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1.
Biochemistry (Mosc) ; 89(Suppl 1): S34-S56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38621743

RESUMO

Mutations that disrupt the function of the DNA/RNA-binding protein FUS could cause amyotrophic lateral sclerosis (ALS) and other neurodegenerative diseases. One of the key features in ALS pathogenesis is the formation of insoluble protein aggregates containing aberrant isoforms of the FUS protein in the cytoplasm of upper and lower motor neurons. Reproduction of human pathology in animal models is the main tool for studying FUS-associated pathology and searching for potential therapeutic agents for ALS treatment. In this review, we provide a systematic analysis of the role of FUS protein in ALS pathogenesis and an overview of the results of modelling FUS-proteinopathy in animals.


Assuntos
Esclerose Lateral Amiotrófica , Animais , Humanos , Esclerose Lateral Amiotrófica/genética , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Citoplasma/metabolismo , Mutação , Modelos Animais de Doenças
2.
Eur J Immunol ; 54(3): e2350664, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38088236

RESUMO

COVID-19 is a systemic inflammatory disease initiated by SARS-CoV-2 virus infection. Multiple vaccines against the Wuhan variant of SARS-CoV-2 have been developed including a whole virion beta-propiolactone-inactivated vaccine based on the B.1.1 strain (CoviVac). Since most of the population has been vaccinated by targeting the original or early variants of SARS-CoV-2, the emergence of novel mutant variants raises concern over possible evasion of vaccine-induced immune responses. Here, we report on the mechanism of protection by CoviVac, a whole virion-based vaccine, against the Omicron variant. CoviVac-immunized K18-hACE2 Tg mice were protected against both prototype B.1.1 and BA.1-like (Omicron) variants. Subsequently, vaccinated K18-hACE2 Tg mice rapidly cleared the infection via cross-reactive T-cell responses and cross-reactive, non-neutralizing antibodies recognizing the Omicron variant Spike protein. Thus, our data indicate that efficient protection from SARS-CoV-2 variants can be achieved by the orchestrated action of cross-reactive T cells and non-neutralizing antibodies.


Assuntos
COVID-19 , Melfalan , SARS-CoV-2 , gama-Globulinas , Animais , Humanos , Camundongos , Vacinas de Produtos Inativados , Formação de Anticorpos , COVID-19/prevenção & controle , Linfócitos T , Vírion , Anticorpos Amplamente Neutralizantes , Anticorpos Neutralizantes , Anticorpos Antivirais
3.
Molecules ; 28(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005288

RESUMO

Currently, there are no effective drugs for the treatment of amyotrophic lateral sclerosis (ALS). Only two drugs-edaravone and riluzole-have been approved, but they have very limited efficacy. The aim of this work was to modify the structural core of the Edaravone-phenylpyrazolone moiety and combine it with aminoadamantane pharmacophore in order to expand the spectrum of its action to a number of processes involved in the pathogenesis of ALS. New conjugates of edaravone derivatives with 1-aminoadamantanes combined with alkylene or hydroxypropylene spacers were synthesized, and their biological activity was investigated. Compounds were found that could inhibit lipid peroxidation and calcium-related mitochondrial permeability, block fast sodium currents of CNS neurons, and reduce aggregation of the mutated form of the FUS-protein typical to ALS. So, the proposed modification of the edaravone molecule has allowed the obtaining of new original structures that combine some prospective therapeutic mechanisms against key chains of the pathogenesis of ALS. The identified lead compounds can be used for further optimization and development of new promising drugs on this basis for the treatment of ALS.


Assuntos
Adamantano , Esclerose Lateral Amiotrófica , Fármacos Neuroprotetores , Humanos , Edaravone/farmacologia , Edaravone/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Esclerose Lateral Amiotrófica/tratamento farmacológico , Riluzol , Amantadina/uso terapêutico
4.
Biomedicines ; 11(4)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37189768

RESUMO

Evident similarities in pathological features in aging and Alzheimer's disease (AD) raise the question of a role for natural age-related adaptive mechanisms in the prevention/elimination of disturbances in interrelations between different brain areas. In our previous electroencephalogram (EEG) studies on 5xFAD- and FUS-transgenic mice, as models of AD and amyotrophic lateral sclerosis (ALS), this suggestion was indirectly confirmed. In the current study, age-related changes in direct EEG synchrony/coherence between the brain structures were evaluated. METHODS: In 5xFAD mice of 6-, 9-, 12-, and 18-month ages and their wild-type (WT5xFAD) littermates, we analyzed baseline EEG coherence between the cortex, hippocampus/putamen, ventral tegmental area, and substantia nigra. Additionally, EEG coherence between the cortex and putamen was analyzed in 2- and 5-month-old FUS mice. RESULTS: In the 5xFAD mice, suppressed levels of inter-structural coherence vs. those in WT5xFAD littermates were observed at ages of 6, 9, and 12 months. In 18-month-old 5xFAD mice, only the hippocampus ventral tegmental area coherence was significantly reduced. In 2-month-old FUS vs. WTFUS mice, the cortex-putamen coherence suppression, dominated in the right hemisphere, was observed. In 5-month-old mice, EEG coherence was maximal in both groups. CONCLUSION: Neurodegenerative pathologies are accompanied by the significant attenuation of intracerebral EEG coherence. Our data are supportive for the involvement of age-related adaptive mechanisms in intracerebral disturbances produced by neurodegeneration.

5.
Int J Mol Sci ; 24(9)2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37175876

RESUMO

Proteasomes degrade most intracellular proteins. Several different forms of proteasomes are known. Little is known about the role of specific proteasome forms in the central nervous system (CNS). Inhibitors targeting different proteasome forms are used in clinical practice and were shown to modulate long-term potentiation (LTP) in hippocampal slices of untreated animals. Here, to address the role of non-constitutive proteasomes in hippocampal synaptic plasticity and reveal the consequences of their continuous inhibition, we studied the effect of chronic administration of the non-constitutive proteasome inhibitor ONX-0914 on the LTP induced by two different protocols: tetanic stimulation and theta-burst stimulation (TBS). Both the tetanus- and TBS-evoked potentiation contribute to the different forms of hippocampal-dependent memory and learning. Field-excitatory postsynaptic potentials (fEPSPs) in hippocampal slices from control animals and animals treated with DMSO or ONX-0914 were compared. LTP induced by the TBS was not affected by ONX-0914 administration; however, chronic injections of ONX-0914 led to a decrease in fEPSP slopes after tetanic stimulation. The observed effects correlated with differential expression of genes involved in synaptic plasticity, glutaminergic synapse, and synaptic signaling. Obtained results indicate that non-constitutive proteasomes are likely involved in the tetanus-evoked LTP, but not the LTP occurring after TBS, supporting the relevance and complexity of the role of specific proteasomes in synaptic plasticity, memory, and learning.


Assuntos
Potenciação de Longa Duração , Tétano , Ratos , Camundongos , Animais , Inibidores de Proteassoma/farmacologia , Ratos Sprague-Dawley , Complexo de Endopeptidases do Proteassoma/metabolismo , Tétano/metabolismo , Hipocampo/metabolismo , Expressão Gênica , Glutamatos/metabolismo , Estimulação Elétrica
6.
Nucleic Acids Res ; 51(11): 5810-5830, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37115004

RESUMO

Dysfunction of the RNA-binding protein (RBP) FUS implicated in RNA metabolism can cause amyotrophic lateral sclerosis (ALS) and other neurodegenerative diseases. Mutations affecting FUS nuclear localization can drive RNA splicing defects and stimulate the formation of non-amyloid inclusions in affected neurons. However, the mechanism by which FUS mutations contribute to the development of ALS remains uncertain. Here we describe a pattern of RNA splicing changes in the dynamics of the continuous proteinopathy induced by mislocalized FUS. We show that the decrease in intron retention of FUS-associated transcripts represents the hallmark of the pathogenesis of ALS and is the earliest molecular event in the course of progression of the disease. As FUS aggregation increases, the pattern of RNA splicing changes, becoming more complex, including a decrease in the inclusion of neuron-specific microexons and induction of cryptic exon splicing due to the sequestration of additional RBPs into FUS aggregates. Crucially, the identified features of the pathological splicing pattern are also observed in ALS patients in both sporadic and familial cases. Our data provide evidence that both a loss of nuclear FUS function due to mislocalization and the subsequent cytoplasmic aggregation of mutant protein lead to the disruption of RNA splicing in a multistep fashion during FUS aggregation.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Neurônios Motores/metabolismo , Mutação , Splicing de RNA/genética , Proteína FUS de Ligação a RNA/metabolismo
8.
Molecules ; 27(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36500504

RESUMO

Linked to Alzheimer's disease (AD), amyloids and tau-protein are known to contain a large number of cysteine (Cys) residues. In addition, certain levels of some common biogenic thiols (cysteine (Cys), homocysteine (Hcy), glutathione (GSH), etc.) in biological fluids are closely related to AD as well as other diseases. Therefore, probes with a selective interaction with the above-mentioned thiols can be used for the monitoring and visualizing changes of (bio)thiols in the biological fluids as well as in the brain of animal models of Alzheimer's disease. In this study, new Eu(III), Tb(III), Gd(III) and Sm(III) complexes of 2,2'-bipyridine ligands containing TEMPO fragments as receptor units for (bio)thiols are reported. The presence of free radical fragments of the ligand in the complexes was proved by using the electronic paramagnetic resonance (EPR) method. Among all the complexes, the Eu(III) complex turned out to be the most promising one as luminescence- and spin-probe for the detection of biogenic thiols. The EPR and fluorescent titration methods showed the interaction of the resulting complex with free Cys and GSH in solution. To study the practical applicability of the probes for the monitoring of AD in-vivo, by using the above-mentioned Eu(III)-based probe, the staining of the brain of mice with amyloidosis and Vero cell cultures supplemented with the cysteine-enriched medium was studied as well as the fluorescence titration of Bovine Serum Albumin, BSA (as the model for the thiol moieties containing protein), was carried out. Based on the results of fluorescence titration, the formation of a non-covalent inclusion complex between the above-mentioned Eu(III) complex and BSA was suggested.


Assuntos
2,2'-Dipiridil , Doença de Alzheimer , Animais , Camundongos , Cisteína , Fluorescência , Soroalbumina Bovina/química , Ligantes , Compostos de Sulfidrila , Glutationa , Corantes Fluorescentes/química
9.
Biomedicines ; 10(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36140378

RESUMO

Parkinson's disease (PD) is one of the key neurodegenerative disorders caused by a dopamine deficiency in the striatum due to the death of dopaminergic (DA) neurons of the substantia nigra pars compacta. The initially discovered A53T mutation in the alpha-synuclein gene was linked to the formation of cytotoxic aggregates: Lewy bodies in the DA neurons of PD patients. Further research has contributed to the discovery of beta- and gamma-synucleins, which presumably compensate for the functional loss of either member of the synuclein family. Here, we review research from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity models and various synuclein-knockout animals. We conclude that the differences in the sensitivity of the synuclein-knockout animals compared with the MPTP neurotoxin are due to the ontogenetic selection of early neurons followed by a compensatory effect of beta-synuclein, which optimizes dopamine capture in the synapses. Triple-knockout synuclein studies have confirmed the higher sensitivity of DA neurons to the toxic effects of MPTP. Nonetheless, beta-synuclein could modulate the alpha-synuclein function, preventing its aggregation and loss of function. Overall, the use of knockout animals has helped to solve the riddle of synuclein functions, and these proteins could be promising molecular targets for the development of therapies that are aimed at optimizing the synaptic function of dopaminergic neurons.

10.
Molecules ; 27(7)2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35408484

RESUMO

Cell culturing methods in its classical 2D approach have limitations associated with altered cell morphology, gene expression patterns, migration, cell cycle and proliferation. Moreover, high throughput drug screening is mainly performed on 2D cell cultures which are physiologically far from proper cell functions resulting in inadequate hit-compounds which subsequently fail. A shift to 3D culturing protocols could solve issues with altered cell biochemistry and signaling which would lead to a proper recapitulation of physiological conditions in test systems. Here, we examined porous ultra-high molecular weight polyethylene (UHMWPE) as an inexpensive and robust material with varying pore sizes for cell culturing. We tested and developed culturing protocols for immortalized human neuroblastoma and primary mice hippocampal cells which resulted in high rate of cell penetration within one week of cultivation. UHMWPE was additionally functionalized with gelatin, poly-L-lysine, BSA and chitosan, resulting in increased cell penetrations of the material. We have also successfully traced GFP-tagged cells which were grown on a UHMWPE sample after one week from implantation into mice brain. Our findings highlight the importance of UHMWPE use as a 3D matrix and show new possibilities arising from the use of cheap and chemically homogeneous material for studying various types of cell-surface interactions further improving cell adhesion, viability and biocompatibility.


Assuntos
Técnicas de Cultura de Células , Polietilenos , Animais , Técnicas de Cultura de Células/métodos , Células Cultivadas , Camundongos , Peso Molecular , Polietileno/química , Polietilenos/química , Porosidade
11.
J Alzheimers Dis ; 81(4): 1429-1443, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935079

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is characterized by degeneration of motor neurons resulting in muscle atrophy. In contrast to the lower motor neurons, the role of upper (cortical) neurons in ALS is yet unclear. Maturation of locomotor networks is supported by dopaminergic (DA) projections from substantia nigra to the spinal cord and striatum. OBJECTIVE: To examine the contribution of DA mediation in the striatum-cortex networks in ALS progression. METHODS: We studied electroencephalogram (EEG) from striatal putamen (Pt) and primary motor cortex (M1) in ΔFUS(1-359)-transgenic (Tg) mice, a model of ALS. EEG from M1 and Pt were recorded in freely moving young (2-month-old) and older (5-month-old) Tg and non-transgenic (nTg) mice. EEG spectra were analyzed for 30 min before and for 60 min after systemic injection of a DA mimetic, apomorphine (APO), and saline. RESULTS: In young Tg versus nTg mice, baseline EEG spectra in M1 were comparable, whereas in Pt, beta activity in Tg mice was enhanced. In older Tg versus nTg mice, beta dominated in EEG from both M1 and Pt, whereas theta and delta 2 activities were reduced. In younger Tg versus nTg mice, APO increased theta and decreased beta 2 predominantly in M1. In older mice, APO effects in these frequency bands were inversed and accompanied by enhanced delta 2 and attenuated alpha in Tg versus nTg mice. CONCLUSION: We suggest that revealed EEG modifications in ΔFUS(1-359)-transgenic mice are associated with early alterations in the striatum-cortex interrelations and DA transmission followed by adaptive intracerebral transformations.


Assuntos
Esclerose Lateral Amiotrófica/fisiopatologia , Apomorfina/farmacologia , Córtex Cerebral/fisiopatologia , Corpo Estriado/fisiopatologia , Agonistas de Dopamina/farmacologia , Animais , Córtex Cerebral/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Modelos Animais de Doenças , Eletroencefalografia , Masculino , Camundongos , Camundongos Transgênicos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia
12.
Neurobiol Aging ; 91: 76-87, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32224067

RESUMO

The etiology and pathogenesis of Parkinson's disease (PD) are tightly linked to the gain-of-function of α-synuclein. However, gradual accumulation of α-synuclein aggregates in dopaminergic neurons of substantia nigra pars compacta (SNpc) leads to the depletion of the functional pool of soluble α-synuclein, and therefore, creates loss-of-function conditions, particularly in presynaptic terminals of these neurons. Studies of how this late-onset depletion of a protein involved in many important steps of neurotransmission contributes to PD progression and particularly, to worsening the nigrostriatal pathology at late stages of the disease are limited and obtained data, are controversial. Recently, we produced a mouse line for conditional knockout of the gene encoding α-synuclein, and here we used its tamoxifen-inducible pan-neuronal inactivation to study consequences of the adult-onset (from the age of 6 months) and late-onset (from the age of 12 months) α-synuclein depletion to the nigrostriatal system. No significant changes of animal balance/coordination, the number of dopaminergic neurons in the SNpc and the content of dopamine and its metabolites in the striatum were observed after adult-onset α-synuclein depletion, but in aging (18-month-old) late-onset depleted mice we found a significant reduction of major dopamine metabolites without changes to the content of dopamine itself. Our data suggest that this might be caused, at least partially, by reduced expression of aldehyde dehydrogenase ALDH1a1 and could lead to the accumulation of toxic intermediates of dopamine catabolism. By extrapolating our findings to a potential clinical situation, we suggest that therapeutic downregulation of α-synuclein expression in PD patients is a generally safe option as it should not cause adverse side effects on the functionality of their nigrostriatal system. However, if started in aged patients, this type of therapy might trigger slight functional changes of the nigrostriatal system with potentially unwanted additive effect to already existing pathology.


Assuntos
Envelhecimento/genética , Envelhecimento/patologia , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Técnicas de Inativação de Genes , Doença de Parkinson/etiologia , Doença de Parkinson/genética , Substância Negra/metabolismo , Substância Negra/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Família Aldeído Desidrogenase 1/genética , Família Aldeído Desidrogenase 1/metabolismo , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Regulação para Baixo , Expressão Gênica/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Terapia de Alvo Molecular , Doença de Parkinson/terapia , Retinal Desidrogenase/genética , Retinal Desidrogenase/metabolismo , Transmissão Sináptica/genética
13.
Neurochem Res ; 45(5): 1168-1179, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32157564

RESUMO

A number of mutations in a gene encoding RNA-binding protein FUS have been linked to the development of a familial form of amyotrophic lateral sclerosis known as FUS-ALS. C-terminal truncations of FUS by either nonsense or frameshift mutations lead to the development of FUS-ALS with a particularly early onset and fast progression. However, even in patients bearing these highly pathogenic mutations the function of motor neurons is not noticeably compromised for at least a couple of decades, suggesting that until cytoplasmic levels of FUS lacking its C-terminal nuclear localisation signal reaches a critical threshold, motor neurons are able to tolerate its permanent production. In order to identify how the nervous system responds to low levels of pathogenic variants of FUS we produced and characterised a mouse line, L-FUS[1-359], with a low neuronal expression level of a highly aggregation-prone and pathogenic form of C-terminally truncated FUS. In contrast to mice that express substantially higher level of the same FUS variant and develop severe early onset motor neuron pathology, L-FUS[1-359] mice do not develop any clinical or histopathological signs of motor neuron deficiency even at old age. Nevertheless, we detected substantial changes in the spinal cord transcriptome of these mice compared to their wild type littermates. We suggest that at least some of these changes reflect activation of cellular mechanisms compensating for the potentially damaging effect of pathogenic FUS production. Further studies of these mechanism might reveal effective targets for therapy of FUS-ALS and possibly, other forms of ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Doenças Assintomáticas , Perfilação da Expressão Gênica/métodos , Proteína FUS de Ligação a RNA/biossíntese , Medula Espinal/metabolismo , Transcriptoma/fisiologia , Esclerose Lateral Amiotrófica/genética , Animais , Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Proteína FUS de Ligação a RNA/genética
14.
J Photochem Photobiol B ; 202: 111722, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31785445

RESUMO

Nowadays, the study of well-known sensitizers for photodynamic therapy and search for new ones are intensively conducted. In the present work supramolecular organization of crown-ether and phosphoryl-containing phthalocyanines ({Mgcr8Pc, I, and М[R4Pc] (M = Zn2+, R = -OPhP(O)(OH)(OC5H11), II; M = 2H+, R = -OPhP(O)(OH)(OC5H11), III; M = 2H+, -OPhP(O)(OH)2), IIIa}, respectively) was studied in microheterogeneous media. The role of a metal ion of a macrocycle in monomerization of phosphoryl-containing Pc in the presence of water-soluble poly(N-vinylpyrrolidone) was revealed. Some photobiological properties of compound I as possible photosensitizer with respect to human adenocarcinoma cells, HeLa, were analyzed. So, the light and dark cytotoxicity of I (IC50 dose) was 1.83 µÐœ and higher than 25 µÐœ, respectively. The reactive oxygen species (ROS) formation studied with use of fluorescent ROS detector DCFH2 revealed the plateau on the curves of fluorescence intensity vs time after 30 min of irradiation and ROS are almost not produced after the end of irradiation. In HeLa cells, accumulation of compounds I and II as well as fluorescent DCF presence were shown by confocal microscopic images. At concentration of 5 µM, compound I easily penetrates into the cell localizing primarily in the perinuclear region, whereas compound II mainly remains in the periphery of the cells in the fluorescent-active state. The results obtained allow us to continue the study of these interesting compounds.


Assuntos
Éteres de Coroa/química , Indóis/química , Metais/química , Fármacos Fotossensibilizantes/química , Polivinil/química , Pirrolidinas/química , Espécies Reativas de Oxigênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Isoindóis , Luz , Microscopia Confocal , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/farmacologia
15.
Mol Neurobiol ; 57(1): 191-199, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31515692

RESUMO

A series of new positive allosteric modulators (PAMs) of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors based on 3,7-diazabicyclo[3.3.1]nonane scaffold have been designed, synthesized, and analyzed. In electrophysiological patch clamp studies, several compounds have demonstrated a sub-nanomolar potency. Compound 4 in in vivo tests showed anti-amnestic properties in the scopolamine-induced model of amnesia in the step-through passive avoidance or maximal electroshock experiments in rats at 0.01 mg/kg showing a significant "dose-response" advantage over memantine. Based on the analysis of the flexible docking results of PAMs, the cyclothiazide-like mechanism of binding mode was suggested as the major site for the interaction with AMPA receptors.


Assuntos
Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/efeitos dos fármacos , Receptores de AMPA/metabolismo , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico/farmacologia , Regulação Alostérica/efeitos dos fármacos , Animais , Benzotiadiazinas/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/metabolismo , Masculino , Ratos Wistar
16.
J Alzheimers Dis ; 70(1): 241-256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31177214

RESUMO

Cognitive malfunction, synaptic dysfunction, and disconnections in neural networks are core deficits in Alzheimer's disease (AD). 5xFAD mice, a transgenic model of AD, are characterized by an enhanced level of amyloid-ß and abnormal neurotransmission. The dopaminergic (DA) system has been shown to be involved in amyloid-ß transformations and neuronal plasticity; however, its role in functional network changes in familial AD still remains unclear. In 5xFAD and non-transgenic freely moving mice, electroencephalograms (EEGs) were simultaneously recorded from the secondary motor cortex (MC), superficial layers of the hippocampal CA1 area (HPC), substantia nigra (SN), and ventral tegmental area (VTA). EEGs and their frequency spectra were analyzed before and after systemic injection of a DA receptor agonist, apomorphine (APO). In the baseline EEG from MC and HPC of 5xFAD mice, delta and alpha oscillations were enhanced and beta activity was attenuated, compared to control mice. In VTA and SN of 5xFAD mice, delta-theta activity was decreased and beta oscillations dominated. In control mice, APO suppressed delta activity in VTA to a higher extent than in MC, whereas in 5xFAD mice, this difference was eliminated due to attenuation of the delta suppression in VTA. APO increased beta activity in MC of mice from both groups while significant beta suppression was observed in VTA of 5xFAD mice. These mice were characterized by significant decrease of tyrosine hydroxylase immunopositive cells in both VTA and SN and of DA transporter in MC and hippocampal dentate gyrus. We suggest that the EEG modifications observed in 5xFAD mice are associated with alterations in dopaminergic transmission, resulting in adaptive changes in the cerebral networks in the course of familial AD development.


Assuntos
Doença de Alzheimer/patologia , Apomorfina/farmacologia , Encéfalo/efeitos dos fármacos , Agonistas de Dopamina/farmacologia , Neurônios Dopaminérgicos/patologia , Mesencéfalo/patologia , Doença de Alzheimer/fisiopatologia , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Eletroencefalografia , Masculino , Mesencéfalo/fisiopatologia , Camundongos , Camundongos Transgênicos
17.
Curr Neuropharmacol ; 17(3): 288-294, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30227819

RESUMO

Alzheimer's disease (AD) is characterized by the loss of neurons. It is the most common cause of dementia in the elderly population accompanied by pathological degeneration of neurofibrillary tangles. Senile plaques are formed with beta-amyloid, hyperphosphoryled tau protein, apolipoprotein E and presenilin associated with protease activity [amyloid beta (Aß), gamma-secretase (γS)]. The molecular mechanisms of neurodegeneration include apoptosis, oxidative stress (free radical generation), inflammation, immune activation, and others. The lack of effective treatments for AD stems mainly from the incomplete understanding the causes of AD. Currently, there are several hypotheses explaining the early mechanisms of AD pathogenesis. Recent years witnessed an unprecedented research growth in the area of nanotechnology, which uses atomic, molecular and macromolecular methods to create products in microscale (nanoscale) dimensions. In this article, we have discussed the role of nanotechnology in the development and improvement of techniques for early diagnosis and effective treatment of AD. Since AD pathology is practically irreversible, applications of disease-modifying treatments could be successful only if early diagnosis of AD is available. This review highlights various possibilities for the early diagnosis and therapy of AD and investigates potential adaptation of nanoparticles-dendrimers as a class of well-defined branched polymers that are chemically synthesized with a well-defined shape, size and nanoscopic physicochemical properties reminiscent of the proteins for the treatment of neurodegenerative diseases.


Assuntos
Doença de Alzheimer/terapia , Antipsicóticos/uso terapêutico , Dendrímeros/uso terapêutico , Animais , Dendrímeros/química , Humanos , Nanopartículas/química , Nanopartículas/uso terapêutico
18.
Neurogenetics ; 19(3): 189-204, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29982879

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder that leads to the eventual death of motor neurons. Described cases of familial ALS have emphasized the significance of protein misfolding and aggregation of two functionally related proteins, FUS (fused in sarcoma) and TDP-43, implicated in RNA metabolism. Herein, we performed a comprehensive analysis of the in vivo model of FUS-mediated proteinopathy (ΔFUS(1-359) mice). First, we used the Noldus CatWalk system and confocal microscopy to determine the time of onset of the first clinical symptoms and the appearance of FUS-positive inclusions in the cytoplasm of neuronal cells. Second, we applied RNA-seq to evaluate changes in the gene expression profile encompassing the pre-symptomatic and the symptomatic stages of disease progression in motor neurons and the surrounding microglia of the spinal cord. The resulting data show that FUS-mediated proteinopathy is virtually asymptomatic in terms of both the clinical symptoms and the molecular aspects of neurodegeneration until it reaches the terminal stage of disease progression (120 days from birth). After this time, the pathological process develops very rapidly, resulting in the formation of massive FUS-positive inclusions accompanied by a transcriptional "burst" in the spinal cord cells. Specifically, it manifests in activation of a pro-inflammatory phenotype of microglial cells and malfunction of acetylcholine synapse transmission in motor neurons. Overall, we assume that the highly reproducible course of the pathological process, as well as the described accompanying features, makes ΔFUS(1-359) mice a convenient model for testing potential therapeutics against proteinopathy-induced decay of motor neurons.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Modelos Animais de Doenças , Camundongos Transgênicos , Proteína FUS de Ligação a RNA/genética , Animais , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Camundongos , Neurônios Motores/fisiologia , Deficiências na Proteostase/genética , Deficiências na Proteostase/metabolismo , Deficiências na Proteostase/patologia , Transdução de Sinais/genética , Medula Espinal/metabolismo , Medula Espinal/patologia
19.
CNS Neurol Disord Drug Targets ; 17(8): 604-607, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30047337

RESUMO

BACKGROUND: It was previously shown that inactivation of gamma-synuclein which is a small soluble neuronal protein affects psycho-emotional status and cognitive abilities in knock-out mice. OBJECTIVE: Determine the role of gamma-synuclein inactivation on memory performance in aging animals. METHOD: We used the passive avoidance test and acute amphetamine administration in aging gammasynuclein knock-out mice. RESULTS: As a result, we found moderate aging-unlinked deficit of dopaminergic neurotransmitter system of gamma-synuclein knock-out mice. At the same time, the evidence of progressive synaptic vesicle trafficking machinery impairment was obtained. CONCLUSION: Therefore most likely these dysfunctions are associated with a reduction in the highefficient learning performance in tests that require intact working memory.


Assuntos
Envelhecimento/genética , Dopamina/metabolismo , Transtornos da Memória/genética , Memória de Curto Prazo/fisiologia , gama-Sinucleína/deficiência , Anfetamina/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Modelos Animais de Doenças , Dopaminérgicos/farmacologia , Locomoção/efeitos dos fármacos , Locomoção/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , gama-Sinucleína/genética
20.
Curr Med Chem ; 25(39): 5315-5326, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27494393

RESUMO

Dimebon (or Latrepirdine) was initially used as an anti-histamergic drug but later new therapeutic properties were rediscovered, adding to a growing body of "old" agents with prominent neuroprotective effects. In the present manuscript, we are focusing on our latest study on Dimebon with regard to brain's pathological processes using in vivo proteinopathy models. In the study, neurodegenerative pathology has been attributed to a group of aggregate-prone proteins: hyperphosphorylated tau, fused in sarcoma and γ-synuclein , which are involved in a number of neurological disorders. We have also presented our in vitro model based on overexpression of an aberrant mutant form of transactive response DNA binding 43 kDa protein in cultured SH-SY5Y neuroblastoma cells. Dimebon treatment followed by the activation of autophagy markers resulted in reduced number of inclusion containing cells. The most significant effects of Dimebon appeared to be on the improving cellular energy balance, mitochondria stability by increasing the threshold for nonselective mitochondrial pore opening as well as on increased calcium retention capacity while reducing lipid peroxidation. The therapeutic potential of Dimebon and newly designed analogs show disease modifying properties and could be used to treat neurodegenerative disorders. In addition, new data hint on a possible anti-aging effect and potential application of Dimebon for treatment of anxiety, ischemia and depression. Overall, our findings suggest that the most pronounced effect of Dimebon was observed when treatment was started at the early stages of disease onset and this factor needs to be taken into account while planning future clinical trials.


Assuntos
Indóis/uso terapêutico , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Animais , Autofagia/efeitos dos fármacos , Humanos , Indóis/química , Indóis/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/metabolismo , Proteínas tau/genética , Proteínas tau/metabolismo
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