leptin and Psychomotor-Agitation

Anorexia nervosa (AN) belongs to a group of eating disorders and is characterized by extreme body weight loss. AN patients show combination of physical, psychological and behavioral disturbances. Neuropeptides partly control energy homeostasis and modulate hormone release. Leptin, a peptide secreted by adipocytes, may influence the interactions between central and peripheral signals. Hypoleptinaemia found in AN is connected with disturbed control of appetite and hormonal dysfunction as well as has implications for the hypothalamo-pituitary-gonadal axis, bone mineral density and physical hyperactivity. Low leptin levels are increased with refeeding. However, the prolonged hypoleptinaemia in weight recovered AN patients may result in persistent hypothalamic amenorrhoea. The hyperactivity has been observed in 31-80 % of AN cases. The mechanisms underlying the hyperactivity found in patients with anorexia nervosa seem to be more complicated as many factors including neuropeptides may be involved. Orexins may affect not only appetite but also behavior and psychophysical activity as they may regulate reproductive and stress hormone secretion, stimulate a variety of stereotypic behaviors including eating and stress reaction, and affect the hypothalamo-pituitary-adrenal (HPA) axis, alter glucocorticoid and catecholamine secretion and activate the sympathetic nervous system. Orexins influence the mechanism regulating arousal and sleep, cardiovascular function, temperature, metabolic rate and locomotive activity. It is worth considering how abnormal activity of hypothalamic neuropeptides or their receptors may play a role in the mechanisms of hyperactivity, disturbed control of appetite and hormonal dysfunction in patients with anorexia nervosa.

Topics: Anorexia Nervosa; Humans; Hypothalamo-Hypophyseal System; Intracellular Signaling Peptides and Proteins; Leptin; Neuropeptides; Orexins; Pituitary-Adrenal System; Psychomotor Agitation

This paper discusses the hypothesis that a 'drive for activity" in the presence of physiological and endocrine changes consistent with starvation is a characteristic symptom of acute anorexia nervosa (AN). This 'drive for movement', along with alertness and lack of fatigue, so unlike the motor slowing and loss of energy observed in simple starvation has been recognized in AN throughout history, but has received little attention in the past fifty years. Clinical reports and experimental evidence suggest that 'restlessness' and a 'drive for activity' vary in intensity, they appears to be starvation-dependent and to wane with food intake. Central nervous system (CNS) systems known to be involved in mediating activity and arousal levels that are altered by the negative energy expenditure in AN are reviewed. Among these, the corticotropin-releasing hormone (CRH) system, the melanocyte stimulating hormone/agouti-related protein (MSH/AGRP) system and the norepinephrine/epinephrine (NE/EPI) and dopamine (DA) system may contribute to the 'drive for activity' and alertness in AN. AN appears to represent a disorder of gene/environment interaction. Future research will reveal whether in individuals predisposed to AN, the 'drive for activity' reflects the reactivation of mechanisms important in food scarcity, controlled by one or more evolutionary conserved genes including those regulating foraging behavior. Recognition of the 'drive for activity' as a diagnostic symptom of AN and its assessment prior to re-nutrition would permit clarification of its role in the etiology of AN.

Topics: Anorexia Nervosa; Corticotropin-Releasing Hormone; Dopamine; Humans; Hypothalamo-Hypophyseal System; Leptin; Melanocyte-Stimulating Hormones; Norepinephrine; Pituitary-Adrenal System; Psychomotor Agitation; Serotonin; Thyrotropin

Migratory flights by birds are among the most energetically demanding forms of animal movement, and are primarily fueled by fat as an energy source. Leptin is a critical fat-regulation hormone associated with energy balance in non-avian species but its function in birds is highly controversial. Prior research indicated the effects of leptin differed between birds in migratory condition or not, but no research has assessed the effect of leptin on migratory behaviour itself. In this study, our objective was to determine if leptin affects migratory restlessness and fat deposition in migratory songbirds. We used photoperiod manipulation to induce spring migratory condition, and measured migratory restlessness in leptin-injected and saline-injected white-throated sparrows (

Topics: Animal Migration; Animals; Leptin; Photoperiod; Psychomotor Agitation; Sparrows

The hypothesis linking hyperactivity with weight loss associated hypoleptinemia in anorexia nervosa gained momentum after a study showing that leptin suppressed semi-starvation induced hyperactivity in rats. Alternatively, ambient temperature is a key modulating factor of activity in semi-starved rats. The aim of the study is to compare the efficacy of leptin with increased ambient temperature in the prevention of hyperactivity in semi-starved rats. 74 Sprague-Dawley male rats were employed in two experiments with the difference residing in the length of baseline. After an extended (28 days), or shorter (14 days) baseline with free access to food and the running wheel, housed at 21 °C, animals were either ad-lib feed or food restricted (60% of food ingested during previous week) and infused with same amount of leptin at 21 °C, 25 °C, or vehicle at 21 °C, 25 °C and 32 °C for a week. Animals housed at 32 °C significantly reduced wheel running and weight loss during food restriction while animals given leptin did not yield no differences in activity or weight loss. Moreover, unlike animals housed at 32 °C, body temperature of leptin infused animals housed at 21 °C was significantly reduced during food restriction. Furthermore, leptin treated rats without a preceding stable pattern of activity displayed a severe dysregulation of circadian rhythm in activity and a collapse of body temperature. Housing temperature plays a more critical role than leptin in the regulation of semi-starvation induced hyperactivity in rats, which may be of relevance for the management of hyperactivity in anorexia nervosa.

Topics: Animals; Anorexia Nervosa; Hyperkinesis; Leptin; Male; Motor Activity; Physical Conditioning, Animal; Psychomotor Agitation; Rats; Rats, Sprague-Dawley; Starvation; Temperature

The aim of the present study was to verify the influence of hyperactivity on internistic and psychiatric parameters in early onset anorexia nervosa restricting type (ANR).. Seventy-three adolescent females (mean age 13.5 years, SD: 2.27) with a diagnosis of ANR (DSM-IV-TR) were consecutively enrolled in the Child and Adolescent Eating Disorders Unit of the IRCCS-Stella Maris and assessed by an extensive clinical protocol. All patients completed: psychiatric evaluation for description of the DCA and comorbidities; pediatric assessment including complete auxological data, blood pressure, heart rate and other electro/echo cardiographic and biohumoral parameters. The hyperactivity was estimated by the application of the "Structured Interview for Anorexic and Bulimic Disorder-Expert Form" (Item 40) in the context of clinical observation. Subjects were identified according to their level of hyperactive (ANR+H) and non-hyperactive (ANR-H) activity.. In the ANR+H group heart rate, leptin, sodium, potassium and gamma plasma proteins significantly differ compared to the group ANR-H. Patients with hyperactivity also have a complete form of ANR in 94% of cases compared with 66.7% of non-hyperactive; significant differences were found also in thought and attention CBCL and YSR subscales, combined with major internalizing problems.. This study provides preliminary data which can orient research towards the development of specific treatments for the hyperactivity, in order to improve the prognosis and thus avoid the chronicity of the disorder and the development of complications in adult life.

Topics: Adolescent; Adolescent Behavior; Anorexia Nervosa; Biomarkers; Body Mass Index; Comorbidity; Female; Heart Rate; Humans; Italy; Leptin; Potassium; Prognosis; Psychomotor Agitation; Serum Albumin; Sodium; Surveys and Questionnaires

In food-restricted rats, leptin suppresses semistarvation-induced hyperactivity (SIH) and decreases exploratory behavior. Leptin ameliorates anxiety-related movement in ob/ob mice. In this study, we assessed the relationship between leptin and qualities of physical activity and restlessness in acute anorexia nervosa (AN).. Serum leptin, body mass index (BMI), % body fat, and self- and expert-ratings of qualities of physical activity and restlessness were assessed in 26 inpatients with acute AN. Accelerometry was also performed. Regression analyses were used to predict activity and restlessness using BMI, % body fat, and leptin levels as predictor variables.. Leptin levels significantly contributed to the prediction of all measures of activity and restlessness.. This is the first study linking hypoleptinemia in AN patients to subjective and objective measures of higher physical activity and motor and inner restlessness. Leptin may directly or indirectly (or both) influence behaviors and cognitions contributing to hyperactivity and motor restlessness.

Topics: Adolescent; Adolescent Behavior; Anorexia Nervosa; Body Composition; Body Mass Index; Female; Humans; Kinetocardiography; Leptin; Motor Activity; Predictive Value of Tests; Psychomotor Agitation; Self Disclosure; Surveys and Questionnaires

Low leptin levels are an endocrinological hallmark of acute anorexia nervosa (AN); a subthreshold leptin secretion in adipocytes as a consequence of a reduced energy intake is presumed to be the major trigger of the adaptation of an organism to semistarvation. The aim of the current study is to define symptoms of AN that are potentially linked to low leptin levels. For this purpose, quantitative somatic and psychopathological variables were obtained in 61 inpatients with acute AN (study group 1) upon referral for inpatient treatment, and they were concomitantly blood sampled to allow determination of serum leptin levels. Correlations between these variables and logarithmic transformed (lg10) leptin levels were descriptively assessed. Apart from the well-known correlations between leptin levels and anthropometric measurements, the strongest correlation was observed between lg10 serum leptin levels and expert ratings of motor restlessness (r = -0.476; nominal P = 0.003) upon use of visual analog scales. We thus generated the hypothesis that physical activity levels in AN patients are related to serum leptin levels. This hypothesis was tested in an independent study group of 27 adolescent inpatients (study group 2) who were also assessed upon referral. Physical activity levels, which, in this study group, were assessed with the activity module of the expert rating form of the Structured Inventory for Anorexic and Bulimic Syndromes, were significantly correlated with lg10 leptin levels (r = -0.51; one-sided P = 0.006). A regression model based on the independent variables body mass index and lg10 leptin levels explained 37% of the variance of physical activity (R(2) = 0.37; P = 0.003); only the lg10 leptin levels contributed significantly to the variance (P = 0.003). Our results suggest that, similar to semistarvation-induced hyperactivity in rats, hypoleptinemia in patients with AN may be one important factor underlying the excessive physical activity.

Topics: Acute Disease; Adaptation, Physiological; Adolescent; Adult; Anorexia Nervosa; Child; Female; Humans; Leptin; Motor Activity; Psychomotor Agitation