Polyunsaturated fatty acid deficiency during neurodevelopment in mice models the prodromal state of schizophrenia through epigenetic changes in nuclear receptor genes.

The risk of schizophrenia is increased in offspring whose mothers experience malnutrition during pregnancy. Polyunsaturated fatty acids (PUFAs) are dietary components that are crucial for the structural and functional integrity of neural cells, and PUFA deficiency has been shown to be a risk factor for schizophrenia. Here, we show that gestational and early postnatal dietary deprivation of two PUFAs-arachidonic acid (AA) and docosahexaenoic acid (DHA)-elicited schizophrenia-like phenotypes in mouse offspring at adulthood. In the PUFA-deprived mouse group, we observed lower motivation and higher sensitivity to a hallucinogenic drug resembling the prodromal symptoms in schizophrenia. Furthermore, a working-memory task-evoked hyper-neuronal activity in the medial prefrontal cortex was also observed, along with the downregulation of genes in the prefrontal cortex involved in oligodendrocyte integrity and the gamma-aminobutyric acid (GABA)-ergic system. Regulation of these genes was mediated by the nuclear receptor genes Rxr and Ppar, whose promoters were hyper-methylated by the deprivation of dietary AA and DHA. In addition, the RXR agonist bexarotene upregulated oligodendrocyte- and GABA-related gene expression and suppressed the sensitivity of mice to the hallucinogenic drug. Notably, the expression of these nuclear receptor genes were also downregulated in hair-follicle cells from schizophrenia patients. These results suggest that PUFA deficiency during the early neurodevelopmental period in mice could model the prodromal state of schizophrenia through changes in the epigenetic regulation of nuclear receptor genes.

A snapshot of plasma metabolites in first-episode schizophrenia: a capillary electrophoresis time-of-flight mass spectrometry study.

Few biomarkers have been known that can easily measure clinical conditions in mental illnesses such as schizophrenia. Capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) is a new method that can measure ionized and low-molecular-weight metabolites. To explore global metabolomic alterations that characterize the onset of schizophrenia and identify biomarkers, we profiled the relative and absolute concentrations of the plasma metabolites from 30 patients with first-episode schizophrenia (FESZ, four drug-naïve samples), 38 healthy controls and 15 individuals with autism spectrum disorders using CE-TOFMS. Five metabolites had robust changes (increased creatine and decreased betaine, nonanoic acid, benzoic acid and perillic acid) in two independent sample sets. Altered levels of these metabolites are consistent with well-known hypotheses regarding abnormalities of the homocysteine metabolism, creatine kinase-emia and oxidative stress. Although it should be considered that most patients with FESZ received medication, these metabolites are candidate biomarkers to improve the determination of diagnosis, severity and clinical stages, especially for FESZ.

Measuring RNA editing of serotonin 2C receptor.

Pre-mRNA of serotonin 2C receptor (HTR2C, 5-hydroxytryptamine (serotonin) receptor 2C) undergoes A-to-I type RNA editing, which is a post-transcriptional event leading to the change of genomically encoded information. RNA editing generates various HTR2C isoforms, each of which has distinctive receptor activity. Postmortem, animal, and pharmacological studies have suggested that the altered RNA editing of HTR2C is involved in the pathophysiology of mental disorders, although results remain inconsistent. Here we review the techniques used for estimation of RNA editing of HTR2C. Among the techniques reported so far, a high-throughput sequencing-based method would be the most powerful method of choice for the large-scale experiments. Several different methods that were previously developed, such as pyrosequencing and capillary electrophoresis, should be suitable for validation as well as for rapid screening or exploratory purposes.

Hypermethylation of serotonin transporter gene in bipolar disorder detected by epigenome analysis of discordant monozygotic twins.

Bipolar disorder (BD) is a severe mental disorder characterized by recurrent episodes of mania and depression. Serotonin transporter (HTT) is a target of antidepressants and is one of the strongest candidate molecules of mood disorder, however, genetic study showed equivocal results. Here, we performed promoter-wide DNA methylation analysis of lymphoblastoid cell lines (LCLs) derived from two pairs of monozygotic twins discordant for BD. To rule out the possible discordance of copy number variation (CNV) between twins, we performed CNV analysis and found the copy number profiles were nearly identical between the twin pairs except for immunoglobulin-related regions. Among the three genes we obtained as candidate regions showing distinct difference of DNA methylation between one of the two pairs, hypermethylation of SLC6A4, encoding HTT, in the bipolar twin was only confirmed by bisulfite sequencing. Then, promoter hypermethylation of SLC6A4 in LCLs of BD patients was confirmed in a case-control analysis. DNA methylation of SLC6A4 was significantly correlated with its mRNA expression level in individuals with the S/S genotype of HTTLPR, and mRNA expression level was lower in BD patients carrying the S/S genotype. Finally, DNA methylation of the same site was also higher in the postmortem brains of BD patients. This is the first study to report the role of epigenetic modification of SLC6A4 in BD using an unbiased approach, which provides an insight for its pathophysiology.

Aberrant DNA methylation associated with bipolar disorder identified from discordant monozygotic twins.

To search DNA methylation difference between monozygotic twins discordant for bipolar disorder, we applied a comprehensive genome scan method, methylation-sensitive representational difference analysis (MS-RDA) to lymphoblastoid cells derived from the twins. MS-RDA isolated 10 DNA fragments derived from 5' region of known genes/ESTs. Among these 10 regions, four regions showed DNA methylation differences between bipolar twin and control co-twin confirmed by bisulfite sequencing. We performed a case-control study of DNA methylation status of these four regions by pyrosequencing. Two regions, upstream regions of spermine synthase (SMS) and peptidylprolyl isomerase E-like (PPIEL) (CN265253), showed aberrant DNA methylation status in bipolar disorder. SMS, a gene on X chromosome, showed significantly higher DNA methylation level in female patients with bipolar disorder compared with control females. However, there was no difference of mRNA expression. In PPIEL, DNA methylation level was significantly lower in patients with bipolar II disorder than in controls. The expression level of PPIEL was significantly higher in bipolar II disorder than in controls. We found strong inverse correlation between gene expression and DNA methylation levels of PPIEL. These results suggest that altered DNA methylation statuses of PPIEL might have some significance in pathophysiology of bipolar disorder..

Molecular characterization of bipolar disorder by comparing gene expression profiles of postmortem brains of major mental disorders.

We performed the oligonucleotide microarray analysis in bipolar disorder, major depression, schizophrenia, and control subjects using postmortem prefrontal cortices provided by the Stanley Foundation Brain Collection. By comparing the gene expression profiles of similar but distinctive mental disorders, we explored the uniqueness of bipolar disorder and its similarity to other mental disorders at the molecular level. Notably, most of the altered gene expressions in each disease were not shared by one another, suggesting the molecular distinctiveness of these mental disorders. We found a tendency of downregulation of the genes encoding receptor, channels or transporters, and upregulation of the genes encoding stress response proteins or molecular chaperons in bipolar disorder. Altered expressions in bipolar disorder shared by other mental disorders mainly consisted of upregulation of the genes encoding proteins for transcription or translation. The genes identified in this study would be useful for the understanding of the pathophysiology of bipolar disorder, as well as the common pathophysiological background in major mental disorders at the molecular level. In addition, we found the altered expression of LIM and HSPF1 both in the brains and lymphoblastoid cells in bipolar disorder. These genes may have pathophysiological importance and would be novel candidate genes for bipolar disorder.

High- and moderately high-methionine uptake demonstrated by PET in a patient with a subacute cerebral infarction.

In patients with cerebral tumors, high accumulations of L-methyl-11C-methionine (11C-Met) have been reported in some cases of cerebral ischemic disease, but no high accumulations of 11C-Met in areas where only transient arterial occlusions are most likely to occur have been reported. Herein we present a case of a high accumulation of 11C-Met in an area of frontal interhemispheric cerebral infarction and a moderately high accumulation with an unclear margin in a distant frontal convexity area. A craniotomy revealed a subacute stage of cerebral infarction in the interhemispheric lesion, and an ischemic change in the distant convexity area. Sixteen months after onset, CT scans demonstrated an infarction area in the interhemispheric lesion only, and no atrophic changes were observed in the distant convexity area indicating that no serious tissue damage had occurred.

Human visual motion areas determined individually by magnetoencephalography and 3D magnetic resonance imaging.

We used magnetoencephalography to study inter-individual locational difference in the extrastriate region which responds to visual motion. Magnetic responses to visual motion onset from the right temporo-occipital area were recorded from 12 subjects. All the subjects had clear responses to apparent or random dot coherent motion. The origins of these responses was investigated by use of the single equivalent current dipole model. The nearest scalp to the origin also was identified for each subject, which may be useful in transcranial stimulation studies. Although the magnetic responses of all the subjects should have the same functional properties; be related to neural activities synchronized exclusively to the onset of motion, the estimated origins varied greatly among the subjects. The location of origin could be classified as one of three types: temporo-occipital, occipital, or parietal, according to the sulcal anatomy investigated in the individual's three-dimensional magnetic resonance image. Temporo-occipital types were found for seven subjects, and anatomically the regions were around human MT/V5. Two subjects had the occipital type, with regions posterior to the anatomical MT/V5 and corresponding to V3A anatomically. The other three subjects had origins classified as the parietal type dorso-rostral to the anatomical MT/V5, with regions around the posterior end of the superior temporal sulcus. Although all these cortical regions appear to be related to the neural process of visual motion, whether they correspond functionally to the same names or migrated MT/V5 must now be determined.

Protein binding of a DRPLA family through arginine-glutamic acid dipeptide repeats is enhanced by extended polyglutamine.

Dentatorubral-pallidoluysian atrophy (DRPLA) is one of the hereditary neurodegenerative disorders caused by expansion of CAG/glutamine repeats. To investigate the normal function of the DRPLA gene and the pathogenic mechanism of neuron death in specific areas of the brain, we isolated and analyzed a gene that shares a notable motif with DRPLA, arginine-glutamic acid (RE) dipeptide repeats. The gene isolated, designated RERE, has an open reading frame of 1566 amino acids, of which the C-terminal portion has 67% homology to DRPLA, whereas the N-terminal portion is distinctive. RERE also contains arginine-aspartic acid (RD) dipeptide repeats and putative nuclear localization signal sequences, but no polyglutamine tracts. RERE is expressed at a low level in most tissues examined. Immunoprecipitation and in vitro binding assays demonstrate that the DRPLA and RERE proteins bind each other, for which one of the RE repeats has a primary role, and extended polyglutamine enhances the binding. With engineered constructs fused with a tag, the RERE protein localized predominantly in the nucleus. Moreover, when RERE is overexpressed, the distribution of endogenous DRPLA protein alters from the diffused to the speckled pattern in the nucleus so as to co-localize with RERE. More RERE protein is recruited into nuclear aggregates of the DRPLA protein with extended polyglutamine than into those of pure polyglutamine. These results reveal a function for the DRPLA protein in the nucleus and the RE repeat in the protein-protein interaction.

Neural activation of the brain with hemodynamic insufficiency.

Little is known about how ischemia affects hemodynamic responses to neural activation in the brain. We compare the effects of a motor activation task and a cerebral vasodilating agent, acetazolamide (ACZ), on regional cerebral blood flow (rCBF) in primary sensorimotor cortex (PSM) in six patients with major cerebral artery steno-occlusive lesions without paresis of the upper extremities. Quantitative rCBF was measured in all patients using H2(15)O autoradiographic method and positron emission tomography. The CBF was determined at rest, during a bimanual motor activation task, and 10 minutes after ACZ administration. With bimanual motor activation, rCBF increased significantly in both PSM compared with at rest (P < 0.01 on lesion side, and P < 0.02 on contralateral side). However, rCBF did not increase after ACZ injection in the PSM on the lesion side, whereas rCBF increased significantly in the contralateral PSM after ACZ injection compared with the level at rest. This result suggests that despite a decreased hemodynamic reserve, there is a nearly normal flow response to neural activation, indicating that the mechanism of vasodilation responsible for perfusion change is different for acetazolamide and neural activation. The relations among neural activation, hemodynamic status, and cerebral metabolism in the ischemic stroke patients are discussed.

[Peripheral arteriopathy in type 2 diabetes mellitus]. / Arteriopatía periférica en la diabetes mellitus tipo 2.

OBJECTIVES: To find the prevalence of peripheral arteriopathy (PA) in type 2 diabetics registered at a Health Centre, to detect their main risk factors and examine the usefulness of the portable Doppler in Primary Care consultations. DESIGN: A crossover descriptive study. SETTING: Urban Health Centre. PATIENTS: All the type 2 diabetics registered. MEASUREMENTS AND RESULTS: Anamnesis, physical examination, analysis and base ECG were performed. A portable Doppler determined systolic blood pressure in the lower extremities (foot and posterior tibial arteries) and brachial arteries in order to calculate the ankle/arm index (AAI). PA well recorded in the clinical history and AAI < or = 0.90 were considered criteria of PA. Diabetics with AAI > or = 1.25 were analysed separately. 289 patients with an average age of 65.3 (+/- 10.8 SD) were studied. 45.7% were men and 67% had Diabetes Mellitus for less than 10 years. 37.4% followed a dietary treatment and 21.1% were treated with insulin. Multivariate analysis showed that risk factors were: tobacco dependency, age, Hypertension and the type of treatment for the DM. CONCLUSIONS: The prevalence of PA found (21.4%) was very much higher than what had been previously diagnosed (6.9%). Identified risk factors were tobacco dependency, age, Hypertension and the type of DM treatment. A portable Doppler is easy to handle and allows peripheral arteriopathy to be diagnosed at an early stage.

Embolism in the superior cerebellar artery following coil embolization of basilar tip aneurysms: anatomy and hemodynamics.

SUMMARY: We aimed to identify anatomic factors favoring intra-aneurysmal clot embolization complicating coil embolization of basilar tip aneurysms. Thirty basilar tip aneurysm cases were classified angiographically into three types according to branching pattern of the superior cerebellar artery (SCA) and coil embolization complications were analyzed. The SCA may arise from the basilar artery (BA) just proximal to the origin of the posterior cerebral artery (PCA), initially coursing at an angle (more than 60 degrees ) relative to the BA, (type A). Alternatively the SCA may originate directly from the PCA at a sharp angle less than 30 degrees relative to the BA (type C). Type B includes patterns intermediate between types A and C. Behavior of particles chosen to simulate intra-aneurysmal clots was also observed in a plastic tube model with pulsatile water flow simulating configurations A and C. Type C branching was seen in 35% (21/60) of SCA, being dominant on the left side and associated with large aneurysms and broad necks. All 3 of 24 coil embolization patients with ischemic complications in the SCA territory had large aneurysms and type C SCA branching, 2 aneurysms having broad necks. in the plastic model embolized "clots" more frequently lodged in type C than in type A SCA. "Clots" close to the orifice migrated more easily than those in the dome of the plastic aneurysm. Large basilar tip aneurysms with broad necks carry a risk of intra-aneurysmal clot migration into the SCA, during and after the embolization, especially in type C configurations, because pulsatile blood flow in the basilar artery may disperse clots between the coils and carry them into the sharply angulated SCA. Avoiding this complication requires meticulous coil packing to interrupt inflow into the aneurysm as well as appropriate anti-coagulation therapy.

Determining the Optimal Fluoroscopic View during Aneurysmal Embolization with Rotation DSA.

SUMMARY: To prevent coil protrusion into the parent artery, the fluoroscopic view during coil packing is quite important. However it is not always easy to find out the optimal fluoroscopic view. We applied a rotation DSA to predict the optimal fluoroscopic view for the endovascular treatment of 4 cases with a cerebral aneurysm. Since the trajectory of the C-arm is restricted within 60 degrees only around the patient's head and the number of DSA shots are limited rather than conventional DSA, we employed three dimensional CT angiography (3D-CT angiography) to focus the range of C-arm rotation. Rotation DSA proved quite useful to determine the optimal fluoroscopic view, when combined with preestimation by 3D-CT angiography.

3D CT Angiography as a Pre-embolization Study for Embolization of Cerebral Aneurysms.

SUMMARY: An image guide for aneurysm embolization based on three dimensional CT angiography is reported. Multiplanner reformation (MPR) can measure the neck and dome of the aneurysm accurately enough to select the first coils for aneurysms. For neck evaluation, cut model and virtual endoscope are helpful because we can observe the neck from inside of dome or parent artery. Proximal arteries are visualized by 3D images and MPR if needed. Using laser lithography, we can get a real model of aneurysm and parent artery through which we can insert microcatheters and coils. 3D CTA is a dependable modality for embolization of cerebral aneurysms.

Dentatorubral and pallidoluysian atrophy expansion of an unstable CAG trinucleotide on chromosome 12p.

Dentatorubral and pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder characterized by combined systemic degeneration of the dentatofugal and pallidofugal pathways. We investigated a candidate gene and found that DRPLA patients had an expanded CAG trinucleotide repeat in a gene on the short arm of chromosome 12. The repeat size varied from 7-23 in normal individuals. In patients one allele was expanded to between 49-75 repeats or occasionally even more. Expansion was usually associated with paternal transmission and only occasionally with maternal transmission. Repeat size showed a close correlation with age of onset of symptoms and disease severity. We conclude that DRPLA is the seventh genetic disorder known to be associated with expansion of an unstable trinucleotide repeat.