Preweaning growth hormone treatment ameliorates adipose tissue insulin resistance and inflammation in adult male offspring following maternal undernutrition

The Modulatory Role of Growth Hormone in Inflammation and Macrophage Activation

Inflammation is a body's response to remove harmful stimuli and heal tissue damage, which is involved in various physiology and pathophysiology conditions. If dysregulated, inflammation may lead to significant negative impacts. Growth hormone (GH) has been shown responsible for not only body growth but also critical in the modulation of inflammation. In this review, we summarize the current clinical and animal studies about the complex and critical role of GH in inflammation. Briefly, GH excess or deficiency may lead to pathological inflammatory status. In inflammatory diseases, GH may serve as an inflammatory modulator to control the disease progression and promote disease resolution. The detailed mechanisms and signaling pathways of GH on inflammation, with a focus on the modulation of macrophage polarization, are carefully discussed with potential direction for future investigations.

Food addiction symptoms and metabolic changes in children and adolescents with the double burden of malnutrition

The double burden of malnutrition (DBM) has been described in many low-/middle-income countries. We investigated food addiction, thyroid hormones, leptin, the lipid/glucose profile and body composition in DBM children/adolescents. Subjects were allocated into groups according to nutritional status: control (C, n 28), weight excess (WE, n 23) and DBM (WE plus mild stunting, n 22). Both the DBM and WE groups showed higher mean insulin concentrations than the control (DBM = 57·95 (95 % CI 47·88, 70·14) pmol/l, WE = 74·41 (95 % CI 61·72, 89·80) pmol/l, C = 40·03 (95 % CI 34·04, 47·83) pmol/l, P < 0·001). WE and DBM showed more food addiction symptoms than the control (3·11 (95 % CI 2·33, 3·89), 3·41 (95 % CI 2·61, 4·20) and 1·66 (95 % CI 0·95, 2·37)). In DBM individuals, addiction symptoms were correlated with higher body fat and higher insulin and leptin levels. These data provide preliminary evidence consistent with the suggestion that DBM individuals have a persistent desire to eat, but further studies are required to confirm these results in a larger study. These hormonal changes and high body fat contribute to the development of diabetes in long term.

Molecular mechanisms governing offspring metabolic programming in rodent models of in utero stress

The results of different human epidemiological datasets provided the impetus to introduce the now commonly accepted theory coined as 'developmental programming', whereby the presence of a stressor during gestation predisposes the growing fetus to develop diseases, such as metabolic dysfunction in later postnatal life. However, in a clinical setting, human lifespan and inaccessibility to tissue for analysis are major limitations to study the molecular mechanisms governing developmental programming. Subsequently, studies using animal models have proved indispensable to the identification of key molecular pathways and epigenetic mechanisms that are dysregulated in metabolic organs of the fetus and adult programmed due to an adverse gestational environment. Rodents such as mice and rats are the most used experimental animals in the study of developmental programming. This review summarises the molecular pathways and epigenetic mechanisms influencing alterations in metabolic tissues of rodent offspring exposed to in utero stress and subsequently programmed for metabolic dysfunction. By comparing molecular mechanisms in a variety of rodent models of in utero stress, we hope to summarise common themes and pathways governing later metabolic dysfunction in the offspring whilst identifying reasons for incongruencies between models so to inform future work. With the continued use and refinement of such models of developmental programming, the scientific community may gain the knowledge required for the targeted treatment of metabolic diseases that have intrauterine origins.

Maternal undernutrition results in altered renal pro-inflammatory gene expression concomitant with hypertension in adult male offspring that is ameliorated following pre-weaning growth hormone treatment

An adverse early life environment is associated with increased cardiovascular disease in offspring. Work in animal models has shown that maternal undernutrition (UN) during pregnancy leads to hypertension in adult offspring, with effects thought to be mediated in part via altered renal function. We have previously shown that growth hormone (GH) treatment of UN offspring during the pre-weaning period can prevent the later development of cardiometabolic disorders. However, the mechanistic basis for these observations is not well defined. The present study examined the impact of GH treatment on renal inflammatory markers in adult male offspring as a potential mediator of these reversal effects. Female Sprague-Dawley rats were fed either a chow diet fed ad libitum (CON) or at 50% of CON intake (UN) during pregnancy. All dams were fed the chow diet ad libitum during lactation. CON and UN pups received saline (CON-S/UN-S) or GH (2.5 µg/g/day; CON-GH/UN-GH) from postnatal day 3 until weaning (p21). Post-weaning males were fed a standard chow diet for the remainder of the study (150 days). Histological analysis was performed to examine renal morphological characteristics, and gene expression of inflammatory and vascular markers were assessed. There was evidence of renal hypotrophy and reduced nephron number in the UN-S group. Tumour necrosis factor-α, monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecular-1 and vascular cell adhesion molecule-1 gene expression was increased in UN-S offspring and normalized in the UN-GH group. These findings indicate that pre-weaning GH treatment has the potential to normalize some of the adverse renal and cardiovascular sequelae that arise as a consequence of poor maternal nutrition.

Epigenetic Programming and Fetal Metabolic Programming

Fetal metabolic programming caused by the adverse intrauterine environment can induce metabolic syndrome in adult offspring. Adverse intrauterine environment introduces fetal long-term relatively irreversible changes in organs and metabolism, and thus causes fetal metabolic programming leading metabolic syndrome in adult offspring. Fetal metabolic programming of obesity and insulin resistance plays a key role in this process. The mechanism of fetal metabolic programming is still not very clear. It is suggested that epigenetic programming, also induced by the adverse intrauterine environment, is a critical underlying mechanism of fetal metabolic programming. Fetal epigenetic programming affects gene expression changes and cellular function through epigenetic modifications without DNA nucleotide sequence changes. Epigenetic modifications can be relatively stably retained and transmitted through mitosis and generations, and thereby induce the development of metabolic syndrome in adult offspring. This manuscript provides an overview of the critical role of epigenetic programming in fetal metabolic programming.

Impact of gestational low protein diet and postnatal bisphenol A exposure on chemically induced mammary carcinogenesis in female offspring rats

This study evaluated the effect of gestational low protein diet (LPD) and/or postnatal bisphenol A (BPA) exposure on mammary gland development and carcinogenesis in female offspring. Pregnant Sprague-Dawley rats were fed a normal protein diet (NPD, 17% protein) or LPD (6% protein). At weaning, female offspring were distributed in four groups (NPD, LPD, NPD + BPA, and LPD + BPA) and received vehicle or BPA in drinking water (0.1%), during postnatal day (PND) 21 to 51. On PND 51, some female offspring were euthanized or received a single dose of 7,12-dimethylbenzoanthracene (DMBA, 30 mg/kg, i.g.) and were euthanized on PND 250. On PND 51, neither gestational LPD nor postnatal BPA exposure, individually or in combination, significantly altered the development of mammary gland tree, mean number of terminal structures or estrogen receptor beta (ER-β), proliferating cell nuclear antigen (PCNA) or caspase-3 protein expression in the mammary tissue. A significant reduction in mammary epithelial area (%) was observed in both LPD groups and a significant increase in ER-α protein expression was detected only in LPD group. In LPD + BPA group was observed a significant increase in both fat pad area (%) and in mean number of mammary epithelial cells positive for progesterone receptor (PR). On PND 250, the groups that received BPA presented lower latency and higher tumor incidence and tumor multiplicity and LPD + BPA group more aggressive tumors. These findings suggest that postnatal BPA exposure associated with gestational LPD is able to induce morphological changes in the mammary gland and increase susceptibility to mammary carcinogenesis.

Maternal High-Fat and High-Salt Diets Have Differential Programming Effects on Metabolism in Adult Male Rat Offspring

Maternal high-fat or high-salt diets can independently program adverse cardiometabolic outcomes in offspring. However, there is a paucity of evidence examining their effects in combination on metabolic function in adult offspring. Female Sprague Dawley rats were randomly assigned to either: control (CD; 10% kcal from fat, 1% NaCl), high-salt (SD; 10% kcal from fat, 4% NaCl), high-fat (HF; 45% kcal from fat, 1% NaCl) or high-fat and salt (HFSD; 45% kcal from fat, 4% NaCl) diets 21 days prior to mating and throughout pregnancy and lactation. Male offspring were weaned onto a standard chow diet and were culled on postnatal day 130 for plasma and tissue collection. Adipocyte histology and adipose tissue, liver, and gut gene expression were examined in adult male offspring. HF offspring had significantly greater body weight, impaired insulin sensitivity and hyperleptinemia compared to CD offspring, but these increases were blunted in HFSD offspring. HF offspring had moderate adipocyte hypertrophy and increased expression of the pre-adipocyte marker Dlk1. There was a significant effect of maternal salt with increased hepatic expression of Dgat1 and Igfb2. Gut expression of inflammatory (Il1r1, Tnfα, Il6, and Il6r) and renin-angiotensin system (Agtr1a, Agtr1b) markers was significantly reduced in HFSD offspring compared to HF offspring. Therefore, salt mitigates some adverse offspring outcomes associated with a maternal HF diet, which may be mediated by altered adipose tissue morphology and gut inflammatory and renin-angiotensin regulation.

Utility of Small Animal Models of Developmental Programming

Any effective strategy to tackle the global obesity and rising noncommunicable disease epidemic requires an in-depth understanding of the mechanisms that underlie these conditions that manifest as a consequence of complex gene-environment interactions. In this context, it is now well established that alterations in the early life environment, including suboptimal nutrition, can result in an increased risk for a range of metabolic, cardiovascular, and behavioral disorders in later life, a process preferentially termed developmental programming. To date, most of the mechanistic knowledge around the processes underpinning development programming has been derived from preclinical research performed mostly, but not exclusively, in laboratory mouse and rat strains. This review will cover the utility of small animal models in developmental programming, the limitations of such models, and potential future directions that are required to fully maximize information derived from preclinical models in order to effectively translate to clinical use.

Manipulation of the Growth Hormone-Insulin-Like Growth Factor (GH-IGF) Axis: A Treatment Strategy to Reverse the Effects of Early Life Developmental Programming

Evidence from human clinical, epidemiological, and experimental animal models has clearly highlighted a link between the early life environment and an increased risk for a range of cardiometabolic disorders in later life. In particular, altered maternal nutrition, including both undernutrition and overnutrition, spanning exposure windows that cover the period from preconception through to early infancy, clearly highlight an increased risk for a range of disorders in offspring in later life. This process, preferentially termed “developmental programming” as part of the developmental origins of health and disease (DOHaD) framework, leads to phenotypic outcomes in offspring that closely resemble those of individuals with untreated growth hormone (GH) deficiency, including increased adiposity and cardiovascular disorders. As such, the use of GH as a potential intervention strategy to mitigate the effects of developmental malprogramming has received some attention in the DOHaD field. In particular, experimental animal models have shown that early GH treatment in the setting of poor maternal nutrition can partially rescue the programmed phenotype, albeit in a sex-specific manner. Although the mechanisms remain poorly defined, they include changes to endothelial function, an altered inflammasome, changes in adipogenesis and cardiovascular function, neuroendocrine effects, and changes in the epigenetic regulation of gene expression. Similarly, GH treatment to adult offspring, where an adverse metabolic phenotype is already manifest, has shown efficacy in reversing some of the metabolic disorders arising from a poor early life environment. Components of the GH-insulin-like growth factor (IGF)-IGF binding protein (GH-IGF-IGFBP) system, including insulin-like growth factor 1 (IGF-1), have also shown promise in ameliorating programmed metabolic disorders, potentially acting via epigenetic processes including changes in miRNA profiles and altered DNA methylation. However, as with the use of GH in the clinical setting of short stature and GH-deficiency, the benefits of treatment are also, in some cases, associated with potential unwanted side effects that need to be taken into account before effective translation as an intervention modality in the DOHaD context can be undertaken.

Animal models of maternal high fat diet exposure and effects on metabolism in offspring: a meta-regression analysis

Animal models of maternal high fat diet (HFD) demonstrate perturbed offspring metabolism although the effects differ markedly between models. We assessed studies investigating metabolic parameters in the offspring of HFD fed mothers to identify factors explaining these inter-study differences. A total of 171 papers were identified, which provided data from 6047 offspring. Data were extracted regarding body weight, adiposity, glucose homeostasis and lipidaemia. Information regarding the macronutrient content of diet, species, time point of exposure and gestational weight gain were collected and utilized in meta-regression models to explore predictive factors. Publication bias was assessed using Egger's regression test. Maternal HFD exposure did not affect offspring birthweight but increased weaning weight, final bodyweight, adiposity, triglyceridaemia, cholesterolaemia and insulinaemia in both female and male offspring. Hyperglycaemia was found in female offspring only. Meta-regression analysis identified lactational HFD exposure as a key moderator. The fat content of the diet did not correlate with any outcomes. There was evidence of significant publication bias for all outcomes except birthweight. Maternal HFD exposure was associated with perturbed metabolism in offspring but between studies was not accounted for by dietary constituents, species, strain or maternal gestational weight gain. Specific weaknesses in experimental design predispose many of the results to bias.

Effects of prenatal low protein and postnatal high fat diets on visceral adipose tissue macrophage phenotypes and IL-6 expression in Sprague Dawley rat offspring

Adipose tissue macrophages (ATM) are implicated in adipose tissue inflammation and obesity-related insulin resistance. Maternal low protein models result in fetal programming of obesity. The study aims to answer whether maternal undernutrition by protein restriction affects the ATM M1 or M2 phenotype under postnatal high fat diet in F1 offspring. Using a rat model of prenatal low protein (LP, 8% protein) diet followed by a postnatal high fat energy diet (HE, 45% fat) or low fat normal energy diet (NE, 10% fat) for 12 weeks, we investigated the effects of these diets on adiposity, programming of the offspring ATM phenotype, and the associated inflammatory response in adipose tissue. Fat mass in newborn and 12-week old LP fed offspring was lower than that of normal protein (20%; NP) fed offspring; however, the adipose tissue growth rate was higher compared to the NP fed offspring. While LP did not affect the number of CD68⁺ or CD206⁺ cells in adipose tissue of NE offspring, it attenuated the number of these cells in offspring fed HE. In offspring fed HE, LP offspring had a lower percentage of CD11c⁺CD206⁺ ATMs, whose abundancy was correlated with the size of the adipocytes. Noteworthy, similar to HE treatment, LP increased gene expression of IL-6 within ATMs. Two-way ANOVA showed an interaction of prenatal LP and postnatal HE on IL-6 and IL-1β transcription. Overall, both LP and HE diets impact ATM phenotype by affecting the ratio of CD11c⁺CD206⁺ ATMs and the expression of IL-6.

Preweaning GH Treatment Normalizes Body Growth Trajectory and Reverses Metabolic Dysregulation in Adult Offspring After Maternal Undernutrition

Maternal undernutrition (UN) results in growth disorders and metabolic dysfunction in offspring. Although dysregulation of the GH-IGF axis in offspring is a known consequence of maternal UN, little is known about the efficacy of GH treatment during the period of developmental plasticity on later growth and metabolic outcomes. The present study investigated the effect of preweaning GH treatment on growth, glucose metabolism, and the GH-IGF axis in adult male and female offspring after maternal UN. Female Sprague Dawley rats were fed either a chow diet ad libitum (control [CON]) or 50% of ad libitum (UN) throughout pregnancy. From postnatal day 3, CON and UN pups received either saline (CON-S and UN-S) or GH (2.5 μg/g·d CON-GH and UN-GH) daily throughout lactation. At weaning, male and female offspring were randomly selected from each litter and fed a standard chow diet for the remainder of the study. Preweaning GH treatment normalized maternal UN-induced alterations in postweaning growth trajectory and concomitant adiposity in offspring. Plasma leptin concentrations were increased in UN-S offspring and normalized in the UN-GH group. Hepatic GH receptor expression was significantly elevated in UN-S offspring and normalized with GH treatment. Hepatic IGF binding protein-2 gene expression and plasma IGF-1 to IGF binding protein-3 ratio was reduced in UN-S offspring and elevated with GH treatment. GH treatment during a critical developmental window prevented maternal UN-induced changes in postnatal growth patterns and related adiposity, suggesting that manipulation of the GH-IGF-1 axis in early development may represent a promising avenue to prevent adverse developmental programming effects in adulthood.

Maternal supplementation with conjugated linoleic acid in the setting of diet-induced obesity normalises the inflammatory phenotype in mothers and reverses metabolic dysfunction and impaired insulin sensitivity in offspring

Maternal consumption of a high-fat diet significantly impacts the fetal environment and predisposes offspring to obesity and metabolic dysfunction during adulthood. We examined the effects of a high-fat diet during pregnancy and lactation on metabolic and inflammatory profiles and whether maternal supplementation with the anti-inflammatory lipid conjugated linoleic acid (CLA) could have beneficial effects on mothers and offspring. Sprague-Dawley rats were fed a control (CD; 10% kcal from fat), CLA (CLA; 10% kcal from fat, 1% total fat as CLA), high-fat (HF; 45% kcal from fat) or high fat with CLA (HFCLA; 45% kcal from fat, 1% total fat as CLA) diet ad libitum 10days prior to and throughout gestation and lactation. Dams and offspring were culled at either late gestation (fetal day 20, F20) or early postweaning (postnatal day 24, P24). CLA, HF and HFCLA dams were heavier than CD throughout gestation. Plasma concentrations of proinflammatory cytokines interleukin-1β and tumour necrosis factor-α were elevated in HF dams, with restoration in HFCLA dams. Male and female fetuses from HF dams were smaller at F20 but displayed catch-up growth and impaired insulin sensitivity at P24, which was reversed in HFCLA offspring. HFCLA dams at P24 were protected from impaired insulin sensitivity as compared to HF dams. Maternal CLA supplementation normalised inflammation associated with consumption of a high-fat diet and reversed associated programming of metabolic dysfunction in offspring. This demonstrates that there are critical windows of developmental plasticity in which the effects of an adverse early-life environment can be reversed by maternal dietary interventions.

Developmental programming: the role of growth hormone

Developmental programming of the fetus has consequences for physiologic responses in the offspring as an adult and, more recently, is implicated in the expression of altered phenotypes of future generations. Some phenotypes, such as fertility, bone strength, and adiposity are highly relevant to food animal production and in utero factors that impinge on those traits are vital to understand. A key systemic regulatory hormone is growth hormone (GH), which has a developmental role in virtually all tissues and organs. This review catalogs the impact of GH on tissue programming and how perturbations early in development influence GH function.

Diet, behavior and immunity across the lifespan

It is increasingly appreciated that perinatal events can set an organism on a life-long trajectory for either health or disease, resilience or risk. One early life variable that has proven critical for optimal development is the nutritional environment in which the organism develops. Extensive research has documented the effects of both undernutrition and overnutrition, with strong links evident for an increased risk for obesity and metabolic disorders, as well as adverse mental health outcomes. Recent work has highlighted a critical role of the immune system, in linking diet with long term health and behavioral outcomes. The present review will summarize the recent literature regarding the interactions of diet, immunity, and behavior.

Conjugated linoleic Acid supplementation during pregnancy and lactation reduces maternal high-fat-diet-induced programming of early-onset puberty and hyperlipidemia in female rat offspring

A maternal high-fat (HF) diet during pregnancy and lactation can result in adverse metabolic and reproductive outcomes in female offspring independent of postnatal diet. Interventions during critical windows of developmental plasticity may prevent developmental programming in offspring. The effects of maternal supplementation with the anti-inflammatory lipid conjugated linoleic acid (CLA) on early-onset puberty, metabolic dysfunction, and estrous cycle dysfunction was assessed. Sprague-Dawley rats were randomly assigned to a purified control diet (CD; 10% kcal from fat), CD with CLA (CLA; 10% kcal from fat, 1% CLA), HF (45% kcal from fat) or HF with CLA (HFCLA; 45% kcal from fat, 1% CLA). Diets were fed ad libitum for 10 days prior to time mating and throughout gestation and lactation. Offspring plasma/tissues were taken at Day 24 (prepubertal) or Day 150 (adult). Puberty was assessed from Day 26 and estrous cycle from Day 128. Female offspring from HF mothers had lower birth weights but by Postnatal Day 24 had exhibited catch-up growth concomitant with increased fat mass, hyperleptinemia, and dyslipidemia. Maternal CLA supplementation reversed these effects. Early-onset puberty was only observed in HF offspring; this was reversed in HFCLA offspring. In adulthood, despite no evidence of glucose intolerance or altered insulin sensitivity, HF offspring displayed increased fat mass, dyslipidemia, disrupted estrous cyclicity. and hyperleptinemia; this was reversed by maternal CLA supplementation. Data presented in this study demonstrate the importance of diet in women of reproductive age and during pregnancy on reproductive and metabolic parameters in their offspring and that supplementation with CLA during critical windows of development may represent a therapeutic strategy in the prevention of early-life programming of metabolic and reproductive dysfunction.

Let-7 miRNA profiles are associated with the reversal of left ventricular hypertrophy and hypertension in adult male offspring from mothers undernourished during pregnancy after preweaning growth hormone treatment

Maternal undernutrition (UN) is known to cause cardiac hypertrophy, elevated blood pressure, and endothelial dysfunction in adult offspring. Maternal UN may also lead to disturbances in GH regulation in offspring. Because GH plays a key role in cardiac development, we used a model of maternal UN to examine the effects of neonatal GH treatment on cardiac hypertrophy, cardiac micro RNA (miRNA) profiles, and associated gene regulation in adult offspring. Female Sprague-Dawley rats were fed either a standard control diet (CON) or 50% of CON intake throughout pregnancy (UN). From neonatal day 3 until weaning (d 21), CON and UN pups received either saline (S) (CON-S, UN-S) or GH (2.5 μg/g·d) (CON-GH, UN-GH). Heart structure was determined by hematoxylin and eosin staining, and miRNA was isolated from cardiac tissue and miRNA expression analyzed using Cardiovascular miRNA gene Arrays (SABiosciences Ltd). Maternal UN caused marked increases in cardiac hypertrophy and left ventricular cardiomyocyte area, which were reversed by preweaning GH treatment. Systolic blood pressure was increased in UN-S groups and normalized in UN-GH groups (CON-S 121 ± 2 mmHg, CON-GH 115 ± 3 mm Hg, UN-S 146 ± 3 mmHg, and UN-GH 127 ± 2 mmHg). GH treatment during early development facilitated a reversal of pathological changes in offspring hearts caused by UN during pregnancy. Specific cardiac miRNA profiles were exhibited in response to maternal UN, accompanied by up-regulation of the lethal-7 (LET-7) miRNA family in GH-treated offspring. miRNA target analysis revealed a number of genes associated with inflammation and cardiovascular development, which may be involved in the altered cardiac function of these offspring. Up-regulation of the LET-7 family of miRNAs observed in GH groups may mediate the reversal of cardiac hypertrophy observed in adult offspring males of UN mothers.

The importance of early life in childhood obesity and related diseases: a report from the 2014 Gravida Strategic Summit

Obesity and its related non-communicable diseases (NCDs), such as type 2 diabetes, heart disease and cancer, impose huge burdens on society, particularly the healthcare system. Until recently, public health and policy were primarily focused on secondary prevention and treatment of NCDs. However, epidemiological and experimental evidence indicates that early-life exposures influence the risk of childhood obesity and related diseases later in life, and has now focused attention on the health of both mother and child. During pregnancy and the early neonatal period, individuals respond to their environment by establishing anatomical, physiological and biochemical trajectories that shape their future health. This period of developmental plasticity provides an early window of opportunity to mitigate the environmental insults that may increase an individual’s sensitivity to, or risk of, developing obesity or related diseases later in life. Although much investigation has already occurred in the area of Developmental Origins of Health and Disease research, the science itself is still in its infancy. It remains for researchers to tackle the important outstanding questions and translate their knowledge into workable solutions for the public good. The challenge, however, is to decide which areas to focus on. With these opportunities and challenges in mind, the 2014 Gravida Summit convened to examine how its early-life research program can determine which areas of research into mechanisms, biomarkers and interventions could contribute to the international research strategy to fight childhood obesity and its related diseases.

Maternal nutritional history modulates the hepatic IGF-IGFBP axis in adult male rat offspring

Alterations in early life nutrition lead to an increased risk of obesity and metabolic syndrome in offspring. We have shown that both relative maternal undernutrition (UN) and maternal obesity result in metabolic derangements in offspring, independent of the postnatal dietary environment. Since insulin-like growth factor binding protein 2 (IGFBP2) has been shown to be independently associated with obesity and diabetes risk, we examined the IGF-IGFBP axis in male rat offspring following either maternal UN or maternal obesity to explain possible common pathways in the development of metabolic disorders. Wistar rats were time-mated and fed either a control diet (CONT), 50 % of CONT (UN) or a high-fat (HF) diet throughout pregnancy. Male offspring were weaned onto a standard chow diet and blood and tissues were collected at postnatal day 160. Plasma and hepatic tissue samples were analysed for key players in the IGF-IGFBP system. Both maternal UN and HF resulted in increased fat mass, hyperinsulinemia, hyperleptinemia and altered blood lipid profiles in offspring compared to CONT. Circulating IGF-1 and IGFBP3 levels and hepatic mRNA expression of IGFBP1 and IGFBP2 were significantly decreased in UN and HF offspring compared to CONT. DNA methylation of the IGFBP2 promotor region was similar between maternal dietary groups. Although chaperone gene heat-shock protein 90 and hepatic IGFBP1 were significantly correlated in CONT offspring this effect was absent in both UN and HF offspring. In conclusion, this study is one of the first to directly compare two experimental models of developmental programming representing both ends of the maternal dietary spectrum. Our data suggest that two disparate nutritional models that elicit similar adverse metabolic phenotypes in offspring are characterised by common alterations in the IGF-IGFBP pathway.

An evolving scientific basis for the prevention and treatment of pediatric obesity

The 2013 Pennington Biomedical Research Center's Scientific Symposium focused on the treatment and management of pediatric obesity and was designed to (i) review recent scientific advances in the prevention, clinical treatment and management of pediatric obesity, (ii) integrate the latest published and unpublished findings and (iii) explore how these advances can be integrated into clinical and public health approaches. The symposium provided an overview of important new advances in the field, which led to several recommendations for incorporating the scientific evidence into practice. The science presented covered a range of topics related to pediatric obesity, including the role of genetic differences, epigenetic events influenced by in utero development, pre-pregnancy maternal obesity status, maternal nutrition and maternal weight gain on developmental programming of adiposity in offspring. Finally, the relative merits of a range of various behavioral approaches targeted at pediatric obesity were covered, together with the specific roles of pharmacotherapy and bariatric surgery in pediatric populations. In summary, pediatric obesity is a very challenging problem that is unprecedented in evolutionary terms; one which has the capacity to negate many of the health benefits that have contributed to the increased longevity observed in the developed world.

Early-life growth hormone treatment to offspring of undernourished mothers alters metabolic parameters in primary adipocytes in adulthood

Maternal undernutrition (UN) is associated with the development of obesity and metabolic complications in adult offspring. This study investigated the impact of preweaning growth hormone (GH) treatment on adipocyte functionality in adult male offspring. Sprague-Dawley rats were assigned either standard (C) or undernourished (UN) diet (50% ad libitum) throughout gestation. Postnatal day 3-21, male C/UN pups received either saline (CS, UNS) or GH (2.5 µg/g/d; CGH, UNGH) by subcutaneous injection. Primary adipocytes were isolated following the collagenase digestion of adipose tissue. Primary adipocytes from UN offspring had significantly increased the secretion of pro-inflammatory cytokines accompanied by increased cytokine/cytokine receptor expression. This correlated with increased TLR4/NF-κB signaling. While increased inflammatory potential was not observed in adipocytes derived from UNGH offspring, there was a clear alteration in the expression of genes relating to carbohydrate and lipid metabolism along with nutrient transporters. Overall, preweaning GH treatment alters detrimental patterns of development, which predispose UN offspring to obesity and insulin resistance.