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1.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360787

RESUMO

The principal pathogenic event in Parkinson's disease is characterized by the conformational change of α-synuclein, which form pathological aggregates of misfolded proteins, and then accumulate in intraneuronal inclusions causing dopaminergic neuronal loss in specific brain regions. Over the last few years, a revolutionary theory has correlated Parkinson's disease and other neurological disorders with a shared mechanism, which determines α-synuclein aggregates and progresses in the host in a prion-like manner. In this review, the main characteristics shared between α-synuclein and prion protein are compared and the cofactors that influence the remodeling of native protein structures and pathogenetic mechanisms underlying neurodegeneration are discussed.


Assuntos
Doença de Parkinson , Doenças Priônicas , Agregados Proteicos , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Animais , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doenças Priônicas/metabolismo , Doenças Priônicas/patologia
2.
Int J Mol Sci ; 22(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34360942

RESUMO

The exact mechanism underlying selective dopaminergic neurodegeneration is not completely understood. The complex interplay among toxic alpha-synuclein aggregates, oxidative stress, altered intracellular Ca2+-homeostasis, mitochondrial dysfunction and disruption of mitochondrial integrity is considered among the pathogenic mechanisms leading to dopaminergic neuronal loss. We herein investigated the molecular mechanisms leading to mitochondrial dysfunction and its relationship with activation of the neuroinflammatory process occurring in Parkinson's disease. To address these issues, experiments were performed in vitro and in vivo in mice carrying the human mutation of α-synuclein A53T under the prion murine promoter. In these models, the expression and activity of NCX isoforms, a family of important transporters regulating ionic homeostasis in mammalian cells working in a bidirectional way, were evaluated in neurons and glial cells. Mitochondrial function was monitored with confocal microscopy and fluorescent dyes to measure mitochondrial calcium content and mitochondrial membrane potential. Parallel experiments were performed in 4 and 16-month-old A53T-α-synuclein Tg mice to correlate the functional data obtained in vitro with mitochondrial dysfunction and neuroinflammation through biochemical analysis. The results obtained demonstrated: 1. in A53T mice mitochondrial dysfunction occurs early in midbrain and later in striatum; 2. mitochondrial dysfunction occurring in the midbrain is mediated by the impairment of NCX3 protein expression in neurons and astrocytes; 3. mitochondrial dysfunction occurring early in midbrain triggers neuroinflammation later into the striatum, thus contributing to PD progression during mice aging.


Assuntos
Mesencéfalo/metabolismo , Mitocôndrias/metabolismo , Doença de Parkinson/metabolismo , Trocador de Sódio e Cálcio/metabolismo , alfa-Sinucleína/genética , Animais , Astrócitos/metabolismo , Cálcio/metabolismo , Células Cultivadas , Neurônios Dopaminérgicos/metabolismo , Mesencéfalo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação de Sentido Incorreto , Doença de Parkinson/genética , Trocador de Sódio e Cálcio/genética , alfa-Sinucleína/metabolismo
3.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361780

RESUMO

Parkinson's disease is characterized by the loss of dopaminergic neurons in substantia nigra pars compacta (SNpc) and the resultant loss of dopamine in the striatum. Various studies have shown that oxidative stress and neuroinflammation plays a major role in PD progression. In addition, the autophagy lysosome pathway (ALP) plays an important role in the degradation of aggregated proteins, abnormal cytoplasmic organelles and proteins for intracellular homeostasis. Dysfunction of ALP results in the accumulation of α-synuclein and the loss of dopaminergic neurons in PD. Thus, modulating ALP is becoming an appealing therapeutic intervention. In our current study, we wanted to evaluate the neuroprotective potency of noscapine in a rotenone-induced PD rat model. Rats were administered rotenone injections (2.5 mg/kg, i.p.,) daily followed by noscapine (10 mg/kg, i.p.,) for four weeks. Noscapine, an iso-qinulinin alkaloid found naturally in the Papaveraceae family, has traditionally been used in the treatment of cancer, stroke and fibrosis. However, the neuroprotective potency of noscapine has not been analyzed. Our study showed that administration of noscapine decreased the upregulation of pro-inflammatory factors, oxidative stress, and α-synuclein expression with a significant increase in antioxidant enzymes. In addition, noscapine prevented rotenone-induced activation of microglia and astrocytes. These neuroprotective mechanisms resulted in a decrease in dopaminergic neuron loss in SNpc and neuronal fibers in the striatum. Further, noscapine administration enhanced the mTOR-mediated p70S6K pathway as well as inhibited apoptosis. In addition to these mechanisms, noscapine prevented a rotenone-mediated increase in lysosomal degradation, resulting in a decrease in α-synuclein aggregation. However, further studies are needed to further develop noscapine as a potential therapeutic candidate for PD treatment.


Assuntos
Autofagia/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Noscapina/farmacologia , Doença de Parkinson Secundária/tratamento farmacológico , Doença de Parkinson Secundária/genética , Parte Compacta da Substância Negra/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Catalase/genética , Catalase/metabolismo , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/patologia , Parte Compacta da Substância Negra/metabolismo , Parte Compacta da Substância Negra/patologia , Ratos , Ratos Wistar , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Rotenona/toxicidade , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
4.
Int J Mol Sci ; 22(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199427

RESUMO

The interplay between α-synuclein and dopamine derivatives is associated with oxidative stress-dependent neurodegeneration in Parkinson's disease (PD). The formation in the dopaminergic neurons of intraneuronal inclusions containing aggregates of α-synuclein is a typical hallmark of PD. Even though the biochemical events underlying the aberrant aggregation of α-synuclein are not completely understood, strong evidence correlates this process with the levels of dopamine metabolites. In vitro, 3,4-dihydroxyphenylacetaldehyde (DOPAL) and the other two metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC) and 3,4-dihydroxyphenylethanol (DOPET), share the property to inhibit the growth of mature amyloid fibrils of α-synuclein. Although this effect occurs with the formation of differently toxic products, the molecular basis of this inhibition is still unclear. Here, we provide information on the effect of DOPAC on the aggregation properties of α-synuclein and its ability to interact with membranes. DOPAC inhibits α-synuclein aggregation, stabilizing monomer and inducing the formation of dimers and trimers. DOPAC-induced oligomers did not undergo conformational transition in the presence of membranes, and penetrated the cell, where they triggered autophagic processes. Cellular assays showed that DOPAC reduced cytotoxicity and ROS production induced by α-synuclein aggregates. Our findings show that the early radicals resulting from DOPAC autoxidation produced covalent modifications of the protein, which were not by themselves a primary cause of either fibrillation or membrane binding inhibition. These findings are discussed in the light of the potential mechanism of DOPAC protection against the toxicity of α-synuclein aggregates to better understand protein and catecholamine biology and to eventually suggest a scaffold that can help in the design of candidate molecules able to interfere in α-synuclein aggregation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Doença de Parkinson/genética , Agregação Patológica de Proteínas/genética , alfa-Sinucleína/genética , Ácido 3,4-Di-Hidroxifenilacético/análogos & derivados , Ácido 3,4-Di-Hidroxifenilacético/farmacologia , Amiloide/efeitos dos fármacos , Amiloide/genética , Dopamina/genética , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/farmacologia , Agregação Patológica de Proteínas/tratamento farmacológico , Multimerização Proteica/genética , alfa-Sinucleína/antagonistas & inibidores
5.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204581

RESUMO

Parkinson's disease (PD) is considered the most common disorder of synucleinopathy, which is characterised by intracellular inclusions of aggregated and misfolded α-synuclein (α-syn) protein in various brain regions, and the loss of dopaminergic neurons. During the early prodromal phase of PD, synaptic alterations happen before cell death, which is linked to the synaptic accumulation of toxic α-syn specifically in the presynaptic terminals, affecting neurotransmitter release. The oligomers and protofibrils of α-syn are the most toxic species, and their overexpression impairs the distribution and activation of synaptic proteins, such as the SNARE complex, preventing neurotransmitter exocytosis and neuronal synaptic communication. In the last few years, the role of the immune system in PD has been increasingly considered. Microglial and astrocyte activation, the gene expression of proinflammatory factors, and the infiltration of immune cells from the periphery to the central nervous system (CNS) represent the main features of the inflammatory response. One of the actors of these processes is α-syn accumulation. In light of this, here, we provide a systematic review of PD-related α-syn and inflammation inter-players.


Assuntos
Suscetibilidade a Doenças , Doença de Parkinson/metabolismo , Sinapses/metabolismo , alfa-Sinucleína/metabolismo , Imunidade Adaptativa , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Biomarcadores , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Humanos , Imunidade Inata , Microglia/imunologia , Microglia/metabolismo , Microglia/patologia , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Sinapses/imunologia , alfa-Sinucleína/genética
6.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209365

RESUMO

Mesenchymal stem cells (MSC) are potentially a good material for transplantation in many diseases, including neurodegenerative diseases. The main problem with using them is the low percentage of surviving cells after the transplant procedure and the naturally poor ability of MSC to spontaneously differentiate into certain types of cells, which results in their poor integration with the host cells. The aim and the novelty of this work consists in the synergistic overexpression of two genes, BCL2 and BDNF, using lentiviral vectors. According to our hypothesis, the overexpression of the BCL2 gene is aimed at increasing the resistance of cells to stressors and toxic factors. In turn, the overexpression of the BDNF gene is suspected to direct the MSC into the neural differentiation pathway. As a result, it was shown that the overexpression of both genes and the overproduction of proteins is permanent and persists for at least 60 days. The synergistically transduced MSC were significantly more resistant to the action of staurosporine; 12 days after transduction, the synergistically transduced MSC had a six-times greater survival rate. The overexpression of the Bcl-2 and BDNF proteins was sufficient to stimulate a significant overexpression of the CHAT gene, and under specific conditions, the TH, TPH1, and SYP genes were also overexpressed. Modified MSC are able to differentiate into cholinergic and dopaminergic neurons, and the release of acetylcholine and dopamine may indicate their functionality.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/biossíntese , Diferenciação Celular , Neurônios Dopaminérgicos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Neurônios Dopaminérgicos/citologia , Humanos , Lentivirus , Células-Tronco Mesenquimais/citologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transdução Genética
7.
Nat Commun ; 12(1): 4251, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253733

RESUMO

Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare genetic disorder characterized by deficient synthesis of dopamine and serotonin. It presents in early infancy, and causes severe developmental disability and lifelong motor, behavioral, and autonomic symptoms including oculogyric crises (OGC), sleep disorder, and mood disturbance. We investigated the safety and efficacy of delivery of a viral vector expressing AADC (AAV2-hAADC) to the midbrain in children with AADC deficiency (ClinicalTrials.gov Identifier NCT02852213). Seven (7) children, aged 4-9 years underwent convection-enhanced delivery (CED) of AAV2-hAADC to the bilateral substantia nigra (SN) and ventral tegmental area (VTA) (total infusion volume: 80 µL per hemisphere) in 2 dose cohorts: 1.3 × 1011 vg (n = 3), and 4.2 × 1011 vg (n = 4). Primary aims were to demonstrate the safety of the procedure and document biomarker evidence of restoration of brain AADC activity. Secondary aims were to assess clinical improvement in symptoms and motor function. Direct bilateral infusion of AAV2-hAADC was safe, well-tolerated and achieved target coverage of 98% and 70% of the SN and VTA, respectively. Dopamine metabolism was increased in all subjects and FDOPA uptake was enhanced within the midbrain and the striatum. OGC resolved completely in 6 of 7 subjects by Month 3 post-surgery. Twelve (12) months after surgery, 6/7 subjects gained normal head control and 4/7 could sit independently. At 18 months, 2 subjects could walk with 2-hand support. Both the primary and secondary endpoints of the study were met. Midbrain gene delivery in children with AADC deficiency is feasible and safe, and leads to clinical improvements in symptoms and motor function.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Erros Inatos do Metabolismo dos Aminoácidos/terapia , Descarboxilases de Aminoácido-L-Aromático/deficiência , Dependovirus/genética , Neurônios Dopaminérgicos/metabolismo , Técnicas de Transferência de Genes , Terapia Genética , Imageamento por Ressonância Magnética , Mesencéfalo/patologia , Erros Inatos do Metabolismo dos Aminoácidos/líquido cefalorraquidiano , Erros Inatos do Metabolismo dos Aminoácidos/fisiopatologia , Descarboxilases de Aminoácido-L-Aromático/líquido cefalorraquidiano , Descarboxilases de Aminoácido-L-Aromático/genética , Criança , Pré-Escolar , Discinesias/fisiopatologia , Feminino , Terapia Genética/efeitos adversos , Humanos , Masculino , Metaboloma , Atividade Motora , Neurotransmissores/líquido cefalorraquidiano , Neurotransmissores/metabolismo , Fatores de Tempo
8.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299000

RESUMO

Parkinson's disease (PD) is the most common movement disorder, characterized by progressive degeneration of the nigrostriatal pathway, which consists of dopaminergic cell bodies in substantia nigra and their neuronal projections to the striatum. Moreover, PD is associated with an array of non-motor symptoms such as olfactory dysfunction, gastrointestinal dysfunction, impaired regulation of the sleep-wake cycle, anxiety, depression, and cognitive impairment. Inflammation and concomitant oxidative stress are crucial in the pathogenesis of PD. Thus, this study aimed to model PD via intrastriatal injection of the inflammagen lipopolysaccharide (LPS)to investigate if the lesion causes olfactory and motor impairments, inflammation, oxidative stress, and alteration in synaptic proteins in the olfactory bulb, striatum, and colon. Ten µg of LPS was injected unilaterally into the striatum of 27 male C57BL/6 mice, and behavioural assessment was conducted at 4 and 8 weeks post-treatment, followed by tissue collection. Intrastriatal LPS induced motor impairment in C57BL/6 mice at 8 weeks post-treatment evidenced by reduced latency time in the rotarod test. LPS also induced inflammation in the striatum characterized by increased expression of microglial marker Iba-1 and astrocytic marker GFAP, with degeneration of dopaminergic neuronal fibres (reduced tyrosine hydroxylase immunoreactivity), and reduction of synaptic proteins and DJ-1 protein. Additionally, intrastriatal LPS induced inflammation, oxidative stress and alterations in synaptic proteins within the olfactory bulb, although this did not induce a significant impairment in olfactory function. Intrastriatal LPS induced mild inflammatory changes in the distal colon, accompanied by increased protein expression of 3-nitrotyrosine-modified proteins. This model recapitulated the major features of PD such as motor impairment and degeneration of dopaminergic neuronal fibres in the striatum, as well as some pathological changes in the olfactory bulb and colon; thus, this model could be suitable for understanding clinical PD and testing neuroprotective strategies.


Assuntos
Astrócitos/metabolismo , Colo/metabolismo , Corpo Estriado/metabolismo , Neurônios Dopaminérgicos/metabolismo , Lipopolissacarídeos/metabolismo , Bulbo Olfatório/metabolismo , Doença de Parkinson/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Escala de Avaliação Comportamental , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Colo/patologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Inflamação/metabolismo , Inflamação/patologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Microglia/patologia , Bulbo Olfatório/efeitos dos fármacos , Bulbo Olfatório/patologia , Estresse Oxidativo/efeitos dos fármacos , Doença de Parkinson/patologia , Doença de Parkinson/psicologia , Proteína Desglicase DJ-1/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Substância Negra/metabolismo , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo , alfa-Sinucleína/metabolismo
9.
Methods Mol Biol ; 2352: 97-115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34324182

RESUMO

Since the first demonstration of direct dopaminergic neuronal reprogramming, over a dozen methods have been developed to generate induced dopaminergic neurons from various sources of cells. Here, we first present an overview of the different methods to generate induced neurons of a generic type and of different subtypes, with a particular focus on induced dopaminergic neurons generated from human fibroblasts. We then describe a protocol to generate induced dopaminergic neurons from commercially available human fetal lung fibroblasts. These cells could serve for various biomedical application, including regenerative medicine for conditions such as Parkinson's disease.


Assuntos
Transdiferenciação Celular , Técnicas de Reprogramação Celular , Reprogramação Celular , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Diferenciação Celular/genética , Linhagem Celular , Células Cultivadas , Expressão Gênica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Lentivirus/genética , Fatores de Transcrição/genética
10.
Genes (Basel) ; 12(6)2021 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205689

RESUMO

Accumulation of α-Synuclein (αSyn) in nigral dopaminergic neurons is commonly seen in patients with Parkinson's disease (PD). We recently reported that transduction of intracellular single-chain intrabody targeting the 53-87 amino acid residues of human αSyn by recombinant adeno associated viral vector (AAV-NAC32) downregulated αSyn protein in SH-SY5Y cells and rat brain. This study characterizes the behavioral phenotype and dopaminergic protection in animals receiving AAV-NAC32. Our results show that adult DAT-Cre rats selectively overexpress αSyn in nigra dopaminergic neurons after local administration of AAV-DIO-αSyn. These animals develop PD-like phenotype, including bradykinesia and loss of tyrosine hydroxylase (TH) immunoreactivity in substantia nigra pars compacta dorsal tier (SNcd). An injection of AAV-NAC32 to nigra produces a selective antibody against αSyn and normalizes the behavior. AAV-NAC32 significantly increases TH, while reduces αSyn immunoreactivity in SNcd. Altogether, our data suggest that an AAV-mediated gene transfer of NAC32 antibody effectively antagonizes αSyn-mediated dopaminergic degeneration in nigra, which may be a promising therapeutic candidate for synucleinopathy or PD.


Assuntos
Anticorpos/uso terapêutico , Imunoterapia/métodos , Locomoção , Doença de Parkinson/terapia , alfa-Sinucleína/imunologia , Animais , Anticorpos/imunologia , Células CHO , Cricetinae , Cricetulus , Dependovirus/genética , Neurônios Dopaminérgicos/metabolismo , Vetores Genéticos/genética , Masculino , Doença de Parkinson/genética , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Ratos , Ratos Long-Evans , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , alfa-Sinucleína/química , alfa-Sinucleína/genética
11.
Cell Death Dis ; 12(7): 674, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226513

RESUMO

Parkinson's disease is a common neurodegenerative disease. Cell transplantation is a promising therapeutic option for improving the survival and function of dopaminergic neurons, but the mechanisms underlying the interaction between the transplanted cells and the recipient neurons remain to be studied. In this study, we investigated the effects of skin precursor cell-derived Schwann cells (SKP-SCs) directly cocultured with 6-OHDA-injured dopaminergic neurons in vitro and of SKP-SCs transplanted into the brains of 6-OHDA-induced PD mice in vivo. In vitro and in vivo studies revealed that SKP-SCs could reduce the damage to dopaminergic neurons by enhancing self-autophagy and modulating neuronal autophagy. Thus, the present study provides the first evidence that cell transplantation mitigates 6-OHDA-induced damage to dopaminergic neurons by enhancing self-autophagy, suggesting that earlier transplantation of Schwann cells might help alleviate the loss of dopaminergic neurons.


Assuntos
Autofagia , Encéfalo/patologia , Neurônios Dopaminérgicos/patologia , Transtornos Parkinsonianos/prevenção & controle , Células de Schwann/transplante , Transplante de Células-Tronco , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Encéfalo/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Oxidopamina , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Fenótipo , Ratos Sprague-Dawley , Células de Schwann/metabolismo , Pele/citologia , Serina-Treonina Quinases TOR/metabolismo
12.
Cell Prolif ; 54(8): e13094, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34312932

RESUMO

OBJECTIVES: Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive and selective degeneration of dopaminergic neurons. Microglial activation and neuroinflammation are associated with the pathogenesis of PD. However, the relationship between microglial activation and PD pathology remains to be explored. MATERIALS AND METHODS: An acute regimen of MPTP was administered to adult C57BL/6J mice with normal, much reduced or repopulated microglial population. Damages of the dopaminergic system were comprehensively assessed. Inflammation-related factors were assessed by quantitative PCR and Multiplex immunoassay. Behavioural tests were carried out to evaluate the motor deficits in MPTP-challenged mice. RESULTS: The receptor for colony-stimulating factor 1 inhibitor PLX3397 could effectively deplete microglia in the nigrostriatal pathway of mice via feeding a PLX3397-formulated diet for 21 days. Microglial depletion downregulated both pro-inflammatory and anti-inflammatory molecule expression at baseline and after MPTP administration. At 1d post-MPTP injection, dopaminergic neurons showed a significant reduction in PLX3397-fed mice, but not in control diet (CD)-fed mice. However, partial microglial depletion in mice exerted little effect on MPTP-induced dopaminergic injuries compared with CD mice at later time points. Interestingly, microglial repopulation brought about apparent resistance to MPTP intoxication. CONCLUSIONS: Microglia can inhibit PD development at a very early stage; partial microglial depletion has little effect in terms of the whole process of the disease; and microglial replenishment elicits neuroprotection in PD mice.


Assuntos
Intoxicação por MPTP/patologia , Microglia/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/administração & dosagem , Aminopiridinas/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Mediadores da Inflamação/metabolismo , Intoxicação por MPTP/metabolismo , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Pirróis/farmacologia , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
13.
Int J Mol Sci ; 22(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299176

RESUMO

The benefits of a ketogenic diet in childhood epilepsy steered up hope for neuroprotective effects of hyperketonemia in Parkinson's disease (PD). There are multiple theoretical reasons but very little actual experimental proof or clinical trials. We examined the long-term effects of the ketogenic diet in an animal model of early PD. A progressive, selective dopaminergic medium size lesion was induced by 6-OHDA injection into the medial forebrain bundle. Animals were kept on the stringent ketogenic diet (1% carbohydrates, 8% protein, 70% fat) for 3 weeks prior and 4 weeks after the brain operation. Locomotor activity, neuron count, dopaminergic terminal density, dopamine level, and turnover were analyzed at three time-points post-lesion, up to 4 weeks after the operation. Energy metabolism parameters (glycogen, mitochondrial complex I and IV, lactate, beta-hydroxybutyrate, glucose) were analyzed in the brain and liver or plasma. Protein expression of enzymes essential for gluconeogenesis (PEPCK, G6PC) and glucose utilization (GCK) was analyzed in the liver. Despite long-term hyperketonemia pre- and post-lesion, the ketogenic diet did not protect against 6-OHDA-induced dopaminergic neuron lesions. The ketogenic diet only tended to improve locomotor activity and normalize DA turnover in the striatum. Rats fed 7 weeks in total with a restrictive ketogenic diet maintained normoglycemia, and neither gluconeogenesis nor glycogenolysis in the liver was responsible for this effect. Therefore, potentially, the ketogenic diet could be therapeutically helpful to support the late compensatory mechanisms active via glial cells but does not necessarily act against the oxidative stress-induced parkinsonian neurodegeneration itself. A word of caution is required as the stringent ketogenic diet itself also carries the risk of unwanted side effects, so it is important to study the long-term effects of such treatments. More detailed metabolic long-term studies using unified diet parameters are required, and human vs. animal differences should be taken under consideration.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Encéfalo/patologia , Dieta Cetogênica/efeitos adversos , Neurônios Dopaminérgicos/patologia , Fígado/patologia , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/patologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Ratos , Ratos Wistar
14.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206041

RESUMO

Parkinson's disease (PD) is characterized mainly by the loss of dopaminergic neurons in the substantia nigra (SN) mediated via oxidative stress. Although glutaredoxin-1 (GLRX1) is known as one of the antioxidants involved in cell survival, the effects of GLRX1 on PD are still unclear. In this study, we investigated whether cell-permeable PEP-1-GLRX1 inhibits dopaminergic neuronal cell death induced by 1-methyl-4-phenylpyridinium (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We showed that PEP-1-GLRX1 protects cell death and DNA damage in MPP+-exposed SH-SY5Y cells via the inhibition of MAPK, Akt, and NF-κB activation and the regulation of apoptosis-related protein expression. Furthermore, we found that PEP-1-GLRX1 was delivered to the SN via the blood-brain barrier (BBB) and reduced the loss of dopaminergic neurons in the MPTP-induced PD model. These results indicate that PEP-1-GLRX1 markedly inhibited the loss of dopaminergic neurons in MPP+- and MPTP-induced cytotoxicity, suggesting that this fusion protein may represent a novel therapeutic agent against PD.


Assuntos
Cisteamina/análogos & derivados , Neurônios Dopaminérgicos/citologia , Glutarredoxinas/administração & dosagem , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Peptídeos/química , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , 1-Metil-4-fenilpiridínio/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Cisteamina/química , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glutarredoxinas/química , Glutarredoxinas/farmacologia , Humanos , Masculino , Camundongos , Doença de Parkinson/etiologia , Doença de Parkinson/metabolismo , Substância Negra/química
15.
Int J Mol Sci ; 22(14)2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34299248

RESUMO

Parkinson's disease (PD) is a complex and progressive neurodegenerative disorder with a prevalence of approximately 0.5-1% among those aged 65-70 years. Although most of its clinical manifestations are due to a loss of dopaminergic neurons, the PD etiology is largely unknown. PD is caused by a combination of genetic and environmental factors, and the exact interplay between genes and the environment is still debated. Several biological processes have been implicated in PD, including mitochondrial or lysosomal dysfunctions, alteration in protein clearance, and neuroinflammation, but a common molecular mechanism connecting the different cellular alterations remains incompletely understood. Accumulating evidence underlines a significant role of lipids in the pathological pathways leading to PD. Beside the well-described lipid alteration in idiopathic PD, this review summarizes the several lipid alterations observed in experimental models expressing PD-related genes and suggests a possible scenario in relationship to the molecular mechanisms of neuronal toxicity. PD could be considered a lipid-induced proteinopathy, where alteration in lipid composition or metabolism could induce protein alteration-for instance, alpha-synuclein accumulation-and finally neuronal death.


Assuntos
Metabolismo dos Lipídeos/genética , Lipídeos/fisiologia , Doença de Parkinson/genética , Neurônios Dopaminérgicos/metabolismo , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Fosfolipases A2 do Grupo VI/genética , Fosfolipases A2 do Grupo VI/metabolismo , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Lisossomos/metabolismo , Mitocôndrias/metabolismo , Degeneração Neural/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
16.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299375

RESUMO

A real-life environment during pregnancy involves multiple and simultaneous exposures to toxic chemicals. Perinatal exposures to toxic chemicals have been reported to exert an inhibitory effect on mouse neural development and behaviors. However, the effect of combined exposures of organophosphate and nicotine has not been previously reported. In this study, we investigated whether a combined exposure of diazinon and nicotine can have a synergistic effect. The effects of the combined chemical exposure on cell viability and neuronal differentiation were examined using mouse Sox1-GFP cells. Additionally, mice were maternally administered 0.18 mg/kg diazinon, a no adverse effect level (NOAEL) dose, combined with 0.4, 1, and 2 mg/kg nicotine. Mice offspring underwent behavior tests to assess locomotor, depressive, cognitive, and social behaviors. Morphological change in the brain was investigated with immunolocalization. We revealed that the combined exposure to diazinon and nicotine can have a synergistic adverse effect in vitro. In addition, the chemical-treated mouse offspring showed abnormalities in motor learning, compulsive-like behaviors, spatial learning, and social interaction patterns. Moreover, 0.18 mg/kg diazinon and 2 mg/kg nicotine co-exposure resulted in an increase in tyrosine hydroxylase (TH)-positive dopaminergic neurons. Thus, the findings suggest that perinatal co-exposure to nicotine and diazinon can result in abnormal neurodevelopment and behavior, even at low-level administration.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Diazinon/efeitos adversos , Nicotina/efeitos adversos , Animais , Células Cultivadas , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Feminino , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Comportamento Social , Aprendizagem Espacial/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
17.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201785

RESUMO

Alpha-synuclein (α-syn) and leucine-rich repeat kinase 2 (LRRK2) play crucial roles in Parkinson's disease (PD). They may functionally interact to induce the degeneration of dopaminergic (DA) neurons via mechanisms that are not yet fully understood. We previously showed that the C-terminal portion of LRRK2 (ΔLRRK2) with the G2019S mutation (ΔLRRK2G2019S) was sufficient to induce neurodegeneration of DA neurons in vivo, suggesting that mutated LRRK2 induces neurotoxicity through mechanisms that are (i) independent of the N-terminal domains and (ii) "cell-autonomous". Here, we explored whether ΔLRRK2G2019S could modify α-syn toxicity through these two mechanisms. We used a co-transduction approach in rats with AAV vectors encoding ΔLRRK2G2019S or its "dead" kinase form, ΔLRRK2DK, and human α-syn with the A53T mutation (AAV-α-synA53T). Behavioral and histological evaluations were performed at 6- and 15-weeks post-injection. Results showed that neither form of ΔLRRK2 alone induced the degeneration of neurons at these post-injection time points. By contrast, injection of AAV-α-synA53T alone resulted in motor signs and degeneration of DA neurons. Co-injection of AAV-α-synA53T with AAV-ΔLRRK2G2019S induced DA neuron degeneration that was significantly higher than that induced by AAV-α-synA53T alone or with AAV-ΔLRRK2DK. Thus, mutated α-syn neurotoxicity can be enhanced by the C-terminal domain of LRRK2G2019 alone, through cell-autonomous mechanisms.


Assuntos
Modelos Animais de Doenças , Neurônios Dopaminérgicos/patologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Proteínas Mutantes/metabolismo , Mutação , alfa-Sinucleína/metabolismo , Animais , Neurônios Dopaminérgicos/metabolismo , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Proteínas Mutantes/genética , Domínios Proteicos , Ratos , alfa-Sinucleína/genética
18.
Nat Commun ; 12(1): 4409, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34285209

RESUMO

Appetitive locomotion is essential for animals to approach rewards, such as food and prey. The neuronal circuitry controlling appetitive locomotion is unclear. In a goal-directed behavior-predatory hunting, we show an excitatory brain circuit from the superior colliculus (SC) to the substantia nigra pars compacta (SNc) to enhance appetitive locomotion in mice. This tectonigral pathway transmits locomotion-speed signals to dopamine neurons and triggers dopamine release in the dorsal striatum. Synaptic inactivation of this pathway impairs appetitive locomotion but not defensive locomotion. Conversely, activation of this pathway increases the speed and frequency of approach during predatory hunting, an effect that depends on the activities of SNc dopamine neurons. Together, these data reveal that the SC regulates locomotion-speed signals to SNc dopamine neurons to enhance appetitive locomotion in mice.


Assuntos
Comportamento Apetitivo/fisiologia , Locomoção/fisiologia , Parte Compacta da Substância Negra/fisiologia , Comportamento Predatório/fisiologia , Colículos Superiores/fisiologia , Animais , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Modelos Animais , Vias Neurais/fisiologia , Parte Compacta da Substância Negra/citologia , Técnicas Estereotáxicas , Colículos Superiores/citologia , Transmissão Sináptica/fisiologia
19.
Nat Commun ; 12(1): 3495, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108486

RESUMO

Lysosomal storage disorders characterized by altered metabolism of heparan sulfate, including Mucopolysaccharidosis (MPS) III and MPS-II, exhibit lysosomal dysfunctions leading to neurodegeneration and dementia in children. In lysosomal storage disorders, dementia is preceded by severe and therapy-resistant autistic-like symptoms of unknown cause. Using mouse and cellular models of MPS-IIIA, we discovered that autistic-like behaviours are due to increased proliferation of mesencephalic dopamine neurons originating during embryogenesis, which is not due to lysosomal dysfunction, but to altered HS function. Hyperdopaminergia and autistic-like behaviours are corrected by the dopamine D1-like receptor antagonist SCH-23390, providing a potential alternative strategy to the D2-like antagonist haloperidol that has only minimal therapeutic effects in MPS-IIIA. These findings identify embryonic dopaminergic neurodevelopmental defects due to altered function of HS leading to autistic-like behaviours in MPS-II and MPS-IIIA and support evidence showing that altered HS-related gene function is causative of autism.


Assuntos
Transtorno do Espectro Autista/metabolismo , Dopamina/metabolismo , Heparitina Sulfato/metabolismo , Doenças por Armazenamento dos Lisossomos/metabolismo , Animais , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/patologia , Benzazepinas/uso terapêutico , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Antagonistas de Dopamina/uso terapêutico , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Heparitina Sulfato/farmacologia , Doenças por Armazenamento dos Lisossomos/tratamento farmacológico , Doenças por Armazenamento dos Lisossomos/patologia , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/embriologia , Mesencéfalo/patologia , Camundongos , Mucopolissacaridose III/tratamento farmacológico , Mucopolissacaridose III/metabolismo , Mucopolissacaridose III/patologia , Receptores de Dopamina D1/antagonistas & inibidores , Receptores de Dopamina D1/metabolismo
20.
Development ; 148(12)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34121117

RESUMO

The Ciona larva has served as a unique model for understanding the development of dopaminergic cells at single-cell resolution owing to the exceptionally small number of neurons in its brain and its fixed cell lineage during embryogenesis. A recent study suggested that the transcription factors Fer2 and Meis directly regulate the dopamine synthesis genes in Ciona, but the dopaminergic cell lineage and the gene regulatory networks that control the development of dopaminergic cells have not been fully elucidated. Here, we reveal that the dopaminergic cells in Ciona are derived from a bilateral pair of cells called a9.37 cells at the center of the neural plate. The a9.37 cells divide along the anterior-posterior axis, and all of the descendants of the posterior daughter cells differentiate into the dopaminergic cells. We show that the MAPK pathway and the transcription factor Otx are required for the expression of Fer2 in the dopaminergic cell lineage. Our findings establish the cellular and molecular framework for fully understanding the commitment to dopaminergic cells in the simple chordate brain.


Assuntos
Encéfalo/citologia , Encéfalo/metabolismo , Diferenciação Celular/genética , Ciona/genética , Neurônios Dopaminérgicos/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Fatores de Transcrição Otx/genética , Animais , Biomarcadores , Linhagem da Célula/genética , Ciona/citologia , Neurônios Dopaminérgicos/citologia , Imunofluorescência , Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Placa Neural/citologia , Placa Neural/metabolismo , Fatores de Transcrição Otx/metabolismo , Transdução de Sinais
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