Chiaki Ono

Therapeutic concentration of lithium stimulates complement C3 production in dendritic cells and microglia via GSK‐3 inhibition

Evidence indicates that widely prescribed mood stabilizer, lithium (Li), mediates cellular functions of differentiated monocytic cells, including microglial migration, monocyte‐derived dendritic cell (MoDC) differentiation, and amelioration of monocytic malfunctions observed in neuropsychiatric diseases. Here, we surveyed molecules which take major roles in regulating these monocytic cellular functions. MoDCs treated with 1 and 5 mM Li, and microglia separated from Li‐treated mice were subjected to microarray‐based comprehensive gene expression analyses. Findings were validated using multiple experiments, including quantitative PCR, ELISA and immunostaining studies. Differing effects of Li on the two cell types were observed. Inflammation‐ and chemotaxis‐relevant genes were significantly over‐represented among Li‐induced genes in MoDCs, whereas no specific category of genes was over‐represented in microglia. The third component of complement (C3) was the only gene which was significantly induced by a therapeutic concentration of Li in both MoDCs and microglia. C3 production was increased by Li via GSK‐3 inhibition. Li‐induced C3 production was seen only in differentiated monocytic cells, but not in circulating monocytes. Our findings highlight a link between Li treatment and C3 production in differentiated monocytic cells, and reveal a regulatory role of GSK‐3 in C3 production. Induction of microglial C3 production might be a novel neuroprotective mechanism of Li via regulating interactions between microglia and neurons. GLIA 2015;63:257–270

Four mood stabilizers commonly induce FEZ1 expression in human astrocytes.

Yu Z, Ono C, Kim HB, Komatsu H, Tanabe Y, Sakae N, Nakayama KI, Matsuoka H, Sora I, Bunney WE, Tomita H. Four mood stabilizers commonly induce FEZ1 expression in human astrocytes. Bipolar Disord 2011: 13: 486–499.

Cognitive and neural correlates of the 5-repeat allele of the dopamine D4 receptor gene in a population lacking the 7-repeat allele

The 5-repeat allele of a common length polymorphism in the gene that encodes the dopamine D4 receptor (DRD4) is robustly associated with the risk of attention deficit hyperactivity disorder (ADHD) and substantially exists in Asian populations, which have a lower ADHD prevalence. In this study, we investigated the effect of this allele on microstructural properties of the brain and on its functional activity during externally directed attention-demanding tasks and creative performance in the 765 Asian subjects. For this purpose, we employed diffusion tensor imaging, N-back functional magnetic resonance imaging paradigms, and a test to measure creativity by divergent thinking. The 5-repeat allele was significantly associated with increased originality in the creative performance, increased mean diffusivity (the measure of how the tissue includes water molecules instead of neural and vessel components) in the widespread gray and white matter areas of extensive areas, particularly those where DRD4 is expressed, and reduced task-induced deactivation in the areas that are deactivated during the tasks in the course of both the attention-demanding working memory task and simple sensorimotor task. The observed neural characteristics of 5-repeat allele carriers may lead to an increased risk of ADHD and behavioral deficits. Furthermore, the increased originality of creative thinking observed in the 5-repeat allele carriers may support the notion of the side of adaptivity of the widespread risk allele of psychiatric diseases.

The associations among the dopamine D2 receptor Taq1, emotional intelligence, creative potential measured by divergent thinking, and motivational state and these associations' sex differences

Previous neuroscientific studies have shown that the dopaminergic system plays an important role in creative potential measured by divergent thinking (CPMDT), emotional control, and motivational state. However, although associations between two of these four components have been previously established (e.g., the association between CPMDT and emotional control, the association between CPMDT and motivational state, etc.), the interactions between these four remain unknown. The purpose of this study was to reveal these interactions using path analyses. The Taq1A polymorphism of the dopamine D2 receptor (DRD2) gene was used for this purpose. For measuring emotional intelligence (EI), we used the Japanese version of the Emotional Intelligence Scale. CPMDT was measured using the S-A creativity test. Motivational state was measured using the Vigor subscale of the Japanese version of the Profile of Mood Scale (POMS). Data from 766 healthy, right-handed individuals (426 men and 340 women; 20.7 ± 1.9 years of age) were used in this study. There were significant and robust positive relationships among measures of CPMDT, EI, and motivational state across sex. In addition, the polymorphism of the DRD2 gene was significantly associated with EI, specifically in females. Path analysis in females indicates that the model in which (a) the DRD2 polymorphism primarily facilitates EI, (b) EI in turn facilitates CPMDT and leads to a better motivational state, and (c) a better motivational state also directly facilitates CPMDT explains the data in the most accurate manner. This study suggested a comprehensive picture of the cascade of the associations among dopamine, EI, motivational state, and CPMDT at least in females.

Microglial production of TNF-alpha is a key element of sustained fear memory.

The proinflammatory cytokine productions in the brain are altered in a process of fear memory formation, indicating a possibility that altered microglial function may contribute to fear memory formation. We aimed to investigate whether and how microglial function contributes to fear memory formation. Expression levels of M1- and M2-type microglial marker molecules in microglia isolated from each conditioned mice group were assessed by real-time PCR and immunohistochemistry. Levels of tumor necrosis factor (TNF)-α, but not of other proinflammatory cytokines produced by M1-type microglia, increased in microglia from mice representing retention of fear memory, and returned to basal levels in microglia from mice representing extinction of fear memory. Administration of inhibitors of TNF-α production facilitated extinction of fear memory. On the other hand, expression levels of M2-type microglia-specific cell adhesion molecules, CD206 and CD209, were decreased in microglia from mice representing retention of fear memory, and returned to basal levels in microglia from mice representing extinction of fear memory. Our findings indicate that microglial TNF-α is a key element of sustained fear memory and suggest that TNF-α inhibitors can be candidate molecules for mitigating posttraumatic reactions caused by persistent fear memory.

The VEGF gene polymorphism impacts brain volume and arterial blood volume

Vascular endothelial growth factor (VEGF) plays a critical role in the angiogenesis and proliferation of various types of cells such as neurons, astroglia, and endothelial cells in the brain. A common polymorphism in the VEGF gene (−2578 C/A) is associated with circulating VEGF levels, cancers and Alzheimers disease. Nonetheless, the effects of this polymorphism on normal human brain volume, arterial blood volume, and blood supply remain unclear. In this study, the effects of this polymorphism on the total gray matter volume (TGMV) and total white matter volume (TWMV) using T1‐weighted structural images and the total arterial blood volume (TABV) and mean cerebral blood flow (mCBF) during rest using arterial spin labeling (ASL) in 765 young adult humans were investigated. Voxel‐by‐voxel whole‐brain analyses of these measures were also performed. Multiple regression analyses with age and sex as covariates revealed that the VEGF genotype (number of C alleles) was significantly and positively correlated with TGMV, TWMV, and TABV as well as with regional gray and white matter volumes in widespread areas and regional arterial blood volume in some areas with high arterial blood volume. However, these regional associations were not seen when the corresponding global signal was included as a covariate in the multiple regression analyses, indicating that we failed to obtain evidence of region‐specific associations between these brain measures and the genotype. The results suggest that the VEGF‐2578C allele, is associated with changes in the vascular system that lead to increased blood volume and larger brain volume. Hum Brain Mapp 38:3516–3526, 2017.

Fluorescently Activated Cell Sorting Followed by Microarray Profiling of Helper T Cell Subtypes from Human Peripheral Blood

Background Peripheral blood samples have been subjected to comprehensive gene expression profiling to identify biomarkers for a wide range of diseases. However, blood samples include red blood cells, white blood cells, and platelets. White blood cells comprise polymorphonuclear leukocytes, monocytes, and various types of lymphocytes. Blood is not distinguishable, irrespective of whether the expression profiles reflect alterations in (a) gene expression patterns in each cell type or (b) the proportion of cell types in blood. CD4+ Th cells are classified into two functionally distinct subclasses, namely Th1 and Th2 cells, on the basis of the unique characteristics of their secreted cytokines and their roles in the immune system. Th1 and Th2 cells play an important role not only in the pathogenesis of human inflammatory, allergic, and autoimmune diseases, but also in diseases that are not considered to be immune or inflammatory disorders. However, analyses of minor cellular components such as CD4+ cell subpopulations have not been performed, partly because of the limited number of these cells in collected samples. Methodology/Principal Findings We describe fluorescently activated cell sorting followed by microarray (FACS–array) technology as a useful experimental strategy for characterizing the expression profiles of specific immune cells in the circulation. We performed reproducible gene expression profiling of Th1 and Th2, respectively. Our data suggest that this procedure provides reliable information on the gene expression profiles of certain small immune cell populations. Moreover, our data suggest that GZMK, GZMH, EOMES, IGFBP3, and STOM may be novel markers for distinguishing Th1 cells from Th2 cells, whereas IL17RB and CNTNAP1 can be Th2-specific markers. Conclusions/Significance Our approach may help in identifying aberrations and novel therapeutic or diagnostic targets for diseases that affect Th1 or Th2 responses and elucidating the involvement of a subpopulation of immune cells in some diseases.

Polymorphisms in the microglial marker molecule CX3CR1 affect the blood volume of the human brain: Imaging genetics of CX3CR1 in the brain

CX3CR1, a G‐protein‐coupled receptor, is involved in various inflammatory processes. Two non‐synonymous single nucleotide polymorphisms, V249I (rs3732379) and T280M (rs3732378), are located in the sixth and seventh transmembrane domains of the CX3CR1 protein, respectively. Previous studies have indicated significant associations between T280M and leukocyte functional characteristics, including adhesion, signaling, and chemotaxis, while the function of V249I is unclear. In the brain, microglia are the only proven and widely accepted CX3CR1‐expressing cells. This study aimed to specify whether there were specific brain regions on which these two single nucleotide polymorphisms exert their biological impacts through their functional effects on microglia.

A common CACNA1C gene risk variant has sex-dependent effects on behavioral traits and brain functional activity

Genome-wide association studies have suggested that allelic variations in the CACNA1C gene confer susceptibility to schizophrenia and bipolar disorder only in women. Here we investigated the sex-specific effects of the CACNA1C variant rs1024582 on psychiatry-related traits, brain activity during tasks and rest, and brain volume in 1207 normal male and female subjects. After correcting for multiple comparisons, there were significant interaction effects between sex and the minor allele of this polymorphism on the hostile behavior subscale scores of the Coronary-Prone Type Scale mediated by higher scores in female carriers of the minor allele. Imaging analyses revealed significant interaction effects between sex and the minor allele on fractional amplitude of low-frequency fluctuations in the right dorsolateral prefrontal cortex and on brain activity during the 2-back task in areas of the right posterior cingulate cortex, right thalamus, and right hippocampus, which were all mediated by reduced activity in female carriers of the minor allele. Our results demonstrated that the rs1024582 risk variant of CACNA1C is associated with reduced activity in the frontolimbic regions at rest and during a working memory task as well as with greater hostility in females in the healthy population.

FACS-microarray study of immune cells from patients with schizophrenia

Schizophrenia is a severe psychiatric disorder with a worldwide prevalence of about 1%. Multiple independent studies based on cytokine measurements indicate a shift from Th1-like to Th2-like immune reactivity. However, the molecular bases of the shift in immune cells observed in schizophrenic patients remain unclear. In order to determine molecular bases of the shift in helper T cells, and the involvement into the pathogenesis of schizophrenia, we developed a research system to evaluate comprehensive gene expression profiles of Th1 and Th2 cells using fluorescence-activated cell sorting and microarray technologies. After obtaining written informed consent following the IRB-approved protocol, peripheral blood lymphocytes from 18 patients with schizophrenia and 18 control subjects were collected by Ficoll differential centrifugation. Lymphocytes were stained with anti-CD4-FITC, CXCR3-APC, CCR45-PE. Th1 (CD4+/CXCR3+) and Th2 (CD4+/CCR4+) cell sorting experiments were performed using FACS Aria. Extracted total RNA sample from each cell was amplified and applied on Illumina Human-6v2 BeadChips to analyze global changes in genome-wide mRNA expression levels. FACSarray gene expression profiling determined 223 increased and 586 decreased genes in Th1 helper T cells, and 87 increased and 108 decreased genes in Th2 helper T cells from schizophrenic patients, compared to control subjects. Genes dysregulated in Th1 genes of schizophrenic patients contain zinc finger genes and biopolymer modification related genes. Genes dysregulated in Th2 genes of schizophrenic patients include telomere maintenance related genes and chromosomal protein coding genes. These genes may be relevant to the Th1/Th2 imbalance observed in schizophrenic patients, and the pathophysiology of the disease.