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1.
Sleep Adv ; 5(1): zpae022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638581

RESUMO

Sleep-wake scoring is a time-consuming, tedious but essential component of clinical and preclinical sleep research. Sleep scoring is even more laborious and challenging in rodents due to the smaller EEG amplitude differences between states and the rapid state transitions which necessitate scoring in shorter epochs. Although many automated rodent sleep scoring methods exist, they do not perform as well when scoring new datasets, especially those which involve changes in the EEG/EMG profile. Thus, manual scoring by expert scorers remains the gold standard. Here we take a different approach to this problem by using a neural network to accelerate the scoring of expert scorers. Sleep-Deep-Learner creates a bespoke deep convolution neural network model for individual electroencephalographic or local-field-potential (LFP) records via transfer learning of GoogLeNet, by learning from a small subset of manual scores of each EEG/LFP record as provided by the end-user. Sleep-Deep-Learner then automates scoring of the remainder of the EEG/LFP record. A novel REM sleep scoring correction procedure further enhanced accuracy. Sleep-Deep-Learner reliably scores EEG and LFP data and retains sleep-wake architecture in wild-type mice, in sleep induced by the hypnotic zolpidem, in a mouse model of Alzheimer's disease and in a genetic knock-down study, when compared to manual scoring. Sleep-Deep-Learner reduced manual scoring time to 1/12. Since Sleep-Deep-Learner uses transfer learning on each independent recording, it is not biased by previously scored existing datasets. Thus, we find Sleep-Deep-Learner performs well when used on signals altered by a drug, disease model, or genetic modification.

2.
bioRxiv ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38464146

RESUMO

Sleep spindles are critical for memory consolidation and strongly linked to neurological disease and aging. Despite their significance, the relative influences of factors like sleep depth, cortical up/down states, and spindle temporal patterns on individual spindle production remain poorly understood. Moreover, spindle temporal patterns are typically ignored in favor of an average spindle rate. Here, we analyze spindle dynamics in 1008 participants from the Multi-Ethnic Study of Atherosclerosis using a point process framework. Results reveal fingerprint-like temporal patterns, characterized by a refractory period followed by a period of increased spindle activity, which are highly individualized yet consistent night-to-night. We observe increased timing variability with age and distinct gender/age differences. Strikingly, and in contrast to the prevailing notion, individualized spindle patterns are the dominant determinant of spindle timing, accounting for over 70% of the statistical deviance explained by all of the factors we assessed, surpassing the contribution of slow oscillation (SO) phase (~14%) and sleep depth (~16%). Furthermore, we show spindle/SO coupling dynamics with sleep depth are preserved across age, with a global negative shift towards the SO rising slope. These findings offer novel mechanistic insights into spindle dynamics with direct experimental implications and applications to individualized electroencephalography biomarker identification.

3.
Angew Chem Int Ed Engl ; 63(9): e202317062, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38150287

RESUMO

Postsynthetic modification (PSM) of metal-organic frameworks (MOFs) provides access to functional materials and advanced porous solid engineering. Herein, we report the reversible PSM of a multivariate isoreticular MOF by applying dynamic furan-maleimide Diels-Alder (DA) chemistry. The key step involves incorporating a furan group into the MOF via "click" PSM, which can then undergo repeated cycles of modification and de-modification with maleimides. The structural integrity, crystallinity, and porosity of the furan-appended MOF remained intact even after three consecutive PSM/de-modification cycles using three different functionalized maleimides.

4.
bioRxiv ; 2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37986953

RESUMO

Here we describe a novel group of basal forebrain (BF) neurons expressing neuronal PAS domain 1 (Npas1), a developmental transcription factor linked to neuropsychiatric disorders. Immunohistochemical staining in Npas1-cre-2A-TdTomato mice revealed BF Npas1 + neurons are distinct from well-studied parvalbumin or cholinergic neurons. Npas1 staining in GAD67-GFP knock-in mice confirmed that the vast majority of Npas1 + neurons are GABAergic, with minimal colocalization with glutamatergic neurons in vGlut1-cre-tdTomato or vGlut2-cre-tdTomato mice. The density of Npas1 + neurons was high, 5-6 times that of neighboring cholinergic, parvalbumin or glutamatergic neurons. Anterograde tracing identified prominent projections of BF Npas1 + neurons to brain regions involved in sleep-wake control, motivated behaviors and olfaction such as the lateral hypothalamus, lateral habenula, nucleus accumbens shell, ventral tegmental area and olfactory bulb. Chemogenetic activation of BF Npas1 + neurons in the light (inactive) period increased the amount of wakefulness and the latency to sleep for 2-3 hr, due to an increase in long wake bouts and short NREM sleep bouts. Non-REM slow-wave (0-1.5 Hz) and sigma (9-15 Hz) power, as well as sleep spindle density, amplitude and duration, were reduced, reminiscent of findings in several neuropsychiatric disorders. Together with previous findings implicating BF Npas1 + neurons in stress responsiveness, the anatomical projections of BF Npas1 + neurons and the effect of activating them suggest a possible role for BF Npas1 + neurons in motivationally-driven wakefulness and stress-induced insomnia. Identification of this major subpopulation of BF GABAergic neurons will facilitate studies of their role in sleep disorders, dementia and other neuropsychiatric conditions involving BF. SIGNIFICANCE STATEMENT: We characterize a group of basal forebrain (BF) neurons in the mouse expressing neuronal PAS domain 1 (Npas1), a developmental transcription factor linked to neuropsychiatric disorders. BF Npas1 + neurons are a major subset of GABAergic neurons distinct and more numerous than cholinergic, parvalbumin or glutamate neurons. BF Npas1 + neurons target brain areas involved in arousal, motivation and olfaction. Activation of BF Npas1 + neurons in the light (inactive) period increased wakefulness and the latency to sleep due to increased long wake bouts. Non-REM sleep slow waves and spindles were reduced reminiscent of findings in several neuropsychiatric disorders. Identification of this major subpopulation of BF GABAergic wake-promoting neurons will allow studies of their role in insomnia, dementia and other conditions involving BF.

5.
J Sleep Res ; : e13919, 2023 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-37211393

RESUMO

Attention is impaired in many neuropsychiatric disorders, as well as by sleep disruption, leading to decreased workplace productivity and increased risk of accidents. Thus, understanding the neural substrates is important. Here we test the hypothesis that basal forebrain neurons that contain the calcium-binding protein parvalbumin modulate vigilant attention in mice. Furthermore, we test whether increasing the activity of basal forebrain parvalbumin neurons can rescue the deleterious effects of sleep deprivation on vigilance. A lever release version of the rodent psychomotor vigilance test was used to assess vigilant attention. Brief and continuous low-power optogenetic excitation (1 s, 473 nm @ 5 mW) or inhibition (1 s, 530 nm @ 10 mW) of basal forebrain parvalbumin neurons was used to test the effect on attention, as measured by reaction time, under control conditions and following 8 hr of sleep deprivation by gentle handling. Optogenetic excitation of basal forebrain parvalbumin neurons that preceded the cue light signal by 0.5 s improved vigilant attention as indicated by quicker reaction times. By contrast, both sleep deprivation and optogenetic inhibition slowed reaction times. Importantly, basal forebrain parvalbumin excitation rescued the reaction time deficits in sleep-deprived mice. Control experiments using a progressive ratio operant task confirmed that optogenetic manipulation of basal forebrain parvalbumin neurons did not alter motivation. These findings reveal for the first time a role for basal forebrain parvalbumin neurons in attention, and show that increasing their activity can compensate for disruptive effects of sleep deprivation.

6.
Front Neurosci ; 17: 1133907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36733335
7.
bioRxiv ; 2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38187568

RESUMO

Sleep-wake scoring is a time-consuming, tedious but essential component of clinical and pre-clinical sleep research. Sleep scoring is even more laborious and challenging in rodents due to the smaller EEG amplitude differences between states and the rapid state transitions which necessitate scoring in shorter epochs. Although many automated rodent sleep scoring methods exist, they do not perform as well when scoring new data sets, especially those which involve changes in the EEG/EMG profile. Thus, manual scoring by expert scorers remains the gold-standard. Here we take a different approach to this problem by using a neural network to accelerate the scoring of expert scorers. Sleep-Deep-Net (SDN) creates a bespoke deep convolution neural network model for individual electroencephalographic or local-field-potential records via transfer learning of GoogleNet, by learning from a small subset of manual scores of each EEG/LFP record as provided by the end-user. SDN then automates scoring of the remainder of the EEG/LFP record. A novel REM scoring correction procedure further enhanced accuracy. SDN reliably scores EEG and LFP data and retains sleep-wake architecture in wild-type mice, in sleep induced by the hypnotic zolpidem, in a mouse model of Alzheimer's disease and in a genetic knock-down study, when compared to manual scoring. SDN reduced manual scoring time to 1/12. Since SDN uses transfer learning on each independent recording, it is not biased by previously scored existing data sets. Thus, we find SDN performs well when used on signals altered by a drug, disease model or genetic modification.

8.
9.
Sports Med ; 52(12): 3055-3064, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35904751

RESUMO

AIM: Defining universally accepted guidelines for the diagnosis and treatment of chronic exertional compartment syndrome (CECS) is hampered by the absence of high-quality scientific research. The aim of this Delphi study was to establish consensus on practical issues guiding diagnosis and treatment of CECS of the leg in civilian and military patient populations. METHODS: An international expert group was queried using the Delphi technique with a traditional three-round electronic consultation. Results of previous rounds were anonymously disclosed in the questionnaire of rounds 2 and 3, if relevant. Consensus was defined as > 70% positive or negative agreement for a question or statement. RESULTS: The panel consisted of 27 civilian and military healthcare providers. Consensus was reached on five essential key characteristics of lower leg CECS. The panel achieved partial agreement regarding standardization of the diagnostic protocol, including muscle tissue pressure measurements. Consensus was reached on conservative and surgical treatment regimens. However, the experts did not attain consensus on their approach of postoperative rehabilitation and preferred treatment approach of recurrent or residual disease. A summary of best clinical practice for the diagnosis and management of CECS was formulated by experts working in civilian and military healthcare facilities. CONCLUSION: The Delphi panel reached consensus on key criteria for signs and symptoms of CECS and several aspects for conservative and surgical treatment. The panel did not agree on the role of ICP values in the diagnostic process, postoperative rehabilitation guidelines protocol, or the preferred treatment approach for recurrent or residual disease. These aspects serve as a first attempt to initiate simple guidelines for clinical practice.


Assuntos
Síndrome Compartimental Crônica do Esforço , Síndromes Compartimentais , Humanos , Consenso , Perna (Membro) , Síndromes Compartimentais/diagnóstico , Síndromes Compartimentais/cirurgia , Inquéritos e Questionários
10.
Brain Res Bull ; 187: 181-198, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35850189

RESUMO

Sleep abnormalities are widely reported in patients with Alzheimer's disease (AD) and are linked to cognitive impairments. Sleep abnormalities could be potential biomarkers to detect AD since they are often observed at the preclinical stage. Moreover, sleep could be a target for early intervention to prevent or slow AD progression. Thus, here we review changes in brain oscillations observed during sleep, their connection to AD pathophysiology and the role of specific brain circuits. Slow oscillations (0.1-1 Hz), sleep spindles (8-15 Hz) and their coupling during non-REM sleep are consistently reduced in studies of patients and in AD mouse models although the timing and magnitude of these alterations depends on the pathophysiological changes and the animal model studied. Changes in delta (1-4 Hz) activity are more variable. Animal studies suggest that hippocampal sharp-wave ripples (100-250 Hz) are also affected. Reductions in REM sleep amount and slower oscillations during REM are seen in patients but less consistently in animal models. Thus, changes in a variety of sleep oscillations could impact sleep-dependent memory consolidation or restorative functions of sleep. Recent mechanistic studies suggest that alterations in the activity of GABAergic neurons in the cortex, hippocampus and thalamic reticular nucleus mediate sleep oscillatory changes in AD and represent a potential target for intervention. Longitudinal studies of the timing of AD-related sleep abnormalities with respect to pathology and dysfunction of specific neural networks are needed to identify translationally relevant biomarkers and guide early intervention strategies to prevent or delay AD progression.


Assuntos
Doença de Alzheimer , Neurônios GABAérgicos , Animais , Eletroencefalografia , Neurônios GABAérgicos/fisiologia , Hipocampo/fisiologia , Camundongos , Sono/fisiologia , Tálamo/fisiologia
11.
Brain Res Bull ; 185: 140-161, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35550156

RESUMO

Sleep disorders are widespread in society and are prevalent in military personnel and in Veterans. Disturbances of sleep and arousal mechanisms are common in neuropsychiatric disorders such as schizophrenia, post-traumatic stress disorder, anxiety and affective disorders, traumatic brain injury, dementia, and substance use disorders. Sleep disturbances exacerbate suicidal ideation, a major concern for Veterans and in the general population. These disturbances impair quality of life, affect interpersonal relationships, reduce work productivity, exacerbate clinical features of other disorders, and impair recovery. Thus, approaches to improve sleep and modulate arousal are needed. Basic science research on the brain circuitry controlling sleep and arousal led to the recent approval of new drugs targeting the orexin/hypocretin and histamine systems, complementing existing drugs which affect GABAA receptors and monoaminergic systems. Non-invasive brain stimulation techniques to modulate sleep and arousal are safe and show potential but require further development to be widely applicable. Invasive viral vector and deep brain stimulation approaches are also in their infancy but may be used to modulate sleep and arousal in severe neurological and psychiatric conditions. Behavioral, pharmacological, non-invasive brain stimulation and cell-specific invasive approaches covered here suggest the potential to selectively influence arousal, sleep initiation, sleep maintenance or sleep-stage specific phenomena such as sleep spindles or slow wave activity. These manipulations can positively impact the treatment of a wide range of neurological and psychiatric disorders by promoting the restorative effects of sleep on memory consolidation, clearance of toxic metabolites, metabolism, and immune function and by decreasing hyperarousal.


Assuntos
Transtornos do Sono-Vigília , Veteranos , Nível de Alerta , Humanos , Qualidade de Vida , Sono , Transtornos do Sono-Vigília/terapia , Veteranos/psicologia
12.
Opt Express ; 30(7): 11619-11632, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473102

RESUMO

As scattering-scanning near-field optical microscopy (s-SNOM) continues to grow in prominence, there has been great interest in modeling the near-field light-matter interaction to better predict experimental results. Both analytical and numerical models have been developed to describe the near-field response, but thus far models have not incorporated the full range of phenomena accessible. Here, we present a finite element model (FEM), capable of incorporating the complex physical and spatial phenomena that s-SNOM has proved able to probe. First, we use electromagnetic FEM to simulate the multipolar response of the tip and illustrate the impact of strong coupling on signal demodulation. We then leverage the multiphysics advantage of FEM to study the electrostatic effect of metallic tips on semiconductors, finding that THz s-SNOM studies are most impacted by this tip-induced band-bending. Our model is computationally inexpensive and can be tailored to specific nanostructured systems and geometries of interest.

13.
Nat Commun ; 13(1): 2246, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35473906

RESUMO

Identification of mechanisms which increase deep sleep could lead to novel treatments which promote the restorative effects of sleep. Here, we show that knockdown of the α3 GABAA-receptor subunit from parvalbumin neurons in the thalamic reticular nucleus using CRISPR-Cas9 gene editing increased the thalamocortical delta (1.5-4 Hz) oscillations which are implicated in many health-promoting effects of sleep. Inhibitory synaptic currents in thalamic reticular parvalbumin neurons were strongly reduced in vitro. Further analysis revealed that delta power in long NREM bouts prior to NREM-REM transitions was preferentially affected by deletion of α3 subunits. Our results identify a role for GABAA receptors on thalamic reticular nucleus neurons and suggest antagonism of α3 subunits as a strategy to enhance delta activity during sleep.


Assuntos
Parvalbuminas , Sono de Ondas Lentas , Animais , Camundongos , Neurônios/metabolismo , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Tálamo/fisiologia , Ácido gama-Aminobutírico
14.
J Biomech ; 135: 111026, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35288313

RESUMO

The aim of this study was to compare commercially available manometers and needles used for intracompartmental pressure measurements for accuracy. An experimental compartment simulation model was developed in order to compare four different terminal devices (Compass manometer, Stryker device, Meritrans transducer, and arterial line) and 22 types of needles. First, all possible device/needle combinations were introduced in rubber ports at the bottom of a water column. The water column was gradually drained three times for each device/needle combination and pressures were recorded by two researchers. This procedure was repeated after placement of a sample of homogenous porcine gluteal muscle tissue. When measuring the fluid column only, all Intraclass Correlation Coefficients were found to be ≥0.980, indicating good resemblance to the reference pressure. After addition of the muscle tissue to the experimental set up, accuracy of the Stryker device and arterial line remained the same. The accuracy of the Compass manometer and Meritrans transducer became less. Excellent reliability was found for 7 out of 22 needles when combined with the Stryker device and for 2 out of 22 needles when combined with the arterial line. The four terminal devices tested were all accurate when measuring pressure in a water column, whereas only the Stryker device and arterial line accurately represented the water column pressure in a porcine gluteal muscle model. Future research will have to verify whether these results can be repeated in human cadaver models and in vivo.


Assuntos
Síndrome Compartimental Crônica do Esforço , Síndromes Compartimentais , Animais , Músculo Esquelético , Reprodutibilidade dos Testes , Suínos , Água
15.
Brain Struct Funct ; 226(6): 1755-1778, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33997911

RESUMO

The basal forebrain (BF) is involved in arousal, attention, and reward processing but the role of individual BF neuronal subtypes is still being uncovered. Glutamatergic neurons are the least well-understood of the three main BF neurotransmitter phenotypes. Here we analyzed the distribution, size, calcium-binding protein content and projections of the major group of BF glutamatergic neurons expressing the vesicular glutamate transporter subtype 2 (vGluT2) and tested the functional effect of activating them. Mice expressing Cre recombinase under the control of the vGluT2 promoter were crossed with a reporter strain expressing the red fluorescent protein, tdTomato, to generate vGluT2-cre-tdTomato mice. Immunohistochemical staining for choline acetyltransferase and a cross with mice expressing green fluorescent protein selectively in GABAergic neurons confirmed that cholinergic, GABAergic and vGluT2+ neurons represent distinct BF subpopulations. Subsets of BF vGluT2+ neurons expressed the calcium-binding proteins calbindin or calretinin, suggesting that multiple subtypes of BF vGluT2+ neurons exist. Anterograde tracing using adeno-associated viral vectors expressing channelrhodopsin2-enhanced yellow fluorescent fusion proteins revealed major projections of BF vGluT2+ neurons to neighboring BF cholinergic and parvalbumin neurons, as well as to extra-BF areas involved in the control of arousal or aversive/rewarding behavior such as the lateral habenula and ventral tegmental area. Optogenetic activation of BF vGluT2+ neurons elicited a striking avoidance of the area where stimulation was given, whereas stimulation of BF parvalbumin or cholinergic neurons did not. Together with previous optogenetic findings suggesting an arousal-promoting role, our findings suggest that BF vGluT2 neurons play a dual role in promoting wakefulness and avoidance behavior.


Assuntos
Prosencéfalo Basal , Animais , Aprendizagem da Esquiva , Prosencéfalo Basal/metabolismo , Colinérgicos , Neurônios Colinérgicos/metabolismo , Ácido Glutâmico , Camundongos , Parvalbuminas/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/genética , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo , Vigília
16.
Proc Biol Sci ; 288(1945): 20202966, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33622122

RESUMO

Research on the 'ecology of fear' posits that defensive prey responses to avoid predation can cause non-lethal effects across ecological scales. Parasites also elicit defensive responses in hosts with associated non-lethal effects, which raises the longstanding, yet unresolved question of how non-lethal effects of parasites compare with those of predators. We developed a framework for systematically answering this question for all types of predator-prey and host-parasite systems. Our framework reveals likely differences in non-lethal effects not only between predators and parasites, but also between different types of predators and parasites. Trait responses should be strongest towards predators, parasitoids and parasitic castrators, but more numerous and perhaps more frequent for parasites than for predators. In a case study of larval amphibians, whose trait responses to both predators and parasites have been relatively well studied, existing data indicate that individuals generally respond more strongly and proactively to short-term predation risks than to parasitism. Apart from studies using amphibians, there have been few direct comparisons of responses to predation and parasitism, and none have incorporated responses to micropredators, parasitoids or parasitic castrators, or examined their long-term consequences. Addressing these and other data gaps highlighted by our framework can advance the field towards understanding how non-lethal effects impact prey/host population dynamics and shape food webs that contain multiple predator and parasite species.


Assuntos
Parasitos , Comportamento Predatório , Animais , Medo , Cadeia Alimentar , Humanos , Dinâmica Populacional
17.
BMJ Mil Health ; 167(6): 387-392, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32019808

RESUMO

INTRODUCTION: Exercise-related leg pain (ERLP) may be caused by chronic exertional compartment syndrome (CECS), occurring mainly in athletes and military recruits. In military populations, the effectiveness of surgical treatment in CECS is debated. The purpose of this study is to assess the outcome of surgical treatment for CECS in Alrijne Hospital (the Netherlands), a civilian hospital with supraregional referral function. METHODS: A historic cohort study was performed on patients with ERLP who were suspected for CECS and were referred for intracompartmental pressure measurement (ICPM) from 2013 to 2017 (n=160). Patient demographics, ICPM and survey response were analysed. RESULTS: The mean delay before visitation was 29.0±30.3 months. When comparing surgical-treated patients with CECS with conservative-treated patients with ERLP, surgical-treated patients were more satisfied, reported better recovery towards former level of performance (2.8±2.0 vs 3.9±1.7 and 2.5±1.6 vs 3.2±1.4 on a 7-point Likert scale, respectively) and better subjective injury status (79.3±22.6 vs 63.5±27.4 using the Single Assessment Numeric Evaluation score). Treatment satisfaction was 75.0% in surgical-treated CECS versus 51.4% in conservative-treated ERLP. CONCLUSION: Civilian patients report improved functional outcomes after fasciotomy for CECS. Future research should focus on non-invasive diagnostic options and methods to determine which treatment is the most appropriate for each individual patient.


Assuntos
Síndrome Compartimental Crônica do Esforço , Síndromes Compartimentais , Estudos de Coortes , Síndromes Compartimentais/etiologia , Fasciotomia , Humanos , Perna (Membro)
18.
Mol Psychiatry ; 26(7): 3461-3475, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32690865

RESUMO

Increases in broadband cortical electroencephalogram (EEG) power in the gamma band (30-80 Hz) range have been observed in schizophrenia patients and in mouse models of schizophrenia. They are also seen in humans and animals treated with the psychotomimetic agent ketamine. However, the mechanisms which can result in increased broadband gamma power and the pathophysiological implications for cognition and behavior are poorly understood. Here we report that tonic optogenetic manipulation of an ascending arousal system bidirectionally tunes cortical broadband gamma power, allowing on-demand tests of the effect on cortical processing and behavior. Constant, low wattage optogenetic stimulation of basal forebrain (BF) neurons containing the calcium-binding protein parvalbumin (PV) increased broadband gamma frequency power, increased locomotor activity, and impaired novel object recognition. Concomitantly, task-associated gamma band oscillations induced by trains of auditory stimuli, or exposure to novel objects, were impaired, reminiscent of findings in schizophrenia patients. Conversely, tonic optogenetic inhibition of BF-PV neurons partially rescued the elevated broadband gamma power elicited by subanesthetic doses of ketamine. These results support the idea that increased cortical broadband gamma activity leads to impairments in cognition and behavior, and identify BF-PV activity as a modulator of this activity. As such, BF-PV neurons may represent a novel target for pharmacotherapy in disorders such as schizophrenia which involve aberrant increases in cortical broadband gamma activity.


Assuntos
Prosencéfalo Basal , Esquizofrenia , Animais , Nível de Alerta , Prosencéfalo Basal/metabolismo , Eletroencefalografia , Humanos , Camundongos , Optogenética , Parvalbuminas/metabolismo , Esquizofrenia/genética
19.
Curr Biol ; 30(12): 2379-2385.e4, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32413301

RESUMO

The ability to rapidly arouse from sleep is important for survival. However, increased arousals in patients with sleep apnea and other disorders prevent restful sleep and contribute to cognitive, metabolic, and physiologic dysfunction [1, 2]. Little is currently known about which neural systems mediate these brief arousals, hindering the development of treatments that restore normal sleep. The basal forebrain (BF) receives inputs from many nuclei of the ascending arousal system, including the brainstem parabrachial neurons, which promote arousal in response to elevated blood carbon dioxide levels, as seen in sleep apnea [3]. Optical inhibition of the terminals of parabrachial neurons in the BF impairs cortical arousals to hypercarbia [4], but which BF cell types mediate cortical arousals in response to hypercarbia or other sensory stimuli is unknown. Here, we tested the role of BF parvalbumin (PV) neurons in arousal using optogenetic techniques in mice. Optical stimulation of BF-PV neurons produced rapid transitions to wakefulness from non-rapid eye movement (NREM) sleep but did not affect REM-wakefulness transitions. Unlike previous studies of BF glutamatergic and cholinergic neurons, arousals induced by stimulation of BF-PV neurons were brief and only slightly increased total wake time, reminiscent of clinical findings in sleep apnea [5, 6]. Bilateral optical inhibition of BF-PV neurons increased the latency to arousal produced by exposure to hypercarbia or auditory stimuli. Thus, BF-PV neurons are an important component of the brain circuitry that generates brief arousals from sleep in response to stimuli, which may indicate physiological dysfunction or danger to the organism.


Assuntos
Estimulação Acústica , Nível de Alerta/fisiologia , Carboidratos/administração & dosagem , Neurônios/fisiologia , Ração Animal/análise , Animais , Prosencéfalo Basal/fisiologia , Dieta , Camundongos , Parvalbuminas/metabolismo , Sono/fisiologia , Vigília/fisiologia
20.
Transl Psychiatry ; 10(1): 29, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-32066662

RESUMO

CACNA1I, a schizophrenia risk gene, encodes a subtype of voltage-gated T-type calcium channel CaV3.3. We previously reported that a patient-derived missense de novo mutation (R1346H) of CACNA1I impaired CaV3.3 channel function. Here, we generated CaV3.3-RH knock-in animals, along with mice lacking CaV3.3, to investigate the biological impact of R1346H (RH) variation. We found that RH mutation altered cellular excitability in the thalamic reticular nucleus (TRN), where CaV3.3 is abundantly expressed. Moreover, RH mutation produced marked deficits in sleep spindle occurrence and morphology throughout non-rapid eye movement (NREM) sleep, while CaV3.3 haploinsufficiency gave rise to largely normal spindles. Therefore, mice harboring the RH mutation provide a patient derived genetic model not only to dissect the spindle biology but also to evaluate the effects of pharmacological reagents in normalizing sleep spindle deficits. Importantly, our analyses highlighted the significance of characterizing individual spindles and strengthen the inferences we can make across species over sleep spindles. In conclusion, this study established a translational link between a genetic allele and spindle deficits during NREM observed in schizophrenia patients, representing a key step toward testing the hypothesis that normalizing spindles may be beneficial for schizophrenia patients.


Assuntos
Canais de Cálcio Tipo T , Esquizofrenia , Animais , Eletroencefalografia , Humanos , Camundongos , Esquizofrenia/genética , Sono , Sono REM
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