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1.
J Physiol ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39243394

RESUMO

Paired vagus nerve stimulation (VNS) has emerged as a promising strategy to potentiate recovery after neurological injury. This approach, which combines short bursts of electrical stimulation of the vagus nerve with rehabilitation exercises, received approval from the US Food and Drug Aministration in 2021 as the first neuromodulation-based therapy for chronic stroke. Because this treatment is increasingly implemented in clinical practice, there is a need to take stock of what we know about this approach and what we have yet to learn. Here, we provide a survey on the foundational basis of VNS therapy for stroke and offer insight into the mechanisms that underlie potentiated recovery, focusing on the principles of neuromodulatory reinforcement. We discuss the current state of observations regarding synaptic reorganization in motor networks that are enhanced by VNS, and we propose other prospective loci of neuromodulation that should be evaluated in the future. Finally, we highlight the future opportunities and challenges to be faced as this approach is increasingly translated to clinical use. Collectively, a clearer understanding of the mechanistic basis of VNS therapy may reveal ways to maximize its benefits.

2.
Neurochem Int ; : 105842, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39244038

RESUMO

Several evidence suggest that immuno-inflammatory responses are involved in the pathogenesis of anorexia nervosa (AN). Herein we investigate the possible alteration of key mediators of inflammation, redox balance, and neuroplasticity in the brain of rats showing an anorexic-like phenotype. We modeled AN in adolescent female rats using the activity-based anorexia (ABA) paradigm and measured gene expression levels of targets of interest in the prefrontal cortex (PFC) and dorsal hippocampus (DH). We observed reduced mRNA levels of pro-inflammatory cytokines IL-1ß and TNF-α, the inflammasome NLRP3, and the microglial marker CD11b in both PFC and DH of ABA animals. Conversely, the mRNA of IL-6, which acts as both a pro-inflammatory and anti-inflammatory cytokine, was increased. Moreover, we observed an overall upregulation of different antioxidant enzymes in PFC, while their profile was not affected or opposite in the DH except for MT1α. Interestingly, ABA animals showed elevated levels of the neuroplasticity marker BDNF in both PFC and DH. Our data indicate that ABA induction is associated with anatomical-specific cerebral alteration of mediators of neuroinflammation, oxidative balance and neuroplasticity. Although more research should be conducted, these results add important information about the role of these systems in the complex of AN etiopathogenesis.

3.
Wiad Lek ; 77(7): 1311-1317, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39241127

RESUMO

OBJECTIVE: Aim: The objective of the research was to conduct a comprehensive longitudinal analysis of the temporal dynamics of glutathione system functionality in individuals diagnosed with paranoid schizophrenia. Specifically, the research was focused on investigating variations in the profiles of glutathione-dependent enzymes, with meticulous consideration given to the duration of the illness. PATIENTS AND METHODS: Materials and Methods: The study group comprised 300 individuals officially diagnosed with 'Paranoid Schizophrenia,' subdivided into five subgroups, each consisting of 60 patients. The subgroups were defined as follows: Subgroup I included 60 patients with a disease duration ranging from 3 to 5 years; Subgroup II comprised 60 patients with a duration of 6 to 10 years; Subgroup III consisted of 60 patients with a duration of 11 to 15 years; Subgroup IV included 60 patients with a duration of 16 to 20 years; and Subgroup V encompassed 60 patients with a duration of 21 years and older. The comparison group comprised 20 patients diagnosed with "Primary psychotic episode". RESULTS: Results: The research demonstrates a consistent and noteworthy reduction in the enzymatic activities of glutathione peroxidase, glutathione reductase, and glutathione-S-transferase in various Subgroups of paranoid schizophrenia patients. The observed declines are particularly prominent within the first 3-5 years of the illness, show casing statistically significant reductions. Patients with prolonged illness durations, especially surpassing 21 years, display substantial reductions in all three enzymes, suggesting a cumulative enzymatic impact associated with prolonged illness. CONCLUSION: Conclusions: The identification of critical periods of inhibition in the glutathione protection chain, provides valuable information about potential therapeutic interventions for individuals with paranoid schizophrenia.


Assuntos
Esquizofrenia Paranoide , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Redutase/sangue , Glutationa Transferase/metabolismo , Adulto Jovem , Estudos Longitudinais , Fatores de Tempo , Glutationa/metabolismo
4.
Front Pharmacol ; 15: 1426769, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39253375

RESUMO

Depression, a mood disorder characterized by a persistent low mood and lack of enjoyment, is considered the leading cause of non-fatal health losses worldwide. Neuroplasticity refers to the brain's ability to adapt to external or internal stimuli, resulting in functional and structural changes. This process plays a crucial role in the development of depression. Traditional Chinese Medicine (TCM) shows significant potential as a complementary and alternative therapy for neurological diseases, including depression. However, there has been no systematic summary of the role of neuroplasticity in the pathological development of depression and TCM Interventions currently. This review systematically summarized recent literature on changes in neuroplasticity in depression and analyzed the regulatory mechanisms of active metabolites in TCM and TCM formulas on neuroplasticity in antidepressant treatment. Additionally, this review discussed the limitations of current research and the application prospects of TCM in regulating neuroplasticity in antidepressant research.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39254835

RESUMO

The persistent use of opioids leads to profound changes in neuroplasticity of the brain, contributing to the emergence and persistence of addiction. However, chronic opioid use disrupts the delicate balance of the reward system in the brain, leading to neuroadaptations that underlie addiction. Chronic cocaine usage leads to synchronized alterations in gene expression, causing modifications in the Nucleus Accumbens (NAc), a vital part of the reward system of the brain. These modifications assist in the development of maladaptive behaviors that resemble addiction. Neuroplasticity in the context of addiction involves changes in synaptic connectivity, neuronal morphology, and molecular signaling pathways. Drug-evoked neuroplasticity in opioid addiction and withdrawal represents a complicated interaction between environmental, genetic, and epigenetic factors. Identifying specific transcriptional and epigenetic targets that can be modulated to restore normal neuroplasticity without disrupting essential physiological processes is a critical consideration. The discussion in this article focuses on the transcriptional aspects of drug-evoked neuroplasticity, emphasizing the role of key transcription factors, including cAMP response element-binding protein (CREB), ΔFosB, NF-kB, Myocyte-enhancing factor 2 (MEF2), Methyl-CpG binding protein 2 (MeCP2), E2F3a, and FOXO3a. These factors regulate gene expression and lead to the neuroadaptive changes observed in addiction and withdrawal. Epigenetic regulation, which involves modifying gene accessibility by controlling these structures, has been identified as a critical component of addiction development. By unraveling these complex molecular processes, this study provides valuable insights that may pave the way for future therapeutic interventions targeting the mechanisms underlying addiction and withdrawal.

6.
Behav Brain Res ; 476: 115235, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236931

RESUMO

BACKGROUND: Alzheimer's disease (AD) is linked to the accumulation of Aß, increased tau hyperphosphorylation, persistent neuroinflammation, and a decline in neurotrophic factors, neurogenesis, and synaptic plasticity. Oxytocin (OT) has a significant impact on memory and learning. We examined the influence of intranasal (IN) OT on synaptic plasticity, neurogenesis, histone acetylation, and spatial and cognitive memories in rats. METHODS: Aß25-35 (5 µg/2.5 µl) was administered bilaterally in the CA1 of male Wistar rats for four consecutive days. After seven days of recovery, OT (2 µg/µl, 10 µl in each nostril) was administered IN for seven consecutive days. Working, spatial, and cognitive memories, and gene expression of neurogenesis- and synaptic plasticity-involved factors were measured in the hippocampus. Histone acetylation (H3K9 and H4K8) was also measured using western blotting. RESULTS: IN administration of OT significantly improved working and spatial memory impairment induced by Aß and increased the factors involved in synaptic plasticity (MeCP2, REST, synaptophysin, and BDNF) and neurogenesis (Ki67 and DCX). We also found an enhancement in the levels of H3K9ac and H4K8ac following OT administration. CONCLUSION: These findings indicated that IN OT could improve hippocampus-related behaviors by increasing synaptic plasticity, stimulating neurogenesis, and chromatin plasticity.

7.
Artigo em Russo | MEDLINE | ID: mdl-39248584

RESUMO

OBJECTIVE: To assess the severity of the phantom pain syndrome in patients with consequences of combat trauma before and after comprehensive therapy using the bioacoustic correction (BAC) method. MATERIAL AND METHODS: A number of male patients equal 15 aged 24-60 years with consequences of combat traumas and confirmed phantom pain syndrome were examined. Patients were given 10 BAC therapy procedures with an average duration of 20 minutes per day after a comprehensive diagnostic assessment of state. The dynamics of pain syndrome was evaluated by visual analogue scale. RESULTS: It has been shown that the BAC procedures contribute to a significant reduction of the phantom pain syndrome severity. The decrease of the phantom pain syndrome after the BAC procedures was maintained at least 6 months in the catamnesis. The probable mechanism of reducing the phantom pain syndrome in BAC procedures is adaptive reorganization of thalamocortical detectors of affected limbs by modulation of neuroplasticity processes. CONCLUSION: The conducted preliminary studies have shown that the BAC therapy contributes to the reduction of the phantom pain syndrome intensity.


Assuntos
Membro Fantasma , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Projetos Piloto , Membro Fantasma/terapia , Medição da Dor/métodos , Adulto Jovem
8.
Early Hum Dev ; 198: 106111, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39244966

RESUMO

BACKGROUND: It is unknown whether ultra-early physiotherapy commenced during neonatal intensive care unit admission is of value for optimising developmental outcomes in preterm/term infants at high-risk of cerebral palsy or motor-delay. AIMS: To determine whether ultra-early parent-administered physiotherapy to preterm/term high- risk infants commenced at earliest from 34-weeks post menstrual age, improves motor outcomes at 16-weeks corrected age (CA) compared to usual care. METHODS: Single-blind randomised controlled pilot study with 30 infant participants. The primary outcome was the Alberta Infant Motor Scale (AIMS) total score at 16-weeks CA. Secondary outcomes included (i) parent Depression Anxiety and Stress Score and Parent Perceptions Survey at 16-weeks CA; and (ii) Bayley Scales of Infant Development at 12-months CA. RESULTS: There were no clinically worthwhile effects at 16-weeks CA on the AIMS (mean between-group difference, 95% CI: -0.2, -2.4 to 2.0) or most secondary outcomes. However, the parents' "perception of treatment effectiveness" and "perception of change" favoured the experimental group. CONCLUSIONS: In this pilot trial, there was no clinically worthwhile effect of ultra-early parent-administered physiotherapy over usual care on the AIMS. However, the intervention was feasible for infants, acceptable to parents and parents perceived a benefit of treatment. Whilst this trial did not demonstrate treatment effectiveness using the AIMS, these findings should be interpreted cautiously because of the small sample size, the low responsivity of the AIMS to change in motor performance and the heterogeneity of the participants. Therefore, the intervention should not be abandoned on the basis of this trial, but rather further evaluated in a larger trial that addresses some of the learnings from this one.

9.
Neuroscience ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245312

RESUMO

Ketamine is a widely used clinical drug that has several functional and clinical applications, including its use as an anaesthetic, analgesic, anti-depressive, anti-suicidal agent, among others. Among its diverse behavioral effects, it influences short-term memory and induces psychedelic effects. At the neural level across different brain areas, it modulates neural firing rates, neural tuning, brain oscillations, and modularity, while promoting hypersynchrony and random connectivity between neurons. In our recent studies we demonstrated that topical application of ketamine on the visual cortex alters neural tuning and promotes vigorous connectivity between neurons by decreasing their firing variability. Here, we begin with a brief review of the literature, followed by results from our lab, where we synthesize a dendritic model of neural tuning and network changes following ketamine application. This model has potential implications for focused modulation of cortical networks in clinical settings. Finally, we identify current gaps in research and suggest directions for future studies, particularly emphasizing the need for more animal experiments to establish a platform for effective translation and synergistic therapies combining ketamine with other protocols such as training and adaptation. In summary, investigating ketamine's broader systemic effects, not only provides deeper insight into cognitive functions and consciousness but also paves the way to advance therapies for neuropsychiatric disorders.

10.
Scand J Med Sci Sports ; 34(9): e14725, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39245921

RESUMO

The relationship between structural changes in the cerebral gray matter and diminished balance control performance in patients with chronic ankle instability (CAI) has remained unclear. This paper aimed to assess the difference in gray matter volume (GMV) between participants with CAI and healthy controls (HC) and to characterize the role of GMV in the relationship between disease duration and balance performance in CAI. 42 participants with CAI and 33 HC completed the structural brain MRI scans, one-legged standing test, and Y-balance test. Regional GMV was measured by applying voxel-based morphometry methods. The result showed that, compared with HC, participants with CAI exhibited lower GMV in multiple brain regions (familywise error [FWE] corrected p < 0.021). Within CAI only, but not in HC, lower GMV in the thalamus (ß = -0.53, p = 0.003) and hippocampus (ß = -0.57, p = 0.001) was associated with faster sway velocity of the center of pressure (CoP) in eyes closed condition (i.e., worse balance control performance). The GMV in the thalamus (percentage mediated [PM] = 32.02%; indirect effect ß = 0.119, 95% CI = 0.003 to 0.282) and hippocampus (PM = 33.71%; indirect effect ß = 0.122, 95% CI = 0.005 to 0.278) significantly mediated the association between the disease duration and balance performance. These findings suggest that the structural characteristics of the supraspinal elements is critical to the maintenance of balance control performance in individuals suffering from CAI, which deserve careful consideration in the management and rehabilitation programs in this population.


Assuntos
Articulação do Tornozelo , Substância Cinzenta , Instabilidade Articular , Imageamento por Ressonância Magnética , Equilíbrio Postural , Humanos , Equilíbrio Postural/fisiologia , Masculino , Instabilidade Articular/fisiopatologia , Instabilidade Articular/diagnóstico por imagem , Feminino , Adulto Jovem , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Articulação do Tornozelo/patologia , Estudos de Casos e Controles , Adulto , Doença Crônica , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tálamo/fisiopatologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Fatores de Tempo
11.
Front Hum Neurosci ; 18: 1432830, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39257696

RESUMO

Introduction: In past work we demonstrated different patterns of white matter (WM) plasticity in females versus males associated with learning a lab-based unilateral motor skill. However, this work was completed in neurologically intact older adults. The current manuscript sought to replicate and expand upon these WM findings in two ways: (1) we investigated biological sex differences in neurologically intact young adults, and (2) participants learned a dynamic full-body balance task. Methods: 24 participants (14 female, 10 male) participated in the balance training intervention, and 28 were matched controls (16 female, 12 male). Correlational tractography was used to analyze changes in WM from pre- to post-training. Results: Both females and males demonstrated skill acquisition, yet there were significant differences in measures of WM between females and males. These data support a growing body of evidence suggesting that females exhibit increased WM neuroplasticity changes relative to males despite comparable changes in motor behavior (e.g., balance). Discussion: The biological sex differences reported here may represent an important factor to consider in both basic research (e.g., collapsing across females and males) as well as future clinical studies of neuroplasticity associated with motor function (e.g., tailored rehabilitation approaches).

12.
Front Neurosci ; 18: 1434309, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224579

RESUMO

Grapheme-color synesthesia is a normal and healthy variation of human perception. It is characterized by the association of letters or numbers with color perceptions. The etiology of synesthesia is not yet fully understood. Theories include hyperconnectivity in the brain, cross-activation of adjacent or functionally proximate sensory areas of the brain, or various models of lack of inhibitory function in the brain. The growth factor brain-derived neurotrophic (BDNF) plays an important role in the development of neurons, neuronal pathways, and synapses, as well as in the protection of existing neurons in both the central and peripheral nervous systems. ELISA methods were used to compare BDNF serum concentrations between healthy test subjects with and without grapheme-color synesthesia to establish a connection between concentration and the occurrence of synesthesia. The results showed that grapheme-color synesthetes had an increased BDNF serum level compared to the matched control group. Increased levels of BDNF can enhance the brain's ability to adapt to changing environmental conditions, injuries, or experiences, resulting in positive effects. It is discussed whether the integration of sensory information is associated with or results from increased neuroplasticity. The parallels between neurodegeneration and brain regeneration lead to the conclusion that synesthesia, in the sense of an advanced state of consciousness, is in some cases a more differentiated development of the brain rather than a relic of early childhood.

13.
Biosci Rep ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39230890

RESUMO

Myelination of axons is a key determinant of fast action potential propagation, axonal health and circuit function. Previously considered a static structure, it is now clear that myelin is dynamically regulated in response to neuronal activity in the CNS. However, how activity-dependent signals are conveyed to oligodendrocytes remains unclear. Here we review the potential mechanisms by which neurons could communicate changing activity levels to myelin, with a focus on the accumulating body of evidence to support activity-dependent vesicular signalling directly onto myelin sheaths. We discuss recent in vivo findings of activity-dependent fusion of neurotransmitter vesicles from non-synaptic axonal sites, and how modulation of this vesicular fusion regulates the stability and growth of myelin sheaths. We also consider the potential mechanisms by which myelin could sense and respond to axon-derived signals to initiate remodelling, and the relevance of these adaptations for circuit function. We propose that axonal vesicular signalling represents an important and underappreciated mode of communication by which neurons can transmit activity-regulated signals to myelinating oligodendrocytes and, potentially, more broadly to other cell types in the CNS.

14.
Neuroimage ; 298: 120785, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39154869

RESUMO

Working memory (WM) is an essential cognitive function that underpins various higher-order cognitive processes. Improving WM capacity through targeted training interventions has emergered as a potential approach for enhancing cognitive abilities. The present study employed an 8-week regimen of computerized WM training (WMT) to investigate its effect on neuroplasticity in healthy individuals, utilizing neuroimaging data gathered both before and after the training. The key metrics assessed included the amplitude of low-frequency fluctuations (ALFF), voxel-based morphometry (VBM), and the spatial distribution correlations of neurotransmitter. The results indicated that post-training, compared to baseline, there was a reduction in ALFF in the medial superior frontal gyrus and an elevation in ALFF in the left middle occipital gyrus within the training group. In comparison to the control group, the training group also exhibited decreased ALFF in the anterior cingulate cortex, angular gyrus, and superior parietal lobule, along with increased ALFF in the postcentral gyrus post-training. VBM analysis revealed a significant increase in gray matter volume (GMV) in the right dorsal superior frontal gyrus after the training period, compared to the initial baseline measurement. Furthermore, the training group showed GMV increases in the dorsal superior frontal gyrus, Rolandic operculum, precentral gyrus, and postcentral gyrus when compared to the control group. In addition, significant associations were identifed between neuroimaging measurements (AFLL and VBM) and the spatial patterns of neurotransmitters such as serotonin (5-HT), dopamine (DA), and N-methyl-D-aspartate (NMDA), providing insights into the underlying neurochemical processes. These findings clarify the neuroplastic changes caused by WMT, offering a deeper understanding of brain plasticity and highlighting the potential advantages of cognitive training interventions.


Assuntos
Imageamento por Ressonância Magnética , Memória de Curto Prazo , Plasticidade Neuronal , Humanos , Plasticidade Neuronal/fisiologia , Masculino , Memória de Curto Prazo/fisiologia , Feminino , Adulto , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Neurotransmissores/metabolismo , Neuroimagem/métodos , Treino Cognitivo
15.
Neuropharmacology ; 261: 110132, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39208980

RESUMO

Selective serotonin (5-HT) reuptake inhibitors (SSRIs) like fluoxetine remain a first-line treatment for major depression, but are effective in less than half of patients and can take 4-8 weeks to show results. In this study, we examined cF1ko mice with genetically induced upregulation of 5-HT1A autoreceptors that reduces 5-HT neuronal activity. These mice display anxiety- and depression-related behaviors that did not respond to chronic fluoxetine treatment. We examined treatment with NLX-101, a biased agonist that preferentially targets 5-HT1A heteroreceptors. By testing different doses of NLX-101, we found that a dose of 0.2 mg/kg was effective in reducing depression-related behavior in cF1ko mice without causing hypothermia, a 5-HT1A autoreceptor-mediated response. After 1 h, this dose activated dorsal raphe 5-HT neurons and cells in the medial prefrontal cortex (mPFC), increasing nuclear c-fos labelling in cF1ko mice. In cF1ko mice but not wild-type littermates, 0.2 mg/kg NLX-101 administered 1 h prior to each behavioral test for two weeks reduced depressive behavior in the forced swim test, but increased anxiety-related behaviors in the open field, elevated plus maze, and novelty suppressed feeding tests. During this treatment, NLX-101 induced widespread increases in the density of 5-HT axons, varicosities, and especially synaptic and triadic structures, particularly in depression-related brain regions including mPFC, hippocampal CA1 and CA2/3, amygdala and nucleus accumbens of cF1ko mice. Overall, NLX-101 was rapid and effective in reducing depressive behavior in SSRI-resistant mice, but also induced anxiety-related behaviors. The increase in serotonin innervation induced by intermittent NLX-101 may contribute to its behavioral actions.

16.
Acta Pharmacol Sin ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152295

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder characterized by cognitive impairments. Despite the limited efficacy of current treatments for AD, the 1,2,4-oxadiazole structure has garnered significant attention in medicinal chemistry due to its potential impact on mGluR1 and its association with AD therapy. In this study, a series of novel 1,2,4-oxadiazole derivatives were designed, synthesized, and evaluated for the neuroprotective effects in human neuroblastoma (SH-SY5Y) cells. Among all the derivatives tested, FO-4-15 (5f) existed the lowest cytotoxicity and the highest protective effect against H2O2. Based on these in vitro results, FO-4-15 was administered to 3×Tg mice and significantly improved the cognitive impairments of the AD mice. Pathological analysis showed that FO-4-15 significantly reduced Aß accumulation, Tau hyper-phosphorylation, and synaptic impairments in the 3×Tg mice. Dysfunction of the CaMKIIα/Fos signaling pathway in 3×Tg mice was found to be restored by FO-4-15 and the necessity of the CaMKIIα/Fos for FO-4-15 was subsequently confirmed by the use of a CaMKIIα inhibitor in vitro. Beyond that, mGluR1 was identified to be a potential target of FO-4-15, and the interaction of FO-4-15 and mGluR1 was displayed by Ca2+ flow increase, molecular docking, and interaction energy analysis. The target of FO-4-15 was further confirmed in vitro by JNJ16259685, a nonselective inhibitor of mGluR1. These findings suggest that FO-4-15 may hold promise as a potential treatment for Alzheimer's disease.

17.
Artigo em Inglês | MEDLINE | ID: mdl-39102007

RESUMO

Parkinson's disease (PD) is the second most frequent neurodegenerative disorder, affecting millions of people and rapidly increasing over the last decades. Even though there is no intervention yet to stop the neurodegenerative pathology, many efficient treatment methods are available, including for patients with advanced PD. Neuroplasticity is a fundamental property of the human brain to adapt both to external changes and internal insults and pathological processes. In this paper we examine the current knowledge and concepts concerning changes at network level, cellular level and molecular level as parts of the neuroplastic response to protein aggregation pathology, synapse loss and neuronal loss in PD. We analyse the beneficial, compensatory effects, such as augmentation of nigral neurons efficacy, as well as negative, maladaptive effects, such as levodopa-induced dyskinesia. Effects of physical activity and different treatments on neuroplasticity are considered and the opportunity of biomarkers identification and use is discussed.

18.
Sci Rep ; 14(1): 18632, 2024 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-39128924

RESUMO

LSD is a hallucinogen with complex neurobiological and behavioral effects. Underlying these effects are changes in brain neuroplasticity. This is the first study to follow the developmental changes in brain structure and function following LSD exposure in periadolescence. We hypothesized LSD given during a time of heightened neuroplasticity, particularly in the forebrain, would affect cognitive and emotional behavior and the associated underlying neuroanatomy and neurocircuitry. Female and male mice were given vehicle, single or multiple treatments of 3.3 µg of LSD by oral gavage starting on postnatal day 51. Between postnatal days 90-120 mice were imaged and tested for cognitive and motor behavior. MRI data from voxel-based morphometry, diffusion weighted imaging, and BOLD resting state functional connectivity were registered to a mouse 3D MRI atlas with 139 brain regions providing site-specific differences in global brain structure and functional connectivity between experimental groups. Motor behavior and cognitive performance were unaffected by periadolescent exposure to LSD. Differences across experimental groups in brain volume for any of the 139 brain areas were few in number and not focused on any specific brain region. Multiple exposures to LSD significantly altered gray matter microarchitecture across much of the brain. These changes were primary associated with the thalamus, sensory and motor cortices, and basal ganglia. The forebrain olfactory system and prefrontal cortex and hindbrain cerebellum and brainstem were unaffected. The functional connectivity between forebrain white matter tracts and sensorimotor cortices and hippocampus was reduced with multidose LSD exposure. Does exposure to LSD in late adolescence have lasting effects on brain development? The bulk of our significant findings were seen through changes is DWI values across 74 brain areas in the multi-dose LSD group. The pronounced changes in indices of anisotropy across much of the brain would suggest altered gray matter microarchitecture and neuroplasticity. There was no evidence of LSD having consequential effects on cognitive or motor behavior when animal were evaluated as young adults 90-120 days of age. Neither were there any differences in the volume of specific brain areas between experimental conditions. The reduction in connectivity in forebrain white matter tracts with multidose LSD and consolidation around sensorimotor and hippocampal brain areas requires a battery of tests to understand the consequences of these changes on behavior.


Assuntos
Encéfalo , Dietilamida do Ácido Lisérgico , Animais , Masculino , Feminino , Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Encéfalo/diagnóstico por imagem , Camundongos , Dietilamida do Ácido Lisérgico/farmacologia , Dietilamida do Ácido Lisérgico/administração & dosagem , Alucinógenos/administração & dosagem , Alucinógenos/farmacologia , Cognição/efeitos dos fármacos , Imageamento por Ressonância Magnética , Plasticidade Neuronal/efeitos dos fármacos , Administração Oral , Atividade Motora/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Substância Cinzenta/efeitos dos fármacos , Substância Cinzenta/crescimento & desenvolvimento , Substância Cinzenta/diagnóstico por imagem
19.
Pol J Radiol ; 89: e328-e335, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139257

RESUMO

Purpose: The aim of this study was to evaluate the effects of aerobic training on motor cortical areas in multiple sclerosis (MS) patients, based on task-based functional magnetic resonance imaging (t-fMRI) as well as on brain activity at rest, according to resting state functional MRI (rs-fMRI) studies. Material and methods: Multiple sclerosis patients were divided into 2 groups consisting of 14 participants each: the MS study group and the MS control group. All MS patients underwent clinical assessment and MRI examination, twice: in the MS study group at the time of inclusion in the study and after a 4-week period of aerobic training, whereas in the MS control group it happened at the time of inclusion and after a period of one month without exercise rehabilitation. The MRI study protocol included rs-fMRI and t-fMRI sequences, which were the grounds for an analysis of resting state networks (RSN) as well as peak level and cluster level parameters within motor cortex areas - the primary motor cortex, premotor area, and supplementary motor area, respectively. Results: In the MS study group, aerobic training improved the clinical condition and decreased the functional correlation between the sensorimotor network and the salience network. Also, significant decreases of the mean cluster level (72.42 vs. 38.35) and peak level values (10.89 vs. 7.64) were observed in the contralateral primary motor cortex in this group of patients between examinations. Conclusions: Aerobic training not only improves physical performance but also contributes to changes in brain activity - both within RSN and motor cortex areas in MS patients.

20.
Toxics ; 12(8)2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39195700

RESUMO

Repeated exposure to tobacco smoke causes neuroinflammation and neuroplasticity, which correlates with smoking withdrawal-induced anxiety. The purpose of this study was to investigate the anticipated involvement of antioxidant-rich nanoparticles (NPs) prepared by oxidation-triggered polymerization of green tea catechins in impacting these effects in a rat model of tobacco smoke exposure. Exposure to tobacco smoke was carried out for 2 h a day, 5 days a week, for a total of 36 days. Weekly behavioral tests were conducted prior to recommencing the exposure. Following a 20-day exposure period, rats were administered either distilled water or green tea (GT) NPs (20 mg/kg, orally) for an additional 16 days. Our findings revealed that tobacco smoke exposure induced anxiety-like behavior indicative of withdrawal, and this effect was alleviated by GT NPs. Tobacco smoke exposure caused a marked increase in the relative mRNA and protein expression of nuclear factor-kappa B (NF-κB) and reduced the relative mRNA and protein expression of brain-derived neurotrophic factor (BDNF) in the hippocampus (HIP) and hypothalamus (HYP) brain subregions. The intervention of GT NPs effectively inhibited these effects. Our findings demonstrate the potent protective role of GT NPs in reducing withdrawal-induced anxiety-like behavior, neuroinflammation, and neuroplasticity triggered by tobacco smoke exposure.

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