Several theories have been proposed to explain the mechanisms of substance use in schizophrenia. Brain neurons pose a potential to provide novel insights into the association between opioid addiction, withdrawal, and schizophrenia. Thus, we exposed zebrafish larvae at 2 days post-fertilization (dpf) to domperidone (DPM) and morphine, followed by morphine withdrawal. Drug-induced locomotion and social preference were assessed, while the level of dopamine and the number of dopaminergic neurons were quantified. In the brain tissue, the expression levels of genes associated with schizophrenia were measured. The effects of DMP and morphine were compared to vehicle control and MK-801, a positive control to mimic schizophrenia. Gene expression analysis revealed that α1C, α1Sa, α1Aa, drd2a, and th1 were up-regulated after 10 days of exposure to DMP and morphine, while th2 was down-regulated. These two drugs also increased the number of positive dopaminergic neurons and the total dopamine level but reduced the locomotion and social preference. The termination of morphine exposure led to the up-regulation of th2, drd2a, and c-fos during the withdrawal phase. Our integrated data implicate that the dopamine system plays a key role in the deficits in social behavior and locomotion that are common in the schizophrenia-like symptoms and opioid dependence.
Transcription factor 4 (TCF4) gene plays an important role in nervous system development and it always associated with the risk of schizophrenia. Since miRNAs regulate targetgenes by binding to 3'UTRs of target mRNAs, the functional variants located in 3'UTR of TCF4 are highly suggested to affect the gene expressions in schizophrenia. To test the hypothesis regarding the effects of the variants located in 3'UTR of TCF4, we conducted an in silico analysis to identify the functional variants and their predicted functions. In this study, we sequenced the 3'UTR of TCF4 in 13 multiplex schizophrenia families and 14 control families. We found two functional variants carried by three unrelated patients. We determined that the C allele of rs1272363 and the TC insert of rs373174214 might suppress post- transcriptional expression. Secondly, we cloned the region that flanked these two variants into a dual luciferase reporter system and compared the luciferase activities between the pmirGLO-TCF4 (control), pmirGLO-TCF4-rs373174214 and pmirGLO-TCF4-rs1273263. Both pmirGLO-TCF4-rs373174214 and pmirGLO-TCF4-rs1273263 caused lower reporter gene activities, as compared to the control. However, only the C allele of rs1272363 reduced the luciferase activity significantly (p = 0.0231). Our results suggested that rs1273263 is a potential regulator of TCF4 expression, and might be associated with schizophrenia.
Depression is commonly observed in university students, who are a high risk group for developing psychiatric disorders during adulthood. This study aimed to determine the prevalence of depression and its traditional Chinese medicine body constitutions and psychological determinants among university students in Malaysia. A cross-sectional pilot study was conducted between 9 and 28 September 2020 among 80 university students in Malaysia. Participants completed online survey questionnaires, including the validated Patient Health Questionnaire (PHQ-9), Constitution in Chinese Medicine Questionnaire (CMCQ), Dysfunctional Attitude Scale (DAS), Depression Anxiety Stress Scale (DASS-21) stress subscale, Perceived Stress Scale (PSS-10), and Rosenberg Self-Esteem Scale (RSES), which assess depression, body constitution, dysfunctional attitude, stress, perceived stress, and self-esteem. Multiple linear regression analyses were performed to determine the associated risk factors for depression. The overall prevalence of depression among university students was 33.8%. The multiple regression analysis showed a significant relationship between depression and qi-stagnation constitution (B = 0.089, p = 0.011), balanced constitution (B = -0.077, p = 0.049), and self-esteem (B = -0.325, p = 0.001). Our findings suggest that some traditional Chinese medicine body constitutions and self-esteem are significant risk factors affecting depression among university students. Identifying risk factors of depression is vital to aid in the early detection of depression among university students.