Mother's nutritional miRNA legacy: Nutrition during pregnancy and its possible implications to develop cardiometabolic disease in later life

Interplay between maternal nutrition and epigenetic programming on offspring hypertension

Recent human and animal studies have delineated hypertension can develop in the earliest stage of life. A lack or excess of particular nutrients in the maternal diet may impact the expression of genes associated with BP, leading to an increased risk of hypertension in adulthood. Modulations in gene expression could be caused by epigenetic mechanisms through aberrant DNA methylation, histone modification, and microRNAs (miRNAs). Several molecular mechanisms for the developmental programming of hypertension, including oxidative stress, dysregulated nutrient-sensing signal, aberrant renin-angiotensin system, and dysbiotic gut microbiota have been associated with epigenetic programming. Conversely, maternal nutritional interventions such as amino acids, melatonin, polyphenols, resveratrol or short chain fatty acids may work as epigenetic modifiers to trigger protective epigenetic modifications and prevent offspring hypertension. We present a current perspective of maternal malnutrition that can cause fetal programming and the potential of epigenetic mechanisms lead to offspring hypertension. We also discuss the opportunities of dietary nutrients or nutraceuticals as epigenetic modifiers to counteract those adverse programming actions for hypertension prevention. The extent to which aberrant epigenetic changes can be reprogrammed or reversed by maternal dietary interventions in order to prevent human hypertension remains to be established. Continued research is necessary to evaluate the interaction between maternal malnutrition and epigenetic programming, as well as a greater focus on nutritional interventions for hypertension prevention towards their use in clinical translation.

A comprehensive review on infant formula: nutritional and functional constituents, recent trends in processing and its impact on infants' gut microbiota

Human milk is considered the most valuable form of nutrition for infants for their growth, development and function. So far, there are still some cases where feeding human milk is not feasible. As a result, the market for infant formula is widely increasing, and formula feeding become an alternative or substitute for breastfeeding. The nutritional value of the formula can be improved by adding functional bioactive compounds like probiotics, prebiotics, human milk oligosaccharides, vitamins, minerals, taurine, inositol, osteopontin, lactoferrin, gangliosides, carnitine etc. For processing of infant formula, diverse thermal and non-thermal technologies have been employed. Infant formula can be either in powdered form, which requires reconstitution with water or in ready-to-feed liquid form, among which powder form is readily available, shelf-stable and vastly marketed. Infants' gut microbiota is a complex ecosystem and the nutrient composition of infant formula is recognized to have a lasting effect on it. Likewise, the gut microbiota establishment closely parallels with host immune development and growth. Therefore, it must be contemplated as an important factor for consideration while developing formulas. In this review, we have focused on the formulation and manufacturing of safe and nutritious infant formula equivalent to human milk or aligning with the infant's needs and its ultimate impact on infants' gut microbiota.

miR-24-3p and Body Mass Index as Type 2 Diabetes Risk Factors in Spanish Women 15 Years after Gestational Diabetes Mellitus Diagnosis

Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance that is diagnosed for the first time during pregnancy. The objective of this study is to know the glucose tolerance status after 15 years of pregnancy in patients diagnosed with gestational diabetes and to assess the long-term effect of GDM on the circulating miRNA profile of these women. To answer these, 30 randomly selected women diagnosed with GDM during 2005-2006 were included in the study, and glucose tolerance was measured using the National Diabetes Data Group criteria. Additionally, four miRNAs (hsa-miR-1-3p, hsa-miR-24-3p, hsa-miR-329-3p, hsa-miR-543) were selected for their analysis in the plasma of women 15 years after the diagnosis of GDM. In our study we discovered that, fifteen years after the diagnosis of GDM, 50% of women have some degree of glucose intolerance directly related to body weight and body mass index during pregnancy. Dysglycemic women also showed a significantly increased level of circulating hsa-miR-24-3p. Thus, we can conclude that initial weight and BMI, together with circulating expression levels of hsa-miR-24-3p, could be good predictors of the future development of dysglycemia in women with a previous diagnosis of GDM.

Cow's milk may be delivering potentially harmful undetected cargoes to humans. Is it time to reconsider dairy recommendations?

Mammalian evolution has shaped milk into a species-specific vehicle for post-natal development, continuing what began within the mother's womb. Increased consumption of the mother's breast milk is associated with the most adequate metabolic programming and lowers the incidence of the diseases of civilization during adulthood. An abundance of short sequences of RNA, known as microRNA, exists in mammalian breast milk, enclosed within robust small extracellular vesicles known as exosomes. These microRNAs can epigenetically regulate over 60% of human genes. When cow's milk is consumed by humans, the bovine exosomes are transported through the gastrointestinal tract, detected intact in the blood stream, and taken up by target cells, where they alter protein expression. The aim of this review was to highlight the role of dairy exosomes and microRNA, and of the type of dairy product consumed, in human diseases. Given that microRNAs are involved in a vast array of physiological processes and associated with several diseases, perhaps caution should be practiced with regard to human consumption of dairy, particularly for individuals within developmentally critical time frames, such as pregnant and lactating mothers, and young children.

Peroxisome Proliferator-Activated Receptors (PPAR), fatty acids and microRNAs: Implications in women delivering low birth weight babies

Low birth weight (LBW) babies are associated with neonatal morbidity and mortality and are at increased risk for noncommunicable diseases (NCDs) in later life. However, the molecular determinants of LBW are not well understood. Placental insufficiency/dysfunction is the most frequent etiology for fetal growth restriction resulting in LBW and placental epigenetic processes are suggested to be important regulators of pregnancy outcome. Early life exposures like altered maternal nutrition may have long-lasting effects on the health of the offspring via epigenetic mechanisms like DNA methylation and microRNA (miRNA) regulation. miRNAs have been recognized as major regulators of gene expression and are known to play an important role in placental development. Angiogenesis in the placenta is known to be regulated by transcription factor peroxisome proliferator-activated receptor (PPAR) which is activated by ligands such as long-chain-polyunsaturated fatty acids (LCPUFA). In vitro studies in different cell types indicate that fatty acids can influence epigenetic mechanisms like miRNA regulation. We hypothesize that maternal fatty acid status may influence the miRNA regulation of PPAR genes in the placenta in women delivering LBW babies. This review provides an overview of miRNAs and their regulation of PPAR gene in the placenta of women delivering LBW babies.Abbreviations: AA - Arachidonic Acid; Ago2 - Argonaute2; ALA - Alpha-Linolenic Acid; ANGPTL4 - Angiopoietin-Like Protein 4; C14MC - Chromosome 14 miRNA Cluster; C19MC - Chromosome 19 miRNA Cluster; CLA - Conjugated Linoleic Acid; CSE - Cystathionine γ-Lyase; DHA - Docosahexaenoic Acid; EFA - Essential Fatty Acids; E2F3 - E2F transcription factor 3; EPA - Eicosapentaenoic Acid; FGFR1 - Fibroblast Growth Factor Receptor 1; GDM - Gestational Diabetes Mellitus; hADMSCs - Human Adipose Tissue-Derived Mesenchymal Stem Cells; hBMSCs - Human Bone Marrow Mesenchymal Stem Cells; HBV - Hepatitis B Virus; HCC - Hepatocellular Carcinoma; HCPT - Hydroxycamptothecin; HFD - High-Fat Diet; Hmads - Human Multipotent Adipose-Derived Stem; HSCS - Human Hepatic Stellate Cells; IUGR - Intrauterine Growth Restriction; LA - Linoleic Acid; LBW - Low Birth Weight; LCPUFA - Long-Chain Polyunsaturated Fatty Acids; MEK1 - Mitogen-Activated Protein Kinase 1; MiRNA - MicroRNA; mTOR - Mammalian Target of Rapamycin; NCDs - NonCommunicable Diseases; OA - Oleic Acid; PASMC - Pulmonary Artery Smooth Muscle Cell; PLAG1 - Pleiomorphic Adenoma Gene 1; PPAR - Peroxisome Proliferator-Activated Receptor; PPARα - PPAR alpha; PPARγ - PPAR gamma; PPARδ - PPAR delta; pre-miRNA - precursor miRNA; RISC - RNA-Induced Silencing Complex; ROS - Reactive Oxygen Species; SAT - Subcutaneous Adipose Tissue; WHO - World Health Organization.

Postprandial Circulating miRNAs in Response to a Dietary Fat Challenge

Postprandial lipemia has many physiopathological effects, some of which increase the risk of cardiovascular disease. MicroRNAs (miRNAs) can be found in almost all biological fluids, but their postprandial kinetics are poorly described. We aimed to profile circulating miRNAs in response to a fat challenge. In total, 641 circulating miRNAs were assessed by real-time PCR in plasmas from mice two hours after lipid gavage. Mice with intestine-specific loss of Dicer were screened to identify potential miRNAs released by the intestine. A total of 68 miRNAs were selected for further validation. Ten circulating miRNAs were finally validated as responsive to postprandial lipemia, including miR-206-3p, miR-543-3p, miR-466c-5p, miR-27b-5p, miR-409-3p, miR-340-3p, miR-1941-3p, miR-10a-3p, miR-125a-3p, and miR-468-3p. Analysis of their possible tissues of origin/target showed an enrichment of selected miRNAs in liver, intestine, brain, or skeletal muscle. miR-206, miR-27b-5p, and miR-409-3p were validated in healthy humans. Analysis of their predicted target genes revealed their potential involvement in insulin/insulin like growth factor (insulin/IGF), angiogenesis, cholecystokinin B receptor signaling pathway (CCKR), inflammation or Wnt pathways for mice, and in platelet derived growth factor (PDGF) and CCKR signaling pathways for humans. Therefore, the current study shows that certain miRNAs are released in the circulation in response to fatty meals, proposing them as potential novel therapeutic targets of lipid metabolism.

Plant MIR156 regulates intestinal growth in mammals by targeting the Wnt/β-catenin pathway

MicroRNAs (miRNAs) are important negative regulators of genes involved in physiological and pathological processes in plants and animals. Recent studies have shown that miRNAs might regulate gene expression among different species in a cross-kingdom manner. However, the specific roles of plant miRNAs in animals remain poorly understood and somewhat. Herein, we found that plant MIR156 regulates proliferation of intestinal cells both in vitro and in vivo. Continuous administration of a high plant miRNA diet or synthetic MIR156 elevated MIR156 levels and inhibited the Wnt/β-catenin signaling pathway in mouse intestine. Bioinformatics predictions and luciferase reporter assays indicated that MIR156 targets Wnt10b. In vitro, MIR156 suppressed proliferation by downregulating the Wnt10b protein and upregulating β-catenin phosphorylation in the porcine jejunum epithelial (IPEC-J2) cell line. Lithium chloride and an MIR156 inhibitor relieved this inhibition. This research is the first to demonstrate that plant MIR156 inhibits intestinal cell proliferation by targeting Wnt10b. More importantly, plant miRNAs may represent a new class of bioactive molecules that act as epigenetic regulators in humans and other animals.

Advances in Infant Formula Science

Human milk contains a plethora of nutrients and bioactive components to help nourish the developing neonate and is considered the “gold standard” for early life nutrition—as befits the only food “designed” by evolution to feed human infants. Over the past decade, there is considerable evidence that highlights the “intelligence” contained in milk components that contribute to infant health beyond basic nutrition—in areas such as programming the developing microbiome and immune system and protecting against infection. Such discoveries have led to new opportunities for infant milk formula (IMF) manufacturers to refine nutritional content in order to simulate the functionality of breast milk. These include the addition of specialized protein fractions as well as fatty acid and complex carbohydrate components—all of which have mechanistic supporting evidence in terms of improving the health and nutrition of the infant. Moreover, IMF is the single most important dietary intervention whereby the human microbiome can be influenced at a crucial early stage of development. In this respect, it is expected that the complexity of IMF will continue to increase as we get a greater understanding of how it can modulate microbiota development (including the development of probiotics, prebiotics, and synbiotics) and influence long-term health. This review provides a scientific evaluation of key features of importance to infant nutrition, including differences in milk composition and emerging “humanized” ingredients.

Effects of oral implants with miR‑122‑modified cell sheets on rat bone marrow mesenchymal stem cells

The aim of the present study was to regulate the transformation of bone marrow mesenchymal stem cells (BMMSCs) to osteoblasts to promote bone formation and osseointegration surrounding oral implants. BMMSCs were cultured using the whole bone marrow adherence method. Cell surface markers were detected by flow cytometry, and multi‑lineage differentiation potential was detected by osteogenic and adipogenic tests. miR‑122‑modified cell sheets were prepared by non‑viral transfection and complexed with micro‑arc titanium oxide implants to construct a gene‑modified tissue‑engineered implant, with its surface morphology observed by scanning electron microscopy (SEM). In vitro osteogenic activity of the implant was determined by alkaline phosphatase (ALP), Sirius Red, alizarin red staining, polymerase chain reaction and western blot analysis. The BMMSCs were spindle‑ or triangular‑shaped. Surface markers, cluster of differentiation 29 (CD29), CD90 and CD105 were positively expressed, whereas blood cell markers CD34, CD45 and CD31 were negatively expressed. Osteogenic staining exhibited deposition of calcified nodules, while adipogenic staining demonstrated the formation of lipid droplets. miR‑122 modification significantly enhanced the in vitro osteogenic activity of the sheets. On day 3 of osteogenic induction, runt-related transcription factor 2, osterix, osteocalcin, collagen I, ALP and bone morphogenetic protein 2 expression levels of the experimental group were 2.0, 3.1, 4.6, 3.2, 10.5 and 4.5 times those of the blank control group, respectively. SEM imaging of the modified sheet demonstrated close adhesion and fitting between abundant cellular and extracellular matrices, and the porous surface of the implant. In vitro osteogenesis of the complex was promoted and accelerated. Thus, miR‑122 effectively promoted osteogenic differentiation of the BMMSC sheet. Therefore, it is feasible to construct gene‑modified tissue‑engineered implants by complexing miR‑122‑modified sheets with micro‑arc titanium oxide implants.

Primary Pediatric Hypertension: Current Understanding and Emerging Concepts

The rising prevalence of primary pediatric hypertension and its tracking into adult hypertension point to the importance of determining its pathogenesis to gain insights into its current and emerging management. Considering that the intricate control of BP is governed by a myriad of anatomical, molecular biological, biochemical, and physiological systems, multiple genes are likely to influence an individual's BP and susceptibility to develop hypertension. The long-term regulation of BP rests on renal and non-renal mechanisms. One renal mechanism relates to sodium transport. The impaired renal sodium handling in primary hypertension and salt sensitivity may be caused by aberrant counter-regulatory natriuretic and anti-natriuretic pathways. The sympathetic nervous and renin-angiotensin-aldosterone systems are examples of antinatriuretic pathways. An important counter-regulatory natriuretic pathway is afforded by the renal autocrine/paracrine dopamine system, aberrations of which are involved in the pathogenesis of hypertension, including that associated with obesity. We present updates on the complex interactions of these two systems with dietary salt intake in relation to obesity, insulin resistance, inflammation, and oxidative stress. We review how insults during pregnancy such as maternal and paternal malnutrition, glucocorticoid exposure, infection, placental insufficiency, and treatments during the neonatal period have long-lasting effects in the regulation of renal function and BP. Moreover, these effects have sex differences. There is a need for early diagnosis, frequent monitoring, and timely management due to increasing evidence of premature target organ damage. Large controlled studies are needed to evaluate the long-term consequences of the treatment of elevated BP during childhood, especially to establish the validity of the current definition and treatment of pediatric hypertension.

Treating the placenta to prevent adverse effects of gestational hypoxia on fetal brain development

Some neuropsychiatric disease, including schizophrenia, may originate during prenatal development, following periods of gestational hypoxia and placental oxidative stress. Here we investigated if gestational hypoxia promotes damaging secretions from the placenta that affect fetal development and whether a mitochondria-targeted antioxidant MitoQ might prevent this. Gestational hypoxia caused low birth-weight and changes in young adult offspring brain, mimicking those in human neuropsychiatric disease. Exposure of cultured neurons to fetal plasma or to secretions from the placenta or from model trophoblast barriers that had been exposed to altered oxygenation caused similar morphological changes. The secretions and plasma contained altered microRNAs whose targets were linked with changes in gene expression in the fetal brain and with human schizophrenia loci. Molecular and morphological changes in vivo and in vitro were prevented by a single dose of MitoQ bound to nanoparticles, which were shown to localise and prevent oxidative stress in the placenta but not in the fetus. We suggest the possibility of developing preventative treatments that target the placenta and not the fetus to reduce risk of psychiatric disease in later life.

Nutrition, microRNAs, and Human Health

MicroRNAs (miRs) hybridize with complementary sequences in mRNA and silence genes by destabilizing mRNA or preventing translation of mRNA. Over 60% of human protein-coding genes are regulated by miRs, and 1881 high-confidence miRs are encoded in the human genome. Evidence suggests that miRs not only are synthesized endogenously, but also might be obtained from dietary sources, and that food compounds alter the expression of endogenous miR genes. The main food matrices for studies of biological activity of dietary miRs include plant foods and cow milk. Encapsulation of miRs in exosomes and exosome-like particles confers protection against RNA degradation and creates a pathway for intestinal and vascular endothelial transport by endocytosis, as well as delivery to peripheral tissues. Evidence suggests that the amount of miRs absorbed from nutritionally relevant quantities of foods is sufficient to elicit biological effects, and that endogenous synthesis of miRs is insufficient to compensate for dietary miR depletion and rescue wild-type phenotypes. In addition, nutrition alters the expression of endogenous miR genes, thereby compounding the effects of nutrition-miR interactions in gene regulation and disease diagnosis in liquid biopsies. For example, food components and dietary preferences may modulate serum miR profiles that may influence biological processes. The complex crosstalk between nutrition, miRs, and gene targets poses a challenge to gene network analysis and studies of human disease. Novel pipelines and databases have been developed recently, including a dietary miR database for archiving reported miRs in 15 dietary resources. miRs derived from diet and endogenous synthesis have been implicated in physiologic and pathologic conditions, including those linked with nutrition and metabolism. In fact, several miRs are actively regulated in response to overnutrition and tissue inflammation, and are involved in facilitating the development of chronic inflammation by modulating tissue-infiltrated immune cell function.

Maternal high-calorie diet is associated with altered hepatic microRNA expression and impaired metabolic health in offspring at weaning age

High-calorie diet (HCD) feeding in mice predisposes offspring for impaired glucose homeostasis and obesity. However, the mechanisms underlying these detrimental effects of maternal nutrition, especially during early life of offspring, are incompletely understood. MicroRNAs (miRNAs) are small non-coding RNAs that can regulate target gene expression. Here we hypothesized that impaired metabolic health in offspring from HCD-fed dams at weaning is associated with dysregulated expression of hepatic miRNAs. Dams were fed a chow diet (CD; 11.4 % kcal fat, 62.8 % from carbohydrate, 25.8 % from protein) or HCD (58 % kcal from fat; 25.6 % from carbohydrate, 16.4 % from protein) during gestation and lactation, and metabolic health was assessed in male offspring at weaning. Hepatic levels of miRNAs and target genes were investigated in offspring from CD- or HCD-fed dams using gene and protein expression. Maternal HCD feeding impaired metabolic health in offspring compared to offspring from CD-fed dams. Microarray analysis indicated that expressions of miR-615-5p, miR-3079-5p, miR-124*, and miR-101b* were downregulated, whereas miR-143* was upregulated, in livers from offspring from HCD-fed dams. Our functional enrichment analysis indicated that the target genes of these differentially expressed miRNAs, including tumor necrosis factor-α (TNF-α) and mitogen-activated protein kinase 1 (MAPK1), were mapped to inflammatory pathways. Finally, we verified that both mRNA and protein levels of the pro-inflammatory modulators TNF-α and MAPK1 were significantly increased in livers of offspring from HCD-fed dams at weaning. Maternal HCD feeding predisposes offspring to a higher body weight and impaired glucose metabolism at weaning. To the best of knowledge, our study is the first to show that maternal HCD consumption impairs metabolic health, modulates hepatic miRNA expression, and increases markers of hepatic inflammation in offspring as early as at weaning age.

Does intrauterine exposure to hypercholesterolemia adversely affect familial hypercholesterolemia phenotype?

PURPOSE OF REVIEW

There is currently limited information as to whether maternally or paternally inherited familial hypercholesterolemia confers different phenotype risk to offspring. Knowledge about the differences in risk conferred by inheritance could be important with respect to follow-up and more individually targeted treatment of subjects with familial hypercholesterolemia.

RECENT FINDINGS

Few studies have, with inconsistent results so far, investigated the significance of familial hypercholesterolemia inheritance on cardiovascular risk markers in offspring. Maternal inheritance of familial hypercholesterolemia includes hypercholesterolemic in-utero conditions for the offspring. How this may influence later risk is briefly discussed in the article.

SUMMARY

Current data suggest that the dominating factor of the familial hypercholesterolemia (FH) phenotype is the mutation and not the inheritance, however, maternal inheritance of FH has been reported to adversely affect FH phenotype in terms of increased mortality. More knowledge about how intrauterine hypercholesterolemia during pregnancy influences epigenetic modifications and later cardiovascular disease risk in offspring is needed and this may open up new avenues of treatment of pregnant women with familial hypercholesterolemia.

Developmental programming: State-of-the-science and future directions-Summary from a Pennington Biomedical symposium

OBJECTIVE

On December 8-9, 2014, the Pennington Biomedical Research Center convened a scientific symposium to review the state-of-the-science and future directions for the study of developmental programming of obesity and chronic disease. The objectives of the symposium were to discuss: (i) past and current scientific advances in animal models, population-based cohort studies, and human clinical trials, (ii) the state-of-the-science of epigenetic-based research, and (iii) considerations for future studies.

RESULTS

This symposium provided a comprehensive assessment of the state of the scientific field and identified research gaps and opportunities for future research in order to understand the mechanisms contributing to the developmental programming of health and disease.

CONCLUSIONS

Identifying the mechanisms which cause or contribute to developmental programming of future generations will be invaluable to the scientific and medical community. The ability to intervene during critical periods of prenatal and early postnatal life to promote lifelong health is the ultimate goal. Considerations for future research including the use of animal models, the study design in human cohorts with considerations about the timing of the intrauterine exposure, and the resulting tissue-specific epigenetic signature were extensively discussed and are presented in this meeting summary.

In Utero Origins of Hypertension: Mechanisms and Targets for Therapy

The developmental origins of health and disease theory is based on evidence that a suboptimal environment during fetal and neonatal development can significantly impact the evolution of adult-onset disease. Abundant evidence exists that a compromised prenatal (and early postnatal) environment leads to an increased risk of hypertension later in life. Hypertension is a silent, chronic, and progressive disease defined by elevated blood pressure (>140/90 mmHg) and is strongly correlated with cardiovascular morbidity/mortality. The pathophysiological mechanisms, however, are complex and poorly understood, and hypertension continues to be one of the most resilient health problems in modern society. Research into the programming of hypertension has proposed pharmacological treatment strategies to reverse and/or prevent disease. In addition, modifications to the lifestyle of pregnant women might impart far-reaching benefits to the health of their children. As more information is discovered, more successful management of hypertension can be expected to follow; however, while pregnancy complications such as fetal growth restriction, preeclampsia, preterm birth, etc., continue to occur, their offspring will be at increased risk for hypertension. This article reviews the current knowledge surrounding the developmental origins of hypertension, with a focus on mechanistic pathways and targets for therapeutic and pharmacologic interventions.