Brief report Neurotransmitter receptor and regulatory gene expression in peripheral blood of Brazilian drug-naïve first-episode psychosis patients before and after antipsychotic treatment Vanessa Kiyomi Ota a,b,1 , Cristiano Noto b,1 , Ary Gadelha b , Marcos Leite Santoro a,b , Patricia Natalia Silva a,b , Maria Isabel Melaragno a , Marília de Arruda Cardoso Smith a , Quirino Cordeiro c , Rodrigo Affonseca Bressan b , Sintia Iole Belangero a,b,n a Disciplina de Genética, Departamento de Morfologia e Genética, Universidade Federal de Sao Paulo (UNIFESP), Rua Botucatu, 740, Edifício Leitao da Cunha, 11 andar, CEP 04023-900, São Paulo, Brazil b LiNC-Laboratório Interdisciplinar de Neurociências Clínicas, Departamento de Psiquiatria, Universidade Federal de Sao Paulo (UNIFESP), Rua Pedro de Toledo, 669, 31 andar fundos, CEP 05039-032, São Paulo, Brazil c Departamento de Psiquiatria, Irmandade da Santa Casa de Misericórdia de São Paulo (ISCMSP), São Paulo, Brazil article info Article history: Received 20 June 2013 Received in revised form 29 August 2013 Accepted 16 September 2013 Keywords: Schizophrenia GABRR2 CHRNA3 abstract Little is known about how genes expressed in blood relate to schizophrenia or antipsychotic use. We analyzed gene expression in 10 first-episode psychosis patients and nine controls using PCR Arrays. GABRR2 and CHRNA3 were found to be differentially expressed after risperidone treatment. These genes may be regulated by antipsychotic use. & 2013 Elsevier Ireland Ltd. All rights reserved. 1. Introduction The psychotic symptoms of schizophrenia (SCZ) usually arise during late adolescence and early adulthood (Onwumere et al., 2011). The first 5 years of the disorder are particularly critical (Birchwood et al., 1998), and several studies have shown that most deficits develop during this time frame (Ho et al., 2003). Investiga- tion of patients during their first episode of psychosis (FEP), particularly before they start taking any antipsychotic medication, is likely to be helpful for disentangling the biological underpinnings of disease onset, progression, and of the effects of antipsychotic therapy. Several studies have investigated gene expression changes in post-mortem samples from schizophrenic patients (for review, see Sequeira et al., 2012). However, post-mortem gene expression studies in prolonged illnesses are skewed by numerous factors, including illness duration and the effects of long-term medication exposure (Sequeira et al., 2012). To overcome these problems, gene expression analysis of peripheral blood has been proposed (Middleton et al., 2005; Takahashi et al., 2010; Lee et al., 2012), as blood shares similarities with multiple brain regions at the transcriptional level (Sullivan et al., 2006). Lymphocytes express several neurotransmitter receptors (Gladkevich et al., 2004), therefore we chose the Human Neuro- transmitter Receptors and Regulators RT 2 Profiler™ PCR Array System (PAHS-060; Qiagen, Germantown, MD), which includes schizophrenia-related genes such as DRD2 and COMT, to perform an expression profiling study comparing: (1) drug-naïve FEP patients and healthy subjects; and (2) drug-naïve FEP patients before and after treatment with antipsychotic drugs. Our study, which analyzes drug-naïve patients at multiple time points, may help to identify markers for the etiology of psychosis and the effects of antipsychotic treatment. Few prior studies have investi- gated drug-naïve FEP patients in a follow-up design (Zhang et al., 2008; Kuzman et al., 2009; Kumarasinghe et al., 2013). Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/psychres Psychiatry Research 0165-1781/$ - see front matter & 2013 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.psychres.2013.09.016 n Corresponding author at: Disciplina de Genética/UNIFESP, Rua Botucatu, 740, Ed. Leitao da Cunha, 11 andar, CEP 04023-900 Sao Paulo, Brazil. Tel.: þ5511 5576 4260, þ5511 5576 4264. E-mail addresses: vanessakaota@gmail.com (V.K. Ota), csnoto@gmail.com (C. Noto), aryararipe@yahoo.com.br (A. Gadelha), santorogen@gmail.com (M.L. Santoro), patriciaoliveira.unifesp@gmail.com (P.N. Silva), melaragno.morf@epm.br (M.I. Melaragno), macsmith.morf@epm.br (M.A.C. Smith), qcordeiro@yahoo.com (Q. Cordeiro), rodrigoabressan@gmail.com (R.A. Bressan), sinbelangero@gmail.com (S.I. Belangero). 1 Both authors contributed equally to this work. Psychiatry Research 210 (2013) 1290–1292