Stressful Experiences in Early Life and Subsequent Food Intake

A number of studies have indicated a strong correlation between traumatic events during early life and the development of behavioral abnormalities later in life, including psychoemotional disorders such as anxiety and depression. Patients with eating disorders frequently exhibit symptoms of depression and/or anxiety, as well as reporting experiences of childhood abuse, a type of early-life trauma. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis is implicated in the pathophysiology not only of anxiety and depression, but also of eating disorders. Neonatal maternal separation and isolation rearing in rodents are well-known animal models of stressful experiences in early life. Many studies have demonstrated their impacts both on the activity of the HPA axis and on the development of psychoemotional disorders later in life. This chapter reviews research using animal models of eating disorders associated with stress in early life. Results suggest that neonatal maternal separation leads to the development of binge-related eating disorders when it is challenged with social or metabolic stressors later in life, in which dysfunctions in the HPA axis and the brain monoaminergic systems may play important roles. Also, social isolation in adolescence induces hyperphagia and depression-like behaviors in female rats, but not in males; a tonic increase of plasma corticosterone seems to be implicated in its underlying mechanism.