The role of orexigenic and anorexigenic factors in an interdisciplinary weight loss therapy for obese adolescents with symptoms of eating disorders

Crosstalk between Melanin Concentrating Hormone and Endocrine Factors: Implications for Obesity

Melanin-concentrating hormone (MCH) is a 19aa cyclic peptide exclusively expressed in the lateral hypothalamic area, which is an area of the brain involved in a large number of physiological functions and vital processes such as nutrient sensing, food intake, sleep-wake arousal, memory formation, and reproduction. However, the role of the lateral hypothalamic area in metabolic regulation stands out as the most relevant function. MCH regulates energy balance and glucose homeostasis by controlling food intake and peripheral lipid metabolism, energy expenditure, locomotor activity and brown adipose tissue thermogenesis. However, the MCH control of energy balance is a complex mechanism that involves the interaction of several neuroendocrine systems. The aim of the present work is to describe the current knowledge of the crosstalk of MCH with different endocrine factors. We also provide our view about the possible use of melanin-concentrating hormone receptor antagonists for the treatment of metabolic complications. In light of the data provided here and based on its actions and function, we believe that the MCH system emerges as an important target for the treatment of obesity and its comorbidities.

Semi-intensive and Intensive Interdisciplinary Treatments Have Similar Effects on Metabolic Syndrome and Selected Inflammatory Markers in Adolescents with Obesity

Background

The purpose of the present study was to compare the impact of semi-intensive and intensive interdisciplinary weight-loss therapies on the treatment of metabolic syndrome (MS) and selected inflammatory markers in adolescents with obesity.

Methods

The study included 166 adolescents enrolled in two groups for 22 weeks: the intensive group (in-person aerobic and resistance exercise three times a week, and psychological and nutritional counselling once a week), or the semi-intensive group (six in-person exercise orientation meetings and six in-person psychological support sessions with an online nutritional and exercise program). Anthropometric parameters, blood pressure, fasting glucose, insulin, lipid profile, triglycerides (TG), leptin and adiponectin were assessed before and after the interventions.

Results

Body weight and waist circumference decreased in both groups (P<0.001) and large effect sizes (η²= 0.586 and η²=0.465, respectively) were noted. Significant time and group interactions were found (P=0.001) with medium effect sizes (η²=0.095 and η²=0.105, respectively). The prevalence of MS decreased from 27.9% to 13.1% (P=0.012) and 29.4% to 5.9% (P=0.004) in the semi-intensive and intensive groups, respectively. All MS risk factors decreased significantly over time (P<0.001) and a significant time*group interaction was observed (P<0.05), except for fasting TG (P=0.832) and glucose (P=0.128, η²=0.021).

Conclusion

The results suggested that both approaches promoted significant clinical improvement in the condition of adolescents with MS and reduced associated risk factors. Studies that consider the cost effectiveness of both treatments are still needed to determine whether semi-intensive care, with its lower financial costs, may be a suitable option to treat obesity and MS in adolescents with obesity.

A systematic review of binge eating, loss of control eating, and weight loss in children and adolescents

OBJECTIVE

This review synthesizes literature on changes in binge eating (BE) and loss of control eating (LOC) following weight loss and the association between BE/LOC and weight loss in children and adolescents.

METHODS

A systematic literature search was conducted in PubMed, Scopus, and PsycInfo. Eligible studies included all peer-reviewed journal articles of primary research that assessed BE/LOC and weight change following a weight-loss intervention in individuals under 18 years of age.

RESULTS

The 29 articles included studies on behavioral therapy, pharmacotherapy, and surgical interventions. Of the 14 studies that assessed the relationship between weight loss and BE/LOC at baseline, 4 showed that higher baseline BE/LOC was associated with less weight loss, whereas 10 showed no significant association. BE/LOC behaviors significantly decreased following weight-loss interventions in 20 of 21 studies. A greater decrease in BE/LOC was associated with improved weight loss in 4 of 9 studies that assessed this change.

CONCLUSIONS

Weight-loss interventions are associated with improved BE/LOC in youth with obesity. The persistence of BE/LOC symptoms may be associated with less weight loss. These results can aid in guiding future treatment for youth with BE/LOC seeking weight-loss treatment.

The Rat Mammary Gland as a Novel Site of Expression of Melanin-Concentrating Hormone Receptor 1 mRNA and Its Protein Immunoreactivity

Lactation is a complex physiological process, depending on orchestrated central and peripheral events, including substantial brain plasticity. Among these events is a novel expression of pro-melanin-concentrating hormone (Pmch) mRNA in the rodent hypothalamus, such as the ventral part of the medial preoptic area (vmMPOA). This expression reaches its highest levels around postpartum day 19 (PPD19), when dams transition from lactation to the weaning period. The appearance of this lactation-related Pmch expression occurs simultaneously with the presence of one of the Pmch products, melanin-concentrating hormone (MCH), in the serum. Given the relevance of the MPOA to maternal physiology and the contemporaneity between Pmch expression in this structure and the weaning period, we hypothesized that MCH has a role in the termination of lactation, acting as a mediator between central and peripheral changes. To test this, we investigated the presence of the MCH receptor 1 (MCHR1) and its gene expression in the mammary gland of female rats in different stages of the reproductive cycle. To that end, in situ hybridization, RT-PCR, RT-qPCR, nucleotide sequencing, immunohistochemistry, and Western blotting were employed. Although Mchr1 expression was detected in the epidermis and dermis of both diestrus and lactating rats, parenchymal expression was exclusively found in the functional mammary gland of lactating rats. The expression of Mchr1 mRNA oscillated through the lactation period and reached its maximum in PPD19 dams. Presence of MCHR1 was confirmed with immunohistochemistry with preferential location of MCHR1 immunoreactive cells in the alveolar secretory cells. As was the case for gene expression, the MCHR1 protein levels were significantly higher in PPD19 than in other groups. Our data demonstrate the presence of an anatomical basis for the participation of MCH peptidergic system on the control of lactation through the mammary gland, suggesting that MCH could modulate a prolactation action in early postpartum days and the opposite role at the end of the lactation.

Treatment of obesity, with a dietary component, and eating disorder risk in children and adolescents: A systematic review with meta-analysis

This review aimed to investigate the impact of obesity treatment, with a dietary component, on eating disorder (ED) prevalence, ED risk, and related symptoms in children and adolescents with overweight or obesity. Four databases were searched to identify pediatric obesity treatment interventions, with a dietary component, and validated pre-post intervention assessment of related outcomes. Of 3078 articles screened, 36 met inclusion criteria, with a combined sample of 2589 participants aged 7.8 to 16.9 years. Intervention duration ranged from 1 week to 13 months, with follow-up of 6 months to 6 years from baseline. Prevalence of ED was reported in five studies and was reduced post-intervention. Meta-analyses showed a reduction in bulimic symptoms (eight studies, standardized mean difference [SE], -0.326 [0.09], P < 0.001), emotional eating (six studies, -0.149 [0.06], P = 0.008), binge eating (three studies, -0.588 [0.10], P < 0.001), and drive for thinness (three studies, -0.167 [0.06], P = 0.005) post-intervention. At follow-up, a reduction in ED risk (six studies, -0.313 [0.13], P = 0.012), emotional eating (five studies, -0.259 [0.05], P < 0.001), eating concern (three studies, -0.501 [0.06], P < 0.001), and drive for thinness (two studies, -0.375 [0.07], P < 0.001) was found. Structured and professionally run obesity treatment was associated with reduced ED prevalence, ED risk, and symptoms.

The Melanin-Concentrating Hormone as an Integrative Peptide Driving Motivated Behaviors

The melanin-concentrating hormone (MCH) is an important peptide implicated in the control of motivated behaviors. History, however, made this peptide first known for its participation in the control of skin pigmentation, from which its name derives. In addition to this peripheral role, MCH is strongly implicated in motivated behaviors, such as feeding, drinking, mating and, more recently, maternal behavior. It is suggested that MCH acts as an integrative peptide, converging sensory information and contributing to a general arousal of the organism. In this review, we will discuss the various aspects of energy homeostasis to which MCH has been associated to, focusing on the different inputs that feed the MCH peptidergic system with information regarding the homeostatic status of the organism and the exogenous sensory information that drives this system, as well as the outputs that allow MCH to act over a wide range of homeostatic and behavioral controls, highlighting the available morphological and hodological aspects that underlie these integrative actions. Besides the well-described role of MCH in feeding behavior, a prime example of hypothalamic-mediated integration, we will also examine those functions in which the participation of MCH has not yet been extensively characterized, including sexual, maternal, and defensive behaviors. We also evaluated the available data on the distribution of MCH and its function in the context of animals in their natural environment. Finally, we briefly comment on the evidence for MCH acting as a coordinator between different modalities of motivated behaviors, highlighting the most pressing open questions that are open for investigations and that could provide us with important insights about hypothalamic-dependent homeostatic integration.

Bariatric endocrinology: principles of medical practice

Obesity, is a chronic, biological, preventable, and treatable disease. The accumulation of fat mass causes physical changes (adiposity), metabolic and hormonal changes due to adipose tissue dysfunction (adiposopathy), and psychological changes. Bariatric endocrinology was conceived from the need to address the neuro-endocrinological derangements that are associated with adiposopathy, and from the need to broaden the scope of the management of its complications. In addition to the well-established metabolic complications of overweight and obesity, adiposopathy leads to hyperinsulinemia, hyperleptinemia, hypoadiponectinemia, dysregulation of gut peptides including GLP-1 and ghrelin, the development of an inflammatory milieu, and the strong risk of vascular disease. Therapy for adiposopathy hinges on effectively lowering the ratio of orexigenic to anorexigenic signals reaching the the hypothalamus and other relevant brain regions, favoring a lower caloric intake. Adiposopathy, overweight and obesity should be treated indefinitely with the specific aims to reduce fat mass for the adiposity complications, and to normalize adipose tissue function for the adiposopathic complications. This paper defines the principles of medical practice in bariatric endocrinology-the treatment of overweight and obesity as means to treat adiposopathy and its accompanying metabolic and hormonal derangements.

Binge eating in obese adolescents: an evolutionary concept analysis

PURPOSE

The purpose of this paper is to provide an analysis of the concept of binge eating in obese adolescents.

METHODS

Rodgers' evolutionary approach was used to frame this analysis. A search was conducted within the Cumulative Index to Nursing and Allied Health Literature, Medline, and PsycINFO for publications between 1980 and 2011.

FINDINGS

Conceptual shifts in the meaning of binge eating have occurred over the past 30 years, yet the two enduring attributes are consumption of a large amount of food and a loss of control over eating.

CONCLUSION

Though this analysis demonstrates a consensus concerning the core attributes of binge eating, further refinement of the nuances, subtleties, and use of the concept in relation to adolescents is needed.

Aerobic training (AT) is more effective than aerobic plus resistance training (AT+RT) to improve anorexigenic/orexigenic factors in obese adolescents

BACKGROUND

The regulation of energy balance is influenced by physical exercise. Although some studies show a stimulation of hormones related to food intake, others show that exercise provides satiety.

AIM

The aim of this study was to compare the effects of aerobic training (AT) and aerobic plus resistance training (AT+RT) on anorexigenic and orexigenic factors in obese adolescents undergoing interdisciplinary weight loss therapy.

METHODS

A total of 26 obese adolescents, aged 15-19 years with BMI≥P95 were submitted to 12 months of interdisciplinary intervention (clinical support, nutrition, psychology and physical exercise) and divided into two groups, aerobic training (AT) (n=13) or aerobic plus resistance training (AT+RT) (n=13), which were matched according to gender and body mass. Blood samples were collected to analyze orexigenic factors (AgRP, NPY, MCH) and the anorexigenic factor alpha-MSH.

RESULTS

The AT and AT+RT groups significantly reduced body mass, body mass index and body fat mass (kg) during the therapy. The AT group showed no significant changes in body lean mass (kg), whereas the AT+RT group showed an increase in body lean mass (kg) during the interdisciplinary intervention. There was an increase in AgRP levels (ng/ml) only in the AT+RT group after 6 months of interdisciplinary intervention compared with baseline condition. Conversely, α-MSH levels (ng/ml) increased only in the AT group after 12 months of interdisciplinary intervention compared with baseline condition.

CONCLUSION

Aerobic training (AT) as part of an interdisciplinary therapy is more effective than aerobic plus resistance training (AT+RT) to improve secretion of anorexigenic/orexigenic factors in obese adolescents.

Long-term interdisciplinary therapy reduces endotoxin level and insulin resistance in obese adolescents

AIM

The purpose of the present study was to assess the dietary fat intake, glucose, insulin, Homeostasis model assessment for insulin resistance HOMA-IR, and endotoxin levels and correlate them with adipokine serum concentrations in obese adolescents who had been admitted to long-term interdisciplinary weight-loss therapy.

DESIGN

The present study was a longitudinal clinical intervention of interdisciplinary therapy. Adolescents (n = 18, aged 15-19 y) with a body mass index > 95th percentile were admitted and evaluated at baseline and again after 1 year of interdisciplinary therapy. We collected blood samples, and IL-6, adiponectin, and endotoxin concentrations were measured by ELISA. Food intake was measured using 3-day diet records. In addition, we assessed glucose and insulin levels as well as the homeostasis model assessment for insulin resistance (HOMA-IR).

RESULTS

The most important finding from the present investigation was that the long-term interdisciplinary lifestyle therapy decreased dietary fat intake and endotoxin levels and improved HOMA-IR. We observed positive correlations between dietary fat intake and endotoxin levels, insulin levels, and the HOMA-IR. In addition, endotoxin levels showed positive correlations with IL-6 levels, insulin levels and the HOMA-IR. Interestingly, we observed a negative correlation between serum adiponectin and both dietary fat intake and endotoxin levels.

CONCLUSIONS

The present results indicate an association between dietary fat intake and endotoxin level, which was highly correlated with a decreased pro-inflammatory state and an improvement in HOMA-IR. In addition, this benefits effect may be associated with an increased adiponectin level, which suggests that the interdisciplinary therapy was effective in improving inflammatory pathways.

Food restriction and refeeding induces changes in lipid pathways and fat deposition in the adipose and hepatic tissues in rats with diet-induced obesity

The aim of this study was to determine the effects of successive cycles of a moderately restrictive diet and refeeding with a high-fat diet on the metabolism of the adipose and hepatic tissues of obese rats. Rats were assigned to the following groups: a chow diet; a high-fat diet; a moderate caloric restriction; or a moderate caloric restriction plus refeeding. Some animals in each group were given [1-(14)C]triolein intragastrically, while others received an intraperitoneal injection of 3 mCi (3)H(2)O. All animals were killed by decapitation. The retroperitoneal, visceral epididymal and omental white adipose tissues, brown adipose tissue, liver and blood were immediately removed. The lipid uptake from the diet, in vivo rate of lipogenesis, percentage of fat, lipid profile and leptin concentration were analysed. The high-fat diet promoted an increase in fatty liver (P ≤ 0.05), adiposity mass (P ≤ 0.05) and the plasma concentration of leptin (P ≤ 0.05) and a decreased lipid uptake in white adipose tissue depots (P ≤ 0.05) in relation to the chow diet. The moderate caloric restriction did not reverse the changes promoted by the high-fat diet but induced a small decrease in adiposity, which was reversed after refeeding, and the animals maintained a dyslipidaemic profile and high fat deposition in the liver. We can conclude that the high-fat diet and subsequent moderate caloric restriction plus refeeding increased the risks of developing visceral obesity, dyslipidaemia and non-alcoholic fatty liver disease, which suggests that this type of experimental protocol can be used to study mechanisms related to the metabolic syndrome.

Interdisciplinary lifestyle therapy improves binge eating symptoms and body image dissatisfaction in Brazilian obese adults

INTRODUCTION: Obesity is related to numerous negative consequences for physical and mental health. It is often associated with the presence of binge eating disorder, body image dissatisfaction, and general psychopathology. OBJECTIVE: To assess the effects of an interdisciplinary lifestyle therapy on binge eating symptoms, depression, anxiety, body dissatisfaction, and quality of life in obese adults. METHODS: A total of 49 obese adults (body mass index = 37.35±5.82 kg/m²; age = 44.14±10.00 years) participated in a weight-loss program for 6 months. Symptoms suggestive of binge eating, body dissatisfaction, depression, anxiety, and quality of life were measured using self-reported questionnaires. Food intake was assessed using a 3-day dietary record. Data were analyzed using analysis of variance (ANOVA). RESULTS: ANOVA results showed a reduction in binge eating symptoms and in body dissatisfaction results. Depression and anxiety symptoms also decreased, and an increase was observed in quality of life scores. After therapy, a significant improvement was observed in dietary patterns, as well as significant weight loss. A positive correlation was found between variation of anxiety symptoms and lipid intake. Binge eating symptoms were associated with anxiety symptoms and body image dissatisfaction, and body image dissatisfaction correlated positively with anxiety symptoms in males only. In females, a positive correlation was observed between depression and binge eating symptoms. CONCLUSION: The interdisciplinary therapy was effective in promoting positive physical and psychological changes and in improving the quality of life of obese adults.