Effects of maternal surgical weight loss in mothers on intergenerational transmission of obesity

Rising incidence and challenges of childhood diabetes. A mini review

Approximately 215,000 people younger than 20 yr of age, or 1 in 500 children and adolescents, had diabetes in the United States in 2010--and the incidence is rising. We still have insufficient knowledge about the precise mechanisms leading to the autoimmune mediated β-cell destruction in Type 1 diabetes, and the β-cell failure associated with insulin resistance in Type 2 diabetes. Long-term complications are similar: micro- and macrovascular disease occurs prematurely and presents an enormous burden on affected individuals, often as early as in middle age. In Type 1 diabetes, technological advances have clearly improved blood glucose management, but chronic peripheral over-insulinization remains a problem even with the most advanced systems. Thus, in Type 1 diabetes our research must focus on 1) finding the stimulus that ignites the immune response and 2) developing treatments that avoid hyperinsulinemia. In Type 2 diabetes in youth, the challenges start much earlier: most young patients do not even benefit from existing therapies due to non-compliance. Therefore, prevention of Type 2 diabetes and improvement of compliance, especially with non-pharmacological interventions, are the greatest challenges.

Can we modify the intrauterine environment to halt the intergenerational cycle of obesity?

Child obesity is a global epidemic whose development is rooted in complex and multi-factorial interactions. Once established, obesity is difficult to reverse and epidemiological, animal model, and experimental studies have provided strong evidence implicating the intrauterine environment in downstream obesity. This review focuses on the interplay between maternal obesity, gestational weight gain and lifestyle behaviours, which may act independently or in combination, to perpetuate the intergenerational cycle of obesity. The gestational period, is a crucial time of growth, development and physiological change in mother and child. This provides a window of opportunity for intervention via maternal nutrition and/or physical activity that may induce beneficial physiological alternations in the fetus that are mediated through favourable adaptations to in utero environmental stimuli. Evidence in the emerging field of epigenetics suggests that chronic, sub-clinical perturbations during pregnancy may affect fetal phenotype and long-term human data from ongoing randomized controlled trials will further aid in establishing the science behind ones predisposition to positive energy balance.

Clinical review: Regulation of food intake, energy balance, and body fat mass: implications for the pathogenesis and treatment of obesity

CONTEXT

Obesity has emerged as one of the leading medical challenges of the 21st century. The resistance of this disorder to effective, long-term treatment can be traced to the fact that body fat stores are subject to homeostatic regulation in obese individuals, just as in lean individuals. Because the growing obesity epidemic is linked to a substantial increase in daily energy intake, a key priority is to delineate how mechanisms governing food intake and body fat content are altered in an obesogenic environment.

EVIDENCE ACQUISITION

We considered all relevant published research and cited references that represented the highest quality evidence available. Where space permitted, primary references were cited.

EVIDENCE SYNTHESIS

The increase of energy intake that has fueled the U.S. obesity epidemic is linked to greater availability of highly rewarding/palatable and energy-dense food. Obesity occurs in genetically susceptible individuals and involves the biological defense of an elevated body fat mass, which may result in part from interactions between brain reward and homeostatic circuits. Inflammatory signaling, accumulation of lipid metabolites, or other mechanisms that impair hypothalamic neurons may also contribute to the development of obesity and offer a plausible mechanism to explain the biological defense of elevated body fat mass.

CONCLUSIONS

Despite steady research progress, mechanisms underlying the resistance to fat loss once obesity is established remain incompletely understood. Breakthroughs in this area may be required for the development of effective new obesity prevention and treatment strategies.

Severe obesity: the neglected epidemic

Severe obesity (SO) is increasing faster than obesity in adults and in children. Because it is associated with numerous comorbidities, SO accounts for more health care expenditures than any other medical condition. Furthermore, it is associated with poor pregnancy outcomes for mother, fetus, and infant and a high risk of offspring obesity carried into adulthood. Bariatric surgery is the treatment of choice for SO because nonoperative methods fail to provide medically significant durable weight loss and because it is both preventive and therapeutic. The number of operations has sharply increased globally, yet only a small fraction of eligible patients are referred for surgical treatment demonstrating the need for improved access, especially for those disproportionately affected by SO. The risks of surgery mandate careful postoperative long-term multidisciplinary follow-up care. Education is critical for truly informed consent and must continue postoperatively, especially for women with reproductive potential. Even so, surgical treatment of SO remains cost-effective compared to conventional nonoperative treatment, which also requires long-term care. Just as obesity affects all medical disciplines (from allergology and immunology to oncology, urology and women's health), so does postoperative management of bariatric surgery patients. We offer wide-ranging recommendations for policymakers and others to consider in addressing SO.

Pregnancy after bariatric surgery: a current view of maternal, obstetrical and perinatal challenges

With the increase in the number of bariatric surgeries being performed in women of childbearing age, physicians must have concerns regarding the safety of pregnancy after bariatric surgery. The aim of this review is to summarize the literature reporting on maternal, obstetrical and perinatal implications of pregnancy following BS.

METHODS

English, Spanish and Portuguese-language articles were identified in a PUBMED search from 2005 to February 2011 using the keywords for pregnancy and bariatric surgery or gastric bypass or gastric banding.

RESULTS

The studies show improved fertility and a reduced risk of gestational diabetes, pregnancy-induced hypertension and pre-eclampsia, macrosomia in pregnant women after bariatric surgery. The incidence of intrauterine growth restriction and small for gestational age are increased. No conclusions can be drawn concerning the risk for cesarean delivery and the best surgery-to-conception interval. Deficiencies in iron, vitamin A, vitamin B12, vitamin K, folate and calcium can result in maternal and fetal complications.

CONCLUSIONS

Pregnancy outcome of women who delivered after BS, as compared to obese populations, is better and safer and comparable to the general population. Close supervision before, during and after pregnancy following bariatric surgery and nutrient supplementation adapted to the patient's individual requirements can prevent nutrition-related complications and improve maternal and fetal health.

Maternal obesity and the early origins of childhood obesity: weighing up the benefits and costs of maternal weight loss in the periconceptional period for the offspring

There is a need to understand the separate or interdependent contributions of maternal prepregnancy BMI, gestational weight gain, glycaemic control, and macronutrient intake on the metabolic outcomes for the offspring. Experimental studies highlight that there may be separate influences of maternal obesity during the periconceptional period and late gestation on the adiposity of the offspring. While a period of dietary restriction in obese mothers may ablate the programming of obesity, it is associated with an activation of the stress axis in the offspring. Thus, maternal obesity may result in epigenetic changes which predict the need for efficient fat storage in postnatal life, while maternal weight loss may lead to epigenetic changes which predict later adversity. Thus, development of dietary interventions for obese mothers during the periconceptional period requires a greater evidence base which allows the effective weighing up of the metabolic benefits and costs for the offspring.

Maternal diabetes and perinatal programming

Alterations of the intrauterine and neonatal environment may predispose for disorders and diseases throughout later life (perinatal programming). Especially, hormones and nutrients are dose-dependent organizers of the developing organism. Studies in offspring of diabetic mothers (ODM) have paradigmatically contributed to the perception of this developmental principle and our understanding of causal mechanisms. Fetal and neonatal hyperinsulinism in consequence of materno-fetal hyperglycaemia is the pathognomic feature in ODM. Epidemiological, clinical, as well as experimental data indicate that both insulin and glucose, when occurring in elevated concentrations during perinatal life, may epigenetically program a predisposition for obesity and diabetes later on. Similar may occur due to pre- and neonatal overfeeding. From a clinical point of view, avoidance of materno-fetal overnutrition, universal diabetes screening in all pregnant women and adequate therapy of all forms of diabetes during pregnancy, as well as avoidance of neonatal overfeeding are therefore recommended. These measures might serve as causal approaches of a genuine prevention to the benefit of long-term offspring health.

Intergenerational cycle of obesity and diabetes: how can we reduce the burdens of these conditions on the health of future generations?

Prepregnancy overweight or obesity and excessive gestational weight gain have been associated with increased risk of maternal and neonatal complications. Moreover, offspring from obese women are more likely to develop obesity, diabetes mellitus, and cardiovascular diseases in their lifetime. Gestational diabetes mellitus (GDM) is one of the most common complications associated with obesity and appears to have a direct impact on the future metabolic health of the child. Fetal programming of metabolic function induced by obesity and GDM may have intergenerational effect and thus perpetuate the epidemic of cardiometabolic conditions. The present paper thus aims at discussing the impact of maternal obesity and GDM on the developmental programming of obesity and metabolic disorders in the offspring. The main interventions designed to reduce maternal obesity and GDM and their ability to break the vicious circle that perpetuates the transmission of obesity and metabolic conditions to the next generations are also addressed.

Metabolic effects of sleeve gastrectomy in female rat model of diet-induced obesity

BACKGROUND

Although women disproportionately undergo bariatric surgery, the rodent models investigating the mechanisms of bariatric surgery have been limited to males. Female rodent models can also potentially allow us to understand the effects of surgical intervention on future generations of offspring. Sleeve gastrectomy is an attractive weight loss procedure for reproductive-age female patients because it avoids the malabsorption associated with intestinal bypass. We sought to evaluate the effect of sleeve gastrectomy on young female rats with diet-induced obesity at the University of California, Los Angeles, David Geffen School of Medicine.

METHODS

Sprague-Dawley female rats were fed a 60% high-fat diet. At 12 weeks of age, the rats underwent either sleeve gastrectomy or sham surgery. The rats were killed 4 weeks after surgery. A chemistry panel was performed, and the serum adipokines and gut hormones were assayed. The homeostasis model assessment score was calculated. The liver histologic findings were graded for steatosis. The 2-sample t test was used to compare the results between the 2 groups.

RESULTS

Sleeve gastrectomy was associated with significant weight loss (5% ± 6% versus -4% ± 6%; P < .001), lower leptin levels (1.3 ± 1.2 versus 3.5 ± 2.3 ng/mL; P < .01), and higher adiponectin levels (.43 ± .19 versus .17 ± .14 ng/mL; P < .004) compared with the sham-operated rats. No significant differences were found in the fasting ghrelin levels. Furthermore, we did not observe evidence of insulin resistance or steatohepatitis after 11 weeks of high-fat diet. Despite these limitations, additional gender-specific studies are warranted given that most bariatric surgeries are performed in women.

CONCLUSION

Sleeve gastrectomy appears to result in weight loss and improvements in adiponectin and leptin by way of mechanisms independent of ghrelin levels in a female model of diet-induced obesity.

Body weight at developmental age in siblings born to mothers before and after surgically induced weight loss

BACKGROUND

To gain insight into the role of epigenetic factors in determining body weight in adolescence, we studied the body weight of siblings born to the same mother before and after biliopancreatic diversion (BPD) for obesity. The study was performed in a university hospital during a 20-year period.

METHODS

The siblings born before and after BPD were retrospectively rated by their mother as normal, overweight, or obese at 1, 6, and 12 years.

RESULTS

At 1 and 6 years, the body weight was rated as similar in the subsets. However, at 12 years of age, a greater percentage of those born before BPD were considered overweight (42% versus 33%) and obese (22% versus 3%; P <.009) than their counterparts born after BPD. Considering only the subjects aged 21-25 years at the study period, the body weight and body mass index in subjects born before BPD were greater (P <.02 and P <.012, respectively) than in those born after BPD (79.5 ± 16.5 kg versus 66.7 ± 11.8 kg, and 27.5 ± 3.9 kg/m(2) versus 23.4 ± 3.7 kg/m(2), respectively).

CONCLUSION

The results of the present study, in which the influences of the genetic pattern and environmental and educational factors were minimized, show that adolescents born to post-BPD mothers weigh less than their siblings born to the same mother before BPD when she was still obese. An insulin-resistant milieu during pregnancy could account for the greater body weight later in adolescence.

Evidence for the intra-uterine programming of adiposity in later life

AIM

Research in animals has shown that altering foetal nutrition by under-nourishing or over-nourishing the mother or rendering her diabetic or foetal exposure to glucocorticoids and toxins can programme obesity in later life. The increased adiposity is mediated by permanent changes in appetite, food choices, physical activity and energy metabolism. In humans, increased adiposity has been shown in people who experienced foetal under-nutrition due to maternal famine or over-nutrition due to maternal diabetes. Lower birth weight (a proxy for foetal under-nutrition) is associated with a reduced adult lean mass and increased intra-abdominal fat. Higher birth-weight caused by maternal diabetes is associated with increased total fat mass and obesity in later life. There is growing evidence that maternal obesity, without diabetes, is also a risk factor for obesity in the child, due to foetal over-nutrition effects. Maternal smoking is associated with an increased risk of obesity in the children, although a causal link has not been proven. Other foetal exposures associated with increased adiposity in animals include glucocorticoids and endocrine disruptors.

CONCLUSIONS

Reversing the current obesity epidemic will require greater attention to, and better understanding of, these inter-generational (mother-offspring) factors that programme body composition during early development.

Developmental programming in response to maternal overnutrition

Metabolic disorders have seen an increased prevalence in recent years in developed as well as developing countries. While it is clear lifestyle choices and habits have contributed to this epidemic, mounting evidence suggests the nutritional milieu during critical stages of development in early life can "program" individuals to develop the metabolic syndrome later in life. Extensive epidemiological data presents an association between maternal obesity and nutrition during pregnancy and offspring obesity, and a number of animal models have been established in order to uncover the underlying mechanisms contributing to the programming of physiological systems. It is hard to distinguish the causal factors due to the complex nature of the maternal-fetal relationship; however, in order to develop adequate prevention strategies it is vital to identify which maternal factor(s) - be it the diet, diet-induced obesity or weight gain - and at which time during early development instigate the programmed phenotype. Curtailing the onset of obesity at this early stage in life presents a promising avenue through which to stem the growing epidemic of obesity.

[Obesity and female reproduction]

Weight, fat mass and obesity have been shown to play a major role in female reproduction. Obese women have a greater risk than nonobese women of infertility and they fail to become pregnant in both natural and assisted conception cycles. This cannot be explained only by their lack of ovulation. There are several potential mechanisms. On one hand, the endometrium seems to be partially responsible for this low fecundity in obese women. On the other hand, the oocyte seems to be implied. In a model of obese mouse, maternal obesity prior to conception is associated with altered mitochondria in mouse oocytes and an increased generation of reactive oxygen species (ROS). Furthermore, compared with controls, obese mice have significantly more decreased embryonic IGF-IR staining, smaller fetuses and smaller pups. In this model, all weaned pups have been fed with a regular diet. At 13 weeks, pups delivered from obese mice were significantly larger, and these pups demonstrated early development of a metabolic-type syndrome. These findings suggest that maternal obesity has adverse effects as early as the oocyte and preimplantation embryo stages and that these effects may contribute to lasting morbidity in offspring, underscoring the importance of optimal maternal weight and nutrition before conception.

Bariatric surgery in obese adolescents

PURPOSE OF REVIEW

Bariatric surgery is gaining acceptance as an effective and well tolerated treatment of morbid obesity in adults yet experience in obese children is still lacking. The purpose of this review is to highlight recent findings in this exciting field and identify the knowledge gaps.

RECENT FINDINGS

One randomized controlled trial and several case series have been published in the last 2 years regarding bariatric surgery for obese adolescents. These studies demonstrate relative safety along with significant weight loss. In addition, the vast majority of obesity-related comorbidities are resolved following these procedures. Adverse psychological effects of these procedures are probably more common than those in adults and need to be addressed.

SUMMARY

These publications indicate that bariatric surgical procedures, mainly gastric banding and gastric bypass, when performed on the right patients by skilled surgeons along with the appropriate ancillary staff, show positive metabolic effects and are well tolerated. Precise patient selection criteria, choice of the procedure and the extent of the multidisciplinary preoperative and postoperative care, are yet to be defined.

Genetics and epigenetics of obesity

Obesity results from interactions between environmental and genetic factors. Despite a relatively high heritability of common, non-syndromic obesity (40-70%), the search for genetic variants contributing to susceptibility has been a challenging task. Genome wide association (GWA) studies have dramatically changed the pace of detection of common genetic susceptibility variants. To date, more than 40 genetic variants have been associated with obesity and fat distribution. However, since these variants do not fully explain the heritability of obesity, other forms of variation, such as epigenetics marks, must be considered. Epigenetic marks, or "imprinting", affect gene expression without actually changing the DNA sequence. Failures in imprinting are known to cause extreme forms of obesity (e.g. Prader-Willi syndrome), but have also been convincingly associated with susceptibility to obesity. Furthermore, environmental exposures during critical developmental periods can affect the profile of epigenetic marks and result in obesity. We review the most recent evidence for genetic and epigenetic mechanisms involved in the susceptibility and development of obesity. Only a comprehensive understanding of the underlying genetic and epigenetic mechanisms, and the metabolic processes they govern, will allow us to manage, and eventually prevent, obesity.

Developmental programming of energy balance and its hypothalamic regulation

Developmental programming is an important physiological process that allows different phenotypes to originate from a single genotype. Through plasticity in early life, the developing organism can adopt a phenotype (within the limits of its genetic background) that is best suited to its expected environment. In humans, together with the relative irreversibility of the phenomenon, the low predictive value of the fetal environment for later conditions in affluent countries makes it a potential contributor to the obesity epidemic of recent decades. Here, we review the current evidence for developmental programming of energy balance. For a proper understanding of the subject, knowledge about energy balance is indispensable. Therefore, we first present an overview of the major hypothalamic routes through which energy balance is regulated and their ontogeny. With this background, we then turn to the available evidence for programming of energy balance by the early nutritional environment, in both man and rodent models. A wealth of studies suggest that energy balance can indeed be permanently affected by the early-life environment. However, the direction of the effects of programming appears to vary considerably, both between and within different animal models. Because of these inconsistencies, a comprehensive picture is still elusive. More standardization between studies seems essential to reach veritable conclusions about the role of developmental programming in adult energy balance and obesity.

Long-term experience with duodenal switch in adolescents

BACKGROUND

Severe or extreme obesity in children and adolescents is a progressive damaging disease, increasingly requiring surgical treatment. Timing and choice of operation are controversial.

METHOD

In the last 16 years, we performed open biliopancreatic diversion with duodenal switch (DS) in 13 adolescents aged 15-17 years, who have been followed up for 2-16 years (mean, 10.6 years); three with Prader-Willi syndrome (PWS) are presented separately.

RESULTS

Among the ten non-PWS children (7 girls), no deaths or perioperative complications were reported, mean body mass index (BMI) decreased from 55.9 ± 14.0 to 28.8 ± 3.7 kg/m(2) (% excess weight loss (EWL) = 82.1 ± 10.5%), and none have regained weight. All comorbidities were cured except asthma, which improved in one patient. There were two reoperations: one for intestinal obstruction and one for post-anastomotic ulcer. Glucose and lipid metabolism improved, while vitamin and mineral deficiencies were mild and rare. Five of the seven girls gave birth to 11 children, aged 2-12 years, two of whom are overweight but not severely obese. Neurodevelopment is age-appropriate in all 11 individuals. PWS children, aged 15-16 years, had postoperative respiratory and infectious complications necessitating hospitalizations of 13-22 days (versus 5.1 ± 1.2 days in non-PWS). Weight loss and comorbidity improvement lasted approximately 5 years, providing improved quality of life for patient and family. One PWS patient died from complications after reoperation for weight regain after 4 years. One was reoperated after 6 years and the third is considering reoperation 14 years after primary DS.

CONCLUSION

The beneficial effects of DS in adolescents exceed the risks, even in the presence of PWS.

Childhood obesity

PURPOSE OF REVIEW

As childhood obesity is associated with premature death in adults, a research is critical. This review focuses on the recent proceedings concerning genesis, prevention, and treatment.

RECENT FINDINGS

Identifying genetic variants in well phenotyped small cohorts of extremely obese children (e.g., the search for copy number variants in obesity-associated large chromosomal deletions) confirmed afterwards in large population-based studies is a new promising genetic approach to understand the disposition to obesity. A further important finding is that obesity of mothers predisposes their offsprings to obesity by epigenetic, prenatal effects. Therefore, prevention programs targeting parents even before pregnancy should be developed. Prevention programs in kindergarten and schools without involving the parents failed to fight against the obesity epidemic. A new promising prevention approach is to change the environment (e.g., ban on sugar drinks in schools). Therapy of choice in already obese children is lifestyle intervention. Again, including their parents is crucial for success. However, this kind of intervention is only suitable for families motivated to change their lifestyle habits. Especially in extremely obese adolescents, additional therapeutic approaches such as drugs and bariatric surgery have to be considered.

SUMMARY

Even if of knowledge of childhood obesity improves every year, many questions concerning prevention and treatment remain still open. Future longitudinal research has to focus on which children will benefit from which kind of intervention to develop specific therapies.

Obesity in pregnancy: implications for the mother and lifelong health of the child. A consensus statement

Obesity among pregnant women is becoming one of the most important women's health issues. Obesity is associated with increased risk of almost all pregnancy complications: gestational hypertension, preeclampsia, gestational diabetes mellitus, delivery of large-for-GA infants, and higher incidence of congenital defects all occur more frequently than in women with a normal BMI. Evidence shows that a child of an obese mother may suffer from exposure to a suboptimal in utero environment and that early life adversities may extend into adulthood. In September 2009, ILSI Europe convened a workshop with multidisciplinary expertise to review practices and science base of health and nutrition of obese pregnant women, with focus on the long-term health of the child. The consensus viewpoint of the workshop identified gaps and gave recommendations for future research on gestational weight gain, gestational diabetes, and research methodologies. The evidence available on short- and long-term health impact for mother and child currently favors actions directed at controlling prepregnancy weight and preventing obesity in women of reproductive ages. More randomized controlled trials are needed to evaluate the effects of nutritional and behavioral interventions in pregnancy outcomes. Moreover, suggestions that maternal obesity may transfer obesity risk to child through non-Mendelian (e.g. epigenetic) mechanisms require more long-term investigation.

Panel report: best practices for the surgical treatment of obesity

BACKGROUND

Bariatric surgery is a rapidly growing field. Advances in surgical technologies and techniques have raised concerns about patient safety. Bariatric surgeons and programs are under increased scrutiny from regulatory agencies, insurers, and public health officials to provide high quality and safe care for bariatric patients at all phases of care.

METHODS

During the 2009 annual meeting of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), a panel of experts convened to provide updated information on patient safety and best practices in bariatric surgery. The following article is a summary of this panel presentation.

RESULTS AND CONCLUSIONS

Weight loss surgery is a field that is evolving and adapting to multiple external pressures. Safety concerns along with increasing public scrutiny have led to a systematic approach to defining best practices, creating standards of care, and identifying mechanisms to ensure that patients consistently receive the best and most effective care possible. In many ways, bariatric surgery and multidisciplinary bariatric surgery programs may serve as a model for other programs and surgical specialties in the near future.

Pregnancy after bariatric surgery

The incidence of obesity is increasing rapidly, and it affects a greater proportion of women than men. Unfortunately, obesity has a negative impact on women's reproductive health, including increased adverse perinatal outcomes. Weight loss surgery, also known as bariatric surgery, is performed in many hospitals, and can allow for significant weight loss and improvement in medical comorbidities such as diabetes and hypertension. A woman who becomes pregnant after bariatric surgery usually has an uncomplicated pregnancy but requires special attention to some complications that can occur after these procedures. This article reviews the perinatal outcomes and provides recommendations for care regarding the unique issues that arise during a pregnancy after bariatric surgery.

Maternal obesity and infant outcomes

Obesity (Body mass index (BMI) above 30) is one of the major health issues of the 21st century. Over 1.1 billion of the world's population are now classified as obese. In the UK, women are more likely to be obese than men; over 50% of women of reproductive age are overweight or obese. Maternal obesity and the plethora of associated conditions, have a serious impact on the health and development of their offspring. In this review we describe the direct and indirect impact of maternal obesity on the health of the baby. Maternal obesity affects conception, duration and outcome of pregnancy. Offspring are at increased risk of both immediate and long term implications for health. We also briefly review potential mechanisms drawing on data from human and animal studies, and on the outcomes of clinical interventional studies.

Impact of maternal obesity on offspring obesity and cardiometabolic disease risk

The prevalence of obesity among pregnant women is increasing. In addition to the short-term complications of obesity during pregnancy in both mother and child, it is now recognised that maternal obesity has long-term adverse outcomes for the health of her offspring in later life. Evidence from both animal and human studies indicates that maternal obesity increases the risk for the offspring in developing obesity and altering body composition in child- and adulthood and, additionally, it also has an impact on the offspring's cardiometabolic health with dysregulation of metabolism including glucose/insulin homoeostasis, and development of hypertension and vascular dysfunction. Potential mechanisms include effects on the development and function of adipose tissue, pancreas, muscle, liver, the vasculature and the brain. Further studies are required to elucidate the mechanisms underpinning the programming of disease risk in the offspring as a consequence of maternal obesity. The ultimate aim is to identify potential targets, which may be amenable to prevention or early intervention in order to improve the health of this and future generations.

Neurobiology of food addiction

PURPOSE OF REVIEW

To review recent work on disorders related to food use, including food addiction, and to highlight the similarities and differences between food and drugs of abuse.

RECENT FINDINGS

Recent work on food use disorders has demonstrated that the same neurobiological pathways that are implicated in drug abuse also modulate food consumption, and that the body's regulation of food intake involves a complex set of peripheral and central signaling networks. Moreover, new research indicates that rats can become addicted to certain foods, that men and women may respond differently to external food cues, and that the intrauterine environment may significantly impact a child's subsequent risk of developing obesity, diabetes, and hypercholesterolemia.

SUMMARY

First, work presented in this review strongly supports the notion that food addiction is a real phenomenon. Second, although food and drugs of abuse act on the same central networks, food consumption is also regulated by peripheral signaling systems, which adds to the complexity of understanding how the body regulates eating, and of treating pathological eating habits. Third, neurobiological research reviewed here indicates that traditional pharmacological and behavioral interventions for other substance-use disorders may prove useful in treating obesity.

Maternal overweight programs insulin and adiponectin signaling in the offspring

Gestational exposure to maternal overweight (OW) influences the risk of obesity in adult life. Male offspring from OW dams gain greater body weight and fat mass and develop insulin resistance when fed high-fat diets (45% fat). In this report, we identify molecular targets of maternal OW-induced programming at postnatal d 21 before challenge with the high-fat diet. We conducted global transcriptome profiling, gene/protein expression analyses, and characterization of downstream signaling of insulin and adiponectin pathways in conjunction with endocrine and biochemical characterization. Offspring born to OW dams displayed increased serum insulin, leptin, and resistin levels (P < 0.05) at postnatal d 21 preceding changes in body composition. A lipogenic transcriptome signature in the liver, before development of obesity, was evident in OW-dam offspring. A coordinated locus of 20 sterol regulatory element-binding protein-1-regulated target genes was induced by maternal OW. Increased nuclear levels of sterol regulatory element-binding protein-1 and recruitment to the fatty acid synthase promoter were confirmed via ELISA and chromatin immunoprecipitation analyses, respectively. Higher fatty acid synthase and acetyl coenzyme A carboxylase protein and pAKT (Thr(308)) and phospho-insulin receptor-beta were confirmed via immunoblotting. Maternal OW also attenuated AMP kinase/peroxisome proliferator-activated receptor-alpha signaling in the offspring liver, including transcriptional down-regulation of several peroxisome proliferator-activated receptor-alpha-regulated genes. Hepatic mRNA and circulating fibroblast growth factor-21 levels were significantly lower in OW-dam offspring. Furthermore, serum levels of high-molecular-weight adiponectin (P < 0.05) were decreased in OW-dam offspring. Phosphorylation of hepatic AMP-kinase (Thr(172)) was significantly decreased in OW-dam offspring, along with lower AdipoR1 mRNA. Our results strongly suggest that gestational exposure to maternal obesity programs multiple aspects of energy-balance regulation in the offspring.