Relevance of animal models to human eating disorders and obesity

Background and rationale This review addresses the role animal models play in contributing to our knowledge about the eating disorders anorexia nervosa (AN) and bulimia nervosa (BN) and obesity. Objectives Explore the usefulness of animal models in complex biobehavioral familial conditions, such as AN, BN, and obesity, that involve interactions among genetic, physiologic, psychological, and cultural factors. Results and conclusions The most promising animal model to mimic AN is the activity-based anorexia rodent model leading to pathological weight loss. The paradigm incorporates reward elements of the drive for activity in the presence of an appetite and allows the use of genetically modified animals. For BN, the sham-feeding preparation in rodents equipped with a gastric fistula appears to be best suited to reproduce the postprandial emesis and the defects in satiety. Animal models that incorporate genes linked to behavior and mood may clarify biobehavioral processes underlying AN and BN. By contrast, a relative abundance of animal models has contributed to our understanding of human obesity. Both environmental and genetic determinants of obesity have been modeled in rodents. Here, we consider single gene mutant obesity models, along with models of obesigenic environmental conditions. The contributions of animal models to obesity research are illustrated by their utility for identifying genes linked to human obesity, for elucidating the pathways that regulate body weight and for the identification of potential therapeutic targets. The utility of these models may be further improved by exploring the impact of experimental manipulations on the behavioral determinants of energy balance.