Plasma peptidases as prognostic biomarkers in patients with first-episode psychosis

• Published in: Psychiatry research 2015-08, Vol.228 (2), p.197-202
• Main Authors: Fernández-Atucha, Ainhoa, Echevarría, Enrique, Larrinaga, Gorka, Gil, Javier, Martínez-Cengotitabengoa, Mónica, González-Pinto, Ana M, Irazusta, Jon, Seco, Jesús
• Format: Article
• Language: English
• Subjects: Adult; Aminopeptidases - blood; Aminopeptidases - metabolism; Biomarkers - blood; CD13 Antigens - blood; CD13 Antigens - metabolism; Clinical scales; Dipeptidyl Peptidase 4 - blood; Dipeptidyl Peptidase 4 - metabolism; Female; First-episode psychosis; Follow-Up Studies; GAF; HDRS; Humans; Male; Middle Aged; Peptide Hydrolases - blood; Peptide Hydrolases - metabolism; Plasma aminopeptidase; Prognosis; Psychiatric Status Rating Scales; Psychiatry; Psychotic Disorders - blood; Psychotic Disorders - diagnosis; Psychotic Disorders - psychology; Serine Endopeptidases
• ISSN: 0165-1781; 1872-7123
• DOI: 10.1016/j.psychres.2015.04.027

Abstract The plasma activity of nine aminopeptidases was monitored over a year in first-episode psychotic patients. We observed significant differences in aminopeptidase B (APB), aminopeptidase N (APN) and dipeptidyl peptidase IV (DPPIV), but not in puromycin-sensitive aminopeptidase (PSA), prolyl endopeptidase (PEP), cysteine aminopeptidase (Cys-AP), aspartate aminopeptidase (Asp-AP), glutamate aminopeptidase (Glu) or piroglutamate aminopeptidase (PGI) in these patients compared to controls, and also a progressive increase in plasma activity, correlated to changes in scores on clinical scales, Global Assessment of Functioning scale (GAF) and Hamilton Depression Rating Scale (HDRS), at 1 month of follow-up. At 1 month after diagnosis, the median score obtained by patients on the GAF was negatively associated with the plasma activity of APB and PEP measured at the beginning of the psychotic episode, indicating a role as a negative prognostic factor that can predict psychiatric symptomatology. In the case of HDRS, scores at 1 month after diagnosis were found to be positively associated with the initial plasma activity of DPPIV, APN and PSA, indicating that their initial elevation is a negative prognostic factor that can predict subsequent depressive symptomatology. Taken together, these results suggest a pathophysiological involvement of plasma peptidases and indicate that aminopeptidase activity can predict the course of first-episode psychosis patients, acting as a prognostic indicator.