Anorexia nervosa (AN) is a disease that is caused by and persists due to a number of factors, including heredity, personal factors, and social circumstances. The change of many biologic indicators is caused as a secondary phenomenon by undernutrition. These changes can influence appetite and brain function. In this paper, genetic and biological indicators (biomarkers) associated with the symptoms of AN are summarized. 1) Psychic symptoms such as mood and anxiety : Changes in 5-HT (serotonin) activity, abnormality of the 5-HT gene receptor and BDNF (brain-derived neurotrophic factor). 2) Reward system : Abnormalities of cannabinoid receptor genes and dopamine related proteins and polymorphism of COMT (Catechol-0-methyltransferase). 3) Appetite control system : The effects of eating-related peptides complicated as a result of chronic starvation. Our data shows that the BMI values of chronic AN patients had a negative relation to "maturity fear" on psychological test and to desacyl ghrelin but not active ghrelin. Timing was different between nutritional improvement and the change of eating-related peptides during the recovery process of AN. 4) Metabolism and body composition : Dysfunction of beta-adrenergic receptors and UCP (uncoupling protein) as agents facilitating weight loss were noted. We reported that the body consumes fat mainly as an energy source under conditions of starvation at a BMI level of 13 kg/m^2 or more and that the supply of energy is converted from fat mass to FFA (fat free mass) at a BMI lower than 13 kg/m^2. We also report that the risk of urgent hospitalization due to physical factors increases as the BMI value and FFA volume decreases. Furthermore, for patients in a severely emaciated state of AN (<12.5kg/m^2), we found that FFA was predominantly synthesized and that BMR (basal metabolic rate) was inhibited during the period of increasing weight. The physical management is important to the improvement of the FFA, which is critical for patients at this stage.
|Translated title of the contribution
|Biomarker of Anorexia Nervosa(New Horizon of Eating Disorders)
|Number of pages
|Japanese Journal of Psychosomatic Medicine
|Published - 2012