title: Ghrelin's Role in the Hypothalamic-Pituitary-Adrenal Axis Stress Response: Implications for Mood Disorders.
abstract: Ghrelin is a stomach hormone normally associated with feeding behavior and energy homeostasis. Recent studies highlight that ghrelin targets the brain to regulate a diverse number of functions, including learning, memory, motivation, stress responses, anxiety, and mood. In this review, we discuss recent animal and human studies showing that ghrelin regulates the hypothalamic-pituitary-adrenal axis and affects anxiety and mood disorders, such as depression and fear. We address the neural sites of action through which ghrelin regulates the hypothalamic-pituitary-adrenal axis and associated stress-induced behaviors, including the centrally projecting Edinger-Westphal nucleus, the hippocampus, amygdala, locus coeruleus, and the ventral tegmental area. Stressors modulate many behaviors associated with motivation, fear, anxiety, depression, and appetite; therefore, we assess the potential role for ghrelin as a stress feedback signal that regulates these associated behaviors. Finally, we briefly discuss important areas for future research that will help us move closer to potential ghrelin-based therapies to treat stress responses and related disorders.
authors.affiliation: School of Health Sciences and Health Innovations Research Institute, RMIT University, Bundoora, Melbourne, Victoria, Australia.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Spencer
authors.affiliation: Department of Anatomy, Radboud University Medical Centre, Nijmegen, The Netherlands.
authors.forename: Tim L
authors.initials: TL
authors.lastname: Emmerzaal
authors.affiliation: Department of Anatomy, Radboud University Medical Centre, Nijmegen, The Netherlands; Hayward Genetics Center, Tulane University School of Medicine, New Orleans, Louisiana.
authors.forename: Tamas
authors.initials: T
authors.lastname: Kozicz
authors.affiliation: Department of Physiology, School of Biomedical and Psychological Sciences, Monash University, Clayton, Melbourne, Victoria, Australia. Electronic address: Zane.Andrews@monash.edu.
authors.forename: Zane B
authors.initials: ZB
authors.lastname: Andrews
mesh_terms: D000818:Animals; D025461:Feedback, Physiological; D054439:Ghrelin / Q000378:metabolism / Q000502:physiology*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism / Q000503:physiopathology*; D019964:Mood Disorders / Q000378:metabolism / Q000503:physiopathology*; D010913:Pituitary-Adrenal System / Q000378:metabolism / Q000503:physiopathology*; D013315:Stress, Psychological / Q000378:metabolism / Q000503:physiopathology*
chemical_list: D054439:Ghrelin
keywords: Centrally projecting Edinger-Westphal nucleus; Depression; Ghrelin; Hypothalamic-pituitary-adrenal axis; Paraventricular nucleus of the hypothalamus; Pituitary; Stress