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1.
Nature ; 628(8009): 818-825, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38658687

RESUMO

Timothy syndrome (TS) is a severe, multisystem disorder characterized by autism, epilepsy, long-QT syndrome and other neuropsychiatric conditions1. TS type 1 (TS1) is caused by a gain-of-function variant in the alternatively spliced and developmentally enriched CACNA1C exon 8A, as opposed to its counterpart exon 8. We previously uncovered several phenotypes in neurons derived from patients with TS1, including delayed channel inactivation, prolonged depolarization-induced calcium rise, impaired interneuron migration, activity-dependent dendrite retraction and an unanticipated persistent expression of exon 8A2-6. We reasoned that switching CACNA1C exon utilization from 8A to 8 would represent a potential therapeutic strategy. Here we developed antisense oligonucleotides (ASOs) to effectively decrease the inclusion of exon 8A in human cells both in vitro and, following transplantation, in vivo. We discovered that the ASO-mediated switch from exon 8A to 8 robustly rescued defects in patient-derived cortical organoids and migration in forebrain assembloids. Leveraging a transplantation platform previously developed7, we found that a single intrathecal ASO administration rescued calcium changes and in vivo dendrite retraction of patient neurons, suggesting that suppression of CACNA1C exon 8A expression is a potential treatment for TS1. Broadly, these experiments illustrate how a multilevel, in vivo and in vitro stem cell model-based approach can identify strategies to reverse disease-relevant neural pathophysiology.


Assuntos
Transtorno Autístico , Síndrome do QT Longo , Oligonucleotídeos Antissenso , Sindactilia , Animais , Feminino , Humanos , Masculino , Camundongos , Processamento Alternativo/efeitos dos fármacos , Processamento Alternativo/genética , Transtorno Autístico/tratamento farmacológico , Transtorno Autístico/genética , Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Canais de Cálcio Tipo L/genética , Movimento Celular/efeitos dos fármacos , Dendritos/metabolismo , Éxons/genética , Síndrome do QT Longo/tratamento farmacológico , Síndrome do QT Longo/genética , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Oligonucleotídeos Antissenso/uso terapêutico , Organoides/efeitos dos fármacos , Organoides/metabolismo , Prosencéfalo/metabolismo , Prosencéfalo/citologia , Sindactilia/tratamento farmacológico , Sindactilia/genética , Interneurônios/citologia , Interneurônios/efeitos dos fármacos
2.
Nature ; 610(7931): 319-326, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36224417

RESUMO

Self-organizing neural organoids represent a promising in vitro platform with which to model human development and disease1-5. However, organoids lack the connectivity that exists in vivo, which limits maturation and makes integration with other circuits that control behaviour impossible. Here we show that human stem cell-derived cortical organoids transplanted into the somatosensory cortex of newborn athymic rats develop mature cell types that integrate into sensory and motivation-related circuits. MRI reveals post-transplantation organoid growth across multiple stem cell lines and animals, whereas single-nucleus profiling shows progression of corticogenesis and the emergence of activity-dependent transcriptional programs. Indeed, transplanted cortical neurons display more complex morphological, synaptic and intrinsic membrane properties than their in vitro counterparts, which enables the discovery of defects in neurons derived from individuals with Timothy syndrome. Anatomical and functional tracings show that transplanted organoids receive thalamocortical and corticocortical inputs, and in vivo recordings of neural activity demonstrate that these inputs can produce sensory responses in human cells. Finally, cortical organoids extend axons throughout the rat brain and their optogenetic activation can drive reward-seeking behaviour. Thus, transplanted human cortical neurons mature and engage host circuits that control behaviour. We anticipate that this approach will be useful for detecting circuit-level phenotypes in patient-derived cells that cannot otherwise be uncovered.


Assuntos
Vias Neurais , Organoides , Animais , Animais Recém-Nascidos , Transtorno Autístico , Humanos , Síndrome do QT Longo , Motivação , Neurônios/fisiologia , Optogenética , Organoides/citologia , Organoides/inervação , Organoides/transplante , Ratos , Recompensa , Córtex Somatossensorial/citologia , Córtex Somatossensorial/fisiologia , Células-Tronco/citologia , Sindactilia
3.
Eur J Neurosci ; 58(11): 4298-4309, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37968729

RESUMO

The effects of the Eurycoma longifolia (also known as Tongkat Ali [TA]) on sleep and wakefulness was evaluated in C57BL/6 mice. While TA has been used as an aphrodisiac in males, it exhibits various pharmacological effects. The most notable effect observed with TA was wake-enhancement during the second half of the active period, accompanied by significant elevations in core body temperature (CBT). In contrast, sleep was enhanced during the resting period (i.e., increase in rapid eye movement [REM] sleep and delta electroencephalography [EEG] power in non-REM sleep) with significant declines in CBT. The transition of TA's effects between resting and active periods was rapid. The results of the experiments in constant darkness indicate that TA prolongs the circadian tau and that this transition is governed by circadian clock mechanisms rather than light exposure. TA did not demonstrate efficacy in aiding sleep in an acute stress-induced insomnia model; thus, TA may be more suitable as a wake-enhancing agent for daytime sleepiness, as sleep propensity tends to accumulate towards the end of active period. Since TA amplifies the rest-activity pattern, prolongs circadian tau and increases REM sleep, thereby reversing some common symptoms seen in elderly subjects, it may also hold promise as a rejuvenating medicine.


Assuntos
Eurycoma , Humanos , Masculino , Camundongos , Animais , Idoso , Vigília , Camundongos Endogâmicos C57BL , Sono , Sono REM , Eletroencefalografia , Ritmo Circadiano
4.
Proc Natl Acad Sci U S A ; 113(11): E1536-44, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26903630

RESUMO

In humans, the connection between sleep and mood has long been recognized, although direct molecular evidence is lacking. We identified two rare variants in the circadian clock gene PERIOD3 (PER3-P415A/H417R) in humans with familial advanced sleep phase accompanied by higher Beck Depression Inventory and seasonality scores. hPER3-P415A/H417R transgenic mice showed an altered circadian period under constant light and exhibited phase shifts of the sleep-wake cycle in a short light period (photoperiod) paradigm. Molecular characterization revealed that the rare variants destabilized PER3 and failed to stabilize PERIOD1/2 proteins, which play critical roles in circadian timing. Although hPER3-P415A/H417R-Tg mice showed a mild depression-like phenotype, Per3 knockout mice demonstrated consistent depression-like behavior, particularly when studied under a short photoperiod, supporting a possible role for PER3 in mood regulation. These findings suggest that PER3 may be a nexus for sleep and mood regulation while fine-tuning these processes to adapt to seasonal changes.


Assuntos
Afeto/fisiologia , Proteínas Circadianas Period/genética , Transtorno Afetivo Sazonal/genética , Idoso , Sequência de Aminoácidos , Animais , Relógios Circadianos/genética , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteínas Circadianas Period/metabolismo , Fotoperíodo , Estabilidade Proteica , Transtornos do Sono do Ritmo Circadiano/genética
5.
Ann Neurol ; 74(6): 786-93, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23821583

RESUMO

OBJECTIVE: To determine whether histamine cells are altered in human narcolepsy with cataplexy and in animal models of this disease. METHODS: Immunohistochemistry for histidine decarboxylase (HDC) and quantitative microscopy were used to detect histamine cells in human narcoleptics, hypocretin (Hcrt) receptor-2 mutant dogs, and 3 mouse narcolepsy models: Hcrt (orexin) knockouts, ataxin-3-orexin, and doxycycline-controlled-diphtheria-toxin-A-orexin. RESULTS: We found an average 64% increase in the number of histamine neurons in human narcolepsy with cataplexy, with no overlap between narcoleptics and controls. However, we did not see altered numbers of HDC cells in any of the animal models of narcolepsy. INTERPRETATION: Changes in histamine cell numbers are not required for the major symptoms of narcolepsy, because all animal models have these symptoms. The histamine cell changes we saw in humans did not occur in the 4 animal models of Hcrt dysfunction we examined. Therefore, the loss of Hcrt receptor-2, of the Hcrt peptide, or of Hcrt cells is not sufficient to produce these changes. We speculate that the increased histamine cell numbers we see in human narcolepsy may instead be related to the process causing the human disorder. Although research has focused on possible antigens within the Hcrt cells that might trigger their autoimmune destruction, the present findings suggest that the triggering events of human narcolepsy may involve a proliferation of histamine-containing cells. We discuss this and other explanations of the difference between human narcoleptics and animal models of narcolepsy, including therapeutic drug use and species differences.


Assuntos
Encéfalo/metabolismo , Cataplexia/metabolismo , Histamina/metabolismo , Narcolepsia/metabolismo , Neurônios/metabolismo , Adulto , Idoso de 80 Anos ou mais , Animais , Encéfalo/citologia , Encéfalo/patologia , Contagem de Células/métodos , Modelos Animais de Doenças , Cães , Feminino , Humanos , Masculino , Camundongos/genética , Camundongos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Mutação/genética
6.
Neurotherapeutics ; 20(2): 546-563, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36544071

RESUMO

Wake-promoting agents are used for the management of excessive daytime sleepiness caused by narcolepsy. Clinical and preclinical data suggests that solriamfetol, a novel dopamine and norepinephrine reuptake inhibitor, is a promising therapeutic option for excessive daytime sleepiness. We provide the first head-to-head comparison of in vivo efficacy between modafinil and solriamfetol in narcoleptic mice. Both compounds induced potent wake-promoting effects in littermate wild-type and orexin-tTA; TetO-DTA mice when dosed at active and resting phases. However, neither modafinil nor solriamfetol alleviated cataplexy. Remarkably, modafinil significantly induced locomotor activity but solriamfetol had small effects. Awake electroencephalogram profiles revealed that modafinil augmented theta oscillation in a dose-dependent manner, but, on the contrary, the response to solriamfetol was blunted, reflecting the differences in their neurochemical properties and anxiogenic effects. Drug-induced anxiety-related behaviors were evaluated at equipotent wake-promoting doses in WT and DTA mice using the elevated plus maze and forced swim tests. Importantly, 100 mg/kg of modafinil significantly produced anxiety-related behaviors in WT mice, whereas 150 mg/kg of solriamfetol did not have anxiogenic effects. On the other hand, DTA mice exhibited trait anxiety and altered drug responses. Our results suggest that solriamfetol potently promotes wakefulness without psychomotor effects and without inducing anxiety-related behaviors.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Narcolepsia , Camundongos , Animais , Modafinila/uso terapêutico , Narcolepsia/tratamento farmacológico , Distúrbios do Sono por Sonolência Excessiva/tratamento farmacológico , Nível de Alerta , Ansiedade/tratamento farmacológico
7.
Neuron ; 111(22): 3604-3618.e11, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657440

RESUMO

Myelination depends on the maintenance of oligodendrocytes that arise from oligodendrocyte precursor cells (OPCs). We show that OPC-specific proliferation, morphology, and BMAL1 are time-of-day dependent. Knockout of Bmal1 in mouse OPCs during development disrupts the expression of genes associated with circadian rhythms, proliferation, density, morphology, and migration, leading to changes in OPC dynamics in a spatiotemporal manner. Furthermore, these deficits translate into thinner myelin, dysregulated cognitive and motor functions, and sleep fragmentation. OPC-specific Bmal1 loss in adulthood does not alter OPC density at baseline but impairs the remyelination of a demyelinated lesion driven by changes in OPC morphology and migration. Lastly, we show that sleep fragmentation is associated with increased prevalence of the demyelinating disorder multiple sclerosis (MS), suggesting a link between MS and sleep that requires further investigation. These findings have broad mechanistic and therapeutic implications for brain disorders that include both myelin and sleep phenotypes.


Assuntos
Fatores de Transcrição ARNTL , Esclerose Múltipla , Camundongos , Animais , Fatores de Transcrição ARNTL/genética , Privação do Sono/metabolismo , Camundongos Knockout , Oligodendroglia/metabolismo , Bainha de Mielina/metabolismo , Esclerose Múltipla/metabolismo , Sono/genética , Diferenciação Celular
8.
Curr Top Behav Neurosci ; 59: 427-446, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711025

RESUMO

The function of mast cells in the brain for the mediation of neurobehavior is largely unknown. Mast cells are a heterogeneous population of granulocytic cells in the immune system. Mast cells contain numerous mediators, such as histamine, serotonin, cytokines, chemokines, and lipid-derived factors. Mast cells localize not only in the periphery but are also resident in the brain of mammalians. Mast cells in the brain are constitutively active, releasing their contents gradually or rapidly by anaphylactic degranulation. Their activity is also increased by a wide range of stimuli including both immune and non-immune signals. Brain mast cell neuromodulation may thus be involved in various neurobehavior in health and diseases.Using Kit mutant mast cell deficient mice (KitW/KitW-v), we obtained results indicating that brain mast cells regulate sleep/wake and other behavioral phenotypes and that histamine from brain mast cells promotes wakefulness. These findings were also confirmed using a newer inducible and Kit-independent mast cell deficient Mas-TRECK (toxin receptor knockout) mouse. Injections of diphtheria toxin (DT) selectively deplete mast cells and reduce wakefulness during the periods of mast cell depletion.We recently introduced a mouse model for chronic sleep loss associated with diabetes. The mice reared on the wire net for 3 weeks (i.e., mild stress [MS]) showed decreased amount of non-rapid eye movement (NREM) sleep, increased sleep fragmentation, and abnormal glucose tolerance test [GTT] and insulin tolerance test [ITT], phenotypes which mirror human chronic insomnia. Interestingly, these mice with insomnia showed an increased number of mast cells in both the brain and adipose tissue. Mast cell deficient mice (KitW/KitW-v) and inhibition of mast cell functions with cromolyn or a histamine H1 receptor antagonist administration ameliorated both insomnia and abnormal glycometabolism. Mast cells may therefore represent an important pathophysiological mediator in sleep impairments and abnormal glycometabolism associated with chronic insomnia.


Assuntos
Insulinas , Distúrbios do Início e da Manutenção do Sono , Animais , Encéfalo , Cromolina Sódica , Citocinas , Toxina Diftérica , Histamina , Antagonistas dos Receptores Histamínicos H1/farmacologia , Humanos , Lipídeos , Mamíferos , Mastócitos/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Serotonina , Sono/fisiologia
9.
NPJ Genom Med ; 7(1): 29, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414074

RESUMO

Idiopathic hypersomnia (IH) is a rare, heterogeneous sleep disorder characterized by excessive daytime sleepiness. In contrast to narcolepsy type 1, which is a well-defined type of central disorders of hypersomnolence, the etiology of IH is poorly understood. No susceptibility loci associated with IH have been clearly identified, despite the tendency for familial aggregation of IH. We performed a variation screening of the prepro-orexin/hypocretin and orexin receptors genes and an association study for IH in a Japanese population, with replication (598 patients and 9826 controls). We identified a rare missense variant (g.42184347T>C; p.Lys68Arg; rs537376938) in the cleavage site of prepro-orexin that was associated with IH (minor allele frequency of 1.67% in cases versus 0.32% in controls, P = 2.7 × 10-8, odds ratio = 5.36). Two forms of orexin (orexin-A and -B) are generated from cleavage of one precursor peptide, prepro-orexin. The difference in cleavage efficiency between wild-type (Gly-Lys-Arg; GKR) and mutant (Gly-Arg-Arg; GRR) peptides was examined by assays using proprotein convertase subtilisin/kexin (PCSK) type 1 and PCSK type 2. In both PCSK1 and PCSK2 assays, the cleavage efficiency of the mutant peptide was lower than that of the wild-type peptide. We also confirmed that the prepro-orexin peptides themselves transmitted less signaling through orexin receptors than mature orexin-A and orexin-B peptides. These results indicate that a subgroup of IH is associated with decreased orexin signaling, which is believed to be a hallmark of narcolepsy type 1.

10.
Sci Rep ; 11(1): 20816, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34675261

RESUMO

Sleep deprivation induces adverse effects on the health, productivity, and performance. The individuals who could not get enough sleep temporarily experience the symptoms of an induced acute insomnia. This study investigated the efficacy of sake yeast in treatment of acute insomnia in mice. The results of this study showed that sake yeast induced a significant dose-dependent wake reduction, a rapid eye movement (REM) and a non-REM (NREM) sleep enhancement during the first 6 h after the oral administration of sake yeast with locomotor activity and core body temperature decreases under the stressful environment in a new cage. In fact, the wake amounts at 3 h and 6 h were significantly reduced after the oral administration of sake yeast compared with the vehicle. The NREM sleep amounts at 3 h and 6 h significantly increased after the administration of sake yeast compared with the vehicle. The REM amount at 6 h significantly increased after the administration of sake yeast compared with the vehicle, but not at 3 h. The previous study suggested that the sleep-promoting effects of sake yeast could be referred from the activating effect of adenosine A2A receptor (A2AR). In summary, the sake yeast is an A2AR agonist and may induce sleep due to its stress-reducing and anti-anxiety properties. Further verification of the involvement of adenosine in the pathophysiology of insomnia is needed.


Assuntos
Saccharomyces cerevisiae , Distúrbios do Início e da Manutenção do Sono/terapia , Fermento Seco/uso terapêutico , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Saccharomyces cerevisiae/metabolismo , Sono , Sono REM , Vigília , Fermento Seco/metabolismo
11.
Physiol Rep ; 9(20): e15072, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34676689

RESUMO

OBJECTIVE: Although both obesity and body posture are important factors affecting end-expiratory lung volume (EELV) and upper airway patency, the influence of those factors on EELV and the association between EELV and upper airway calibers are still unknown in mice. This study examined such interaction effects in obese mice to test the hypothesis that obese mice have decreased EELV accompanied by structural alterations of the upper airway. METHODS: A high-resolution in vivo micro-computed tomography was utilized to scan anesthetized lean and diet-induced obese mice in the prone and supine positions, followed by quantifying lung volume and analyzing upper airway morphology. RESULTS: There was a statistically significant interaction between the effects of body weight and posture on both EELV (p = 0.0049, η 2  = 0.1041) and upper airway calibers (p = 0.0215, η 2  = 0.6304). In lean mice, EELV in the prone position was significantly larger than in the supine position (prone EELV = 193.22 ± 9.10 µl vs. supine EELV = 176.01 ± 10.91 µl; p = 0.0072), whereas obese mice did not have such an improvement in EELV in the prone position (prone EELV = 174.37 ± 20.23 µl vs. supine EELV = 183.39 ± 17.49 µl; p = 0.0981) and tended to have a smaller upper airway when EELV was low based on Spearman's correlation analysis. CONCLUSIONS: These data indicate that obesity is an important factor compromising both EELV and upper airway calibers in a posture-dependent manner even in mice, which should be taken into consideration in future studies regarding upper airway collapse and lung mechanical properties using mice.


Assuntos
Dieta , Pulmão/fisiopatologia , Obesidade/fisiopatologia , Postura , Respiração , Magreza/fisiopatologia , Animais , Peso Corporal , Medidas de Volume Pulmonar , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/etiologia , Mecânica Respiratória
12.
Behav Brain Res ; 403: 113143, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33516739

RESUMO

Mast cells (MCs) exist intracranially and have been reported to affect higher brain functions in rodents. However, the role of MCs in the regulation of emotionality and social behavior is unclear. In the present study, using male mice, we examined the relationship between MCs and social behavior and investigated the underlying mechanisms. Wild-type male mice intraventricularly injected with a degranulator of MCs exhibited a marked increase in a three-chamber sociability test. In addition, removal of MCs in Mast cell-specific Toxin Receptor-mediated Conditional cell Knock out (Mas-TRECK) male mice showed reduced social preference levels in a three-chamber sociability test without other behavioral changes, such as anxiety-like and depression-like behavior. Mas-TRECK male mice also had reduced serotonin content and serotonin receptor expression and increased oxytocin receptor expression in the brain. These results suggested that MCs may contribute to the regulation of social behavior in male mice. This effect may be partially mediated by serotonin derived from MCs in the brain.


Assuntos
Comportamento Animal/fisiologia , Encéfalo , Mastócitos/fisiologia , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Comportamento Social , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Masculino , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , p-Metoxi-N-metilfenetilamina/farmacologia
13.
J Vet Med Sci ; 72(1): 7-11, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19893285

RESUMO

Previously, we have reported drastic strain differences of diazepam metabolism in the livers of a variety of rat strain. In this study, to characterize strain and sex differences of diazepam metabolism in the kidney, renal microsomal diazepam metabolic activities were determined in the Dark Agouti (DA), Sprague-Dawley (SD), Brown Norway (BN) and Wistar (WS) strains of rat. We found that the major pathway of diazepam metabolism in the kidney was diazepam N-demethylation, which is different from that in the liver, 3-hydroxylation. A Dose-course (12.5-200 muM of diazepam) study revealed that the DA and WS male rats had higher diazepam N-demethylation activity than the SD and BN rats. In contrast to the males, a lower activity of diazepam N-demethylation was observed in female BN rats. By Western blot analysis, constitutive protein expressions of cytochrome P450 (CYP) 2C11, which is responsible for diazepam N-demethylation, were detected in the 4 strain in both the male and female rats, and the BN rats had lower expression levels of CYP2C11 protein. However, we did not observe significant differences in the kinetic parameters of diazepam N-demethylation. Our results suggested that there was a strain difference in CYP-dependent diazepam N-demethylation in the rat kidney, which is different from the finding in liver microsomes.


Assuntos
Ansiolíticos/farmacocinética , Diazepam/farmacocinética , Rim/metabolismo , Animais , Ansiolíticos/química , Ansiolíticos/metabolismo , Hidrocarboneto de Aril Hidroxilases/genética , Hidrocarboneto de Aril Hidroxilases/metabolismo , Família 2 do Citocromo P450 , Diazepam/química , Diazepam/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Masculino , Microssomos/metabolismo , Estrutura Molecular , Ratos , Ratos Endogâmicos , Caracteres Sexuais , Esteroide 16-alfa-Hidroxilase/genética , Esteroide 16-alfa-Hidroxilase/metabolismo
14.
Neurosci Lett ; 722: 134832, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32050100

RESUMO

The terpene lactones of Ginkgo biloba extract, namely ginkgolides (A, B, and C) and bilobalide, possess antioxidant, anti-inflammatory, and neuroprotective effects. They are widely prescribed for the treatment of cerebral dysfunctions and neurological impairments. In addition, they demonstrate antagonistic action at the gamma-aminobutyric acid type A and glycine receptors, which are members of the ligand-gated ion channel superfamily. In the present study, the effects of ginkgolides (A, B, and C) and bilobalide on sleep in C57BL/6 mice were investigated. Ginkgolide B was found to dose-dependently increase the amount of wake and decrease that of non-rapid eye movement sleep without changes in the electroencephalography power density of each sleep/wake stage, core body temperature and locomotor activity for the first 6 h after intraperitoneal injection. Of note, the amount of wake after injection of 5 mg/kg of ginkgolide B showed a significant increase (14.9 %) compared with that of vehicle (P = 0.005). In contrast, there were no significant differences in the amount of sleep, core body temperature, and locomotor activity in the mice injected with ginkgolide A and C. Bilobalide briefly induced a decrease in locomotor activity but did not exert significant effects on the amounts of sleep and wake. The modes of action of the wake-enhancing effects of ginkgolide B are unknown. However, it may act through the antagonism of gamma-aminobutyric acid type A and glycine receptors because it is established that these inhibitory amino acids mediate sleep and sleep-related physiology. It is of interest to further evaluate the stimulant and awaking actions of ginkgolide B on the central nervous system in clinical and basic research studies.


Assuntos
Ginkgo biloba , Ginkgolídeos/administração & dosagem , Lactonas/administração & dosagem , Extratos Vegetais/administração & dosagem , Fases do Sono/efeitos dos fármacos , Vigília/efeitos dos fármacos , Animais , Ciclopentanos/administração & dosagem , Relação Dose-Resposta a Droga , Eletroencefalografia/efeitos dos fármacos , Furanos/administração & dosagem , Injeções Intraperitoneais/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fases do Sono/fisiologia , Vigília/fisiologia
15.
Sci Rep ; 10(1): 21323, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33288820

RESUMO

A high prevalence of obstructive sleep apnea (OSA) has been reported in Down syndrome (DS) owing to the coexistence of multiple predisposing factors related to its genetic abnormality, posing a challenge for the management of OSA. We hypothesized that DS mice recapitulate craniofacial abnormalities and upper airway obstruction of human DS and can serve as an experimental platform for OSA research. This study, thus, aimed to quantitatively characterize the upper airway as well as craniofacial abnormalities in Dp(16)1Yey (Dp16) mice. Dp16 mice demonstrated craniofacial hypoplasia, especially in the ventral part of the skull and the mandible, and rostrally positioned hyoid. These changes were accompanied with a shorter length and smaller cross-sectional area of the upper airway, resulting in a significantly reduced upper airway volume in Dp16 mice. Our non-invasive approach, a combination of computational fluid dynamics and high-resolution micro-CT imaging, revealed a higher negative pressure inside the airway of Dp16 mice compared to wild-type littermates, showing the potential risk of upper airway collapse. Our study indicated that Dp16 mice can be a useful model to examine the pathophysiology of increased upper airway collapsibility of DS and to evaluate the efficacy of therapeutic interventions for breathing and sleep anomalies.


Assuntos
Síndrome de Down/diagnóstico por imagem , Apneia Obstrutiva do Sono/diagnóstico por imagem , Animais , Anormalidades Craniofaciais/diagnóstico por imagem , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Pletismografia , Tomografia por Raios X/métodos
16.
Nat Med ; 26(12): 1888-1898, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32989314

RESUMO

22q11.2 deletion syndrome (22q11DS) is a highly penetrant and common genetic cause of neuropsychiatric disease. Here we generated induced pluripotent stem cells from 15 individuals with 22q11DS and 15 control individuals and differentiated them into three-dimensional (3D) cerebral cortical organoids. Transcriptional profiling across 100 days showed high reliability of differentiation and revealed changes in neuronal excitability-related genes. Using electrophysiology and live imaging, we identified defects in spontaneous neuronal activity and calcium signaling in both organoid- and 2D-derived cortical neurons. The calcium deficit was related to resting membrane potential changes that led to abnormal inactivation of voltage-gated calcium channels. Heterozygous loss of DGCR8 recapitulated the excitability and calcium phenotypes and its overexpression rescued these defects. Moreover, the 22q11DS calcium abnormality could also be restored by application of antipsychotics. Taken together, our study illustrates how stem cell derived models can be used to uncover and rescue cellular phenotypes associated with genetic forms of neuropsychiatric disease.


Assuntos
Sinalização do Cálcio/genética , Córtex Cerebral/ultraestrutura , Síndrome de DiGeorge/diagnóstico , Neurônios/ultraestrutura , Adulto , Diferenciação Celular/genética , Córtex Cerebral/patologia , Síndrome de DiGeorge/patologia , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/ultraestrutura , Masculino , Neurônios/patologia , Organoides/patologia , Organoides/ultraestrutura , Adulto Jovem
17.
Drug Metab Dispos ; 37(8): 1703-10, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19420131

RESUMO

Cytochrome P450 (P450) 2D2 (CYP2D2) enzyme is known to metabolize the majority of typical substrates of the human CYP2D6 enzyme, which is the most extensively characterized polymorphic drug-metabolizing enzyme. Despite its impact on drug metabolism in rats, the transcriptional regulation of CYP2D2 remains to be elucidated. We clarified the molecular mechanism of CYP2D2 gene expression. The CYP2D2 gene was positively regulated by the poly(C)-binding protein heterogeneous nuclear ribonucleoprotein K (hnRNP K) through a transcriptional regulatory element located in the 5'-flanking region from -94 to -113. To date, nothing is known about the potential role of hnRNP K in P450 gene regulation. Thus, this is the first report that hnRNP K protein is involved in CYP2D2 gene regulation. Furthermore, we elucidated the genetic basis of the extremely low expression of CYP2D2 mRNA in Dark Agouti (DA) rats. Because of its relatively low abundance, DA rats have been frequently used for the study of CYP2D substrate metabolism as the animal model of the poor metabolizer phenotype for CYP2D6 compared with Sprague-Dawley rats as an extensive metabolizer phenotype. We found a single substitution within the transcriptional regulatory element of the CYP2D2 gene in DA rats. The mutation was detected in the polypyrimidine sequence that is the preferred binding site for hnRNP K protein. The mutation within the transcriptional regulatory element attenuated the binding of hnRNP K protein. In conclusion, decreased recruitment of hnRNP K protein to the mutated sequence causes the low expression of CYP2D2 mRNA in DA rats.


Assuntos
Região 5'-Flanqueadora , Citocromo P-450 CYP2D6/genética , Regulação Enzimológica da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Fígado/enzimologia , Polimorfismo de Nucleotídeo Único , Transcrição Gênica , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Citocromo P-450 CYP2D6/metabolismo , Análise Mutacional de DNA , Feminino , Genes Reporter , Genótipo , Masculino , Fenótipo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transfecção
18.
Drug Metab Dispos ; 37(2): 268-71, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18971314

RESUMO

Diazepam (7-chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1,4-benzodiazepin-2-one) is widely used as a sedative, hypnotic, and anti-anxiety drug. At low diazepam concentrations, p-hydroxylation is the major metabolic pathway in rat liver microsomes. However, there are marked ( approximately 300-fold) inter- and intrastrain differences in the activity among Sprague-Dawley, Brown Norway, Dark Agouti, and Wistar rats. In our previous study, we determined that a deficiency of CYP2D3 protein, not CYP2D2, was responsible for the inter- and intrastrain differences in diazepam p-hydroxylation (Drug Metab Dispos 33:1657-1660, 2005). Quantitative real-time polymerase chain reaction (PCR) did not provide enough evidence to explain the inter- and intrastrain differences in the expression of CYP2D3 protein. Nucleotide sequence analysis revealed the insertion of a thymine in exon 8 of the CYP2D3 gene in the poor diazepam metabolizers. This single nucleotide mutation caused a shift in the reading frame and introduced a premature termination signal. It is noteworthy that the heme binding region, which is essential to maintain proper heme binding and active cytochrome P450 enzymes, was consequently deleted by the premature termination signal. In contrast, no mutation was detected in the CYP2D3 gene of extensive metabolizers. Thus, the truncated CYP2D3 must be a nonfunctional enzyme in poor metabolizers. In addition, we developed a convenient and specific genotyping assay using PCR-restriction, fragment-length polymorphism to distinguish homozygotes from heterozygotes. The genotyping gave results fully consistent with those of the inter- and intrastrain differences in diazepam p-hydroxylation.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Diazepam/metabolismo , Hidroxilação , Ratos/genética , Especificidade da Espécie , Animais , Ansiolíticos , Sistema Enzimático do Citocromo P-450/genética , Expressão Gênica , Microssomos Hepáticos/enzimologia , Ratos/classificação , Ratos Sprague-Dawley , Ratos Wistar
19.
Sci Rep ; 9(1): 477, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679597

RESUMO

Narcolepsy is a chronic sleep disorder caused by a loss of hypocretin (hcrt) neurons in the hypothalamus. Cerebrospinal fluid (CSF) hcrt-1 measurement has been well established as a gold standard of narcolepsy diagnosis, although some portions of narcoleptic patients show normal hcrt-1 levels. We aimed to examine peptide degradation of hcrt-1 and its abnormality in the CSF of patients by using high performance liquid chromatography (HPLC) followed by radioimmunoassay (RIA). CSF was collected from healthy controls, narcoleptic patients of type 1 with hcrt-1 deficiency, type 1 with normal hcrt-1 level, and type 2 with normal hcrt-1 level. We found that the majority of hcrt-1 immunoreactivity in extracted CSF was derived from unauthentic hcrt-1 peaks, which are predicted to be inactive metabolites, and the intact hcrt-1 peptide was less than 10% of the gross amount, suggesting that the regular RIA for CSF hcrt-1 measures largely reflect the unauthentic hcrt-1-related metabolites rather than the intact one. As expected, all hcrt-1-related peaks were abolished in type 1 with hcrt-1 deficiency. Importantly, we also found that the sum of the authentic hcrt-1 peptide (peaks 3 and 4) significantly decreased in non-deficient type 1 and tended to decrease in type 2 narcoleptic patients although the levels with the regular RIA in non-extracted CSF was equivalent to healthy controls. Immunoreactivity with unauthentic hcrt-1 metabolites may masks the possible decline in authentic hcrt-1 level caused by the partial loss of hcrt neurons. Our findings may provide new insights into the degradation of the hcrt-1 peptide and the pathophysiology of narcolepsy.


Assuntos
Biomarcadores , Cromatografia Líquida de Alta Pressão , Narcolepsia/líquido cefalorraquidiano , Narcolepsia/diagnóstico , Orexinas/líquido cefalorraquidiano , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Narcolepsia/terapia , Peptídeos/líquido cefalorraquidiano , Radioimunoensaio
20.
Radiat Prot Dosimetry ; 184(3-4): 523-526, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31172180

RESUMO

Public opinion on the application of nuclear technology and radiation could change when a nuclear related event occurs. Japan Atomic Energy Relations Organization has tracked its variation through a nationwide opinion survey in Japan by almost the same way every year since FY 2006. We can identify a continuous long-term fluctuation of Japanese opinion before and after the TEPCO Fukushima Daiichi nuclear disaster using the data. In this study we focused on the trends of public opinion for nuclear energy, impressions and knowledge on radiation, and zero-risk request. For example, radiation can be recognised that it is dangerous and complicated matter by Japanese public regardless of that accident. However, a big change of opinions on radiation was shown on the impression for the word of 'Useful' between before and after the accident.


Assuntos
Medicina Nuclear , Centrais Nucleares , Opinião Pública , Liberação Nociva de Radioativos/estatística & dados numéricos , Radiobiologia , Radioterapia , Acidente Nuclear de Fukushima , Humanos , Inquéritos e Questionários
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