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1.
Biomolecules ; 14(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38672506

RESUMO

Parkinson's disease (PD) is a neurodegenerative movement disorder associated with a loss of dopamine neurons in the substantia nigra. The diagnosis of PD is sensitive since it shows clinical features that are common with other neurodegenerative diseases. In addition, most symptoms arise at the late stage of the disease, where most dopaminergic neurons are already damaged. Several studies reported that oxidative stress is a key modulator in the development of PD. This condition occurs due to excess reactive oxygen species (ROS) production in the cellular system and the incapability of antioxidants to neutralize it. In this study, we focused on the pathology of PD by measuring serum xanthine oxidase (XO) activity, which is an enzyme that generates ROS. Interestingly, the serum XO activity of patients with PD was markedly upregulated compared to patients with other neurological diseases (ONDs) as a control. Moreover, serum XO activity in patients with PD showed a significant correlation with the disease severity based on the Hoehn and Yahr (HY) stages. The investigation of antioxidant status also revealed that serum uric acid levels were significantly lower in the severe group (HY ≥ 3) than in the ONDs group. Together, these results suggest that XO activity may contribute to the development of PD and might potentially be a biomarker for determining disease severity in patients with PD.


Assuntos
Antioxidantes , Doença de Parkinson , Ácido Úrico , Xantina Oxidase , Humanos , Doença de Parkinson/sangue , Doença de Parkinson/metabolismo , Xantina Oxidase/sangue , Xantina Oxidase/metabolismo , Masculino , Feminino , Idoso , Antioxidantes/metabolismo , Pessoa de Meia-Idade , Ácido Úrico/sangue , Biomarcadores/sangue , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/sangue
2.
Intern Med ; 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38171860

RESUMO

An 83-year-old man with hepatocellular carcinoma developed muscle weakness, ptosis, and dyspnea 3 weeks after receiving atezolizumab. Soon after, mechanical ventilation was initiated, which was followed by marked blood pressure spikes. The levels of creatine kinase and troponin-I were significantly elevated, and acetylcholine receptor antibodies were positive. The patient was diagnosed with immune checkpoint inhibitor (ICI)-induced myositis, myasthenia gravis (MG), myocarditis, and suspected autoimmune autonomic ganglionopathy (AAG). After immunotherapy, the serum markers and blood pressure normalized, and he was weaned from the ventilator after five months. To our knowledge, this is the first reported case of AAG secondary to ICI-induced myositis, MG, and myocarditis.

3.
Intern Med ; 63(7): 1009-1014, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37612090

RESUMO

A 68-year-old man with small-cell lung cancer developed anti-collapsin response-mediator protein (CRMP)-5 antibody-related paraneoplastic neurological syndrome (PNS) presenting with ataxia and chorea during treatment with durvalumab. As a result of steroid therapy, anti-CRMP-5 antibodies became negative, hyperintense lesions on brain magnetic resonance imaging disappeared, and neurological symptoms improved. After resuming durvalumab, he became unable to walk due to neurological adverse events (nAEs). There have been no reported cases manifesting PNSs and nAEs as a result of the same immune checkpoint inhibitors (ICIs) administered at different times. Resuming ICIs in patients diagnosed with PNSs should be performed with prudence.


Assuntos
Neoplasias Pulmonares , Síndromes Paraneoplásicas , Carcinoma de Pequenas Células do Pulmão , Masculino , Humanos , Idoso , Neoplasias Pulmonares/tratamento farmacológico , Síndromes Paraneoplásicas/diagnóstico , Anticorpos Monoclonais/efeitos adversos , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico
4.
Proc Natl Acad Sci U S A ; 121(1): e2312306120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38147546

RESUMO

The neuron-to-neuron propagation of misfolded α-synuclein (αSyn) aggregates is thought to be key to the pathogenesis of synucleinopathies. Recent studies have shown that extracellular αSyn aggregates taken up by the endosomal-lysosomal system can rupture the lysosomal vesicular membrane; however, it remains unclear whether lysosomal rupture leads to the transmission of αSyn aggregation. Here, we applied cell-based αSyn propagation models to show that ruptured lysosomes are the pathway through which exogenous αSyn aggregates transmit aggregation, and furthermore, this process was prevented by lysophagy, i.e., selective autophagy of damaged lysosomes. αSyn aggregates accumulated predominantly in lysosomes, causing their rupture, and seeded the aggregation of endogenous αSyn, initially around damaged lysosomes. Exogenous αSyn aggregates induced the accumulation of LC3 on lysosomes. This LC3 accumulation was not observed in cells in which a key regulator of autophagy, RB1CC1/FIP200, was knocked out and was confirmed as lysophagy by transmission electron microscopy. Importantly, RB1CC1/FIP200-deficient cells treated with αSyn aggregates had increased numbers of ruptured lysosomes and enhanced propagation of αSyn aggregation. Furthermore, various types of lysosomal damage induced using lysosomotropic reagents, depletion of lysosomal enzymes, or more toxic species of αSyn fibrils also exacerbated the propagation of αSyn aggregation, and impaired lysophagy and lysosomal membrane damage synergistically enhanced propagation. These results indicate that lysophagy prevents exogenous αSyn aggregates from escaping the endosomal-lysosomal system and transmitting aggregation to endogenous cytosolic αSyn via ruptured lysosomal vesicles. Our findings suggest that the progression and severity of synucleinopathies are associated with damage to lysosomal membranes and impaired lysophagy.


Assuntos
Doença de Parkinson , Sinucleinopatias , Humanos , alfa-Sinucleína/metabolismo , Macroautofagia , Sinucleinopatias/metabolismo , Doença de Parkinson/metabolismo , Lisossomos/metabolismo
5.
Stem Cell Res ; 69: 103122, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209469

RESUMO

Infantile neuroaxonal dystrophy (INAD) is a rare neurodegenerative disease caused mainly by homozygous or compound heterozygous mutations in the PLA2G6 gene. We generated a human induced pluripotent stem cell (hiPSC) line (ONHi001-A) using fibroblasts derived from a patient with INAD. The patient exhibited c.517C > T (p.Q173X) and c.1634A > G (p.K545R) compound heterozygous mutations in the PLA2G6 gene. This hiPSC line may be useful for studying the pathogenic mechanism underlying INAD.


Assuntos
Células-Tronco Pluripotentes Induzidas , Distrofias Neuroaxonais , Doenças Neurodegenerativas , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Doenças Neurodegenerativas/genética , Mutação/genética , Homozigoto , Distrofias Neuroaxonais/genética , Distrofias Neuroaxonais/patologia , Fosfolipases A2 do Grupo VI/genética
6.
Acta Neuropathol ; 145(5): 573-595, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939875

RESUMO

Lipid interaction with α-synuclein (αSyn) has been long implicated in the pathogenesis of Parkinson's disease (PD). However, it has not been fully determined which lipids are involved in the initiation of αSyn aggregation in PD. Here exploiting genetic understanding associating the loss-of-function mutation in Synaptojanin 1 (SYNJ1), a phosphoinositide phosphatase, with familial PD and analysis of postmortem PD brains, we identified a novel lipid molecule involved in the toxic conversion of αSyn and its relation to PD. We first established a SYNJ1 knockout cell model and found SYNJ1 depletion increases the accumulation of pathological αSyn. Lipidomic analysis revealed SYNJ1 depletion elevates the level of its substrate phosphatidylinositol-3,4,5-trisphosphate (PIP3). We then employed Caenorhabditis elegans model to examine the effect of SYNJ1 defect on the neurotoxicity of αSyn. Mutations in SYNJ1 accelerated the accumulation of αSyn aggregation and induced locomotory defects in the nematodes. These results indicate that functional loss of SYNJ1 promotes the pathological aggregation of αSyn via the dysregulation of its substrate PIP3, leading to the aggravation of αSyn-mediated neurodegeneration. Treatment of cultured cell line and primary neurons with PIP3 itself or with PIP3 phosphatase inhibitor resulted in intracellular formation of αSyn inclusions. Indeed, in vitro protein-lipid overlay assay validated that phosphoinositides, especially PIP3, strongly interact with αSyn. Furthermore, the aggregation assay revealed that PIP3 not only accelerates the fibrillation of αSyn, but also induces the formation of fibrils sharing conformational and biochemical characteristics similar to the fibrils amplified from the brains of PD patients. Notably, the immunohistochemical and lipidomic analyses on postmortem brain of patients with sporadic PD showed increased PIP3 level and its colocalization with αSyn. Taken together, PIP3 dysregulation promotes the pathological aggregation of αSyn and increases the risk of developing PD, and PIP3 represents a potent target for intervention in PD.


Assuntos
Doença de Parkinson , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Encéfalo/patologia , Lipídeos , Neurônios/patologia , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo
7.
Front Neurosci ; 16: 964928, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36117634

RESUMO

Background: Recently, the common marmoset (Callithrix jacchus) has attracted significant interest as a non-human primate stroke model. Functional impairment in non-human primate stroke models should be evaluated quantitatively and successively after stroke, but conventional observational assessments of behavior cannot fully fit this purpose. In this paper, we report a behavioral analysis using MarmoDetector, a three-dimensional motion analysis, in an ischemic stroke model using photosensitive dye, along with an observational behavioral assessment and imaging examination. Methods: Ischemic stroke was induced in the left hemisphere of three marmosets. Cerebral infarction was induced by intravenous injection of rose bengal and irradiation with green light. The following day, the success of the procedure was confirmed by magnetic resonance imaging (MRI). The distance traveled, speed, activity time, and jumps/climbs were observed for 28 days after stroke using MarmoDetector. We also assessed the marmosets' specific movements and postural abnormalities using conventional neurological scores. Results: Magnetic resonance imaging diffusion-weighted and T2-weighted images showed hyperintense signals, indicating cerebral infarction in all three marmosets. MarmoDetector data showed that the both indices immediately after stroke onset and gradually improved over weeks. Neurological scores were the worst immediately after stroke and did not recover to pre-infarction levels during the observation period (28 days). A significant correlation was observed between MarmoDetector data and conventional neurological scores. Conclusion: In this study, we showed that MarmoDetector can quantitatively evaluate behavioral changes in the acute to subacute phases stroke models. This technique can be practical for research on the pathophysiology of ischemic stroke and for the development of new therapeutic methods.

8.
Intern Med ; 61(23): 3589-3594, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35527021

RESUMO

Phosphoglycerate kinase (PGK) deficiency is an X-linked disorder characterized by a combination of hemolytic anemia, myopathy, and brain involvement. We herein report a Japanese man who had several episodes of rhabdomyolysis but was training strenuously to be a professional boxer. Mild hemolytic anemia was noted. The enzymatic activity of PGK was significantly reduced, and a novel missense mutation, p.S62N, was identified in the PGK1 gene. A literature review revealed only one case with a mixed hemolytic and myopathic phenotype like ours. This mild phenotype indicates the complex pathophysiology of PGK deficiency and suggests the benefits of dietary control and exercise.


Assuntos
Doenças Genéticas Ligadas ao Cromossomo X , Erros Inatos do Metabolismo , Humanos , Fosfoglicerato Quinase/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Erros Inatos do Metabolismo/complicações , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Fenótipo , Hemólise
9.
Eur J Neurol ; 29(5): 1410-1416, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35128793

RESUMO

BACKGROUND AND PURPOSE: The aim was to investigate the association between serum asymmetric dimethylarginine (ADMA) levels and the progression and prognosis of amyotrophic lateral sclerosis (ALS), and to compare cerebrospinal fluid (CSF) and serum ADMA levels with other biomarkers of ALS. METHODS: Serum ADMA levels of sporadic ALS patients (n = 68), disease control patients (n = 54) and healthy controls (n = 20) were measured using liquid chromatography tandem mass spectrometry. Correlations of the ADMA level and other markers (nitric oxide and neurofilament light chain levels) were analyzed. Changes in the ALS Functional Rating Scale Revised (ALSFRS-R) score from the onset of disease (ALSFRS-R pre-slope) was used to assess disease progression. Survival was evaluated using the Cox proportional hazards model and Kaplan-Meier analysis. RESULTS: The serum ADMA level was substantially higher in patients with ALS than in healthy controls and disease controls. Serum ADMA level correlated with CSF ADMA level (r = 0.591, p < 0.0001) and was independently associated with the ALSFRS-R pre-slope (r = 0.505, p < 0.0001). Patients with higher serum ADMA levels had less favorable prognoses. CSF ADMA level significantly correlated with CSF neurofilament light chain level (r = 0.456, p = 0.0002) but not with nitric oxide level (r = 0.194, p = 0.219). CONCLUSION: Serum ADMA level is an independent biomarker of ALS disease progression and prognosis and reflects the degree of motor neuron degeneration.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/diagnóstico , Arginina/análogos & derivados , Biomarcadores , Progressão da Doença , Humanos , Óxido Nítrico , Prognóstico
10.
Intern Med ; 61(17): 2661-2666, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35135916

RESUMO

Erdheim-Chester disease (ECD) is a rare, non-Langerhans cell histiocytosis characterized by the infiltration of foamy histiocytes into multiple organs. We herein report a case of ECD with central nervous system (CNS) involvement in a 63-year-old man who also presented a positive result for Toxoplasma gondii nested polymerase chain reaction testing of cerebrospinal fluid. Since anti-Toxoplasma treatment proved completely ineffective, we presumed latent infection of the CNS with T. gondii. This case suggests the difficulty of distinguishing ECD with CNS involvement from toxoplasmic encephalitis and the possibility of a relationship between the pathogeneses of ECD and infection with T. gondii.


Assuntos
Doença de Erdheim-Chester , Histiocitose de Células não Langerhans , Toxoplasmose , Sistema Nervoso Central , Doença de Erdheim-Chester/complicações , Doença de Erdheim-Chester/diagnóstico , Doença de Erdheim-Chester/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
11.
Mol Neurobiol ; 59(3): 1693-1705, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35015250

RESUMO

The pathological hallmark of the majority of amyotrophic lateral sclerosis (ALS) cases is the mislocalization and aggregation of TAR DNA-binding protein 43 (TDP-43), an RNA-binding protein. Several studies have attributed disease processes of ALS to abnormal RNA metabolism. However, dysregulated biogenesis of RNA, especially non-coding RNA (ncRNA), is poorly understood. To resolve it, RNA-Seq, biochemical, and immunohistochemical analyses were performed on the pyramidal tract of the medulla oblongata of sporadic ALS (sALS) and control postmortem brain samples. Here, we report perturbation of ncRNA biogenesis in PIWI-interacting RNA (piRNA) in several sALS brain samples associated with TDP-43 pathology. In addition, we confirmed the dysregulation of two PIWI homologs, PIWI-like-mediated gene silencing 1 (PIWIL1) and PIWIL4, which bind to piRNAs to regulate their expression. PIWIL1 was mislocalized and co-localized with TDP-43 in motor neurons of sporadic ALS lumbar cords. Our results imply that dysregulation of piRNA, PIWIL1, and PIWIL4 is linked to pathogenesis of ALS. Based on these results, piRNAs and PIWI proteins are potential diagnostic biomarkers and therapeutic targets of ALS.


Assuntos
Esclerose Lateral Amiotrófica , Esclerose Lateral Amiotrófica/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Biomarcadores/metabolismo , Humanos , Neurônios Motores/metabolismo , RNA Interferente Pequeno/metabolismo
12.
Sci Rep ; 12(1): 351, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013421

RESUMO

Parkinson's disease is a neurodegenerative disease characterized by the formation of neuronal inclusions of α-synuclein in patient brains. As the disease progresses, toxic α-synuclein aggregates transmit throughout the nervous system. No effective disease-modifying therapy has been established, and preventing α-synuclein aggregation is thought to be one of the most promising approaches to ameliorate the disease. In this study, we performed a two-step screening using the thioflavin T assay and a cell-based assay to identify α-synuclein aggregation inhibitors. The first screening, thioflavin T assay, allowed the identification of 30 molecules, among a total of 1262 FDA-approved small compounds, which showed inhibitory effects on α-synuclein fibrilization. In the second screening, a cell-based aggregation assay, seven out of these 30 candidates were found to prevent α-synuclein aggregation without causing substantial toxicity. Of the seven final candidates, tannic acid was the most promising compound. The robustness of our screening method was validated by a primary neuronal cell model and a Caenorhabditis elegans model, which demonstrated the effect of tannic acid against α-synuclein aggregation. In conclusion, our two-step screening system is a powerful method for the identification of α-synuclein aggregation inhibitors, and tannic acid is a promising candidate as a disease-modifying drug for Parkinson's disease.


Assuntos
Antiparkinsonianos/farmacologia , Ensaios de Triagem em Larga Escala , Neurônios/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Agregação Patológica de Proteínas , Taninos/farmacologia , alfa-Sinucleína/metabolismo , Animais , Animais Geneticamente Modificados , Antiparkinsonianos/toxicidade , Benzotiazóis/química , Bioensaio , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Modelos Animais de Doenças , Reposicionamento de Medicamentos , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Neurônios/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Agregados Proteicos , Espectrometria de Fluorescência , Taninos/toxicidade , alfa-Sinucleína/genética , alfa-Sinucleína/ultraestrutura
13.
Mol Brain ; 14(1): 149, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34629097

RESUMO

The generation of mature synaptic structures using neurons differentiated from human-induced pluripotent stem cells (hiPSC-neurons) is expected to be applied to physiological studies of synapses in human cells and to pathological studies of diseases that cause abnormal synaptic function. Although it has been reported that synapses themselves change from an immature to a mature state as neurons mature, there are few reports that clearly show when and how human stem cell-derived neurons change to mature synaptic structures. This study was designed to elucidate the synapse formation process of hiPSC-neurons. We propagated hiPSC-derived neural progenitor cells (hiPSC-NPCs) that expressed localized markers of the ventral hindbrain as neurospheres by dual SMAD inhibition and then differentiated them into hiPSC-neurons in vitro. After 49 days of in vitro differentiation, hiPSC-neurons significantly expressed pre- and postsynaptic markers at both the transcript and protein levels. However, the expression of postsynaptic markers was lower than in normal human or normal rat brain tissues, and immunostaining analysis showed that it was relatively modest and was lower than that of presynaptic markers and that its localization in synaptic structures was insufficient. Neurophysiological analysis using a microelectrode array also revealed that no synaptic activity was generated on hiPSC-neurons at 49 days of differentiation. Analysis of subtype markers by immunostaining revealed that most hiPSC-neurons expressed vesicular glutamate transporter 2 (VGLUT2). The presence or absence of NGF, which is required for the survival of cholinergic neurons, had no effect on their cell fractionation. These results suggest that during the synaptogenesis of hiPSC-neurons, the formation of presynaptic structures is not the only requirement for the formation of postsynaptic structures and that the mRNA expression of postsynaptic markers does not correlate with the formation of their mature structures. Technically, we also confirmed a certain level of robustness and reproducibility of our neuronal differentiation method in a multicenter setting, which will be helpful for future research. Synapse formation with mature postsynaptic structures will remain an interesting issue for stem cell-derived neurons, and the present method can be used to obtain early and stable quality neuronal cultures from hiPSC-NPCs.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Neurais/citologia , Neurogênese , Animais , Biomarcadores , Técnicas de Cultura de Células/métodos , Linhagem Celular , Hipocampo/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/análise , Células-Tronco Neurais/ultraestrutura , Neurônios/química , Neurônios/classificação , Neurônios/citologia , Neuropeptídeos/análise , Terminações Pré-Sinápticas/ultraestrutura , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Reprodutibilidade dos Testes , Sinapses/fisiologia , Proteína Vesicular 1 de Transporte de Glutamato/análise , Proteína Vesicular 2 de Transporte de Glutamato/análise
15.
Cell Death Dis ; 12(2): 181, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589594

RESUMO

Repulsive guidance molecule-a (RGMa), a glycosylphosphatidylinositol-anchored membrane protein, has diverse functions in axon guidance, cell patterning, and cell survival. Inhibition of RGMa attenuates pathological dysfunction in animal models of central nervous system (CNS) diseases including spinal cord injury, multiple sclerosis, and neuromyelitis optica. Here, we examined whether antibody-based inhibition of RGMa had therapeutic effects in a mouse model of Parkinson's disease (PD). We treated mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and found increased RGMa expression in the substantia nigra (SN). Intraventricular, as well as intravenous, administration of anti-RGMa antibodies reduced the loss of tyrosine hydroxylase (TH)-positive neurons and accumulation of Iba1-positive microglia/macrophages in the SN of MPTP-treated mice. Selective expression of RGMa in TH-positive neurons in the SN-induced neuronal loss/degeneration and inflammation, resulting in a progressive movement disorder. The pathogenic effects of RGMa overexpression were attenuated by treatment with minocycline, which inhibits microglia and macrophage activation. Increased RGMa expression upregulated pro-inflammatory cytokine expression in microglia. Our observations suggest that the upregulation of RGMa is associated with the PD pathology; furthermore, inhibitory RGMa antibodies are a potential therapeutic option.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Doença de Parkinson/tratamento farmacológico , Animais , Modelos Animais de Doenças , Masculino , Camundongos
16.
Intern Med ; 60(1): 137-140, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32830177

RESUMO

In addition to muscle nicotinic acetylcholine receptor (AChR) and muscle-specific kinase (MuSK), low-density lipoprotein receptor (Lrp4) has recently been discovered to be a novel target antigen among patients with seronegative myasthenia gravis (MG). We herein report the findings of a 62-year-old patient who showed positivity for anti-MuSK, anti-Lrp4, and anti-titin antibodies. The patient developed MG crisis following a 10-year history of intermittent double vision with ptosis, and a 7-year history of dropped head. Our detailed clinical, laboratory, and therapeutic descriptions highlight its unique characteristics of anti-MuSK-antibody positive MG accompanied by anti-Lrp4 and anti-titin antibodies.


Assuntos
Miastenia Gravis , Receptores Nicotínicos , Autoanticorpos , Conectina , Humanos , Proteínas Relacionadas a Receptor de LDL , Pessoa de Meia-Idade , Miastenia Gravis/tratamento farmacológico , Receptores de LDL
17.
Neurotherapeutics ; 18(1): 460-473, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33083995

RESUMO

Go-sha-jinki-Gan (GJG) is a traditional Japanese herbal medicine. In clinical practice, GJG is effective against neuropathic pain and hypersensitivity induced by chemotherapy or diabetes. In our previous study using a chronic constriction injury mouse model, we showed that GJG inhibited microglia activation by suppressing the expression of tumor necrosis factor-α (TNF-α) and p38 mitogen-activated protein kinase (p38 MAPK) in the peripheral nervous system. To investigate whether GJG can suppress inflammation in the central nervous system (CNS) in the context of neurological disorders, we examined the effect of GJG on the activation of resident glial cells and on p38-TNF signaling in two mouse models of neurological disorders: the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinson's disease. GJG administration relieved the severity of clinical EAE symptoms and MPTP-induced inflammation by decreasing the number of microglia and the production of TNF-α in the spinal cord of EAE mice and the substantia nigra of MPTP-treated mice. Accordingly, GJG suppressed the phosphorylation of p38 in glial cells of these two mouse models. We conclude that GJG attenuates inflammation of the CNS by suppressing glial cell activation, followed by a decrease in the production of TNF-α via p38-TNF signaling.


Assuntos
Sistema Nervoso Central/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Transtornos Parkinsonianos/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Sistema Nervoso Central/efeitos dos fármacos , Feminino , Medicina Herbária/métodos , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
18.
FEBS Open Bio ; 11(2): 354-366, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33301617

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder caused by the selective loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc). Lewy bodies (LBs), another histological hallmark of PD, are observed in patients with familial or sporadic PD. The therapeutic potential of reducing the accumulation of α-synuclein, a major LB component, has been investigated, but it remains unknown whether the formation of LBs results in the loss of DA neurons. PARK4 patients exhibit multiplication of the α-synuclein gene (SNCA) without any pathological mutations, but their symptoms develop relatively early. Therefore, study of PARK4 might help elucidate the mechanism of α-synuclein aggregation. In this study, we investigated the dynamics of α-synuclein during the early stage of immature DA neurons, which were differentiated from human-induced pluripotent stem cells (hiPSCs) derived from either a PARK4 patient with SNCA triplication or a healthy donor. We observed increased α-synuclein accumulation in PARK4 hiPSC-derived DA neurons relative to those derived from healthy donor hiPSCs. Interestingly, α-synuclein accumulation disappeared over time in the PARK4 patient-derived DA neurons. Moreover, an SNCA-specific antisense oligonucleotide could reduce α-synuclein levels during the accumulation stage. These observations may help reveal the mechanisms that regulate α-synuclein levels, which may consequently be useful in the development of new therapies for patients with sporadic or familial PD.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Doença por Corpos de Lewy/patologia , Doença de Parkinson/patologia , alfa-Sinucleína/deficiência , Diferenciação Celular , Células Cultivadas , Variações do Número de Cópias de DNA , Neurônios Dopaminérgicos/efeitos dos fármacos , Duplicação Gênica , Voluntários Saudáveis , Humanos , Células-Tronco Pluripotentes Induzidas , Doença por Corpos de Lewy/genética , Doença de Parkinson/genética , Cultura Primária de Células , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
19.
Autophagy ; 17(10): 2962-2974, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33218272

RESUMO

Mitochondrial quality control, which is crucial for maintaining cellular homeostasis, has been considered to be achieved exclusively through mitophagy. Here we report an alternative mitochondrial quality control pathway mediated by extracellular mitochondria release. By performing time-lapse confocal imaging on a stable cell line with fluorescent-labeled mitochondria, we observed release of mitochondria from cells into the extracellular space. Correlative light-electron microscopy revealed that majority of the extracellular mitochondria are in free form and, on rare occasions, some are enclosed in membrane-surrounded vesicles. Rotenone- and carbonyl cyanide m-chlorophenylhydrazone-induced mitochondrial quality impairment promotes the extracellular release of depolarized mitochondria. Overexpression of PRKN (parkin RBR E3 ubiquitin protein ligase), which has a pivotal role in mitophagy regulation, suppresses the extracellular mitochondria release under basal and stress condition, whereas its knockdown exacerbates it. Correspondingly, overexpression of PRKN-independent mitophagy regulators, BNIP3 (BCL2 interacting protein 3) and BNIP3L/NIX (BCL2 interacting protein 3 like), suppress extracellular mitochondria release. Autophagy-deficient cell lines show elevated extracellular mitochondria release. These results imply that perturbation of mitophagy pathway prompts mitochondria expulsion. Presence of mitochondrial protein can also be detected in mouse sera. Sera of PRKN-deficient mice contain higher level of mitochondrial protein compared to that of wild-type mice. More importantly, fibroblasts and cerebrospinal fluid samples from Parkinson disease patients carrying loss-of-function PRKN mutations show increased extracellular mitochondria compared to control subjects, providing evidence in a clinical context. Taken together, our findings suggest that extracellular mitochondria release is a comparable yet distinct quality control pathway from conventional mitophagy.Abbreviations: ACTB: actin beta; ANXA5: annexin A5; ATP5F1A/ATP5A: ATP synthase F1 subunit alpha; ATG: autophagy related; BNIP3: BCL2 interacting protein 3; BNIP3L/NIX: BCL2 interacting protein 3 like; CCCP: carbonyl cyanide m-chlorophenylhydrazone; CM: conditioned media; CSF: cerebrospinal fluid; DMSO: dimethyl sulfoxide; EM: electron microscopy; HSPD1/Hsp60: heat shock protein family D (Hsp60) member 1; KD: knockdown; KO: knockout; MAP1LC3A/LC3: microtubule associated protein 1 light chain 3 alpha; MT-CO1: mitochondrially encoded cytochrome c oxidase I; NDUFB8: NADH:ubiquinone oxidoreductase subunit B8; OE: overexpression; OPA1: OPA1 mitochondrial dynamin like GTPase; OXPHOS: oxidative phosphorylation; PBS: phosphate-buffered saline; PB: phosphate buffer; PD: Parkinson disease; PINK1: PTEN induced kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; RB1CC1/FIP200: RB1 inducible coiled-coil 1; SDHB: succinate dehydrogenase complex iron sulfur subunit B; TOMM20: translocase of outer mitochondrial membrane 20; TOMM40: translocase of outer mitochondrial membrane 40; UQCRC2: ubiquinol-cytochrome c reductase core protein 2; WT: wild-type.


Assuntos
Autofagia , Mitofagia , Animais , Autofagia/fisiologia , Humanos , Camundongos , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/genética , Ubiquitina-Proteína Ligases/metabolismo
20.
Rinsho Shinkeigaku ; 60(10): 712-715, 2020 Oct 24.
Artigo em Japonês | MEDLINE | ID: mdl-32893243

RESUMO

A 50-year-old woman developed gait disturbances and dysarthria since the past 2 years. She also presented with dystonia and hypokinesia of her left lower limb, and orthostatic hypotension. The dopamine transporter SPECT with 123I ioflupane showed abnormal scans in bilateral striatum. Cerebral MRI revealed atrophy and signal changes in the medulla and spinal cord, from which Alexander disease (AxD) was suspected. Consequently, we checked the Glial fibrillary acidic protein (GFAP) gene. The analysis of the gene detected a heterozygous c.219G>T mutation, which was the first mutation reported in Japan, and finally she was diagnosed with AxD. Dystonia is relatively rare in AxD patients, but this case demonstrated that AxD should be listed in the differential diagnosis of extrapyramidal syndromes with abnormalities of the medulla and spinal cord on MRI.


Assuntos
Doença de Alexander/diagnóstico , Proteínas da Membrana Plasmática de Transporte de Dopamina , Dopamina/metabolismo , Distonia/etiologia , Extremidade Inferior , Tomografia Computadorizada de Emissão de Fóton Único , Doença de Alexander/complicações , Doença de Alexander/diagnóstico por imagem , Doença de Alexander/metabolismo , Diagnóstico Diferencial , Distonia/diagnóstico por imagem , Feminino , Proteína Glial Fibrilar Ácida/genética , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Mutação
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