Session 7: Early nutrition and later health early developmental pathways of obesity and diabetes risk

Unhealthy weight among young children in the Middle East and North African region

OBJECTIVE

To understand early-life growth in the Middle East and North Africa (MENA) region, and how it has changed over time, we estimated the prevalence of wasting and overweight at ages under 5 years.

DESIGN

Cross-sectional data from twenty-nine Demographic and Health Surveys with direct anthropometric data and parent-reported demographic information were examined. The study utilised the WHO Child Growth Standards to classify overweight (weight-for-height z-score ≥ 2 sd above the median), wasting (weight-for-height z-score ≤ 2 sd below the median) and unhealthy weight defined as either wasting or overweight.

SETTING

Nationally representative for nine of the MENA countries (Armenia, Azerbaijan, Egypt, Jordan, Mauritania, Morocco, Tunisia, Turkey and Yemen).

PARTICIPANTS

Children under age 5 from nine MENA countries between 1987 and 2016 (n 155 961).

RESULTS

Across the region, at the most recent time point, between 7·3 and 23·6 % of children experienced unhealthy weight (Jordan - 7·3 %, Egypt -23·6 %); 1·7 and 16·6 % had wasting (Turkey, Yemen) and 2·0 and 15·0 % had overweight (Yemen, Egypt). Overweight was more common than wasting in all countries except Yemen and Mauritania. Between 1987 and 2016, the prevalence of unhealthy weight in the region increased (10·0-18·4 %) due to increases in both wasting and overweight. Boys had a higher prevalence of unhealthy weight than girls.

CONCLUSION

Undernutrition continues to be a problem in some countries in the MENA region, and overnutrition is emerging as a health concern in many countries in the region. Countries in the region must advance programmes that reduce undernutrition while not overlooking or inadvertently promoting overnutrition.

The impact of obesity epidemic on type 2 diabetes in children and adolescents: A systematic review and meta-analysis

AIM

To assess the impact of the obesity epidemic on type 2 diabetes (T2D), prediabetes and glycometabolic indices in children and adolescents.

METHODS

We searched four electronic databases (PubMed, Embase, Cochrane and Web of Science). Cross-sectional or cohort studies that reported on obesity and the prevalence of T2D or prediabetes in children and adolescents were reviewed. The study design, sample size and clinical outcomes were extracted from each study. The prevalence of T2D and prediabetes from the studies were pooled using meta-analysis methods.

RESULTS

Meta-analysis of 228184 participants showed that the prevalence of T2D was 1.3% (95% confidence interval (CI), 0.6-2.1%) in obese subjects, which was 13 times that in normal weight subjects (0.1%, 95% CI, 0.01-0.2%). The prevalence of prediabetes in obese subjects was 3 times that in normal subjects at 17.0% (13.0-22.0%) vs. 6.0% (0.01-11.0%). Moreover, BMI was positively correlated with the prevalence of T2D, prediabetes and glycometabolic indices in obese children and adolescents.

CONCLUSION

The pooled results confirm that obesity in children and adolescents leads to statistically significant increases in the prevalence of T2D and prediabetes and in glycometabolic indicator levels.

Longitudinal Associations between Intake of Fruit and Vegetables and Height Attainment from Preschool to School Entry

To examine associations between fruit and vegetable intake in young childhood and height attainment during preschool and at school entry. Data for this study was based on "The Healthy Start" primary intervention study, which included 635 obesity-prone children, (58% boys), from the greater Copenhagen area, with a mean (SD) age of 4.0 (1.1) years (age range 2-6 years) at baseline. In the current study, 553 children (57% boys) were included with information on dietary intake at baseline and height measured at baseline (preschool age), and 511 children (56.8% boys) with the height measured at school entry (~6 years old). Height was measured by trained health professionals during the intervention and by school nurses at school entry. Information on intakes of fruit and vegetables, separately and combined, was gathered with four-day dietary records reported by parents. Participants were grouped into tertiles for their intakes at baseline. Compared to boys with low consumption, those with a moderate and high intakes of fruit and vegetables (F&V) had a greater attained height at preschool of 1.3 cm (95% confidence interval (CI): 0.3; 2.3) and at school entry of 2.4 cm (95% CI: 0.8; 3.9) and 1.8 cm (95% CI: 0.2; 3.4), respectively, also after adjustment for differences in age, body mass index (BMI), and total energy intake. Additional adjustment for mid-parental height and parents' education did not alter the significant associations between moderate consumption of F&V and attained height at preschool and school entry. There was no association among girls. Our results showed that a moderate consumption of F&V was directly associated with higher attainment in height at preschool and school entry in boys. From a public health perspective, it should be prioritized to continue developing intervention programs to improve fruit and vegetable intake.

Differential effects of leptin administration on feeding and HPT axis function in early-life overfed adult rats

Early-life overfeeding (OF) disrupts neuroendocrine systems, energy homeostasis and food intake regulation inducing overeating and overweight in adults. Adult rats raised in small litters during lactation, display hyperphagia and overweight since weaning and exhibit a decrease in thyrotropin-releasing hormone (TRH) mRNA expression in hypothalamic paraventricular nucleus (PVN). This is counterintuitive because TRH expression should increase to activate the hypothalamic-pituitary-thyroid (HPT) axis and promote energy expenditure, thus, HPT axis seems inhibited in OF rats. Leptin, an adipocyte-synthesized hormone that stimulates hypothalamic TRH expression, enhances both TRH anorectic effects and HPT axis-induced metabolic rate. To evaluate hypothalamic resistance to the anorectic and HPT axis stimulatory actions of leptin, we injected leptin i.p. to ad libitum fed and to 48-h fasted adult control (reared in normal litters) and to small-litter reared (OF) male Wistar rats. Findings showed that HPT axis was still responsive to leptin, since PVN TRH mRNA levels, median eminence TRH release and T4 serum concentration increased in both, ad libitum and fasted OF rats after leptin administrations. Leptin was ineffective to reduce feeding of OF animals. By comparing leptin receptor (ObRb) expression changes between arcuate and PVN nuclei, we observed that arcuate ObRb was not modified in response to leptin administrations in OF rats, likely accounting for the differential effects in feeding and HPT axis function. Nevertheless, ObRb expression was modified by leptin in the PVN of OF rats to the same extent as controls; this supports the hormone's role as a therapeutic agent for early onset obesity in adults.

Obesity and abnormal glucose tolerance in the offspring of mothers with diabetes

PURPOSE OF REVIEW

Type 2 diabetes and obesity during childhood, puberty, and adulthood have become more common. This trend presents a global problem in terms of public health and health economics. Associations between intrauterine exposure to hyperglycemia, obesity, and abnormal glucose tolerance (AGT) in offspring have been reported in populations at high risk of diabetes such as Pima Indians, but these associations have not been established in other groups. In this review, we summarize the evidence on obesity and AGT in the offspring of mothers with diabetes.

RECENT FINDINGS

Although there are many reports indicating that the incidence of obesity or overweight is higher in the offspring of mothers with gestational diabetes, there is no consensus on whether maternal prepregnancy obesity has a larger impact than intrauterine exposure to hyperglycemia. While the risk of AGT or type 2 diabetes in the offspring of mothers with gestational diabetes is thought to increase after puberty, the incidence of AGT is elevated by the age of 7 years in the offspring of mothers with untreated gestational diabetes. Maternal gestational diabetes is a risk factor for AGT or type 2 diabetes independent of maternal prepregnancy BMI. When the offspring of women who had gestational diabetes and received therapeutic intervention in two randomized controlled studies were followed, the prevalence of obesity and impaired fasting glucose was lower in some 7-year-old girls, but the effect of maternal intervention was limited. The risk of obesity or overweight is higher in the offspring of mothers with type 1 diabetes, even after adjustment for maternal prepregnancy BMI. The risk of type 2 diabetes in such offspring is also higher. Although the offspring of mothers with type 2 diabetes are likely to be at high risk for type 2 diabetes, there are only limited reports supporting this hypothesis.

SUMMARY

Intrauterine exposure to hyperglycemia is associated with obesity and AGT among offspring. The present review suggests that these associations might depend on the type of maternal diabetes, that is, the timing and degree of exposure to hyperglycemia. There are only a small number of studies on the effect of therapeutic interventions for maternal diabetes on metabolism in the offspring.

Birth weight and risk of type 2 diabetes: A dose-response meta-analysis of cohort studies

The association between birth weight and type 2 diabetes mellitus has been debated for several decades. The objective of this systematic review and meta-analysis was to quantitatively clarify the association between birth weight and risk of type 2 diabetes mellitus based on cohort studies. We searched PubMed, Web of Science, and Embase databases for cohort study articles on the association between birth weight and risk of type 2 diabetes mellitus published up to 1 March 2018. Random effects of generalized least square regression models were used to estimate relative risk (RR). Restricted cubic splines were conducted to model the dose-response relationship. We included 21 studies (19 articles) involving 1 041 879 individuals and 35 699 cases of type 2 diabetes mellitus, with follow-up ranged from 6 to 47 years. We identified significant decreasing trend for the highest versus lowest category of birth weight for the association with type 2 diabetes mellitus risk: The risk was reduced by 35% (RR, 0.65; 95% confidence interval [CI], 0.53-0.81) and by 12% (RR 0.88; 95% CI, 0.85-0.91) per 500-g increment in birth weight. Our results showed a dose-response relationship between birth weight and diabetes risk, which was nonlinear (P_nonlinearity  < 0.001) and L-shaped. With increasing birth weight (<5000 g), the risk of type 2 diabetes mellitus decreased substantially. The association between birth weight and type 2 diabetes mellitus was curvilinear and L-shaped.

A Biopsychosocial Model of Sex Differences in Children's Eating Behaviors

The prevalence of obesity and eating disorders varies by sex, but the extent to which sex influences eating behaviors, especially in childhood, has received less attention. The purpose of this paper is to critically discuss the literature on sex differences in eating behavior in children and present new findings supporting the role of sex in child appetitive traits and neural responses to food cues. In children, the literature shows sex differences in food acceptance, food intake, appetitive traits, eating-related compensation, and eating speed. New analyses demonstrate that sex interacts with child weight status to differentially influence appetitive traits. Further, results from neuroimaging suggest that obesity in female children is positively related to neural reactivity to higher-energy-dense food cues in regions involved with contextual processing and object recognition, while the opposite was found in males. In addition to differences in how the brain processes information about food, other factors that may contribute to sex differences include parental feeding practices, societal emphasis on dieting, and peer influences. Future studies are needed to confirm these findings, as they may have implications for the development of effective intervention programs to improve dietary behaviors and prevent obesity.

Early overnutrition reduces Pdx1 expression and induces β cell failure in Swiss Webster mice

Childhood obesity and early rapid growth increase the risk for type 2 diabetes. Such early overnutrition can be modeled in mice by reducing litter size. We investigated the effects of early overnutrition and increased dietary fat intake on β cell function in Swiss Webster mice. On a moderate-fat diet, early overnutrition accelerated weight gain and induced hyperinsulinemia in pups. Early overnutrition males exhibited higher β cell mass but reduced islet insulin content and Pdx1 expression. Males had a high diabetes incidence that was increased by early overnutrition, characterized by a progressive increase in insulin secretion as well as β cell death, indicated by histological analysis and increased circulating miR-375 levels. Females maintained normoglycemia throughout life. High-fat diet (HFD) increased diabetes incidence in males, whereas low-fat diet was completely protective. This protective effect was abolished in early overnutrition males transiently exposed to HFD in early life. Although Swiss Webster mice are not known to be diabetes-prone, the high diabetes incidence suggests an underlying genetic susceptibility that can be induced by overnutrition and increased dietary fat intake in early life. Thus, the nutritional environment in early life may impact long-term β cell function and increase diabetes risk, particularly in genetically susceptible individuals.

Mode of infant feeding, eating behaviour and anthropometry in infants at 6-months of age born to obese women - a secondary analysis of the UPBEAT trial

BACKGROUND

Maternal obesity and rapid infant weight gain have been associated with increased risk of obesity in childhood. Breastfeeding is suggested to be protective against childhood obesity, but no previous study has addressed the potential benefit of breastfeeding as a preventive method of childhood obesity amongst obese women. The primary aim of this study was to assess the relationship between mode of feeding and body composition, growth and eating behaviours in 6-month-old infants of obese women who participated in UPBEAT; a multi-centre randomised controlled trial comparing a lifestyle intervention of diet and physical activity to standard care during pregnancy.

METHODS

Three hundred and fifty-three mother and infant pairs attended a 6-months postpartum follow-up visit, during which they completed the Baby-Eating Behaviour Questionnaire, a parent-reported psychometric measure of appetite traits. Measures of infant body composition were also undertaken. As there was no effect of the antenatal intervention on infant feeding and appetite the study was treated as a cohort. Using regression analyses, we examined relationships between: 1) mode of feeding and body composition and growth; 2) mode of feeding and eating behaviour and 3) eating behaviour and body composition.

RESULTS

Formula fed infants of obese women in comparison to those exclusively breastfed, demonstrated higher weight z-scores (mean difference 0.26; 95% confidence interval 0.01 to 0.52), higher rate of weight gain (0.04; 0.00 to 0.07) and greater catch-up growth (2.48; 1.31 to 4.71). There was also a lower enjoyment of food (p = 0.002) amongst formula fed infants, following adjustment for confounders. Independent of the mode of feeding, a measure of infant appetite was associated with sum of skinfold thicknesses (β 0.66; 95% CI 0.12 to 1.21), calculated body fat percentage (0.83; 0.15 to 1.52), weight z-scores (0.21; 0.06 to 0.36) and catch-up growth (odds ratio 1.98; 1.21 to 3.21).

CONCLUSIONS

In obese women, exclusive breastfeeding was protective against increasing weight z-scores and trajectories of weight gain in their 6-month old infants. Measures of general appetite in early infancy were associated with measures of adiposity, weight and catch up growth independent of cord blood leptin concentrations and mode of early feeding.

Hyperleptinemia in Neonatally Overfed Female Rats Does Not Dysregulate Feeding Circuitry

Neonatal overfeeding during the first weeks of life in male rats is associated with a disruption in the peripheral and central leptin systems. Neonatally overfed male rats have increased circulating leptin in the first 2 weeks of life, which corresponds to an increase in body weight compared to normally fed counterparts. These effects are associated with a short-term disruption in the connectivity of neuropeptide Y (NPY), agouti-related peptide (AgRP), and pro-opiomelanocortin (POMC) neurons within the regions of the hypothalamus responsible for control of energy balance and food intake. Female rats that are overfed during the first weeks of their life experience similar changes in circulating leptin levels as well as in their body weight. However, it has not yet been studied whether these metabolic changes are associated with the same central effects as observed in males. Here, we hypothesized that hyperleptinemia associated with neonatal overfeeding would lead to changes in central feeding circuitry in females as it does in males. We assessed hypothalamic NPY, AgRP, and POMC gene expression and immunoreactivity at 7, 12, or 14 days of age, as well as neuronal activation in response to exogenous leptin in neonatally overfed and control female rats. Neonatally overfed female rats were hyperleptinemic and were heavier than controls. However, these metabolic changes were not mirrored centrally by changes in hypothalamic NPY, AGRP, and POMC fiber density. These findings are suggestive of sex differences in the effects of neonatal overfeeding and of differences in the ability of the female and male central systems to respond to changes in the early life nutritional environment.

Dietary intakes in children born small for gestational age and appropriate for gestational age: A longitudinal study

Children born small for gestational age (SGA) have an increased risk of cardiovascular disease (CVD) and associated risk factors in later life; however, little is known about their dietary intakes. The objective of this study was to assess dietary intakes in SGA and appropriate for gestational age (AGA) at 3.5, 7, and 11 years. The Auckland Birthweight Collaborative Study is a longitudinal case-control study of children born at term (n = 871). Children were assessed at 3.5 (n = 550), 7 (n = 591), and 11 (n = 620) years of age. Diet was assessed using a 24-hr record-assisted recall. Reported dietary intakes were analyzed and compared with the Australian and New Zealand Nutrient Reference Values. Compared with AGA, median energy intakes were significantly lower in SGA at 3.5 years (4.2 MJ [IQR, 3.0 to 5.8] vs. 5.4 MJ [IQR, 3.9 to 6.5]; p < .0001) but not at 7 and 11 years. Inadequate dietary intakes of micronutrients were more prevalent among SGA at 3.5 years and 11 years of age. A large proportion of SGA and AGA children consumed more than the recommended amounts of saturated fats, sugars, and sodium. There was no association of dietary intake and socio-demographic factors. This study reveals that dietary intake in 3.5-year-old children born SGA is lower in energy and a variety of micronutrients compared with dietary intake in AGA. These intakes may however be appropriate given their BMI z-scores. High intakes of sodium, saturated fat, and sugars are a concern for all children in this cohort.

Cord blood leptin and gains in body weight and fat mass during infancy

OBJECTIVES

Low early-life leptin concentrations may promote faster weight gain in infancy. We aimed to examine the associations between cord blood leptin concentrations and changes in weight and body composition during infancy.

DESIGN AND METHODS

Serum leptin was measured at 15 weeks gestation, in umbilical cord blood collected at delivery and at 2 years in 334 children from the Cork Baseline Birth Cohort Study. Body composition was measured at 2 days and 2 months using air displacement plethysmography. Conditional change in weight standard deviation scores over a number of age intervals in the first 2 years and conditional change in fat mass index (FMI) and fat-free mass index (FFMI) (kg/(length)m(2)) between birth and 2 months were calculated and associations with cord blood leptin were examined using linear regression.

RESULTS

At birth, cord blood leptin was positively correlated with FMI (r = 0.48, P < 0.001) and showed a weaker correlation with FFMI (r = 0.12, P = 0.05). After adjustment for confounders, higher cord blood leptin (per ng/mL) was associated with slower conditional weight gain between birth and 2 months (β (95% CI): -0.024 (-0.035, -0.013), P < 0.001) but not over subsequent age intervals. Cord blood leptin was also inversely associated with conditional change in FMI (-0.021 (-0.034, -0.007, P = 0.003) but not FFMI between birth and 2 months.

CONCLUSIONS

These are the first data to show that associations between higher cord blood leptin and slower weight gain during infancy are driven by lower increases in adiposity, at least in early infancy.

IUGR prevents IGF-1 upregulation in juvenile male mice by perturbing postnatal IGF-1 chromatin remodeling

BACKGROUND

Intrauterine growth restriction (IUGR) offspring with rapid catch-up growth are at increased risk for early obesity especially in males. Persistent insulin-like growth factor-1 (IGF-1) reduction is an important risk factor. Using a mouse model of maternal hypertension-induced IUGR, we examined IGF-1 levels, promoter DNA methylation, and histone H3 covalent modifications at birth (D1). We additionally investigated whether prenatal perturbations could reset at preadolescence (D21).

METHODS

IUGR was induced via maternal thromboxane A2-analog infusion in mice.

RESULTS

IUGR uniformly decreased D1 IGF-1 mRNA and protein levels with reduced promoter 1 (P1) transcription and increased P1 DNA methylation. IUGR males also had increased H3K4ac at exon 5 and 3' distal UTR. At D21, IUGR males continued to have decreased IGF-1 levels, originating from both P1 and P2 with reduced 1A variant. IUGR males also had decreased activation mark of H3K4me3 at P1 compared with sham males. In contrast, D21 IUGR females normalized their IGF-1 levels, in association with an increased activation mark of H3K4me3 at P1 compared with sham females.

CONCLUSION

IUGR uniformly affected D1 hepatic IGF-1 epigenetic modifications in both sexes. However, at preadolescence, IUGR males are unable to correct for the prenatal reduction possibly due to a more perturbed IGF-1 chromatin structure.

Neonatal Body Composition: Measuring Lean Mass as a Tool to Guide Nutrition Management in the Neonate

Neonatal nutrition adequacy is often determined by infant weight gain. The aim of this review is to summarize what is currently known about neonatal body composition and the use of body composition as a measure for adequate neonatal nutrition. Unlike traditional anthropometric measures of height and weight, body composition measurements account for fat vs nonfat mass gains. This provides a more accurate picture of neonatal composition of weight gain. Providing adequate neonatal nutrition in the form of quantity and composition can be a challenge, especially when considering the delicate balance of providing adequate nutrition to preterm infants for catch-up growth. Monitoring weight gain as fat mass and nonfat mass while documenting dietary intake of fat, protein, and carbohydrate in formulas may help provide the medical community the tools to provide optimal nutrition for catch-up growth and for improved neurodevelopmental outcomes. Tracking body composition in term and preterm infants may also provide critical future information concerning the nutritional state of infants who go on to develop future disease such as obesity, hypertension, and hyperlipidemia as adolescents or adults.

Higher Alu methylation levels in catch-up growth in twenty-year-old offsprings

Alu elements and long interspersed element-1 (LINE-1 or L1) are two major human intersperse repetitive sequences. Lower Alu methylation, but not LINE-1, has been observed in blood cells of people in old age, and in menopausal women having lower bone mass and osteoporosis. Nevertheless, Alu methylation levels also vary among young individuals. Here, we explored phenotypes at birth that are associated with Alu methylation levels in young people. In 2010, 249 twenty-years-old volunteers whose mothers had participated in a study association between birth weight (BW) and nutrition during pregnancy in 1990, were invited to take part in our present study. In this study, the LINE-1 and Alu methylation levels and patterns were measured in peripheral mononuclear cells and correlated with various nutritional parameters during intrauterine and postnatal period of offspring. This included the amount of maternal intake during pregnancy, the mother’s weight gain during pregnancy, birth weight, birth length, and the rate of weight gain in the first year of life. Catch-up growth (CUG) was defined when weight during the first year was >0.67 of the standard score, according to WHO data. No association with LINE-1 methylation was identified. The mean level of Alu methylation in the CUG group was significantly higher than those non-CUG (39.61% and 33.66 % respectively, P < 0.0001). The positive correlation between the history of CUG in the first year and higher Alu methylation indicates the role of Alu methylation, not only in aging cells, but also in the human growth process. Moreover, here is the first study that demonstrated the association between a phenotype during the newborn period and intersperse repetitive sequences methylation during young adulthood.

The pathogenic role of persistent milk signaling in mTORC1- and milk-microRNA-driven type 2 diabetes mellitus

Milk, the secretory product of the lactation genome, promotes growth of the newborn mammal. Milk delivers insulinotropic amino acids, thus maintains a molecular crosstalk with the pancreatic β-cell of the milk recipient. Homeostasis of β-cells and insulin production depend on the appropriate magnitude of mTORC1 signaling. mTORC1 is activated by branched-chain amino acids (BCAAs), glutamine, and palmitic acid, abundant nutrient signals of cow´s milk. Furthermore, milk delivers bioactive exosomal microRNAs. After milk consumption, bovine microRNA-29b, a member of the diabetogenic microRNA-29- family, reaches the systemic circulation and the cells of the milk consumer. MicroRNA-29b downregulates branchedchain α-ketoacid dehydrogenase, a potential explanation for increased BCAA serum levels, the metabolic signature of insulin resistance and type 2 diabetes mellitus (T2DM). In non-obese diabetic mice, microRNA-29b downregulates the antiapoptotic protein Mcl-1, which leads to early β-cell death. In all mammals except Neolithic humans, milk-driven mTORC1 signaling is physiologically restricted to the postnatal period. In contrast, chronic hyperactivated mTORC1 signaling has been associated with the development of age-related diseases of civilization including T2DM. Notably, chronic hyperactivation of mTORC1 enhances endoplasmic reticulum stress that promotes apoptosis. In fact, hyperactivated β-cell mTORC1 signaling induced early β-cell apoptosis in a mouse model. The EPIC-InterAct Study demonstrated an association between milk consumption and T2DM in France, Italy, United Kingdom, Germany, and Sweden. In contrast, fermented milk products and cheese exhibit an inverse correlation. Since the early 1950´s, refrigeration technology allowed widespread consumption of fresh pasteurized milk, which facilitates daily intake of bioactive bovine microRNAs. Persistent uptake of cow´s milk-derived microRNAs apparently transfers an overlooked epigenetic diabetogenic program that should not reach the human food chain.

The insulin-like growth factor I system: physiological and pathophysiological implication in cardiovascular diseases associated with metabolic syndrome

Metabolic syndrome is a cluster of risk factors including obesity, dyslipidemia, hypertension, and insulin resistance. A number of theories have been speculated for the pathogenesis of metabolic syndrome including impaired glucose and lipid metabolism, lipotoxicity, oxidative stress, interrupted neurohormonal regulation and compromised intracellular Ca(2+) handling. Recent evidence has revealed that adults with severe growth hormone (GH) and insulin-like growth factor I (IGF-1) deficiency such as Laron syndrome display increased risk of stroke and cardiovascular diseases. IGF-1 signaling may regulate contractility, metabolism, hypertrophy, apoptosis, autophagy, stem cell regeneration and senescence in the heart to maintain cardiac homeostasis. An inverse relationship between plasma IGF-1 levels and prevalence of metabolic syndrome as well as associated cardiovascular complications has been identified, suggesting the clinical promises of IGF-1 analogues or IGF-1 receptor activation in the management of metabolic and cardiovascular diseases. However, the underlying pathophysiological mechanisms between IGF-1 and metabolic syndrome are still poorly understood. This mini-review will discuss the role of IGF-1 signaling cascade in the prevalence of metabolic syndrome in particular the susceptibility to overnutrition and sedentary life style-induced obesity, dyslipidemia, insulin resistance and other features of metabolic syndrome. Special attention will be dedicated in IGF-1-associated changes in cardiac responses in various metabolic syndrome components such as insulin resistance, obesity, hypertension and dyslipidemia. The potential risk of IGF-1 and IGF-1R stimulation such as tumorigenesis is discussed. Therapeutic promises of IGF-1 and IGF-1 analogues including mecasermin, mecasermin rinfabate and PEGylated IGF-1 will be discussed.

How growth due to infant nutrition influences obesity and later disease risk

Infant nutrition has a major impact on immediate outcomes and long-term health and later disease risks, such as obesity and related disorders, a phenomenon referred to as 'metabolic programming'. This review discusses the currently postulated hypotheses and mechanisms investigated by the EarlyNutrition project.

CONCLUSION

Rapid weight gain in the first 2 years of life, most notably mediated by diary protein, affects the insulin-like growth factor metabolic pathways. Epigenetic processes seem to play a role.

Taurine-induced insulin signalling improvement of obese malnourished mice is associated with redox balance and protein phosphatases activity modulation

BACKGROUND & AIMS

Obese protein malnourished mice display liver insulin resistance and taurine (TAU) seems to attenuate this effect. The association between early-life malnutrition and hepatic redox balance in diet-induced insulin resistance is unknown. We investigated TAU supplementation effects upon liver redox state and insulin signalling in obese protein malnourished mice.

METHODS

Weaned male C57BL-6 mice were fed a control (14% protein - C) or a protein-restricted diet (6% protein - R) for 6 weeks. Afterwards, mice received a high-fat diet (34% fat - HFD) for 8 weeks (CH - RH). Half of the HFD-mice were supplemented with TAU (5%) throughout the treatment (CHT - RHT). Body and tissues' weight, respiratory quotient (RQ), glucose tolerance and insulin sensitivity, hepatic oxidant and antioxidant markers and insulin cascade proteins were assessed.

RESULTS

Protein restriction leads to typical features whereas HFD was able to induce a catch-up growth in RH. HFD-groups showed higher energy intake and adiposity, lower energy expenditure and altered RQ. Glucose tolerance and insulin sensitivity were impaired in HFD-groups and TAU attenuated these effects. H2 O2 content was increased in CHT and RHT despite no differences in antioxidant enzymes and GSH concentration. AKT and PTEN phosphorylation were significantly increased in CHT but not in RHT.

CONCLUSION

Our data provide evidence for an association between TAU-induced improved glycaemic control because of PTEN inactivation and higher AKT phosphorylation. These effects seem to be related with altered hepatic redox balance in obese mice, and this effect is impaired by protein malnutrition.

Branched-chain amino acid requirements for enterally fed term neonates in the first month of life

BACKGROUND

Knowledge of essential amino acid requirements in infants is important because excessive intake of protein can lead to increased long-term morbidity such as obesity. A deficient intake may lead to suboptimal growth and impaired neurodevelopment. The current recommended branched-chain amino acid requirements in infants aged 0-1 mo are based on the amino acid content of human milk.

OBJECTIVE

We quantified the requirements for isoleucine, leucine, and valine for term neonates by using the indicator amino acid oxidation method with [1-(13)C]phenylalanine as the indicator.

DESIGN

Fully enterally fed term infants received randomly graded amounts of isoleucine (5-216 mg · kg(-1) · d(-1)), leucine (5-370 mg · kg(-1) · d(-1)), or valine (5-236 mg · kg(-1) · d(-1)) as part of an elemental formula. Data are expressed as means ± SDs.

RESULTS

Eighty-three Asian, term neonates (mean ± SD birth weight: 3.3 ± 0.4 kg; gestational age: 39.4 ± 1.3 wk) were studied at a postnatal age of 13 ± 5 d. Mean requirements for isoleucine, leucine, and valine (measured in boys only) were 105 mg · kg(-1) · d(-1) (r(2) = 0.61, P < 0.001), 140 mg · kg(-1) · d(-1) (r(2) = 0.26, P < 0.01), and 110 mg · kg(-1) · d(-1) (r(2) = 0.35, P = 0.001), respectively.

CONCLUSIONS

Current human milk-based recommendations for isoleucine and valine in term infants aged 0-1 mo are correct. However, the current recommendation for leucine (166 mg · kg(-1) · d(-1)) is higher than the mean requirement of 140 mg · kg(-1) · d(-1) that we determined in this study. This trial was registered at www.trialregister.nl as NTR1610.

Catch-up growth following intra-uterine growth-restriction programmes an insulin-resistant phenotype in adipose tissue

Background:

It is now widely accepted that the early-life nutritional environment is important in determining susceptibility to metabolic diseases. In particular, intra-uterine growth restriction followed by accelerated postnatal growth is associated with an increased risk of obesity, type-2 diabetes and other features of the metabolic syndrome. The mechanisms underlying these observations are not fully understood.

Aim:

Using a well-established maternal protein-restriction rodent model, our aim was to determine if exposure to mismatched nutrition in early-life programmes adipose tissue structure and function, and expression of key components of the insulin-signalling pathway.

Methods:

Offspring of dams fed a low-protein (8%) diet during pregnancy were suckled by control (20%)-fed dams to drive catch-up growth. This ‘recuperated' group was compared with offspring of dams fed a 20% protein diet during pregnancy and lactation (control group). Epididymal adipose tissue from 22-day and 3-month-old control and recuperated male rats was studied using histological analysis. Expression and phosphorylation of insulin-signalling proteins and gene expression were assessed by western blotting and reverse-transcriptase PCR, respectively.

Results:

Recuperated offspring at both ages had larger adipocytes (P<0.001). Fasting serum glucose, insulin and leptin levels were comparable between groups but increased with age. Recuperated offspring had reduced expression of IRS-1 (P<0.01) and PI3K p110β (P<0.001) in adipose tissue. In adult recuperated rats, Akt phosphorylation (P<0.01) and protein levels of Akt-2 (P<0.01) were also reduced. Messenger RNA expression levels of these proteins were not different, indicating a post-transcriptional effect.

Conclusion:

Early-life nutrition programmes alterations in adipocyte cell size and impairs the protein expression of several insulin-signalling proteins through post-transcriptional mechanisms. These indices may represent early markers of insulin resistance and metabolic disease risk.

Demographic and socioeconomic correlates of adiposity assessed with dual-energy X-ray absorptiometry in US children and adolescents

BACKGROUND

Associations between demographic-socioeconomic characteristics and childhood obesity are complex in the United States.

OBJECTIVE

We examined associations between demographic-socioeconomic characteristics (age, sex, race-ethnicity, family income, household size, and birthplace) and adiposity measured by dual-energy X-ray absorptiometry in US children.

DESIGN

Data were from 8-19-y-old US children enrolled in NHANES 2001-2004 (n = 5436). Adiposity was expressed as the fat mass index (FMI = fat mass/height(2); in kg/m(2)), percentage body fat (%BF), and prevalence of normal, overfat, and excess fat corresponding to %BF <25%, 25-29.9%, and ≥30% in boys and <30%, 30-34.9%, and ≥35% in girls, respectively. We used sex-specific linear and multinomial logistic regression models adjusted for demographic-socioeconomic factors.

RESULTS

The prevalence of excess fat was higher in Mexican American (36%) than in white (28%; P ≤ 0.10) and black (21%; P < 0.05) boys; higher in Mexican American (44%) than in white (36%; P ≤ 0.10) and black (35%; P < 0.05) girls; and higher in US-born (38%) than in foreign-born (29%; P ≤ 0.10) Mexican American boys. In boys, %BF was higher in Mexican Americans and lower in blacks than in whites (P < 0.05). Adiposity was negatively associated with family income in white boys and girls and in Mexican American girls (P < 0.05). Racial-ethnic disparities in adiposity persisted (P < 0.001) after control for demographic-socioeconomic factors available in NHANES. The R(2) for sex-specific models of %BF or FMI regressed on age, race-ethnicity, family income, household size, and birthplace ranged from 2% to 11%.

CONCLUSION

The association between demographic-socioeconomic factors and adiposity among US children varied substantially by age, sex, and race-ethnicity.

Metabolic programming of insulin action and secretion

Type 2 diabetes (T2D), also known as non-insulin dependent diabetes mellitus, arises as a consequence of peripheral insulin resistance in combination with an inability of pancreatic islet β-cells to secrete adequate amounts of insulin. It is widely recognized that the current environment (e.g. an unhealthy diet and sedentary lifestyle) contributes to this process. In recent years, however, the role of the early environment, particularly nutrition, has emerged as an important factor capable of influencing health and disease risk of an individual, including risk of T2D. The impact of early environment on glucose metabolism has been extensively studied. Compelling evidence from epidemiological studies and animal models suggests that early nutrition can affect insulin action as a mediator of glucose homeostasis in peripheral tissues and as an important regulator of appetite and body weight. The early environment can also affect β-cell mass and function, and hence insulin secretion. The molecular mechanisms underlying the relationship between a suboptimal early environment and impaired insulin action and secretion is thought to include epigenetic modifications of the foetal genome, oxidative stress and mitochondrial dysfunction.

Higher fasting plasma free fatty acid levels are associated with lower insulin secretion in children and adults and a higher incidence of type 2 diabetes

CONTEXT

There are limited data in humans on the association between fasting free fatty acid (FFA) levels and pancreatic β-cell function.

OBJECTIVE

Our objective was to examine this association in children and adults with normal glucose tolerance and to explore fasting FFA levels in relation to subsequent risk of impaired glucose tolerance (IGT) and type 2 diabetes (T2D).

DESIGN

We measured FFA, glucose, and insulin levels after an overnight fast and 30 min after an oral glucose load in 797 children aged 8 yr in the Avon Longitudinal Study of Parents and Children and 770 adults aged 44-71 yr in the Medical Research Council Ely Study. We calculated the homeostasis model assessment to estimate fasting insulin sensitivity, the insulinogenic index to estimate insulin secretion, and the disposition index to assess insulin secretion corrected for insulin sensitivity.

RESULTS

Higher fasting FFA levels were associated with lower insulin secretion in children (boys, P = 0.03; girls, P = 0.001) and adults (men, P = 0.03, women, P = 0.04). Associations with insulin sensitivity were more variable, but after adjustment for insulin sensitivity, higher fasting FFA levels remained associated with lower insulin secretion (disposition index). Compared with adults in the lowest tertile of fasting FFA levels, those in the middle and highest tertiles had a 3-fold higher incidence of IGT or T2D over the following 5-8 yr.

CONCLUSIONS

Higher fasting FFA levels were consistently associated with lower insulin secretion in children and adults with normal glucose tolerance. Furthermore, higher fasting FFA levels were prospectively associated with a greater risk of subsequent IGT and T2D.

Body composition in infants: evidence for developmental programming and techniques for measurement

The consequences of fetal growth retardation remain unclear, in part because they appear to vary between industrialized and developing countries. Data on body composition offer a new opportunity to investigate this issue, and may be of particular value in addressing the controversial role of nutrition in infancy, which has been proposed by some to boost survival, and by others to increase long-term risk of chronic diseases. The uncertainty regarding the effects of post-natal nutrition is presenting challenges to nutritional policy as many countries undergo the nutrition transition, whereby the nutritional status of individuals may shift within the life-course. A theoretical model, building on the thrifty phenotype hypothesis, is presented to clarify how body composition data can address this dilemma. Measurements of body composition can now be obtained in infants and children using several different technologies, indicating that large-scale studies can now be conducted to investigate objectively the association between early growth patterns and later health.

Continuous parenteral and enteral nutrition induces metabolic dysfunction in neonatal pigs

BACKGROUND

We previously showed that parenteral nutrition (PN) compared with formula feeding results in hepatic insulin resistance and steatosis in neonatal pigs. The current aim was to test whether the route of feeding (intravenous [IV] vs enteral) rather than other feeding modalities (diet, pattern) had contributed to the outcome.

METHODS

Neonatal pigs were fed enterally or parenterally for 14 days with 1 of 4 feeding modalities as follows: (1) enteral polymeric formula intermittently (FORM), (2) enteral elemental diet (ED) intermittently (IEN), (3) enteral ED continuously (CEN), and (4) parenteral ED continuously (PN). Subgroups of pigs underwent IV glucose tolerance tests (IVGTT) and hyperinsulinemic-euglycemic clamps (CLAMP). Following CLAMP, pigs were euthanized and tissues collected for further analysis.

RESULTS

Insulin secretion during IVGTT was significantly higher and glucose infusion rates during CLAMP were lower in CEN and PN than in FORM and IEN. Endogenous glucose production rate was suppressed to zero in all groups during CLAMP. In the fed state, plasma glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide (GLP)-1, and GLP-2 were different between feeding modalities. Insulin receptor phosphorylation in liver and muscle was decreased in IEN, CEN, and PN compared with FORM. Liver weight was highest in PN. Steatosis and myeloperoxidase (MPO) activity tended to be highest in PN and CEN. Enterally fed groups had higher plasma GLP-2 and jejunum weight compared with PN.

CONCLUSIONS

PN and enteral nutrition (EN) when given continuously as an elemental diet reduces insulin sensitivity and the secretion of key gut incretins. The intermittent vs continuous pattern of EN produced the optimal effect on metabolic function.

Genetic and environmental contributions to weight, height, and BMI from birth to 19 years of age: an international study of over 12,000 twin pairs

OBJECTIVE

To examine the genetic and environmental influences on variances in weight, height, and BMI, from birth through 19 years of age, in boys and girls from three continents.

DESIGN AND SETTINGS

Cross-sectional twin study. Data obtained from a total of 23 twin birth-cohorts from four countries: Canada, Sweden, Denmark, and Australia. Participants were Monozygotic (MZ) and dizygotic (DZ) (same- and opposite-sex) twin pairs with data available for both height and weight at a given age, from birth through 19 years of age. Approximately 24,036 children were included in the analyses.

RESULTS

Heritability for body weight, height, and BMI was low at birth (between 6.4 and 8.7% for boys, and between 4.8 and 7.9% for girls) but increased over time, accounting for close to half or more of the variance in body weight and BMI after 5 months of age in both sexes. Common environmental influences on all body measures were high at birth (between 74.1-85.9% in all measures for boys, and between 74.2 and 87.3% in all measures for girls) and markedly reduced over time. For body height, the effect of the common environment remained significant for a longer period during early childhood (up through 12 years of age). Sex-limitation of genetic and shared environmental effects was observed.

CONCLUSION

Genetics appear to play an increasingly important role in explaining the variation in weight, height, and BMI from early childhood to late adolescence, particularly in boys. Common environmental factors exert their strongest and most independent influence specifically in pre-adolescent years and more significantly in girls. These findings emphasize the need to target family and social environmental interventions in early childhood years, especially for females. As gene-environment correlation and interaction is likely, it is also necessary to identify the genetic variants that may predispose individuals to obesity.

Determinants of rapid weight gain during infancy: baseline results from the NOURISH randomised controlled trial

Background

Rapid weight gain in infancy is an important predictor of obesity in later childhood. Our aim was to determine which modifiable variables are associated with rapid weight gain in early life.

Methods

Subjects were healthy infants enrolled in NOURISH, a randomised, controlled trial evaluating an intervention to promote positive early feeding practices. This analysis used the birth and baseline data for NOURISH. Birthweight was collected from hospital records and infants were also weighed at baseline assessment when they were aged 4-7 months and before randomisation. Infant feeding practices and demographic variables were collected from the mother using a self administered questionnaire. Rapid weight gain was defined as an increase in weight-for-age Z-score (using WHO standards) above 0.67 SD from birth to baseline assessment, which is interpreted clinically as crossing centile lines on a growth chart. Variables associated with rapid weight gain were evaluated using a multivariable logistic regression model.

Results

Complete data were available for 612 infants (88% of the total sample recruited) with a mean (SD) age of 4.3 (1.0) months at baseline assessment. After adjusting for mother's age, smoking in pregnancy, BMI, and education and infant birthweight, age, gender and introduction of solid foods, the only two modifiable factors associated with rapid weight gain to attain statistical significance were formula feeding [OR = 1.72 (95%CI 1.01-2.94), P = 0.047] and feeding on schedule [OR = 2.29 (95%CI 1.14-4.61), P = 0.020]. Male gender and lower birthweight were non-modifiable factors associated with rapid weight gain.

Conclusions

This analysis supports the contention that there is an association between formula feeding, feeding to schedule and weight gain in the first months of life. Mechanisms may include the actual content of formula milk (e.g. higher protein intake) or differences in feeding styles, such as feeding to schedule, which increase the risk of overfeeding.

Trial Registration

Australian Clinical Trials Registry ACTRN12608000056392

Neonatal overfeeding induced by small litter rearing causes altered glucocorticoid metabolism in rats

Elevated glucocorticoid (GC) activity may be involved in the development of the metabolic syndrome. Tissue GC exposure is determined by the tissue-specific GC-activating enzyme 11β-hydroxysteriod dehydrogenase type 1 (11β-HSD1) and the GC-inactivating enzyme 5α-reductase type 1 (5αR1), as well as 5β-reductase (5βR). Our aim was to study the effects of neonatal overfeeding induced by small litter rearing on the expression of GC-regulating enzymes in adipose tissue and/or liver and on obesity-related metabolic disturbances during development. Male Sprague-Dawley rat pup litters were adjusted to litter sizes of three (small litters, SL) or ten (normal litters, NL) on postnatal day 3 and then given standard chow from postnatal week 3 onward (W3). Small litter rearing induced obesity, hyperinsulinemia, and higher circulating corticosterone in adults. 11β-HSD1 expression and enzyme activity in retroperitoneal, but not in epididymal, adipose tissue increased with postnatal time and peaked at W5/W6 in both groups before declining. From W8, 11β-HSD1 expression and enzyme activity levels in retroperitoneal fat persisted at significantly higher levels in SL compared to NL rats. Hepatic 11β-HSD1 enzyme activity in SL rats was elevated from W3 to W16 compared to NL rats. Hepatic 5αR1 and 5βR expression was higher in SL compared to NL rats after weaning until W6, whereupon expression decreased in the SL rats and remained similar to that in NL rats. In conclusion, small litter rearing in rats induced peripheral tissue-specific alterations in 11β-HSD1 expression and activity and 5αR1 and 5βR expression during puberty, which could contribute to elevated tissue-specific GC exposure and aggravate the development of metabolic dysregulation in adults.

Early postnatal changes of lipoprotein subclass profile in late preterm infants

BACKGROUND

Late preterm infants (LPIs; 34-37 gestational weeks at birth) have higher risk for several morbidities than do term infants (TIs). It has been suggested that a cholesterol and fatty acid supply may improve their outcomes. We investigated the lipoprotein subclass profile in LPIs to evaluate their early postnatal lipid metabolism.

METHODS

Eighty-one infants (25 LPIs, 56 TIs) were included. Cholesterol and triglyceride (TG) concentrations in 12 lipoprotein subclasses were measured at birth and at 1 month using HPLC.

RESULTS

In LPIs, the cord blood exhibited higher cholesterol concentrations in medium and large subclasses of very low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) compared to the values in TIs. During the first month of life, LPIs had greater increases in cholesterol concentrations of medium and large subclasses of VLDL than TIs, whereas postnatal increases in cholesterol concentrations of medium and large subclasses of LDL and HDL were smaller. TG concentrations were not different in each VLDL subclass at birth and at 1 month.

CONCLUSIONS

In LPIs, cord blood lipoprotein subclass profiles and the early postnatal change exhibited different, especially in cholesterol concentrations.

First-borns have a higher metabolic rate and carry a higher metabolic risk in young women attending a weight loss clinic

BACKGROUND

Birth order has been associated with variability in early life growth and subsequent obesity risk, but the consequent metabolic risks have not been assessed.

OBJECTIVE

To quantify the metabolic risk in young adulthood of being first-born relative to those born second or subsequently.

METHODS

Body composition, resting metabolic rate and metabolic risk were assessed in 383 women, aged 18-35 years, from a clinical setting in southern Italy.

RESULTS

First-borns had increased body mass index, adiposity and metabolic risk (p<0.05) and increased resting metabolic rate adjusted for fat-free mass (p<0.05) in the Italian women.

CONCLUSION

First-born status is associated with significantly elevated metabolic risk in a clinical population of overweight and obese young women attending a weight loss clinic. If these findings are confirmed in other studies, they may suggest that the prevalence of the metabolic syndrome worldwide may increase as a function of the trend to smaller family size.

Breast-feeding and later risk of CVD and obesity: evidence from randomised trials

The relationship between breast-feeding and later cardiovascular health has been investigated in randomised trials and observational studies. This review focuses on randomised control trials, regarded as the ‘gold standard’ in establishing causal relationships between interventions and outcomes. Since it is not ethical to randomise healthy term infants to be breast- or formula-fed, only two randomised control trials have examined effects of breast-feeding on later health. In one randomised control trial, preterm infants randomised to receive banked donor breast milk had significantly lower blood pressure (BP), more favourable plasma lipid profile and reduced leptin resistance at age of 13–15 years compared with those who were fed preterm formula; with a dose–response relationship between the proportion of human milk and later outcomes. In contrast, a cluster-randomised control trial of a breast-feeding promotion intervention in healthy term infants (Promotion of Breast-feeding Intervention Trial study) found no effect of the intervention on adiposity or BP at 6 years, despite increased incidence, duration and exclusivity of breast-feeding. Potential explanations for the discrepancy between the two studies include: (i) beneficial effects of breast milk on cardiovascular health might be confined to preterm infants; (ii) effects on cardiovascular outcomes may not manifest until adolescence, a concept supported by other studies; (iii) if the underlying mechanism for the effect of breast-feeding on later cardiovascular outcome is slower early growth; a concept supported by data from animal models, human observational studies and now experimental studies in human subjects; it is plausible that differences in early growth between groups in the Promotion of Breast-feeding Intervention Trial were insufficient to produce a detectable effect on these outcomes.

Defining overweight and obesity in pre-school children: IOTF reference or WHO standard?

Two international datasets are used to define overweight and obesity in pre-school children: the International Obesity Task Force (IOTF) reference and the WHO standard. This study compares the performance of the two datasets in defining overweight and obesity in 24-60 months old children. This was done by plotting the IOTF cut-offs against WHO curves and by comparing the prevalence of overweight and obesity, as defined by the IOTF reference and by the WHO standard, using 2001 data from the Czech Republic. The IOTF cut-off for overweight in 24-60 months old children goes from 1.7 to 1.1 z-scores on the WHO chart, and for obesity it shifts with age from 2.7 to 2.2 z-scores. As a consequence, at 5 years of age the prevalence of overweight in Czech girls is 3.4% using the WHO and 15.3% using the IOTF definition. These discrepancies are due to the choice of cut-offs and to the different criteria used to select the sample for the IOTF reference and the WHO standard. Research is urgently needed to identify, for the WHO standard, BMI cut-offs associated with an increased risk of overweight and obesity, and associated health outcomes later in life.

Chronic parenteral nutrition induces hepatic inflammation, steatosis, and insulin resistance in neonatal pigs

Prematurity and overfeeding in infants are associated with insulin resistance in childhood and may increase the risk of adult disease. Total parenteral nutrition (TPN) is a major source of infant nutritional support and may influence neonatal metabolic function. Our aim was to test the hypothesis that TPN induces increased adiposity and insulin resistance compared with enteral nutrition (EN) in neonatal pigs. Neonatal pigs were either fed enteral formula orally or i.v. administered a TPN mixture for 17 d; macronutrient intake was similar in both groups. During the 17-d period, we measured body composition by dual-energy X-ray absorptiometry scanning; fasting i.v. glucose tolerance tests (IVGTT) and hyperinsulinemic-euglycemic clamps (CLAMP) were performed to quantify insulin resistance. On d 17, tissue was collected after 1-h, low-dose CLAMP for tissue insulin signaling assays. TPN pigs gained less lean and more body fat and developed hepatic steatosis compared with EN pigs. After 7 and 13 d, IVGTT showed evidence of insulin resistance in the TPN compared with the EN group. Fasting plasma glucose and insulin also were higher in TPN pigs. CLAMP showed that insulin sensitivity was markedly lower in TPN pigs than in EN pigs. TPN also reduced the abundance of the insulin receptor, insulin receptor substrate 1, and phosphatidylinositol 3 kinase in skeletal muscle and liver and the proliferation of total pancreatic cells and β-cells. Hepatic proinflammatory genes as well as c-Jun-N-terminal kinase 1 phosphorylation, plasma interleukin 6, and tumor necrosis factor-α were all higher in TPN pigs than in EN pigs. The results demonstrate that chronic TPN induces a hepatic inflammatory response that is associated with significant insulin resistance, hepatic steatosis, and fat deposition compared with EN in neonatal pigs. Further studies are warranted to establish the mechanism of TPN-induced insulin resistance and hepatic metabolic dysfunction and whether there are persistent metabolic consequences of this lifesaving form of infant nutritional support.

Early life nutrition and metabolic programming

Research investigating the early programming of adult metabolic disease has in recent years provided much mechanistic insight into how the early environment impacts on long-term health. It includes studies addressing the roles of intrauterine nutrient availability, which is determined by maternal nutrition, maternal exposure to oxygen, toxic events, and infection; the placental interface; and also the early postnatal environment. This review will explore the epidemiological evidence for programming of metabolic disease and provide an overview of the various studies using animals to model metabolic phenotypic outcome. It will also discuss evidence for the proposed molecular mechanisms and the potential for intervention.

First-borns carry a higher metabolic risk in early adulthood: evidence from a prospective cohort study

BACKGROUND

Birth order has been associated with early growth variability and subsequent increased adiposity, but the consequent effects of increased fat mass on metabolic risk during adulthood have not been assessed. We aimed to quantify the metabolic risk in young adulthood of being first-born relative to those born second or subsequently.

METHODOLOGY AND PRINCIPAL FINDINGS

Body composition and metabolic risk were assessed in 2,249 men, aged 17-19 years, from a birth cohort in southern Brazil. Metabolic risk was assessed using a composite z-score integrating standardized measurements of blood pressure, total cholesterol, high density lipoprotein, triglycerides and fat mass. First-borns had lower birth weight z-score (Δ = -0.25, 95%CI -0.35, -0.15,p<0.001) but showed greater weight gain during infancy (change in weight z-score from birth to 20 months: Δ = 0.39, 95%CI 0.28-0.50, p<0.0001) and had greater mean height (Δ = 1.2 cm, 95%CI: 0.7-1.6, p<0.0001) and weight (Δ = 0.34 kg, 95%CI: 0.13-0.55, p<0.002) at 43 months. This greater weight and height tracked into early adulthood, with first-borns being significantly taller, heavier and with significantly higher fat mass than later-borns. The metabolic risk z-score was significantly higher in first-borns.

CONCLUSIONS/SIGNIFICANCE

First-born status is associated with significantly elevated adiposity and metabolic risk in young adult men in Brazil. Our results, linking cardiovascular risk with life history variables, suggest that metabolic risk may be associated with the worldwide trend to smaller family size and it may interact with changes in behavioural or environmental risk factors.

Neonatal and fetal exposure to trans-fatty acids retards early growth and adiposity while adversely affecting glucose in mice

Industrially produced trans-fatty acids (TFAs) consumed in Western diets are incorporated into maternal and fetal tissues and are passed linearly to offspring via breast milk. We hypothesized that TFA exposure in utero and during lactation in infants would promote obesity and poor glycemic control as compared with unmodified fatty acids. We further hypothesized that in utero exposure alone may program for these outcomes in adulthood. To test this hypothesis, we fed female C57/BL6 mice identical Western diets that differed only in cis- or trans-isomers of C18:1 and then aimed to determine whether maternal transfer of TFAs through pregnancy and lactation alters growth, body composition, and glucose metabolism. Mice were unexposed, exposed during pregnancy, during lactation, or throughout pregnancy and lactation to TFA. Body weight and composition (by computed tomography) and glucose metabolism were assessed at weaning and adulthood. Trans-fatty acid exposure through breast milk caused significant early growth retardation (P < .001) and higher fasting glucose (P = .01), but insulin sensitivity was not different. Elevated plasma insulin-like growth factor-1 in mice consuming TFA-enriched milk (P = .02) may contribute to later catch-up growth and leanness and preserved peripheral insulin sensitivity observed in these mice. Mice exposed to TFA in utero underwent rapid early neonatal growth with TFA-free breast milk and had significantly impaired insulin sensitivity (P < .05) and greater abdominal fat (P = .01). We conclude that very early catch-up growth resulted in impaired peripheral insulin sensitivity in this model of diet-related fetal and neonatal programming. Trans-fatty acid surprisingly retarded growth and adiposity while still adversely affecting glucose metabolism.

Family stress and BMI in young children

AIM

The aim of this study was to investigate if family stress and parental attachment style are associated with body mass index (BMI) in young children, and identify possible explanations.

METHODS

A cross-sectional survey with a two-stage design was used. Parents of 873 children participated. They completed a demographic questionnaire, the Swedish Parenthood Stress Questionnaire (SPSQ), the Relationship Questionnaire (RQ) and reported their children's television-viewing habits (as a marker of physical activity). Children's height, weight and BMI were obtained from a general population-based register, BASTA. Associations with over- and underweight in children were assessed using multiple logistic regression analysis.

RESULTS

Family stress indicated by SPSQ-score was associated with suboptimal BMI. Maternal, but not paternal, SPSQ-stress score was statistically significantly associated with overweight and underweight, with adjusted odds ratios (and 95% confidence interval) of 4.61 (3.11-6.84; p < 0.001) and 3.08 (1.64-5.81; p < 0.001) respectively. Associations between childhood BMI and parental attachment style were identified, but were not independent of maternal SPSQ-score.

CONCLUSION

Our findings support a role for family stress in development of both overweight and underweight among young children. This is likely to be attributed to behavioural mechanisms but a more direct metabolic influence of stress could also be involved.

Overweight and obesity in infants and pre-school children in the European Union: a review of existing data

The objective of this study was to synthesize available information on prevalence and time trends of overweight and obesity in pre-school children in the European Union. Retrieval and analysis or re-analysis of existing data were carried out. Data sources include WHO databases, Medline and Google, contact with authors of published and unpublished documents. Data were analysed using the International Obesity Task Force reference and cut-offs, and the WHO standard. Data were available from 18/27 countries. Comparisons were problematic because of different definitions and methods of data collection and analysis. The reported prevalence of overweight plus obesity at 4 years ranges from 11.8% in Romania (2004) to 32.3% in Spain (1998-2000). Countries in the Mediterranean region and the British islands report higher rates than those in middle, northern and eastern Europe. Rates are generally higher in girls than in boys. With the possible exception of England, there was no obvious trend towards increasing prevalence in the past 20-30 years in the five countries with data. The use of the WHO standard with cut-offs at 1, 2 and 3 standard deviations yields lower rates and removes gender differences. Data on overweight and obesity in pre-school children are scarce; their interpretation is difficult. Standard methods of surveillance, and research and policies on prevention and treatment, are urgently needed.

The Family Atherosclerosis Monitoring In earLY life (FAMILY) study: rationale, design, and baseline data of a study examining the early determinants of atherosclerosis

BACKGROUND

Complex interactions among genetic, epigenetic, and environmental exposures, further modified by a child's postnatal environment, underlie the relationship among maternal health, fetal growth, and the development of cardiovascular disease (CVD) risk factors in the child and disease in the adult. Few available studies consider the genetic and environmental influences of the family, beyond maternal health. The purpose of this study is to examine the fetal and early childhood family-based determinants for the development of adiposity, CVD risk factors, and atherosclerosis in childhood.

METHOD

A cohort of 850 children and their families (mother, father, eldest sibling) are being recruited during pregnancy to a prospective longitudinal study to investigate the relative contribution of (a) prenatal and postnatal determinants and (b) individual and family (maternal/paternal) determinants for the development of adiposity and CVD risk factors at 3, 5, and 10 years of age and carotid intima media thickness at 10 years.

IMPLICATIONS

The FAMILY study will advance understanding of the fetal and early childhood determinants for CVD development and will contribute to the design of primary prevention programs based on identification of the most important modifiable determinants for early childhood adiposity and CVD risk factor development.

Growth from birth to adulthood and abdominal obesity in a Brazilian birth cohort

Background:

Rapid weight gain in childhood may increase the risk of chronic adult diseases. Few studies have examined the effects of lifecourse weight gain on waist circumference (WC), hip circumference (HC), or waist-to-hip ratio (WHR).

Objective:

To evaluate the effects of birthweight and weight gain from birth to age 23 years on WC, HC, and WHR in young adults.

Design:

Population-based birth cohort study started in 1982. A sample of 856 individuals was examined in 2006. Conditional growth analyses were carried out with adjustment for confounders. WC and HC were also mutually adjusted.

Results:

Weight gains during all age ranges studied (birthweight, 0–2, 2–4, 4–15, 15–18/19, and 18/19–23 years) were positively associated with WC and HC in both sexes. These effects were strongest from 4 to 15 years range (β=5.0 cm for both circumferences). Proxies for visceral adipose tissue (WHR and WC adjusted for HC) were associated with weight gain after 2 years in females and after 4 years in males. Subcutaneous adipose and muscular tissues, assessed by HC adjusted for WC, were associated with birthweight and weight gain from 0 to 2 years in both sexes, and again with weight gains from 4 to 18 years in males and 4 to 15 years in females.

Conclusions:

Weight gains in utero and in the first 2 years had long-term effects on HC, but weight gain after age 4 years was strongly associated with WC. Weight gains up to age 2 years may reduce cardiovascular risk associated with adult fat patterns in a middle-income setting.

Effect of growth on cardiometabolic status at 4 y of age

BACKGROUND

Cardiovascular disease (CVD) risks are increasingly being diagnosed in children and track into adulthood. Growth is associated with CVD risk in adulthood; however, its contribution to CVD risks in children facing the obesity epidemic is unclear.

OBJECTIVE

The objective was to assess relations between growth from age 0 to 4 y and CVD status at 4 y in 323 Chilean children with normal birth weight.

DESIGN

From health records we obtained weight and height every 6 mo from age 0 to 3 y and calculated body mass index (BMI; weight/height(2)). At age 4 y, we measured height, waist circumference, insulin, glucose, and plasma lipids; infant feeding information was provided by the mothers. Outcomes were metabolic score (waist-to-height ratio + glucose + insulin + triglycerides - HDL-cholesterol z scores/5), total cholesterol (TC):HDL cholesterol, and homeostasis model of assessment of insulin resistance.

RESULTS

At 4 y, the prevalence of obesity was 13%. Changes in BMI, particularly from 6 to 24 mo, predicted a higher metabolic score (standardized regression coefficient = 0.29; 95% CI: 0.16, 0.42) but were unrelated to homeostasis model of assessment of insulin resistance and TC:HDL cholesterol. Height changes were not associated with CVD risks at the age of 4 y. Mode of infant feeding was unrelated to CVD status at 4 y; however, in children who were exclusively breastfed at 4 mo, an increase in BMI from 0 to 6 mo was positively associated with TC:HDL cholesterol at 4 y (standardized regression coefficient = 0.24; 95% CI: -0.02, 0.50), whereas in children who were partially or nonbreastfed at 4 mo, it was negatively associated with TC:HDL cholesterol at 4 y (standardized regression coefficient = -0.30; 95% CI: -0.52, -0.08).

CONCLUSION

In children with normal birth weight and a high prevalence of obesity at 4 y, changes in BMI after 6 mo predicted a higher overall CVD risk at 4 y.

Early nutrition and long-term health: a practical approach

Nutrition in early life, a critical period for human development, can have long-term effects on health in adulthood. Supporting evidence comes from epidemiological studies, animal models and experimental interventions in human subjects. The mechanism is proposed to operate through nutritional influences on growth. Substantial evidence now supports the hypothesis that 'accelerated' or too fast infant growth increases the propensity to the major components of the metabolic syndrome (glucose intolerance, obesity, raised blood pressure and dyslipidaemia), the clustering of risk factors that predispose to cardiovascular morbidity and mortality. The association between infant growth and these risk factors is strong, consistent, shows a dose-response effect and is biologically plausible. Moreover, experimental data from prospective randomised controlled trials strongly support a causal link between infant growth and later risk factors for atherosclerosis. Evidence that infant growth affects the development of atherosclerosis therefore suggests that the primary prevention of CVD should begin from as early as the first few months of life. The present review considers this evidence, the underlying mechanisms involved and its implications for public health.

Exercise prescription for overweight and obese women: pregnancy and postpartum

Once a low-risk pregnancy has been established, walking in combination with nutritional control may be effective in preventing excessive weight gain in overweight and obese women. Maternal exercise prescription should use the Frequency, Intensity, Time spent and Type of exercise principle, with a frequency of three to four sessions per week as ideal. Intensity based on a target heart-rate zone of 110 to 131 beats per minute for women 20 to 29 years of age and 108 to 127 beats per minute for women 30 to 39 years of age, coupled with use of the rating of perceived exertion scale and the "Talk Test" is suggested. Dieting and exercise together are most effective in reducing weight retention after childbirth and compliance may be improved by incorporating child-care and children into the exercise routine. After medical consultation, postpartum women should begin exercise slowly, starting from 15 minutes, and building to at least 150 minutes of aerobic activity per week, with this activity spread throughout the week.

Gender in childhood obesity: family environment, hormones, and genes

BACKGROUND

The prevalence of obesity among children in the United States represents a pool of latent morbidity. Though the prevalence of obesity has increased in both boys and girls, the causes and consequences differ between the sexes. Thus, interventions proposed to treat and prevent childhood obesity will need to account for these differences.

OBJECTIVE

This review examines gender differences in the presentation of obesity in children and describes environmental, hormonal, and genetic factors that contribute to observed gender differences.

METHODS

A search of peer-reviewed, published literature was performed with PubMed for articles published from January 1974 through October 2008. Search terms used were obesity, sex, gender, hormones, family environment, body composition, adiposity, and genes. Studies of children aged 0 to 18 years were included, and only articles published in English were reviewed for consideration. Articles that illustrated gender differences in either the presentation or underlying mechanisms of obesity in children were reviewed for content, and their bibliographies were used to identify other relevant literature.

RESULTS

Gender differences in childhood obesity have been understudied partially because of how we define the categories of overweight and obesity. Close examination of studies revealed that gender differences were common, both before and during puberty. Boys and girls differ in body composition, patterns of weight gain, hormone biology, and the susceptibility to certain social, ethnic, genetic, and environmental factors.

CONCLUSION

Our understanding of how gender differences in pediatric populations relate to the pathogenesis of obesity and the subsequent development of associated comorbid states is critical to developing and implementing both therapeutic and preventive interventions.

Can infant feeding choices modulate later obesity risk?

Since the concept of lasting programming effects on disease risk in human adults by the action of hormones, metabolites, and neurotransmitters during sensitive periods of early development was proposed >3 decades ago, ample supporting evidence has evolved from epidemiologic and experimental studies and clinical trials. For example, numerous studies have reported programming effects of infant feeding choices on later obesity. Three meta-analyses of observational studies found that obesity risk at school age was reduced by 15-25% with early breastfeeding compared with formula feeding. We proposed that breastfeeding protects against later obesity by reducing the occurrence of high weight gain in infancy and that one causative factor is the lower protein content of human milk compared with most infant formula (the early protein hypothesis). We are testing this hypothesis in the European Childhood Obesity Project, a double-blind, randomized clinical trial that includes >1000 infants in 5 countries (Belgium, Germany, Italy, Poland, and Spain). We randomly assigned healthy infants who were born at term to receive for the first year infant formula and follow-on formula with higher or lower protein contents, respectively. The follow-up data obtained at age 2 y indicate that feeding formula with reduced protein content normalizes early growth relative to a breastfed reference group and the new World Health Organization growth standard, which may furnish a significant long-term protection against later obesity. We conclude that infant feeding practice has a high potential for long-term health effects, and the results obtained should stimulate the review of recommendations and policies for infant formula composition.

Prenatal nutrition: a critical window of opportunity for mother and child

The prenatal period encompasses a critical window for future health and functioning of mother and child. Attention previously focused on undernutrition risk (i.e., in developing countries and famine conditions) shifted to mismatch between prenatal 'programming' by undernutrition and postnatal overconsumption (i.e., low birthweight vs rapid postnatal growth), now to overconsumption/overweight throughout the reproductive cycle and short- and long-term health risks, including obesity, diabetes, dyslipidemia and cardiovascular disease. Moreover, overconsumption/overweight do not guarantee adequacy of critical nutrients (i.e., against birth defects or for brain development). Multinutrient supplementation - including zinc, iodine, choline and long-chain polyunsaturated fatty acids, especially n-3 - may have advantages over single-nutrient supplements, for example, iron or folate. Future nutritional care for healthy in utero programming may necessitate individual assessment and follow-up, including preconception nutritional preparation, appropriate weight gain, metabolic balance and food-based regimens enhanced by key nutrient fortification and/or supplementation, warranting further research into nutritional optimization of pregnancy outcomes.

The initiatives and outcomes for cardiovascular risks that can be achieved through paediatric counselling

PURPOSE OF REVIEW

Atherosclerosis is a result of a lifelong process. Obesity is associated with increased serum levels of inflammatory markers in children and adolescents like in adults, promoting coronary heart disease risk in an increasing proportion of young adults. Dietary patterns have a central role in the development of coronary heart disease through effects on serum lipids and development of body fatness. It is the purpose of this review to describe progress in this field.

RECENT FINDINGS

The supervised counselling aiming at low saturated fat intake by children decreases serum total and low-density lipoprotein (LDL) cholesterol values significantly and keeps them at lower level through childhood. It is not associated with abnormal growth or defects in cognitive or pubertal development. Coronary heart disease risk factor levels measured in childhood markedly influence vascular function and structure.

SUMMARY

To diminish the risk of premature atherosclerosis, the prime target in counselling of young children and their parents should be a change in fat quality rather than fat quantity. However, to prevent obesity, excessive consumption of total fat and sucrose needs to be avoided. Early commencement of statin therapy in children and adolescents suffering from familial hypercholesterolemia is beneficial in prevention of vascular atherosclerosis.