title: Catechol-O-methyltransferase activity in erythrocytes from patients with eating disorders.
abstract: OBJECTIVE
  Abnormal feeding has been linked to disruptions in brain dopaminergic activity and recent studies have assessed the role of catechol-O-methyltransferase (COMT) in eating disorders. This is the first study to quantify the soluble catechol-O-methyltransferase (S-COMT) activity in erythrocytes from patients with anorexia nervosa (AN), bulimia nervosa (BN) and binge-eating disorder (BED) and the first study at all to evaluate the COMT on patients with BED.
  
  
  METHODS
  Forty blood samples from patients with AN, BN and BED and healthy controls were drawn to evaluate S-COMT activity in erythrocytes by high-performance liquid chromatography and mass spectrometry. Since several patients were being treated with fluoxetine 20 mg, they were included in a different group (BN MED and BED MED). Liver homogenates from rats were used to evaluate baseline S-COMT activity in the presence of fluoxetine by the same in vitro procedures and assays.
  
  
  RESULTS
  Erythrocyte S-COMT activity (pmol/mg prt/h) was significantly increased in patients with BN and BED (41.3 ± 6.8 and 41.4 ± 14, respectively) compared to control group (25.3 ± 9.7). In fluoxetine-treated patients with BN, S-COMT activity (15.9 ± 8.8) was decreased compared to the other BN group; however, in BED group, the difference between BED MED and BED was not observed. In patients with AN, no significant difference was found compared to controls.
  
  
  CONCLUSIONS
  Patients with BN and BED presented higher S-COMT activity in erythrocytes, which is in agreement with previous studies on the literature addressing the high-activity COMT allele, Val158, as risk factor for eating disorders. Although in fluoxetine-treated patients with BN the activity of S-COMT was similar to the controls, this is not explained by a direct interaction between fluoxetine and S-COMT as verified in in vitro assays.
authors: Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal. tiagomab2@gmail.com.
authors: T
authors: T
authors: Amorim-Barbosa
authors: Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal.
authors: M P
authors: MP
authors: Serrão
authors: Psychiatry and Mental Health Clinic, São João Hospital-Medical Centre, Porto, Portugal.
authors: I
authors: I
authors: Brandão
authors: Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal.|Center for Drug Discovery and Innovative Medicines (MedInUP), University of Porto, Porto, Portugal.
authors: M A
authors: MA
authors: Vieira-Coelho
mesh_terms: D000818:Animals; D002394:Catechol O-Methyltransferase / Q000378:metabolism*; D004912:Erythrocytes / Q000201:enzymology*; D001068:Feeding and Eating Disorders / Q000201:enzymology*; D005260:Female; D006801:Humans; D008099:Liver / Q000201:enzymology; D008297:Male; D013058:Mass Spectrometry; D051381:Rats
chemical_list: D002394:Catechol O-Methyltransferase
keywords: Anorexia nervosa; Binge-eating disorder; Bulimia nervosa; Catechol-O-methyltransferase; Dopamine