related genes. The results of these analyses showed that, compared to controls, the LP-S offspring exhibited both marked ptger1 hypermethylation, and significantly increased ptger1 expression. Moreover, they also exhibited significantly decreased expression of the downstream gene epithelial Na⁺ channel alpha (enacα). Interestingly, LP offspring that were provided with a standard water drinking supply (W) also exhibited increased ptger1 methylation and expression. Together, these results suggest that maternal protein restriction during pregnancy modulates the renal ptger1 DNA methylation state in SHRSP offspring, and thereby likely mediates ptger1 and enacα gene expression to induce salt sensitivity.

[Does Malnutrition during Fetal Life Have a Potential to Be a Precipitating Factor for Developmental Disorders?]

OBJECTIVES

The developmental origins of health and disease paradigm (DOHaD) is a concept that fetal environmental factors affect adult phenotypes. We performed experiments to evaluate the DOHaD theory in developmental disorders using mouse models.

METHODS

In vitro fertilization and embryo transfer techniques were used for mouse production. The AIN93G-control diet, which contains 20% protein (CD), 5% protein-restricted diet (PR), and PR with supplemental folic acid (FA) were provided as experimental diets to mothers. The body weights (BWs) of mothers and offspring, and the blood-clinical biochemistry results of mothers were examined. In addition, gene expression and genomic methylation in the brain of adult offspring and behavioral phenotypes of adult offspring were examined.

RESULTS

Pregnant mothers that consumed the protein-restricted diets, namely, PR and FA, exhibited reduction in BW. The values of protein-related parameters determined by blood-clinical biochemistry decreased in the PR fed groups. The BWs of neonates and adult offspring did not change. The offspring exposed to maternal hyponutrition exhibited increased activity in the home cage and enhanced fear and anxiety-like behavior. The adult offspring of the PR-fed group and FA-fed groups exhibited different patterns of mRNA expression and genomic methylation in the brain.

CONCLUSIONS

The maternal PR diet affected the progenies' behavioral phenotypes and epigenetic outcomes in the brain. However, the behavioral changes induced by maternal protein restriction were very slight. Hence, interactions between several genetic factors and environmental exposures such as maternal malnutrition may cause developmental and psychiatric disorders.

Time- and sex-dependent associations between prenatal alcohol exposure and placental global DNA methylation

AIM

Epigenetic changes, in particular in the placenta, may mediate the effects of prenatal alcohol exposure (PAE) on children's health. We examined the relationship between PAE patterns, based on dose and timing, and placental global DNA methylation.

METHODS

Using linear regression analysis, we examined the association between different PAE categories and placental global DNA methylation (n = 187), using the proxy measure of Alu-interspersed repeats.

RESULTS

Following adjustment for important covariates, we found no evidence of an association between PAE and placental global DNA methylation overall. However, when stratifying by newborn sex, PAE throughout pregnancy was associated with higher placental global DNA methylation (1.5%; p = 0.01) of male newborns.

CONCLUSION

PAE may have sex-specific effects on placental global DNA methylation if alcohol is consumed throughout pregnancy.

Exposure to elevated glucose concentrations alters the metabolomic profile of bovine blastocysts

Chronically high blood glucose concentrations are a characteristic of diabetes mellitus. Maternal diabetes affects the metabolism of early embryos and can cause a delay in development. To mimic maternal diabetes, bovine in vitro fertilization and embryo culture were performed in fertilization medium and culture medium containing 0.5, 2, 3, and 5 mM, glucose whereas under control conditions, the medium was glucose free (0 mM). Compared to control conditions (0 mM, 31%), blastocyst development was decreased to 23% with 0.5 and 2 mM glucose. Presence of 3 or 5 mM glucose in the medium resulted in decreased blastocyst rates (20% and 10% respectively). The metabolomic profile of resulting day 8 blastocysts was analysed by UPLC-MS/MS, and compared to that of blastocysts cultured in control conditions. Elevated glucose concentrations stimulated an increase in glycolysis and activity of the hexosamine pathway, which is involved in protein glycosylation. However, components of the tricarboxylic acid cycle, such as citrate and alpha-ketoglutarate, were reduced in glucose stimulated blastocysts, suggesting that energy production from pyruvate was inefficient. On the other hand, activity of the polyol pathway, an alternative route to energy generation, was increased. In short, cattle embryos exposed to elevated glucose concentrations during early development showed changes in their metabolomic profile consistent with the expectations of exposure to diabetic conditions.

Annual Research Review: DNA methylation as a mediator in the association between risk exposure and child and adolescent psychopathology

BACKGROUND

DNA methylation (DNAm) is a potential mechanism for propagating the effects of environmental exposures on child and adolescent mental health. In recent years, this field has experienced steady growth.

METHODS

We provide a strategic review of the current child and adolescent literature to evaluate evidence for a mediating role of DNAm in the link between environmental risks and psychopathological outcomes, with a focus on internalising and externalising difficulties.

RESULTS

Based on the studies presented, we conclude that there is preliminary evidence to support that (a) environmental factors, such as diet, neurotoxic exposures and stress, influence offspring DNAm, and that (b) variability in DNAm, in turn, is associated with child and adolescent psychopathology. Overall, very few studies have examined DNAm in relation to both exposures and outcomes, and almost all analyses have been correlational in nature.

CONCLUSIONS

DNAm holds potential as a biomarker indexing both environmental risk exposure and vulnerability for child psychopathology. However, the extent to which it may represent a causal mediator is not clear. In future, collection of prospective risk exposure, DNAm and outcomes - as well as functional characterisation of epigenetic findings - will assist in determining the role of DNAm in the link between risk exposure and psychopathology.

Maternal resveratrol consumption and its programming effects on metabolic health in offspring mechanisms and potential implications

A growing body of evidence has clearly demonstrated that maternal nutrition can strongly determine the susceptibility to the development of metabolic diseases in offspring. With the increasing prevalence of maternal overweight, obesity, and gestational diabetes mellitus, it yields enormous burden for individual and public health. Interventions during pregnancy have been proven to be challenging, with limited efficacy and low compliance. Resveratrol, as a natural polyphenolic compound, has a wide-range of beneficial properties, including potent antiobesogenic, antiatherosclerotic, and antidiabetic effects. However, the role of maternal resveratrol intake on metabolic health in offspring has not been extensively investigated. Therefore, the aim of this study was to review the effects of maternal resveratrol supplementation on metabolic health in offspring and its potential mechanisms.

Maternal Micronutrients, Omega-3 Fatty Acids and Gene Expression of Angiogenic and Inflammatory Markers in Pregnancy Induced Hypertension Rats

BACKGROUND AND AIMS

Preeclampsia is a disorder of pregnancy and is associated with inflammation and altered angiogenesis. The present study examines the effect of micronutrient and omega-3 fatty acid supplementation (individual, as well as combined) on genes involved in inflammation and angiogenesis, as well as global DNA methylation levels in a pregnancy induced hypertension (PIH) rat model.

METHODS

Pregnant Wistar rats were randomly assigned to six dietary groups: control, PIH (Pregnancy induced hypertension) Induced; PIH Induced with micronutrient supplements with vitamin B₁₂ (PIHB), folate (PIHF), omega-3 fatty acid (PIHO), and combined supplementation (PIHC) (micronutrients and omega-3 fatty acids). Half the dams were dissected on 20 d of gestation to collect placental tissue, and half were allowed to deliver normally on 22 d of gestation and were assigned to a postnatal control diet. The offspring were dissected at 3 month of age.

RESULTS

PIH induction increased the mRNA levels of the pro inflammatory cytokine IL-6 (p <0.01), while lowering the placental anti inflammatory cytokine IL-10 (p <0.05) at d20 of gestation. It also increased the expression of TNF-α (p <0.05) in the liver of 3 month old offspring. The combined supplementation of folic acid, vitamin B₁₂ and omega-3 fatty acids improved placental IL-10 levels and decreased TNF-α levels in offspring livers.

CONCLUSION

Our data indicate that a combined supplementation of vitamin B₁₂, folic acid and omega-3 fatty acid was useful for the better management of preeclampsia in an animal model.

DNA methylation and gene expression of TXNIP in adult offspring of women with diabetes in pregnancy

BACKGROUND

Fetal exposure to maternal diabetes increases the risk of type 2 diabetes (T2DM), possibly mediated by epigenetic mechanisms. Low blood TXNIP DNA methylation has been associated with elevated glucose levels and risk of T2DM, and increased skeletal muscle TXNIP gene expression was reported in subjects with impaired glucose metabolism or T2DM. Subcutaneous adipose tissue (SAT) and skeletal muscle play a key role in the control of whole body glucose metabolism and insulin action. The extent to which TXNIP DNA methylation levels are decreased and/or gene expression levels increased in SAT or skeletal muscle of a developmentally programmed at-risk population is unknown.

OBJECTIVE AND METHODS

The objective of this study was to investigate TXNIP DNA methylation and gene expression in SAT and skeletal muscle, and DNA methylation in blood, from adult offspring of women with gestational diabetes (O-GDM, n = 82) or type 1 diabetes (O-T1DM, n = 67) in pregnancy compared with offspring of women from the background population (O-BP, n = 57).

RESULTS

SAT TXNIP DNA methylation was increased (p = 0.032) and gene expression decreased (p = 0.001) in O-GDM, but these differences were attenuated after adjustment for confounders. Neither blood/muscle TXNIP DNA methylation nor muscle gene expression differed between groups.

CONCLUSION

We found no evidence of decreased TXNIP DNA methylation or increased gene expression in metabolic target tissues of offspring exposed to maternal diabetes. Further studies are needed to confirm and understand the paradoxical SAT TXNIP DNA methylation and gene expression changes in O-GDM subjects.

Milk disrupts p53 and DNMT1, the guardians of the genome: implications for acne vulgaris and prostate cancer

There is accumulating evidence that milk shapes the postnatal metabolic environment of the newborn infant. Based on translational research, this perspective article provides a novel mechanistic link between milk intake and milk miRNA-regulated gene expression of the transcription factor p53 and DNA methyltransferase 1 (DNMT1), two guardians of the human genome, that control transcriptional activity, cell survival, and apoptosis. Major miRNAs of milk, especially miRNA-125b, directly target TP53 and complex p53-dependent gene regulatory networks. TP53 regulates the expression of key genes involved in cell homeostasis such as FOXO1, PTEN, SESN1, SESN2, AR, IGF1R, BAK1, BIRC5, and TNFSF10. Nuclear interaction of p53 with DNMT1 controls gene silencing. The most abundant miRNA of milk and milk fat, miRNA-148a, directly targets DNMT1. Reduced DNMT1 expression further attenuates the activity of histone deacetylase 1 (HDAC1) involved in the regulation of chromatin structure and access to transcription. The presented milk-mediated miRNA-p53-DNMT1 pathway exemplified at the promoter regulation of survivin (BIRC5) provides a novel explanation for the epidemiological association between milk consumption and acne vulgaris and prostate cancer. Notably, p53- and DNMT1-targeting miRNAs of bovine and human milk survive pasteurization and share identical seed sequences, which theoretically allows the interaction of bovine miRNAs with the human genome. Persistent intake of milk-derived miRNAs that attenuate p53- and DNMT1 signaling of the human milk consumer may thus present an overlooked risk factor promoting acne vulgaris, prostate cancer, and other p53/DNMT1-related Western diseases. Therefore, bioactive miRNAs of commercial milk should be eliminated from the human food chain.

Connecting the Dots Between Fatty Acids, Mitochondrial Function, and DNA Methylation in Atherosclerosis

PURPOSE OF REVIEW

The quest for factors and mechanisms responsible for aberrant DNA methylation in human disease-including atherosclerosis-is a promising area of research. This review focuses on the role of fatty acids (FAs) as modulators of DNA methylation-in particular the role of mitochondrial beta-oxidation in FA-induced changes in DNA methylation during the progression of atherosclerosis.

RECENT FINDINGS

Recent publications have advanced the knowledge in all areas touched by this review: the causal role of lipids in shaping the DNA methylome, the associations between chronic degenerative disease and mitochondrial function, the lipid composition of the atheroma, and the relevance of DNA hypermethylation in atherosclerosis. Evidence is beginning to emerge, linking the dynamics of FA type abundance, mitochondrial function, and DNA methylation in the atheroma and systemically. In particular, this review highlights mitochondrial beta-oxidation as an important regulator of DNA methylation in metabolic disease. Despite the many questions still unanswered, this area of research promises to identify mechanisms and molecular factors that establish a pathological gene expression pattern in atherosclerosis.

Developmental and Transmittable Origins of Obesity-Associated Health Disorders

The current global obesity pandemic is clearly linked to both the increasing prevalence of, and preference for, foods high in calories, specifically fat and sucrose, and declining levels of daily physical activity. A less commonly discussed possible explanation is that risk of obesity begins in utero as a result of developmental plasticity during early life. This idea fits into the broader Developmental Origins of Health and Diseases (DOHAD) hypothesis, which holds that stressful in utero exposure manifests as disease in adulthood. In this review, we highlight several studies that have revealed the role of epigenetics in multigenerational transmission of developmentally programmed obesity and associated cardiometabolic disease.

Differential adipokine DNA methylation and gene expression in subcutaneous adipose tissue from adult offspring of women with diabetes in pregnancy

BACKGROUND

Offspring of women with diabetes in pregnancy are at increased risk of type 2 diabetes mellitus (T2DM), potentially mediated by epigenetic mechanisms. The adipokines leptin, adiponectin, and resistin (genes: LEP, ADIPOQ, RETN) play key roles in the pathophysiology of T2DM. We hypothesized that offspring exposed to maternal diabetes exhibit alterations in epigenetic regulation of subcutaneous adipose tissue (SAT) adipokine transcription. We studied adipokine plasma levels, SAT gene expression, and DNA methylation of LEP, ADIPOQ, and RETN in adult offspring of women with gestational diabetes (O-GDM, N = 82) or type 1 diabetes (O-T1DM, N = 67) in pregnancy, compared to offspring of women from the background population (O-BP, N = 57).

RESULTS

Compared to O-BP, we found elevated plasma leptin and resistin levels in O-T1DM, decreased gene expression of all adipokines in O-GDM, decreased RETN expression in O-T1DM, and increased LEP and ADIPOQ methylation in O-GDM. In multivariate regression analysis, O-GDM remained associated with increased ADIPOQ methylation and decreased ADIPOQ and RETN gene expression and O-T1DM remained associated with decreased RETN expression after adjustment for potential confounders and mediators.

CONCLUSIONS

In conclusion, offspring of women with diabetes in pregnancy exhibit increased ADIPOQ DNA methylation and decreased ADIPOQ and RETN gene expression in SAT. However, altered methylation and expression levels were not reflected in plasma protein levels, and the functional implications of these findings remain uncertain.

Protein-restricted diet during pregnancy after insemination alters behavioral phenotypes of the progeny

Background

Epidemiological studies suggest that hyponutrition during the fetal period increases the risk of mental disorders such as attention deficit hyperactivity disorder and autism-spectrum disorder, which has been experimentally supported using animal models. However, previous experimental hyponutrition or protein-restricted (PR) diets affected stages other than the fetal stage, such as formation of the egg before insemination, milk composition during lactation, and maternal nursing behavior.

Results

We conducted in vitro fertilization and embryo transfer in mice and allowed PR diet and folic acid-supplemented PR diet to affect only fetal environments. Comprehensive phenotyping of PR and control-diet progenies showed moderate differences in fear/anxiety-like, novelty-seeking, and prosocial behaviors, irrespective of folic-acid supplementation. Changes were also detected in gene expression and genomic methylation in the brain.

Conclusions

These results suggest that epigenetic factors in the embryo/fetus influence behavioral and epigenetic phenotypes of progenies. Significant epigenetic alterations in the brains of the progenies induced by the maternal-protein restriction were observed in the present study. To our knowledge, this is first study to evaluate the effect of maternal hyponutrition on behavioral phenotypes using reproductive technology.

Electronic supplementary material

The online version of this article (doi:10.1186/s12263-016-0550-2) contains supplementary material, which is available to authorized users.

Effect of maternal dietary counselling during the 1st year of life on glucose profile and insulin resistance at the age of 8 years: a randomised field trial

Education interventions that stimulate complementary feeding practices can improve the nutritional status of children and may protect against future chronic diseases. We assessed the long-term effectiveness of dietary intervention during the 1st year of life on insulin resistance levels, and investigated the relationship between insulin resistance and weight changes over time. A randomised field trial was conducted among 500 mothers who gave birth to full-term infants between October 2001 and June 2002 in a low-income area in São Leopoldo, Brazil. Mother–child pairs were randomly assigned to intervention (n 200) and control groups (n 300), and the mothers in the intervention group received dietary counselling on breast-feeding and complementary feeding of their children during the 1st year of life. Fieldworkers blinded to assignment assessed socio-demographic, dietary and anthropometric data during follow-up at ages 1, 4 and 8 years. Blood tests were performed in 305 children aged 8 years to measure fasting serum glucose and insulin concentrations and the homoeostasis model assessment index of insulin resistance (HOMA-IR). At the age of 8 years, the intervention group showed no changes in glucose and insulin concentrations or HOMA-IR values (change 0·07; 95 % CI −0·06, 0·21 for girls; and change −0·07; 95 % CI −0·19, 0·04 for boys) compared with study controls. Insulin resistance was highly correlated, however, with increases in BMI between birth and 8 years of age. Although this dietary intervention had no impact on glucose profile at age 8 years, our findings suggest that BMI changes in early childhood can serve as an effective marker of insulin resistance.

Consequences of early adverse rearing experience(EARE) on development: insights from non-human primate studies

Early rearing experiences are important in one's whole life, whereas early adverse rearing experience(EARE) is usually related to various physical and mental disorders in later life. Although there were many studies on human and animals, regarding the effect of EARE on brain development, neuroendocrine systems, as well as the consequential mental disorders and behavioral abnormalities, the underlying mechanisms remain unclear. Due to the close genetic relationship and similarity in social organizations with humans, non-human primate(NHP) studies were performed for over 60 years. Various EARE models were developed to disrupt the early normal interactions between infants and mothers or peers. Those studies provided important insights of EARE induced effects on the physiological and behavioral systems of NHPs across life span, such as social behaviors(including disturbance behavior, social deficiency, sexual behavior, etc), learning and memory ability, brain structural and functional developments(including influences on neurons and glia cells, neuroendocrine systems, e.g., hypothalamic-pituitary-adrenal(HPA) axis, etc). In this review, the effects of EARE and the underlying epigenetic mechanisms were comprehensively summarized and the possibility of rehabilitation was discussed.

Maternal nutrition: opportunities in the prevention of gestational diabetes

Gestational diabetes mellitus (GDM) is currently defined as glucose intolerance that is of variable severity with onset or first recognition during pregnancy. The Hyperglycemia and Adverse Pregnancy Outcome Study, including 25 000 nondiabetic pregnant women in 15 centers across the world, reported that an average of 17.8% of pregnancies are affected by GDM and its frequency can be as high as 25.5% in some countries, based on the International Association of Diabetes and Pregnancy Study Groups criteria. Nevertheless, true global prevalence estimates of GDM are currently lacking due to the high level of heterogeneity in screening approaches, diagnostic criteria, and differences in the characteristics of the populations that were studied. The presence of systemic high blood glucose levels in pregnancy results in an adverse intrauterine environment, which has been shown to have a negative impact on short- and long-term health outcomes for both the mother and her offspring, including increased risks for the infant to develop obesity and for both mother and child to develop type 2 diabetes mellitus later in life. Epigenetic mechanisms that are directly influenced by environmental factors, including nutrition, may play a key role in shaping these future health risks and may be part of this vicious cycle. This article reviews the burden of GDM and the current evidence that supports maternal nutritional interventions as a promising strategy to break the cycle by addressing risk factors associated with GDM.

High sucrose intake during gestation increases angiotensin II type 1 receptor-mediated vascular contractility associated with epigenetic alterations in aged offspring rats

Accruing evidence have confirmed that the fetal programming in response to adverse environmental in utero factors plays essential roles in the pathogenesis of hypertension in later life. High sugar intake has been accepted worldwide in everyday life diet and becomes the critical public health issue. Our previous studies indicated that intake of high sucrose (HS) during pregnancy could change the vascular reactivity and dipsogenic behavior closely associated with abnormal renin-angiotensin system (RAS), to increase the risk of hypertension in adult offspring. In the present study, we tested the hypothesis that maternal HS intake in pregnancy may further deteriorate the Ang II-induced cardiovascular responses in the aged offspring. HS intake was provided to pregnant rats throughout the gestation. Blood pressure (BP) in conscious state and vascular contractility in vitro were measured in 22-month-old aged offspring rats. In addition, mRNA and protein expressions and epigenetic changes of Ang II type 1 receptor (AT₁R) gene in blood vessels were determined with the methods of real-time RT-PCR, Western blotting, and Chromatin Immunoprecipitation Assay (CHIP). Results showed that, in the aged offspring, maternal HS intake during gestation would cause the elevation of basal BP which could be diminished by losartan. Although the circulatory Ang II was not changed, levels of local Ang II were significantly increased in blood vessels. In addition, prenatal HS exposure would significantly enhance the AT₁R-mediated vasoconstrictions in both aorta and mesenteric arteries of the aged offspring. Moreover, in the aged offspring of prenatal HS exposure, mRNA and protein expressions of AT₁R gene in both large and small blood vessels were significantly increased, which should be closely associated with the changes of epigenetic mechanisms such as histone modifications. Collectively, we proposed that maternal HS intake during gestation would cause abnormal BP responses mediated via the enhancement of vascular RAS, together with the increased expression of AT₁R gene related to the its epigenetic changes, which would actually lead to the overt phenotype of hypertension in the aged offspring.