Expression pattern of long non-coding RNAs in treatment-naïve and medicated schizophrenia patients

Schizophrenia is a disabling mental disorder that affects 1% of people over their lifetime. The etiology and mechanism of schizophrenia are very complex, and many genes are involved in many different signaling pathways in the etiology of this disease. According to recent studies, one of the important mechanisms altered in this disorder is the regulation of immune system and the inflammation mechanism. In the present study, we evaluated the peripheral blood expression pattern of four lncRNAs and three protein-coding genes in the treatment- naïve patients, and medicated patients compared with sex and age-matched controls. In the medicated-patients, expression levels of IFNG, IL18RAP, AC007278.2 were significantly up-regulated (P < 0.05); and the expression level of IFNG-AS1-001 was significantly down-regulated compared to healthy controls (P < 0.05). However, levels of IL18R1, AC007278.3 and IFNG-AS1-003 were not different between these groups. In the treatment-naïve patients, IFNG, IL18R1, IL18RAP, IFNG-AS1-001, AC007278.2, and AC007278.3 were significantly up-regulated compared to controls. On the other hand, IFNG-AS1-003 was significantly down-regulated in the treatment-naïve patients compared to controls. Based on the Spearman correlation matrix, there was a significant correlation between genes in the treatment-naïve patients. We also showed the high sensitivity and specificity of IFNG-AS1-003, IFNG, IL18R1, and AC007278.3 in the identification of treatment-naïve patients from controls. The current study contributes further evidence to the understanding of the role of lncRNAs in the pathogenesis of schizophrenia. Future research is necessary to establish the validity of lncRNAs as peripheral markers for this condition.