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Background: Nucleus Accumbens (NAc) is a vital brain region for the process of reward and stress, whereas microRNA plays a crucial role in depression pathology. However, the abnormality of NAc miRNA expression during the stress-induced depression and antidepressant treatment, as well as its biological significance, are still unknown.Methods: We performed the small RNA-sequencing in NAc of rats from three groups: control, chronic unpredictable mild stress (CUMS), and CUMS with an antidepressant, Escitalopram. We applied an integrative pipeline for analyzing the miRNA expression alternation in different model groups, including differential expression analysis, co-expression analysis, as well as a subsequent pathway/network analysis to discover both miRNA alteration pattern and its biological significance.Result: A total of 423 miRNAs were included in analysis.18/8 differential expressing (DE) miRNA (adjusted p < 0.05, |log2FC| > 1) were observed in controls Vs. depression/depression Vs. treatment, 2 of which are overlapping. 78% (14/18) of these miRNAs showed opposite trends of alteration in stress and treatment. Two micro RNA, miR-10b-5p and miR-214-3p, appeared to be hubs in the regulation networks and also among the top findings in both differential analyses. Using co-expression analysis, we found a functional module that strongly correlated with stress (R = 0.96, P = 0.003), and another functional module with a moderate correlation with anhedonia (R = 0.89, P = 0.02). We also found that predicted targets of these miRNAs were significantly enriched in the Ras signaling pathway, which is associated with both depression, anhedonia, and antidepressant treatment.Conclusion: Escitalopram treatment can significantly reverse NAc miRNA abnormality induced by chronic stress. However, the novel miRNA alteration that is absent in stress pathology also emerges, which means that antidepressant treatment is unlikely to bring miRNA expression back to the same level as the controls. Also, the Ras-signaling pathway may be involved in explaining the depression disease etiology, the clinical symptom, and treatment response of stress-induced depression. [ABSTRACT FROM AUTHOR]

Abstracts Although many major breakthrough had identificated potential susceptibility genes for schizophrenia, the aetiology of schizophrenia is still unknown. In the present study, we focused on the N -methyl-Daspartate receptors related genes nitric oxide synthase 1 adaptor gene ( NOS1AP ), disrupted in schizophrenia 1 gene ( DISC1 ), d -amino acid oxidase activator gene ( DAOA ), and glycogen synthase kinase 3-beta gene ( GSK3B ). A family-based genetic association study (459 Han Chinese subjects in 153 nuclear families) using 3 single nucleotide polymorphisms in NOS1AP , 2 in DISC1 , 1 in DAOA and 1 in GSK3B was conducted. We found rs12742393 have just positive trend with schizophrenia (SCZ) (p = 0.07) after FDR correction. NOS1AP mRNA and serum levels were significantly elevated in SCZ patients (p < 0.001; p < 0.001) compared with healthy control. However, expression Quantitative Trait Loci (eQTL) analysis have demonstrated that rs12742393 genotype were not significantly associated with the NOS1AP mRNA expression. GMDR identified a significant seven-locus interaction model involving ( NOS1AP -rs348624, rs12742393, rs1415263, DISC1 -rs821633, rs1000731, DAOA -rs2391191and GSK3B - rs6438552) with a good testing accuracy (0.72). Our finding suggested statistically significant role of interaction of NOS1AP , DISC1 , DAOA , and GSK3B polymorphisms ( NOS1AP -rs348624, rs12742393, rs1415263, DISC1 -rs821633, rs1000731, DAOA -rs2391191and GSK3B -rs6438552) in EOS susceptibility. [ABSTRACT FROM AUTHOR]

Background: Subsyndromal 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) Method: With the help of the quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR), we gained gene relative expression levels among the three groups. Results: We 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. Conclusion: CD84, STRN, CTNS gene may have significant value for performing diagnostic functions and classifying SSD, MDD and healthy controls. [ABSTRACT FROM AUTHOR]

Accumulating evidence has implied that serotonin system dysfunction may be involved in the etiology of anorexia nervosa (AN). Serotonin-transporter-linked promoter region (5-HTTLPR) polymorphism is the genetic variant coding for the serotonin transporter and has a modulatory effect on its expression. This study aimed to investigate the possible association between the 5-HTTLPR and the susceptibility and severity of AN in Han Chinese using a case-control (255 patients and 351 controls) and family based study (198 trios). Eating disorder examination was used to measure the severity of AN behavioral symptoms. For the case-control study, the 5-HTTLPR showed significant association with AN in our sample (genotypic P = 0.03). The frequency of S allele was significantly higher in patients than that in controls (OR = 1.38, 95%CI: 1.06–1.79, P = 0.017). For the family-based study, the S allele of 5-HTTLPR was preferentially transmitted rather than non-transmitted from the parents to affected offspring (P = 0.013). The results of ANCOVA test revealed no significant association between the 5-HTTLPR polymorphism and severity of AN. Our findings suggested that 5-HTTLPR is able to confer susceptibility to AN in Han Chinese. [ABSTRACT FROM AUTHOR]

Rationale: In clinical practice, ketamine, an antagonist of the N-methyl- d-aspartate receptor (NMDAR), is used to alleviate depressive symptoms in patients with major depressive disorder (MDD), especially in those with treatment-resistant depression (TRD). Accordingly, the human gene coding for the 2B subunit of the NMDAR ( GRIN2B) is considered a promising candidate gene for MDD susceptibility. Objectives: The primary aim of this study is to examine whether potentially functional polymorphisms of GRIN2B confer risk for MDD, and second to investigate whether GRIN2B acts as a genetic predictor for TRD in MDD patients. Methods: We enrolled 178 TRD and 612 non-TRD patients as well as 779 healthy controls. Results: Four potentially functional polymorphisms (rs1805502, rs890, rs1806201, and rs7301328) within GRIN2B were genotyped in all participants. The haplotype analysis found significant differences in the distribution of the G-T haplotype between the TRD and control groups (corrected P = 0.007), and the frequency of the G-T haplotype in TRD group was significantly higher than that in the controls (TRD/control ratio 0.31:0.21). Statistically significant differences in allele and genotype frequencies were detected between TRD and non-TRD groups for the rs1805502 polymorphism within GRIN2B. There was a significant allelic association between rs1805502 and TRD with an excess of the G allele in the TRD group, compared to non-TRD group (OR = 1.55, 95 % CI = 1.18-2.05, corrected P = 0.008). Conclusions: These initial findings strengthen the hypothesis that GRIN2B not only confers susceptibility to TRD, but also plays a genetic predictor for TRD in MDD patients. [ABSTRACT FROM AUTHOR]

Abstract: Schizophrenia is one of highly heritable psychiatric disorders. Patients with early onset schizophrenia tend to have a greater genetic loading and may be an attractive subpopulation for genetics studies. A single nucleotide polymorphism (SNP) rs139887 in sex-determining region Y-box 10 (SOX10), a candidate gene for schizophrenia, was suggested to be associated with schizophrenia although inconsistent results had been reported. The aim of this study was to evaluate the association between SOX10 rs139887 polymorphism and schizophrenia using an early onset sample in the Chinese Han population. A total of 321 schizophrenic patients with onset before age 18 and 400 healthy controls were recruited for association study. In addition, two populations involved in three studies were selected for meta-analysis to determine the effect of rs139887 on schizophrenia. Our association study results showed that the allele and genotype frequencies were significantly different between schizophrenic patients and controls (P =0.013 and P =0.034, respectively). Interestingly, a significant association in allele and genotype frequencies were found in male patients (P =0.017 and P =0.045, respectively), but not female patients. Moreover, the C/C genotype had a significant association with an earlier age of onset in male schizophrenic patients (Kaplan–Meier log-rank test P =0.029), but not in female patients (Kaplan–Meier log-rank test P =0.876). The meta-analysis result showed the same C allele was significantly associated with schizophrenia (P =0.007). In conclusion, the SOX10 rs139887 polymorphism was related to the development of schizophrenia in a gender-specific manner, and may be a significant genetic marker for managing subgroups and etiological clues in schizophrenia. [Copyright &y& Elsevier]

Abstract: Decreased dopaminergic activity in the prefrontal cortex (PFC) has been consistently reported in schizophrenia patients. The dopamine D1 receptor (DRD1) plays an important role in mediating dopaminergic transmission in the PFC. Controversy about this topic still exists despite ample evidence suggesting that the DRD1 gene is associated with performance on neuropsychological tests probing the function of the PFC in schizophrenia, as well as positive and negative symptoms and therapeutic response to antipsychotics. To determine whether this gene is involved in the etiology of schizophrenia, we undertook a case–control study to look for an association. We genotyped five single nucleotide polymorphisms (SNPs) rs4532, rs5326, rs2168631, rs6882300 and rs267418 within the DRD1 involving 373 schizophrenia patients with early age of onset and 379 healthy subjects. No significant differences of genotype, allele or haplotype distribution were identified between patients and controls. Our results do not preclude a possible role of DRD1 in the etiology of schizophrenia. As an important dopaminergic gene, DRD1 may contribute to schizophrenia by interacting with other genes. Further relevant studies are warranted. [Copyright &y& Elsevier]

Abstract: Several lines of evidence have suggested that two functional methylenetetrahydrofolate reductase gene (MTHFR) polymorphisms, C677T and A1298C, may be implicated in the etiology of schizophrenia. We examined these MTHFR polymorphisms in 111 families, composed of a patient and their parents, as well as 143 mothers of patients with schizophrenia and 235 age-matched mothers who had healthy children. The maternal MTHFR 1298C allele was associated with a significantly increased risk of schizophrenia (OR=1.63, 95%CI: 1.11–2.39, P =0.01). The haplotype analysis showed a weak association for the 1298C-677C haplotype (OR=1.54, 95%CI=1.03–2.29, P =0.04). Analysis of Transmission Disequilibrium Test (TDT) showed no preferential transmission of 1298C and 677T alleles from parents to probands (P =0.64 and P =0.71, respectively). Our results suggest that deficient MTHFR enzyme activity in pregnant women, related to the A1298C variant, is associated with a higher risk of having offspring affected with schizophrenia. Given the low sample size in this study, the present results seem tentative and need further studies to replicate. [Copyright &y& Elsevier]