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1.
Mol Neurobiol ; 60(10): 5755-5769, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37341859

RESUMO

The purpose of this study was to identify and validate new putative lead drug targets in drug-resistant mesial temporal lobe epilepsy (mTLE) starting from differentially expressed genes (DEGs) previously identified in mTLE in humans by transcriptome analysis. We identified consensus DEGs among two independent mTLE transcriptome datasets and assigned them status as "lead target" if they (1) were involved in neuronal excitability, (2) were new in mTLE, and (3) were druggable. For this, we created a consensus DEG network in STRING and annotated it with information from the DISEASES database and the Target Central Resource Database (TCRD). Next, we attempted to validate lead targets using qPCR, immunohistochemistry, and Western blot on hippocampal and temporal lobe neocortical tissue from mTLE patients and non-epilepsy controls, respectively. Here we created a robust, unbiased list of 113 consensus DEGs starting from two lists of 3040 and 5523 mTLE significant DEGs, respectively, and identified five lead targets. Next, we showed that CACNB3, a voltage-gated Ca2+ channel subunit, was significantly regulated in mTLE at both mRNA and protein level. Considering the key role of Ca2+ currents in regulating neuronal excitability, this suggested a role for CACNB3 in seizure generation. This is the first time changes in CACNB3 expression have been associated with drug-resistant epilepsy in humans, and since efficient therapeutic strategies for the treatment of drug-resistant mTLE are lacking, our finding might represent a step toward designing such new treatment strategies.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Humanos , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/complicações , Lobo Temporal/metabolismo , Convulsões/metabolismo , Hipocampo/metabolismo , Epilepsia Resistente a Medicamentos/genética , Epilepsia Resistente a Medicamentos/metabolismo
2.
Gene Ther ; 30(7-8): 649-658, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029201

RESUMO

Gene therapy with AAV vectors carrying genes for neuropeptide Y and its receptor Y2 has been shown to inhibit seizures in multiple animal models of epilepsy. It is however unknown how the AAV serotype or the sequence order of these two transgenes in the expression cassette affects the actual parenchymal gene expression levels and the seizure-suppressant efficacy. To address these questions, we compared three viral vector serotypes (AAV1, AAV2 and AAV8) and two transgene sequence orders (NPY-IRES-Y2 and Y2-IRES-NPY) in a rat model of acutely induced seizures. Wistar male rats were injected bilaterally with viral vectors and 3 weeks later acute seizures were induced by a subcutaneous injection of kainate. The latency until 1st motor seizure, time spent in motor seizure and latency to status epilepticus were measured to evaluate the seizure-suppressing efficacy of these vectors compared to an empty cassette control vector. Based on the results, the effect of the AAV1-NPY-IRES-Y2 vector was further investigated by in vitro electrophysiology, and its ability to achieve transgene overexpression in resected human hippocampal tissue was evaluated. The AAV1-NPY-IRES-Y2 proved to be better to any other serotype or gene sequence considering both transgene expression and ability to suppress induced seizures in rats. The vector also demonstrated transgene-induced decrease of glutamate release from excitatory neuron terminals and significantly increased both NPY and Y2 expression in resected human hippocampal tissue from patients with drug-resistant temporal lobe epilepsy. These results validate the feasibility of NPY/Y2 receptor gene therapy as a therapeutic opportunity in focal epilepsies.


Assuntos
Epilepsia , Convulsões , Ratos , Masculino , Humanos , Animais , Sorogrupo , Ratos Wistar , Convulsões/genética , Convulsões/terapia , Epilepsia/terapia , Neuropeptídeo Y/genética , Neuropeptídeo Y/metabolismo , Terapia Genética/métodos , Hipocampo/metabolismo
3.
Int J Mol Sci ; 23(21)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36361981

RESUMO

Glial cell line-derived neurotrophic factor (GDNF) has been shown to counteract seizures when overexpressed or delivered into the brain in various animal models of epileptogenesis or chronic epilepsy. The mechanisms underlying this effect have not been investigated. We here demonstrate for the first time that GDNF enhances GABAergic inhibitory drive onto mouse pyramidal neurons by modulating postsynaptic GABAA receptors, particularly in perisomatic inhibitory synapses, by GFRα1 mediated activation of the Ret receptor pathway. Other GDNF receptors, such as NCAM or Syndecan3, are not contributing to this effect. We observed similar alterations by GDNF in human hippocampal slices resected from epilepsy patients. These data indicate that GDNF may exert its seizure-suppressant action by enhancing GABAergic inhibitory transmission in the hippocampal network, thus counteracting the increased excitability of the epileptic brain. This new knowledge can contribute to the development of novel, more precise treatment strategies based on a GDNF gene therapy approach.


Assuntos
Fator Neurotrófico Derivado de Linhagem de Célula Glial , Hipocampo , Proteínas Proto-Oncogênicas c-ret , Células Piramidais , Animais , Humanos , Camundongos , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Sinapses/metabolismo , Células Piramidais/metabolismo
4.
Acta Neuropathol Commun ; 10(1): 113, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35974377

RESUMO

Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease characterized by the accumulation of aggregated amyloid beta (Aß) and hyperphosphorylated tau along with a slow decline in cognitive functions. Unlike advanced AD, the initial steps of AD pathophysiology have been poorly investigated, partially due to limited availability of animal models focused on the early, plaque-free stages of the disease. The aim of this study was to evaluate the early behavioral, anatomical and molecular alterations in wild-type rats following intracerebroventricular injections of human Aß oligomers (AßOs). Bioactive human AD and nondemented control brain tissue extracts were characterized using ELISA and proteomics approaches. Following a bilateral infusion, rats underwent behavioral testing, including the elevated plus maze, social recognition test, Morris water maze and Y-maze within 6 weeks postinjection. An analysis of brain structure was performed with manganese-enhanced MRI. Collected brain tissues were analyzed using stereology, immunohistochemistry, ELISA and qPCR. No sensorimotor deficits affecting motor performance on different maze tasks were observed, nor was spatial memory disturbed in AD rats. In contrast, a significant impairment of social memory became evident at 21 days postinjection. This deficit was associated with a significantly decreased volume of the lateral entorhinal cortex and a tendency toward a decrease in the total brain volume. Significant increase of cleaved caspase-3-positive cells, microglial activation and proinflammatory responses accompanied by altered expression of synaptic markers were observed in the hippocampus of AD rats with immunohistochemical and qPCR approaches at 6 weeks postinjection. Our data suggest that the social memory impairment observed in AßO-injected rats might be determined by neuroinflammatory responses and synaptopathy. An infusion of native oligomeric Aß in the rat brain represents a feasible tool to model early plaque-free events associated with AD.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Hipocampo/metabolismo , Humanos , Aprendizagem em Labirinto/fisiologia , Doenças Neurodegenerativas/metabolismo , Placa Amiloide/metabolismo , Ratos
5.
J Neurosci Res ; 100(10): 1921-1932, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35822521

RESUMO

Neuroglobin (Ngb) is found in the neurones of several different brain areas and is known to bind oxygen and other gaseous molecules and reactive oxygen species (ROS) in vitro, but it does not seem to act as a respiratory molecule for neurones. Using male and female Ngb-knockout (KO) mice, we addressed the role of Ngb in neuronal brain activity using behavioral tests but found no differences in general behaviors, memory processes, and anxiety-/depression-like behaviors. Oxidative stress and ROS play key roles in epileptogenesis, and oxidative injury produced by an excessive production of free radicals is involved in the initiation and progression of epilepsy. The ROS binding properties led us to hypothesize that lack of Ngb could affect central coping with excitatory stimuli. We consequently explored whether exposure to the excitatory molecule kainate (KA) would increase severity of seizures in mice lacking Ngb. We found that the duration and severity of seizures were increased, while the latency time to develop seizures was shortened in Ngb-KO compared to wildtype adult female mice. Consistently, c-fos expression after KA was significantly increased in Ngb-KO mice in the amygdala and piriform cortex, regions rich in Ngb and known to be centrally involved in seizure generation. Moreover, the measured c-fos expression levels were correlated with seizure susceptibility. With these new findings combined with previous studies we propose that Ngb could constitute an intrinsic defense mechanism against neuronal hyperexcitability and oxidative stress by buffering of ROS in amygdala and other Ngb-containing brain regions.


Assuntos
Neuroglobina , Convulsões , Animais , Feminino , Masculino , Camundongos , Neuroglobina/deficiência , Neuroglobina/genética , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
6.
Biomedicines ; 9(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34944691

RESUMO

Progressive degeneration of dopaminergic neurons, immune activation, and α-synuclein pathology characterize Parkinson's disease (PD). We previously reported that unilateral intranigral injection of recombinant adeno-associated viral (rAAV) vectors encoding wild-type human α-synuclein produced a rat model of early PD with dopamine terminal dysfunction. Here we tested the hypothesis that decreases in dopamine result in increased postsynaptic dopamine D2/D3 receptor expression, neuroinflammation, and reduced synaptic vesicle glycoprotein 2A (SV2A) density. Rats were injected with rAAV encoding α-synuclein or green fluorescent protein and subjected to non-pharmacological motor tests, before euthanization at 12 weeks post-injection. We performed: (1) in situ hybridization of nigral tyrosine hydroxylase mRNA, (2) HPLC of striatal dopamine content, and (3) autoradiography with [3H]raclopride, [3H]DTBZ, [3H]GBR12935, [3H]PK11195, and [3H]UCB-J to measure binding at D2/3 receptors, vesicular monoamine transporter 2, dopamine transporters, mitochondrial translocator protein, and SV2A, respectively. rAAV-α-synuclein induced motor asymmetry and reduced tyrosine hydroxylase mRNA and dopamine content in ipsilateral brain regions. This was paralleled by elevated ipsilateral postsynaptic dopamine D2/3 receptor expression and immune activation, with no changes to synaptic SV2A density. In conclusion, α-synuclein overexpression results in dopaminergic degeneration that induced compensatory increases in D2/3 binding and immune activation, recapitulating many of the pathological characteristics of PD.

8.
J Biol Chem ; 297(6): 101361, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34756883

RESUMO

The dopamine (DA) transporter (DAT) is part of a presynaptic multiprotein network involving interactions with scaffold proteins via its C-terminal PDZ domain-binding sequence. Using a mouse model expressing DAT with mutated PDZ-binding sequence (DAT-AAA), we previously demonstrated the importance of this binding sequence for striatal expression of DAT. Here, we show by application of direct stochastic reconstruction microscopy not only that the striatal level of transporter is reduced in DAT-AAA mice but also that the nanoscale distribution of this transporter is altered with a higher propensity of DAT-AAA to localize to irregular nanodomains in dopaminergic terminals. In parallel, we observe mesostriatal DA adaptations and changes in DA-related behaviors distinct from those seen in other genetic DAT mouse models. DA levels in the striatum are reduced to ∼45% of that of WT, accompanied by elevated DA turnover. Nonetheless, fast-scan cyclic voltammetry recordings on striatal slices reveal a larger amplitude and prolonged clearance rate of evoked DA release in DAT-AAA mice compared with WT mice. Autoradiography and radioligand binding show reduced DA D2 receptor levels, whereas immunohistochemistry and autoradiography show unchanged DA D1 receptor levels. In behavioral experiments, we observe enhanced self-administration of liquid food under both a fixed ratio of one and progressive ratio schedule of reinforcement but a reduction compared with WT when using cocaine as reinforcer. In summary, our data demonstrate how disruption of PDZ domain interactions causes changes in DAT expression and its nanoscopic distribution that in turn alter DA clearance dynamics and related behaviors.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Dopamina/metabolismo , Homeostase , Motivação , Domínios PDZ , Recompensa , Animais , Sítios de Ligação , Cocaína/administração & dosagem , Condicionamento Operante , Masculino , Camundongos , Ligação Proteica , Autoadministração
9.
Front Mol Neurosci ; 14: 695937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34690692

RESUMO

In recent years, gene therapy has been raising hopes toward viable treatment strategies for rare genetic diseases for which there has been almost exclusively supportive treatment. We here review this progress at the pre-clinical and clinical trial levels as well as market approvals within diseases that specifically affect the brain and spinal cord, including degenerative, developmental, lysosomal storage, and metabolic disorders. The field reached an unprecedented milestone when Zolgensma® (onasemnogene abeparvovec) was approved by the FDA and EMA for in vivo adeno-associated virus-mediated gene replacement therapy for spinal muscular atrophy. Shortly after EMA approved Libmeldy®, an ex vivo gene therapy with lentivirus vector-transduced autologous CD34-positive stem cells, for treatment of metachromatic leukodystrophy. These successes could be the first of many more new gene therapies in development that mostly target loss-of-function mutation diseases with gene replacement (e.g., Batten disease, mucopolysaccharidoses, gangliosidoses) or, less frequently, gain-of-toxic-function mutation diseases by gene therapeutic silencing of pathologic genes (e.g., amyotrophic lateral sclerosis, Huntington's disease). In addition, the use of genome editing as a gene therapy is being explored for some diseases, but this has so far only reached clinical testing in the treatment of mucopolysaccharidoses. Based on the large number of planned, ongoing, and completed clinical trials for rare genetic central nervous system diseases, it can be expected that several novel gene therapies will be approved and become available within the near future. Essential for this to happen is the in depth characterization of short- and long-term effects, safety aspects, and pharmacodynamics of the applied gene therapy platforms.

10.
Mol Metab ; 47: 101174, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33549847

RESUMO

OBJECTIVE: The goal of this study was to investigate the importance of central hormone-sensitive lipase (HSL) expression in the regulation of food intake and body weight in mice to clarify whether intracellular lipolysis in the mammalian hypothalamus plays a role in regulating appetite. METHODS: Using pharmacological and genetic approaches, we investigated the role of HSL in the rodent brain in the regulation of feeding and energy homeostasis under basal conditions during acute stress and high-fat diet feeding. RESULTS: We found that HSL, a key enzyme in the catabolism of cellular lipid stores, is expressed in the appetite-regulating centers in the hypothalamus and is activated by acute stress through a mechanism similar to that observed in adipose tissue and skeletal muscle. Inhibition of HSL in rodent models by a synthetic ligand, global knockout, or brain-specific deletion of HSL prevents a decrease in food intake normally seen in response to acute stress and is associated with the increased expression of orexigenic peptides neuropeptide Y (NPY) and agouti-related peptide (AgRP). Increased food intake can be reversed by adeno-associated virus-mediated reintroduction of HSL in neurons of the mediobasal hypothalamus. Importantly, metabolic stress induced by a high-fat diet also enhances the hyperphagic phenotype of HSL-deficient mice. Specific deletion of HSL in the ventromedial hypothalamic nucleus (VMH) or AgRP neurons reveals that HSL in the VMH plays a role in both acute stress-induced food intake and high-fat diet-induced obesity. CONCLUSIONS: Our results indicate that HSL activity in the mediobasal hypothalamus is involved in the acute reduction in food intake during the acute stress response and sensing of a high-fat diet.


Assuntos
Apetite/fisiologia , Homeostase , Hipotálamo/metabolismo , Esterol Esterase/metabolismo , Proteína Relacionada com Agouti/metabolismo , Animais , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos , Metabolismo Energético , Feminino , Hiperfagia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Obesidade/metabolismo , Fatores de Processamento de RNA , Esterol Esterase/genética , Estresse Fisiológico/genética , Transcriptoma
11.
Comput Methods Programs Biomed ; 198: 105788, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33130492

RESUMO

BACKGROUND AND OBJECTIVE: Optical coherence tomography (OCT) is a useful technique to monitor retinal layer state both in humans and animal models. Automated OCT analysis in rats is of great relevance to study possible toxic effect of drugs and other treatments before human trials. In this paper, two different approaches to detect the most significant retinal layers in a rat OCT image are presented. METHODS: One approach is based on a combination of local horizontal intensity profiles along with a new proposed variant of watershed transformation and the other is built upon an encoder-decoder convolutional network architecture. RESULTS: After a wide validation, an averaged absolute distance error of 3.77 ± 2.59 and 1.90 ± 0.91 µm is achieved by both approaches, respectively, on a batch of the rat OCT database. After a second test of the deep-learning-based method using an unseen batch of the database, an averaged absolute distance error of 2.67 ± 1.25 µm is obtained. The rat OCT database used in this paper is made publicly available to facilitate further comparisons. CONCLUSIONS: Based on the obtained results, it was demonstrated the competitiveness of the first approach since outperforms the commercial Insight image segmentation software (Phoenix Research Labs) as well as its utility to generate labelled images for validation purposes speeding significantly up the ground truth generation process. Regarding the second approach, the deep-learning-based method improves the results achieved by the more conventional method and also by other state-of-the-art techniques. In addition, it was verified that the results of the proposed network can be generalized to new rat OCT images.


Assuntos
Roedores , Tomografia de Coerência Óptica , Animais , Redes Neurais de Computação , Ratos , Retina/diagnóstico por imagem , Software
12.
Front Mol Neurosci ; 13: 232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343295

RESUMO

Gene therapy to treat pharmacoresistant temporal lobe epilepsy in humans is now being developed using an AAV vector (CG01) that encodes the combination of neuropeptide Y and its antiepileptic receptor Y2. With this in mind, the present study aimed to provide important preclinical data on the effects of CG01 on the duration of transgene expression, cellular tropism, and potential side effects on body weight and cognitive function. The CG01 vector was administered unilaterally into the dorsal and ventral hippocampus of adult male rats and expression of both transgenes was found to remain elevated without a sign of decline at 6 months post-injection. CG01 appeared to mediate expression selectively in hippocampal neurons, without expression in astrocytes or oligodendrocytes. No effects were seen on body weight as well as on short- or long-term memory as revealed by testing in the Y-maze or Morris water maze tests. Thus these data show that unilateral CG01 vector treatment as future gene therapy in pharmacoresistant temporal lobe epilepsy patients should result in stable and long-term expression predominantly in neurons and be well tolerated without side effects on body weight and cognitive function.

13.
ACS Chem Neurosci ; 11(9): 1270-1282, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32283014

RESUMO

Vascular endothelial growth factor B (VEGFB) is a pleiotropic trophic factor, which in contrast to the closely related VEGFA is known to have a limited effect on angiogenesis. VEGFB improves survival in various tissues including the nervous system, where the effect was observed mainly for peripheral neurons. The neurotrophic effect of VEGFB on central nervous system neurons has been less investigated. Here we demonstrated that VEGFB promotes neurite outgrowth from primary cerebellar granule, hippocampal, and retinal neurons in vitro. VEGFB protected hippocampal and retinal neurons from both oxidative stress and glutamate-induced neuronal death. The VEGF receptor 1 (VEGFR1) is required for VEGFB-induced neurotrophic and neuroprotective effects. Using a structure-based approach, we designed short peptides, termed Vefin1-7, mimicking the binding interface of VEGFB to VEGFR1. Vefins were analyzed for their secondary structure and binding to VEGF receptors and compared with previously described peptides derived from VEGFA, another ligand of VEGFR1. We show that Vefins have neurotrophic and neuroprotective effects on primary hippocampal, cerebellar granule, and retinal neurons in vitro with potencies comparable to VEGFB. Similar to VEGFB, Vefins were not mitogenic for MCF-7 cancer cells. Furthermore, one of the peptides, Vefin7, even dose-dependently inhibited the proliferation of MCF-7 cells in vitro. Unraveling the neurotrophic and neuroprotective potentials of VEGFB, the only nonangiogenic factor of the VEGF family, is promising for the development of neuroprotective peptide-based therapies.


Assuntos
Fator B de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Sistema Nervoso Central , Neurônios , Peptídeos/farmacologia
14.
Ugeskr Laeger ; 182(3)2020 01 13.
Artigo em Dinamarquês | MEDLINE | ID: mdl-32052730

RESUMO

In recent years, gene therapy has resurged as a potential treatment for an increasing number of medical diseases including those affecting the central nervous system (CNS), which is discussed in this review. Clinical trials have revealed promising results particularly in gene therapy for Parkinson's disease with upregulation of dopamine synthesis or downregulation of huntingtin synthesis in Huntington's disease. Gene therapy for spinal motor atrophy has received FDA approval this year. The biggest success is seen in ophthalmology, where gene therapy has been FDA/EU-approved for retinitis pigmentosa, sparking further hope of use for other CNS diseases in a near future.


Assuntos
Doenças do Sistema Nervoso Central , Doença de Huntington , Doença de Parkinson , Sistema Nervoso Central , Doenças do Sistema Nervoso Central/genética , Doenças do Sistema Nervoso Central/terapia , Terapia Genética , Humanos , Doença de Parkinson/genética , Doença de Parkinson/terapia
15.
Ann Anat ; 227: 151419, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31563570

RESUMO

BACKGROUND: Neuropeptide Y (NPY) plays a crucial role in many neurobiological functions, such as cognition and memory. Cognitive and memory impairment have been described in diabetic patients. The metabolism of NPY is determined by the activity of proteases, primarily dipeptidyl-peptidase-IV (DPP-IV). Therefore, DPP-IV inhibitors, such as sitagliptin, may modulate the function of NPY. In this study, we investigated the effect of type 1 diabetes and sitagliptin treatment on the regulation of the mRNA encoding for NPY and its receptors (Y1, Y2, and Y5 receptors) in the hippocampus. METHODS: Type 1 diabetes was induced in male Wistar rats by i.p. injection of streptozotocin. Starting two weeks after diabetes onset, animals were treated orally with sitagliptin (5mg/kg, daily) for two weeks. The mRNA expression of Npy and its receptors (Npy1r, Npy2r, and Npy5r) in the hippocampus was evaluated using in situ hybridization with 33P-labeled oligonucleotides. RESULTS: The mRNA expression of Npy, Npy1r and Npy5r was higher in the dentate gyrus, whereas Npy2r highest level was observed in the CA3 subregion. The mRNA expression of Npy, Npy1r and Npy5r in dentate gyrus, CA1 and CA3 was not affected by diabetes and/or by sitagliptin treatment. Type 1 diabetes increased the mRNA expression of Npy2r in the CA3 subregion, which was prevented by sitagliptin treatment. CONCLUSIONS: Our results show that type 1 diabetes, at early stages, induces mild changes in the NPY system in the hippocampus that were counteracted by sitagliptin treatment.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 1/fisiopatologia , Neuropeptídeo Y/genética , RNA Mensageiro/metabolismo , Análise de Variância , Animais , Glicemia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Neuropeptídeo Y/efeitos dos fármacos , Neuropeptídeo Y/fisiologia , Sondas de Oligonucleotídeos , Distribuição Aleatória , Ratos , Ratos Wistar , Fosfato de Sitagliptina/farmacologia , Fosfato de Sitagliptina/uso terapêutico
16.
Brain Res ; 1727: 146538, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31705862

RESUMO

The surging obesity epidemic calls for a deeper understanding of central nervous system (CNS) mechanisms underlying the biologically defended level of body weight. Here, we analyzed global gene expression in four hypothalamic and two brainstem nuclei involved in energy homeostatic control of body weight in diet-induced obese (DIO) and lean rats. Male Sprague-Dawley rats were offered ad libitum chow, or a two-choice diet consisting of a high palatable high sugar/fat diet and chow for 40 weeks. At termination, the hypothalamic arcuate nucleus (ARC), dorsomedial hypothalamus (DMH), paraventricular nucleus (PVN) and lateral hypothalamus area (LHA), as well as the brainstem area postrema (AP) and nucleus of the solitary tract (NTS), were isolated by laser capture microdissection (LCM) followed by mRNA sequencing. Global gene expression analyses revealed a total of 88 differentially expressed genes (DEGs) in DIO rats. Transcriptome changes were mainly observed in the DMH and NTS and associated with neuropeptide signaling and regulation of signaling transduction pathways, suggesting a key role of these brain regions in body weight regulation.


Assuntos
Núcleo Hipotalâmico Dorsomedial/metabolismo , Obesidade/genética , Núcleo Solitário/metabolismo , Transcriptoma , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Masculino , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
17.
Sci Rep ; 9(1): 19393, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852985

RESUMO

In epilepsy patients, drug-resistant seizures often originate in one of the temporal lobes. In selected cases, when certain requirements are met, this area is surgically resected for therapeutic reasons. We kept the resected tissue slices alive in vitro for 48 h to create a platform for testing a novel treatment strategy based on neuropeptide Y (NPY) against drug-resistant epilepsy. We demonstrate that NPY exerts a significant inhibitory effect on epileptiform activity, recorded with whole-cell patch-clamp, in human hippocampal dentate gyrus. Application of NPY reduced overall number of paroxysmal depolarising shifts and action potentials. This effect was mediated by Y2 receptors, since application of selective Y2-receptor antagonist blocked the effect of NPY. This proof-of-concept finding is an important translational milestone for validating NPY-based gene therapy for targeting focal drug-resistant epilepsies, and increasing the prospects for positive outcome in potential clinical trials.


Assuntos
Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia do Lobo Temporal/tratamento farmacológico , Neuropeptídeo Y/administração & dosagem , Receptores de Neuropeptídeo Y/genética , Potenciais de Ação/efeitos dos fármacos , Adulto , Giro Denteado/diagnóstico por imagem , Giro Denteado/efeitos dos fármacos , Giro Denteado/fisiopatologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Humanos , Síndrome de Landau-Kleffner/tratamento farmacológico , Síndrome de Landau-Kleffner/fisiopatologia , Síndrome de Landau-Kleffner/cirurgia , Masculino , Pessoa de Meia-Idade , Técnicas de Patch-Clamp , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Transmissão Sináptica/efeitos dos fármacos
18.
Mol Ther Methods Clin Dev ; 15: 179-193, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31660420

RESUMO

Gene therapy has been suggested as a plausible novel approach to achieve seizure control in patients with focal epilepsy that do not adequately respond to pharmacological treatment. We investigated the seizure-suppressant potential of combinatorial neuropeptide Y and Y2 receptor single vector gene therapy based on adeno-associated virus serotype 1 (AAV1) in rats. First, a dose-response study in the systemic kainate-induced acute seizure model was performed, whereby the 1012 genomic particles (gp)/mL titer of the vector was selected as an optimal concentration. Second, an efficacy study was performed in the intrahippocampal kainate chronic model of spontaneous recurrent seizures (SRSs), designed to reflect a likely clinical scenario, with magnetic resonance image (MRI)-guided focal unilateral administration of the vector in the hippocampus during the chronic stage of the disease. The efficacy study demonstrated a favorable outcome of the gene therapy, with a 31% responder rate (more than 50% reduction in SRS frequency) and 13% seizure-freedom rate, whereas no such effects were observed in the control animals. The inter-SRS and SRS cluster intervals were also significantly prolonged in the treated group compared to controls. In addition, the SRS duration was significantly reduced in the treated group but not in the controls. This study establishes the SRS-suppressant ability of the single vector combinatorial neuropeptide Y/Y2 receptor gene therapy in a clinically relevant chronic model of epilepsy.

20.
Neurobiol Aging ; 81: 88-101, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31255922

RESUMO

Neurodegenerative disorders such as Alzheimer's disease (AD) are characterized by the irreversible neuronal loss and memory impairment, and current treatments are merely symptomatic. Erythropoietin (EPO) has been shown to possess neurotrophic, neuroprotective, anti-inflammatory, and memory-enhancing effects, which could be therapeutically beneficial in the different aspects of AD. However, the hematopoietic effect of EPO has hampered its potential as a neuroprotective and procognitive agent. In this study, we characterized a novel small peptide, NL100, derived from a conserved C-helix region of EPO. NL100 was shown to bind to the EPO receptor, induce neuritogenesis, and protect hippocampal neurons from oxidative- and Aß25-35-induced neurodegeneration in vitro. Importantly, long-term NL100 treatment did not induce hematopoiesis, overcoming this challenge associated with EPO. Memory-enhancing effects were demonstrated after NL100 treatment in social recognition test for short-term memory, in both healthy rats and rats challenged centrally with Aß25-35 peptide, and in the Morris water maze test for spatial memory. Moreover, NL100 was shown to reverse Aß25-35-induced hippocampal degeneration and gliosis as well as pilocarpine-induced suppression of long-term potentiation in rats. In conclusion, NL100 is a novel EPO-derived nonhematopoietic peptide with neuroprotective and memory-enhancing effects and could therefore be a potential candidate for the development of new treatments for neurodegenerative disorders and dementia.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Demência/tratamento farmacológico , Demência/etiologia , Eritropoetina , Potenciação de Longa Duração/efeitos dos fármacos , Memória/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/etiologia , Fármacos Neuroprotetores , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Animais , Eritropoetina/química , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos Endogâmicos BALB C , Crescimento Neuronal/efeitos dos fármacos , Ratos Sprague-Dawley , Ratos Wistar
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