No abstract

BackgroundSubsyndromal symptomatic depression (SSD) is a subtype of subthreshold depressive and can lead to significant psychosocial functional impairment. Although the pathogenesis of major depressive disorder (MDD) and SSD still remains poorly understood, a set of studies have found that many same genetic factors play important roles in the etiology of these two disorders. Nowadays, the differential gene expression between MDD and SSD is still unknown. In our previous study, we compared the expression profile and made the classification with the leukocytes by using whole-genome cRNA microarrays among drug-free first-episode subjects with SSD, MDD and matched healthy controls (8 subjects in each group), and finally determined 48 gene expression signatures. Based on these findings, we further clarify whether these genes mRNA was different expressed in peripheral blood in patients with SSD, MDD and healthy controls (60 subjects respectively)MethodWith the help of the quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR), we gained gene relative expression levels among the three groups.ResultsWe found that there are three of the forty eight co-regulated genes had differential expression in peripheral blood among the three groups, which are CD84, STRN, CTNS gene (F = 3.528, p = 0.034; F = 3.382, p = 0.039; F = 3.801, p = 0.026, respectively) while there were no significant differences for other genes.ConclusionCD84, STRN, CTNS gene may have significant value for performing diagnostic functions and classifying SSD, MDD and healthy controls.

Background: Disturbances of microRNA-195 have been implicated in the pathogenesis of schizophrenia. However, microRNA-195 levels in schizophrenia are controversial. Aims: To the best of our knowledge, this is the first study to examine microRNA-195 levels in untreated schizophrenia patients and their relationship to olanzapine response. Methods: We recruited 81 untreated schizophrenia patients and 96 healthy controls. The patients received 2 months olanzapine treatment. MicroRNA-195 levels in peripheral blood mononuclear cells were measured using quantitative real-time polymerase chain reaction testing. Psychiatric symptoms were assessed using the Positive and Negative Syndrome Scale. Results: No significant differences in microRNA-195 levels were found between patients and healthy controls ( p > 0.05). Olanzapine significantly reduced microRNA-195 levels after 2 months treatment ( p = 0.003). Interestingly, microRNA-195 levels decreased significantly in responders ( p = 0.010), but not in non-responders ( p > 0.05). Both baseline microRNA-195 levels ( p = 0.027, p = 0.030) and the reduction rate of microRNA-195 levels ( p = 0.034, p = 0.044) were positively associated with the reduction rate of Positive and Negative Syndrome Scale total score and general psychopathological subscale score. Multiple stepwise regression analysis revealed that baseline microRNA-195 level was an independent contributor to the reduction in Positive and Negative Syndrome Scale total score and the general psychopathological subscale score ( p = 0.018, p = 0.030). Finally, logistic regression analysis suggested that baseline microRNA-195 level can serve as a biomarker for response to olanzapine ( p = 0.037). Conclusions: Our data indicate that microRNA-195 level may predict symptomatic improvement and olanzapine response in schizophrenia patients, suggesting that microRNA-195 should be considered as a potential therapeutic target for antipsychotics.