Higher body mass index is linked to altered hypothalamic microstructure.

Animal studies suggest that obesity-related diets induce structural changes in the hypothalamus, a key brain area involved in energy homeostasis. Whether this translates to humans is however largely unknown. Using a novel multimodal approach with manual segmentation, we here show that a higher body mass index (BMI) selectively predicted higher proton diffusivity within the hypothalamus, indicative of compromised microstructure in the underlying tissue, in a well-characterized population-based cohort (n1 = 338, 48% females, age 21-78 years, BMI 18-43 kg/m²). Results were independent from confounders and confirmed in another independent sample (n2 = 236). In addition, while hypothalamic volume was not associated with obesity, we identified a sexual dimorphism and larger hypothalamic volumes in the left compared to the right hemisphere. Using two large samples of the general population, we showed that a higher BMI specifically relates to altered microstructure in the hypothalamus, independent from confounders such as age, sex and obesity-associated co-morbidities. This points to persisting microstructural changes in a key regulatory area of energy homeostasis occurring with excessive weight. Our findings may help to better understand the pathomechanisms of obesity and other eating-related disorders.

Eat your troubles away: electrocortical and experiential correlates of food image processing are related to emotional eating style and emotional state.

Emotional eating, a trait-like style of food intake in response to negative emotion states, represents an important aspect of overeating and eating related psychopathology. The mechanisms of emotional eating both on experiential and neuronal levels are not well delineated. We recorded event related potentials (ERPs) while individuals with high or low emotional eating style (HEE, n=25; LEE, n=20) viewed and rated pictures of high-caloric food during neutral state vs. negative idiosyncratic emotion induction. Craving ratings increased in HEE and decreased in LEE during negative relative to neutral states. ERPs to food pictures showed an enhanced late positive potential (LPP) over parieto-occipital regions for HEE compared to LEE. Emotional state modulated food picture evoked ERPs over right frontal regions in HEE only. This suggests that appetitive food processing is susceptible to both concurrent emotion and habitual eating style which is of relevance for overeating in healthy and abnormal eating.

Eating disorders and headache: coincidence or consequence?

The eating disorders (ED) anorexia nervosa (AN) and bulimia nervosa (BN) are important psychiatric and somatic conditions occurring mainly in young women. The aetiology is unknown, but there are social, biological and psychological factors that play a relevant role in the pathogenesis, along with multiple endocrine abnormalities. Hypothalamic monoamines (especially serotonin), neuropeptides (especially neuropeptide Y and cholecystokinin) and leptin are involved in the regulation of the human appetite. ED share with migraine the same metabolic profile and aspect of psychiatric and psychological conditions. In support of this hypothesis in one study, it has been shown that the incidence of migraine is high in these patients; and it has been shown that the incidence in a female group that suffers from migraine was greater than in the normal population. In order to understand the possible relationship between migraine and ED, we have investigated the incidence of primary headache in a group of AN and BN patients. The result of this study shows that the prevalence of migraine in women affected by AN and BN is very high (75%) in comparison to the general population (12.5% headache incidence in normal population). In most patients the onset of migraine attacks began before or at the same time as the symptoms of AN and BN. We suggest that migraine is a predisposing condition for the occurence of AD in young women.

Disseminated pilocytic astrocytoma involving brain stem and diencephalon: a history of atypical eating disorder and diagnostic delay.

The association of weight loss and pediatric brain tumors that affect the diencephalon or brain stem with weight loss is a recognized, but not fully understood phenomenon. Tumors located in the hypothalamic region may induce the diencephalic syndrome (DS), which is characterized by profound emaciation with almost complete loss of subcutaneous fatty tissue. Tumors that compress or infiltrate the brain stem rarely cause both psychological disturbance and emaciation. The clinical presentation may be different, depending on the location of the lesion and age of the patient. In this report we present an unusual case of severe emaciation in a 4(9)/(12)-year-old girl with a juvenile pilocytic astrocytoma of the hypothalamic region and brain stem with neuroaxis dissemination. This case illustrates the importance of considering intracranial mass-lesions in the differential diagnosis of weight loss, psychological disturbance and atypical eating disorder. We discuss the importance of tumor multifocality and the role of patient age in the clinical presentation with reference to the literature.

Tratamento nutricional dos transtornos alimentares / Nutritional treatment of eating disorders

Pacientes com transtornos alimentares possuem inadequaçäes profundas no consumo, padrão e comportamento alimentar, além de diversas crenças equivocadas sobre alimentação, o que geralmente acarreta piora do estado nutricional. O tratamento nutricional visa a reverter tais alteraçäes e promover hábitos alimentares saudáveis e melhor relação para com o alimento. Os objetivos e características do tratamento diferem para a anorexia nervosa e a bulimia nervosa, contudo, usualmente, a abordagem é dividida em duas fases: a educacional, cujas principais metas são a regularização do hábito alimentar e o aumento do conhecimento nutricional, e a experimental, que visa a propiciar maior reabilitação nutricional e mudanças mais profundas no comportamento alimentar. As evidências existentes sugerem que o tratamento nutricional promove a melhora de tais parâmetros, porém, alguns comportamentos alimentares, como a sensação de incompetência ao lidar com os alimentos, permanecem. Desta forma, mais estudos são necessários para que se possa de fato avaliar a eficácia da abordagem nutricional.

A pathologic basis for Kleine-Levin syndrome.

A patient with Kleine-Levin syndrome, typical except that onset was at 39 years of age, died during a symptomatic period. Autopsy disclosed recent and old lesions in the medial thalamus involving intralaminar, medial, and some dorsal nuclei as well as the pulvinar. Despite massive microglial infiltration, there was minimal neuronal loss. The hypothalamus was not involved. The findings suggest a viral cause for Kleine-Levin syndrome.

Effect of induced hypothalamic hyperphagia and forced-feeding on organ weight and tissular development in Landes geese.

The effects of induced hypothalamic hyperphagia and forced-feeding were studied in 30 geese of the Landes breed. They were housed in individual cages under a dark-light cycle of 12 hrs light-12 hrs darkness. Eleven geese with ventromedian hypothalamic (VMH) lesions and 8 controls were fed ad libitum. A third lot of 11 force-fed animals was pair-fed with the operated geese. The study lasted 4 weeks after an adaptation period to the new environmental conditions. The daily food intake of the geese and their weekly liveweight gain were monitored. After VMH lesions, the mean food intake of the geese increased by 169 p. 100 so that after each treatment their liveweight increased and they became obese (P less than 0.001). The tissue distribution of the group with lesions showed a higher amount of subcutaneous fat (P less than 0.05), while the mesenteric fat (P less than 0.05) was more abundant after forced-feeding. The liver weight was much higher in all cases; its increment reached 311 p. 100 in geese with VMH lesions and 193 p. 100 in the force-fed. However, those values were too low when compared to the means obtained by traditional forced-feeding. Hyperphagia in the geese was very marked as compared to that in rats, but it was insufficient to produce a considerable hepatic steatosis.