Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Mais filtros

Base de dados
Intervalo de ano de publicação
Mol Neurobiol ; 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34984583


Parkinson's disease (PD) is an incurable neurodegenerative disease characterized by aggregation of pathological alpha-synuclein (α-syn) and loss of dopaminergic neuron in the substantia nigra. Inhibition of phosphorylation of the α-syn has been shown to mediate alleviation of PD-related pathology. Protein phosphatase 2A (PP2A), an important serine/threonine phosphatase, plays an essential role in catalyzing dephosphorylation of the α-syn. Here, we identified and validated cancerous inhibitor of PP2A (CIP2A), as a potential diagnostic biomarker for PD. Our data showed that plasma CIP2A concentrations in PD patients were significantly lower compared to age- and sex-matched controls, 1.721 (1.435-2.428) ng/ml vs 3.051(2.36-5.475) ng/ml, p < 0.0001. The area under the curve of the plasma CIP2A in distinguishing PD from the age- and sex-matched controls was 0.776. In addition, we evaluated the role of CIP2A in PD-related pathogenesis in PD cellular and MPTP-induced mouse model. The results demonstrated that CIP2A is upregulated in PD cellular and MPTP-induced mouse models. Besides, suppression of the CIP2A expression alleviates rotenone induced aggregation of the α-syn as well as phosphorylation of the α-syn in SH-SY5Y cells, which is associated with increased PP2A activity. Taken together, our data demonstrated that CIP2A plays an essential role in the mechanisms related to PD development and might be a novel PD biomarker.

Front Immunol ; 12: 719807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691027


According to emerging studies, the excessive activation of microglia and the subsequent release of pro-inflammatory cytokines play important roles in the pathogenesis and progression of Parkinson's disease (PD). However, the exact mechanisms governing chronic neuroinflammation remain elusive. Findings demonstrate an elevated level of NLRP3 inflammasome in activated microglia in the substantia nigra of PD patients. Activated NLRP3 inflammasome aggravates the pathology and accelerates the progression of neurodegenerative diseases. Abnormal protein aggregation of α-synuclein (α-syn), a pathologically relevant protein of PD, were reported to activate the NLRP3 inflammasome of microglia through interaction with toll-like receptors (TLRs). This eventually releases pro-inflammatory cytokines through the translocation of nuclear factor kappa-B (NF-κB) and causes an impairment of mitochondria, thus damaging the dopaminergic neurons. Currently, therapeutic drugs for PD are primarily aimed at providing relief from its clinical symptoms, and there are no well-established strategies to halt or reverse this disease. In this review, we aimed to update existing knowledge on the role of the α-syn/TLRs/NF-κB/NLRP3 inflammasome axis and microglial activation in PD. In addition, this review summarizes recent progress on the α-syn/TLRs/NF-κB/NLRP3 inflammasome axis of microglia as a potential target for PD treatment by inhibiting microglial activation.

Front Aging Neurosci ; 13: 657095, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393753


The pathogenesis of Parkinson's disease (PD) is currently unclear. Recent studies have suggested a correlation between vitamin D and PD. Vitamin D and its analogs have protective effects in animal models of PD, but these studies have not clarified the mechanism. Parthanatos is a distinct type of cell death caused by excessive activation of poly (ADP-ribose) polymerase-1 (PARP1), and the activation of PARP1 in PD models suggests that parthanatos may exist in PD pathophysiology. 1,25-Dihydroxyvitamin D3 (calcitriol) is a potential inhibitor of PARP1 in macrophages. This study aimed to investigate whether calcitriol treatment improves PD models and its effects on the parthanatos pathway. A 1-methyl-4-phenylpyridinium (MPP+)-induced cell model and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) subacute animal model were selected as the in vitro and in vivo PD models, and calcitriol was applied in these models. Results showed that parthanatos existed in the MPP+-induced cell model and pretreatment with calcitriol improved cell viability, reduced the excessive activation of PARP1, and relieved parthanatos. The application of calcitriol in the MPTP subacute animal model also improved behavioral tests, restored the damage to dopamine neurons, and reduced the activation of PARP1-related signaling pathways. To verify whether calcitriol interacts with PARP1 through its vitamin D receptor (VDR), siRNA, and overexpression plasmids were used to downregulate or overexpress VDR. Following the downregulation of VDR, the expression and activation of PARP1 increased and PARP1 was inhibited when VDR was overexpressed. Coimmunoprecipitation verified the combination of VDR and PARP1. In short, calcitriol can substantially improve parthanatos in the MPP+-induced cell model and MPTP model, and the protective effect might be partly through the VDR/PARP1 pathway, which provides a new possibility for the treatment of PD.

Brain ; 144(7): 2024-2037, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-33792662


Increasing evidence suggests that microglial activation is strongly linked to the initiation and progression of Parkinson's disease. Cell-to-cell propagation of α-synuclein pathology is a highlighted feature of Parkinson's disease, and the focus of such research has been primarily on neurons. However, recent studies as well as the data contained herein suggest that microglia, the primary phagocytes in the brain, play a direct role in the spread of α-synuclein pathology. Recent data revealed that plasma exosomes derived from Parkinson's disease patients (PD-EXO) carry pathological α-synuclein and target microglia preferentially. Hence, PD-EXO are likely a key tool for investigating the role of microglia in α-synuclein transmission. We showed that intrastriatal injection of PD-EXO resulted in the propagation of exosomal α-synuclein from microglia to neurons following microglia activation. Toll-like receptor 2 (TLR2) in microglia was activated by exosomal α-synuclein and acted as a crucial mediator of PD-EXO-induced microglial activation. Additionally, partial microglia depletion resulted in a significant decrease of exogenous α-synuclein in the substantia nigra. Furthermore, exosomal α-synuclein internalization was initiated by binding to TLR2 of microglia. Excessive α-synuclein phagocytosis may induce the inflammatory responses of microglia and provide the seed for microglia-to-neuron transmission. Consistently, TLR2 silencing in microglia mitigated α-synuclein pathology in vivo. Overall, the present data support the idea that the interaction of exosomal α-synuclein and microglial TLR2 contribute to excessive α-synuclein phagocytosis and microglial activation, which lead to the further propagation and spread of α-synuclein pathology, thereby highlighting the pivotal roles of reactive microglia in α-synuclein transmission.

Exossomos/metabolismo , Microglia/metabolismo , Doença de Parkinson/metabolismo , Receptor 2 Toll-Like/metabolismo , alfa-Sinucleína/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/patologia , Doença de Parkinson/patologia , Ratos , Ratos Sprague-Dawley
Sleep Med ; 75: 428-433, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32980664


BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is adversely affecting sleep quality and mental health, especially in individuals with chronic disease such as Parkinson's disease (PD). METHODS: We conducted a quantitative study, which included 119 Chinese PD patients who had been treated in an outpatient neurology clinic in Wuhan and 169 age- and sex-matched healthy controls. The questionnaire survey focused on the impact of the COVID-19 pandemic on sleep, mental status, symptoms, and daily life and medical treatment of PD patients. RESULTS: Compared to healthy controls, PD patients had significantly higher scores in both the Pittsburgh Sleep Quality Index (PSQI) (8.13 vs 5.36, p < 0.001) and the Hospital Anxiety and Depression Scale (HADS) -Depression (4.89 vs 3.82, p = 0.022), as well as a higher prevalence of sleep disturbances with PSQI > 5 points (68.9% vs 44.4%, p < 0.001). Sleep disturbance was identified in 68.9% of PD patients. A logistic regression analysis showed that sleep disturbance of PD patients was independently associated with exacerbation of PD symptoms (OR = 3.616, 95%CI= (1.479, 8.844), p = 0.005) and anxiety (OR = 1.379, 95%CI= (1.157, 1.642), p < 0.001). Compared to male PD patients, female ones had higher PSQI scores (9.28 ± 4.41 vs 7.03 ± 4.01, p = 0.009) and anxiety (32.8% vs 0.1%, p = 0.002) and depression prevalence (34.5% vs 11.5%, p = 0.003). CONCLUSION: The findings of the present study emphasize the importance of mental and sleep health interventions in PD patients during the COVID-19 pandemic. Additional attention should be paid to the difficulty encountered by PD patients in seeking medical treatment.

Ansiedade/epidemiologia , COVID-19/psicologia , Depressão/epidemiologia , Pandemias , Doença de Parkinson/epidemiologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Idoso , Estudos de Casos e Controles , China , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia , Pesquisa Qualitativa , Inquéritos e Questionários
Int J Mol Sci ; 17(5)2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27153061


Glioblastoma (GBM) is the most common primary brain tumor, with poor prognosis and a lack of effective therapeutic options. The aberrant expression of transcription factor REST (repressor element 1-silencing transcription factor) had been reported in different kinds of tumors. However, the function of REST and its mechanisms in GBM remain elusive. Here, REST expression was inhibited by siRNA silencing in U-87 and U-251 GBM cells. Then CCK-8 assay showed significantly decreased cell proliferation, and the inhibition of migration was verified by scratch wound healing assay and transwell assay. Using cell cycle analysis and Annexin V/PI straining assay, G1 phase cell cycle arrest was found to be a reason for the suppression of cell proliferation and migration upon REST silencing, while apoptosis was not affected by REST silencing. Further, the detection of REST-downstream genes involved in cytostasis and migration inhibition demonstrated that CCND1 and CCNE1 were reduced; CDK5R1, BBC3, EGR1, SLC25A4, PDCD7, MAPK11, MAPK12, FADD and DAXX were enhanced, among which BBC3 and DAXX were direct targets of REST, as verified by ChIP (chromatin immunoprecipitation) and Western blotting. These data suggested that REST is a master regulator that maintains GBM cells proliferation and migration, partly through regulating cell cycle by repressing downstream genes, which might represent a potential target for GBM therapy.

Movimento Celular , Proliferação de Células , Glioblastoma/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Proteínas Correpressoras , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina E/genética , Ciclina E/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Proteína de Domínio de Morte Associada a Fas/genética , Proteína de Domínio de Morte Associada a Fas/metabolismo , Fase G1 , Humanos , Proteínas de Membrana Transportadoras , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Chaperonas Moleculares , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/genética