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Cutamesine, a sigma-1 receptor agonist, functions in both neuroprotection and neurite outgrowth. We assessed the therapeutic effects of cutamesine in a rodent spinal cord injury (SCI) model to demonstrate pre-clinical proof-of-concept. First of all, in order to determine optimal cutamesine dose, cutamesine was administered to normal rats and BDNF protein levels in the lumbar spinal cord were assessed by Western blot. Next, for the SCI model, spinal cords of adult female Sprague-Dawley rats were contused using an Infinite Horizon Impactor. Two weeks post-injury, rats were randomly assigned to receive daily subcutaneous injections of either cutamesine (3.0 mg/kg/day) or saline (as a control) for another two weeks. Immunohistochemistry for BDNF and 5-HT was assessed at four and twelve weeks post-injury in the lumbar spinal cord. Locomotor function was assessed weekly using the BBB locomotor scale until twelve weeks after SCI and CatWalk XT 10.5 gait analysis was conducted at twelve weeks after SCI. In normal rats, cutamesine treatment (3.0 mg/kg/day) significantly up-regulated BDNF expression in the lumbar spinal cord. In SCI rats, cutamesine treatment (3.0 mg/kg/day) significantly increased the fluorescence intensity of neuronal BDNF and serotonin boutons in the injured spinal cord compared to saline. However, cutamesine treatment did not promote significant locomotor recovery. Recent work indicates that cutamesine treatment alone did not promote locomotor recovery in spite of immunohistological changes. Future work will explore the influence of combining cutamesine with other treatment promoting plasticity (e.g. rehabilitative training) in SCI rats., (Copyright © 2021. Published by Elsevier B.V.)

Synphilin-1, a cytoplasmic protein, interacts with α-synuclein which is one of the main constituents of Lewy bodies and plays an important role in the pathology of Parkinson's disease (PD), in neurons. This interaction indicates that synphilin-1 may also play a central role in PD. However, the biological functions of synphilin-1 are not fully understood, and whether synphilin-1 is neurotoxic or neuroprotective remains controversial. This study examined the function of synphilin-1 in a PD model in vitro. We used an inhibitor of mitochondrial complex I, 1-methyl-4-phenylpyridinium (MPP + ). We established human neuroblastoma SH-SY5Y cell lines that stably expressed human synphilin-1. We found that overexpression of synphilin-1 increased SH-SY5Y cell viability after MPP + treatment. We further found that synphilin-1 significantly suppressed apoptotic changes in nuclei, including nuclear condensation and fragmentation, after MPP + treatment. We showed that synphilin-1 significantly decreased MPP + -induced cleaved caspase-3 and cleaved poly-ADP-ribose polymerase levels by using western blotting. Production of reactive oxygen species (ROS) induced by MPP + was significantly reduced in cells expressing synphilin-1 compared to those expressing empty vector. Synphilin-1 inhibited MPP + -induced cytochrome c release from mitochondria into the cytosol. These data suggested that synphilin-1 may function to protect against dopaminergic cell death by preserving mitochondrial function and inhibiting early steps in the intrinsic apoptotic pathway. Taken together, our results indicated that synphilin-1 may play neuroprotective roles in PD pathogenesis by inhibiting ROS production and apoptosis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Disturbances of the circadian rhythm are involved in the pathophysiology of bipolar disorder (BD), schizophrenia (SCZ) and major depressive disorder (MDD). Specifically, because clock gene dysfunction is good candidate for enhancing the susceptibility to these psychiatric disorders, we selected two circadian rhythm-related genes (CSNK1D and CSNK1E) and investigated genetic associations of the genes with these three disorders. None of the SNPs showed a significant association with MDD, but a SNP (rs2075984) in CSNK1E and SNP (rs6502097) in CSNK1D were associated with SCZ (P=0.0091, uncorrected) and BD (P=0.030, uncorrected), respectively. To confirm these findings, we analyzed an independent dataset (maximum N=3815) but found a lack of association (P=0.63 for rs2075984 and P=0.61 for rs6502097). The final meta-analysis showed no association between these SNPs with SCZ (P=0.21) and BD (P=0.53). These results do not support that genetic variation in CSNK1D and CSNK1E is a susceptibility factor for major psychiatric disorders in the Japanese population., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Near-infrared spectroscopy (NIRS) has proven to be useful for the evaluation of language lateralization in healthy subjects, infants, and epileptic patients. This study for the first time investigated the expressive and receptive language functions separately, using NIRS in presurgical glioma patients. We also describe a special case with dissociated pattern of language functions. Ten glioma patients were examined. Using NIRS, the hemodynamic changes during a verb generation task or story listening task were measured in the cerebral hemisphere on either side covering the language areas. Following the NIRS study, the Wada test was performed in all the patients. The NIRS study revealed increases of oxyhemoglobin and decreases of deoxyhemoglobin in the language areas elicited by both tasks. In 9 patients, who were all right-handed, the expressive and receptive language functions were lateralized to the left hemisphere. The results of the NIRS study were completely consistent with those of the Wada test. In the remaining 1 patient with a right sided insular glioma, who was right-handed, the NIRS study revealed stronger activation of the right inferior frontal region during the verb generation task, and stronger activation of the left superior temporal region during the story listening task. This dissociated language function was validated by the Wada test and the postoperative neurological course. These results demonstrate that a NIRS study using our technique is extremely valuable for preoperative assessment of the language functions and exemplifies how a preoperative NIRS study can allow detection of unforeseen language lateralization., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

The paired box 6 (PAX6) is a transcription factor expressed early in development, predominantly in the eye, brain and pancreas. Mutations in PAX6 are responsible for eye abnormalities including aniridia, and it is also known that some PAX6 mutations result in autism with incomplete penetrance. We resequenced all the exons and flanking introns of PAX6 in 285 autistic patients in the Japanese, with the possibility that novel mutations may underlie autism. Fifteen different polymorphisms were identified: 13 are novel, and 2 were previously reported (rs667773 and rs3026393). Among the novel ones, there is one missense mutation that was found in a patient: 136C>G (Leu46Val) (single nucleotide polymorphism ID "ss130452457" is temporarily assigned). Leu46 is extremely conserved from fly to human, and we did not detect Val46 in 2120 nonautistic subjects. The autistic patient carrying this heterozygous mutation showed reduced vision, photophobia and eyelid ptosis, but no other ocular abnormality such as aniridia. Our findings suggest the necessity of further studies on the causal relationship between PAX6 and autism.

In the adult rodent brain, constitutive neurogenesis occurs in two restricted regions, the subventricular zone (SVZ) of the lateral ventricle and the subgranular zone of the hippocampal dentate gyrus, where multipotent neural stem/progenitor cells generate new neurons. Using Western blotting and immunohistochemistry for established markers, we demonstrated that the expression of 3-phosphoglycerate dehydrogenase (Phgdh), an enzyme involved in de novo synthesis of l-serine, was upregulated in the SVZ. The expression was selective to cells having morphological features and expressing markers of astrocyte-like primary neural stem cells (type B cells) and their progeny, actively proliferating progenitors (type C cells). By contrast, Phgdh protein expression was virtually absent in committed neuronal precursors (type A cells) derived from type C cells. High levels of Phgdh were also expressed by glial tube cells located in the rostral migratory stream (RMS). Interestingly, ensheathment of type A cells by these Phgdh-expressing cells was persistent in the SVZ and RMS, suggesting that l-serine mediates trophic support for type A cells via these glial cells. In vitro neurosphere assays confirmed that growth-factor-responsive, transient amplifying neural progenitors in the SVZ, but not differentiated neurons, expressed Phgdh. In the aged brain, a decline in Phgdh expression was evident in type B and C cells of the SVZ. These observations support the notion that availability of l-serine within neural stem/progenitor cells may be a critical factor for neurogenesis in developing and adult brain.

Fisetin (3,3',4',7-tetrahydroxyflavone) has been found to be neuroprotective, induce neuronal differentiation, enhance memory, and inhibit the aggregation of the amyloid beta protein (Abeta) that may cause the progressive neuronal loss in Alzheimer's disease. The diverse collection of biological activities of this compound may lead to a new type of therapeutic drug for Alzheimer's disease. As the first step to design even more effective drugs based upon the structure of fisetin, the present study investigated the structural requirements for the anti-amyloidogenic activity of fisetin by comparing the effects of several structurally related flavonoids on Abeta fibril formation in vitro. Abeta1-42 (20muM) and the flavonoids were incubated for 0-48h at 37 degrees C, and fibril formation was quantitatively determined by the thioflavin T fluorescence assay. Among ten flavonoids tested, fisetin, 3',4',7-trihydroxylflavone, 3,3',4'-trihydroxyflavone, luteolin, quercetin and myricetin inhibited Abeta fibril formation. On the other hand, 3,3',7-trihydroxyflavone, 5-deoxykaempferol, chrysin and kaempferol enhanced Abeta fibril formation. These results suggest that the 3',4'-dihydroxyl group, but not the 3- or 7-hydroxyl group, is essential for the inhibitory effect of fisetin on Abeta fibril formation.

Disrupted in schizophrenia 1 (DISC1) and its molecular cascade are implicated in the pathophysiology of schizophrenia and bipolar disorder. As interacting-proteins with DISC1, Nudel, ATF4, ATF5, LIS1, alpha-tubulin, PDE4B, eIF3, FEZ1, Kendrin, MAP1A and MIPT3 were identified. We previously showed the down-regulation of ATF5 in the lymphoblastoid cells derived from affected co-twin of monozygotic twins discordant for bipolar disorder. We also suggested the contribution of endoplasmic reticulum stress response pathway to the illness, and ATF4 is one of major components in the pathway. Truncated mutant DISC1 reportedly cannot interact with ATF4 and ATF5. These findings suggest the role of these genes in the pathophysiology of bipolar disorder. In this study, we tested genetic association of ATF4 and ATF5 genes with bipolar disorder by a case-control study in Japanese population (438 patients and 532 controls) and transmission disequilibrium test in 237 trio samples from NIMH Genetics Initiative Pedigrees. We also performed gene expression analysis in lymphoblastoid cells. We did not find any significant association in both genetic study and expression analysis. By the exploratory haplotype analysis, nominal association of ATF4 with bipolar II patients was observed, but it was not significant after correction of multiple testing. Contribution of common variations of ATF4 and ATF5 to the pathophysiology of bipolar disorder may be minimal if any.

D-Serine is an endogenous coagonist that increases the opening of N-methyl-D-aspartate (NMDA)-type glutamate receptor channels. We previously reported a reduction of D-serine serum levels in schizophrenia, supporting the disease hypothesis of NMDA receptor-mediated hypo-neurotransmission. The serum levels of D-serine are thought to reflect brain d-serine content. It is important to understand whether there is a direct link between the altered D-serine levels and NMDA receptor expression in vivo or whether these are independent processes. Two polymorphisms are known to regulate the expression of NMDA receptor subunit genes: (GT)(n) (rs3219790) in the promoter region of the NR2A subunit gene (GRIN2A) and -200T > G (rs1019385) in the NR2B gene (GRIN2B). These polymorphisms are also reported to be associated with schizophrenia. Therefore, we examined the correlation between these two polymorphisms and d-serine serum levels in mentally healthy controls, schizophrenics and the combined group. We observed no significant genotype-phenotype correlations in any of the sample groups. However, analyses of larger sample numbers and the detection of additional polymorphisms that affect gene expression are needed before we can conclude that NMDA receptor expression and serum levels of d-serine, if involved in schizophrenia pathophysiology, are independent and additive events.

Dysfunction of the N-methyl-D-aspartate (NMDA) type glutamate receptor has been proposed as a mechanism in the etiology of schizophrenia. Recently, we identified a variable (GT)n repeat in the promoter region of the NMDA NR2A subunit gene (GRIN2A), and showed its association with schizophrenia in a case-control study, together with a correlation between the length of the repeat and severity of chronic outcome. In this study, we extended our analyses, by increasing the number of case-control samples to a total of 672 schizophrenics and 686 controls, and excluded potential sample stratification effects. We confirmed the significant allelic association between the repeat polymorphism and disease (P = 0.011), and as in the previous study, we observed an over-representation of longer alleles in schizophrenia. These results suggest a probable genetic effect for the GRIN2A promoter (GT)n variation on the predisposition to schizophrenia in Japanese cohorts.

Disrupted-in-Schizophrenia-1 (DISC1) is a gene in which a mutant truncation by a balanced t(1;11)(p42.1;q14.3) translocation is segregated with major psychiatric illness with a predominance of schizophrenic symptomatology in a large Scottish family. However, no functional polymorphisms have been detected that are associated with schizophrenia in general populations. As prior polymorphism searches in DISC1 have been focused on coding exons and flanking introns, the present study examined sequence variations in the 5' upstream region of DISC1. Screening of exon 1 through to approximately 1.0 kb upstream of exon 1 identified 6 polymorphisms, including 2 novel variants, -94C>A and -199(CG)(n). We tested these variants for associations with schizophrenia in the first set of a case (n = 198) and control (n = 198) panel, and found significant results with -274G>C (genotypic P = 0.01) and -215(TG)(n) (genotypic P = 0.039). However, we failed to replicate these associations in a second, larger independent patient (n = 532) and control (n = 519) sample. These results suggest that the genomic interval of DISC1 probably involved in transcriptional regulation does not display major genetic relevance in Japanese schizophrenia patients.

The deposition of tau inclusions is one of the neuropathological hallmarks in neurodegenerative disorders with dementia. We have reported that the N-terminal fragment of a human granin-like neuroendocrine peptide precursor (N-proSAAS) is accumulated in Pick bodies. However, it is unknown whether N-proSAAS is widely accumulated in tau inclusions in other tauopathies. Here, we performed an immunohistochemical examination using antibodies against both the N- and C-terminal sequence of proSAAS in the brains of patients with Alzheimer's disease and parkinsonism-dementia complex on Guam. The antibody against N-proSAAS immunostained neurofibrillary tangles and neuritic plaques in both diseases, whereas the antibody against the C-terminal sequence of proSAAS did not. The results of the present study suggest that N-proSAAS or proSAAS-like molecules were trapped within the tau fibrils and accumulated in tau inclusions.

Pharmacological evidence suggests the involvement of gamma-aminobutyric acid (GABA) perturbation in the etiology of mood disorders. A linkage study has detected chromosomal area 5q34, where GABA type A (GABA(A)) receptor subunit genes are mapped, as a susceptibility region for mood disorders, making these genes compelling candidates for such diseases. Our prior quantitative trait loci (QTL) analysis of mouse depression models identified a QTL on mouse chromosome 11, a genomic region whose human synteny includes 5q34. This further supports a contribution from GABA(A) receptors to a predisposition towards mood disorder. In the present study, we examined GABA(A) receptor alpha1 (GABRA1), alpha6 (GABRA6) and gamma2 (GABRG2) subunit genes on 5q34. Polymorphisms on GABRA1 and GABRA6 genes displayed significant associations with mood disorders in female patients. These data offer genetic support for a role of GABA(A) receptor genes in susceptibility to mood disorders.

The sequencing of the ascidian Ciona intestinalis genome was completed at the end of 2002. Effective targeted gene knockdown in this model chordate would greatly enhance understanding of how the genes affect the function of the neurons that underlie behaviour. We show here that antisense morpholinos (MOs) are effective and specific translational inhibitors in C. intestinalis larvae. The larvae developed from eggs injected with a Ci-opsin1 MO lost their photoresponse, which affected their swimming behaviour. Immunohistochemical analysis showed that the expression of Ci-opsin1, the visual pigments in the photoreceptor of the ocellus, had been lost in the larvae with the Ci-opsin1 MO. The inhibition of the photic behaviour of the knockdown larvae is solely due to the suppression of the synthesis of the visual pigments in the photoreceptors. These are the first results showing the knockdown of an ascidian gene and the elucidation of that gene's role in ascidian larval behaviour.

Hypoactivity of neuropeptide Y (NPY) is thought to be involved in the pathophysiology of schizophrenia, because post-mortem brain studies revealed a decrease of the NPY in schizophrenia, and antipsychotic treatments increase the NPY in animal brains and in cerebrospinal fluid of patients. We performed genetic analysis of the NPY gene in schizophrenia. Mutation screening of the gene detected nine single nucleotide polymorphisms, of which we typed a -485C>T variation from potential functional relevance. The -485T allele was overly represented in the disease group (P=0.0043). An in vitro promoter assay revealed that a C to T change at nt -485 significantly reduced transcriptional activity. These results suggest that the -485T allele in NPY may confer susceptibility to schizophrenia by decreasing the neuropeptide in brains.

Hypofunction of glutamatergic neurotransmission has been hypothesized to underlie the pathophysiology of bipolar affective disorder, as well as schizophrenia. We examined the role of the N-methyl-D-aspartate receptor 2A subunit (GRIN2A) gene on 16p13.3, a region thought to be linked to bipolar disorder, (1) because in a prior study we identified a functional and polymorphic (GT)n repeat in the 5' regulatory region of the gene, with longer alleles showing lower transcriptional activity and an over representation in schizophrenia, and (2) because of the suggestion of a genetic overlap between affective disorder and schizophrenia. Family-based association tests detected a nominally significant preferential transmission of longer alleles in a panel of 96 multiplex bipolar pedigrees. These results support the hypothesis that a hypoglutamatergic state is involved in the pathogenesis of bipolar affective disorder.

We have previously performed a genome scan in 22 multiplex pedigrees with bipolar disorder and detected a moderate linkage signal on distal portion of chromosome 14q22-32. One of the large pedigrees displayed a parametric lod score >3 at a marker on 14q23-32. Upon inspection of genes located in this region revealed AKT1, a kinase that activates a lithium-responsive cell-survival pathway. Because lithium is an effective mood stabilizer for bipolar disorder patients, AKT1 is an interesting candidate for further investigation. We screened the gene for possible mutations and detected 14 polymorphisms. Seven polymorphic sites were clustered in a small segment spanning exon 14 and downstream intron. Transmission of haplotypes constructed from this cluster showed a weak evidence of association between the AKT1 and bipolar disorder.

In the central nervous system (CNS), Thy-1 is expressed predominantly on neurons and serves as a specific marker for neurons. In the present study, we established a two-site enzyme-linked immunosorbent assay (ELISA) that detects trace amounts of Thy-1 protein. Recombinant Thy-1 protein expressed in Escherichia coli was purified and used as a standard. Of the regions of the nervous system examined, the highest Thy-1 concentration was found in the striatum followed by the hippocampus, neocortex, cerebellum, spinal cord, retina and optic nerve. We found that injection of a neurotoxin, N-methyl-D-aspartate, into the vitreous cavity reduced the Thy-1 level in the retina. Thy-1 ELISA will be useful for quantitative assessment of neurodegeneration in the CNS., (Copyright 2002 Elsevier Science Ireland Ltd.)

Several studies, including one from Japan, have observed an increase of Human Leukocyte Antigen (HLA)-A24 and A26 in schizophrenia, although others failed to observe the increase. No use of systematic diagnostic criteria and a not-adequately reliable typing technique might have affected the results in the previous studies. We investigated HLA-A specificities in Japanese patients with schizophrenia (DSM-IV), recruited from the same area as in the early Japanese study. A DNA-based technique (polymerase chain reaction-microtiter plate hybridization) was employed. No significant difference was observed in frequencies of any HLA-A specificities between patients and controls, including A24 and A26. No significant association was found between the HLA-A and birth-season in patients. Thus, no evidence was obtained for an association between HLA-A and schizophrenia from the Japanese population., (Copyright 2002 Elsevier Science Ireland Ltd.)

Intraventricular infusion of antiserum to nerve growth factor (ANGF), but not that to insulin, epidermal growth factor nor normal rabbit serum, resisted estrogen-induced behavioral defeminization in the female rat neonates. A significant number of the ANGF-treated rats showed lordosis as adults despite neonatal estrogen, but positive feedback of estrogen on serum luteinizing hormone was absent. Sexual phenotype in behavioral and gonadotropic functions may be under differential development regulation.