Adipose Tissue Development and Expansion from the Womb to Adolescence: An Overview

The Metabolic Programming of Pubertal Onset

BACKGROUND

There is increasing evidence that maternal factors such as nutritional status (both under and over-nutrition) and diabetes, alongside prenatal exposure to endocrine disrupting chemicals (EDCs), are associated with early pubertal onset in offspring. Such children are also at increased risk of the metabolic syndrome during adolescence and young adulthood.

AIM

This literature review focuses on the role of the prenatal environment in programming pubertal onset, and the impact of prenatal metabolic stressors on the declining average age of puberty.

METHOD

A review of all relevant literature was conducted in PubMed by the authors.

OUTCOME

The mechanism for this appears to be mediated through metabolic signals, such as leptin and insulin, on the kisspeptin-neuronal nitric oxide-gonadotropin releasing hormone (KiNG) axis. Exposed children have an elevated risk of childhood obesity and display a phenotype of hyperinsunlinaemia and hyperleptinaemia. These metabolic changes permit an earlier attainment of the nutritional "threshold" for puberty. Unfortunately, this cycle may be amplified across subsequent generations, however early intervention may help "rescue" progression of this programming.

Sex- and gender-based medicine in pediatric nutrition

Consistent evidence increasingly highlights the significance of integrating sex and gender medicine to ensure a precision approach according to individual patient needs. Gender discrepancies emerge across various areas, even from pediatric age. The importance of recognizing these differences in pediatric nutrition is critical for the development of targeted nutritional strategies and interventions, particularly in cases of associated pathologies, including obesity, metabolic-associated fatty liver disease, eating disorders, and inflammatory bowel disease. The review highlights the biological and sociocultural factors that contribute to different nutritional needs and health outcomes in male and female children. By examining current evidence, we underscore the necessity for precision medicine approaches in pediatric care that consider these sex- and gender-based differences. Moreover, differences in dietary requirements and dietary patterns between males and females are evident, underscoring the need for precise nutrition strategies for a more accurate management of children and adolescents. This approach is essential for improving clinical outcomes and promoting equitable healthcare practices. This review aims to provide an overview of nutrition-related medical conditions exhibiting sex- and gender-specific discrepancies, which might lead to distinct outcomes requiring unique management and prevention strategies. Future research and public health initiatives should address these differences in designing effective lifestyle education programs and nutrition interventions targeting both children and adolescents.

A Closer Look into White Adipose Tissue Biology and the Molecular Regulation of Stem Cell Commitment and Differentiation

White adipose tissue (WAT) makes up about 20-25% of total body mass in healthy individuals and is crucial for regulating various metabolic processes, including energy metabolism, endocrine function, immunity, and reproduction. In adipose tissue research, "adipogenesis" is commonly used to refer to the process of adipocyte formation, spanning from stem cell commitment to the development of mature, functional adipocytes. Although, this term should encompass a wide range of processes beyond commitment and differentiation, to also include other stages of adipose tissue development such as hypertrophy, hyperplasia, angiogenesis, macrophage infiltration, polarization, etc.… collectively, referred to herein as the adipogenic cycle. The term "differentiation", conversely, should only be used to refer to the process by which committed stem cells progress through distinct phases of subsequent differentiation. Recognizing this distinction is essential for accurately interpreting research findings on the mechanisms and stages of adipose tissue development and function. In this review, we focus on the molecular regulation of white adipose tissue development, from commitment to terminal differentiation, and examine key functional aspects of WAT that are crucial for normal physiology and systemic metabolic homeostasis.

Cardiometabolic Health in Adolescents with Obesity: The Role of Protein Intake, Diet Quality, and Physical Activity

Background: Although adolescents with obesity have an increased risk of cardiometabolic disease, a subset maintains a healthy cardiometabolic profile. Unhealthy lifestyle behaviors may determine cardiometabolic risk. We aimed to characterize the lifestyle behaviors of adolescents with obesity, compare differences between metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO), and assess associations between lifestyle behaviors and cardiometabolic profiles. Methods: Participants aged 10-18 years with body mass index (BMI) ≥ 95th percentile were included. Dietary intake (DI) was estimated from 3-day food records, and diet quality (DQ) was assessed using the Healthy Eating Index-Canadian Adaptation. Physical activity (PA), body composition, anthropometrics, blood markers, and blood pressure (BP) were objectively measured. MUO was defined as having high triglycerides, BP, glucose, or low high-density lipoprotein. Regression analyses were performed between lifestyle behaviors and cardiometabolic markers. Results: Thirty-nine participants (BMI z-score 2.8 [2.5-3.5], age 12.5 [10.9-13.5] years, 56.4% female) were included. A high proportion of participants failed to meet lifestyle recommendations, particularly for DQ (94.7%, n = 36), fiber (94.7%, n = 36), and PA (90.9%, n = 30). No differences in lifestyle behaviors were found between MUO (59.0%, n = 22) and MHO (41.0%, n = 16). Protein intake was negatively associated with BMI and waist circumference z-scores, fat mass index, insulin resistance, low-density lipoprotein, and C-reactive protein, whereas higher DQ was associated with lower C-reactive protein. Higher light PA levels were associated with lower total cholesterol and triglycerides. Conclusion: Adolescents with either MUO or MHO displayed low adherence to DQ, DI, and PA recommendations; no differences in lifestyle behaviors were found. Protein intake, DQ, and PA were associated with a healthier cardiometabolic profile.

Organophosphate Ester Flame Retardants and Plasticizers in Relation to Fetal Growth in the LIFECODES Fetal Growth Study

BACKGROUND

Organophosphate esters (OPEs), used ubiquitously as flame retardants and plasticizers in consumer products, are suspected of having developmental toxicity.

OBJECTIVES

Our study aimed to estimate associations between prenatal exposure to OPEs and fetal growth, including both ultrasound (head circumference, abdominal circumference, femur length, and estimated fetal weight) and delivery [birth weight z-score, small-for-gestational age (SGA), and large-for-gestational age (LGA)] measures of growth.

METHODS

In the LIFECODES Fetal Growth Study (2008-2018), an enriched case-cohort of 900 babies born at the small and large ends of the growth spectrum, we quantified OPE biomarkers in three urine samples per pregnant participant and abstracted ultrasound and delivery measures of fetal growth from medical records. We estimated associations between pregnancy-averaged log-transformed OPE biomarkers and repeated ultrasound measures of fetal growth using linear mixed-effects models, and delivery measures of fetal growth using linear (birth weight) and logistic (SGA and LGA) regression models.

RESULTS

Most OPE biomarkers were positively associated with at least one ultrasound measure of fetal growth, but associations with delivery measures were largely null. For example, an interquartile range (IQR; 1.31  ng / mL ) increase in bis(2-chloroethyl) phosphate concentration was associated with larger z-scores in head circumference [mean difference (difference): 0.09; 95% confidence interval (CI): 0.01, 0.17], abdominal circumference (difference: 0.10; 95% CI: 0.02, 0.18), femur length (difference: 0.11; 95% CI: 0.03, 0.19), and estimated fetal weight (difference: 0.13; 95% CI: 0.04, 0.22) but not birth weight (difference: 0.04; 95% CI: - 0.08 , 0.17). At delivery, an IQR (1.00  ng / mL ) increase in diphenyl phosphate (DPHP) concentration was associated with an SGA birth (odds ratio: 1.46; 95% CI: 1.10, 1.94).

CONCLUSIONS

In a large prospective cohort, gestational OPE exposures were associated with larger fetal size during pregnancy, but associations at delivery were null. DPHP concentrations were associated with heightened risk of an SGA birth. These findings suggest that OPE exposure may affect fetal development. https://doi.org/10.1289/EHP14647.

Effects of maternal exercise on infant mesenchymal stem cell mitochondrial function, insulin action, and body composition in infancy

Maternal exercise (ME) has been established as a useful non-pharmacological intervention to improve infant metabolic health; however, mechanistic insight behind these adaptations remains mostly confined to animal models. Infant mesenchymal stem cells (MSCs) give rise to infant tissues (e.g., skeletal muscle), and remain involved in mature tissue maintenance. Importantly, these cells maintain metabolic characteristics of an offspring donor and provide a model for the investigation of mechanisms behind infant metabolic health improvements. We used undifferentiated MSC to investigate if ME affects infant MSC mitochondrial function and insulin action, and if these adaptations are associated with lower infant adiposity. We found that infants from exercising mothers have improvements in MSC insulin signaling related to higher MSC respiration and fat oxidation, and expression and activation of energy-sensing and redox-sensitive proteins. Further, we found that infants exposed to exercise in utero were leaner at 1 month of age, with a significant inverse correlation between infant MSC respiration and infant adiposity at 6 months of age. These data suggest that infants from exercising mothers are relatively leaner, and this is associated with higher infant MSC mitochondrial respiration, fat use, and insulin action.

Effects of fat sources on liver characteristics and intestinal morphometry in an early-life animal model

Motivation for the study. There is little evidence on whether the consumption of fat sources containing different proportions of fatty acids has an effect on the characteristics of the liver and small intestine at an early age. Main findings. We found that the intake of fat sources containing unsaturated fatty acids contributes to maintaining the characteristics of both organs; whereas, consumption of sources containing saturated fatty acids favors inflammation in the liver and small intestine. Implications. The consumption of quinoa oil constitutes an alternative to protect these noble organs in an animal model at an early age. We aimed to determine the effect of the consumption of three sources of fatty acids on the relative weight, macroscopic and microscopic characteristics of the liver, and intestinal morphometry in an early-life animal model. Seventy-six randomly distributed chicks received one of the diets (T1: 97.0% basal diet (BD) + 3.0% inert material, T2: 97.0% BD + 3.0% partially hydrogenated vegetable shortening, T3: 97.0% BD + 3.0% quinoa oil, and T4: 97.0% BD + 3.0% fish oil) until the seventh day of life; samples were then extracted in order to be analyzed. We found that the animals that consumed quinoa oil (T3) or fish oil (T4) had favorable results associated to lower liver weight and better absorption of nutrients at intestinal level due to higher values in the hair length and crypt depth ratio, in comparison to partially hydrogenated vegetable shortening (T2). In conclusion, quinoa oil constitutes a healthy option for consumption and an alternative source to fish oil.

The metabolic load-capacity model and cardiometabolic health in children and youth with obesity

BACKGROUND

The metabolic load-capacity index (LCI), which represents the ratio of adipose to skeletal muscle tissue-containing compartments, is potentially associated with cardiometabolic diseases.

OBJECTIVES

To examine the associations between the LCI and cardiometabolic risk factors in children and youth with obesity.

METHODS

This is a cross-sectional study including 10-18 years-old participants with a BMI of ≥95th . LCI by air-displacement plethysmography (ADP) was calculated as fat mass divided by fat-free mass, and LCI by ultrasound (US) as subcutaneous adipose tissue divided by skeletal muscle thickness. Sex-specific medians stratified participants into high versus low LCI. Single (inflammation, insulin resistance, dyslipidemia and hypertension) and clustered cardiometabolic risk factors were evaluated. Linear and logistic regression models tested the associations between these variables, adjusted for sexual maturation.

RESULTS

Thirty-nine participants (43.6% males; 59% mid-late puberty) aged 12.5 (IQR: 11.1-13.5) years were included. LCI by ADP was positively associated with markers of inflammation and dyslipidemia; having a higher LCI predicted dyslipidemia in logistic regression. Similarly, LCI by US was positively associated with markers of dyslipidemia and blood pressure. In mid-late pubertal participants, LCI by US was positively associated with markers of insulin resistance and inflammation.

CONCLUSIONS

Participants with unfavourable cardiometabolic profile had higher LCI, suggesting its potential use for predicting and monitoring cardiometabolic health in clinical settings.

Obesity: a gender-view

PURPOSE

There is a growing awareness of the importance of understanding gender differences in obesity. The aim of this short review was to revise the current evidence on anthropometric characteristics and nutritional and pharmacological aspects of obesity from a gender perspective.

METHODS

A literature search within PubMed was performed. Selected publications related to obesity and gender differences were reviewed.

RESULTS

The prevalence of obesity among men is higher than in women, but women have a higher percentage of body fat content compared to men, and gender appears to be an important factor in the manifestation of central (android) or peripheral (gynoid) obesity. In addition, while in most clinical trials, women are still underrepresented, in clinical registration trials of anti-obesity drugs, women are commonly up-represented and gender-specific analysis is uncommon. Considering that adipose tissue is one of the factors affecting the volume of distribution of many drugs, mainly lipophilic drugs, gender differences might be expected in the pharmacokinetics and pharmacodynamics of anti-obesity drugs. Indeed, although Liraglutide 3 mg, a long-acting glucagon-like peptide-1 receptor agonist, and naltrexone/bupropion display lipophilic properties, currently, a gender-dose adjustment for both these drugs administration is not recommended. In addition, despite that predicted responders to treatment offer substantial opportunities for efficient use, especially of expensive new therapies, such as anti-obesity drugs, data on gender differences to identify early responders to both these have not yet been investigated. Finally, bariatric surgery gender disparity reflects healthcare practices. Weight loss similar, but differing effects: women need more correction and face psychology challenges; men have worse physiology and fewer comorbidity improvements.

CONCLUSION

Gender differences exist in obesity prevalence and phenotype, body fat distribution, drug efficacy, clinical trial representation, and different secondary effects of bariatric surgery. Gender is an important variable in obesity analysis.

Gestational Caloric Restriction Alters Adipose Tissue Methylome and Offspring's Metabolic Profile in a Swine Model

Limited nutrient supply to the fetus results in physiologic and metabolic adaptations that have unfavorable consequences in the offspring. In a swine animal model, we aimed to study the effects of gestational caloric restriction and early postnatal metformin administration on offspring's adipose tissue epigenetics and their association with morphometric and metabolic variables. Sows were either underfed (30% restriction of total food) or kept under standard diet during gestation, and piglets were randomly assigned at birth to receive metformin (n = 16 per group) or vehicle treatment (n = 16 per group) throughout lactation. DNA methylation and gene expression were assessed in the retroperitoneal adipose tissue of piglets at weaning. Results showed that gestational caloric restriction had a negative effect on the metabolic profile of the piglets, increased the expression of inflammatory markers in the adipose tissue, and changed the methylation of several genes related to metabolism. Metformin treatment resulted in positive changes in the adipocyte morphology and regulated the methylation of several genes related to atherosclerosis, insulin, and fatty acids signaling pathways. The methylation and gene expression of the differentially methylated FASN, SLC5A10, COL5A1, and PRKCZ genes in adipose tissue associated with the metabolic profile in the piglets born to underfed sows. In conclusion, our swine model showed that caloric restriction during pregnancy was associated with impaired inflammatory and DNA methylation markers in the offspring's adipose tissue that could predispose the offspring to later metabolic abnormalities. Early metformin administration could modulate the size of adipocytes and the DNA methylation changes.

The transplantation of the gut microbiome of fat-1 mice protects against colonic mucus layer disruption and endoplasmic reticulum stress induced by high fat diet

High-fat diets alter gut barrier integrity, leading to endotoxemia by impacting epithelial functions and inducing endoplasmic reticulum (ER) stress in intestinal secretory goblet cells. Indeed, ER stress, which is an important contributor to many chronic diseases such as obesity and obesity-related disorders, leads to altered synthesis and secretion of mucins that form the protective mucus barrier. In the present study, we investigated the relative contribution of omega-3 polyunsaturated fatty acid (PUFAs)-modified microbiota to alleviating alterations in intestinal mucus layer thickness and preserving gut barrier integrity. Male fat-1 transgenic mice (exhibiting endogenous omega-3 PUFAs tissue enrichment) and wild-type (WT) littermates were fed either an obesogenic high-fat diet (HFD) or a control diet. Unlike WT mice, HFD-fed fat-1 mice were protected against mucus layer alterations as well as an ER stress-mediated decrease in mucin expression. Moreover, cecal microbiota transferred from fat-1 to WT mice prevented changes in the colonic mucus layer mainly through colonic ER stress downregulation. These findings highlight a novel feature of the preventive effects of omega-3 fatty acids against intestinal permeability in obesity-related conditions.

Role of FGF21 and Leptin for the Diagnosis of Metabolic Health in Children with and without Obesity

Obesity and unfavorable metabolic profiles increase the risk for cardiovascular complications in adults. Although it is important to distinguish different metabolic health states at an early stage, there are limited data on the related value of biomarkers in childhood. We aimed to identify biomarkers for the detection of different metabolic health states in children with and without obesity. The serum levels of metabolic regulators (fibroblast growth factor 21 [FGF21], leptin, adiponectin and insulin-like growth factor binding protein 1) and vascular indices (flow-mediated dilation [FMD] and carotid intima-media thickness) were assessed in 78 children. Differences between the metabolically healthy and unhealthy state within children with normal weight (MHN vs. MUN), and within children with overweight/obesity (MHO vs. MUO) were investigated; the discriminatory power of the biomarkers was studied. Both MUN and MUO groups expressed altered lipid and glucose homeostasis compared to their healthy counterparts. The metabolic unhealthy state in children with normal weight was linked to higher FGF21 levels which had good discriminatory ability (area under the curve [AUC]: 0.71, 95% CI: 0.54-0.88; p = 0.044). In overweight/obese children, leptin was increased in the metabolically unhealthy subgroup (AUC: 0.81, 95% CI: 0.68-0.95; p = 0.01). There was a decrease in FMD indicating worse endothelial function in overweight/obese children versus those with normal weight. Distinct states of metabolic health exist in both children with normal weight and overweight/obese children. FGF21 and leptin may help to identify the metabolic unhealthy state in children with normal weight and in overweight/obese children, respectively, early in life.

Associations between Smoking and Smoking Cessation during Pregnancy and Newborn Metabolite Concentrations: Findings from PRAMS and INSPIRE Birth Cohorts

Newborn metabolite perturbations may identify potential biomarkers or mechanisms underlying adverse, smoking-related childhood health outcomes. We assessed associations between third-trimester smoking and newborn metabolite concentrations using the Tennessee Pregnancy Risk Assessment Monitoring System (PRAMS, 2009-2019) as the discovery cohort and INSPIRE (2012-2014) as the replication cohort. Children were linked to newborn screening metabolic data (33 metabolites). Third-trimester smoking was ascertained from birth certificates (PRAMS) and questionnaires (INSPIRE). Among 8600 and 1918 mother-child dyads in PRAMS and INSPIRE cohorts, 14% and 13% of women reported third-trimester smoking, respectively. Third-trimester smoking was associated with higher median concentrations of free carnitine (C0), glycine (GLY), and leucine (LEU) at birth (PRAMS: C0: adjusted fold change 1.11 [95% confidence interval (CI) 1.08, 1.14], GLY: 1.03 [95% CI 1.01, 1.04], LEU: 1.04 [95% CI 1.03, 1.06]; INSPIRE: C0: 1.08 [95% CI 1.02, 1.14], GLY: 1.05 [95% CI 1.01, 1.09], LEU: 1.05 [95% CI 1.01, 1.09]). Smoking cessation (vs. continued smoking) during pregnancy was associated with lower median metabolite concentrations, approaching levels observed in infants of non-smoking women. Findings suggest potential pathways underlying fetal metabolic programming due to in utero smoke exposure and a potential reversible relationship of cessation.

Excessive Gestational Weight Gain Alters DNA Methylation and Influences Foetal and Neonatal Body Composition

BACKGROUND

Changes in body weight are associated with the regulation of DNA methylation (DNAm). In this study, we investigated the associations between maternal gestational weight gain-related DNAm and foetal and neonatal body composition.

METHODS

Brazilian pregnant women from the Araraquara Cohort Study were followed up during pregnancy, delivery, and after hospital discharge. Women with normal pre-pregnancy BMI were allocated into two groups: adequate gestational weight gain (AGWG, n = 45) and excessive gestational weight gain (EGWG, n = 30). Foetal and neonatal body composition was evaluated via ultrasound and plethysmography, respectively. DNAm was assessed in maternal blood using Illumina Infinium MethylationEPIC BeadChip arrays. Linear regression models were used to explore the associations between DNAm and foetal and neonatal body composition.

RESULTS

Maternal weight, GWG, neonatal weight, and fat mass were higher in the EGWG group. Analysis of DNAm identified 46 differentially methylated positions and 11 differentially methylated regions (DMRs) between the EGWG and AGWG groups. Nine human phenotypes were enriched for these 11 DMRs located in 13 genes (EMILIN1, HOXA5, CPT1B, CLDN9, ZFP57, BRCA1, POU5F1, ANKRD33, HLA-B, RANBP17, ZMYND11, DIP2C, TMEM232), highlighting the terms insulin resistance, and hyperglycaemia. Maternal DNAm was associated with foetal total thigh and arm tissues and subcutaneous thigh and arm fat, as well as with neonatal fat mass percentage and fat mass.

CONCLUSION

The methylation pattern in the EGWG group indicated a risk for developing chronic diseases and involvement of maternal DNAm in foetal lean and fat mass and in neonatal fat mass.

Body composition from birth to 2 years

Providing all infants with the best start to life is a universal but challenging goal for the global community. Historically, the size and shape of infants, quantified by anthropometry and commencing with birthweight, has been the common yardstick for physical growth and development. Anthropometry has long been considered a proxy for nutritional status during infancy when, under ideal circumstances, changes in size and shape are most rapid. Developed from data collected in the Multicentre Growth Reference Study (MGRS), WHO Child Growth Standards for healthy infants and children have been widely accepted and progressively adopted. In contrast, and somewhat surprisingly, much less is understood about the 'quality' of growth as reflected by body composition during infancy. Recent advances in body composition assessment, including the more widespread use of air displacement plethysmography (ADP) across the first months of life, have contributed to a progressive increase in our knowledge and understanding of growth and development. Along with stable isotope approaches, most commonly the deuterium dilution (DD) technique, the criterion measure of total body water (TBW), our ability to quantify lean and fat tissue using a two-compartment model, has been greatly enhanced. However, until now, global reference charts for the body composition of healthy infants have been lacking. This paper details some of the historical challenges associated with the assessment of body composition across the first two years of life, and references the logical next steps in growth assessments, including reference charts.

Midpregnancy Phthalate and Phenol Biomarkers in Relation to Infant Body Composition: The Healthy Start Prospective Cohort

BACKGROUND

Gestational phthalate and phenol exposure disrupts adipogenesis, contributing to obesity in mice. Whether gestational phthalate or phenol exposure is associated with infant body composition has not been investigated in humans.

OBJECTIVE

We examined associations between biomarkers of phthalate and phenol exposure in midpregnancy and infant size and body composition at birth and at 5 months of age.

METHODS

Analyses were conducted among 438 infants from the Healthy Start prospective pregnancy cohort. Sixteen phthalate and phenol biomarkers were quantified in spot urine samples collected at 24-28 wk of gestation. Infant outcomes measured at birth and at 5 months of age included size [weight (in grams)] and body composition [fat and lean masses (in grams); percentage fat mass]. Single- (linear) and multipollutant (quantile g-computation) models were used to estimate associations of phthalate and phenol biomarkers with infant outcomes at birth and at 5 months of age. Models were adjusted for sociodemographics, sample collection timing, and lifestyle factors and used to examine for effect modification by infant sex.

RESULTS

In single-pollutant models, mono-benzyl phthalate and di-n -butyl phthalate were inversely associated with percentage fat mass [β : - 0.49 (95% CI: - 0.91 , - 0.08 ) and - 0.51 (95% CI: - 1.02 , 0.01), respectively] in male but not female infants at birth. Similar, but less precise, associations were observed at 5 months of age. In multipollutant models, a 1-quartile increase in the phthalate and phenol biomarker mixture was inversely associated with percentage fat mass at birth [- 1.06 (95% CI: - 2.21 , 0.1)] and at 5 months of age [- 2.14 (95% CI: - 3.88 , - 0.39 )] among males, but associations were null among females [0.48 (95% CI: - 0.78 , 1.75) and - 0.64 (95% CI: - 2.68 , 1.41), respectively]. Similar associations were observed with infant weight.

CONCLUSION

In this U.S.-based prospective cohort, gestational phthalate and phenol biomarkers were inversely associated with infant weight and fat mass, particularly in males. https://doi.org/10.1289/EHP12500.

Subcutaneous Adipose Tissue Transcriptome Highlights Specific Expression Profiles in Severe Pediatric Obesity: A Pilot Study

The prevalence of pediatric obesity is rising rapidly worldwide, and "omic" approaches are helpful in investigating the molecular pathophysiology of obesity. This work aims to identify transcriptional differences in the subcutaneous adipose tissue (scAT) of children with overweight (OW), obesity (OB), or severe obesity (SV) compared with those of normal weight (NW). Periumbilical scAT biopsies were collected from 20 male children aged 1-12 years. The children were stratified into the following four groups according to their BMI z-scores: SV, OB, OW, and NW. scAT RNA-Seq analyses were performed, and a differential expression analysis was conducted using the DESeq2 R package. A pathways analysis was performed to gain biological insights into gene expression. Our data highlight the significant deregulation in both coding and non-coding transcripts in the SV group when compared with the NW, OW, and OB groups. A KEGG pathway analysis showed that coding transcripts were mainly involved in lipid metabolism. A GSEA analysis revealed the upregulation of lipid degradation and metabolism in SV vs. OB and SV vs. OW. Bioenergetic processes and the catabolism of branched-chain amino acids were upregulated in SV compared with OB, OW, and NW. In conclusion, we report for the first time that a significant transcriptional deregulation occurs in the periumbilical scAT of children with severe obesity compared with those of normal weight or those with overweight or mild obesity.

White Adipose Tissue Dysfunction: Pathophysiology and Emergent Measurements

White adipose tissue (AT) dysfunction plays an important role in the development of cardiometabolic alterations associated with obesity. AT dysfunction is characterized by the loss of the expansion capacity of the AT, an increment in adipocyte hypertrophy, and changes in the secretion profile of adipose cells, associated with accumulation of macrophages and inflammation. Since not all people with an excess of adiposity develop comorbidities, it is necessary to find simple tools that can evidence AT dysfunction and allow the detection of those people with the potential to develop metabolic alterations. This review focuses on the current pathophysiological mechanisms of white AT dysfunction and emerging measurements to assess its functionality.

Growth pattern during early infancy, body mass index during childhood and childhood asthma

BACKGROUND

There is a lack of longitudinal studies of associations between growth from infancy to childhood and asthma development.

OBJECTIVE

The objective of the study was to investigate the effects of weight change during infancy, body mass index (BMI) and the interaction of these factors on the risk of childhood asthma.

METHODS

We enrolled children born in 2008 and 2009 at full-term and with normal birth weight. The weight change in infancy was grouped into slow, on-track and rapid. BMI status in childhood was stratified into low, normal and high groups and used as a time-varying variable. The outcome was asthma, defined as two or more diagnoses of asthma separated by at least 1 year after 2 years of age. The risk of asthma was assessed using Cox proportional hazard regression, with adjustment for sex, residence area at birth, economic status and feeding types in infancy.

RESULTS

Of 917,707 children born in Korea in 2008 and 2009, 271,871 were eligible for analysis. The risk of asthma was greater in groups with low birth weight (aHR 1.06, 95% CI 1.04 to 1.08), rapid body weight change during early infancy (aHR 1.08, 95% CI 1.07 to 1.10) and high BMI during childhood (aHR 1.06, 95% CI 1.04-1.08). The interaction of weight change during early infancy with BMI during childhood was significant for asthma (p < .01). Rapid weight gain in infancy was associated with lower risk of asthma in those with low BMI during childhood; had no association with asthma in those with normal BMI during childhood; and was associated increased asthma risk in those with high BMI during childhood-aHR 1.26 (95% CI 1.19 to 1.33) and aHR 1.33 (95% CI 1.12 to 1.56) compared with on-track and slow infant weight gain, respectively.

CONCLUSION

Low birth weight, high BMI during childhood and, in those with high childhood BMI, rapid weight gain during early infancy are associated with increased risk of childhood asthma.

Estimation of fat mass in Southern Brazilian female adolescents: development and validation of mathematical models

abstract This study aimed to develop and validate the first mathematical models, based on anthropometric properties, to estimate fat mass (FM) in a heterogeneous sample of female adolescents. A cross-sectional and quantitative study conducted with 196 individuals aged 12 to 17 years from the metropolitan region of Curitiba, Paraná, Brazil. The participants were randomly divided into two groups: regression sample (n = 169) and validation sample (n = 27). Dual-energy X-ray absorptiometry (DXA) was used as the reference method to determine body fat in relative and absolute values. Stature, body mass, waist girth and triceps, subscapular, biceps, iliac crest, abdominal, front thigh and medial calf skinfold thickness were defined as independent variables and measured according to an international technical protocol. Statistical analyzes used the Ordinary Least Square (OLS) regression model, paired t test and Pearson correlation. Four multivariate mathematical models with high determination coefficients (R2 ≥90%) and low estimated standard errors (SEE = ≤2.02 kg) were developed. Model 4 stands out for its low number of independent variables and significant statistical performance (R2 = 90%; SEE = 1.92 kg). It is concluded that the four mathematical models developed are valid for estimating FM in female adolescents in southern Brazil.

Differential Gene Expression of Subcutaneous Adipose Tissue among Lean, Obese, and after RYGB (Different Timepoints): Systematic Review and Analysis

The main roles of adipose tissue include triglycerides storage and adipokine secretion, which regulate energy balance and inflammation status. In obesity, adipocyte dysfunction leads to proinflammatory cytokine production and insulin resistance. Bariatric surgery is the most effective treatment for obesity, the gold-standard technique being Roux-en-Y gastric bypass (RYGB). Since metabolic improvements after RYGB are clear, a better understanding of adipose tissue molecular modifications could be derived from this study. Thus, the aim of this systematic review was to find differentially expressed genes in subcutaneous adipose tissue of lean, obese and post-RYGB (distinct timepoints). To address this objective, publications from 2015-2022 reporting gene expression (candidate genes or transcriptomic approach) of subcutaneous adipose tissue from lean and obese individuals before and after RGYB were searched in PubMed, Elsevier, and Springer Link. Excluded publications were reviews, studies analyzing serum, other types of tissues, or bariatric procedures. A risk-of-bias summary was created for each paper using Robvis, to finally include 17 studies. Differentially expressed genes in post-RYGB vs. obese and lean vs. obese were obtained and the intersection among these groups was used for analysis and gene classification by metabolic pathway. Results showed that the lean state as well as the post-RYGB is similar in terms of increased expression of insulin-sensitizing molecules, inducing lipogenesis over lipolysis and downregulating leukocyte activation, cytokine production and other factors that promote inflammation. Thus, massive weight loss and metabolic improvements after RYGB are accompanied by gene expression modifications reverting the "adipocyte dysfunction" phenomenon observed in obesity conditions.

The Sexual Dimorphism of Human Adipose Depots

The amount and the distribution of body fat exhibit trajectories that are sex- and human species-specific and both are determinants for health. The enhanced accumulation of fat in the truncal part of the body as a risk factor for cardiovascular and metabolic diseases is well supported by epidemiological studies. In addition, a possible independent protective role of the gluteofemoral fat compartment and of the brown adipose tissue is emerging. The present narrative review summarizes the current knowledge on sexual dimorphism in fat depot amount and repartition and consequences on cardiometabolic and reproductive health. The drivers of the sex differences and fat depot repartition, considered to be the results of complex interactions between sex determination pathways determined by the sex chromosome composition, genetic variability, sex hormones and the environment, are discussed. Finally, the inter- and intra-depot heterogeneity in adipocytes and progenitors, emphasized recently by unbiased large-scale approaches, is highlighted.

Anti-Adipogenic Effects of Salicortin from the Twigs of Weeping Willow (Salix pseudolasiogyne) in 3T3-L1 Cells

Salix pseudolasiogyne (Salicaceae), the “weeping willow,” has been used in traditional Korean medicine to treat pain and fever due to its high concentrations of salicylic acid and salicin. The present study investigated bioactive compounds from S. pseudolasiogyne twigs to discover bioactive natural products. Phytochemical investigation of the ethanol (EtOH) extract of S. pseudolasiogyne twigs followed by liquid chromatography–mass spectrometry (LC/MS)-based analysis led to the isolation of two salicin derivatives, salicortinol and salicortin, the structures of which were determined by interpretation of their NMR spectra and data from the LC/MS analysis. To the best of our knowledge, this is the first report of salicortinol isolated from S. pseudolasiogyne. The isolated compounds were evaluated for their anti-adipogenic effects in 3T3-L1 cells. Both salicortinol and salicortin were found to significantly inhibit adipocyte differentiation in 3T3-L1 cells. In particular, salicortin exhibited a strong inhibitory effect on lipid accumulation. Furthermore, salicortin inhibited the expression of lipogenic and adipogenic transcription factors, including FASN, FABP4, C/EBPα, C/EBPβ, and PPARγ, without inducing cytotoxicity. These results suggest that salicortin could be a potential therapeutic compound for the prevention or treatment of metabolic disorders such as obesity.

Intersections between adolescent fertility and obesity-pathways and research gaps focusing on Latin American populations

Latin America has notably elevated rates of adolescent fertility and obesity in women. Although numerous studies document associations between adolescent fertility and obesity across the life course, the pathways explaining their association are insufficiently theorized, especially regarding the factors in Latin America that may underpin both. Additionally, much of the existing research is from high-income countries, where fertility and obesity are trending down. In this paper, we review the various complex pathways linking adolescent fertility and obesity, highlighting research gaps and priorities, with a particular focus on Latin American populations. We carefully consider pregnancy's distinct impact on growth trajectories during the critical period of adolescence, as well as the cumulative effect that adolescent fertility may have over the life course. We also articulate a pathway through obesity as it may contribute to early puberty and thus, to adolescent fertility. If obesity is a cause of adolescent fertility, not a result of it, or if it is a mediator of early-life exposures to adulthood obesity, these are critical distinctions for policy aiming to prevent both obesity and early fertility. Research to better understand these pathways is essential for prevention efforts against obesity and undesired adolescent fertility in Latin America.

Sex-specific association between elective cesarean section and growth trajectories in preschool children: A prospective birth cohort study

Background

Elective cesarean section (ECS) primarily contributes to the rising cesarean section (CS) rate, and much attention has been attracted to its health consequences. The association between ECS and overweight and obesity in children has been controversial, and few studies distinguished ECS with medical indications from those without indications. Based on a large sample birth cohort, we aim to examine the association of ECS with or without medical indications on children's physical development by using repeated anthropometric data from birth to 6 years of age.

Methods

A total of 2304 mother-child pairs with complete data on delivery mode and children's anthropometric measurements were recruited from the Ma'anshan-Anhui Birth Cohort (MABC) in China. ECS was the main exposure in this study, and the primary outcomes were children's growth trajectories and early adiposity rebound (AR). Children's BMI trajectories were fitted by using group-based trajectory models and fractional polynomial mixed-effects models. The association between ECS and children's growth trajectories and early AR was performed using multiple logistic regression models.

Results

Among 2,304 mother-child pairs (1199 boys and 1105 girls), 1088 (47.2%) children were born by CS, including 61 (5.6%) emergency CS, 441 (40.5%) ECS with medical indications, and 586 (53.9%) ECS without medical indications. After adjusting for potential confounders, it was found that ECS with medical indications was associated with a "high level" of BMI trajectory (OR = 1.776; 95% CI: 1.010-3.123), and ECS without medical indications was associated with early AR (OR = 1.517; 95% CI: 1.123-2.050) in girls. In boys, we found that ECS without medical indications was unlikely to experience an accelerated growth trajectory (OR = 0.484; 95%CI: 0.244-0.959).

Conclusions

ECS may be related to girls' "high level" BMI trajectories and early AR. If causal, the findings will provide an evidence-based reference for early life interventions for childhood obesity.

Preterm birth and metabolic implications on later life: A narrative review focused on body composition

Preterm newborn infants are characterized by low body weight and lower fat mass at birth compared with full-term newborn neonates. Conversely, at term corrected age, body fat mass is more represented in preterm newborn infants, causing a predisposition to developing metabolic syndrome and cardiovascular diseases in later life with a different risk profile in men as compared with women. Postnatal growth is a complex change in anthropometric parameters and body composition. Both quantity and quality of growth are regulated by several factors such as fetal programming, early nutrition, and gut microbiota. Weight gain alone is not an optimal indicator of nutritional status as it does not accurately describe weight quality. The analysis of body composition represents a potentially useful tool to predict later metabolic and cardiovascular risk as it detects the quality of growth by differentiating between fat and lean mass. Longitudinal follow-up of preterm newborn infants could take advantage of body composition analysis in order to identify high-risk patients who apply early preventive strategies. This narrative review aimed to examine the state-of-the-art body composition among born preterm children, with a focus on those in the pre-school age group.

Maternal High-Fat Diet Programs White and Brown Adipose Tissues In Vivo in Mice, with Different Metabolic and Microbiota Patterns in Obesity-Susceptible or Obesity-Resistant Offspring

Maternal obesity causes metabolic dysfunction in the offspring, including dysbiosis, overeating, obesity, and type 2 diabetes. Early-life phases are fundamental for developing subcutaneous (SAT) and brown adipose tissues (BAT), handling energy excesses. Imaging of ¹⁸F-fluorodeoxyglucose by positron emission tomography (PET) and radiodensity by computerized tomography (CT) allows assessing adipose tissue (AT) whitening and browning in vivo and the underlying metabolic efficiency. Our aim was to examine these in vivo traits in SAT and BAT concerning gut microbiota composition in 1- and 6-month-old mice born to normal (NDoff) and high-fat diet-fed dams (HFDoff), accounting for body weight responses. We found low radiodensity (high lipids) in HFDoff SAT at 1 month, relating to an increased abundance of Dorea genus in the caecum and activation of the fatty acid biosynthetic pathway. Instead, low BAT radiodensity and glucose uptake were seen in adult HFDoff. Glucose was shifted in favor of BAT at 1 month and SAT at 6 months. In adults, unclassified Enterococcaceae and Rikenellaceae, and Bacillus genera were negatively related to BAT, whereas unclassified Clostridiales genera were related to SAT metabolism. Stratification of HFDoff based on weight-response, namely maternal induced obesity (MIO-HFDoff) or obesity-resistant (MIOR-HFDoff), showed sex dimorphism. Both subgroups were hyperphagic, but only obese mice had hyper-leptinemia and hyper-resistinemia, together with BAT dysfunction, whereas non-obese HFDoff had hyperglycemia and SAT hypermetabolism. In the caecum, unclassified Rikenellaceae (10-fold enrichment in MIO-HFDoff) and Clostridiales genera (4-fold deficiency in MIOR-HFDoff) were important discriminators of these two phenotypes. In conclusion, SAT whitening is an early abnormality in the offspring of HFD dams. In adult life, maternal HFD and the induced excessive food intake translates into a dimorphic phenotype involving SAT, BAT, and microbiota distinctively, reflecting maternal diet*sex interaction. This helps explain inter-individual variability in fetal programming and the higher rates of type 2 diabetes observed in adult women born to obese mothers, supporting personalized risk assessment, prevention, and treatment.

Isometric strength of upper limb muscles in youth using hand-held and hand-grip dynamometry

The present study aimed to determine the isometric strength profile of the upper limb muscles of children and adolescents between 7–15 years of age. Furthermore, to (a) identify the age at which differences in strength are observed between sexes; to (b) determine the age range at which significant progression of strength could be observed; and (c) identify the role of each muscle on the total upper limb strength. Cross-sectional study that evaluated the isometric strength of nine muscle groups of the upper limb of 243 Chilean children, split into 9 age groups, separated by 1-year intervals. For this, hand-held dynamometry and hand-grip dynamometry were used. A two-factor analysis of variance for the maximum isometric strength and a stepwise multiple linear regression analysis were performed. From 11 years of age, wrist flexors were the first muscle group that revealed a significant difference in isometric strength in favor of boys (P=0.0143). In boys, the narrowest and earliest age range in the progression of isometric strength was 10 to 12 years for wrist flexors (P=0.0392). Shoulder flexors was the main factor that explained the performance of the total upper limb strength (R²=0.742; P<0.001). The most progressive isometric strength development occurred from age 10 years in the ventral and distal muscles of the upper limb; and from this age the boys begin to present a greater isometric strength than girls. In addition, the isometric strength of shoulder flexors explained the higher total upper limb strength performance.

Correction of neonatal vitamin D status using 1000 IU vitamin D/d increased lean body mass by 12 months of age compared with 400 IU/d: a randomized controlled trial

BACKGROUND

Intrauterine exposure to maternal vitamin D status <50 nmol/L of serum 25-hydroxyvitamin D [25(OH)D] may adversely affect infant body composition. Whether postnatal interventions can reprogram for a leaner body phenotype is unknown.

OBJECTIVES

The primary objective was to test whether 1000 IU/d of supplemental vitamin D (compared with 400 IU/d) improves lean mass in infants born with serum 25(OH)D <50 nmol/L.

METHODS

Healthy, term, breastfed infants (Montréal, Canada, March 2016-2019) were assessed for serum 25(OH)D (immunoassay) 24-36 h postpartum. Infants with serum 25(OH)D <50nmol/L at 24-36 h were eligible for the trial and randomly assigned at baseline (1 mo postpartum) to 400 (29 males, 20 females) or 1000 IU/d (29 males, 20 females) of vitamin D until 12 mo. Infants (23 males, 18 females) with 25(OH)D ≥50 nmol/L (sufficient) formed a nonrandomized reference group provided 400 IU/d. Anthropometry, body composition (DXA), and serum 25(OH)D concentrations were measured at 1, 3, 6, and 12 mo.

RESULTS

At baseline, mean ± SD serum 25(OH)D concentrations in infants allocated to the 400 and 1000 IU/d vitamin D groups were 45.8 ± 14.1 and 47.6 ± 13.4, respectively; for the reference group it was 69.2 ± 16.4 nmol/L. Serum 25(OH)D concentration increased on average to ≥50 nmol/L in the trial groups at 3-12 mo. Lean mass varied differently between groups over time; at 12 mo it was higher in the 1000 IU/d vitamin D group than in the 400 IU/d group (mean ± SD: 7013 ± 904.6 compared with 6690.4 ± 1121.7 g, P = 0.0428), but not the reference group (mean ± SD: 6715.1 ± 784.6 g, P = 0.19). Whole-body fat mass was not different between the groups over time.

CONCLUSIONS

Vitamin D supplementation (400 or 1000 IU/d) during infancy readily corrects vitamin D status, whereas 1000 IU/d modestly increases lean mass by 12 mo. The long-term implications require further research. This trial was registered at clinicaltrials.gov as NCT02563015.

Associations of Cord Blood Lipids with Childhood Adiposity at the Age of Three Years: A Prospective Birth Cohort Study

We aimed to examine the associations between cord blood lipids and childhood adiposity and to investigate whether these associations vary across birth weight categories (small for gestational age (SGA), appropriate for gestational age (AGA) and large for gestational age (LGA)) in 1306 infants in the Born in Guangzhou Cohort Study, China. Adiposity outcomes at the age of three years included z-scores of weight-for-length/height (WFLZ), body mass index (BMIZ), subscapular (SSTZ) and triceps skinfold thickness (TSTZ), and the sum of skinfold thicknesses (SSFTZ). Cord blood triglycerides (TG) levels were negatively associated with WFLZ and BMIZ, whereas high density lipoprotein (HDL) levels were positively associated with WFLZ, BMIZ, TSTZ and SSFTZ. These associations were attenuated after adjustment for birth weight. Stratified analyses revealed that total cholesterol (TC) and low-density lipoprotein (LDL) levels were positively associated with childhood adiposity indicators among AGA infants but tended to be negatively associated with the adiposity indicators among LGA infants (p values for interaction <0.05). Furthermore, TG levels appeared to be positively associated with adiposity indicators among SGA infants but negatively associated with the outcomes among LGA infants (p values for interaction <0.05). Cord blood lipids levels might be associated with childhood adiposity, and these associations appear to differ across different birth weight categories. If confirmed in future studies, our findings suggest that individualized management plans might be warranted in preventing obesity.

Influence of adipose tissue immune dysfunction on childhood obesity

In recent decades, a dramatic rise has been observed in the prevalence of obesity in childhood and adolescence, along with an increase in fetal microsomia rates. The increased risk of obesity during this key period in development negatively affects the health of the individual later in life. Immune cells residing and recruited to white adipose tissue have been highlighted as important factors contributing to the pathogenesis of childhood obesity. Immune dysfunction in the context of obesity begins early in childhood, which is different from the pathological characteristics and influencing factors of adipose immunity in adults. Here, we explore the current understanding of the roles of childhood and early life events that result in high risks for obesity by influencing adipose tissue immune dysfunction under the pathological condition of obesity. Such knowledge will help in determining the mechanisms of childhood and early life obesity in efforts to ameliorate chronic inflammation-related metabolic diseases.

Newborn and elderly skin: two fragile skins at higher risk of pressure injury

Skin is a key organ maintaining internal homeostasis by performing many functions such as water loss prevention, body temperature regulation and protection from noxious substance absorption, microorganism intrusion and physical trauma. Skin ageing has been well studied and it is well known that physiological changes in the elderly result in higher skin fragility favouring the onset of skin diseases. For example, prolonged and/or high-intensity pressure may suppress local blood flow more easily, disturbing cell metabolism and inducing pressure injury (PI) formation. Pressure injuries (PIs) represent a significant problem worldwide and their prevalence remains too high. A higher PI prevalence is correlated with an elderly population. Newborn skin evolution has been less studied, but some data also report a higher PI prevalence in this population compared to older children, and several authors also consider this skin as physiologically fragile. In this review, we compare the characteristics of newborn and elderly skin in order to determine common features that may explain their fragility, especially regarding PI risk. We show that, despite differences in appearance, they share many common features leading to higher fragility to shear and pressure forces, not only at the structural level but also at the cellular and molecular level and in terms of physiology. Both newborn and elderly skin have: (i) a thinner epidermis; (ii) a thinner dermis containing a less-resistant collagen network, a higher collagen III:collagen I ratio and less elastin; (iii) a flatter dermal-epidermal junction (DEJ) with lower anchoring systems; and (iv) a thinner hypodermis, resulting in lower mechanical resistance to skin damage when pressure or shear forces are applied. At the molecular level, reduced expression of transforming growth factor β (TGFβ) and its receptor TGFβ receptor II (TβRII) is involved in the decreased production and/or increased degradation of various dermal extracellular matrix (ECM) components. Epidermal fragility also involves a higher skin pH which decreases the activity of key enzymes inducing ceramide deficiency and reduced barrier protection. This seems to be correlated with higher PI prevalence in some situations. Some data also suggest that stratum corneum (SC) dryness, which may disturb cell metabolism, also increases the risk of PI formation. Besides this structural fragility, several skin functions are also less efficient. Low applied pressures induce skin vessel vasodilation via a mechanism called pressure-induced vasodilation (PIV). Individuals lacking a normal PIV response show an early decrease in cutaneous blood flow in response to the application of very low pressures, reflecting vascular fragility of the skin that increases the risk of ulceration. Due to changes in endothelial function, skin PIV ability decreases during skin ageing, putting it at higher risk of PI formation. In newborns, some data lead us to hypothesize that the nitric oxide (NO) pathway is not fully functional at birth, which may partly explain the higher risk of PI formation in newborns. In the elderly, a lower PIV ability results from impaired functionality of skin innervation, in particular that of C-fibres which are involved in both touch and pain sensation and the PIV mechanism. In newborns, skin sensitivity differs from adults due to nerve system immaturity, but the role of this in PIV remains to be determined.

Urinary phthalate metabolite mixtures in pregnancy and fetal growth: Findings from the infant development and the environment study

BACKGROUND

Prenatal phthalate exposure has been linked to reductions in fetal growth in animal and laboratory studies, but epidemiologic evidence is equivocal.

OBJECTIVE

Examine the association between prenatal phthalate metabolite mixtures and fetal growth and evaluate whether that association is modified by fetal sex or omega-3 intake during pregnancy.

METHODS

Analyses included 604 singleton pregnancies from TIDES, a prospective pregnancy cohort with spot urine samples and questionnaires collected in each trimester. Pregnancy-averaged phthalate exposure estimates were calculated as the geometric means of specific-gravity corrected phthalate metabolites. Fetal growth outcomes included birthweight and length, and ultrasound-derived size and velocity of estimated fetal weight, femur length, abdominal and head circumferences in the second and third trimesters. We used a novel application of quantile g-computation to estimate the joint association between pregnancy-averaged phthalate exposure and fetal growth, and to examine effect modification of that association by infant sex or omega-3 intake during pregnancy.

RESULTS

There were few statistically significant differences in birth size and fetal growth by exposure. A one-quartile increase in the phthalate mixture was modestly associated with reduced birthweight(β [95% confidence interval)]: -54.6 [-128.9, 19.7] grams; p = 0.15) and length (-0.2 [-0.6, 0.2] centimeters; p = 0.40). A one-quartile increase in the phthalate mixture was associated with reduced birth length in males (-0.5 [-1.0, 0.0] centimeters) but not for females (0.1 [-0.2, 0.3] centimeters); interaction p = 0.05. The phthalate metabolite mixture was inversely associated with ultrasound-derived fetal growth among those with adequate omega-3 intake. For example, a one-quartile increase in the phthalate mixture was associated with reduced abdominal circumference in the third trimesters in those with adequate omega-3 intake (-3.3 [-6.8, 0.1] millimeters) but not those with inadequate omega-3 intake (1.8 [-0.8, 4.5] millimeters); interaction p = 0.01.

CONCLUSION

Prenatal phthalate exposure was not significantly associated with fetal growth outcomes, with some exceptions for certain subgroups.

Prenatal Phthalate Exposure and Child Weight and Adiposity from in Utero to 6 Years of Age

BACKGROUND

Prenatal phthalate exposure has been associated with lower birth weight but also higher weight in childhood. Few studies have examined weight or adiposity from birth to childhood and thus cannot assess growth trajectories associated with exposure.

OBJECTIVE

We assessed associations between maternal phthalate exposures in pregnancy and child weight and adiposity measured prenatally through childhood (3-6 years of age).

METHODS

Within The Infant Development and the Environment Study (TIDES), a prospective pregnancy cohort, we analyzed a panel of phthalate metabolites in urine collected at two visits from early and late gestation (N=780). We estimated average phthalate metabolite associations with child weight z-scores from ∼20wk gestation (estimated by ultrasound), birth, and 1, 3, 4, and 6 years of age using linear mixed-effects (LME) models. We also modeled associations with adiposity z-scores from birth (weight for length) and 1, 3, 4, and 6 years of age [body mass index (BMI)] using LME models.

RESULTS

For weight, we observed inverse associations between several phthalate metabolites and birth weight z-scores, but no associations were observed with postnatal weight z-scores in LME models. Regarding adiposity, we observed inverse associations between phthalate metabolites and weight-for-length z-scores at birth, but positive associations were observed with BMI z-scores at 3-4 years of age in LME models. For example, mono-ethyl phthalate was associated with a 0.17-unit decrease in birth weight-for-length z-score [95% confidence interval (CI): -0.29, -0.05] and a 0.18-unit increase in 4-years-of-age BMI z-score (95% CI: 0.04, 0.32).

DISCUSSION

We observed associations between prenatal exposure to phthalates and lower weight at birth but not at childhood follow-up visits. However, for adiposity, we observed an interesting pattern of association with low adiposity at delivery as well as high adiposity at 3-4 years of age. Although it is not clear from our results whether these associations occur within the same children, such a pattern of adiposity in early life has been linked to cardiometabolic disease in adulthood and deserves special attention as an outcome in the study of prenatal exposures in the developmental origins of health and disease. https://doi.org/10.1289/EHP10077.

A Mixture of Endocrine Disrupting Chemicals Associated with Lower Birth Weight in Children Induces Adipogenesis and DNA Methylation Changes in Human Mesenchymal Stem Cells

Endocrine Disrupting Chemicals (EDCs) are man-made compounds that alter functions of the endocrine system. Environmental mixtures of EDCs might have adverse effects on human health, even though their individual concentrations are below regulatory levels of concerns. However, studies identifying and experimentally testing adverse effects of real-life mixtures are scarce. In this study, we aimed at evaluating an epidemiologically identified EDC mixture in an experimental setting to delineate its cellular and epigenetic effects. The mixture was established using data from the Swedish Environmental Longitudinal Mother and child Asthma and allergy (SELMA) study where it was associated with lower birth weight, an early marker for prenatal metabolic programming. This mixture was then tested for its ability to change metabolic programming of human mesenchymal stem cells. In these cells, we assessed if the mixture induced adipogenesis and genome-wide DNA methylation changes. The mixture increased lipid droplet accumulation already at concentrations corresponding to levels measured in the pregnant women of the SELMA study. Furthermore, we identified differentially methylated regions in genes important for adipogenesis and thermogenesis. This study shows that a mixture reflecting human real-life exposure can induce molecular and cellular changes during development that could underlie adverse outcomes.

Postnatal exposure to ambient temperature and rapid weight gain among infants delivered at term gestations: a population-based cohort study

BACKGROUND

The global prevalence of childhood obesity has risen dramatically recently. Previous studies found an association between rapid infant weight gain and childhood overweight. Evidence suggests that exposure to high ambient air temperatures during prenatal life and during adulthood is associated with birthweight and obesity respectively.

OBJECTIVE

The objective of this study was to examine whether exposure to high ambient temperatures during infancy is associated with rapid infant weight gain in Israel.

METHODS

This is a population-based historical cohort study using data from the Israeli national public network of maternal and child health clinics between 2008 and 2013. We assessed exposure to ambient temperature in the first year of life using a high-resolution hybrid spatio-temporal model and calculated annual mean and minimum temperatures for each infant based on daily mean and minimum temperatures at the community clinic location. We defined rapid infant weight gain as a World Health Organization weight z-score difference >0.67 between birthweight and weight at age one year. We estimated these associations using log-linear and general additive models and adjusted for population group, district, maternal age, parental education, parity, sex, gestational age, birthweight, calendar year and calendar month of birth.

RESULTS

The study population included 217,310 singleton-term infants. Adjusted models demonstrated a positive association between ambient temperature exposure and rapid infant weight gain. Compared to the third quintile of minimum temperature, infants exposed to the first and second quintile had an adjusted relative risk of 0.98 (95% CI 0.96, 1.00) and 0.97 (95% CI 0.95, 0.98), respectively, while those exposed to the fourth and fifth quintiles had an adjusted relative risk of 1.06 (95% CI 1.04, 1.07) and 1.02 (95% CI 1.00, 1.04) respectively. The associations with mean temperature were similar but slightly weaker.

CONCLUSIONS

Exposure to higher ambient temperatures, of emerging importance in the climate change era, is associated with rapid infant weight gain in Israel. Future studies should use additional exposure, covariate, and outcome data to analyse the nature and the source of this association in more detail.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

Prenatal Exposure to Nonpersistent Chemical Mixtures and Fetal Growth: A Population-Based Study

BACKGROUND

Prenatal exposure to mixtures of nonpersistent chemicals is universal. Most studies examining these chemicals in association with fetal growth have been restricted to single exposure models, ignoring their potentially cumulative impact.

OBJECTIVE

We aimed to assess the association between prenatal exposure to a mixture of phthalates, bisphenols, and organophosphate (OP) pesticides and fetal measures of head circumference, femur length, and weight.

METHODS

Within the Generation R Study, a population-based cohort in Netherlands (n=776), urinary concentrations of 11 phthalate metabolites, 3 bisphenols, and 5 dialkylphosphate (DAP) metabolites were measured at <18, 18-25, and >25 weeks of gestation and averaged. Ultrasound measures of head circumference, femur length, and estimated fetal weight (EFW) were taken at 18-25 and >25 weeks of gestation, and measurements of head circumference, length, and weight were performed at delivery. We estimated the difference in each fetal measurement per quartile increase in all exposures within the mixture with quantile g-computation.

RESULTS

The average EFW at 18-25 wk and >25wk was 369 and 1,626g, respectively, and the average birth weight was 3,451g. Higher exposure was associated with smaller fetal and newborn growth parameters in a nonlinear fashion. At 18-25 wk, fetuses in the second, third, and fourth quartiles of exposure (Q2-Q4) had 26g [95% confidence intervals (CI):-38, -13], 35g (95% CI: -55, -15), and 27g (95% CI: -54, 1) lower EFW compared with those in the first quartile (Q1). A similar dose-response pattern was observed at >25wk, but all effect sizes were smaller, and no association was observed comparing Q4 to Q1. At birth, we observed no differences in weight between Q1-Q2 or Q1-Q3. However, fetuses in Q4 had 91g (95% CI: -258, 76) lower birth weight in comparison with those in Q1. Results observed at 18-25 and >25wk were similar for femur length; however, no differences were observed at birth. No associations were observed for head circumference.

DISCUSSION

Higher exposure to a mixture of phthalates, bisphenols, and OP pesticides was associated with lower EFW in the midpregnancy period. In late pregnancy, these differences were similar but less pronounced. At birth, the only associations observed appeared when comparing individuals from Q1 and Q4. This finding suggests that even low levels of exposure may be sufficient to influence growth in early pregnancy, whereas higher levels may be necessary to affect birth weight. Joint exposure to nonpersistent chemicals may adversely impact fetal growth, and because these exposures are widespread, this impact could be substantial. https://doi.org/10.1289/EHP9178.

Sex differences in adipose development in a hunter-gatherer population

OBJECTIVE

Humans are unusually sexually dimorphic in body composition, with adult females having on average nearly twice the fat mass as males. The development of adipose sex differences has been well characterized for children growing up in food-abundant environments, with less known about cross-cultural variation, particularly in populations without exposure to market foods, mechanized technologies, schooling, vaccination, or other medical interventions.

METHODS

To add to the existing cross-cultural data, we fit multiple growth curves to body composition and anthropometric data to describe adipose development for the Savanna Pumé, South American hunter-gatherers.

RESULTS

(1) Little evidence is found for an adiposity 'rebound' at the end of early childhood among either Savanna Pumé girls or boys. (2) Rather, fat deposition fluctuates during childhood, from age ~4 to ~9 years, with no appreciable accumulation until the onset of puberty, a pattern also observed among Congo Baka hunter-gatherers. (3) Body fat fluctuations are more pronounced for girls than boys. (4) The age of peak skeletal, weight, and adipose gains are staggered to a much greater extent among the Savanna Pumé compared to the National Health and Nutrition Examination Survey (NHANES III) reference, suggesting this is an important developmental strategy in lean populations.

CONCLUSION

Documenting growth patterns under diverse preindustrial energetic conditions provides an important baseline for understanding sex differences in body fat emerging today under food abundance.

Maturation of the Visceral (Gut-Adipose-Liver) Network in Response to the Weaning Reaction versus Adult Age and Impact of Maternal High-Fat Diet

Metabolic-associated fatty liver disease is a major cause of chronic pathologies, of which maternal obesity is a frequent risk factor. Gut wall and microbiota, visceral fat, and liver form a pre-systemic network for substrates and pro-inflammatory factors entering the body, undergoing accelerated maturation in early-life when the weaning reaction, i.e., a transitory inflammatory condition, affects lifelong health. We aimed to characterize organ metabolism in the above network, in relation to weaning reaction and maternal obesity. Weaning or 6-months-old offspring of high-fat-diet and normal-diet fed dams underwent in vivo imaging of pre-/post-systemic glucose uptake and tissue radiodensity in the liver, visceral fat, and intestine, a liver histology, and microbiota and metabolic pathway analyses. Weaning mice showed the dominance of gut Clostridia and Bacteroidia members, overexpressing pathways of tissue replication and inflammation; adulthood increased proneness to steatohepatitis, and Desulfovibrio and RF39 bacteria, and lipopolysaccharide, bile acid, glycosaminoglycan, and sphingolipid metabolic pathways. In vivo imaging could track organ maturation, liver inflammation, and protective responses. A maternal high-fat diet amplified the weaning reaction, elevating liver glucose uptake, triglyceride levels, and steatohepatitis susceptibility along the lifespan. The visceral network establishes a balance between metabolism and inflammation, with clear imaging biomarkers, and crucial modulation in the weaning time window.

Early Appearance of Epicardial Adipose Tissue through Human Development

Background: Epicardial adipose tissue (EAT) is a visceral fat depot with unique anatomic, biomolecular and genetic features. Due to its proximity to the coronary arteries and myocardium, dysfunctional EAT may contribute to the development and progression of cardiovascular and metabolic-related adiposity-based chronic diseases. The aim of this work was to describe, by morphological techniques, the early origin of EAT. Methods: EAT adipogenesis was studied in 41 embryos from 32 gestational days (GD) to 8 gestational weeks (GW) and in 23 fetuses until full term (from 9 to 36 GW). Results: This process comprises five stages. Stage 1 appears as mesenchyme at 33-35 GD. Stage 2 is characterized by angiogenesis at 42-45 GD. Stage 3 covers up to 34 GW with the appearance of small fibers in the extracellular matrix. Stage 4 is visible around the coronary arteries, as multilocular adipocytes in primitive fat lobules, and Stage 5 is present with unilocular adipocytes in the definitive fat lobules. EAT precursor tissue appears as early as the end of the first gestational month in the atrioventricular grooves. Unilocular adipocytes appear at the eighth gestational month. Conclusions: Due to its early origin, plasticity and clinical implications, factors such as maternal health and nutrition might influence EAT early development in consequence.

The clinical impact of maternal weight on offspring health: lights and shadows in breast milk metabolome

INTRODUCTION

Pre-pregnancy overweight and obesity, depending on maternal nutrition and metabolic state, can influence fetal, neonatal and long-term offspring health, regarding cardio-metabolic, respiratory, immunological and cognitive outcomes. Thus, maternal weight can act, through mechanisms that are not full understood, on the physiology and metabolism of some fetal organs and tissues, to adapt themselves to the intrauterine environment and nutritional reserves. These effects could occur by modulating gene expression, neonatal microbiome, and through breastfeeding.

AREAS COVERED

In this paper, we investigated the potential effects of metabolites found altered in breast milk (BM) of overweight/obese mothers, through an extensive review of metabolomics studies, and the potential short- and long-term clinical effects in the offspring, especially regarding overweight, glucose homeostasis, insulin resistance, oxidative stress, infections, immune processes, and neurodevelopment.

EXPERT OPINION

Metabolomics seems the ideal tool to investigate BM variation depending on maternal or fetal/neonatal factors. In particular, BM metabolome alterations according to maternal conditions were recently pointed out in cases of gestational diabetes, preeclampsia, intrauterine growth restriction and maternal overweight/obesity. In our opinion, even if BM is the food of choice in neonatal nutrition, the deepest comprehension of its composition in overweight/obese mothers could allow targeted supplementation, to improve offspring health and metabolic homeostasis.

Effect of Elective Cesarean Section on Children's Obesity From Birth to Adolescence: A Systematic Review and Meta-Analysis

BACKGROUND

Elective cesarean section (ECS) is the most common reason for the increasing cesarean section rate worldwide, and it is reported to be related to adverse short-term and long-term outcomes in both mothers and infants. Findings on the association between ECS and overweight and obesity in children are controversial in recent studies. Therefore, we conducted a systematic review and meta-analysis to examine the effect of ECS on offspring's overweight and obesity.

METHODS

PubMed, Science Direct, Web of Science, CNKI (China National Knowledge Infrastructure), Wanfang Database (in Chinese), and China Biology Medicine disc databases were searched using different combinations of three groups of keywords: "elective cesarean section," "overweight/obesity," and "children." Nine cohort studies and 11 independent risk estimates were finally identified.

RESULTS

We have observed significant association between ECS and children's obesity, the total pooled risk ratio (RR) being 1.10 (95% CI: 1.01-1.18; I ² = 32.4%). In subgroup analysis, ECS was found to be associated with the occurrence of obesity in preschoolers (RR = 1.12, 95% CI: 1.02-1.22; I ² = 16.8%). Furthermore, it revealed that ECS was related with the high risk of children's obesity where the rate of ECS exceeded 10%. No significant association was observed between ECS and children's overweight, and the RR was 1.12 (95% CI: 0.94-1.30; I ² = 55.6%).

CONCLUSIONS

Overall, it indicated that children born via ECS had an increased risk of later-life obesity. Given the global increase in childhood obesity, our findings would provide evidence-based reference for early life intervention on children's obesity.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021267211, identifier: CRD42021267211.

Pro-Inflammatory Diet Is Associated with Adiposity during Childhood and with Adipokines and Inflammatory Markers at 11 Years in Mexican Children

There is limited evidence about the inflammatory potential of diet in children. The aim of this study was to evaluate the association between the Children's Dietary Inflammatory Index (C-DII) from 5 to 11 years with adiposity and inflammatory biomarkers in Mexican children. We analyzed 726 children from a birth cohort study with complete dietary information and measurements to evaluate adiposity at 5, 7 and 11 y and 286 children with IL-6, hsCRP, leptin and adiponectin information at 11 y. C-DII trajectories were estimated using latent class linear mixed models. We used linear mixed models for adiposity and logistic and multinomial regression for biomarkers. In girls, each one-point increase in C-DII score was associated with greater adiposity (abdominal-circumference 0.41%, p = 0.03; skinfold-sum 1.76%, p = 0.01; and BMI Z-score 0.05, p = 0.01). At 11 y the C-DII was associated with greater leptin (34% ≥ 13.0 ng/mL, p = 0.03) and hsCRP concentrations (29% ≥ 3.00 mg/L, p = 0.06) and lower adiponectin/leptin ratio (75% < 2.45, p = 0.02). C-DII trajectory 3 in boys was associated with a 75.2% (p < 0.01) increase in leptin concentrations and a 37.9% decrease (p = 0.02) in the adiponectin/leptin ratio. This study suggests that the inflammatory potential of diet may influence adiposity in girls and the homeostasis of adipose tissue and chronic subclinical inflammation in 11-year-old children.