In utero gender dimorphism of adiponectin reflects insulin sensitivity and adiposity of the fetus

Maternal obesity: sex-specific in utero changes in fetal brain autophagy and mTOR

OBJECTIVE

Maternal obesity affects 39.7% of reproductive-age women in the United States. Emerging research has suggested that in utero exposure to maternal obesity is associated with adverse neurodevelopmental outcomes, but knowledge of underlying mechanisms in human samples is lacking.

METHODS

A matched case-control study was performed in women with singleton fetuses who were undergoing elective pregnancy termination at gestational ages 15 to 21 weeks. Maternal adiponectin levels from plasma were measured using ELISA kits. RNA was extracted from fetal brain tissue using RNeasy Mini Kit (QIAGEN). mRNA expression from ADIPOR1, ADIPOR2, MTOR, ATG5, ATG7, BECN1, and MAP1LC3B was quantified through the ΔΔCt method and using GAPDH as a housekeeping gene.

RESULTS

We have identified transcription patterns associated with inhibition of autophagy in male fetal brain tissue exposed to maternal obesity (↑MTOR, ↓ATG5, ↓ATG7, and ↓MAP1LC3B), with female fetuses demonstrating either no change in transcription or nonsignificant changes associated with increased autophagy. There was significant downregulation of the autophagy-associated gene BECN1 in both male and female individuals who were exposed to obesity in utero.

CONCLUSIONS

We present novel evidence suggesting that in utero exposure to maternal obesity in humans may significantly affect neurodevelopment, especially in male fetuses, through alterations in normal autophagy molecular mechanisms and with adiponectin as a potential mediator.

Distinct cord blood C-peptide, adipokine, and lipidomic signatures by in utero HIV exposure

BACKGROUND

Early-life metabolic derangements in HIV-exposed uninfected (HEU) infants have been reported.

METHODS

Pregnant women with HIV and HIV-uninfected pregnant women were enrolled with their newborns in a US cohort from 2011 to 2015. We measured cord insulin, C-peptide, and metabolic cytokines of HEU and HIV-unexposed uninfected (HUU) newborns using ELISA and metabolites, lipid subspecies, and eicosanoids via liquid chromatography/mass spectrometry. Linear regression was employed to assess the association of intrauterine HIV/ART with insulin and C-peptide. Graphical lasso regression was used to identify differences between metabolite/lipid subspecies networks associated with C-peptide.

RESULTS

Of 118 infants, 56 were HEU, ART exposed. In adjusted analyses, mean cord insulin (β = 0.295, p = 0.03) and C-peptide (β = 0.522, p < 0.01) were significantly higher in HEU vs. HUU newborns. HEU neonates exhibited primarily positive associations between complex lipids and C-peptide, indicative of fuel storage, and augmented associations between cord eicosanoids and cytokines. HUU neonates exhibited negative associations with lipids and C-peptide indicative of increased fuel utilization.

CONCLUSION

Higher cord insulin and C-peptide in HEU vs. HUU newborns as well as differences in cord metabolites, metabolic-related cytokines, and eicosanoids may reflect a propensity for fuel storage and an inflammatory milieu suggestive of fetal metabolic changes associated with in utero HIV/ART exposure.

IMPACT

There is a paucity of studies assessing cord blood and neonatal metabolic health in HIV-exposed uninfected (HEU) newborns, an increasing population worldwide. Compared to HIV-unexposed uninfected (HUU) newborns, HEU newborns exhibit alterations in fuel homeostasis and an inflammatory milieu associated with in utero HIV/antiretroviral therapy (ART) exposure. The long-term implications of these neonatal findings are as yet unknown, but merit continued evaluation as this important and growing population ages into adulthood.

Western-style diet consumption impairs maternal insulin sensitivity and glucose metabolism during pregnancy in a Japanese macaque model

The prevalence of maternal obesity is increasing in the United States. Offspring born to women with obesity or poor glycemic control have greater odds of becoming obese and developing metabolic disease later in life. Our group has utilized a macaque model to study the metabolic effects of consumption of a calorically-dense, Western-style diet (WSD; 36.3% fat) during pregnancy. Here, our objective was to characterize the effects of WSD and obesity, alone and together, on maternal glucose tolerance and insulin levels in dams during each pregnancy. Recognizing the collinearity of maternal measures, we adjusted for confounding factors including maternal age and parity. Based on intravenous glucose tolerance tests, dams consuming a WSD showed lower glucose area under the curve during first study pregnancies despite increased body fat percentage and increased insulin area under the curve. However, with (1) prolonged WSD feeding, (2) multiple diet switches, and/or (3) increasing age and parity, WSD was associated with increasingly higher insulin levels during glucose tolerance testing, indicative of insulin resistance. Our results suggest that prolonged or recurrent calorically-dense WSD and/or increased parity, rather than obesity per se, drive excess insulin resistance and metabolic dysfunction. These observations in a highly relevant species are likely of clinical and public health importance given the comparative ease of maternal dietary modifications relative to the low likelihood of successfully reversing obesity in the course of any given pregnancy.

Antenatal Determinants of Childhood Obesity in High-Risk Offspring: Protocol for the DiGest Follow-Up Study

Childhood obesity is an area of intense concern internationally and is influenced by events during antenatal and postnatal life. Although pregnancy complications, such as gestational diabetes and large-for-gestational-age birthweight have been associated with increased obesity risk in offspring, very few successful interventions in pregnancy have been identified. We describe a study protocol to identify if a reduced calorie diet in pregnancy can reduce adiposity in children to 3 years of age. The dietary intervention in gestational diabetes (DiGest) study is a randomised, controlled trial of a reduced calorie diet provided by a whole-diet replacement in pregnant women with gestational diabetes. Women receive a weekly dietbox intervention from enrolment until delivery and are blinded to calorie allocation. This follow-up study will assess associations between a reduced calorie diet in pregnancy with offspring adiposity and maternal weight and glycaemia. Anthropometry will be performed in infants and mothers at 3 months, 1, 2 and 3 years post-birth. Glycaemia will be assessed using bloodspot C-peptide in infants and continuous glucose monitoring with HbA1c in mothers. Data regarding maternal glycaemia in pregnancy, maternal nutrition, infant birthweight, offspring feeding behaviour and milk composition will also be collected. The DiGest follow-up study is expected to take 5 years, with recruitment finishing in 2026.

Oxidized LDL, insulin sensitivity and beta-cell function in newborns

INTRODUCTION

Oxidized low-density lipoprotein (OxLDL), a biomarker of oxidative stress, itself possesses proatherogenic and proinflammatory effects. Elevated circulating OxLDL levels have been consistently associated with insulin resistance and diabetes in adults. We sought to assess whether OxLDL may be associated with insulin sensitivity and beta-cell function in early life.

RESEARCH DESIGN AND METHODS

In a birth cohort study, we assessed cord plasma OxLDL concentration and OxLDL to total LDL ratio in relation to glucose to insulin ratio (an indicator of fetal insulin sensitivity), proinsulin to insulin ratio (an indicator of fetal beta-cell function), and leptin and adiponectin concentrations in 248 singleton newborns.

RESULTS

Cord plasma OxLDL concentration was positively correlated with glucose to insulin ratio (r=0.24, p<0.001) and proinsulin to insulin ratio (r=0.20, p<0.001) and was not correlated with leptin or adiponectin. Adjusting for maternal and neonatal characteristics, each log unit increase in cord plasma OxLDL concentration was associated with a 25.8% (95% CI 12.8% to 40.3%) increase in glucose to insulin ratio and a 19.0% (95% CI 6.8% to 32.9%) increase in proinsulin to insulin ratio, respectively. Similar associations were observed for cord plasma OxLDL to LDL ratio in relation to cord plasma glucose to insulin ratio and proinsulin to insulin ratio.

CONCLUSIONS

Higher OxLDL levels were associated with lower fetal beta-cell function (higher proinsulin to insulin ratio) but higher insulin sensitivity (higher glucose to insulin ratio). The study is the first to demonstrate that OxLDL may affect glucose metabolic health in early life in humans.

Cord Blood Adipocytokines and Body Composition in Early Childhood: A Systematic Review and Meta-Analysis

Childhood obesity is a growing epidemic. Early identification of high-risk groups will allow for the development of prevention strategies. Cord blood adipocytokines have been previously examined as biomarkers predicting future obesity. We conducted a systematic review looking at the association between cord blood leptin and adiponectin with adiposity up to 5 years of age. A literature review was performed between January 1994 and August 2020 using two bibliographic databases (Medline/Pubmed and EMBASE) and was registered on PROSPERO (CRD42017069024). Studies using skinfold thickness and direct methods of assessing body composition in full term neonates were considered. Partial correlation and multiple regression models were used to present the results. Meta-analysis was performed, were possible, using a random effects model. Cochran’s Q test was used to assess heterogeneity and I² statistics to calculate the percentage of variation across studies. The potential for publication bias was assessed using funnel plots. Data from 22 studies were retrieved and reviewed by two independent reviewers. Cord blood leptin was positively associated with adiposity at birth (r = 0.487; 95% CI: 0.444, 0.531) but was inversely related to adiposity up to 3 years of age. The association was not sustained at 5 years. There was a weak positive association between adiponectin in cord blood and adiposity at birth (r = 0.201; 95% CI: 0.125, 0.277). No correlation was found between cord blood adiponectin in young children, but data were limited. This review supports that cord blood leptin and adiponectin are associated with adiposity at birth. The results of this study provide insight into the role of adipocytokines at birth on future metabolic health and their potential use as risk stratification tools.

Adipose tissue development and lipid metabolism in the human fetus: The 2020 perspective focusing on maternal diabetes and obesity

During development, the human fetus accrues the highest proportion of fat of all mammals. Precursors of fat lobules can be found at week 14 of pregnancy. Thereafter, they expand, filling with triacylglycerols during pregnancy. The resultant mature lipid-filled adipocytes emerge from a developmental programme of embryonic stem cells, which is regulated differently than adult adipogenesis. Fetal triacylglycerol synthesis uses glycerol and fatty acids derived predominantly from glycolysis and lipogenesis in liver and adipocytes. The fatty acid composition of fetal adipose tissue at the end of pregnancy shows a preponderance of palmitic acid, and differs from the mother. Maternal diabetes mellitus does not influence this fatty acid profile. Glucose oxidation is the main source of energy for the fetus, but mitochondrial fatty acid oxidation also contributes. Indirect evidence suggests the presence of lipoprotein lipase in fetal adipose tissue. Its activity may be increased under hyperinsulinemic conditions as in maternal diabetes mellitus and obesity, thereby contributing to increased triacylglycerol deposition found in the newborns of such pregnancies. Fetal lipolysis is low. Changes in the expression of genes controlling metabolism in fetal adipose tissue appear to contribute actively to the increased neonatal fat mass found in diabetes and obesity. Many of these processes are under endocrine regulation, principally by insulin, and show sex-differences. Novel fatty acid derived signals such as oxylipins are present in cord blood with as yet undiscovered function. Despite many decades of research on fetal lipid deposition and metabolism, many key questions await answers.

Sex dimorphism in the associations of gestational diabetes with cord blood adiponectin and retinol-binding protein 4

INTRODUCTION

Gestational diabetes (GD) is associated with impaired insulin sensitivity in newborns. Adiponectin and retinol-binding protein 4 (RBP-4) are involved in regulating insulin sensitivity. Females are more likely to develop diabetes at young ages than males. We tested the hypothesis that GD may affect RBP-4 and adiponectin levels in early life, and there may be sex-dimorphic associations.

RESEARCH DESIGN AND METHODS

In a nested case-control study of 153 matched pairs of neonates of mothers with GD and euglycemic pregnancies in the Shanghai Birth Cohort, we evaluated cord plasma leptin, high molecular weight (HMW) and total adiponectin and RBP-4 concentrations.

RESULTS

Comparing GD versus euglycemic pregnancies adjusted for maternal and neonatal characteristics in female newborns, cord plasma total adiponectin (mean±SD: 30.8±14.3 vs 37.1±16.1 µg/mL, p=0.048) and HMW adiponectin (14.6±7.7 vs 19.3±8.3 µg/mL, p=0.004) concentrations were lower, while RBP-4 concentrations were higher (21.7±5.4 vs 20.0±4.8 µg/mL, p=0.007). In contrast, there were no differences in male newborns (all p>0.2). RBP-4 concentrations were higher in female versus male newborns (21.7±5.4 vs 18.8±4.5 µg/mL, p<0.001) in GD pregnancies only. HMW adiponectin concentrations were significantly higher in female versus male newborns in euglycemic pregnancies only (19.3±8.3 vs 16.1±7.4 µg/mL, p=0.014).

CONCLUSIONS

GD was associated with lower cord plasma HMW adiponectin and higher RBP-4 concentrations in female newborns only. The study is the first to reveal a sex-dimorphic early life impact of GD on metabolic health biomarkers in the offspring. GD may alter the normal presence (HMW adiponectin) or absence (RBP-4) of sex dimorphism in some insulin sensitivity regulation-relevant adipokines in early life.

FIGO analysis of research priorities in hyperglycemia in pregnancy

Hyperglycemia in pregnancy (HIP) is recognized as a major underlying cause of pregnancy complications and a contributing cause to health risks throughout the subsequent life of both mothers and babies, with amplification of the global epidemic of non-communicable diseases. Although some aspects of these associations are well described, detailed understanding of basic pathophysiologic mechanisms is lacking. Improved fundamental scientific knowledge must be developed to allow logical strategies for prevention and treatment. During pregnancy, much work is required to replace current empirical approaches to diagnosis and treatment of HIP with evidence based protocols, pragmatically adapted to differing health care and health economic contexts. Further, a life cycle approach to HIP, the risk of immediate pregnancy complications and later health risks to mother and baby must be developed and implemented across a wide range of health care environments. This document aims to outline key focus areas for further basic, epidemiologic, clinical and implementation research in this important area.

Large-for-Gestational-Age May Be Associated With Lower Fetal Insulin Sensitivity and β-Cell Function Linked to Leptin

CONTEXT

Fetal overgrowth is associated with increased risk for type 2 diabetes in adulthood. It is unclear whether there are alterations in insulin sensitivity and β-cell function in early life.

OBJECTIVE

To determine whether large-for-gestational-age (LGA) (birth weight > 90th percentile), an indicator of fetal overgrowth, is associated with altered fetal insulin sensitivity and β-cell function.

STUDY DESIGN, POPULATION, AND OUTCOMES

In the Design, Development, and Discover birth cohort in Canada, we studied 106 pairs of LGA and optimal-for-gestational-age (OGA; birth weight, 25th to 75th percentiles) infants matched by maternal ethnicity, smoking status, and gestational age. Cord plasma glucose-to-insulin ratio was used as an indicator of fetal insulin sensitivity, and proinsulin-to-insulin ratio was used as an indicator of β-cell function. Cord plasma leptin and high-molecular-weight (HMW) adiponectin concentrations were measured.

RESULTS

Comparisons of infants who were born LGA vs OGA, adjusted for maternal and newborn characteristics, showed that cord blood insulin, proinsulin, and leptin concentrations were significantly higher, whereas HWM adiponectin concentrations were similar. Glucose-to-insulin ratios were significantly lower (15.4 ± 28.1 vs 22.0 ± 24.9; P = 0.004), and proinsulin-to-insulin ratios significantly higher (0.73 ± 0.82 vs 0.60 ± 0.78; P = 0.005) in LGA vs OGA newborns, indicating lower insulin sensitivity and β-cell function in LGA newborns. These significant differences were almost unchanged after further adjustment for cord blood adiponectin levels but disappeared upon additional adjustment for cord blood leptin levels.

CONCLUSIONS

This study demonstrates that LGA may be associated with decreases in both fetal insulin sensitivity and β-cell function. The alterations appear to be linked to elevated leptin levels.

Neurobiological characteristics underlying metabolic differences between males and females

The hypothalamus is the main integrating center for metabolic control. Our understanding of how hypothalamic circuits function to control appetite and energy expenditure has increased dramatically in recent years, due to the rapid rise in the incidence of obesity and the search for effective treatments. Increasing evidence indicates that these treatments will most likely differ between males and females. Indeed, sex differences in metabolism have been demonstrated at various levels, including in two of the most studied neuronal populations involved in metabolic control: the anorexigenic proopiomelanocortin neurons and the orexigenic neuropeptide Y/Agouti-related protein neurons. Here we review what is known to date regarding the sex differences in these two neuronal populations, as well as other neuronal populations involved in metabolic control and glial cells.

Effects of maternal obesity on maternal and fetal plasma concentrations of adiponectin and expression of adiponectin and its receptor genes in cotyledonary and adipose tissues at mid- and late-gestation in sheep

Adiponectin potentially influences fetal weight by altering insulin signaling and trans-placental amino acid and glucose transporters. The objective of this study was to determine how maternal obesity influences maternal and fetal plasma concentrations of adiponectin, expression of fetal adiponectin, its receptors, and adipogenic genes at mid- and late-gestation. Blood samples and tissues were collected from obese and control multiparous pregnant ewes at day 75 or 135 of gestation. Although day of gestation or maternal obesity did not influence (P >  0.6) maternal plasma concentrations of adiponectin, fetal weight was increased (P <  0.001) and adiponectin tended to decrease (P =  0.10) at mid-gestation in fetuses from obese ewes. Differences were not apparent at late-gestation (P > 0.70). Relative abundance of adiponectin (P =  0.01), AdipoR2 (P =  0.04) and PPARγ (P =  0.01) mRNA was less at mid-gestation in fetal adipose tissue from obese mothers. By late gestation, maternal obesity tended to associated with a decrease in relative abundance of adiponectin (P =  0.09) and SREBF1 (P =  0.10) mRNA in fetal adipose tissue. Maternal obesity did not influence (P ≥  0.20) the relative abundance of adiponectin, AdipoR1 and AdipoR2 mRNA in cotyledonary tissue at mid or late- gestation. In conclusion, maternal obesity in sheep influences relative abundance of fetal adipose tissue mRNA for adiponectin and adipogenic, as well as plasma concentrations of total adiponectin. Although adiposity in pregnant ewes did not influence maternal adiponectin, maternal obesity potentially influenced fetal adipogenesis by altering the abundance of adiponectin, PPARγ and SREBF1 mRNA in fetal adipose tissue.

Cord blood concentrations of leptin, zinc-α2-glycoprotein, and adiponectin, and adiposity gain during the first 3 mo of life

OBJECTIVES

Adipose tissue development starts in intrauterine life and cytokines are involved in this process. Therefore, understanding the role of cytokines in the fat mass gain of infants is crucial to prevent obesity later in life. Furthermore, recent evidence indicates a sex-specific link between cytokines and adipose tissue development. The objective of this study was to assess sex-specific relationships of cord blood concentrations of the cytokines leptin, zinc-α2-glycoprotein (ZAG), and adiponectin with infant adiposity during the first 3 mo of life.

METHODS

This was a prospective cohort study of 104 mother-infant pairs that were selected from a maternity hospital in Sao Paulo, Brazil. Cord blood leptin, ZAG, and adiponectin were determined by enzyme-linked immunosorbent assays. The body composition of the infants was assessed monthly by air displacement plethysmography. A multiple linear regression analysis was conducted with the average fat mass gain from birth to the third month of life as the outcome and cord blood leptin, ZAG, and adiponectin as the variables of interest.

RESULTS

Leptin was inversely associated with fat mass gain in the first 3 mo of life (P = 0.003; adjusted R² = 0.09). There were inverse associations of leptin (P = 0.021), ZAG (P = 0.042), and maternal body mass index (P = 0.04) with fat mass gain in girls (adjusted R² = 0.29) but fat mass gain in boys was positively associated with gestational age (P = 0.01; adjusted R² = 0.15).

CONCLUSIONS

The results of this study suggest that adiposity programming is sex-specific, which highlights the need to investigate the different metabolic mechanisms that are involved in adipogenesis.

Implications of Lipids in Neonatal Body Weight and Fat Mass in Gestational Diabetic Mothers and Non-Diabetic Controls

PURPOSE OF REVIEW

Maternal lipid metabolism greatly changes during pregnancy and we review in this article how they influence fetal adiposity and growth under non-diabetic and gestational diabetic conditions.

RECENT FINDINGS

In pregnant women without diabetes (control), maternal glycemia correlates with neonatal glycemia, neonatal body weight and fat mass. In pregnant women with gestational diabetes mellitus (GDM), maternal glucose correlates with neither neonatal glycemia, neonatal birth weight nor fat mass, but maternal triacylglycerols (TAG), non-esterified fatty acids (NEFA) and glycerol do correlate with birth weight and neonatal adiposity. The proportions of maternal plasma arachidonic (AA) and docosahexaenoic (DHA) acids decrease from the first to the third trimester of pregnancy, and at term these long-chain polyunsaturated fatty acids are higher in cord blood plasma than in mothers, indicating efficient placental transfer. In control or pregnant women with GDM at term, the maternal concentration of individual fatty acids does not correlate with neonatal body weight or fat mass, but cord blood fatty acid levels correlate with birth weight and neonatal adiposity-positively in controls, but negatively in GDM. The proportion of AA and DHA in umbilical artery plasma in GDM is lower than in controls but not in umbilical vein plasma. Therefore, an increased utilization of those two fatty acids by fetal tissues, rather than impaired placental transfer, is responsible for their smaller proportion in plasma of GDM newborns. In control pregnant women, maternal glycemia controls neonatal body weight and fat mass, whereas in mothers with GDM-even with good glycemic control-maternal lipids and their greater utilization by the fetus play a critical role in neonatal body weight and fat mass. We propose that altered lipid metabolism rather than hyperglycemia constitutes a risk for macrosomia in GDM.

Placental ghrelin and leptin expression and cord blood ghrelin, adiponectin, leptin, and C-peptide levels in severe maternal obesity

PURPOSE

The purpose of this study is to investigate placental ghrelin and leptin expression as well as cord blood ghrelin and adiponectin levels in maternal obesity and associations between placental ghrelin expression, cord blood ghrelin levels and maternal and infant variables.

MATERIALS AND METHODS

Placental ghrelin and leptin expression were analyzed by RT-PCR in 32 severely obese and 32 matched normal-weight women. Cord blood ghrelin, adiponectin, leptin, and C-peptide concentrations were analyzed by ELISA.

RESULTS

Neither ghrelin nor leptin expression and neither cord blood ghrelin nor adiponectin levels differed between the groups. Placental ghrelin expression was associated with BMI at delivery in the obese women (r = 0.424, p = .016) and in the infants born to normal-weight women with their weight z-scores at six (r = -0.642, p = .010), nine (r = -0.441, p = .015), and 12 months of age (r = -0.402, p = .028).

CONCLUSIONS

Placental ghrelin and leptin expression as well as cord blood ghrelin and adiponectin levels do not seem to be altered in severe maternal obesity. Placenta-derived ghrelin may influence the infants' postnatal weight gain, but possibly only when the mother has normal weight.

Leptin and adiponectin levels in discordant dichorionic twins at 72 hours of age-associations with anthropometric parameters and insulin resistance

BACKGROUND

Insulin resistance (IR) in adults has been associated with intrauterine growth restriction (IUGR). Leptin and adiponectin correlations with anthropometric parameters and IR at 72 h in discordant twins were tested.

METHODS

We included 24 discordant (birth weight discordance ≥20% in relation to the heavier cotwin) and 30 concordant (birth weight discordance ≤10%) twins.

RESULTS

A correlation between leptin (but not adiponectin) level and birth weight (BW), birth length and head circumference in IUGR twins was recorded (p<0.05). Insulin sensitivity (IS) and homeostatic model assessment (HOMA)-IR in IUGR twins were similar to appropriate-for-gestational-age cotwins and unrelated to adipokines. In IUGR twins, adiponectin and insulin associated positively. In larger concordant twins' leptin level correlated with HOMA-IR and insulin.

CONCLUSIONS

Leptin, but not adiponectin, levels correlate positively with anthropometric parameters in IUGR twins. IR in IUGR twins is unrelated to adipokines in the first few days of life.

Leptin and adiponectin levels in discordant dichorionic twins at 72 hours of age-associations with anthropometric parameters and insulin resistance

Background:

Insulin resistance (IR) in adults has been associated with intrauterine growth restriction (IUGR). Leptin and adiponectin correlations with anthropometric parameters and IR at 72 h in discordant twins were tested.

Methods:

We included 24 discordant (birth weight discordance ≥20% in relation to the heavier cotwin) and 30 concordant (birth weight discordance ≤10%) twins.

Results:

A correlation between leptin (but not adiponectin) level and birth weight (BW), birth length and head circumference in IUGR twins was recorded (p<0.05). Insulin sensitivity (IS) and homeostatic model assessment (HOMA)-IR in IUGR twins were similar to appropriate-for-gestational-age cotwins and unrelated to adipokines. In IUGR twins, adiponectin and insulin associated positively. In larger concordant twins’ leptin level correlated with HOMA-IR and insulin.

Conclusions:

Leptin, but not adiponectin, levels correlate positively with anthropometric parameters in IUGR twins. IR in IUGR twins is unrelated to adipokines in the first few days of life.

High and Low Salt Intake during Pregnancy: Impact on Cardiac and Renal Structure in Newborns

INTRODUCTION

Previous studies from our laboratory demonstrated that dietary salt overload and salt restriction during pregnancy were associated with cardiac and renal structural and/or functional alterations in adult offspring. The present study evaluated renal and cardiac structure and the local renin-angiotensin system in newborns from dams fed high-, normal- or low-salt diets during pregnancy.

METHODS

Female Wistar rats were fed low- (LS, 0.15% NaCl), normal- (NS, 1.3% NaCl) or high- (HS, 8% NaCl) salt diets during pregnancy. Kidneys and hearts were collected from newborns (n = 6-8/group) during the first 24 hours after birth to evaluate possible changes in structure using stereology. Protein expression of renin-angiotensin system components was evaluated using an indirect enzyme-linked immunosorbent assay (ELISA).

RESULTS

No differences between groups were observed in total renal volume, volume of renal compartments or number of glomeruli. The transverse diameter of the nuclei of cardiomyocytes was greater in HS than NS males in the left and right ventricles. Protein expression of the AT1 receptor was lower in the kidneys of the LS than in those of the NS and HS males but not females. Protein expression of the AT2 receptor was lower in the kidneys of the LS males and females than in those of the NS males and females.

CONCLUSION

High salt intake during pregnancy induced left and right ventricular hypertrophy in male newborns. Salt restriction during pregnancy reduced the expression of renal angiotensin II receptors in newborns.

Effect of maternal obesity with and without gestational diabetes on offspring subcutaneous and preperitoneal adipose tissue development from birth up to year-1

Background

Maternal obesity and gestational diabetes mellitus (GDM) may independently influence offspring fat mass and metabolic disease susceptibility. In this pilot study, body composition and fat distribution in offspring from obese women with and without GDM and lean women were assessed within the 1st year of life, and maternal and newborn plasma factors were related to offspring adipose tissue distribution.

Methods

Serum and plasma samples from pregnant obese women with (n = 16) or without (n = 13) GDM and normoglycemic lean women (n = 15) at 3rd trimester and offspring cord plasma were used for analyzing lipid profiles, insulin and adipokine levels. At week-1 and 6, month-4 and year-1, offspring anthropometrics and skinfold thickness (SFT) were measured and abdominal subcutaneous (SCA) and preperitoneal adipose tissue (PPA) were determined by ultrasonography.

Results

Cord insulin was significantly increased in the GDM group, whereas levels of cord leptin, total and high molecular weight (HMW) adiponectin were similar between the groups. Neonates of the GDM group showed significantly higher SFT and fat mass until week-6 and significantly increased SCA at week-1 compared to the lean group that persisted as strong trend at week-6. Interestingly, PPA in neonates of the GDM group was significantly elevated at week-1 compared to both the lean and obese group. At month-4 and year-1, significant differences in adipose tissue growth between the groups were not observed. Multiple linear regression analyses revealed that cord insulin levels are independently related to neonatal PPA that showed significant relation to PPA development at year-1. Maternal fasted C-peptide and HMW adiponectin levels at 3rd trimester emerged to be determinants for PPA at week-1.

Conclusion

Maternal pregravid obesity combined with GDM leads to newborn hyperinsulinemia and increased offspring fat mass until week-6, whereas pregravid obesity without GDM does not. This strongly suggests the pivotal role of GDM in the adverse offspring outcome. Maternal C-peptide and HMW adiponectin levels in pregnancy emerge to be predictive for elevated PPA in newborns and might be indicative for the obesity risk at later life. Altogether, the findings from our pilot study warrant evaluation in long-term studies.

Trial registration

German Clinical Trials Register DRKS00004370

Adiponectin and IGFBP-1 in the development of gestational diabetes in obese mothers

OBJECTIVE

Gestational diabetes mellitus (GDM) is more common in pregnancies complicated by obesity and both diseases increase the risk for fetal overgrowth and long-term adverse health consequences for the mother and child. Previous studies have linked low maternal serum adiponectin to GDM in normal and overweight women. We hypothesized that lower adiponectin, in particular the high-molecular-weight form, and insulin-like growth factor I (IGF-I) and its binding protein (IGFBP-1) are associated with GDM in pregnant obese Hispanic women.

METHODS

72 obese, predominantly Hispanic (92%), women were recruited at 24-28 weeks of gestation. Adiposity was assessed, fasting serum samples were collected, and glucose, insulin, triglyceride, cholesterol levels, adipokines, and hormones associated with obesity and insulin resistance were measured. 30 women had been recently diagnosed with GDM.

RESULTS

Gestational weeks, body mass index, triceps skinfold thickness, mid-arm circumference, serum leptin, IGF-I, tumor necrosis factor α, and interleukin-6 did not differ in the two groups. Obese women with GDM had significantly higher fasting glucose, A1C, triglycerides, very-low-density lipoprotein cholesterol and lower high-density lipoprotein cholesterol, adiponectin, and IGFBP-1 compared to obese women without GDM. Homeostasis model assessment of insulin resistance was positively correlated to IGF-I and negatively correlated to adiponectin.

CONCLUSIONS

Obese pregnant women with recently diagnosed GDM had a significantly exacerbated metabolic profile, low serum adiponectin and IGFBP-1 levels at 24-28 weeks of gestation, as compared to women with obesity alone. Because low adiponectin is well established to cause insulin resistance and decreased IGFBP-1 indicates increased IGF-I bioavailability, we propose that these changes are mechanistically linked to the development of GDM in obese Hispanic women.

Correlation of high-molecular-weight adiponectin and leptin concentrations with anthropometric parameters and insulin sensitivity in newborns

Objective. High-molecular-weight adiponectin (HMW-adiponectin) and leptin are two important adipokines. The aim of this study was to examine the association between the two adipokines and anthropometric measurements of neonates at birth. Furthermore, we would like to explore whether HMW-adiponectin and leptin correlate with insulin sensitivity in neonates. Methods. Venous cord blood samples were obtained from 266 full-term healthy neonates consecutively born at Peking Union Medical College Hospital. HMW-adiponectin, leptin, blood glucose, and insulin concentrations were measured. Results. HMW-adiponectin and leptin were significantly higher in females compared with males (P = 0.031 and P = 0.000, resp.). Univariate correlation analysis showed that leptin concentrations in cord blood were positively associated with gestational age, birth weight, body length, ponderal index, placenta weight, insulin, and insulin sensitivity (all P < 0.001). However, there was no correlation between cord blood HMW-adiponectin levels and foetal anthropometric measurements or foetal insulin sensitivity indicators (all P > 0.05). Multivariate linear regression analysis indicated that leptin (B = -0.126, P = 0.045) in cord blood was independently associated with insulin sensitivity. Conclusions. Leptin concentrations, but not HMW-adiponectin, were positively associated with foetal anthropometric measurements. Leptin concentrations are significantly associated with foetal insulin sensitivity, and there were no significant correlations between HMW-adiponectin levels and foetal insulin sensitivity.

Gender determines the actions of adiponectin multimers on fetal growth and adiposity

OBJECTIVE

We sought to analyze the role of cord blood adiponectin and its multimeric forms in neonatal adiposity and fetal growth velocity (FGV) during the third trimester of pregnancy according to fetal gender.

STUDY DESIGN

This was a prospective analytical observational study conducted at the Diabetes and Pregnancy Unit, University Hospital Joan XXIII, Tarragona, Spain. In all, 96 healthy pregnant women were included in the early third trimester and were followed up until delivery. Maternal blood was obtained upon recruitment, and cord blood was obtained at delivery. Serial fetal ultrasounds were performed during the third trimester to assess FGV. Skinfolds were measured after birth to assess neonatal adiposity. Adiponectin multimers were determined in maternal and cord blood.

RESULTS

In female neonates, adiposity and FGV in the late third trimester were correlated positively with cord blood insulin (r = 0.343, P = .015 and r = 0.430, P = .002, respectively) and maternal pregravid body mass index (r = 597, P < .001 and r = 0.428, P = .002, respectively), and negatively with maternal high-molecular-weight (HMW)/total adiponectin ratio (r = -0.269, P = .035 and r = -0.387, P = .005, respectively), but in the stepwise multiple regression model, the main determinants were cord blood insulin, pregravid body mass index, and cord blood HMW adiponectin. Otherwise, in male neonates, adiposity and fetal growth were correlated with cord blood low-molecular-weight adiponectin (r = 0.486, P = .003 and r = 0.394, P = .020, respectively), and it was this multimeric form that emerged as an independent determinant in the stepwise regression model.

CONCLUSION

Adiponectin seems to determine fetal growth and adipose tissue accretion, and low molecular weight is more specifically implicated in males, whereas the HMW isoform may be more important in females.

Increased cord blood angiotensin II concentration is associated with decreased insulin sensitivity in the offspring of mothers with gestational diabetes mellitus

OBJECTIVE

To determine cord blood angiotensin II (Ang II) concentration and assess its relationship to fetal insulin sensitivity in the offspring of mothers with gestational diabetes mellitus (GDM) at birth.

STUDY DESIGN

Thirty women with GDM and 30 healthy women were evaluated at elective cesarean delivery. Cord blood was obtained for measurement of Ang II, glucose and insulin. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated and used to estimate fetal insulin sensitivity.

RESULT

The offspring of mothers with GDM had higher ponderal index (PI), HOMA-IR and cord Ang II and insulin concentrations than the offspring of healthy mothers. Cord insulin concentration and HOMA-IR were positively associated with PI in all the offspring. Cord Ang II concentration was positively associated with HOMA-IR in the offspring of mothers with GDM.

CONCLUSION

Increased cord Ang II concentration is associated with decreased insulin sensitivity in the offspring of mothers with GDM.

Maternal and fetal leptin, adiponectin levels and associations with fetal insulin sensitivity

OBJECTIVE

It remains uncertain whether leptin and adiponectin levels are correlated in maternal vs. fetal circulations. Little is known about whether leptin and adiponectin affect insulin sensitivity during fetal life.

DESIGN AND METHODS

In a prospective singleton pregnancy cohort (n = 248), we investigated leptin and adiponectin concentrations in maternal (at 24-28 and 32-35 weeks of gestation) and fetal circulations, and their associations with fetal insulin sensitivity (glucose/insulin ratio, proinsulin level).

RESULTS

Comparing concentrations in cord vs. maternal blood, leptin levels were 50% lower, but adiponectin levels more than doubled. Adjusting for gestational age at blood sampling, consistent and similar positive correlations (correlation coefficients: 0.31-0.34, all P < 0.0001) were observed in leptin or adiponectin levels in maternal (at 24-28 or 32-25 weeks of gestation) vs. fetal circulations. For each SD increase in maternal plasma concentration at 24-28 weeks, cord plasma concentration increased by 12.7 (95% confidence interval 6.8-18.5) ng/ml for leptin, and 2.9 (1.8-4.0) µg/ml for adiponectin, respectively (adjusted P < 0.0001). Fetal insulin sensitivity was negatively associated with cord blood leptin (each SD increase was associated with a 5.4 (2.1-8.7) mg/dl/µU/ml reduction in cord plasma glucose/insulin ratio, and a 5.6 (3.9, 7.4) pmol/l increase in proinsulin level, all adjusted P < 0.01) but not adiponectin (P > 0.4) levels). Similar associations were observed in nondiabetic full-term pregnancies (n = 211).

CONCLUSIONS

The results consistently suggest a maternal impact on fetal leptin and adiponectin levels, which may be an early life pathway in maternal-fetal transmission of the propensity to obesity and insulin resistance.

Maternal and cord blood adiponectin multimeric forms in gestational diabetes mellitus: a prospective analysis

OBJECTIVE

To analyze the relationship between maternal adiponectin (mAdiponectin) and cord blood adiponectin (cbAdiponectin) multimeric forms (high molecular weight [HMW], medium molecular weight [MMW], and low molecular weight [LMW]) in a cohort of gestational diabetes mellitus (GDM) and normal glucose-tolerant (NGT) pregnant women.

RESEARCH DESIGN AND METHODS

A total of 212 women with a singleton pregnancy, 132 with NGT and 80 with GDM, and their offspring were studied. Maternal blood was obtained in the early third trimester and cord blood was obtained at delivery. Total adiponectin and the multimeric forms of adiponectin were determined in cord blood and maternal serum. Spearman rank correlation and stepwise linear correlation analysis were used to assess the relationship between cbAdiponectin levels and clinical and analytical parameters.

RESULTS

No differences in cbAdiponectin concentration or its multimeric forms were observed in the offspring of diabetic mothers compared with NGT mothers. The HMW-to-total adiponectin ratio was higher in cord blood than in maternal serum, whereas the MMW- and LMW-to-total adiponectin ratio was lower. Cord blood total and HMW adiponectin levels were positively correlated with birth weight and the ponderal index (PI), whereas cord blood MMW adiponectin was negatively correlated with the PI. In addition, cbAdiponectin and its multimeric forms were correlated with mAdiponectin concentrations. In the multivariate analysis, maternal multimeric forms of adiponectin emerged as independent predictors of cbAdiponectin, its multimers, and their distribution.

CONCLUSIONS

cbAdiponectin concentrations are independently related to mAdiponectin levels and unrelated to the diagnosis of GDM. Maternal multimeric forms of adiponectin are independent predictors of the concentrations of cbAdiponectin and its multimeric forms at delivery.

Association between adiposity and inflammatory markers in maternal and fetal blood in a group of Mexican pregnant women

In the present pilot study, we evaluated the effect of maternal adiposity on the plasma concentration of adipocytokines in pregnant women and their newborns. Twenty patients with term gestations without labour were initially selected by pregestational BMI and then classified into two study groups (n 10 each), according to their median value of adiposity (total body fat). Concentrations of TNF-α, IL-1β, IL-6, leptin and adiponectin in plasma of maternal peripheral blood and fetal cord blood were measured and correlated to maternal adiposity. Maternal adiposity showed a significant negative correlation with fetal adiponectin (r - 0·587, P = 0·01) and IL-6 (r - 0·466, P = 0·05), a significant positive correlation with maternal leptin (r 0·527, P = 0·02) and no correlation with TNF-α or IL-1β. Adiponectin was higher in fetal plasma than in maternal plasma (P = 0·043), but significantly lower in newborns from women with high adiposity than in newborns from women with low adiposity (P = 0·040). Our results suggest that fetuses from obese women may be less able to control inflammation, due to lower circulating anti-inflammatory adipocytokines, which could limit their optimal development or even increase the risk of abortion or preterm labour.