Plasma amino acids profile in first-episode psychosis, unaffected siblings and community-based controls

• Published in: Scientific reports Vol. 10; no. 1; pp. 21423 - 11
• Main Authors: Loureiro, Camila Marcelino, da Roza, Daiane Leite, Corsi-Zuelli, Fabiana, Shuhama, Rosana, Fachim, Helene Aparecida, Simões-Ambrosio, Lívia Maria Cordeiro, Deminice, Rafael, Jordão, Alceu Afonso, Menezes, Paulo Rossi, Del-Ben, Cristina Marta, Louzada-Junior, Paulo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08.12.2020; Nature Publishing Group; Nature Portfolio
• Subjects: 631/378/340; 692/53; 692/699/476/1761; 692/699/476/1799; Adult; Amino acids; Amino Acids - blood; Antipsychotic Agents - therapeutic use; Antipsychotics; Body Mass Index; Case-Control Studies; Cross-Sectional Studies; Dopamine receptors; Drug therapy; Female; gamma-Aminobutyric Acid - blood; Gas chromatography; Gas Chromatography-Mass Spectrometry; Generalized linear models; Glutamatergic transmission; Glutamic acid; Glutamic Acid - blood; Glutamine; Glutamine - blood; Glycine; Glycine - blood; Humanities and Social Sciences; Humans; Linear Models; Male; Mass spectrometry; Mass spectroscopy; Mental disorders; multidisciplinary; Neurotransmitters; Plasma; Plasma levels; Proline; Proline - analysis; Psychosis; Psychotic Disorders - blood; Psychotic Disorders - drug therapy; Psychotropic drugs; Science; Science (multidisciplinary); Serine; Serotonin; Siblings; Tryptophan; Tryptophan - blood; Tyrosine; Young Adult; γ-Aminobutyric acid
• DOI: 10.1038/s41598-020-78559-w
• ISSN: 2045-2322

Investigations of plasma amino acids in early psychosis and their unaffected siblings are rare. We measured plasma amino acids involved in the co-activation of dopaminergic, GABAergic, glutamatergic, and serotoninergic neurotransmitters in first-episode psychosis (FEP) patients (n = 166), unaffected siblings (n = 76), and community-based controls (n = 166) included in a cross-sectional study. Plasma levels of glutamic acid (GLU), glutamine, glycine, proline (PRO), tryptophan (TRP), tyrosine, serine and GABA were quantified by gas-chromatography-mass spectrometry. We used the generalized linear model adjusted by sex, age, and body mass index for group comparison and paired t-test for FEP-Sibling pairs. FEP had reduced GABA plasma levels compared to siblings and controls (p < 0.05 for both). Siblings had lower GLU, Glx and PRO (p < 0.05 for all) but increased TRP compared to patients and controls (p < 0.05 for both). FEP patients with longer duration of pharmacological treatment and medicated only with antipsychotics had increased GLU compared to FEP with shorter periods, or with those treated with a combination of medications (p < 0.05 for both). Finally, FEP patients treated only with antipsychotics presented higher Glx compared to those with mixed medications (p = 0.026). Our study suggests that FEP have low a GABA plasma profile. Unaffected siblings may be a possible risk group for metabolic abnormalities.