Kaori Adachi

Anxiety traits associated with a polymorphism in the serotonin transporter gene regulatory region in the Japanese.

AbstractWe determined polymorphism in the serotonin (5-HT) transporter gene-linked polymorphic region (5-HTTLPR) in 501 healthy Japanese, individuals, using the polymerase chain reaction of Lesch et al., with minor modifications. The distribution of allele frequencies was determined and found to differ from that in Caucasians. We also investigated the relationship of polymorphism in 5-HTTLPR to anxiety traits, by having 189 of the 501 subjects complete a self-rating questionnaire for anxiety and depression. Subjects with the short/short (s/s) genotype had significantly higher anxiety scores than those with the long/long (l/l) or l/s genotype. It is suggested that populations with the s/s genotype of 5-HTTLPR have stronger anxiety-related personality traits than those with the l allele.

Chemical chaperone therapy: chaperone effect on mutant enzyme and cellular pathophysiology in β-galactosidase deficiency.

β‐Galactosidase deficiency is a group of lysosomal lipid storage disorders with an autosomal recessive trait. It causes two clinically different diseases, GM1‐gangliosidosis and Morquio B disease. It is caused by heterogeneous mutations in the GLB1 gene coding for the lysosomal acid β‐galactosidase. We have previously reported the chaperone effect of N‐octyl‐4‐epi‐β‐valienamine (NOEV) on mutant β‐galactosidase proteins. In this study, we performed genotype analyses of patients with β‐galactosidase deficiency and identified 46 mutation alleles including 9 novel mutations. We then examined the NOEV effect on mutant β‐galactosidase proteins by using six strains of patient‐derived skin fibroblast. We also performed mutagenesis to identify β‐galactosidase mutants that were responsive to NOEV and found that 22 out of 94 mutants were responsive. Computational structural analysis revealed the mode of interaction between human β‐galactosidase and NOEV. Moreover, we confirmed that NOEV reduced GM1 accumulation and ameliorated the impairments of lipid trafficking and protein degradation in β‐galactosidase deficient cells. These results provided further evidence to NOEV as a promising chaperone compound for β‐galactosidase deficiency. Hum Mutat 32:843–852, 2011.

Impairment of Ubiquitin–Proteasome System by E334K cMyBPC Modifies Channel Proteins, Leading to Electrophysiological Dysfunction

Cardiac arrhythmogenesis is regulated by channel proteins whose protein levels are in turn regulated by the ubiquitin-proteasome system (UPS). We have previously reported on UPS impairment induced by E334K cardiac myosin-binding protein C (cMyBPC), which causes hypertrophic cardiomyopathy (HCM) accompanied by arrhythmia. We hypothesized that UPS impairment induced by E334K cMyBPC causes accumulation of cardiac channel proteins, leading to electrophysiological dysfunction. Wild-type or E334K cMyBPC was overexpressed in HL-1 cells and primary cultured neonatal rat cardiac myocytes. The expression of E334K cMyBPC suppressed cellular proteasome activities. The protein levels of K(v)1.5, Na(v)1.5, Hcn4, Ca(v)3.2, Ca(v)1.2, Serca, RyR2, and Ncx1 were significantly higher in cells expressing E334K cMyBPC than in wild type. They further increased in cells pretreated with MG132 and had longer protein decays. The channel proteins retained the correct localization. Cells expressing E334K cMyBPC exhibited higher Ca(2+) transients and longer action potential durations (APDs), accompanied by afterdepolarizations and higher apoptosis. Those augments of APD and Ca(2+) transients were recapitulated by a simulation model. Although a Ca(2+) antagonist, azelnidipine, neither protected E334K cMyBPC from degradation nor affected E334K cMyBPC incorporation into the sarcomere, it normalized the APD and Ca(2+) transients and partially reversed the levels of those proteins regulating apoptosis, thereby attenuating apoptosis. In conclusion, UPS impairment caused by E334K cMyBPC may modify the levels of channel proteins, leading to electrophysiological dysfunction. Therefore, UPS impairment due to a mutant cMyBPC may partly contribute to the observed clinical arrhythmias in HCM patients.

Oxytocin for Male Subjects with Autism Spectrum Disorder and Comorbid Intellectual Disabilities: A Randomized Pilot Study.

Approximately half of autism spectrum disorder (ASD) individuals suffer from comorbid intellectual disabilities (IDs). Oxytocin (OXT) receptors are highly expressed in temporal lobe structures and are likely to play a modulatory role in excitatory/inhibitory balance, at least based on animal model findings. Thus, it is feasible that in the highly representative group of Kanner-type ASD subjects, OXT could have a beneficial effect on social communication and social interaction. The aim of this pilot study is to investigate the feasibility and adverse events, such as epilepsy, of the long-term administration of intranasal OXT for adolescent and adult ASD subjects with ID because such patients frequently have seizures. We also addressed the question on how to scale the OXT effects to the core symptoms of social deficits because of the relative difficulty in obtaining objective measurements. Twenty-nine males (aged 15–40 years old) participated in a randomized, double-blind, and placebo-controlled crossover study (each for 8 weeks) with OXT (16 IU/day). Except for seizures experienced by one participant, other serious adverse events did not occur. The primary and secondary outcomes measured using the Childhood Autism Rating Scale and several standard scales, respectively, revealed no difference between the OXT and placebo groups. Instead, in an exploratory analysis, the social interactions observed in the play sessions or in daily life were significantly more frequent in the initial half period in the OXT-first arm of the crossover trial. There were also significant correlations between the plasma OXT concentration and subscale scores for irritability on the Aberrant Behavior Checklist. In conclusion, this pilot study demonstrates that long-term administration of intranasal OXT is tolerable in a representative cohort of ASD individuals with ID and suggests that future multicenter trials of OXT are warranted and should include measurements of reciprocal social interactions based on daily life under closer surveillance for epilepsy. Trial registration: UMIN000007250.

Niemann‐Pick disease type C1 predominantly involving the frontotemporal region, with cortical and brainstem Lewy bodies: An autopsy case

Niemann‐Pick disease type C (NPC) is an autosomal recessive neurovisceral lipid storage disorder. Two disease‐causing genes (NPC1 and NPC2) have been identified. NPC is characterized by neuronal and glial lipid storage and NFTs. Here, we report a man with juvenile‐onset progressive neurological deficits, including pyramidal signs, ataxia, bulbar palsy, vertical supranuclear ophthalmoplegia, and psychiatric symptoms; death occurred at age 37 before definitive clinical diagnosis. Post mortem gross examination revealed a unique distribution of brain atrophy, predominantly in the frontal and temporal lobes. Microscopically, lipid storage in neurons and widely distributed NFTs were observed. Lipid storage cells appeared in systemic organs and filipin staining indicated intracellular cholesterol accumulation in hepatic macrophages. Electron microscopy revealed accumulation of lipids and characteristic oligolamellar inclusions. These findings suggested an NPC diagnosis. Neuronal loss and gliosis were frequently accompanied by NFTs and occurred in the frontal and temporal cortices, hippocampus, amygdala, basal forebrain, basal ganglia, thalamus, substantia nigra and brain stem nuclei. Lewy bodies (LBs) were observed in most, but not all, regions where NFTs were evident. In contrast, neuronal lipid storage occurred in more widespread areas, including the parietal and occipital cortices where neurodegeneration with either NFTs or LBs was minimal. Molecular genetic analysis demonstrated that the patient had compound heterozygous mutations in the cysteine‐rich loop (A1017T and Y1088C) of the NPC1 gene. To our knowledge there has been no previous report of the A1017T mutation. The pathological features of this patient support the notion that NPC has an aspect of α‐synucleinopathy, and long‐term survivors of NPC may develop a frontotemporal‐predominant distribution of brain atrophy.

Lack of AKT activation in lung cancer cells with EGFR mutation is a novel marker of cetuximab sensitivity.

Epidermal growth factor receptor (EGFR) mutation is the best marker of sensitivity to the EGFR tyrosine kinase inhibitor gefitinib, but a marker for the anti-EGFR antibody cetuximab has not been identified in lung cancer. The present study investigated markers for sensitivity to cetuximab. Sensitivity to cetuximab and gefitinib was compared with EGFR expression, EGFR and KRAS mutation, and EGFR gene copy numbers in lung cancer cell lines. We also studied the effect of these agents on the activation of EGFR, ERK, AKT, and STAT3 in cetuximab-sensitive and -resistant cell lines. We found one cetuximab-sensitive cell line with EGFR mutation among 19 lung cancer cell lines. Analysis of molecules downstream from EGFR revealed that AKT phosphorylation was suppressed in this cell line. Augmentation of AKT phosphorylation by transfection of a plasmid induced resistance to cetuximab. Acquisition of cetuximab resistance was associated with AKT activation in this cell line, while pharmacological inhibition of AKT markedly enhanced the growth inhibitory effect of cetuximab. Dephosphorylation of AKT in association with EGFR mutation is a candidate marker for sensitivity to cetuximab, and combined use of an AKT pathway inhibitor with cetuximab could be a novel therapeutic strategy for lung cancer.

Genotype/phenotype of 6 Chinese cases with Niemann–Pick disease type C

UNLABELLED Niemann-Pick disease type C (NP-C), caused by mutations of either NPC1 or NPC2 gene, is an inherited lysosomal lipid storage disorder that is difficult to be diagnosed and treated. NP-C is rarely reported in China and so far very few literatures are available for Chinese clinical workers. To better characterize this disease in China and improve genetic counseling, mutational analyses of NPC1 gene were carried out in 6 unrelated Chinese patients. METHODS Clinical data of the probands from 2007 to 2010 were collected and analyzed. All exons of NPC1 were analyzed by direct sequencing. RESULTS The six cases, four males and two females, included three cases of late infantile subtype and three cases of juvenile subtype. Case one and case six had siblings who suffered from the same disease. The onset of clinical symptoms varied from three to ten years old, and they included progressive cognitive and language impairment, and motion retrogradation. All were caught by focal or generalized seizures from one to four years after the onset. Vertical supranuclear gaze palsy, dysarthria, dysphagia, internal rotation and adduction of bilateral hands and splenomegaly occurred gradually during the disease progression. Five patients had laughter-cataplexy. MRI indicated mild brain atrophy. Sea blue cells and Niemann-Pick cells were presented in bone marrow smears. Activity of acid sphingomyelinase was normal or only slightly lower than controls. Supporting and symptomatic treatments could improve some of the clinical signs. We identified 10 different NPC1 mutations were identified in 12/12 alleles, 3 of which are described for the first time. All mutations were missense mutations, which located throughout the gene with five clustering in the cysteine-rich luminal domain. Homozygous mutation of S865L correlated with a relatively severe juvenile neurological form. CONCLUSIONS NP-C is a rare autosomal recessive lysosomal storage disease that affects intellectual development of children, causing dementia, vegetative state and eventual death. The awareness of NP-C should be raised in the Chinese population. The typical clinical features of this disease include vertical supranuclear gaze palsy, seizures and cataplexy. Laboratory features include the presence of sea blue cells and Niemann-Pick cells in bone marrow smears. NPC1 mutation can be identified in most of these patients and most of them are missense mutations.

Two deletion mutations in the hydroxymethylbilane synthase gene in two unrelated Japanese patients with acute intermittent porphyria

AbstractAcute intermittent porphyria (AIP) is an autosomal dominant inherited disease caused by a decreased activity of hydroxymethylbilane synthase (HMBS). Regarding the abnormalities of the HMBS gene, many different mutations have been reported worldwide; however, few families from Japan have been studied. In this work, we investigated the presence of mutations in two unrelated Japanese patients with AIP. Mutational analysis was performed using the polymerase chain reaction-single strand conformation polymorphism (SSCP) method, followed by DNA sequencing. Reliable restriction enzyme cleavage assays were also established for the pedigree analyses. Unique SSCP patterns were noted in exons 12 and 15 of the HMBS gene. Sequencing revealed different mutations in each patient: a two-base deletion of CT at nucleotide 730–731 (730delCT), and also a two-base deletion of CA at position 982–983 (982delCA). Both of the deletion mutations lead to truncated proteins with an abnormal C-terminus, which would be expected to decrease the stability and/or activity of HMBS. Using the cleavage assays, we were able to definitively identify gene carriers in the family. This study adds a novel mutation to those that have been previously reported, and emphasizes that molecular analysis would be very useful not only for the identification of asymptomatic gene carriers in the family but also for the detection of ancestral founders in porphyria families.

Topographical features of the sensory-evoked responses in malformed brains.

To reveal the functional organization of the somatosensory area in the dysgenetic cortex, somatosensory-evoked potentials were examined in seven patients with congenital brain anomalies diagnosed by magnetic resonance imaging, including six patients in whom multichannel recordings over the scalp were used. In four patients with polymicrogyria/pachygyria and two with lissencephaly, the early cortical responses, frontal P20 and parietal N20, were absent in the cortex contralateral to the stimulated side. The first cortical response was a positive wave that appeared predominantly over the centroparietal area in five patients, and in the frontal area in the other patient with polymicrogyria/pachygyria. These findings suggest that the differentiated somatosensory function is distributed normally in the centroparietal cortex in most cases of widespread cortical dysplasia. However, the absence of P20/N20 may indicate a hypoplastic central sulcus or functionally undifferentiated subdivision of the somatosensory cortex in these patients. The absence of cortical responses in the patient with holoprosencephaly may correspond with growth failure of the thalamocortical afferent projections in this disorder.

Variation analysis of β3‐adrenergic receptor and melanocortin‐4 receptor genes in childhood obesity

Background: Decreased energy expenditure and increased food intake are principal causes for obesity. In the present study, genotypes of β3‐adrenergic receptor (β3AR) and of melanocortin‐4 receptor (MC4R), both of which are believed to have a close link to the cause of obesity, were analyzed and compared with phenotypes of childhood obesity.