Maternal obesity increases hypothalamic miR-505-5p expression in mouse offspring leading to altered fatty acid sensing and increased intake of high-fat food.

In utero exposure to maternal obesity programs increased obesity risk. Animal models show that programmed offspring obesity is preceded by hyperphagia, but the mechanisms that mediate these changes are unknown. Using a mouse model of maternal obesity, we observed increased intake of a high-fat diet (HFD) in offspring of obese mothers that precedes the development of obesity. Through small RNA sequencing, we identified programmed overexpression of hypothalamic miR-505-5p that is established in the fetus, lasts to adulthood and is maintained in hypothalamic neural progenitor cells cultured in vitro. Metabolic hormones and long-chain fatty acids associated with obesity increase miR-505-5p expression in hypothalamic neurons in vitro. We demonstrate that targets of miR-505-5p are enriched in fatty acid metabolism pathways and overexpression of miR-505-5p decreased neuronal fatty acid metabolism in vitro. miR-505-5p targets are associated with increased BMI in human genetic studies. Intra-cerebroventricular injection of miR-505-5p in wild-type mice increased HFD intake, mimicking the phenotype observed in offspring exposed to maternal obesity. Conversely, maternal exercise intervention in an obese mouse pregnancy rescued the programmed increase of hypothalamic miR-505-5p in offspring of obese dams and reduced HFD intake to control offspring levels. This study identifies a novel mechanism by which maternal obesity programs obesity in offspring via increased intake of high-fat foods.

Vernix caseosa reveals mechanistic clues linking maternal obesity to atopic dermatitis pathogenesis.

BACKGROUND: Maternal overweight and obesity have been associated with an increased risk of atopic dermatitis (AD) in the offspring, but the underlying mechanisms are unclear. Vernix caseosa (VC) is a proteolipid material covering the fetus produced during skin development. However, whether maternal prepregnancy weight excess influences fetal skin development is unknown. Characterizing the VC of newborns from mothers with prepregnancy overweight and obesity might reveal AD-prone alterations during fetal skin development. OBJECTIVE: We sought to explore AD biomarkers and staphylococcal loads in VC from the offspring of mothers who were overweight/obese (O/O) before pregnancy versus in those from offspring of normal weight mothers. METHODS: The VC of newborns of 14 O/O and 12 normal weight mothers were collected immediately after birth. Biomarkers were determined by ELISA and staphylococcal species by quantitative PCR. RESULTS: The VC from the O/O group showed decreased expression of skin barrier proteins (filaggrin and loricrin) and increased levels of proinflammatory biomarkers (IgA, thymic stromal lymphopoietin [TSLP], S100A8, IL-25, and IL-33). No differences in concentrations of antimicrobial peptides and enzymes were detected. The VC from the O/O group had a lower Staphylococcus epidermidis and Staphylococcus hominis commensal bacterial load, whereas Staphylococcus aureus bacterial load was not significantly different between the 2 groups. Maternal body mass index was negatively correlated with VC filaggrin expression and S epidermidis load and was positively associated with TSLP concentration. One-year follow-up established that the offspring of O/O mothers had a higher incidence of AD that was specifically linked with decreased VC filaggrin expression and lower S epidermidis load. CONCLUSIONS: VC from neonates of mothers with prepregnancy overweight and obesity exhibit skin barrier molecular alterations and staphylococcal dysbiosis that suggest early mechanistic clues to this population's increased risk of AD.

Parental obesity predisposes offspring to kidney dysfunction and increased susceptibility to ischemia-reperfusion injury in a sex-dependent manner.

Although obesity is recognized as a risk factor for cardiorenal and metabolic diseases, the impact of parental obesity on the susceptibility of their offspring to renal injury at adulthood is unknown. We examined the impact of parental obesity on offspring kidney function, morphology, and markers of kidney damage after acute kidney injury (AKI). Offspring from normal (N) diet-fed C57BL/6J parents were fed either N (NN) or a high-fat (H) diet (NH) from weaning until adulthood. Offspring from obese H diet-fed parents were fed N (HN) or H diet (HH) after weaning. All offspring groups were submitted to bilateral AKI by clamping the left and right renal pedicles for 30 min. Compared with male NH and NN offspring from lean parents, male HH and HN offspring from obese parents exhibited higher kidney injury markers such as urinary, renal osteopontin, plasma creatinine, urinary albumin excretion, and neutrophil gelatinase-associated lipocalin (NGAL) levels, and worse histological injury score at 22 wk of age. Only albumin excretion and NGAL were elevated in female HH offspring from obese parents compared with lean and obese offspring from lean parents. We also found an increased mortality rate and worse kidney injury scores after AKI in male offspring from obese parents, regardless of the diet consumed after weaning. Female offspring were protected from major kidney injury after AKI. These results indicate that parental obesity leads to increased kidney injury in their offspring after ischemia-reperfusion in a sex-dependent manner, even when their offspring remain lean.NEW & NOTEWORTHY Offspring from obese parents are more susceptible to kidney injury and worse outcomes following an acute ischemia-reperfusion insult. Male, but not female, offspring from obese parents exhibit increased blood pressure early in life. Female offspring are partially protected against major kidney injury induced by ischemia-reperfusion.

Long-term impact of maternal obesity on the gliovascular unit and ephrin signaling in the hippocampus of adult offspring.

BACKGROUND: Children born to obese mothers are at increased risk of developing mood disorders and cognitive impairment. Experimental studies have reported structural changes in the brain such as the gliovascular unit as well as activation of neuroinflammatory cells as a part of neuroinflammation processing in aged offspring of obese mothers. However, the molecular mechanisms linking maternal obesity to poor neurodevelopmental outcomes are not well established. The ephrin system plays a major role in a variety of cellular processes including cell-cell interaction, synaptic plasticity, and long-term potentiation. Therefore, in this study we determined the impact of maternal obesity in pregnancy on cortical, hippocampal development, vasculature and ephrin-A3/EphA4-signaling, in the adult offspring in mice. METHODS: Maternal obesity was induced in mice by a high fat/high sugar Western type of diet (HF/HS). We collected brain tissue (prefrontal cortex and hippocampus) from 6-month-old offspring of obese and lean (control) dams. Hippocampal volume, cortical thickness, myelination of white matter, density of astrocytes and microglia in relation to their activity were analyzed using 3-D stereological quantification. mRNA expression of ephrin-A3, EphA4 and synaptic markers were measured by qPCR in the brain tissue. Moreover, expression of gap junction protein connexin-43, lipocalin-2, and vascular CD31/Aquaporin 4 were determined in the hippocampus by immunohistochemistry. RESULTS: Volume of hippocampus and cortical thickness were significantly smaller, and myelination impaired, while mRNA levels of hippocampal EphA4 and post-synaptic density (PSD) 95 were significantly lower in the hippocampus in the offspring of obese dams as compared to offspring of controls. Further analysis of the hippocampal gliovascular unit indicated higher coverage of capillaries by astrocytic end-feet, expression of connexin-43 and lipocalin-2 in endothelial cells in the offspring of obese dams. In addition, offspring of obese dams demonstrated activation of microglia together with higher density of cells, while astrocyte cell density was lower. CONCLUSION: Maternal obesity affects brain size, impairs myelination, disrupts the hippocampal gliovascular unit and decreases the mRNA expression of EphA4 and PSD-95 in the hippocampus of adult offspring. These results indicate that the vasculature-glia cross-talk may be an important mediator of altered synaptic plasticity, which could be a link between maternal obesity and neurodevelopmental/neuropsychiatric disorders in the offspring.

Cannabidiol improves maternal obesity-induced behavioral, neuroinflammatory and neurochemical dysfunctions in the juvenile offspring.

Maternal obesity is associated with an increased risk of psychiatric disorders such as anxiety, depression, schizophrenia and autism spectrum disorder in the offspring. While numerous studies focus on preventive measures targeting the mothers, only a limited number provide practical approaches for addressing the damages once they are already established. We have recently demonstrated the interplay between maternal obesity and treatment with cannabidiol (CBD) on hypothalamic inflammation and metabolic disturbances, however, little is known about this relationship on behavioral manifestations and neurochemical imbalances in other brain regions. Therefore, here we tested whether CBD treatment could mitigate anxiety-like and social behavioral alterations, as well as neurochemical disruptions in both male and female offspring of obese dams. Female Wistar rats were fed a cafeteria diet for 12 weeks prior to mating, and during gestation and lactation. Offspring received CBD (50 mg/kg) from weaning for 3 weeks. Behavioral tests assessed anxiety-like manifestations and social behavior, while neuroinflammatory and neurochemical markers were evaluated in the prefrontal cortex (PFC) and hippocampus. CBD treatment attenuated maternal obesity-induced anxiety-like and social behavioral alterations, followed by rescuing effects on imbalanced neurotransmitter and endocannabinoid concentrations and altered expression of glial markers, CB1, oxytocin and dopamine receptors, with important differences between sexes. Overall, the findings of this study provide insight into the signaling pathways for the therapeutic benefits of CBD on neuroinflammation and neurochemical imbalances caused by perinatal maternal obesity in the PFC and the hippocampus, which translates into the behavioral manifestations, highlighting the sexual dimorphism encompassing both the transgenerational effect of obesity and the endocannabinoid system.

Maternal obesity and placental function: impaired maternal-fetal axis.

The prevalence of maternal obesity rapidly increases, which represents a major public health concern worldwide. Maternal obesity is characteristic by metabolic dysfunction and chronic inflammation. It is associated with health problems in both mother and offspring. Increasing evidence indicates that the placenta is an axis connecting maternal obesity with poor outcomes in the offspring. In this brief review, we have summarized the current data regarding deregulated placental function in maternal obesity. The data show that maternal obesity induces numerous placental defects, including lipid and glucose metabolism, stress response, inflammation, immune regulation and epigenetics. These placental defects affect each other and result in a stressful intrauterine environment, which transduces and mediates the adverse effects of maternal obesity to the fetus. Further investigations are required to explore the exact molecular alterations in the placenta in maternal obesity, which may pave the way to develop specific interventions for preventing epigenetic and metabolic programming in the fetus.

Preconception Diet Interventions in Obese Outbred Mice and the Impact on Female Offspring Metabolic Health and Oocyte Quality.

Obese individuals often suffer from metabolic health disorders and reduced oocyte quality. Preconception diet interventions in obese outbred mice restore metabolic health and oocyte quality and mitochondrial ultrastructure. Also, studies in inbred mice have shown that maternal obesity induces metabolic alterations and reduces oocyte quality in offspring (F1). Until now, the effect of maternal high-fat diet on F1 metabolic health and oocyte quality and the potential beneficial effects of preconception dietary interventions have not been studied together in outbred mice. Therefore, we fed female mice a high-fat/high-sugar (HF/HS) diet for 7 weeks and switched them to a control (CONT) or caloric-restriction (CR) diet or maintained them on the HF/HS diet for 4 weeks before mating, resulting in three treatment groups: diet normalization (DN), CR, and HF/HS. In the fourth group, mice were fed CONT diet for 11 weeks (CONT). HF/HS mice were fed an HF/HS diet from conception until weaning, while all other groups were then fed a CONT diet. After weaning, offspring were kept on chow diet and sacrificed at 11 weeks. We observed significantly elevated serum insulin concentrations in female HF/HS offspring and a slightly increased percentage of mitochondrial ultrastructural abnormalities, mitochondrial size, and mitochondrial mean gray intensity in HF/HS F1 oocytes. Also, global DNA methylation was increased and cellular stress-related proteins were downregulated in HF/HS F1 oocytes. Mostly, these alterations were prevented in the DN group, while, in CR, this was only the case for a few parameters. In conclusion, this research has demonstrated for the first time that a maternal high-fat diet in outbred mice has a moderate impact on female F1 metabolic health and oocyte quality and that preconception DN is a better strategy to alleviate this compared to CR.

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women.

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.

Maternal obesity damages the median eminence blood-brain barrier structure and function in the progeny: the beneficial impact of cross-fostering by lean mothers.

Maternal obesity is an important risk factor for obesity, cardiovascular, and metabolic diseases in the offspring. Studies have shown that it leads to hypothalamic inflammation in the progeny, affecting the function of neurons regulating food intake and energy expenditure. In adult mice fed a high-fat diet, one of the hypothalamic abnormalities that contribute to the development of obesity is the damage of the blood-brain barrier (BBB) at the median eminence-arcuate nucleus (ME-ARC) interface; however, how the hypothalamic BBB is affected in the offspring of obese mothers requires further investigation. Here, we used confocal and transmission electron microscopy, transcript expression analysis, glucose tolerance testing, and a cross-fostering intervention to determine the impact of maternal obesity and breastfeeding on BBB integrity at the ME-ARC interface. The offspring of obese mothers were born smaller; conversely, at weaning, they presented larger body mass and glucose intolerance. In addition, maternal obesity-induced structural and functional damage of the offspring's ME-ARC BBB. By a cross-fostering intervention, some of the defects in barrier integrity and metabolism seen during development in an obesogenic diet were recovered. The offspring of obese dams breastfed by lean dams presented a reduction of body mass and glucose intolerance as compared to the offspring continuously exposed to an obesogenic environment during intrauterine and perinatal life; this was accompanied by partial recovery of the anatomical structure of the ME-ARC interface, and by the normalization of transcript expression of genes coding for hypothalamic neurotransmitters involved in energy balance and BBB integrity. Thus, maternal obesity promotes structural and functional damage of the hypothalamic BBB, which is, in part, reverted by lactation by lean mothers.NEW & NOTEWORTHY Maternal dietary habits directly influence offspring health. In this study, we aimed at determining the impact of maternal obesity on BBB integrity. We show that DIO offspring presented a leakier ME-BBB, accompanied by changes in the expression of transcripts encoding for endothelial and tanycytic proteins, as well as of hypothalamic neuropeptides. Breastfeeding in lean dams was sufficient to protect the offspring from ME-BBB disruption, providing a preventive strategy of nutritional intervention during early life.

Obesity in pregnancy-Long-term effects on offspring hypothalamic-pituitary-adrenal axis and associations with placental cortisol metabolism: A systematic review.

Obesity, affecting one in three pregnant women worldwide, is not only a major obstetric risk factor. The resulting low-grade inflammation may have a long-term impact on the offspring's HPA axis through dysregulation of maternal, placental and fetal corticosteroid metabolism, and children born of obese mothers have increased risk of diabetes and cardiovascular disease. The long-term effects of maternal obesity on offspring neurodevelopment are, however, undetermined and could depend on the specific effects on placental and fetal cortisol metabolism. This systematic review evaluates how maternal obesity affects placental cortisol metabolism and the offspring's HPA axis. Pubmed, Embase and Scopus were searched for original studies on maternal BMI, obesity, and cortisol metabolism and transfer. Fifteen studies were included after the screening of 4556 identified records. Studies were small with heterogeneous exposures and outcomes. Two studies found that maternal obesity reduced placental HSD11ß2 activity. In one study, umbilical cord blood cortisol levels were affected by maternal BMI. In three studies, an altered cortisol response was consistently seen among offspring in childhood (n = 2) or adulthood (n = 1). Maternal BMI was not associated with placental HSD11ß1 or HSD11ß2 mRNA expression, or placental HSD11ß2 methylation. In conclusion, high maternal BMI is associated with reduced placental HSD11ß2 activity and a dampened cortisol level among offspring, but the data is sparse. Further investigations are needed to clarify whether the HPA axis is affected by prenatal factors including maternal obesity and investigate if adverse effects can be ameliorated by optimising the intrauterine environment.

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

BACKGROUND: It is now understood that it is the quality rather than the absolute amount of adipose tissue that confers risk for obesity-associated disease. Adipose-derived stem cells give rise to adipocytes during the developmental establishment of adipose depots. In adult depots, a reservoir of progenitors serves to replace adipocytes that have reached their lifespan and for recruitment to increase lipid buffering capacity under conditions of positive energy balance. MAIN: The adipose tissue expandability hypothesis posits that a failure in de novo differentiation of adipocytes limits lipid storage capacity and leads to spillover of lipids into the circulation, precipitating the onset of obesity-associated disease. Since adipose progenitors are specified to their fate during late fetal life, perturbations in the intrauterine environment may influence the rapid expansion of adipose depots that occurs in childhood or progenitor function in established adult depots. Neonates born to mothers with obesity or diabetes during pregnancy tend to have excessive adiposity at birth and are at increased risk for childhood adiposity and cardiometabolic disease. CONCLUSION: In this narrative review, we synthesize current knowledge in the fields of obesity and developmental biology together with literature from the field of the developmental origins of health and disease (DOHaD) to put forth the hypothesis that the intrauterine milieu of pregnancies complicated by maternal metabolic disease disturbs adipogenesis in the fetus, thereby accelerating the trajectory of adipose expansion in early postnatal life and predisposing to impaired adipose plasticity.

Maternal high-fat diet changes DNA methylation in the early embryo by disrupting the TCA cycle intermediary alpha ketoglutarate.

In brief: Maternal obesity can impair metabolism in the embryo and the resulting offspring. This study shows that metabolic disruptions through α-ketoglutarate may link altered metabolism with epigenetic changes in embryos. Abstract: Maternal obesity can impair offspring metabolic health; however, the precise mechanism underpinning programming is unknown. Ten-Eleven translocase (TET) enzymes demethylate DNA using the TCA cycle intermediary α-ketoglutarate and may be involved in programming offspring health. Whether TETs are disrupted by maternal obesity is unknown. Five to six week-old C57Bl/6 female mice were fed a control diet (CD; 6% fat, n = 175) or a high-fat diet (HFD; 21% fat, n = 158) for 6 weeks. After superovulation, oocytes were collected for metabolic assessment, or females were mated and zygotes were cultured for embryo development, fetal growth, and assessment of global DNA methylation (5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxycytosine (5caC)) in the two-cell embryo. Zygotes collected from superovulated CBAF1 females were cultured in media containing α-ketoglutarate (0, 1.4, 3.5, or 14.0 mM) or with 2-hydroxyglutarate (2HG) (0 or 20 mM), a competitive inhibitor of α-ketoglutarate, with methylation and blastocyst differentiation assessed. After HFD, oocytes showed increased pyruvate oxidation and intracellular ROS, with no changes in Tet3 expression, while two-cell embryo global 5hmC DNA methylation was reduced and 5fC increased. Embryos cultured with 1.4 mM α-ketoglutarate had decreased two-cell 5mC, while 14.0 mM α-ketoglutarate increased the 5hmC:5mC ratio. In contrast, supplementation with 20 mM 2HG increased 5mC and decreased 5fC:5mC and 5caC:5mC ratios. α-ketoglutarate up to 3.5 mM did not alter embryo development, while culturing in 14.0 mM α-ketoglutarate blocked development at the two-cell. Culture with 2HG delayed embryo development past the four-cell and decreased blastocyst total cell number. In conclusion, disruptions in metabolic intermediates in the preimplantation embryo may provide a link between maternal obesity and programming offspring for ill health.

Maternal obesity-induced endoplasmic reticulum stress causes metabolic alterations and abnormal hypothalamic development in the offspring.

The steady increase in the prevalence of obesity and associated type II diabetes mellitus is a major health concern, particularly among children. Maternal obesity represents a risk factor that contributes to metabolic perturbations in the offspring. Endoplasmic reticulum (ER) stress has emerged as a critical mechanism involved in leptin resistance and type 2 diabetes in adult individuals. Here, we used a mouse model of maternal obesity to investigate the importance of early life ER stress in the nutritional programming of this metabolic disease. Offspring of obese dams developed glucose intolerance and displayed increased body weight, adiposity, and food intake. Moreover, maternal obesity disrupted the development of melanocortin circuits associated with neonatal hyperleptinemia and leptin resistance. ER stress-related genes were up-regulated in the hypothalamus of neonates born to obese mothers. Neonatal treatment with the ER stress-relieving drug tauroursodeoxycholic acid improved metabolic and neurodevelopmental deficits and reversed leptin resistance in the offspring of obese dams.

Human Placental Adaptive Changes in Response to Maternal Obesity: Sex Specificities.

Maternal obesity is increasingly prevalent and is associated with elevated morbidity and mortality rates in both mothers and children. At the interface between the mother and the fetus, the placenta mediates the impact of the maternal environment on fetal development. Most of the literature presents data on the effects of maternal obesity on placental functions and does not exclude potentially confounding factors such as metabolic diseases (e.g., gestational diabetes). In this context, the focus of this review mainly lies on the impact of maternal obesity (in the absence of gestational diabetes) on (i) endocrine function, (ii) morphological characteristics, (iii) nutrient exchanges and metabolism, (iv) inflammatory/immune status, (v) oxidative stress, and (vi) transcriptome. Moreover, some of those placental changes in response to maternal obesity could be supported by fetal sex. A better understanding of sex-specific placental responses to maternal obesity seems to be crucial for improving pregnancy outcomes and the health of mothers and children.

Placentas delivered by pre-pregnant obese women have reduced abundance and diversity in the microbiome.

Maternal pre-pregnancy obesity may have an impact on both maternal and fetal health. We examined the microbiome recovered from placentas in a multi-ethnic maternal pre-pregnant obesity cohort, through an optimized microbiome protocol to enrich low bacterial biomass samples. We found that the microbiomes recovered from the placentas of obese pre-pregnant mothers are less abundant and less diverse when compared to those from mothers of normal pre-pregnancy weight. Microbiome richness also decreases from the maternal side to the fetal side, demonstrating heterogeneity by geolocation within the placenta. In summary, our study shows that the microbiomes recovered from the placentas are associated with pre-pregnancy obesity. IMPORTANCE: Maternal pre-pregnancy obesity may have an impact on both maternal and fetal health. The placenta is an important organ at the interface of the mother and fetus, and supplies nutrients to the fetus. We report that the microbiomes enriched from the placentas of obese pre-pregnant mothers are less abundant and less diverse when compared to those from mothers of normal pre-pregnancy weight. More over, the microbiomes also vary by geolocation within the placenta.

Male Rat Offspring Are More Impacted by Maternal Obesity Induced by Cafeteria Diet than Females-Additive Effect of Postweaning Diet.

Maternal obesity increases the risk of health complications in offspring, but whether these effects are exacerbated by offspring exposure to unhealthy diets warrants further investigation. Female Sprague-Dawley rats were fed either standard chow (n = 15) or 'cafeteria' (Caf, n = 21) diets across pre-pregnancy, gestation, and lactation. Male and female offspring were weaned onto chow or Caf diet (2-3/sex/litter), forming four groups; behavioural and metabolic parameters were assessed. At weaning, offspring from Caf dams were smaller and lighter, but had more retroperitoneal (RP) fat, with a larger effect in males. Maternal Caf diet significantly increased relative expression of ACACA and Fasn in male and female weanling liver, but not CPT-1, SREBP and PGC1; PPARα was increased in males from Caf dams. Maternal obesity enhanced the impact of postweaning Caf exposure on adult body weight, RP fat, liver mass, and plasma leptin in males but not females. Offspring from Caf dams appeared to exhibit reduced anxiety-like behaviour on the elevated plus maze. Hepatic CPT-1 expression was reduced only in adult males from Caf fed dams. Post weaning Caf diet consumption did not alter liver gene expression in the adult offspring. Maternal obesity exacerbated the obesogenic phenotype produced by postweaning Caf diet in male, but not female offspring. Thus, the impact of maternal obesity on adiposity and liver gene expression appeared more marked in males. Our data underline the sex-specific detrimental effects of maternal obesity on offspring.

Perinatal Obesity Induces Hepatic Growth Restriction with Increased DNA Damage Response, Senescence, and Dysregulated Igf-1-Akt-Foxo1 Signaling in Male Offspring of Obese Mice.

Maternal obesity predisposes for hepato-metabolic disorders early in life. However, the underlying mechanisms causing early onset dysfunction of the liver and metabolism remain elusive. Since obesity is associated with subacute chronic inflammation and accelerated aging, we test the hypothesis whether maternal obesity induces aging processes in the developing liver and determines thereby hepatic growth. To this end, maternal obesity was induced with high-fat diet (HFD) in C57BL/6N mice and male offspring were studied at the end of the lactation [postnatal day 21 (P21)]. Maternal obesity induced an obese body composition with metabolic inflammation and a marked hepatic growth restriction in the male offspring at P21. Proteomic and molecular analyses revealed three interrelated mechanisms that might account for the impaired hepatic growth pattern, indicating prematurely induced aging processes: (1) Increased DNA damage response (γH2AX), (2) significant upregulation of hepatocellular senescence markers (Cdnk1a, Cdkn2a); and (3) inhibition of hepatic insulin/insulin-like growth factor (IGF)-1-AKT-p38-FoxO1 signaling with an insufficient proliferative growth response. In conclusion, our murine data demonstrate that perinatal obesity induces an obese body composition in male offspring with hepatic growth restriction through a possible premature hepatic aging that is indicated by a pathologic sequence of inflammation, DNA damage, senescence, and signs of a possibly insufficient regenerative capacity.

Do variations in insulin sensitivity and insulin secretion in pregnancy predict differences in obstetric and neonatal outcomes?

AIMS/HYPOTHESIS: Gestational diabetes mellitus (GDM) is generally defined based on glycaemia during an OGTT, but aetiologically includes women with defects in insulin secretion, insulin sensitivity or a combination of both. In this observational study, we aimed to determine if underlying pathophysiological defects evaluated as continuous variables predict the risk of important obstetric and neonatal outcomes better than the previously used dichotomised or categorical approaches. METHODS: Using data from blinded OGTTs at mean gestational week 28 from five Hyperglycemia and Adverse Pregnancy Outcome study centres, we estimated insulin secretion (Stumvoll first phase) and sensitivity (Matsuda index) and their product (oral disposition index [DI]) in 6337 untreated women (1090 [17.2%] with GDM as defined by the International Association of Diabetes and Pregnancy Study Groups). Rather than dichotomising these variables (i.e. GDM yes/no) or subtyping by insulin impairment, we related insulin secretion and sensitivity as continuous variables, along with other maternal characteristics, to obstetric and neonatal outcomes using multiple regression and receiver operating characteristic curve analysis. RESULTS: Stratifying by GDM subtype offered superior prediction to GDM yes/no only for neonatal hyperinsulinaemia and pregnancy-related hypertension. Including the DI and the Matsuda score significantly increased the area under the receiver operating characteristic curve (AUROC) and improved prediction for multiple outcomes (large for gestational age [AUROC 0.632], neonatal adiposity [AUROC 0.630], pregnancy-related hypertension [AUROC 0.669] and neonatal hyperinsulinaemia [AUROC 0.688]). Neonatal hypoglycaemia was poorly predicted by all models. Combining the DI and the Matsuda score with maternal characteristics substantially improved the predictive power of the model for large for gestational age, neonatal adiposity and pregnancy-related hypertension. CONCLUSION/INTERPRETATION: Continuous measurement of insulin secretion and insulin sensitivity combined with basic clinical variables appeared to be superior to GDM (yes/no) or subtyping by insulin secretion and/or sensitivity impairment in predicting obstetric and neonatal outcomes in a multi-ethnic cohort. Graphical abstract.

Maternal obesity during pregnancy leads to adipose tissue ER stress in mice via miR-126-mediated reduction in Lunapark.

AIMS/HYPOTHESIS: Levels of the microRNA (miRNA) miR-126-3p are programmed cell-autonomously in visceral adipose tissue of adult offspring born to obese female C57BL/6J mice. The spectrum of miR-126-3p targets and thus the consequences of its dysregulation for adipocyte metabolism are unknown. Therefore, the aim of the current study was to identify novel targets of miR-126-3p in vitro and then establish the outcomes of their dysregulation on adipocyte metabolism in vivo using a well-established maternal obesity mouse model. METHODS: miR-126-3p overexpression in 3T3-L1 pre-adipocytes followed by pulsed stable isotope labelling by amino acids in culture (pSILAC) was performed to identify novel targets of the miRNA. Well-established bioinformatics algorithms and luciferase assays were then employed to confirm those that were direct targets of miR-126-3p. Selected knockdown experiments were performed in vitro to define the consequences of target dysregulation. Quantitative real-time PCR, immunoblotting, histology, euglycaemic-hyperinsulinaemic clamps and glucose tolerance tests were performed to determine the phenotypic and functional outcomes of maternal programmed miR-126-3p levels in offspring adipose tissue. RESULTS: The proteomic approach confirmed the identity of known targets of miR-126-3p (including IRS-1) and identified Lunapark, an endoplasmic reticulum (ER) protein, as a novel one. We confirmed by luciferase assay that Lunapark was a direct target of miR-126-3p. Overexpression of miR-126-3p in vitro led to a reduction in Lunapark protein levels and increased Perk (also known as Eif2ak3) mRNA levels and small interference-RNA mediated knockdown of Lunapark led to increased Xbp1, spliced Xbp1, Chop (also known as Ddit3) and Perk mRNA levels and an ER stress transcriptional response in 3T3-L1 pre-adipocytes. Consistent with the results found in vitro, increased miR-126-3p expression in adipose tissue from adult mouse offspring born to obese dams was accompanied by decreased Lunapark and IRS-1 protein levels and increased markers of ER stress. At the whole-body level the animals displayed glucose intolerance. CONCLUSIONS/INTERPRETATION: Concurrently targeting IRS-1 and Lunapark, a nutritionally programmed increase in miR-126-3p causes adipose tissue insulin resistance and an ER stress response, both of which may contribute to impaired glucose tolerance. These findings provide a novel mechanism by which obesity during pregnancy leads to increased risk of type 2 diabetes in the offspring and therefore identify miR-126-3p as a potential therapeutic target.

Sex differences in the impact of parental obesity on offspring cardiac SIRT3 expression, mitochondrial efficiency, and diastolic function early in life.

Previous studies suggest that parental obesity may adversely impact long-term metabolic health of the offspring. We tested the hypothesis that parental (paternal + maternal) obesity impairs cardiac function in the offspring early in life. Within 1-3 days after weaning, offspring from obese rats fed a high-fat diet (HFD-Offs) and age-matched offspring from lean rats (ND-Offs) were submitted to echocardiography and cardiac catheterization for assessment of pressure-volume relationships. Then, hearts were digested and isolated cardiomyocytes were used to determine contractile function, calcium transients, proteins related to calcium signaling, and mitochondrial bioenergetics. Female and male HFD-Offs were heavier (72 ± 2 and 61 ± 4 g vs. 57 ± 2 and 49 ± 1 g), hyperglycemic (112 ± 8 and 115 ± 12 mg/dL vs. 92 ± 10 and 96 ± 8 mg/dL) with higher plasma insulin and leptin concentrations compared with female and male ND-Offs. When compared with male controls, male HFD-Offs exhibited similar systolic function but impaired diastolic function as indicated by increased IVRT (22 ± 1 vs. 17 ± 1 ms), E/E' ratio (29 ± 2 vs. 23 ± 1), and tau (5.7 ± 0.2 vs. 4.8 ± 0.2). The impaired diastolic function was associated with reduced resting free Ca2+ levels and phospholamban protein expression, increased activated matrix metalloproteinase 2, and reduced SIRT3 protein expression, mitochondrial ATP reserve, and ATP-linked respiration. These results indicate that male and female Offs from obese parents have multiple metabolic abnormalities early in life (1-3 days after weaning) and that male, but not female, Offs have impaired diastolic function as well as reductions in cardiac SIRT3, resting free Ca2+ levels, and mitochondrial biogenesis.NEW & NOTEWORTHY Parental obesity contributes to diastolic dysfunction in young offspring (1-3 days after weaning) in a sex-dependent manner, as well as reduced cardiac SIRT3 expression and altered mitochondrial bioenergetics, resting Ca2+ levels, and reduced phospholamban protein levels.