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1.
J Biol Chem ; 300(4): 107138, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38447794

RESUMO

Short tandem repeats are inherently unstable during DNA replication depending on repeat length, and the expansion of the repeat length in the human genome is responsible for repeat expansion disorders. Pentanucleotide AAGGG and ACAGG repeat expansions in intron 2 of the gene encoding replication factor C subunit 1 (RFC1) cause cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) and other phenotypes of late-onset cerebellar ataxia. Herein, we reveal the structural polymorphism of the RFC1 repeats associated with CANVAS in vitro. Single-stranded AAGGG repeat DNA formed a hybrid-type G-quadruplex, whereas its RNA formed a parallel-type G-quadruplex with three layers. The RNA of the ACAGG repeat formed hairpin structure comprising C-G and G-C base pairs with A:A and GA:AG mismatched repeats. Furthermore, both pathogenic repeat RNAs formed more rigid structures than those of the nonpathogenic repeat RNAs. These findings provide novel insights into the structural polymorphism of the RFC1 repeats, which may be closely related to the disease mechanism of CANVAS.

2.
Sci Rep ; 13(1): 18690, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907687

RESUMO

The recruitment maneuver (RM) combined with PEEP to prevent atelectasis have beneficial effects. However, the change in tidal volume (VT) due to RM combined with PEEP in pediatric patients during the induction of general anesthesia is unknown. Therefore, we assessed the effects of RM combined with PEEP on VT. Pediatric patients were divided into three groups: infants, preschool children, and school children. The RM was performed by maintaining pressure control continuous mandatory ventilation (PC-CMV) with a 15 cmH2O and PEEP increase of 5 cmH2O. VT, respiratory function and hemodynamics were monitored before and after RM combined with PEEP. VT (mL) /ideal body weight (kg) before vs. after RM combined with PEEP were 9 vs 12 mL/kg (p < 0.05) in the infants, 9 vs 11 mL/kg (p < 0.05) in the preschool children, 8 vs 10 mL/kg (p < 0.05) in the school children, respectively. HR and BP before and after RM combined with PEEP increased by 2-3% and decreased by 4-7% in all groups. RM combined with PEEP resulted in an increase in VT per ideal body weight (1.1-1.2%). Therefore, this RM combined with PEEP method might improve the lung function in pediatric patients.


Assuntos
Respiração com Pressão Positiva , Respiração Artificial , Humanos , Criança , Volume de Ventilação Pulmonar , Respiração Artificial/métodos , Respiração com Pressão Positiva/métodos , Anestesia Geral
3.
J Clin Invest ; 133(22)2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707954

RESUMO

Expansion of CAG and CTG (CWG) triplet repeats causes several inherited neurological diseases. The CWG repeat diseases are thought to involve complex pathogenic mechanisms through expanded CWG repeat-derived RNAs in a noncoding region and polypeptides in a coding region, respectively. However, an effective therapeutic approach has not been established for the CWG repeat diseases. Here, we show that a CWG repeat DNA-targeting compound, cyclic pyrrole-imidazole polyamide (CWG-cPIP), suppressed the pathogenesis of coding and noncoding CWG repeat diseases. CWG-cPIP bound to the hairpin form of mismatched CWG DNA, interfering with transcription elongation by RNA polymerase through a preferential activity toward repeat-expanded DNA. We found that CWG-cPIP selectively inhibited pathogenic mRNA transcripts from expanded CWG repeats, reducing CUG RNA foci and polyglutamine accumulation in cells from patients with myotonic dystrophy type 1 (DM1) and Huntington's disease (HD). Treatment with CWG-cPIP ameliorated behavioral deficits in adeno-associated virus-mediated CWG repeat-expressing mice and in a genetic mouse model of HD, without cytotoxicity or off-target effects. Together, we present a candidate compound that targets expanded CWG repeat DNA independently of its genomic location and reduces both pathogenic RNA and protein levels. CWG-cPIP may be used for the treatment of CWG repeat diseases and improvement of clinical outcomes.


Assuntos
Doença de Huntington , Distrofia Miotônica , Humanos , Animais , Camundongos , RNA/genética , Expansão das Repetições de Trinucleotídeos/genética , Nylons/farmacologia , Distrofia Miotônica/genética , Repetições de Trinucleotídeos , Doença de Huntington/tratamento farmacológico , Doença de Huntington/genética , DNA , Imidazóis/farmacologia
4.
Sci Total Environ ; 884: 163805, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37142023

RESUMO

A four-week-long field intervention experiment was conducted in twenty-nine bedrooms with extract ventilation systems and air inlet vents. During the first week no interventions took place. In the three weeks that followed, each participant slept for one week under a low, moderate, and high ventilation rate condition in a balanced order. These conditions were established by covertly altering the fan speed of the exhaust ventilation system without changing other settings. Participants were not informed when or even whether the changes to bedroom ventilation would be executed. The bedroom environmental quality was monitored continuously and sleep quality was monitored using wrist-worn trackers. Tests of cognitive performance were conducted in the evening and morning. In twelve bedrooms where clear differences between the three ventilation conditions occurred, as indicated by the measured CO2 concentrations, participants had significantly less deep sleep, more light sleep and more awakenings at lower ventilation rate conditions. In twenty-three bedrooms where a clear difference in ventilation rate between the high and low ventilation conditions was observed, as confirmed by the measured CO2 concentrations, the deep sleep was significantly shorter in the low ventilation rate condition. No differences in cognitive performance between conditions were observed. At lower ventilation rate conditions, the concentrations of CO2 increased, as did the relative humidity, while bedroom temperatures remained unchanged. The present results, which were obtained in actual bedrooms, confirm the findings in previous studies of a positive effect of increased ventilation on sleep quality. Further studies with larger populations and better control of bedroom conditions, particularly ventilation, are required.


Assuntos
Poluição do Ar em Ambientes Fechados , Qualidade do Sono , Humanos , Método Simples-Cego , Dióxido de Carbono/análise , Sono , Temperatura , Ventilação/métodos , Poluição do Ar em Ambientes Fechados/prevenção & controle , Poluição do Ar em Ambientes Fechados/análise
5.
J Neurotrauma ; 40(15-16): 1694-1706, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029810

RESUMO

The difficulty of accurately identifying patients who would benefit from promising treatments makes it challenging to prove the efficacy of novel treatments for traumatic brain injury (TBI). Although machine learning is being increasingly applied to this task, existing binary outcome prediction models are insufficient for the effective stratification of TBI patients. The aim of this study was to develop an accurate 3-class outcome prediction model to enable appropriate patient stratification. To this end, retrospective balanced data of 1200 blunt TBI patients admitted to six Japanese hospitals from January 2018 onwards (200 consecutive cases at each institution) were used for model training and validation. We incorporated 21 predictors obtained in the emergency department, including age, sex, six clinical findings, four laboratory parameters, eight computed tomography findings, and an emergency craniotomy. We developed two machine learning models (XGBoost and dense neural network) and logistic regression models to predict 3-class outcomes based on the Glasgow Outcome Scale-Extended (GOSE) at discharge. The prediction models were developed using a training dataset with n = 1000, and their prediction performances were evaluated over two validation rounds on a validation dataset (n = 80) and a test dataset (n = 120) using the bootstrap method. Of the 1200 patients in aggregate, the median patient age was 71 years, 199 (16.7%) exhibited severe TBI, and emergency craniotomy was performed on 104 patients (8.7%). The median length of stay was 13.0 days. The 3-class outcomes were good recovery/moderate disability for 709 patients (59.1%), severe disability/vegetative state in 416 patients (34.7%), and death in 75 patients (6.2%). XGBoost model performed well with 69.5% sensitivity, 82.5% accuracy, and an area under the receiver operating characteristic curve of 0.901 in the final validation. In terms of the receiver operating characteristic curve analysis, the XGBoost outperformed the neural network-based and logistic regression models slightly. In particular, XGBoost outperformed the logistic regression model significantly in predicting severe disability/vegetative state. Although each model predicted favorable outcomes accurately, they tended to miss the mortality prediction. The proposed machine learning model was demonstrated to be capable of accurate prediction of in-hospital outcomes following TBI, even with the three GOSE-based categories. As a result, it is expected to be more impactful in the development of appropriate patient stratification methods in future TBI studies than conventional binary prognostic models. Further, outcomes were predicted based on only clinical data obtained from the emergency department. However, developing a robust model with consistent performance in diverse scenarios remains challenging, and further efforts are needed to improve generalization performance.


Assuntos
Lesões Encefálicas Traumáticas , Estado Vegetativo Persistente , Humanos , Idoso , Estudos Retrospectivos , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/terapia , Prognóstico , Aprendizado de Máquina
6.
Sci Adv ; 9(8): eade2035, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827365

RESUMO

Consecutive guanine RNA sequences can adopt quadruple-stranded structures, termed RNA G-quadruplexes (rG4s). Although rG4-forming sequences are abundant in transcriptomes, the physiological roles of rG4s in the central nervous system remain poorly understood. In the present study, proteomics analysis of the mouse forebrain identified DNAPTP6 as an RNA binding protein with high affinity and selectivity for rG4s. We found that DNAPTP6 coordinates the assembly of stress granules (SGs), cellular phase-separated compartments, in an rG4-dependent manner. In neurons, the knockdown of DNAPTP6 diminishes the SG formation under oxidative stress, leading to synaptic dysfunction and neuronal cell death. rG4s recruit their mRNAs into SGs through DNAPTP6, promoting RNA self-assembly and DNAPTP6 phase separation. Together, we propose that the rG4-dependent phase separation of DNAPTP6 plays a critical role in neuronal function through SG assembly.


Assuntos
Quadruplex G , RNA , Animais , Camundongos , RNA/química , Grânulos de Estresse , RNA Mensageiro/genética , Neurônios/metabolismo
7.
Mol Oncol ; 17(6): 1148-1166, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36688680

RESUMO

Tetraploidy is a hallmark of cancer cells, and tetraploidy-selective cell growth suppression is a potential strategy for targeted cancer therapy. However, how tetraploid cells differ from normal diploids in their sensitivity to anti-proliferative treatments remains largely unknown. In this study, we found that tetraploid cells are significantly more susceptible to inhibitors of a mitotic kinesin (CENP-E) than are diploids. Treatment with a CENP-E inhibitor preferentially diminished the tetraploid cell population in a diploid-tetraploid co-culture at optimum conditions. Live imaging revealed that a tetraploidy-linked increase in unsolvable chromosome misalignment caused substantially longer mitotic delay in tetraploids than in diploids upon moderate CENP-E inhibition. This time gap of mitotic arrest resulted in cohesion fatigue and subsequent cell death, specifically in tetraploids, leading to tetraploidy-selective cell growth suppression. In contrast, the microtubule-stabilizing compound paclitaxel caused tetraploidy-selective suppression through the aggravation of spindle multipolarization. We also found that treatment with a CENP-E inhibitor had superior generality to paclitaxel in its tetraploidy selectivity across a broader spectrum of cell lines. Our results highlight the unique properties of CENP-E inhibitors in tetraploidy-selective suppression and their potential use in the development of tetraploidy-targeting interventions in cancer.


Assuntos
Proteínas Cromossômicas não Histona , Neoplasias , Tetraploidia , Humanos , Linhagem Celular , Microtúbulos , Mitose , Paclitaxel/farmacologia , Proteínas Cromossômicas não Histona/antagonistas & inibidores
8.
Yakugaku Zasshi ; 142(5): 513-519, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-35491157

RESUMO

Genetic information is replicated and transmitted from a parent cell to two identical daughter cells through mitotic cell division. To accomplish this dynamic process with high accuracy and precision, various motor proteins work in a concerted manner. Especially in the metaphase, mitotic chromosomes are delivered by the motor protein of centromere-associated protein E (CENP-E) to the cell equatorial plane (metaphase plate) along mitotic spindles. However, the critical functional failure of CENP-E can activate the spindle assembly checkpoint through the misalignment of chromosomes at the metaphase plate. In this symposium review, the reversibly photoswitchable CENP-E inhibitor PCEI-HU (5) is reported. Compound 5 exhibited almost quantitative trans-cis photoisomerization of the arylazopyrazole photoswitch by illuminating light at 365 nm and 510 nm. Depending on the photoisomerization, CENP-E activity was regulated not only in vitro but also in cells. We successfully established a novel technique using 5 to dynamically photocontrol the CENP-E-dependent chromosome movement and mitotic progression in a living cell.


Assuntos
Fuso Acromático , Divisão Celular , Metáfase
9.
Front Psychiatry ; 13: 859198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432011

RESUMO

Autism spectrum disorder (ASD) is a heterogeneous disorder characterized by repetitive behaviors and social impairments, often accompanied by learning disabilities. It has been documented that the neuropeptide oxytocin (OXT) ameliorates core symptoms in patients with ASD. We recently reported that chronic administration of intranasal OXT reversed social and learning impairments in prenatally valproic acid (VPA)-exposed rats. However, the underlying molecular mechanisms remain unclear. Here, we explored molecular alterations in the hippocampus of rats and the effects of chronic administration of intranasal OXT (12 µg/kg/d). Microarray analyses revealed that prenatal VPA exposure altered gene expression, a part of which is suggested as a candidate in ASD and is involved in key features including memory, developmental processes, and epilepsy. OXT partly improved the expression of these genes, which were predicted to interact with those involved in social behaviors and hippocampal-dependent memory. Collectively, the present study documented molecular profiling in the hippocampus related to ASD and improvement by chronic treatment with OXT.

10.
Neurosurg Rev ; 45(1): 607-616, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34080079

RESUMO

Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are recommended for high stroke-risk patients with carotid artery stenosis to reduce ischemic events. However, we often face difficulty in determining the best treatment strategy. We aimed to develop an accurate post-CEA/CAS outcome prediction model using machine learning that will serve as a basis for a new decision support tool for patient-specific treatment planning. Retrospectively collected data from 165 consecutive patients with carotid stenosis underwent CEA or CAS and were divided into training and test samples. The following five machine learning algorithms were tuned, and their predictive performance was evaluated by comparison with surgeon predictions: an artificial neural network, logistic regression, support vector machine, random forest, and extreme gradient boosting (XGBoost). Seventeen clinical factors were introduced into the models. Outcome was defined as any ischemic stroke within 30 days after treatment including asymptomatic diffusion-weighted imaging abnormalities. The XGBoost model performed the best in the evaluation; its sensitivity, specificity, positive predictive value, and accuracy were 31.9%, 94.6%, 47.2%, and 86.2%, respectively. These statistical measures were comparable to those of surgeons. Internal carotid artery peak systolic velocity, low-density lipoprotein cholesterol, and procedure (CEA or CAS) were the most contributing factors according to the XGBoost algorithm. We were able to develop a post-procedural outcome prediction model comparable to surgeons in performance. The accurate outcome prediction model will make it possible to make a more appropriate patient-specific selection of CEA or CAS for the treatment of carotid artery stenosis.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Acidente Vascular Cerebral , Cirurgiões , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Humanos , Aprendizado de Máquina , Estudos Retrospectivos , Fatores de Risco , Stents , Resultado do Tratamento
11.
Chem Commun (Camb) ; 57(93): 12500-12503, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34751279

RESUMO

Rho-associated coiled-coil-containing protein kinase (ROCK) is a serine-threonine kinase whose inhibitors are useful for the regulation of the actomyosin system. Here, we developed a photoswitchable ROCK inhibitor based on a phenylazothiazole scaffold. The reversible trans-cis isomerization by visible light stimuli enabled us to manipulate ROCK activities in vitro and in cells.


Assuntos
Luz , Inibidores de Proteínas Quinases/química , Tiazóis/química , Quinases Associadas a rho/antagonistas & inibidores , Células 3T3 , Animais , Isomerismo , Camundongos , Inibidores de Proteínas Quinases/metabolismo , Tiazóis/metabolismo , Quinases Associadas a rho/metabolismo
12.
Org Biomol Chem ; 19(32): 6979-6984, 2021 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-34346473

RESUMO

In the emerging field of photopharmacology, synthetic photoswitches based on reversible photochemical reactions are fused to bioactive molecules. Azobenzene derivatives, which can undergo trans-cis photoisomerization, are typical photoswitches. Most azobenzene-based photochemical tools are active in the thermodynamically stable trans, but not cis, form. cis-Active photochemical tools would be ideal because they can be "initially inactive and active after light illumination" in a reversible mode only by light illumination. However, only a few rational strategies for constructing such "lit-active" photopharmacological tools has been developed. Herein, we report a rationally designed lit-active photoswitchable inhibitor targeting centromere-associated protein E (CENP-E). Using the lit-active inhibitor, we were able to photoregulate CENP-E-dependent mitotic chromosome location in cells. This study provides a framework to facilitate further progress in the development of photopharmacological tools.

13.
FASEB J ; 35(6): e21663, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34042217

RESUMO

cAMP responsive element-binding protein H (CREBH) is a hepatic transcription factor to be activated during fasting. We generated CREBH knock-in flox mice, and then generated liver-specific CREBH transgenic (CREBH L-Tg) mice in an active form. CREBH L-Tg mice showed a delay in growth in the postnatal stage. Plasma growth hormone (GH) levels were significantly increased in CREBH L-Tg mice, but plasma insulin-like growth factor 1 (IGF1) levels were significantly decreased, indicating GH resistance. In addition, CREBH overexpression significantly increased hepatic mRNA and plasma levels of FGF21, which is thought to be as one of the causes of growth delay. However, the additional ablation of FGF21 in CREBH L-Tg mice could not correct GH resistance at all. CREBH L-Tg mice sustained GH receptor (GHR) reduction and the increase of IGF binding protein 1 (IGFBP1) in the liver regardless of FGF21. As GHR is a first step in GH signaling, the reduction of GHR leads to impairment of GH signaling. These data suggest that CREBH negatively regulates growth in the postnatal growth stage via various pathways as an abundant energy response by antagonizing GH signaling.


Assuntos
Composição Corporal , Índice de Massa Corporal , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/fisiologia , Fatores de Crescimento de Fibroblastos/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Hormônio do Crescimento/metabolismo , Fígado/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais
14.
Brain Res ; 1760: 147383, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636166

RESUMO

Accumulation and aggregation of α-synuclein (αSyn) trigger neuronal loss in the substantia nigra pars compacta (SNpc), which in turn causes motor symptoms in Parkinson's disease. We previously demonstrated that fatty acid-binding protein 3 (FABP3), an intracellular fatty acid carrier protein, enhances αSyn neurotoxicity in SNpc and motor impairments after intranigral injection of αSyn fibrils. However, the temporal profile of αSyn fibril spread and their toxicity remains unclear. In the present study, we investigated the temporal profile of αSyn fibril spread and its toxicity, which induces intracellular fibril formation. Monomeric and fibrillar aSyn assemblies were labeled with ATTO550 to distinguish the exogenous form from the endogenous species and injected into bilateral striatum in Fabp3+/+ (wild type) and Fabp3-/- mice. Accumulation of both monomeric and fibrillar exogenous αSyn in the SNpc was drastically decreased in Fabp3-/- mice compared to that in the Fabp3+/+ counterparts. Deletion of Fabp3 also prevented exogenous αSyn fibril-induced seeding of the endogenous αSyn into aggregates containing phosphorylated and filamentous forms in the SNpc. Consistent with these results, loss of dopaminergic neurons and subsequent impaired motor behavior were attenuated in Fabp3-/- mice. These results highlight the crucial role of FABP3 in pathogenic αSyn accumulation and its seeding ability. Taken together, FABP3 could be a potential therapeutic target against αSyn propagation in synucleinopathies.


Assuntos
Proteína 3 Ligante de Ácido Graxo/metabolismo , Parte Compacta da Substância Negra/patologia , Sinucleinopatias/patologia , alfa-Sinucleína/metabolismo , alfa-Sinucleína/toxicidade , Animais , Neurônios Dopaminérgicos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
15.
BMC Neurosci ; 22(1): 9, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33557752

RESUMO

BACKGROUND: We previously reported that heat shock protein 27 (HSP27) phosphorylation plays an important role in the activation of glucose-6-phosphate dehydrogenase (G6PD), resulting in the upregulation of the pentose phosphate pathway and antioxidant effects against cerebral ischemia-reperfusion injury. The present study investigated the effect of geranylgeranylacetone, an inducer of HSP27, on ischemia-reperfusion injury in male rats as a preliminary study to see if further research of the effects of geranylgeranylacetone on the ischemic stroke was warranted. METHODS: In all experiments, male Wistar rats were used. First, we conducted pathway activity profiling based on a gas chromatography-mass spectrometry to identify ischemia-reperfusion-related metabolic pathways. Next, we investigated the effects of geranylgeranylacetone on the pentose phosphate pathway and ischemia-reperfusion injury by real-time polymerase chain reaction (RT-PCR), immunoblotting, and G6PD activity, protein carbonylation and infarct volume analysis. Geranylgeranylacetone or vehicle was injected intracerebroventricularly 3 h prior to middle cerebral artery occlusion or sham operation. RESULTS: Pathway activity profiling demonstrated that changes in the metabolic state depended on reperfusion time and that the pentose phosphate pathway and taurine-hypotaurine metabolism pathway were the most strongly related to reperfusion among 137 metabolic pathways. RT-PCR demonstrated that geranylgeranylacetone did not significantly affect the increase in HSP27 transcript levels after ischemia-reperfusion. Immunoblotting showed that geranylgeranylacetone did not significantly affect the elevation of HSP27 protein levels. However, geranylgeranylacetone significantly increase the elevation of phosphorylation of HSP27 after ischemia-reperfusion. In addition, geranylgeranylacetone significantly affected the increase in G6PD activity, and reduced the increase in protein carbonylation after ischemia-reperfusion. Accordingly, geranylgeranylacetone significantly reduced the infarct size (median 31.3% vs 19.9%, p = 0.0013). CONCLUSIONS: As a preliminary study, these findings suggest that geranylgeranylacetone may be a promising agent for the treatment of ischemic stroke and would be worthy of further study. Further studies are required to clearly delineate the mechanism of geranylgeranylacetone-induced HSP27 phosphorylation in antioxidant effects, which may guide the development of new approaches for minimizing the impact of cerebral ischemia-reperfusion injury.


Assuntos
Isquemia Encefálica/patologia , Diterpenos/farmacologia , Proteínas de Choque Térmico HSP27/metabolismo , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/patologia , Animais , Isquemia Encefálica/metabolismo , Proteínas de Choque Térmico HSP27/efeitos dos fármacos , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo
16.
Acta Physiol (Oxf) ; 232(1): e13613, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33393208

RESUMO

AIMS: Adult hippocampal neurogenesis plays an important role in neuronal plasticity and maintenance in mammals. Low-threshold voltage-gated T-type calcium channels produce calcium spikes that increase fast action potentials in newborn cells in the hippocampal dentate gyrus (DG); however, their role in adult hippocampal neurogenesis remains unclear. Here, we demonstrate impaired adult hippocampal neurogenesis in Cav3.1T-type calcium channel knockout mice. METHODS AND RESULTS: Cav3.1T-type calcium channel was predominantly localized in neuronal progenitor cells of the mouse hippocampal DG. By counting the number of 5-bromo-2'-deoxyuridine-labeled cells, decreased proliferation and survival of newly generated cells were observed in the adult hippocampal DG in Cav3.1 knockout mice as compared to wild-type (WT) mice. Moreover, the degree of maturation of doublecortin-positive cells in Cav3.1 knockout mice was lower than that in WT mice, suggesting that Cav3.1 deletion may impair neuronal differentiation. Consistent with impaired hippocampal neurogenesis, Cav3.1 knockout mice showed decreased social interaction. Reduced phosphorylation levels of calcium/calmodulin-dependent protein kinase II and protein kinase B were closely associated with impaired hippocampal neurogenesis in Cav3.1 knockout mice. Moreover, the mRNA and protein expression levels of brain-derived neurotrophic factor, important for neurogenesis, were significantly decreased in Cav3.1 knockout mice. Finally, gene ontology analysis revealed alterations in genes related to the promotion of cell death/apoptosis and suppression of cell proliferation/neuronal differentiation pathways, including Bdnf. CONCLUSION: These results suggest that the Cav3.1T-type calcium channel may be a key molecule required for cell proliferation, survival and neuronal differentiation in newly generated cells of the adult mouse hippocampus.


Assuntos
Canais de Cálcio Tipo T , Animais , Canais de Cálcio Tipo T/metabolismo , Proliferação de Células , Sobrevivência Celular , Giro Denteado , Hipocampo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurogênese , Neurônios/metabolismo
17.
Int J Mol Sci ; 22(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401521

RESUMO

In synucleinopathies, while motor symptoms are thought to be attributed to the accumulation of misfolded α-synuclein (αSyn) in nigral dopaminergic neurons, it remains to be elucidated how cognitive decline arises. Here, we investigated the effects of distinct αSyn strains on cognition and the related neuropathology in the medial septum/diagonal band (MS/DB), a key region for cognitive processing. Bilateral injection of αSyn fibrils into the dorsal striatum potently impaired cognition in mice. The cognitive decline was accompanied by accumulation of phosphorylated αSyn at Ser129 and reduction of gamma-aminobutyric acid (GABA)-ergic but not cholinergic neurons in the MS/DB. Since we have demonstrated that fatty acid-binding protein 3 (FABP3) is critical for αSyn neurotoxicity in nigral dopaminergic neurons, we investigated whether FABP3 also participates in αSyn pathology in the MS/DB and cognitive decline. FABP3 was highly expressed in GABAergic but rarely in cholinergic neurons in the MS/DB. Notably, Fabp3 deletion antagonized the accumulation of phosphorylated αSyn, decrease in GABAergic neurons, and cognitive impairment caused by αSyn fibrils. Overall, the present study indicates that FABP3 mediates αSyn neurotoxicity in septal GABAergic neurons and the resultant cognitive impairment, and that FABP3 in this subpopulation could be a therapeutic target for dementia in synucleinopathies.


Assuntos
Disfunção Cognitiva/etiologia , Proteína 3 Ligante de Ácido Graxo/metabolismo , Neurônios GABAérgicos/metabolismo , Neuroproteção , Sinucleinopatias/complicações , Animais , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/prevenção & controle , Proteína 3 Ligante de Ácido Graxo/fisiologia , Neurônios GABAérgicos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sinucleinopatias/fisiopatologia , alfa-Sinucleína
18.
Ann Vasc Surg ; 68: 571.e15-571.e20, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32422292

RESUMO

It is essential to establish cardiopulmonary bypass by percutaneous insertion of a large-bore catheter via both the femoral vein and internal jugular vein (IJV) for minimally invasive cardiac surgery (MICS). Complications associated with IJV catheterization during MICS have been reported in the literature; however, vascular injury of the subclavian artery (SCA) is rare. We herein present a rare case in which an iatrogenic arteriovenous fistula (AVF) between the right SCA and IJV after MICS was successfully treated by endovascular coil embolization. A 61-year-old man who had undergone mitral valve repair by MICS 10 months before presentation was referred because of pulsatile cervical bruit and tinnitus. Radiographic examination revealed a right SCA pseudoaneurysm associated with an AVF located between the right common carotid artery and vertebral artery. The AVF was completely occluded with detachable coils using a double-catheter technique to avoid coil migration into the IJV. This technique has been used to treat high-flow or complex AVFs, including pulmonary and renal AVFs. As shown in the present case, it is also useful to treat an iatrogenic AVF between the SCA and IJV.


Assuntos
Falso Aneurisma/terapia , Fístula Arteriovenosa/terapia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Embolização Terapêutica/instrumentação , Doença Iatrogênica , Veias Jugulares/lesões , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Artéria Subclávia/lesões , Lesões do Sistema Vascular/terapia , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/etiologia , Fístula Arteriovenosa/diagnóstico por imagem , Fístula Arteriovenosa/etiologia , Humanos , Veias Jugulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/cirurgia , Artéria Subclávia/diagnóstico por imagem , Resultado do Tratamento , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia
19.
Radiol Case Rep ; 15(5): 542-544, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32180857

RESUMO

We describe a unique technique to reduce the amount of contrast medium by injecting diluted contrast medium from the microcatheter during neurointervention. A patient with severe renal impairment due to polycystic kidney was referred for endovascular surgery for wide-neck middle cerebral artery aneurysm. In order to reduce the amount of contrast medium, contrast medium was injected from the microcatheter placed in the middle cerebral artery during coil embolization; renal function decline was not observed after the procedure. This technique, therefore, reduces the amount of contrast medium and enables one to perform coil embolization safely.

20.
Brain Tumor Pathol ; 37(2): 76-80, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32215804

RESUMO

Intracranial myxoid mesenchymal tumors harboring EWSR1 fusions with CREB transcriptional factor gene families were recently described in several case reports and a few case series and this tumor closely resembles the myxoid variant of angiomatoid fibrous histiocytoma. We herein present an intracranial mesenchymal myxoid tumor arising in the third ventricle of a middle-aged woman. The tumor displayed prominent myxoid features consisting of mildly atypical oval to round cells, arranged in reticular and cord-like structures, with starburst-like amianthoid fibers, whereas it lacked pseudoangiomatoid spaces, pseudocapsules and lymphoid cuffing. Immunophenotypically, tumor cells were positive for EMA, desmin, and ALK (focal). EWSR1 and CREB1 rearrangements were identified using FISH assay. The proliferation index was low. It is currently uncertain whether these myxoid tumors represent a variant of angiomatoid fibrous histiocytoma or a novel tumor entity.


Assuntos
Neoplasias Encefálicas/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Fusão Gênica , Histiocitoma Fibroso Maligno/genética , Proteína EWS de Ligação a RNA/genética , Neoplasias Encefálicas/patologia , Feminino , Rearranjo Gênico , Histiocitoma Fibroso Maligno/patologia , Humanos , Pessoa de Meia-Idade
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