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We previously performed genetic analysis in six unrelated families with infantile limb pain episodes, characterized by cold-induced deterioration and mitigation in adolescence, and reported two new mutations p.R222H/S in SCN11A responsible for these episodes. As no term described this syndrome (familial episodic pain: FEP) in Japanese, we named it as"". In the current study, we recruited an additional 42 new unrelated Japanese FEP families, between March 2016 and March 2018, and identified a total of 11 mutations in SCN11A: p.R222H in seven families, and p.R225C, p.F814C, p.F1146S, or p.V1184A, in independent families. A founder mutation, SCN11A p.R222H was confirmed to be frequently observed in patients with FEP in the Tohoku region of Japan. We also identified two novel missense variants of SCN11A, p.F814C and p.F1146S. To evaluate the effects of these latter two mutations, we generated knock-in mouse models harboring p.F802C (F802C) and p.F1125S (F1125S), orthologues of the human p.F814C and p.F1146S, respectively. We then performed electrophysiological investigations using dorsal root ganglion neurons dissected from the 6-8 week-old mice. Dissected neurons of F802C and F1125S mice showed increased resting membrane potentials and firing frequency of the action potentials (APs) by high input-current stimulus compared with WT mice. Furthermore, the firing probability of evoked APs increased in low stimulus input in F1125S mice, whereas several AP parameters and current threshold did not differ significantly between either of the mutations and WT mice. These results suggest a higher level of excitability in the F802C or F1125S mice than in WT, and indicate that these novel mutations are gain of function mutations. It can be expected that a considerable number of potential patients with FEP may be the result of gain of function SCN11A mutations.

Adiponectin, a metabolically-active cytokine secreted from adipose tissue, is reported to have anti-apoptotic effects on β-cells as well as anti-hyperglycemic effects through adiponectin receptor signaling. However, the anti-apoptotic effects of adiponectin on β-cells have not been confirmed in established diabetic models, and the anti-hyperglycemic effects and their associated signal cascades remain controversial. To investigate the effects of adiponectin on β-cell protection and its down-stream signaling events, we have generated β-cell-specific rat insulin promoter (RIP)-AdipoR1 transgenic mice (AdipoR1 mice), in which the adiponectin receptor, AdipoR1, is overexpressed in β-cells in a manner synchronous with insulin demand. AdipoR1 mice were then mated with Akita mice, a diabetes model in which β-cell apoptosis results from endoplasmic reticulum (ER) stress. AdipoR1 protein expression and localization in islets from AdipoR1 mice as well as in an AdipoR1-transfected mouse insulinoma cell line were confirmed, as was the activation of both AMPK and Akt in AdipoR1 mice by adiponectin. Nevertheless, there were no significant differences in Ad lib feed and fasting blood glucose levels, or in glucose tolerance tests, between Akita mice [Ins2Akita (C96Y) +/- mouse model] and AdipoR1/Akita and from 4 weeks to 10 weeks of age. Similarly, pancreatic insulin contents of AdipoR1/Akita mice were not significantly different from those in Akita mice from 15 to 20 weeks of age, but they were significantly lower than in wild-type mice. Immunostaining for insulin and subsequent electron microscopy showed that β-cell destruction in AdipoR1/Akita mice was not markedly improved in comparison with that in Akita mice. Serum adiponectin concentrations were confirmed to be extremely high (> 30 μg / ml) compared with the Kd value (0.06 μg / ml) in all mouse groups at 15 to 20 weeks of age. Therefore, although the physiological levels of adiponectin are sufficient to activate AMPK and Akt when AdipoR1 is overexpressed in β-cells, yet adiponectin cannot protect β-cells in Akita mice from ER stress-induced destruction.

The genetic architecture of coronary artery disease has not been fully elucidated, especially in Asian countries. Moyamoya disease is a progressive cerebrovascular disease that is reported to be complicated by coronary artery disease. Because most Japanese patients with moyamoya disease carry the p.R4810K variant of the ring finger 213 gene (RNF213), this may also be a risk factor for coronary artery disease; however, this possibility has never been tested.We genotyped the RNF213 p.R4810K variant in 956 coronary artery disease patients and 716 controls and tested the association between p.R4810K and coronary artery disease. We also validated the association in an independent population of 311 coronary artery disease patients and 494 controls. In the replication study, the p.R4810K genotypes were imputed from genome-wide genotyping data based on the 1000 Genomes Project. We used multivariate logistic regression analyses to adjust for well-known risk factors such as dyslipidemia and smoking habits. In the primary study population, the frequency of the minor variant allele was significantly higher in patients with coronary artery disease than in controls (2.04% vs. 0.98%), with an odds ratio of 2.11 (p = 0.017). Under a dominant model, after adjustment for risk factors, the association remained significant, with an odds ratio of 2.90 (95% confidence interval: 1.37-6.61; p = 0.005). In the replication study, the association was significant after adjustment for age and sex (odds ratio = 4.99; 95% confidence interval: 1.16-21.53; p = 0.031), although it did not reach statistical significance when further adjusted for risk factors (odds ratio = 3.82; 95% confidence interval: 0.87-16.77; p = 0.076).The RNF213 p.R4810K variant appears to be significantly associated with coronary artery disease in the Japanese population.

RNF213/Mysterin has been identified as a susceptibility gene for moyamoya disease, a cerebrovascular disease characterized by occlusive lesions in the circle of Willis. The p.R4810K (rs112735431) variant is a founder polymorphism that is strongly associated with moyamoya disease in East Asia. Many non-p.R4810K rare variants of RNF213 have been identified in white moyamoya disease patients, although the ethnic mutations have not been investigated in this population. In the present study, we screened for RNF213 variants in 19 Slovakian and Czech moyamoya disease patients. A total of 69 RNF213 coding exons were directly sequenced in 18 probands and one relative who suffered from moyamoya disease in Slovakia and the Czech Republic. We previously reported one proband harboring RNF213 p.D4013N. Results from the present study identified four rare variants other than p.D4013N (p.R4019C, p.E4042K, p.V4146A, and p.W4677L) in four of the patients. P.V4146A was determined to be a novel de novo mutation, and p.R4019C and p.E4042K were identified as double mutations inherited on the same allele. P.W4677L, found in two moyamoya disease patients and an unaffected subject in the same pedigree, was a rare single nucleotide polymorphism. Functional analysis showed that RNF213 p.D4013N, p.R4019C and p.V4146A-transfected human umbilical vein endothelial cells displayed significant lowered migration, and RNF213 p.V4146A significantly reduced tube formation, indicating that these are disease-causing mutations. Results from the present study identified RNF213 rare variants in 22.2% (4/18 probands) of Slovakian and Czech moyamoya disease patients, confirming that RNF213 may also be a major causative gene in a relative large population of white patients.

Painful peripheral neuropathy has been correlated with various voltage-gated sodium channel mutations in sensory neurons. Recently Nav1.9, a voltage-gated sodium channel subtype, has been established as a genetic influence for certain peripheral pain syndromes. In this study, we performed a genetic study in six unrelated multigenerational Japanese families with episodic pain syndrome. Affected participants (n = 23) were characterized by infantile recurrent pain episodes with spontaneous mitigation around adolescence. This unique phenotype was inherited in an autosomal-dominant mode. Linkage analysis was performed for two families with 12 affected and nine unaffected members, and a single locus was identified on 3p22 (LOD score 4.32). Exome analysis (n = 14) was performed for affected and unaffected members in these two families and an additional family. Two missense variants were identified: R222H and R222S in SCN11A. Next, we generated a knock-in mouse model harboring one of the mutations (R222S). Behavioral tests (Hargreaves test and cold plate test) using R222S and wild-type C57BL/6 (WT) mice, young (8-9 weeks old; n = 10-12 for each group) and mature (36-38 weeks old; n = 5-6 for each group), showed that R222S mice were significantly (p < 0.05) more hypersensitive to hot and cold stimuli than WT mice. Electrophysiological studies using dorsal root ganglion neurons from 8-9-week-old mice showed no significant difference in resting membrane potential, but input impedance and firing frequency of evoked action potentials were significantly increased in R222S mice compared with WT mice. However, there was no significant difference among Nav1.9 (WT, R222S, and R222H)-overexpressing ND7/23 cell lines. These results suggest that our novel mutation is a gain-of-function mutation that causes infantile familial episodic pain. The mouse model developed here will be useful for drug screening for familial episodic pain syndrome associated with SCN11A mutations.

Neonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults.Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53-3.66 μg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 μg/day for dinotefuran, and this was

Moyamoya disease is an idiopathic vascular disorder of intracranial arteries. Its susceptibility locus has been mapped to 17q25.3 in Japanese families, but the susceptibility gene is unknown.Genome-wide linkage analysis in eight three-generation families with moyamoya disease revealed linkage to 17q25.3 (P