Circular RNAs in early brain development and their influence and clinical significance in neuropsychiatric disorders

Neuropsychiatric disorders represent a set of severe and complex mental illnesses,and the exact etiologies of which are unknown.It has been well documented that impairments in the early development of the brain contribute to the pathogenesis of many neuropsychiatric disorders.Currently,the diagnosis of neuropsychiatric disorders largely relies on subjective cognitive assessment,because there are no widely accepted biochemical or genetic biomarkers for diagnosing mental illness.Circular RNAs (circRNAs) are a novel class of endogenous non-coding RNA (ncRNA) with a closed-loop structure.In recent years,there have been tremendous advances in our understanding of the expression profiles and biological roles of circRNAs.In the brain,circRNAs are particularly enriched and are expressed more abundantly in contrast to linear counterpart transcripts.They are highly active at neuronal synapses.These features make circRNAs uniquely crucial for understanding brain health,disease,and neuropsychiatric disorders.This review focuses on the role of circRNAs in early brain development and other brain-related processes that have been associated with the development of neuropsychiatric disorders.In addition,we discuss the potential for blood or cerebrospinal fluid circRNAs to be used as novel biomarkers in the early diagnosis of neuropsychiatric disorders.The findings reviewed here may provide new insight into the pathological mechanisms underlying the onset and progression of neuropsychiatric disorders.

Nonspecific Effect of Stress on Brain Gray Matter Volume in Drug-naive Female Patients with First Depressive Episode

Background： This study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events （SLEs） before the onset of depression.Methods： Forty-three drug-naive female patients voluntarily participated in the present study after the first major depressive episode.The life event scale was used to evaluate the severity of the impact of SLEs during 6 months before the onset of the major depressive episode.High-field magnetic resonance imaging （MRI） scans were obtained, and the VBM and SPM8 software process were used to process and analyze the MRI.Results： Compared to that in patients without SLEs, the volume of brain gray matter was lower in the bilateral temporal lobe, right occipital lobe, and right limbic lobe in the SLE group.However, the gray matter volume did not differ significantly between the two groups after the application of false discovery rate （FDR） correction.Conclusions： Although the results of the present study suggest the absence of significant differences in brain gray matter volume between female drug-naive patients after the first episode of major depression with and without SLEs after FDR correction, the study provides useful information for exploring the definitive role of stress in the onset of depression.

Exploring neuroimaging-genetic co-alteration features of auditory verbal hallucinations in different subjects for the establishment of a predictive model

To the Editor: Auditory verbal hallucination (AVH) is defined as the hearing of voices in the absence of any external auditory stimulus.[1,2,3] Most AVH content is related to the experiencer, and these events usually cause serious distress. AVHs can occur in patients with a broad range of mental disorders and neurological diseases, such as schizophrenia, bipolar disorder (BP), major depressive disorder (MDD), post-traumatic stress disorder (PTSD), borderline personality disorder (BPD), and in healthy individuals.[2,3,4]

Fieverse Postulation for ＂Disruption of Brain Networks＂ Hypothesis of Schizophrenia

To the Editor： In the previous two decades, increasing numbers of studies have used magnetic resonance imaging （MRI） techniques to investigate the brain characteristics of schizophrenia. These studies have produced important and useful achievements and enhanced our understanding of the mechanisms of schizophrenia from neural perspectives. We hope that in the future, researchers will discover additional milestone findings in this field to relieve the current bottleneck with respect to accurately determining the mechanisms of schizophrenia and identifying precise treatment targets or this disease, which is associated with high disability and mortality.