Eating disorders: from bench to bedside and back.

The central nervous system and viscera constitute a functional ensemble, the gut-brain axis, that allows bidirectional information flow that contributes to the control of feeding behavior based not only on the homeostatic, but also on the hedonic aspects of food intake. The prevalence of eating disorders, such as anorexia nervosa, binge eating and obesity, poses an enormous clinical burden, and involves an ever-growing percentage of the population worldwide. Clinical and preclinical research is constantly adding new information to the field and orienting further studies with the aim of providing a foundation for developing more specific and effective treatment approaches to pathological conditions. A recent symposium at the XVI Congress of the Societá Italiana di Neuroscienze (SINS, 2015) 'Eating disorders: from bench to bedside and back' brought together basic scientists and clinicians with the objective of presenting novel perspectives in the neurobiology of eating disorders. Clinical studies presented by V. Ricca illustrated some genetic aspects of the psychopathology of anorexia nervosa. Preclinical studies addressed different issues ranging from the description of animal models that mimic human pathologies such as anorexia nervosa, diet-induced obesity, and binge eating disorders (T. Lutz), to novel interactions between peripheral signals and central circuits that govern food intake, mood and stress (A. Romano and G. Provensi). The gut-brain axis has received increasing attention in the recent years as preclinical studies are demonstrating that the brain and visceral organs such as the liver and guts, but also the microbiota are constantly engaged in processes of reciprocal communication, with unexpected physiological and pathological implications. Eating is controlled by a plethora of factors; genetic predisposition, early life adverse conditions, peripheral gastrointestinal hormones that act directly or indirectly on the central nervous system, all are receiving attention as they presumably contribute to the development of eating disorders.