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1.
Sci Rep ; 14(1): 12101, 2024 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802558

RESUMO

Anxiety is among the most fundamental mammalian behaviors. Despite the physiological and pathological importance, its underlying neural mechanisms remain poorly understood. Here, we recorded the activity of olfactory bulb (OB) and medial prefrontal cortex (mPFC) of rats, which are critical structures to brain's emotional processing network, while exploring different anxiogenic environments. Our results show that presence in anxiogenic contexts increases the OB and mPFC regional theta activities. Also, these local activity changes are associated with enhanced OB-mPFC theta power- and phase-based functional connectivity as well as OB-to-mPFC information transfer. Interestingly, these effects are more prominent in the unsafe zones of the anxiogenic environments, compared to safer zones. This consistent trend of changes in diverse behavioral environments as well as local and long-range neural activity features suggest that the dynamics of OB-mPFC circuit theta oscillations might underlie different types of anxiety behaviors, with possible implications for anxiety disorders.


Assuntos
Ansiedade , Bulbo Olfatório , Córtex Pré-Frontal , Ritmo Teta , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/fisiopatologia , Animais , Ansiedade/fisiopatologia , Ritmo Teta/fisiologia , Bulbo Olfatório/fisiologia , Bulbo Olfatório/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Comportamento Animal/fisiologia
2.
Brain Sci ; 14(4)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38672027

RESUMO

This study aimed to investigate the effects of intranasal air-puffing on cognitive impairments and brain cortical activity following one night of partial sleep deprivation (PSD) in adults. A total of 26 healthy adults underwent the numerical Stroop test (NST) and electroencephalography (EEG) before and after one night of PSD. Following PSD, subjects in the treatment group (n = 13) received nasal air-puffs (5 Hz, 3 min) before beginning the NST and EEG recording. Administration of nasal air-puffs in the treatment group restored the PSD-induced increase in error rate and decrease in reaction time and missing rate in the NST. Intranasal air-puffs recovered the PSD-induced augmentation of delta and theta power and the reduction of beta and gamma power in the EEG, particularly in the frontal lobes. Intranasal air-puffing also almost reversed the PSD-induced decrease in EEG signal complexity. Furthermore, it had a restorative effect on PSD-induced alteration in intra-default mode network functional connectivity in the beta and gamma frequency bands. Rhythmic nasal air-puffing can mitigate acute PSD-induced impairments in cognitive functions. It exerts part of its ameliorating effect by restoring neuronal activity in cortical brain areas involved in cognitive processing.

3.
Rev Neurosci ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579456

RESUMO

While breathing is a vital, involuntary physiological function, the mode of respiration, particularly nasal breathing, exerts a profound influence on brain activity and cognitive processes. This review synthesizes existing research on the interactions between nasal respiration and the entrainment of oscillations across brain regions involved in cognition. The rhythmic activation of olfactory sensory neurons during nasal respiration is linked to oscillations in widespread brain regions, including the prefrontal cortex, entorhinal cortex, hippocampus, amygdala, and parietal cortex, as well as the piriform cortex. The phase-locking of neural oscillations to the respiratory cycle, through nasal breathing, enhances brain inter-regional communication and is associated with cognitive abilities like memory. Understanding the nasal breathing impact on brain networks offers opportunities to explore novel methods for targeting the olfactory pathway as a means to enhance emotional and cognitive functions.

4.
CNS Neurosci Ther ; 30(3): e14656, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38439573

RESUMO

AIMS: In this study, the anticonvulsant action of closed-loop, low-frequency deep brain stimulation (DBS) was investigated. In addition, the changes in brain rhythms and functional connectivity of the hippocampus and prefrontal cortex were evaluated. METHODS: Epilepsy was induced by pilocarpine in male Wistar rats. After the chronic phase, a tripolar electrode was implanted in the right ventral hippocampus and a monopolar electrode in medial prefrontal cortex (mPFC). Subjects' spontaneous seizure behaviors were observed in continuous video recording, while the local field potentials (LFPs) were recorded simultaneously. In addition, spatial memory was evaluated by the Barnes maze test. RESULTS: Applying hippocampal DBS, immediately after seizure detection in epileptic animals, reduced their seizure severity and duration, and improved their performance in Barnes maze test. DBS reduced the increment in power of delta, theta, and gamma waves in pre-ictal, ictal, and post-ictal periods. Meanwhile, DBS increased the post-ictal-to-pre-ictal ratio of theta band. DBS decreased delta and increased theta coherences, and also increased the post-ictal-to-pre-ictal ratio of coherence. In addition, DBS increased the hippocampal-mPFC coupling in pre-ictal period and decreased the coupling in the ictal and post-ictal periods. CONCLUSION: Applying closed-loop, low-frequency DBS at seizure onset reduced seizure severity and improved memory. In addition, the changes in power, coherence, and coupling of the LFP oscillations in the hippocampus and mPFC demonstrate low-frequency DBS efficacy as an antiepileptic treatment, returning LFPs to a seemingly non-seizure state in subjects that received DBS.


Assuntos
Epilepsia , Pilocarpina , Humanos , Masculino , Ratos , Animais , Pilocarpina/toxicidade , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/terapia , Anticonvulsivantes , Hipocampo , Aprendizagem em Labirinto
5.
J Photochem Photobiol B ; 252: 112852, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38330690

RESUMO

Infertility is such an important issue in society today. In some cases of male infertility, the main cause is oxidative stress and the presence of reactive oxygen species in the environment or in sperm cells. All current techniques that measure oxidative stress, including the nitroblue tetrazolium Test, DNA Fragmentation Index, Malondialdehyde, and Endz Test are qualitative and semi-quantitative. These methods do not have good sensitivity and specificity. Semen samples from 50 infertile patients and 10 normal individuals were collected. The samples were examined for laboratory routine tests according to the WHO 2010 protocol. Oxidative stress tests, including DFI, NBT, and MDA, were performed for these two groups. Bioluminescence inhibition assay was performed for detection of O2.- in semen samples by aequorin. The normal individuals showed significantly better semen parameters than the patient's group. Significantly lower O2.- levels were seen in the patient's group compared to normal individuals. The cut-off value of O2.- levels in normal individuals was determined to be 8 × 105 RLU/s with a sensitivity of 100% and a specificity of 100%. Infertile patients, despite having reduced quality of semen parameters, have high O2.- levels, and this causes the intensity of bioluminescence to be quenched in these people.


Assuntos
Infertilidade Masculina , Superóxidos , Humanos , Masculino , Superóxidos/metabolismo , Sêmen , Fragmentação do DNA , Motilidade dos Espermatozoides , Estresse Oxidativo/fisiologia , Infertilidade Masculina/diagnóstico , Espermatozoides/metabolismo
6.
Front Hum Neurosci ; 18: 1338966, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38375364

RESUMO

Introduction: Stuttering is a speech disorder characterized by impaired connections between brain regions involved in speech production. This study aimed to investigate functional connectivity and frequency power during rest in adults who stutter (AWS) compared to fluent adults (AWNS) in the dorsolateral prefrontal cortex (DLPFC), dorsolateral frontal cortex (DLFC), supplementary motor area (SMA), motor speech, angular gyrus (AG), and inferior temporal gyrus (ITG). Materials and methods: Fifteen AWS (3 females, 12 males) and fifteen age- and sex-matched AWNS (3 females, 12 males) participated in this study. All participants were native Persian speakers. Stuttering severity in the AWS group was assessed using the Persian version of the Stuttering Severity Instrument Fourth Edition (SSI-4). Resting-state electroencephalography (EEG) was recorded for 5 min while participants sat comfortably with their eyes open. We analyzed frequency band power across various frequency bands and investigated functional connectivity within the specified speech region. Results: Significant between-group differences were found in band powers including alpha, beta, delta, theta, and gamma, specifically in the premotor, SMA, motor speech, and frontal regions. AWS also showed increased coherence between the right motor speech region compared to controls. We demonstrate that the proposed hierarchical false discovery rate (FDR) method is the most effective for both simulations and experimental data. In the expected regions, this method revealed significant synchrony effects at an acceptable error rate of 5%. Conclusion: The results highlight disrupted functional connectivity in AWS at resting state, particularly in speech-related and associated areas. Given the complex neurological basis of developmental stuttering, robust neural markers are closely linked to this phenomenon. These markers include imbalanced activity within brain regions associated with speech and motor functions, coupled with impaired functional connectivity between these regions. The cortico-basal ganglia-thalamo-cortical system governs the dynamic interplay between cortical regions, with SMA as a key cortical site. It is hypothesized that the aberrant resting state functional connectivity will impact the language planning and motor execution necessary for fluent speech. Examining resting-state metrics as biomarkers could further elucidate the neural underpinnings of stuttering and guide intervention.

7.
Sci Rep ; 13(1): 20213, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980441

RESUMO

Several vaccines have been developed against SARS-CoV-2 and subsequently approved by national/international regulators. Detecting specific antibodies after vaccination enables us to evaluate the vaccine's effectiveness. We conducted a prospective longitudinal study among members of Tarbiat Modares University of Tehran, Iran, from 4 September 2021 until 29 December 2021. We aimed to compare the humoral immunogenicity of 3 vaccine types. Participants consisted of 462 adults. Anti-SARS-CoV-2 receptor-binding domain [RBD] IgG titer was compared in 3 groups, each vaccinated by available vaccines in Iran at the time: Oxford/AstraZeneca, COVIran Barekat, and Sinopharm. The median IgG titer was: 91.2, 105.6, 224.0 BAU/ml for Sinopharm, COVIran Barekat and Oxford/AstraZeneca respectively after the first dose; 195.2, 192.0, 337.6 BAU/ml after the second one. We also analyzed the frequency of antibody presence in each vaccine group, in the same order the results were 59.0%, 62.6% and 89.4% after the first dose and 92.1%,89.5% and 98.9% after the second. The comparison of results demonstrated that AstraZeneca vaccine is a superior candidate vaccine for COVID-19 vaccination out of the three. Our data also demonstrated statistically significant higher antibody titer among recipients with an infection history.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Estudos Longitudinais , Estudos Prospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Vacinação , Anticorpos Antivirais , Imunoglobulina G , Imunogenicidade da Vacina
8.
Brain Res Bull ; 202: 110727, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37562517

RESUMO

Psychiatric disorders are common in patients with allergic asthma, and they can have a significant impact on their quality of life and disease control. Recent studies have suggested that there may be potential immune-brain communication mechanisms in asthma, which can activate inflammatory responses in different brain areas, leading to structural and functional alterations and behavioral changes. However, the precise mechanisms underlying these alterations remain unclear. In this paper, we comprehensively review the relevant research on asthma-induced brain structural and functional alterations that lead to the initiation and promotion of anxiety. We summarize the possible pathways for peripheral inflammation to affect the brain's structure and function. Our review highlights the importance of addressing neuropsychiatric disorders in the clinical guidelines of asthma, to improve the quality of life of these patients. We suggest that a better understanding of the mechanisms underlying psychiatric comorbidities in asthma could lead to the development of more effective treatments for these patients.


Assuntos
Asma , Qualidade de Vida , Humanos , Ansiedade , Transtornos de Ansiedade , Encéfalo
9.
Respir Physiol Neurobiol ; 315: 104121, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37473791

RESUMO

Brain functional deficits have been reported in asthma patients which can result in behavioral disorders like depression and anxiety. These deficits may be associated with factors like resistance to treatment, incorrect self-evaluation, and inadequate self-control. However, changes in the brain volume in allergic asthma and the effects of inhaled corticosteroids, the most common anti-inflammatory agents for asthma treatment, on these alterations remain largely unclear. Here, we evaluated depression and anxiety-like behavior as well as volume changes in different brain area, using magnetic resonance imaging in an animal model of allergic asthma with pretreatment of inhaled fluticasone propionate. Asthma-induced behavioral changes were partially, but not completely, prevented by pretreatment with inhaled fluticasone propionate. Volumetry findings showed that the allergen decreased volumes of the corpus callosum and subcortical white matter, as well as the septal region and hippocampus (especially CA1 and fimbria). However, volumes of neocortex, insular, and anterior cingulate cortex increased in asthmatic rats compared to controls. Namely, pretreatment with inhaled fluticasone propionate partially prevented asthma-induced brain volume changes, but not completely. These findings suggest that asthma is associated with structural alterations in the brain, which may contribute to the induction of psychological disorders. Thus, considering brain changes in the clinical assessments could have important implications for asthma treatment.


Assuntos
Antiasmáticos , Asma , Animais , Ratos , Depressão/diagnóstico por imagem , Depressão/tratamento farmacológico , Androstadienos/uso terapêutico , Administração por Inalação , Asma/diagnóstico por imagem , Asma/tratamento farmacológico , Fluticasona/uso terapêutico , Corticosteroides/uso terapêutico , Encéfalo/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Ansiedade/tratamento farmacológico
10.
Neuroscience ; 524: 21-36, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37286161

RESUMO

Allergic asthma is a common chronic inflammatory condition associated with psychiatric comorbidities. Notably depression, correlated with adverse outcomes in asthmatic patients. Peripheral inflammation's role in depression has been shown previously. However, evidence regarding the effects of allergic asthma on the medial prefrontal cortex (mPFC)-ventral hippocampus (vHipp) interactions, an important neurocircuitry in affective regulation, is yet to be demonstrated. Herein, we investigated the effects of allergen exposure in sensitized rats on the immunoreactivity of glial cells, depression-like behavior, brain regions volume, as well as activity and connectivity of the mPFC-vHipp circuit. We found that allergen-induced depressive-like behavior was associated with more activated microglia and astrocytes in mPFC and vHipp, as well as reduced hippocampus volume. Intriguingly, depressive-like behavior was negatively correlated with mPFC and hippocampus volumes in the allergen-exposed group. Moreover, mPFC and vHipp activity were altered in asthmatic animals. Allergen disrupted the strength and direction of functional connectivity in the mPFC-vHipp circuit so that, unlike normal conditions, mPFC causes and modulates vHipp activity. Our results provide new insight into the underlying mechanism of allergic inflammation-induced psychiatric disorders, aiming to develop new interventions and therapeutic approaches for improving asthma complications.


Assuntos
Asma , Depressão , Ratos , Animais , Masculino , Alérgenos , Hipocampo , Córtex Pré-Frontal , Inflamação
11.
Respir Physiol Neurobiol ; 314: 104072, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37182593

RESUMO

Asthma is a heterogeneous disease in which the complexity of the breathing pattern reduces as the severity of the disease increases. Since the pathophysiological basis of reduced breathing pattern complexity in asthma is unclear, in this study, we investigated the effect of reducing inflammation using an inhaled corticosteroid (fluticasone propionate) on the breathing pattern of a rat model of asthma. Detrended fluctuation analysis, sample entropy, and cross-sample entropy analysis of both inter-breath interval and respiratory volume time series showed that early treatment with inhaled corticosteroids not only diminishes lung inflammation and airway hyper-responsiveness, but also has a protective effect against the reduction of breathing pattern complexity due to asthma. However, late treatment had a partial effect on asthma-induced respiratory pattern changes. Since inflammation is a key factor in shifting breathing dynamics away from normal fluctuations, these findings further emphasize the importance of early treatment of asthma with corticosteroids.


Assuntos
Asma , Pneumonia , Ratos , Animais , Administração por Inalação , Asma/tratamento farmacológico , Fluticasona/uso terapêutico , Corticosteroides/uso terapêutico , Inflamação/tratamento farmacológico , Pneumonia/tratamento farmacológico , Respiração
12.
Sci Rep ; 13(1): 6520, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37085688

RESUMO

Pharmacoresistant temporal lobe epilepsy affects millions of people around the world with uncontrolled seizures and comorbidities, like anxiety, being the most problematic aspects calling for novel therapies. The intrahippocampal kainic acid model of temporal lobe epilepsy is an appropriate rodent model to evaluate the effects of novel interventions, including glycolysis inhibition, on epilepsy-induced alterations. Here, we investigated kainic acid-induced changes in the dorsal hippocampus (dHPC) and basolateral amygdala (BLA) circuit and the efficiency of a glycolysis inhibitor, 2-deoxy D-glucose (2-DG), in resetting such alterations using simultaneous local field potentials (LFP) recording and elevated zero-maze test. dHPC theta and gamma powers were lower in epileptic groups, both in the baseline and anxiogenic conditions. BLA theta power was higher in baseline condition while it was lower in anxiogenic condition in epileptic animals and 2-DG could reverse it. dHPC-BLA coherence was altered only in anxiogenic condition and 2-DG could reverse it only in gamma frequency. This coherence was significantly correlated with the time in which the animals exposed themselves to the anxiogenic condition. Further, theta-gamma phase-locking was lower in epileptic groups in the dHPC-BLA circuit and 2-DG could considerably increase it.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Epilepsia do Lobo Temporal , Epilepsia , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Ácido Caínico , Ansiedade , Hipocampo , Epilepsia/induzido quimicamente , Glicólise
13.
Hippocampus ; 33(7): 880-885, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36864704

RESUMO

Mechanical ventilation (MV), as a life-saving procedure in critical patients, is a risk factor to develop of neurocognitive dysfunction and triggers of inflammation and apoptosis in the brain. Since diversion of breathing route to the tracheal tube diminishes brain activity entrained by physiological nasal breathing, we hypothesized that simulating nasal breathing using rhythmic air-puff (AP) into the nasal cavity of mechanically ventilated rats can reduce hippocampal inflammation and apoptosis in association with restoring respiration-coupled oscillations. We found that stimulating olfactory epithelium through applying rhythmic nasal AP, in association with reviving respiration-coupled brain rhythm, mitigates MV-induced hippocampal apoptosis and inflammation involving microglia and astrocytes. The current translational study opens a window for a novel therapeutic approach to reduce neurological complications induced by MV.


Assuntos
Hipocampo , Respiração Artificial , Ratos , Animais , Hipocampo/fisiologia , Inflamação , Mucosa Olfatória , Apoptose
14.
Life Sci ; 315: 121373, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621536

RESUMO

AIMS: Allergic asthma is associated with anxiety-related behaviors, leading to poor quality of life. Previous studies mainly described the neuropathophysiology of asthma-induced anxiety. However, the effects of corticosteroids, the most common anti-inflammatory agents for asthma treatment, on the neurophysiological foundations of allergic asthma-induced anxiety are unexplored. MAIN METHODS: Here, we evaluated lung and brain inflammation as well as anxiety in an animal model of allergic asthma pretreated with inhaled fluticasone propionate. Furthermore, to define the neurophysiological bases of these conditions, we studied the medial prefrontal cortex (mPFC)-amygdala circuit, which is previously shown to accompany asthma-induced anxiety. KEY FINDINGS: Our data showed that allergen induces anxiety, mPFC and amygdala inflammation, as well as disruptions in the local and long-range oscillatory activities within the mPFC-amygdala circuit. Interestingly, we observed a roughly consistent trend of changes with inhaled fluticasone pretreatment. Namely, the asthma-induced behavioral, inflammatory, and neurophysiological changes were partly, but not totally, prevented by inhaled fluticasone pretreatment. SIGNIFICANCE: We suggest that early treatment of asthmatic patients with inhaled corticosteroids improves mPFC-amygdala circuit function by attenuating neuroinflammation leading to reduced anxiety. These findings could lead clinical guidelines of asthma to consider the neuropsychiatric disorders of patients in treatment recommendations.


Assuntos
Asma , Qualidade de Vida , Animais , Androstadienos/efeitos adversos , Asma/induzido quimicamente , Fluticasona/uso terapêutico , Córtex Pré-Frontal , Ansiedade/tratamento farmacológico , Tonsila do Cerebelo , Corticosteroides/uso terapêutico , Administração por Inalação
15.
Int J Neurosci ; 133(5): 496-504, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-33998961

RESUMO

Aim: Low frequency stimulation (LFS) inhibits neuronal hyperexcitability following epileptic activity. However, knowledge about LFS' inhibitory mechanisms is lacking. Here, α1 and α2 adrenergic receptors' roles in mediating LFS inhibitory action on high-K+ induced epileptiform activity (EA) was examined in rat hippocampal slices.Materials and methods: LFS (1 Hz, 900 pulses) was applied to the Schaffer collaterals. Whole-cell, patch clamp recording was used to measure changes in CA1 pyramidal neurons' excitability. By applying high-K+ on hippocampal slices, EA was induced, and neuronal excitability increased.Results: When administered at the beginning of EA, LFS reduced neuronal excitability. In the presence of prazosin (10 µM, an α1 adrenergic receptor antagonist) and yohimbine (5 µM, an α2 adrenergic receptor antagonist), LFS' typically has a restorative impact on EA-induced membrane potential hyperpolarization and spike firing frequency, but this effect was reduced after high-K+ washout; These antagonists did not have a significant effect on LFS' inhibitory action on spike firing during EA.Conclusion: These findings suggest that LFS' anticonvulsant effect, on neuronal hyperexcitability following high-K+ EA, may be mediated partly through α adrenergic receptors in hippocampal slices.


Assuntos
Epilepsia , Receptores Adrenérgicos alfa , Ratos , Animais , Ratos Wistar , Hipocampo , Epilepsia/terapia , Receptores Adrenérgicos alfa 2 , Antagonistas Adrenérgicos/farmacologia , Estimulação Elétrica
16.
Respir Physiol Neurobiol ; 307: 103981, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36330894

RESUMO

BACKGROUND AND OBJECTIVES: Default mode network (DMN) is a principal network that is more active at the baseline functional state of consciousness and spontaneous brain activity. Nasal breathing beyond the oxygen supply, entrained brain oscillations in widespread brain regions. Consistent with the important role of nasal breathing on neural oscillation for brain function, here we aimed to evaluate respiration entrained DMN rhythms. MATERIALS AND METHODS: Using electroencephalography (EEG), we assessed the power spectral density and connectivity in DMN during the resting state among a group of sixteen healthy during three successive sessions. In addition to DMN, synchrony of the signal over the widespread cortical regions including somatosensory areas was investigated. Signal acquisition sessions consist of three times including nasal breathing, oral breathing, and nasal air-puff state that odorless air was puffed using a nasal cannula via an electrical valve (open duration of 630 ms) with a frequency of 0.2 Hz while subjects spontaneously breath orally. RESULTS: Our analyses demonstrated that nasal airflow, during both nasal breathing and nasal air-puff states, enhanced the power and connectivity of DMN regions specially at higher frequency bands, particularly gamma ranges. Enhancement in brain areas activity and connectivity including DMN and somatosensory due to the nasal airflow were not affected even in the condition that subjects were not attending to the nasal air-puff. CONCLUSIONS: Nasal airflow promotes brain oscillations, particularly at the range of gamma that is very essential for higher brain functions.


Assuntos
Rede de Modo Padrão , Eletroencefalografia , Humanos , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estado de Consciência , Imageamento por Ressonância Magnética
17.
Epilepsy Res ; 189: 107073, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36584482

RESUMO

Dopamine may be involved in the anticonvulsant action of deep brain stimulation (DBS). Therefore, ventral tegmental area (VTA), as a brain dopaminergic nucleus, may be a suitable target for DBS anticonvulsant action. This study investigated the effect of tonic and phasic stimulations of the VTA on seizure parameters. Seizures were induced in adult mice by sequential injections of a sub-convulsive dose of 35 mg/kg pentylenetetrazole (PTZ) every 48 h to develop the chemical kindling until the mice reached full kindled state (showing three consecutive seizure stages 4 or 5). Fully kindled mice received DBS once a day as tonic (square waves at 1 Hz; pulse duration: 200 µs; intensity: 300 µA; 600 pulses in 10 min) or phasic (square waves at 100 Hz; pulse duration: 200 µs; intensity: 300 µA; 8 trains of 10 pulses at 1 min interval; 800 pulses in 10 min) stimulations applied into their VTA for 4 days. A single dose of PTZ was injected after each DBS. Simultaneously electrocorticography and video recordings were performed during the seizure for accuracy in seizure severity parameters detection. Tonic but not phasic stimulation significantly decreased the epileptiform discharge duration and the seizure behavioral parameters such as maximum seizure stage, stage 5 duration, seizure duration. In addition, focal to generalized seizure latency increased following VTA tonic stimulation. These data suggest that tonic (but not phasic) stimulation of VTA before PTZ injection on 4 test days had anticonvulsant effects on PTZ-kindled seizures.


Assuntos
Excitação Neurológica , Pentilenotetrazol , Humanos , Pentilenotetrazol/toxicidade , Anticonvulsivantes/uso terapêutico , Área Tegmentar Ventral , Convulsões/terapia , Convulsões/tratamento farmacológico
18.
Neurochem Res ; 48(1): 210-228, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36064822

RESUMO

Temporal lobe epilepsy is the most drug-resistant type with the highest incidence among the other focal epilepsies. Metabolic manipulations are of great interest among others, glycolysis inhibitors like 2-deoxy D-glucose (2-DG) being the most promising intervention. Here, we sought to investigate the effects of 2-DG treatment on cellular and circuit level electrophysiological properties using patch-clamp and local field potentials recordings and behavioral alterations such as depression and anxiety behaviors, and changes in nitric oxide signaling in the intrahippocampal kainic acid model. We found that epileptic animals were less anxious, more depressed, with more locomotion activity. Interestingly, by masking the effect of increased locomotor activity on the parameters of the zero-maze test, no altered anxiety behavior was noted in epileptic animals. However, 2-DG could partially reverse the behavioral changes induced by kainic acid. The findings also showed that 2-DG treatment partially suppresses cellular level alterations while failing to reverse circuit-level changes resulting from kainic acid injection. Analysis of NADPH-diaphorase positive neurons in the CA1 area of the hippocampus revealed that the number of positive neurons was significantly reduced in dorsal CA1 of the epileptic animals and 2-DG treatment did not affect the diminishing effect of kainic acid on NADPH-d+ neurons in the CA1 area. In the control group receiving 2-DG, however, an augmented NADPH-d+ cell number was noted. These data suggest that 2-DG cannot suppress epileptiform activity at the circuit-level in this model of epilepsy and therefore, may fail to control the seizures in temporal lobe epilepsy cases.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Animais , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/prevenção & controle , Ácido Caínico/toxicidade , NADPH Desidrogenase/metabolismo , NADPH Desidrogenase/farmacologia , Glucose/metabolismo , NADP/metabolismo , Hipocampo/metabolismo , Epilepsia/metabolismo , Neurônios/metabolismo , Desoxiglucose/farmacologia , Desoxiglucose/uso terapêutico , Glicólise , Modelos Animais de Doenças
19.
Int J Neurosci ; : 1-11, 2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36416718

RESUMO

Background Cognitive impairments are linked to poor treatment response and disease control in allergic asthma. However, there are no studies exploring attention-related functional brain alterations in allergic asthma. Here, we explore attention deficit and its association with clinical characteristics and common neuropsychiatric disorders in patients with allergic asthma.Methods We recruited 38 participants, equally distributed into healthy and asthma groups. Behavioral, neurophysiological, and lung function assessment tools were used in this study.Results Our behavioral data show that allergic asthma induces attention impairment. Additionally, the event-related potentials (ERP) analysis reveals that this attention deficit is associated with a disruption in cognitive processing capability in frontal brain areas. These behavioral and neurophysiological abnormalities were strongly correlated with disease severity and neuropsychiatric comorbidities of asthmatic patients.Conclusion Together, here we propose that disrupted neurophysiological responses in frontal brain areas might lead to attention impairments in patients with allergic asthma. These findings could help characterizing the neuro-pathophysiology of cognitive disorders in allergic asthma, possibly opening the way for development of novel treatment strategies.

20.
Epilepsy Res ; 188: 107055, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36423428

RESUMO

Low frequency deep brain electrical stimulation (LFS) is a potential therapeutic strategy to control seizures in epilepsy patients. Given the functional connection of the olfactory bulb with the hippocampal formation, in this study the effect of applying LFS in the olfactory bulb on seizure severity, and learning and memory was investigated in hippocampal kindling. In male Wistar rats (250-300 g), a tripolar electrode was inserted in the CA1 region of the right hippocampus to apply kindling stimulations and record the afterdischarges (ADs). Two bipolar electrodes were also inserted bilaterally into the olfactory bulbs for applying LFS. In the kindled group, the animals received daily kindling stimulations to produce stage 5 seizures for three consecutive days. In one group of subjects, LFS was administered 2-3 min after the last kindling stimulation. Within this group, subjects were divided into two subgroups: one subgroup received two and the other subgroup received four packages of LFS protocol. Obtained data showed that bilateral LFS application to the left and right olfactory bulb reduced seizure severity. Among the protocols, applying four packages of LFS had a greater anticonvulsant effect compared to applying two packages LFS. Applying LFS in the olfactory bulb of kindled subject restored performance on measures that test short- and long-term memory - the Y maze and Morris water maze test - and applying four packages of LFS was more effective than two. These results indicated that applying LFS to the olfactory bulb had anticonvulsant effects and ameliorated the seizure-induced impairment of working and spatial memory. These effects appear to be depended on the number of applied LFS and were greater by increasing the number of LFS.


Assuntos
Anticonvulsivantes , Bulbo Olfatório , Masculino , Ratos , Animais , Ratos Wistar , Convulsões/terapia , Memória Espacial
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