Increased Serum Levels of α-Synuclein in Patients With Major Depressive Disorder.

OBJECTIVE: Epidemiologic studies have demonstrated that depression is a risk factor for dementia. In particular, dementia with Lewy bodies (DLB) has been noted to be highly relevant to depression. It has been suggested that α-synuclein (α-syn), a major component of Lewy bodies, is related to the onset and progression of DLB. To investigate the relationship between depression and DLB, we compared serum α-syn levels of patients with depression to those of healthy subjects. METHODS: The subjects were 103 inpatients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), or DSM-5 major depressive disorder (MDD) and 132 healthy comparisons. Patients were recruited from Juntendo Koshigaya Hospital, Saitama, Japan, between June 2010 and November 2016. Serum α-syn levels were measured using an enzyme-linked immunosorbent assay kit. Serum α-syn levels were compared using a 2 (age group [<60 years versus ≥60 years]) × 2 (diagnosis [MDD versus comparison]) analysis of variance. RESULTS: There was no significant main effect of age (F = 1.167, df = 1, 231, p = 0.281). There was a significant main effect of diagnosis (F = 44.657, df = 1, 231, p <0.001), with higher α-syn levels in the MDD group versus the healthy comparison group, regardless of age. CONCLUSION: The present results suggest that depression may affect the metabolism of α-syn; there is a possibility that depression is not only a prodromal symptom of DLB but also a causal risk factor for DLB.

123I-MIBG myocardial scintigraphy for the diagnosis of DLB: a multicentre 3-year follow-up study.

BACKGROUND AND PURPOSE: We previously reported the usefulness of iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy for differentiation of dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) in a cross-sectional multicentre study. The aim of this study was, by using reassessed diagnosis after 3-year follow-up, to evaluate the diagnostic accuracy of 123I-MIBG scintigraphy in differentiation of probable DLB from probable AD. METHODS: We undertook 3-year follow-up of 133 patients with probable or possible DLB or probable AD who had undergone 123I-MIBG myocardial scintigraphy at baseline. An independent consensus panel made final diagnosis at 3-year follow-up. Based on the final diagnosis, we re-evaluated the diagnostic accuracy of 123I-MIBG scintigraphy performed at baseline. RESULTS: Sixty-five patients completed 3-year follow-up assessment. The final diagnoses were probable DLB (n=30), possible DLB (n=3) and probably AD (n=31), and depression (n=1). With a receiver operating characteristic curve analysis of heart-to-mediastinum (H/M) ratios for differentiating probable DLB from probable AD, the sensitivity/specificity were 0.77/0.94 for early images using 2.51 as the threshold of early H/M ratio, and 0.77/0.97 for delayed images using 2.20 as the threshold of delayed H/M ratio. Five of six patients who were diagnosed with possible DLB at baseline and with probable DLB at follow-up had low H/M ratio at baseline. CONCLUSIONS: Our follow-up study confirmed high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy at baseline and the clinical diagnosis of probable DLB at 3-year follow-up. Its diagnostic usefulness in early stage of DLB was suggested. TRIAL REGISTRATION NUMBER: UMIN00003419.

Disease state changes and safety of long-term donepezil hydrochloride administration in patients with Alzheimer's disease: Japan-Great Outcome of Long-term trial with Donepezil (J-GOLD).

BACKGROUND: A long-term, large-scale study of donepezil hydrochloride in patients with Alzheimer's disease (AD) was conducted. Previously, two interim reports were published during this study. We have now completed the study and herein present our analysis of the final results. METHODS: The subjects of this study included AD patients who received the drug for the first time (newly treated patients), as well as AD patients who were already receiving the drug at the start of the study (continuously treated patients). The observation period was 48 months. Changes in cognitive function and severity of dementia associated with the drug administration and its safety were assessed. RESULTS: Cognitive function decreased significantly after 24 months in newly treated patients and after 6 months in continuously treated patients, compared with baseline. The percentages of patients whose dementia severity improved or remained the same compared with baseline were 59.27% at 48 months in the newly treated patients and 57.09% at 48 months in the continuously treated patients. There were no major safety problems with the drug. CONCLUSIONS: We conducted a large-scale study of AD patients in Japan. Here, we present our analysis of the final results and describe current clinical practice with the drug, changes in cognitive function and dementia severity associated with long-term administration of the drug, and the drug's safety.

123I-FP-CIT SPECT findings and its clinical relevance in prodromal dementia with Lewy bodies.

PURPOSE: Evidence for the prodromal stage of dementia with Lewy bodies (DLB) is very limited. To address this issue, we investigate the 123I-FP-CIT SPECT measure of dopamine transporter binding finding and its clinical relevance. METHODS: We enrolled subjects into a prodromal DLB group (PRD-DLB) (n = 20) and clinical DLB group (CLIN-DLB) (n = 18) and compared these groups with an Alzheimer's disease control group (AD) (n = 10). PRD-DLB was defined as patients having the non-motor symptoms associated with Lewy body disease (LBD) [i.e. REM sleep behavior disorder (RBD), olfactory dysfunction, autonomic dysfunction, and depression] and showing characteristic diffuse occipital hypometabolism in 18F-FDG PET. CLIN-DLB was defined as patients fulfilling the established criteria of probable DLB. Striatal specific binding ratio (SBR) of 123I-FP-CIT SPECT was used for objective group comparisons. The correlations between SBR and cognitive function (MMSE), motor symptoms (UPDRS3), and duration of LBD-associated non-motor symptoms were compared between the two DLB groups. RESULTS: Mean SBR scores of both PRD-DLB and CLIN-DLB were significantly lower than those of AD. No correlation was found between SBR and MMSE scores. Both in the CLIN-DLB and total DLB groups, SBR scores were negatively correlated with UPDRS3 scores, whereas no correlation was found in PRD-DLB. Among the LBD-related non-motor symptoms, duration of olfactory dysfunction, and RBD demonstrated negative correlation with SBR scores in PRD-DLB. CONCLUSION: 123I-FP-CIT SPECT may play a role for detecting DLB among the subjects in prodromal stage. During this stage, long-term olfactory dysfunction and/or RBD may indicate more severe degeneration of the nigro-striatal dopaminergic pathway.

Genetic association between RAGE polymorphisms and Alzheimer's disease and Lewy body dementias in a Japanese cohort: a case-control study.

BACKGROUND/AIMS: Interaction of receptor for advanced glycation end products (RAGE) with amyloid-ß increases amplification of oxidative stress and plays pathological roles in Alzheimer's disease (AD). Oxidative stress leads to α-synuclein aggregation and is also a major contributing factor in the pathogenesis of Lewy body dementias (LBDs). Therefore, we aimed to investigate whether RAGE gene polymorphisms were associated with AD and LBDs. METHODS: Four single nucleotide polymorphisms (SNPs)-rs1800624, rs1800625, rs184003, and rs2070600-of the gene were analyzed using a case-control study design comprising 288 AD patients, 76 LBDs patients, and 105 age-matched controls. RESULTS: Linkage disequilibrium (LD) examination showed strong LD from rs1800624 to rs2070600 on the gene (1.1 kb) in our cases in Japan. Rs184003 was associated with an increased risk of AD. Although there were no statistical associations for the other three SNPs, haplotypic analyses detected genetic associations between AD and the RAGE gene. Although relatively few cases were studied, results from the SNPs showed that they did not modify the risk of developing LBDs in the Japanese population. CONCLUSION: Our findings suggested that polymorphisms in the RAGE gene are involved in genetic susceptibility to AD. Copyright © 2016 John Wiley & Sons, Ltd.

Simultaneous resting-state functional MRI and electroencephalography recordings of functional connectivity in patients with schizophrenia.

AIM: It remains unclear how functional connectivity (FC) may be related to specific cognitive domains in neuropsychiatric disorders. Here we used simultaneous resting-state functional magnetic resonance imaging (rsfMRI) and electroencephalography (EEG) recording in patients with schizophrenia, to evaluate FC within and outside the default mode network (DMN). METHODS: Our study population included 14 patients with schizophrenia and 15 healthy control participants. From all participants, we acquired rsfMRI data, and simultaneously recorded EEG data using an MR-compatible amplifier. We analyzed the rsfMRI-EEG data, and used the CONN toolbox to calculate the FC between regions of interest. We also performed between-group comparisons of standardized low-resolution electromagnetic tomography-based intracortical lagged coherence for each EEG frequency band. RESULTS: FC within the DMN, as measured by rsfMRI and EEG, did not significantly differ between groups. Analysis of rsfMRI data showed that FC between the right posterior inferior temporal gyrus and medial prefrontal cortex was stronger among patients with schizophrenia compared to control participants. CONCLUSION: Analysis of FC within the DMN using rsfMRI and EEG data revealed no significant differences between patients with schizophrenia and control participants. However, rsfMRI data revealed over-modulated FC between the medial prefrontal cortex and right posterior inferior temporal gyrus in patients with schizophrenia compared to control participants, suggesting that the patients had altered FC, with higher correlations across nodes within and outside of the DMN. Further studies using simultaneous rsfMRI and EEG are required to determine whether altered FC within the DMN is associated with schizophrenia.

Serum Levels of Albumin-ß-Amyloid Complex in Patients with Depression.

OBJECTIVE: Epidemiologic studies have demonstrated that suffering from depression may be a risk for Alzheimer disease (AD). As a possible biologic mechanism underlying the transition from depression to AD, it has been speculated that pathologic changes in ß-amyloid (Aß) metabolism are involved. To further understand the peripheral kinetics of amyloid in patients with depression, we investigated serum levels of free Aß and albumin-bound Aß. METHODS: Seventy inpatients with DSM-IV major depressive disorder (MDD) and 81 healthy individuals (the comparison group) were recruited between June 2012 and February 2014. Serum Aß40 and Aß42 levels, Aß40/Aß42 ratio, and serum levels of albumin-Aß complexes (SLAACs) were compared between the comparison group and patients in two age groups comprising younger (<60 years) and elderly (≥60 years) people. RESULTS: SLAAC was decreased in older patients with MDD but not in younger patients. The serum-free Aß40/Aß42 ratio was higher in patients with depression, even in younger patients. CONCLUSION: Our findings suggest that free Aß and the albumin-bound Aß reflect a different serum amyloid kinetics in depression. We speculate that serum-free Aß reflects changes in amyloid metabolism in patients suffering from depression and albumin-bound Aß reflects AD pathology and may be a potential predictor of the prodromal stage of AD.

Mortality risk in current and new antipsychotic Alzheimer's disease users: Large scale Japanese study.

INTRODUCTION: We studied the mortality risk of long term and new antipsychotic drug use in Alzheimer's disease (AD) patients in Japan to determine improved treatment protocols. METHODS: This 24-week prospective cohort study included 10,079 Japanese AD patients (female, 69%; average age, 81 years) under routine clinical care in 357 medical sites. The antipsychotic medication history was varied (63.7% were long-term users). Mortality rates and odds ratio were analyzed (initial 10 weeks and from 11-24 weeks). RESULTS: The antipsychotic exposed group with shorter treatment periods had a higher mortality risk compared to controls. The newly prescribed users (antipsychotic treatment started during the follow-up) showed increased mortality (9.4% during the 11-24 week period). CONCLUSIONS: New use of antipsychotic drugs represents a distinct risk for mortality; those on long-term antipsychotic therapy seem to be at less risk. The warning issued 10 years earlier on antipsychotics use for AD patients should be reviewed.

Serum insulin-like growth factor-I and amyloid beta protein in Alzheimer's disease: relationship with cognitive function.

AIMS: Previous studies have suggested that insulin-like growth factor-I (IGF-I) deficiency may lead to cognitive deficits in neurodegenerative diseases such as Alzheimer's disease. The present study aimed to investigate the possible relationship between cognitive function and concentration of IGF-I or amyloid beta protein (Aß) in serum in Alzheimer's patients. METHODS: A total of 81 Japanese patients were enrolled in this study. Concentrations of IGF-I, Aß42, and Aß40 in serum were measured. Two neuropsychological tests, Mini-Mental State Examination and Hasegawa's Dementia Scale-Revised (HDS-R), were also performed. Linear correlations among the age, serum IGF-I, serum Aß42 or Aß40, Aß42/Aß40 ratio, Mini-Mental State Examination or HDS-R total score, and the scores for six HDS-R subscales were analyzed by regression analysis. RESULTS: IGF-I showed a significant negative correlation with age (ß = -0.357, P = 0.002) and a positive correlation with Aß42/Aß40 ratio (ß = 0.318, P = 0.007). Serum IGF-I and both the Mini-Mental State Examination and the HDS-R total score also correlated (ß = 0.505, ß = 0.524, P < 0.01). Among the HDS-R subscales, 'Recall' (ρ = 0.379, P < 0.01), 'Verbal fluency' (ρ = 0.360, P < 0.01), and 'Attention and calculation' (ρ = 0.389, P < 0.01) showed significant positive correlations with serum IGF-I. CONCLUSION: The results, specifically that lower serum IGF-I was associated with cognitive impairment, suggest that metabolism of IGF-I may be involved in the pathogenesis of cognitive deficits in Alzheimer's disease.

Disease state changes and safety of long-term donepezil hydrochloride administration in patients with Alzheimer's disease: interim results from the long-term, large-scale J-GOLD study in Japan.

BACKGROUND: There have been very few long-term studies involving a large study population; existing studies usually have no more than a few hundred patients with Alzheimer's disease. For these reasons, there are no detailed investigations regarding changes in activities of daily living evaluated by the Functional Assessment Staging Test (FAST). METHODS: A long-term, large-scale observational study of donepezil hydrochloride (Aricept(®); Eisai Co., Ltd, Tokyo, Japan) is currently in progress. Its objective is to investigate disease state changes associated with the long-term administration of this drug and its safety in patients with Alzheimer's disease. In this report, data collected over a maximum of 24 months were compiled. Efficacy was assessed using FAST and a cognitive function test (Mini-Mental State Examination or the Hasegawa's Dementia Scale-Revised). RESULTS: The percentages of patients whose FAST stage improved or remained the same compared to at the start of donepezil hydrochloride administration (baseline) were 91.1% at 6 months, 83.0% at 12 months, 79.5% at 18 months, and 74.8% at 24 months. Multivariate logistic regression analysis was conducted to investigate factors that affect the improvement and maintenance or exacerbation of FAST at 24 months. 'Independence level in the daily life of elderly with dementia' and 'duration of illness' were identified as variables that affected the improvement and maintenance or exacerbation of FAST. Cognitive function improved significantly at 12 weeks and at 6 months compared to baseline, maintained baseline levels at 12 months and at 18 months, and decreased significantly at 24 months compared to baseline. CONCLUSIONS: This is the largest prospective study involving Alzheimer's disease patients in Japan, and we believe it is an important study that shows the reality of daily clinical practice.

Association of copy number polymorphisms at the promoter and translated region of COMT with Japanese patients with schizophrenia.

Chromosome 22q11.2 deletion syndrome and genetic variations including single-nucleotide polymorphism (SNP) and copy number variation (CNV) in catechol-O-methyltransferase (COMT) situated at 22q11.2 remains controversial. Here, the genetic relationship between COMT and Japanese patients with schizophrenia was investigated by examining whether the SNPs correlated with schizophrenia based on a common disease-common variant hypothesis. Additionally, 22q11.2DS were screened based on a common disease-rare variant hypothesis; low-frequency CNVs situated at two COMT promoters and exons were investigated based on the low-frequency variants with an intermediate effect; and positive findings from the first stage were reconfirmed using a second-stage replication study including a larger sample size. Eight SNPs and 10 CNVs were investigated using Taqman SNP and CNV quantitative real-time polymerase chain reaction method. For the first-stage analysis, 513 unrelated Japanese patients with schizophrenia and 705 healthy controls were examined. For the second-stage replication study, positive findings from the first stage were further investigated using a larger sample size, namely 1,854 patients with schizophrenia and 2,137 controls. The first-stage analysis showed significant associations among schizophrenia, intronic SNP rs165774, CNV6 situated at promoter 1, CNV8 at exon 6, and CNV9 at exon 7. The second-stage study showed that intronic SNP rs165774 (χ(2) = 8.327, P = 0.0039), CNV6 (χ(2) = 19.66, P = 0.00005), and CNV8 (χ(2) = 16.57, P = 0.00025) were significantly associated with schizophrenia. Large and rare CNVs as well as low-frequency CNVs and relatively small CNVs, namely <30 kb in COMT, may be genetic risk factors for schizophrenia.

[A real-world survey on antipsychotic treatment for BPSD].

Despite US Food and Drug Administration black box warning, antipsychotics are frequently used for behavioral and psychological symptoms of dementia (BPSD) of Alzheimer's disease (AD). A 24-weeks prospective cohort study of 10,079 Japanese AD patients in. 357 medical sites was done. The mortality rates in the whole exposed group did not differ from those in the non-user control group. However, further analysis disclosed that the exposed group with shorter treatment periods had higher mortality risk. The results confirmed the mortality associated with antipsychotics suggesting that new use of antipsychotics should be avoided. Patients having been maintained on the drugs for long periods may be at less risk.

[Suggestions Obtained from the J-CATIA Study (Japan Consortium for Antipsychotics Treatment in Alzheimer's Disease)].

The mortality risk of long-term and new antipsychotic drug use in Alzheimer's disease (AD) patients in Japan was studied to determine improved treatment protocols. One of the main findings was that newly prescribed users showed increased mortality. Therefore, the new use of antipsychotic drugs represents a distinct mortality risk, while those on long-term anti- psychotic therapy are suggested to be relatively safe.

Clinical profiles of dementia with Lewy bodies with and without Alzheimer's disease-like hypometabolism.

OBJECTIVES: It is well known that Alzheimer's disease (AD)-type pathology is commonly present in dementia with Lewy bodies (DLB) brains and that the degree of AD-type pathology has an influence on the clinical characteristics of DLB. Although significant hypometabolism in the temporoparietal/precuneus on [(18)F]fluoro-d-glucose ((18)F-FDG) positron emission tomography (PET) scans is considered to support a diagnosis of AD, some DLB patients also exhibit this metabolic pattern. The clinical significance of the metabolic pattern on DLB remains unknown. METHODS: Twenty-three DLB patients, 10 AD patients, and 11 controls underwent (18)F-FDG PET scans. According to the degree of hypometabolism in the parietal/precuneus regions, representing the AD-like metabolic pattern, 12 patients were placed in the DLB-AD(+) group and 11 patients were placed in the DLB-AD(-) group. The demographics and clinical variables were compared among the four groups. RESULTS: In addition to the parietal/precuneus regions, the DLB-AD(+) group exhibited significantly greater posterior cingulate hypometabolism than the DLB-AD(-) group, although occipital metabolism did not differ. The prevalence of visual hallucinations and extracampine hallucinations, and the Bender-Gestalt test score were significantly higher in the DLB-AD(+) group than the DLB-AD(-) group, although there were no differences in the demographics and other examined clinical variables between the two DLB groups. These clinical differences were absent in the DLB-AD(-) group, AD group, and controls. CONCLUSIONS: Parietal/precuneus hypometabolism may be associated with clinical characteristics in DLB patients. Further multiple imaging modalities that are sensitive to AD-type pathology are needed to reveal the neurobiological basis of the AD-like metabolic pattern.

Association between the catechol-O-methyltransferase polymorphism Val158Met and Alzheimer's disease in a Japanese population.

OBJECTIVE: Catechol-O-methyltransferase (COMT) plays an important role in dopamine degradation, which is associated with the pathophysiology of Alzheimer's disease (AD) and alcoholism. A functional COMT polymorphism, Val158Met (rs4680 G > A), affects the onset of AD and is associated with alcohol dependence through dopamine receptor sensitivity in the prefrontal cortex. METHODS: The aim of this case-control study (398 cases and 149 controls) was to investigate whether Val158Met polymorphism influences the onset of AD stratified according to alcohol consumption and apolipoprotein E (APOE) status. We also used single photon-emission computed tomography (SPECT) to analyse 26 patients with AD with the polymorphism. RESULTS: As a function of APOE status, the genotypic frequencies of rs4680 in patients with AD did not differ from those in controls. We detected a significant association between high alcohol consumption in patients with AD (HAC-AD group) and the polymorphism in genotypic and allelic frequencies. Logistic regression analyses demonstrated that the presence of the APOE genotype with rs4680 increased the risk for HAC-AD synergistically. Hyperperfusion in the right sub-lobar insula of patients with the G/G genotype was found compared with that of patients with the G/A genotype. SPECT studies showed a relationship between the polymorphism and compensatory reactions for dysfunctions of dopaminergic neurotransmission in AD pathophysiology. CONCLUSION: Although genetic association between the polymorphism and the onset of AD in a Japanese population were not observed, the polymorphism affected the risk for HAC-AD.

Serum brain-derived neurotrophic factor levels and personality traits in patients with major depression.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family of growth factors. Previous studies have demonstrated lower serum BDNF levels in patients with major depressive disorder (MDD) and reported an association between BDNF levels and depression-related personality traits in healthy subjects. The aim of the present study was to explore for a possible association between peripheral BDNF levels and personality traits in patients with MDD. METHODS: In this cross-sectional study, a total of 123 inpatients with MDD (Diagnostic and Statistical Manual for Mental Disorders, 4th edition) at the Juntendo University Koshigaya Hospital were recruited. Serum levels of BDNF were measured. Personality traits were assessed using the 125-item short version of the Temperament and Character Inventory (TCI). RESULTS: Multiple regression analysis adjusted for age, sex, body mass index, dose of antidepressant, and depression severity showed that TCI Self-Directedness (SD) scores were negatively associated with serum BDNF levels (ß = -0.23, p = 0.026). CONCLUSIONS: MDD patients who have low SD did not show the reduction in serum BDNF levels that is normally associated with depressive state. Our findings suggest that depression-related biological changes may not occur in these individuals.

An autopsied case of corticobasal degeneration showing severe cerebral atrophy over a protracted disease course of 16 years.

The patient was a 72-year-old Japanese woman. At the age of 57, she started having difficulty performing daily work and developed agraphia. She also exhibited restlessness and loss of interest, and began to speak less. Thereafter, stereotypical behavior, gait disturbance and dysphagia were noted. CT scan demonstrated left-dominant frontal and temporal lobe atrophy. She died at the age of 72, about 16 years after the onset of symptoms. Neuropathologically, the brain weighed 867 g, and showed remarkable cerebral atrophy with degeneration of the white matter, predominantly in the left dorsal frontal lobe and anterior temporal lobe. Microscopically, severe neuronal loss and gliosis with rarefaction were found in the cerebral cortex, and severe destruction of myelin and axons was observed in the cerebral white matter. Moderate neuronal loss with gliosis was also found in the pallidum and substantia nigra. Gallyas-Braak staining and tau immunostaining revealed pretangle neurons, NFTs, ballooned neurons and astrocytic plaques in the cerebral cortex, subcortical nuclei and brainstem, and argyrophilic threads and coiled bodies in the subcortical white matter. Tau isoform-specific immunostaining revealed that most tau-immunoreactive structures were positive for 4-repeat (4R) tau, but some of the NFTs were positive for 3-repeat (3R) tau in the cerebral neocortex. Immunoblotting demonstrated an accumulation of 4R tau in the cerebral cortex and subcortical white matter. The patient was pathologically diagnosed as having corticobasal degeneration. Her long survival course likely accounts for the severe white matter degeneration and accumulation of 3R tau in NFTs.

Pilot intervention study of a low-salt diet with monomagnesium di-L-glutamate as an umami seasoning in psychiatric inpatients.

BACKGROUND: Schizophrenia patients have an elevated prevalence of stroke and cardiovascular risk factors, such as elevated body mass index, hypertension, and hyperlipidaemia. This pilot study investigated the influence of a low-sodium diet using umami seasoning on food intake and clinical parameters in schizophrenia patients. METHODS: A single-blind crossover intervention study was conducted in 15 clinical schizophrenia patients given a low-sodium diet with or without umami seasoning, monomagnesium di-L-glutamate, for 2 weeks. After the initial 2-week intervention, there was a 2-week washout period, and then the interventions were switched. Daily body weight, body mass index, abdominal circumference, blood pressure, and nutrient intake for each subject were determined. RESULTS: The results showed that subjects given monomagnesium di-L-glutamate had an approximately 25.9% reduction in dietary sodium. Furthermore, daily energy intake did not decrease, and no significant changes in body weight, body mass index, abdominal circumference, blood pressure, and nutrient intake were observed. CONCLUSIONS: The use of umami seasonings, such as monomagnesium di-L-glutamate, might be an effective long-term strategy for psychiatric patients requiring restricted sodium intake.

Associations of common copy number variants in glutathione S-transferase mu 1 and D-dopachrome tautomerase-like protein genes with risk of schizophrenia in a Japanese population.

Oxidative-stress, genetic regions of interest (1p13 and 22q11), and common copy number variations (CNVs) may play roles in the pathophysiology of schizophrenia. In the present study, we confirmed associations between schizophrenia and the common CNVs in the glutathione (GSH)-related genes GSTT1, DDTL, and GSTM1 using quantitative real-time polymerase chain reaction analyses of 620 patients with schizophrenia and in 622 controls. No significant differences in GSTT1 copy number distributions were found between patient groups. However, frequencies of characterized CNVs and assumed gain alleles of DDTL and GSTM1 were significantly higher in patients with schizophrenia. In agreement with a previous report, the present data indicate that gains in the CNV alleles DDTL and GSTM1 are genetic risk factors in Japanese patients with schizophrenia, and suggest involvement of micro-inflammation and oxidative stress in the pathophysiology of schizophrenia.

Polymorphisms in the aldehyde dehydrogenase 2 and dopamine ß hydroxylase genes are not associated with Alzheimer's disease.

Since ethanol and its metabolite, acetaldehyde, are directly neurotoxic, alcohol intake could affect the development of Alzheimer's disease (AD). Mitochondrial aldehyde dehydrogenase 2 (ALDH2) metabolizes acetaldehyde into acetate and also protects against oxidative stress, playing an important role in the development of AD. The activity of dopamine ß hydroxylase (DBH) is reduced in the hippocampus and neocortex in the AD brain. DBH is also involved in the pathophysiology of alcoholism. The aim of this study was to investigate whether polymorphisms of both ALDH2 and DBH genes were associated with AD. ALDH2*2 and two functional single nucleotide polymorphisms (SNPs) of the DBH gene were analyzed using a case-control study design. Our case-control data set consisted of 201 AD patients and 130 age-matched controls. We also analyzed stratifying by alcohol consumption and apolipoprotein E (APOE) genotypes. There were no associations between the SNPs studied here and the onset of AD. No synergetic associations were found among the SNPs, APOE and the risk for AD. Although high alcohol consumption AD (HAC-AD) patients were analyzed in detail, the current three SNPs were not related with HAC-AD. ALDH2*2 and functional SNPs of the DBH gene did not modify the risk for AD. Since our data set was constructed only with AD in a Japanese population, further detailed genetic analyses with other ethnic groups would be needed.