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1.
BMC Res Notes ; 17(1): 143, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773625

RESUMO

OBJECTIVES: The G72 mouse model of schizophrenia represents a well-known model that was generated to meet the main translational criteria of isomorphism, homology and predictability of schizophrenia to a maximum extent. In order to get a more detailed view of the complex etiopathogenesis of schizophrenia, whole genome transcriptome studies turn out to be indispensable. Here we carried out microarray data collection based on RNA extracted from the retrosplenial cortex, hippocampus and thalamus of G72 transgenic and wild-type control mice. Experimental animals were age-matched and importantly, both sexes were considered separately. DATA DESCRIPTION: The isolated RNA from all three brain regions was purified, quantified und quality controlled before initiation of the hybridization procedure with SurePrint G3 Mouse Gene Expression v2 8  ×  60 K microarrays. Following immunofluorescent measurement und preprocessing of image data, raw transcriptome data from G72 mice and control animals were extracted and uploaded in a public database. Our data allow insight into significant alterations in gene transcript levels in G72 mice and enable the reader/user to perform further complex analyses to identify potential age-, sex- and brain-region-specific alterations in transcription profiles and related pathways. The latter could facilitate biomarker identification and drug research and development in schizophrenia research.


Assuntos
Córtex Cerebral , Modelos Animais de Doenças , Hipocampo , Esquizofrenia , Tálamo , Transcriptoma , Animais , Esquizofrenia/genética , Esquizofrenia/metabolismo , Hipocampo/metabolismo , Masculino , Feminino , Camundongos , Transcriptoma/genética , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Tálamo/metabolismo , Camundongos Transgênicos , Perfilação da Expressão Gênica/métodos , Fatores Sexuais
2.
Neurology ; 102(10): e209326, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669634

RESUMO

BACKGROUND AND OBJECTIVES: Narcolepsy type 1 (NT1) is due to the loss of hypothalamic neurons that produce orexin (ORX), by a suspected immune-mediated process. Rare postmortem studies are available and failed to detect any inflammation in the hypothalamic region, but these brains were collected years after the first symptoms. In vivo studies close to disease onset are lacking. We aimed to explore microglia density in the hypothalamus and thalamus in NT1 compared with controls using [18F]DPA-714 PET and to study in NT1 the relationships between microglia density in the hypothalamus and in other regions of interest (ROIs) with disease duration, severity, and ORX levels. METHODS: Patients with NT1 and controls underwent a standardized clinical evaluation and [18F]DPA-714 PET imaging using a radiolabeled ligand specific to the 18 kDa translocator protein (TSPO). TSPO genotyping determined receptor affinity. Images were processed on peripheral module interface using standard uptake value (SUV) on ROIs: hypothalamus, thalamus, frontal area, cerebellum, and the whole brain. SUV ratios (SUVr) were calculated by normalizing SUV with cerebellum uptake. RESULTS: A total of 41 patients with NT1 (21 adults, 20 children, 10 with recent disease onset <1 year) and 35 controls were included, with no significant difference between groups for [18F]DPA-714 binding (SUV/SUVr) in the hypothalamus and thalamus. Unexpectedly, significantly lower SUVr in the whole brain was found in NT1 compared with controls (0.97 ± 0.06 vs 1.08 ± 0.22, p = 0.04). The same finding between NT1 and controls in the whole brain was observed in those with high or mixed TSPO affinity (p = 0.03 and p = 0.04). Similar trend was observed in the frontal area in NT1 (0.96 ± 0.09 vs 1.09 ± 0.25, p = 0.05). In NT1, no association was found between SUVr in different ROIs and age, disease duration, severity, or ORX levels. DISCUSSION: We found no evidence of in vivo increased microglia density in NT1 compared with controls, even close to disease onset, and even unexpectedly a decrease in the whole brain of these patients. These findings do not support the presence of neuroinflammation in the destruction process of ORX neurons. TRIAL REGISTRATION INFORMATION: ClinicalTrials.org NCT03754348.


Assuntos
Microglia , Narcolepsia , Orexinas , Tomografia por Emissão de Pósitrons , Humanos , Masculino , Feminino , Microglia/metabolismo , Narcolepsia/metabolismo , Narcolepsia/genética , Narcolepsia/diagnóstico por imagem , Orexinas/metabolismo , Adulto , Adulto Jovem , Tálamo/metabolismo , Tálamo/diagnóstico por imagem , Pirazóis , Hipotálamo/metabolismo , Hipotálamo/diagnóstico por imagem , Hipotálamo/patologia , Índice de Gravidade de Doença , Pessoa de Meia-Idade , Pirimidinas , Adolescente , Receptores de GABA/metabolismo , Receptores de GABA/genética
3.
Eur J Pharmacol ; 972: 176561, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580182

RESUMO

Neuronal depression in the thalamus underlies anesthetic-induced loss of consciousness, while the precise sub-thalamus nuclei and molecular targets involved remain to be elucidated. The present study investigated the role of extrasynaptic GABAA receptors in the central medial thalamic nucleus (CM) in anesthesia induced by gaboxadol (THIP) and diazepam (DZP) in rats. Local lesion of the CM led to a decrease in the duration of loss of righting reflex induced by THIP and DZP. CM microinjection of THIP but not DZP induced anesthesia. The absence of righting reflex in THIP-treated rats was consistent with the increase of low frequency oscillations in the delta band in the medial prefrontal cortex. CM microinjection of GABAA receptor antagonist SR95531 significantly attenuated the anesthesia induced by systemically-administered THIP, but not DZP. Moreover, the rats with declined expression of GABAA receptor δ-subunit in the CM were less responsive to THIP or DZP. These findings explained a novel mechanism of THIP-induced loss of consciousness and highlighted the role of CM extrasynaptic GABAA receptors in mediating anesthesia.


Assuntos
Anestesia , Isoxazóis , Receptores de GABA-A , Animais , Receptores de GABA-A/metabolismo , Masculino , Ratos , Isoxazóis/farmacologia , Diazepam/farmacologia , Ratos Sprague-Dawley , Núcleo Mediodorsal do Tálamo/efeitos dos fármacos , Núcleo Mediodorsal do Tálamo/metabolismo , Núcleo Mediodorsal do Tálamo/fisiologia , Reflexo de Endireitamento/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Tálamo/efeitos dos fármacos , Tálamo/metabolismo
4.
Schizophr Res ; 267: 451-461, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643726

RESUMO

The methylazoxymethanol acetate (MAM) rodent model is used to study aspects of schizophrenia. However, numerous studies that have employed this model have used only males, resulting in a dearth of knowledge on sex differences in brain function and behaviour. The purpose of this study was to determine whether differences exist between male and female MAM rats in neuronal oscillatory function within and between the prefrontal cortex (PFC), ventral hippocampus (vHIP) and thalamus, behaviour, and in proteins linked to schizophrenia neuropathology. We showed that female MAM animals exhibited region-specific alterations in theta power, elevated low and high gamma power in all regions, and elevated PFC-thalamus high gamma coherence. Male MAM rats had elevated beta and low gamma power in PFC, and elevated vHIP-thalamus coherence. MAM females displayed impaired reversal learning whereas MAM males showed impairments in spatial memory. Glycogen synthase kinase-3 (GSK-3) was altered in the thalamus, with female MAM rats displaying elevated GSK-3α phosphorylation. Male MAM rats showed higher expression and phosphorylation GSK-3α, and higher expression of GSK-ß. Sex-specific changes in phosphorylated Tau levels were observed in a region-specific manner. These findings demonstrate there are notable sex differences in behaviour, oscillatory network function, and GSK-3 signaling in MAM rats, thus highlighting the importance of inclusion of both sexes when using this model to study schizophrenia.


Assuntos
Modelos Animais de Doenças , Acetato de Metilazoximetanol , Esquizofrenia , Caracteres Sexuais , Animais , Acetato de Metilazoximetanol/farmacologia , Esquizofrenia/fisiopatologia , Esquizofrenia/induzido quimicamente , Esquizofrenia/metabolismo , Feminino , Masculino , Ratos , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiopatologia , Córtex Pré-Frontal/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Tálamo/efeitos dos fármacos , Tálamo/fisiopatologia , Tálamo/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas tau/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/fisiologia , Neurônios/patologia , Ratos Sprague-Dawley
5.
Exp Neurol ; 376: 114775, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604438

RESUMO

OBJECTIVE: Sleep-related hypermotor epilepsy (SHE) is a focal epilepsy syndrome characterized by seizures that predominantly occur during sleep. The pathogenesis of these seizures remains unclear. We previously detected rare variants in GABRG2, which encodes the γ2 subunit of γ-aminobutyric acid type A receptor (GABAAR), in patients with SHE and demonstrated that these variants impaired GABAAR function in vitro. However, the mechanisms by which GABRG2 variants contribute to seizure attacks during sleep remain unclear. METHODS: In this study, we designed a knock-in (KI) mouse expressing the mouse Gabrg2 T316N variant, corresponding to human GABRG2 T317N variant, using CRISPR/Cas9. Continuous video-electroencephalogram monitoring and in vivo multichannel electrophysiological recordings were performed to explore seizure susceptibility to pentylenetetrazol (PTZ), alterations in the sleep-wake cycle, spontaneous seizure patterns, and synchronized activity in the motor thalamic nuclei (MoTN) and secondary motor cortex (M2). Circadian variations in the expression of total, membrane-bound, and synaptic GABAAR subunits were also investigated. RESULTS: No obvious changes in gross morphology were detected in Gabrg2T316N/+ mice compared to their wild-type (Gabrg2+/+) littermates. Gabrg2T316N/+ mice share key phenotypes with patients, including sleep fragmentation and spontaneous seizures during sleep. Gabrg2T316N/+ mice showed increased susceptibility to PTZ-induced seizures and higher mortality after seizures. Synchronization of the local field potentials between the MoTN and M2 was abnormally enhanced in Gabrg2T316N/+ mice during light phase, when sleep dominates, accompanied by increased local activities in the MoTN and M2. Interestingly, in Gabrg2+/+ mice, GABAAR γ2 subunits showed a circadian increase on the neuronal membrane and synaptosomes in the transition from dark phase to light phase, which was absent in Gabrg2T316N/+ mice. CONCLUSION: We generated a new SHE mouse model and provided in vivo evidence that rare variants of GABRG2 contribute to seizure attacks during sleep in SHE.


Assuntos
Receptores de GABA-A , Animais , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Camundongos , Fenótipo , Sono/fisiologia , Sono/genética , Masculino , Camundongos Transgênicos , Tálamo/metabolismo , Tálamo/patologia , Camundongos Endogâmicos C57BL , Eletroencefalografia , Técnicas de Introdução de Genes , Epilepsia/genética , Epilepsia/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Feminino
6.
J Affect Disord ; 356: 470-476, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608766

RESUMO

Previous large-sample postmortem study revealed that the expression of miR-1202 in brain tissues from Brodmann area 44 (BA44) was dysregulated in patients with major depressive disorder (MDDs). However, the specific in vivo neuropathological mechanism of miR-1202 as well as its interplay with BA44 circuits in the depressed brain are still unclear. Here, we performed a case-control study with imaging-genetic approach based on resting-state functional magnetic resonance imaging (MRI) data and miR-1202 quantification from 110 medication-free MDDs and 102 healthy controls. Serum-derived circulating exosomes that readily cross the blood-brain barrier were isolated to quantify miR-1202. For validation, repeated MR scans were performed after a six-week follow-up of antidepressant treatment on a cohort of MDDs. Voxelwise factorial analysis revealed two brain areas (including the striatal-thalamic region) in which the effect of depression on the functional connectivity with BA44 was significantly dependent on the expression level of exosomal miR-1202. Moreover, longitudinal change of the BA44 connectivity with the striatal-thalamic region in MDDs after antidepressant treatment was found to be significantly related to the level of miR-1202 expression. These findings revealed that the in vivo neuropathological effect of miR-1202 dysregulation in depression is possibly exerted by mediating neural functional abnormalities in BA44-striatal-thalamic circuits.


Assuntos
Transtorno Depressivo Maior , Exossomos , Imageamento por Ressonância Magnética , MicroRNAs , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/genética , Masculino , Feminino , MicroRNAs/genética , Adulto , Exossomos/metabolismo , Exossomos/genética , Estudos de Casos e Controles , Pessoa de Meia-Idade , Antidepressivos/uso terapêutico , Antidepressivos/farmacologia , Tálamo/diagnóstico por imagem , Tálamo/metabolismo , Tálamo/fisiopatologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia
7.
Nat Commun ; 15(1): 2762, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553447

RESUMO

The significance of transient neuropeptide expression during postnatal brain development is unknown. Here, we show that galanin expression in the ventrobasal thalamus of infant mice coincides with whisker map development and modulates subcortical circuit wiring. Time-resolved neuroanatomy and single-nucleus RNA-seq identified complementary galanin (Gal) and galanin receptor 1 (Galr1) expression in the ventrobasal thalamus and the principal sensory nucleus of the trigeminal nerve (Pr5), respectively. Somatodendritic galanin release from the ventrobasal thalamus was time-locked to the first postnatal week, when Gal1R+ Pr5 afferents form glutamatergic (Slc17a6+) synapses for the topographical whisker map to emerge. RNAi-mediated silencing of galanin expression disrupted glutamatergic synaptogenesis, which manifested as impaired whisker-dependent exploratory behaviors in infant mice, with behavioral abnormalities enduring into adulthood. Pharmacological probing of receptor selectivity in vivo corroborated that target recognition and synaptogenesis in the thalamus, at least in part, are reliant on agonist-induced Gal1R activation in inbound excitatory axons. Overall, we suggest a neuropeptide-dependent developmental mechanism to contribute to the topographical specification of a fundamental sensory neurocircuit in mice.


Assuntos
Galanina , Vibrissas , Animais , Humanos , Camundongos , Axônios/metabolismo , Encéfalo/metabolismo , Galanina/metabolismo , Tálamo/metabolismo , Vibrissas/fisiologia
8.
Neurosci Bull ; 40(4): 439-450, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38015349

RESUMO

While somatosensory over-reactivity is a common feature of autism spectrum disorders such as fragile X syndrome (FXS), the thalamic mechanisms underlying this remain unclear. Here, we found that the developmental elimination of synapses formed between the principal nucleus of V (PrV) and the ventral posterior medial nucleus (VPm) of the somatosensory system was delayed in fragile X mental retardation 1 gene knockout (Fmr1 KO) mice, while the developmental strengthening of these synapses was disrupted. Immunohistochemistry showed excessive VGluT2 puncta in mutants at P12-13, but not at P7-8 or P15-16, confirming a delay in somatic pruning of PrV-VPm synapses. Impaired synaptic function was associated with a reduction in the frequency of quantal AMPA events, as well as developmental deficits in presynaptic vesicle size and density. Our results uncovered the developmental impairment of thalamic relay synapses in Fmr1 KO mice and suggest that a thalamic contribution to the somatosensory over-reactivity in FXS should be considered.


Assuntos
Transtorno do Espectro Autista , Síndrome do Cromossomo X Frágil , Camundongos , Animais , Síndrome do Cromossomo X Frágil/genética , Camundongos Knockout , Modelos Animais de Doenças , Tálamo/metabolismo , Sinapses/metabolismo , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo
9.
J Cereb Blood Flow Metab ; 44(2): 224-238, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37898107

RESUMO

Ischemic stroke causes secondary neurodegeneration in the thalamus ipsilateral to the infarction site and impedes neurological recovery. Axonal degeneration of thalamocortical fibers and autophagy overactivation are involved in thalamic neurodegeneration after ischemic stroke. However, the molecular mechanisms underlying thalamic neurodegeneration remain unclear. Sterile /Armadillo/Toll-Interleukin receptor homology domain protein (SARM1) can induce Wallerian degeneration. Herein, we aimed to investigate the role of SARM1 in thalamic neurodegeneration and autophagy activation after photothrombotic infarction. Neurological deficits measured using modified neurological severity scores and adhesive-removal test were ameliorated in Sarm1-/- mice after photothrombotic infarction. Compared with wild-type mice, Sarm1-/- mice exhibited unaltered infarct volume; however, there were markedly reduced neuronal death and gliosis in the ipsilateral thalamus. In parallel, autophagy activation was attenuated in the thalamus of Sarm1-/- mice after cerebral infarction. Thalamic Sarm1 re-expression in Sarm1-/- mice increased thalamic neurodegeneration and promoted autophagy activation. Auotophagic inhibitor 3-methyladenine partially alleviated thalamic damage induced by SARM1. Moreover, autophagic initiation through rapamycin treatment aggravated post-stroke neuronal death and gliosis in Sarm1-/- mice. Taken together, SARM1 contributes to secondary thalamic neurodegeneration after cerebral infarction, at least partly through autophagy inhibition. SARM1 deficiency is a potential therapeutic strategy for secondary thalamic neurodegeneration and functional deficits after stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Camundongos , Animais , Gliose , Infarto Cerebral/metabolismo , Acidente Vascular Cerebral/metabolismo , AVC Isquêmico/metabolismo , Tálamo/metabolismo , Axônios/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Proteínas do Domínio Armadillo/genética , Proteínas do Domínio Armadillo/metabolismo
10.
J Cereb Blood Flow Metab ; 44(4): 477-490, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37988123

RESUMO

Neuronal loss in the ipsilateral thalamus after focal cortical infarction participates in post-stroke cognitive deficits, and enhanced angiogenesis in the thalamus is expected to reduce neuronal damage. We hypothesize that novel translocator protein (TSPO) ligand, 2-Cl-MGV-1, can promote angiogenesis, attenuate neuronal loss in the thalamus, and ameliorate post-stroke cognitive deficits. Cortical infarction was induced by distal middle cerebral artery occlusion (dMCAO) in stroke-prone renovascular hypertensive rats. 2-Cl-MGV-1 or dimethyl sulfoxide was administered 24 h after dMCAO and then for 6 or 13 days. Spatial learning and memory were assessed using the Morris water maze. Neuronal loss, TSPO expression, angiogenesis, and intrinsic pathway were determined by immunofluorescence and immunoblotting 7 and 14 days after dMCAO. Cortical infarction caused post-stroke cognitive deficits and secondary neuronal loss with gliosis in the ipsilateral thalamus within 14 days of dMCAO. Increased angiogenesis and elevated expression of vascular TSPO were detected in the ipsilateral thalamus, and treatment with 2-Cl-MGV-1 enhanced angiogenesis by stimulating the PI3K-AKT-mTOR pathway. The effects of 2-Cl-MGV-1 on angiogenesis coincided with reduced neuronal loss in the thalamus and contributed to improvements in post-stroke cognitive deficits. Our findings suggest that 2-Cl-MGV-1 stimulates angiogenesis, ameliorates neuronal loss in the thalamus, and improves post-stroke cognitive deficits.


Assuntos
Angiogênese , Carbamatos , Quinazolinas , Acidente Vascular Cerebral , Ratos , Animais , Ratos Sprague-Dawley , Ligantes , Fosfatidilinositol 3-Quinases/metabolismo , Infarto da Artéria Cerebral Média/complicações , Acidente Vascular Cerebral/metabolismo , Tálamo/metabolismo , Cognição
11.
Neurosci Lett ; 820: 137595, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38096972

RESUMO

The current study was designed to examine the role of glutamate NMDA receptors of the mediodorsal thalamus (MD) in scopolamine-induced memory impairment. Adult male rats were bilaterally cannulated into the MD. According to the results, intraperitoneal (i.p.) administration of scopolamine (1.5 mg/kg) immediately after the training phase (post-training) impaired memory consolidation. Bilateral microinjection of the glutamate NMDA receptors agonist, N-Methyl-D-aspartic acid (NMDA; 0.05 µg/rat), into the MD significantly improved scopolamine-induced memory consolidation impairment. Co-administration of D-AP5, a glutamate NMDA receptor antagonist (0.001-0.005 µg/rat, intra-MD) potentiated the response of an ineffective dose of scopolamine (0.5 mg/kg, i.p.) to impair memory consolidation, mimicking the response of a higher dose of scopolamine. Noteworthy, post-training intra-MD microinjections of the same doses of NMDA or D-AP5 alone had no effect on memory consolidation. Moreover, the blockade of the glutamate NMDA receptors by 0.003 ng/rat of D-AP5 prevented the improving effect of NMDA on scopolamine-induced amnesia. Thus, it can be concluded that the MD glutamatergic system may be involved in scopolamine-induced memory impairment via the NMDA receptor signaling pathway.


Assuntos
N-Metilaspartato , Escopolamina , Ratos , Masculino , Animais , Escopolamina/farmacologia , N-Metilaspartato/farmacologia , Receptores de N-Metil-D-Aspartato/metabolismo , Ácido Glutâmico/metabolismo , Ratos Wistar , Amnésia/induzido quimicamente , Transtornos da Memória/induzido quimicamente , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Tálamo/metabolismo , Aprendizagem da Esquiva
12.
Cytokine ; 174: 156468, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38101167

RESUMO

It has been shown that AMP-activated protein kinase (AMPK) is involved in the nociceptive processing. This observation has prompted us to investigate the effects of the AMPK activator metformin on the paclitaxel-induced mechanical allodynia, a well-established model of neuropathic pain. Mechanical allodynia was induced by four intraperitoneal (i.p) injections of paclitaxel (2 mg/kg.day) in mice. Metformin was administered per os (p.o.). Naltrexoneandglibenclamide were used to investigate mechanisms mediating metformin activity. Concentrations of cytokines in the dorsal root ganglia (DRG) and thalamus were determined. After a single p.o. administration, the two highest doses of metformin (500 and 1000 mg/kg) attenuated the mechanical allodynia. This response was attenuated by all doses of metformin (250, 500 and 1000 mg/kg) when two administrations, 2 h apart, were carried out. Naltrexone (5 and 10 mg/kg, i.p.), but not glibenclamide (20 and 40 mg/kg, p.o.), attenuated metformin activity. Concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß and CXCL-1 in the DRG were increased after administration of paclitaxel. Metformin (1000 mg/kg) reduced concentrations of TNF-α, IL-1ß and CXCL-1 in the DRG. Concentration of IL-6, but not TNF-α, in the thalamus was increased after administration of paclitaxel. Metformin (1000 mg/kg) reduced concentration of IL-6 in the thalamus. In summary, metformin exhibits activity in the model of neuropathic pain induced by paclitaxel. This activity may be mediated by activation of opioidergic pathways and reduced production of TNF-α, IL-1ß and CXCL-1 in the DRG and IL-6 in the thalamus.


Assuntos
Metformina , Neuralgia , Camundongos , Animais , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Paclitaxel/efeitos adversos , Fator de Necrose Tumoral alfa/metabolismo , Metformina/farmacologia , Gânglios Espinais/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Interleucina-6/metabolismo , Citocinas/metabolismo , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Tálamo/metabolismo
13.
Nat Commun ; 14(1): 8481, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123574

RESUMO

The risk of developing drug addiction is strongly influenced by the epigenetic landscape and chromatin remodeling. While histone modifications such as methylation and acetylation have been studied in the ventral tegmental area and nucleus accumbens (NAc), the role of H2A monoubiquitination remains unknown. Our investigations, initially focused on the scaffold protein melanoma-associated antigen D1 (Maged1), reveal that H2A monoubiquitination in the paraventricular thalamus (PVT) significantly contributes to cocaine-adaptive behaviors and transcriptional repression induced by cocaine. Chronic cocaine use increases H2A monoubiquitination, regulated by Maged1 and its partner USP7. Accordingly, Maged1 specific inactivation in thalamic Vglut2 neurons, or USP7 inhibition, blocks cocaine-evoked H2A monoubiquitination and cocaine locomotor sensitization. Additionally, genetic variations in MAGED1 and USP7 are linked to altered susceptibility to cocaine addiction and cocaine-associated symptoms in humans. These findings unveil an epigenetic modification in a non-canonical reward pathway of the brain and a potent marker of epigenetic risk factors for drug addiction in humans.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Transtornos Relacionados ao Uso de Substâncias , Humanos , Peptidase 7 Específica de Ubiquitina/metabolismo , Cocaína/farmacologia , Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/genética , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Transtornos Relacionados ao Uso de Substâncias/genética , Epigênese Genética , Núcleo Accumbens/metabolismo , Tálamo/metabolismo
14.
Psychiatry Res Neuroimaging ; 335: 111719, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37806261

RESUMO

Parkinson's disease (PD), multisystem atrophy (MSA), and progressive supranuclear palsy (PSP) present similarly with bradykinesia, tremor, rigidity, and cognitive impairments. Neuroimaging studies have found differential changes in the nigrostriatal pathway in these disorders, however whether the volume and shape of specific regions within this pathway can distinguish between atypical Parkinsonian disorders remains to be determined. This paper investigates striatal and thalamic volume and morphology as distinguishing biomarkers, and their relationship to neuropsychiatric symptoms. Automatic segmentation to calculate volume and shape analysis of the caudate nucleus, putamen, and thalamus were performed in 18 PD patients, 12 MSA, 15 PSP, and 20 healthy controls, then correlated with clinical measures. PSP bilateral thalami and right putamen were significantly smaller than controls, but not MSA or PD. The left caudate and putamen significantly correlated with the Neuropsychiatric Inventory total score. Bilateral thalamus, caudate, and left putamen had significantly different morphology between groups, driven by differences between PSP and healthy controls. This study demonstrated that PSP patient striatal and thalamic volume and shape are significantly different when compared with controls. Parkinsonian disorders could not be differentiated on volumetry or morphology, however there are trends for volumetric and morphological changes associated with PD, MSA, and PSP.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Transtornos Parkinsonianos , Paralisia Supranuclear Progressiva , Humanos , Doença de Parkinson/diagnóstico por imagem , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Transtornos Parkinsonianos/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/metabolismo
15.
Int J Mol Sci ; 24(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37834446

RESUMO

The thalamus plays a crucial role in ensuring the faithful transfer of sensory information, except olfactory signals, to corresponding cortical areas. However, thalamic function is not simply restricted to relaying information to and from the cerebral cortex. The ability to modulate the flow of sensory information is supported by a second abundant neuronal type in the prethalamus, the inhibitory gamma-aminobutyric acid (GABAergic) neurons, which project inhibitory GABAergic axons to dorsal thalamic glutamatergic neurons. Interestingly, during the trajectory of pioneer prethalamic axons, morphogen fibroblast growth factor (FGF)-3 is expressed in the ventral chick hypothalamus. Using in vitro analyses in chick explants, we identify a chemorepellent effect of FGF3 on nearby prethalamic GABAergic axons. Furthermore, inhibition of FGF3 guidance functions indicates that FGF3 signaling is necessary to navigate prethalamic axons correctly. Gene expression analyses and loss of function studies demonstrate that FGF3 mediates prethalamic axonal guidance through the downstream pathway of the FGF receptor (FGFR)-1. Together, these results suggest that FGF3 expressed in the hypothalamus functions as a chemorepellent molecule to direct the pathway selection of neighboring GABAergic axons.


Assuntos
Axônios , Tálamo , Axônios/metabolismo , Tálamo/metabolismo , Córtex Cerebral , Neurônios , Hipotálamo
16.
Mol Brain ; 16(1): 74, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37904209

RESUMO

Necroptosis is known to play an important role in the pathophysiology of cerebral ischemia; however, its role in the occurrence of secondary thalamic injury after focal cerebral infarction and the mechanism about how mixed lineage kinase domain-like (MLKL) executes necroptosis in this pathophysiology are still unclear. In this study, Sprague-Dawley rats were subjected to distal branch of middle cerebral artery occlusion (dMCAO). The expression of MLKL, connexin 43 (Cx43) and Von Hippel-Lindau (VHL) in vitro and in vivo were assessed by Western blot. Bioinformatic methods were used to predict the potential binding sites where MLKL interacted with Cx43, and the ubiquitination degradation of Cx43 regulated by VHL. The interactions among MLKL, Cx43, VHL, and Ubiquitin were assessed by immunoprecipitation. Dye uptake assay were used to examine the Cx43 hemichannels. Intracellular Ca2+ concentration was measured using Fluo-4 AM. Overexpression and site-directed mutagenesis studies were used to study the mechanisms by which MLKL regulates Cx43 ubiquitinational degradation to mediate neuronal necroptosis. We found that MLKL and Cx43 were upregulated in the ventral posterolateral nucleus (VPN) of the ipsilateral thalamus after dMCAO. In the in vitro experiments MLKL and Cx43 were upregulated after TSZ-mediated necroptosis in SH-SY5Y cells. The interaction between MLKL and Cx43 inhibited the K48-linked ubiquitination of Cx43 in necroptotic SH-SY5Y cells. VHL is an E3 ubiquitin ligase for Cx43, and MLKL competes with VHL for binding to Cx43. Interaction of MLKL Ser454 with Cx43 can trigger the opening of Cx43 hemichannels, causing increased intracellular Ca2+, and cell necroptosis. This innovative study at animal models, cellular, and molecular levels is anticipated to clarify the roles of MLKL and Cx43 in thalamic damage after focal cortical infarction. Our findings may help identify novel targets for neurological recovery after cortical infarction.


Assuntos
Conexina 43 , Neuroblastoma , Animais , Humanos , Ratos , Infarto Cerebral , Necroptose , Neuroblastoma/metabolismo , Proteínas Quinases/metabolismo , Ratos Sprague-Dawley , Tálamo/metabolismo
17.
Stem Cells Transl Med ; 12(8): 553-568, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37399126

RESUMO

Human embryonic stem cells-derived neural progenitor cells (hESCs-NPCs) transplantation holds great potential to treat stroke. We previously reported that delayed secondary degeneration occurs in the ventroposterior nucleus (VPN) of ipsilateral thalamus after distal branch of middle cerebral artery occlusion (dMCAO) in adult male Sprague-Dawley (SD) rats. In this study, we investigate whether hESCs-NPCs would benefit the neural recovery of the secondary damage in the VPN after focal cerebral infarction. Permanent dMCAO was performed with electrocoagulation. Rats were randomized into Sham, dMCAO groups with or without hESCs-NPCs treatment. HESCs-NPCs were engrafted into the peri-infarct regions of rats at 48 h after dMCAO. The transplanted hESCs-NPCs survive and partially differentiate into mature neurons after dMCAO. Notably, hESCs-NPCs transplantation attenuated secondary damage of ipsilateral VPN and improved neurological functions of rats after dMCAO. Moreover, hESCs-NPCs transplantation significantly enhanced the expression of BDNF and TrkB and their interaction in ipsilateral VPN after dMCAO, which was reversed by the knockdown of TrkB. Transplantated hESCs-NPCs reconstituted thalamocortical connection and promoted the formation of synapses in ipsilateral VPN post-dMCAO. These results suggest that hESCs-NPCs transplantation attenuates secondary damage of ipsilateral thalamus after cortical infarction, possibly through activating BDNF/TrkB pathway, enhancing thalamocortical projection, and promoting synaptic formation. It provides a promising therapeutic strategy for secondary degeneration in the ipsilateral thalamus post-dMCAO.


Assuntos
Células-Tronco Embrionárias , Infarto da Artéria Cerebral Média , Células-Tronco Neurais , Humanos , Células-Tronco Embrionárias/transplante , Animais , Ratos , Ratos Sprague-Dawley , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/terapia , Células-Tronco Neurais/transplante , Diferenciação Celular , Movimento Celular , Transdução de Sinais , Neuroproteção , Tálamo/metabolismo
18.
J Neuroimmunol ; 382: 578150, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37467699

RESUMO

Epidemiological studies showed that Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA) frequently co-occur; however, the precise mechanism is not well understood. A unique animal model (Tg-SwDI mice) was developed to investigate the early-onset and robust accumulation of both parenchymal and vascular Aß in the brain. Tg-SwDI mice have been extensively used to study the mechanisms of cerebrovascular dysfunction, neuroinflammation, neurodegeneration, and cognitive decline observed in AD/CAA patients and to design biomarkers and therapeutic strategies. In the present study, we documented interesting new features in the thalamus of Tg-SwDI mice: 1) a sharp increase in the expression of ionized calcium-binding adapter molecule 1 (Iba-1) in microglia in 6-month-old animals; 2) microglia clustering at six months that disappeared in old animals; 3) N-truncated/modified AßN3(pE) peptide in 9-month-old female and 12-month-old male mice; 4) an age-dependent increase in translocator protein (TSPO) expression. These findings reinforce the versatility of this model for studying multiple pathological issues involved in AD and CAA.


Assuntos
Doença de Alzheimer , Angiopatia Amiloide Cerebral , Animais , Feminino , Masculino , Camundongos , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides , Encéfalo/metabolismo , Angiopatia Amiloide Cerebral/complicações , Angiopatia Amiloide Cerebral/genética , Angiopatia Amiloide Cerebral/metabolismo , Modelos Animais de Doenças , Camundongos Transgênicos , Microglia/metabolismo , Ácido Pirrolidonocarboxílico/metabolismo , Ácido Pirrolidonocarboxílico/uso terapêutico , Tálamo/metabolismo
19.
Neuropsychopharmacology ; 48(13): 1931-1940, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37474763

RESUMO

It is well-established that stress and negative affect trigger eating disorder symptoms and that the brains of men and women respond to stress in different ways. Indeed, women suffer disproportionately from emotional or stress-related eating, as well as associated eating disorders such as binge eating disorder. Nevertheless, our understanding of the precise neural circuits driving this maladaptive eating behavior, particularly in women, remains limited. We recently established a clinically relevant model of 'emotional' stress-induced binge eating whereby only female mice display binge eating in response to an acute "emotional" stressor. Here, we combined neuroanatomic, transgenic, immunohistochemical and pathway-specific chemogenetic approaches to investigate whole brain functional architecture associated with stress-induced binge eating in females, focusing on the role of Vglut2 projections from the paraventricular thalamus (PVTVglut2+) to the medial insular cortex in this behavior. Whole brain activation mapping and hierarchical clustering of Euclidean distances revealed distinct patterns of coactivation unique to stress-induced binge eating. At a pathway-specific level, PVTVglut2+ cells projecting to the medial insular cortex were specifically activated in response to stress-induced binge eating. Subsequent chemogenetic inhibition of this pathway suppressed stress-induced binge eating. We have identified a distinct PVTVglut2+ to insular cortex projection as a key driver of "emotional" stress-induced binge eating in female mice, highlighting a novel circuit underpinning this sex-specific behavior.


Assuntos
Transtorno da Compulsão Alimentar , Bulimia , Humanos , Masculino , Feminino , Camundongos , Animais , Córtex Insular , Bulimia/metabolismo , Encéfalo/metabolismo , Tálamo/metabolismo
20.
Int J Mol Sci ; 24(11)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37298594

RESUMO

Monocarboxylate transporter 8 (MCT8) and organic anion-transporting polypeptide 1C1 (OATP1C1) are thyroid hormone (TH) transmembrane transporters relevant for the availability of TH in neural cells, crucial for their proper development and function. Mutations in MCT8 or OATP1C1 result in severe disorders with dramatic movement disability related to alterations in basal ganglia motor circuits. Mapping the expression of MCT8/OATP1C1 in those circuits is necessary to explain their involvement in motor control. We studied the distribution of both transporters in the neuronal subpopulations that configure the direct and indirect basal ganglia motor circuits using immunohistochemistry and double/multiple labeling immunofluorescence for TH transporters and neuronal biomarkers. We found their expression in the medium-sized spiny neurons of the striatum (the receptor neurons of the corticostriatal pathway) and in various types of its local microcircuitry interneurons, including the cholinergic. We also demonstrate the presence of both transporters in projection neurons of intrinsic and output nuclei of the basal ganglia, motor thalamus and nucleus basalis of Meynert, suggesting an important role of MCT8/OATP1C1 for modulating the motor system. Our findings suggest that a lack of function of these transporters in the basal ganglia circuits would significantly impact motor system modulation, leading to clinically severe movement impairment.


Assuntos
Gânglios da Base , Transportadores de Ânions Orgânicos , Simportadores , Adulto , Humanos , Gânglios da Base/metabolismo , Encéfalo/metabolismo , Interneurônios/metabolismo , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neurônios/metabolismo , Transportadores de Ânions Orgânicos/metabolismo , Simportadores/genética , Simportadores/metabolismo , Tálamo/metabolismo , Hormônios Tireóideos/metabolismo
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