Association of placental weight at birth with maternal whole blood concentration of heavy metals (cadmium, lead, mercury, selenium, and manganese): The Japan Environment and Children's Study (JECS).

BACKGROUND: Lifelong health is dependent on prenatal growth and development, influenced by the placental intrauterine environment. Charged with dual functions--exchange of oxygen and nutrients as well as a barrier against toxins--the placenta itself is susceptible to environmental exposure to heavy metals. OBJECTIVE: To examine the use of placenta weight as a biomarker for heavy metal exposure using a large Japanese cohort of pregnant women. METHODS: The placenta weight, as a biomarker of exposure to heavy metals (cadmium, lead, and mercury), was investigated using data from the Japan Environment and Children's Study (2011-2014). Selenium and manganese were included as factors directly affecting fetal growth or heavy metal toxicity. Maternal blood samples collected in the second or third trimester were used to measure heavy metal concentrations. The association between maternal blood metal concentrations and placenta weight was explored by applying Z scores and multivariable logistic regression analysis and classifying participants into quartiles (Q1, Q2, Q3, and Q4) according to metal concentrations. RESULTS: This study included a total of 73,005 singleton pregnant women who delivered via live births and met the inclusion criteria. The median heavy metal concentrations in the maternal whole blood were 0.662 ng/g cadmium, 5.85 ng/g lead, 3.61 ng/g mercury, 168 ng/g selenium, and 15.3 ng/g manganese. Regression analysis revealed a significant correlation between placenta weight Z scores and maternal blood metal concentrations: cadmium, 0.0660 (standard error = 0.0074, p < 0.001); selenium, -0.3137 (standard error = 0.0276, p < 0.001); and manganese, 0.1483 (standard error = 0.0110, p < 0.001). CONCLUSION: This study provides a robust examination of the association between heavy metal exposure and placenta weight. Cadmium and manganese showed a positive correlation with significant differences, whereas selenium showed a negative correlation. Essential elements notably affect placenta weight differently. No significant association was noted between lead or mercury and placenta weight.

Pediatric leukemia and maternal occupational exposure to anticancer drugs: the Japan Environment and Children's Study.

ABSTRACT: Occupational exposure to medical agents and ionizing radiation has been suggested as a possible risk factor for childhood cancer. However, the relationship between such exposure and pediatric malignant neoplasms has not yet been comprehensively studied. This cohort study aimed to investigate the association between parental occupational exposure to hazardous medical agents or ionizing radiation and the risk of childhood cancer in offspring. Data from a large birth cohort in Japan, which included 104 062 fetuses, were analyzed. The primary outcome was the development of leukemia or brain tumors diagnosed by community physicians during the first 3 years after birth. Exposure factors were medical agents, including anticancer agents, ionizing radiation, and anesthetics, handled by mothers during pregnancy or by fathers for 3 months before conception. The incidence of leukemia, but not of brain tumors, was higher in mothers exposed to anticancer drugs. Multivariable regression analysis showed that maternal exposure to anticancer drugs was associated with an increased risk of leukemia in offspring older than 1 year (adjusted relative risk, 7.99 [95% confidence interval, 1.98-32.3]). Detailed information obtained from medical certificates of patients with identified leukemia revealed no infant leukemia but acute lymphoblastic leukemias in the exposed group. Our findings suggest that maternal occupational exposure to anticancer drugs may be a potential risk factor for acute lymphoblastic leukemia in offspring older than 1 year. Effective prevention methods may be necessary to prevent maternal exposure to anticancer drugs and to reduce the risk of childhood malignant neoplasms.

Maternal Chronic Disease and Congenital Anomalies of the Kidney and Urinary Tract in Offspring: A Japanese Cohort Study.

RATIONALE & OBJECTIVE: Several maternal chronic diseases have been reported as risk factors for congenital anomalies of the kidney and urinary tract (CAKUT) in offspring. However, these investigations used case-control designs, and cases with isolated genitourinary CAKUT were not distinguished from cases in which CAKUT were present with extrarenal congenital anomalies (complicated CAKUT). We examined the association of maternal diseases with isolated and complicated CAKUT in offspring using data from a prospective cohort study. STUDY DESIGN: A nationwide prospective birth cohort study. SETTING & PARTICIPANTS: 100,239 children enrolled in the Japan Environment and Children's Study between January 2011 and March 2014 at 15 research centers. Physicians' diagnoses in mothers and children were collected from medical record transcripts and questionnaires. EXPOSURES: Medical histories of maternal noncommunicable diseases, including obesity, hypertension, diabetes mellitus, kidney disease, hyperthyroidism, hypothyroidism, psychiatric disease, epilepsy, cancer, and autoimmune disease. OUTCOMES: CAKUT diagnosed during the first 3 years of life, classified as isolated or complicated. ANALYTICAL APPROACH: Multivariable Poisson regression with generalized estimating equations accounting for clustering by clinical center. RESULTS: Among the 100,239 children, 560 (0.6%) had CAKUT, comprising 454 (81%) isolated and 106 (19%) complicated forms. The risk of isolated CAKUT was increased in children of mothers who experienced kidney disease (adjusted risk ratio [RR], 1.80 [95% CI, 1.12-2.91]) or cancer (RR, 2.11 [95% CI, 1.15-3.86]). Furthermore, the risk of complicated CAKUT was increased in children of mothers with diabetes mellitus (RR, 3.04 [95% CI, 1.64-5.61]). LIMITATIONS: Lack of standardization or prespecification of clinical definitions, diagnostic criteria, measurements, and testing. Genetic testing was not performed. CONCLUSIONS: Isolated CAKUTs and complicated CAKUTs were associated with different maternal diseases. The results may inform clinical management of pregnancy and highlight potential differences in the genesis of isolated and complicated forms of CAKUT.

[Environmental factors for the development of hematopoietic neoplasms in children].

Parental age at birth has been investigated in patients diagnosed with pediatric cancer. The Japan Children's Cancer Registry1985-2007 recruited 5,510 patients with leukemia and 8,782 with other cancers. The proportion of patients born to mother and father aged >40 years showed a higher trend in leukemia than that in other cancers (odds ratio [OR] 1.41, p=0.057), especially in <12-month-old infants born to mother aged >40 years (OR 2.55, p=0.031). We then divided 27,335 patients diagnosed in 1969-2006 into every 8-year birth cohorts to compare proportions of mothers with prenatal medical irradiation. The OR of leukemia was higher than that of other cancers in 1969-1976 (1.25) or 1977-1984 (1.39), which reached statistical significance. We have also studied caregiver's exposure to anticancer drugs. In 15 pediatric patients with cancer who received cyclophosphamide (CPM), the concentration was measured using mothers and medical staff's urine. Five of 7 infants' and 2 of 8 adolescent's mothers showed increased urine CPM levels. CPM was not detected in any medical staff's samples. Maternal exposure to anticancer drugs should also be considered. Efforts of reducing the genotoxicity in both infants and mothers are crucial for pediatric cancer prevention.

Infantile neuroblastoma and maternal occupational exposure to medical agents.

BACKGROUND: Healthcare workers are often exposed to hazardous agents and are at risk for adverse health consequences that affect not only themselves but also their infants. This study aimed to examine whether such occupational exposure increased the risk of childhood cancer in offspring. METHODS: We used the dataset of the Japan Environment and Children's Study, a nationwide birth cohort involving over 100,000 mother-child pairs. Information was obtained via successive questionnaires that were completed until the child turned 1 year of age. The parents were asked whether they occupationally handled medical agents during pregnancy. RESULTS: A total of 26 infants developed neoplasms: neuroblastoma, leukemia, and brain tumor. The incidence of neuroblastoma was significantly higher in infants whose mothers were exposed to radiation (3/2142: 140.1 per 100,000 population) than in those who were not (12/90,384: 13.3 per 100,000 population). Multivariable regression analyses revealed a close association between maternal irradiation and the development of neuroblastoma (adjusted incident rate ratio: 10.68 [95% confidence interval: 2.98‒38.27]). CONCLUSIONS: The present study demonstrated, for the first time, a potential association between maternal occupational exposure and the occurrence of neuroblastoma in offspring. Further studies involving the large pediatric cancer registries are needed to confirm these preliminary results. IMPACT: Healthcare workers are often exposed to hazardous agents and are at risk for adverse health consequences that affect not only themselves but also their infants. This study examined the association between such occupational exposure and offspring's cancers that developed until the age of 1 year. Maternal exposure to ionizing radiation was associated with infantile neuroblastoma in offspring. Further studies involving the large pediatric cancer registries are needed to confirm these preliminary results.

De novo p.G696S mutation in COL4A1 causes intracranial calcification and late-onset cerebral hemorrhage: A case report and review of the literature.

BACKGROUND: The collagen type IV alpha 1 chain (COL4A1) is an essential component of the basement membrane in small vessels. Pathogenic variants in COL4A1 cause perinatal cerebral hemorrhages in an autosomal-dominant fashion. However, little is known about the long-term outcomes of patients with mildly affecting COL4A1 mutations. CASE REPORT: We report a 17-year-old boy, who presented with recurrent intracranial hemorrhages in the periventricular white matter. He had been followed-up as a child with cerebral palsy bearing intracranial calcifications, developmental delay and epilepsy. Screening tests in infancy provided negative results for intrauterine infections. Severe motor and cognitive deficits persisted after admission. Carbazochrome was introduced on day 19 of admission, which appeared to prevent extension and reactivation of cerebral hemorrhages for over 6 months after discharge. RESULTS: Targeted sequencing of NOTCH3 and TREX1 excluded causal mutations in these genes. The whole-exome sequencing revealed that he carried a de novo mutation in COL4A1 (p.Gly696Ser). An overview of the literature for 345 cases with COL4A1 mutations supported evidence that p.Gly696Ser is associated with the unique phenotype of late-onset hemorrhage among patients with COL4A1-associated cerebral angiopathy. CONCLUSIONS: This case first demonstrates that infants with COL4A1-associated leukoencephalopathy and calcifications have a risk for developing the rupture of small vessels in the cerebral white matter after 10 years of age.

Psychometric profile of the Ages and Stages Questionnaires, Japanese translation.

BACKGROUND: This study assessed the psychometric profile of 10 questionnaires (every 6 months, from 6 to 60 months) from the Japanese translation of the Ages and Stages Questionnaires, third edition (J-ASQ-3). METHODS: Data from 439 children in a birth cohort were used to identify the J-ASQ-3 score distribution, establish cut-off scores, and calculate the instrument's internal consistency. Data were also collected from 491 outpatients to examine J-ASQ-3 test-retest reliability and concurrent validity, which was examined using the Kyoto Scale of Psychological Development (KSPD) and the Japanese version of the Denver Developmental Screening Test II (J-Denver II). Both the original and the alternative screening criteria of the ASQ-3 were used (failure in at least one and at least two domains, respectively). RESULTS: Cronbach's alpha for each J-ASQ-3 subscale on each questionnaire ranged from 0.45 to 0.89. Test-retest reliability was >0.75 for the subscales on almost all questionnaires. Concurrent validity was also adequate. In comparison with the screening results of the KSPD, the overall sensitivity and specificity were 96.0% and 48.8%, respectively, when the ASQ-3 original criterion was used, and 92.1% and 74.9%, respectively, when the alternative criterion was used. In comparison with the screening results of the J-Denver II, the overall sensitivity and specificity were 75.6% and 74.7%, respectively, when the ASQ-3 original criterion was used, and 56.3% and 93.0%, respectively, when the alternative criterion was used. CONCLUSIONS: This study quantified the psychometric profiles of the Japanese translations of 10 ASQ-3 questionnaires. We demonstrated the validity of the J-ASQ-3 and determined new cut-off scores. Further studies with larger samples from a greater range of locations are required to clarify the suitability of this tool for all Japanese children.

Associations between metal concentrations in whole blood and placenta previa and placenta accreta: the Japan Environment and Children's Study (JECS).

BACKGROUND: Placenta previa and placenta accreta associate with high morbidity and mortality for both mothers and fetus. Metal exposure may have relationships with placenta previa and placenta accreta. This study analyzed the associations between maternal metal (cadmium [Cd], lead [Pb], mercury [Hg], selenium [Se], and manganese [Mn]) concentrations and placenta previa and placenta accreta. METHODS: We recruited 17,414 women with singleton pregnancies. Data from a self-administered questionnaire regarding the first trimester and medical records after delivery were analyzed. Maternal blood samples were collected to measure metal concentrations. The subjects were classified into four quartiles (Q1, Q2, Q3, and Q4) according to metal concentrations. RESULTS: The odds ratio for placenta previa was significantly higher among subjects with Q4 Cd than those with Q1 Cd. The odds ratio for placenta previa was significantly higher for subjects with Q2 Pb than those with Q1 Pb. CONCLUSION: Participants with placenta previa had higher Cd concentrations. However, this study was cross-sectional and lacked important information related to Cd concentration, such as detailed smoking habits and sources of Cd intake. In addition, the subjects in this study comprised ordinary pregnant Japanese women, and it was impossible to observe the relationship between a wide range of Cd exposure and placenta previa. Therefore, epidemiological and experimental studies are warranted to verify the relationship between Cd exposure and pregnancy abnormalities.

An acute encephalopathy with reduced diffusion in BRAF-associated cardio-facio-cutaneous syndrome.

BACKGROUND: Cardio-facio-cutaneous syndrome (CFCS) is a rare genetic disorder characterized by cardiovascular anomalies, dysmorphic faces, ectodermal abnormalities and developmental delays. Mutations in BRAF and other RAS-MAPK pathway-associated genes are commonly identified in patients with CFCS. While this molecular pathway is known to be associated with neuro-inflammatory conditions, only one case with CFCS has been reported thus far to develop acute encephalopathy in childhood. CASE REPORT: A 3-year-old boy with dysmorphic features and mild psychomotor delay developed acute encephalopathy. After a 45-min long, generalized seizure, the magnetic resonance imaging revealed that the restricted diffusion signals spread to the bilateral subcortical white matters on day 1 of illness. Despite the 14 days of intensive care, the acute symptoms of encephalopathy left him intractable epilepsy and severe neurocognitive impairments. The whole-exome sequencing analysis identified a de novo heterozygous mutation of BRAF (NM_004333:p.Thr241Met) in this case. CONCLUSION: The present case suggests that the hyperactive condition of ERK signals might augment the development of acute encephalopathy and post-encephalopathic epilepsy in childhood.

Vascular pathomechanism in acute encephalopathy with biphasic seizures and late reduced diffusion.

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is a childhood-onset encephalopathy, but the precise pathophysiology remains unclear. We encountered a child with Moyamoya syndrome and AESD. He exhibited left-predominant stenosis of the middle cerebral artery (MCA), and later developed broad lesions in the left hemisphere, raising the possibility that insufficient blood supply relates to formation of the lesions. To test the hypothesis, we investigated the relationship between MCA volume and lesion extent in seven AESD children without preexisting diseases. The MCA volume and lesion extent were quantified with time of flight images for construction of magnetic resonance angiography and apparent diffusion coefficient maps, respectively. Lateralization indices ([right - left]/[right + left]) of the MCA volume and lesion extent were calculated. We found that the lateralization indices were negatively correlated (r = -0.786, p = .036), that is, when the MCA volume was smaller in one side than the other side, the lesions were likely to develop more extensively in the ipsilateral side than the contralateral side. This indicates the association of insufficient blood supply with the lesions. The present study provides the first observation to suggest the involvement of vascular mechanism in AESD and has potential implications for novel therapeutic approach.

The association between whole blood concentrations of heavy metals in pregnant women and premature births: The Japan Environment and Children's Study (JECS).

BACKGROUND: Heavy metals are widely distributed in the environment. Recent reports have demonstrated the risk of preterm birth following heavy metal exposure. Preterm births are classified as early and late, depending on the duration of pregnancy, and are associated with increased risk of congenital illnesses such as heart failure, asthma, etc. Particularly, early preterm births carry a higher risk of mortality; however, the differential effects of heavy metal exposure on early and late preterm births are unknown. OBJECTIVES: To analyze the association between maternal whole blood concentrations of heavy metals, such as cadmium (Cd), lead (Pb), mercury (Hg), selenium (Se), and manganese (Mn) that are common toxicants in Japan, and early and late preterm births. METHODS: The data of 14,847 pregnant women who were participants of the Japan Environment and Children's Study were used. Data of the self-questionnaire pertaining to the first trimester (T1), second/third trimester (T2), and medical records after delivery were analyzed. We divided preterm birth into two groups: early preterm (22 to < 34 weeks) and late preterm (34 to < 37 weeks). Maternal blood samples for measuring heavy metal concentrations were collected in T2 (pregnancy weeks: 14-39). The participants were classified into four quartiles (Q1-Q4) according to increasing heavy metal levels. RESULTS: The rate of preterm birth was 4.5%. After controlling for confounding factors, such as age, pre-pregnancy body mass index, smoking, partner's smoking, drinking habits, gravidity, parity, number of cesarean deliveries, uterine infections, household income, educational levels, and sex of infant, Cd levels were found, by multivariable logistic regression analysis, to be significantly associated with early preterm birth (p = 0.002), with odds ratio for early preterm birth of 1.91 (95% confidence interval: 1.12-3.27, P = 0.018) in subjects of Q4 compared with in subjects with term birth (≧ 37 weeks). CONCLUSION: Maternal blood Cd levels during pregnancy are positively associated with the risk of early preterm birth among Japanese women. Identification of the main source of maternal Cd exposure may contribute to the prevention of early preterm births and health maintenance of mothers and their infants in the future.

Variation in Men's Dietary Intake Between Occupations, Based on Data From the Japan Environment and Children's Study.

There has been increasing interest in dietary health promotion in the workplace. Although many previous studies have focused on dietary habits in specific occupations, variation between occupational groups requires clarification. The present study aimed to examine differences in food and nutrient intake between occupational groups, using detailed classification. A cross-sectional study was conducted using data from the Japan Environment and Children's Study. The study included 38,721 employed Japanese expectant fathers aged between 20 and 65 years. Dietary intake was assessed using a food frequency questionnaire. Occupations were categorized into 11 categories according to the Japan Standard Occupational Classification. Analysis of variance and analysis of covariance were performed to compare dietary intake of occupational groups. Logistic regression analysis was performed to examine the differences in adherence to dietary recommendations across occupations. Dietary intake differed significantly between occupations. Specific dietary intake was observed in security and agricultural workers, who tended to exhibit higher consumption levels for numerous foods and nutrients. In addition, relative to other workers, security workers showed higher intake of dairy products and calcium, and agricultural workers consumed larger amounts of pickles and salt. The study categorized occupations into detailed categories using the Japan Standard Occupational Classification, which facilitated the clarification of overall dietary trends across occupations and identification of specific dietary characteristics in individual occupations. The findings could aid in workplace health promotion.

Early-onset epileptic encephalopathy and severe developmental delay in an association with de novo double mutations in NF1 and MAGEL2.

Advance in the exome-wide sequencing analysis contributes to identifying hundreds of genes that are associated with early-onset epileptic encephalopathy and neurodevelopmental disorders. On the basis of massive sequencing data, functional interactions among different genes are suggested to explain the common molecular pathway underlying the pathogenic process of these disorders. However, the relevance of such interactions with the phenotypic severity or variety in an affected individual remains elusive. In this report, we present a 45-year-old woman with neurofibromatosis type 1 (NF1), infantile-onset epileptic encephalopathy, and severe developmental delay. Whole-exome sequencing identified de novo pathogenic mutations in NF1 and the Schaaf-Yang syndrome-associated gene, MAGEL2. Literature-curated interaction data predicted that NF1 and MAGEL2 proteins were closely connected in this network via their common interacting proteins. Direct conversion of fibroblasts into neurons in vitro showed that neuronal cells from 9 patients with NF1 expressed significantly lower levels of MAGEL2 (54%, p = 0.0047) than those from healthy individuals. These data provide the first evidence that pathogenic mutations of NF1 deregulate the expression of other neurodevelopmental disease-associated genes. De novo mutations in multiple genes may lead to severe developmental phenotypes through their cumulative effects or synergistic interactions.

Sustained endocrine profiles of a girl with WAGR syndrome.

BACKGROUND: Wilms tumor, aniridia, genitourinary anomalies and mental retardation (WAGR) syndrome is a rare genetic disorder caused by heterozygous deletions of WT1 and PAX6 at chromosome 11p13. Deletion of BDNF is known eto be associated with hyperphagia and obesity in both humans and animal models; however, neuroendocrine and epigenetic profiles of individuals with WAGR syndrome remain to be determined. CASE PRESENTATION: We report a 5-year-old girl with the typical phenotype of WAGR syndrome. She showed profound delays in physical growth, motor and cognitive development without signs of obesity. Array comparative genome hybridization (CGH) revealed that she carried a 14.4 Mb deletion at 11p14.3p12, encompassing the WT1, PAX6 and BDNF genes. She experienced recurrent hypoglycemic episodes at 5 years of age. Insulin tolerance and hormonal loading tests showed normal hypothalamic responses to the hypoglycemic condition and other stimulations. Methylation analysis for freshly prepared DNA from peripheral lymphocytes using the pyro-sequencing-based system showed normal patterns of methylation at known imprinting control regions. CONCLUSIONS: Children with WAGR syndrome may manifest profound delay in postnatal growth through unknown mechanisms. Epigenetic factors and growth-associated genes in WAGR syndrome remain to be characterized.

A childhood-onset intestinal toxemia botulism during chemotherapy for relapsed acute leukemia.

BACKGROUND: Botulism is a potentially fatal infection characterized by progressive muscle weakness, bulbar paralysis, constipation and other autonomic dysfunctions. A recent report suggested that cancer chemotherapy might increase the risk for the intestinal toxemia botulism in both adults and children. CASE PRESENTATION: We report a 5-year-old boy, who developed general muscle weakness, constipation, ptosis and mydriasis during the third induction therapy for relapsed acute myeloid leukemia. He had recent histories of multiple antibiotic therapy for bacteremia and intake of well water at home. Repeated bacterial cultures identified Clostridium botulinum producing botulinum neurotoxin A. Botulinum toxin A was isolated from his stools at 17, 21, and 23 days after the onset. Symptoms were self-limiting, and were fully recovered without anti-botulinum toxin globulin therapy. CONCLUSION: This is the second report of a pediatric case with cancer chemotherapy-associated intestinal toxemia botulism. Our case provides further evidence that the immunocompromised status due to anti-cancer treatments increases the risk for the development of botulism at all ages in childhood.

Mutations in genes encoding polycomb repressive complex 2 subunits cause Weaver syndrome.

Weaver syndrome (WS) is a rare congenital overgrowth disorder caused by heterozygous mutations in EZH2 (enhancer of zeste homolog 2) or EED (embryonic ectoderm development). EZH2 and EED are core components of the polycomb repressive complex 2 (PRC2), which possesses histone methyltransferase activity and catalyzes trimethylation of histone H3 at lysine 27. Here, we analyzed eight probands with clinically suspected WS by whole-exome sequencing and identified three mutations: a 25.4-kb deletion partially involving EZH2 and CUL1 (individual 1), a missense mutation (c.707G>C, p.Arg236Thr) in EED (individual 2), and a missense mutation (c.1829A>T, p.Glu610Val) in SUZ12 (suppressor of zeste 12 homolog) (individual 3) inherited from her father (individual 4) with a mosaic mutation. SUZ12 is another component of PRC2 and germline mutations in SUZ12 have not been previously reported in humans. In vitro functional analyses demonstrated that the identified EED and SUZ12 missense mutations cause decreased trimethylation of lysine 27 of histone H3. These data indicate that loss-of-function mutations of PRC2 components are an important cause of WS.

De novo p.Arg756Cys mutation of ATP1A3 causes an atypical form of alternating hemiplegia of childhood with prolonged paralysis and choreoathetosis.

BACKGROUND: Alternating hemiplegia of childhood (AHC) is a rare neurological disorder that manifests recurrent attacks of hemiplegia, oculogyric, and choreoathetotic involuntary movements. De novo mutations in ATP1A3 cause three types of neurological diseases: AHC; rapid-onset dystonia-Parkinsonism (RDP); and cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss (CAPOS) syndromes. It remains to be determined whether or not a rare mutation in ATP1A3 may cause atypical phenotypes. CASE PRESENTATION: A 7-year-old boy presented with recurrent symptoms of generalized paralysis since 1 year and 5 months of age. Hypotonia, dystonia, and choreoathetosis persisted with exacerbation under febrile conditions, but no cerebellar ataxia had ever evolved in 6 years. Whole-exome sequencing (WES) was performed to determine his genetic background, and mutations were validated by the Sanger method. Crude protein extracts were prepared from the cultured cells, and expression of the wild-type or mutant ATP1A3 proteins were analyzed by Western blotting. WES identified a de novo pathogenic mutation in ATP1A3 (c.2266C > T:p.R756C) for this patient. A literature overview of two reported cases with p.R756C and p.R756H mutations showed both overlapping and distinct phenotypes when compared with those of the present case. The expression of the mutant form (R756C) of ATP1A3 did not differ markedly from that of the wild-type and D801N proteins. CONCLUSIONS: This study confirmed that p.R756C mutation of ATP1A3 cause atypical forms of AHC-associated disorders. The wide spectra of neurological phenotypes in AHC are linked to as-yet-unknown deficits in the functions of mutant ATP1A3.

Hyperactive mTOR signals in the proopiomelanocortin-expressing hippocampal neurons cause age-dependent epilepsy and premature death in mice.

Epilepsy is a frequent comorbidity in patients with focal cortical dysplasia (FCD). Recent studies utilizing massive sequencing data identified subsets of genes that are associated with epilepsy and FCD. AKT and mTOR-related signals have been recently implicated in the pathogenic processes of epilepsy and FCD. To clarify the functional roles of the AKT-mTOR pathway in the hippocampal neurons, we generated conditional knockout mice harboring the deletion of Pten (Pten-cKO) in Proopiomelanocortin-expressing neurons. The Pten-cKO mice developed normally until 8 weeks of age, then presented generalized seizures at 8-10 weeks of age. Video-monitored electroencephalograms detected paroxysmal discharges emerging from the cerebral cortex and hippocampus. These mice showed progressive hypertrophy of the dentate gyrus (DG) with increased expressions of excitatory synaptic markers (Psd95, Shank3 and Homer). In contrast, the expression of inhibitory neurons (Gad67) was decreased at 6-8 weeks of age. Immunofluorescence studies revealed the abnormal sprouting of mossy fibers in the DG of the Pten-cKO mice prior to the onset of seizures. The treatment of these mice with an mTOR inhibitor rapamycin successfully prevented the development of seizures and reversed these molecular phenotypes. These data indicate that the mTOR pathway regulates hippocampal excitability in the postnatal brain.

Moyamoya disease susceptibility gene RNF213 links inflammatory and angiogenic signals in endothelial cells.

Moyamoya disease (MMD) is a cerebrovascular disorder characterized by occlusive lesions of the circle of Willis. To date, both environmental and genetic factors have been implicated for pathogenesis of MMD. Allelic variations in RNF213 are known to confer the risk of MMD; however, functional roles of RNF213 remain to be largely elusive. We herein report that pro-inflammatory cytokines, IFNG and TNFA, synergistically activated transcription of RNF213 both in vitro and in vivo. Using various chemical inhibitors, we found that AKT and PKR pathways contributed to the transcriptional activation of RNF213. Transcriptome-wide analysis and subsequent validation with quantitative PCR supported that endogenous expression of cell cycle-promoting genes were significantly decreased with knockdown of RNF213 in cultured endothelial cells. Consistently, these cells showed less proliferative and less angiogenic profiles. Chemical inhibitors for AKT (LY294002) and PKR (C16) disrupted their angiogenic potentials, suggesting that RNF213 and its upstream pathways cooperatively organize the process of angiogenesis. Furthermore, RNF213 down-regulated expressions of matrix metalloproteases in endothelial cells, but not in fibroblasts or other cell types. Altogether, our data illustrate that RNF213 plays unique roles in endothelial cells for proper gene expressions in response to inflammatory signals from environments.