Emerging Roles of Non-coding RNAs on Symptom Type and Cognitive Functions in Schizophrenia and Schizoaffective Disorder.

OBJECTIVE

The study was designed to compare the expression levels of IL-6 mRNA, long non-coding RNA (lncRNA) NRON (non-coding repressor of the nuclear factor of activated T cells [NFAT]) and TMEVPG1 (Theiler's murine encephalomyelitis virus persistence candidate gene 1) which play critical roles in the regulation of immune function, and to investigate relationship between expression levels and symptom type and the cognitive functions in patients with schizophrenia and schizoaffective disorder.

METHODS

The study included 84 participants (27 patients with schizophrenia, 27 with schizoaffective disorder, and 30 healthy subjects). The lncRNA (TMEVPG1 and NRON) and IL-6 mRNA expression analysis was measured with the real-time PCR method. The Wisconsin Card Sorting Test, the Stroop Test, Clinical Global Impression Scale, Positive and Negative Symptoms Scale, Young Mania Rating Scale and the Hamilton Depression Rating Scale were applied.

RESULTS

The lncRNA TMEVPG1 expression level was determined to be higher in the patient groups than controls. The TMEVPG1 was able to differentiate schizophrenia cases from the controls. In the schizoaffective group, a positive correlation was determined between NRON expression and positive symptomatology, and an increase in NRON expression was determined to make a moderate contribution to cognitive dysfunction. NRON expression was decreased as the dose of antipsychotic drug increased in the schizophrenia group.

CONCLUSION

The results of this study demonstrated that there are significant differences between schizophrenia and schizoaffective disorder in terms of inflammatory markers and their relationship between the symptom type or cognitive functions.