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1.
Acta Pharmacol Sin ; 45(1): 36-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37684382

RESUMO

The gut-brain axis plays a vital role in Parkinson's disease (PD). The mechanisms of gut-brain transmission mainly focus on α-synuclein deposition, intestinal inflammation and microbiota function. A few studies have shown the trigger of PD pathology in the gut. α-Synuclein is highly conserved in food products, which was able to form ß-folded aggregates and to infect the intestinal mucosa. In this study we investigated whether α-synuclein-preformed fibril (PFF) exposure could modulate the intestinal environment and induce rodent models replicating PD pathology. We first showed that PFF could be internalized into co-cultured Caco-2/HT29/Raji b cells in vitro. Furthermore, we demonstrated that PFF perfusion caused the intestinal inflammation and activation of enteric glial cells in an ex vivo intestinal organ culture and in an in vivo intestinal mouse coloclysis model. Moreover, we found that PFF exposure through regular coloclysis induced PD pathology in wild-type (WT) and A53T α-synuclein transgenic mice with various phenotypes. Particularly in A53T mice, PFF induced significant behavioral disorders, intestinal inflammation, α-synuclein deposition, microbiota dysbiosis, glial activation as well as degeneration of dopaminergic neurons in the substantia nigra. In WT mice, however, the PFF induced only mild behavioral abnormalities, intestinal inflammation, α-synuclein deposition, and glial activation, without significant changes in microbiota and dopaminergic neurons. Our results reveal the possibility of α-synuclein aggregates binding to the intestinal mucosa and modeling PD in mice. This study may shed light on the investigation and early intervention of the gut-origin hypothesis in neurodegenerative diseases.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Camundongos , Animais , alfa-Sinucleína/metabolismo , Células CACO-2 , Transtornos Parkinsonianos/metabolismo , Doença de Parkinson/metabolismo , Camundongos Transgênicos , Neurônios Dopaminérgicos/metabolismo , Inflamação/metabolismo
2.
Sensors (Basel) ; 23(18)2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37765992

RESUMO

Access Control Policies (ACPs) are essential for ensuring secure and authorized access to resources in IoT networks. Recognizing these policies involves identifying relevant statements within project documents expressed in natural language. While current research focuses on improving recognition accuracy through algorithm enhancements, the challenge of limited labeled data from individual clients is often overlooked, which impedes the training of highly accurate models. To address this issue and harness the potential of IoT networks, this paper presents FL-Bert-BiLSTM, a novel model that combines federated learning and pre-trained word embedding techniques for access control policy recognition. By leveraging the capabilities of IoT networks, the proposed model enables real-time and distributed training on IoT devices, effectively mitigating the scarcity of labeled data and enhancing accessibility for IoT applications. Additionally, the model incorporates pre-trained word embeddings to leverage the semantic information embedded in textual data, resulting in improved accuracy for access control policy recognition. Experimental results substantiate that the proposed model not only enhances accuracy and generalization capability but also preserves data privacy, making it well-suited for secure and efficient access control in IoT networks.

3.
Comput Intell Neurosci ; 2023: 8389193, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909969

RESUMO

With the continuous development of computer technology, many institutions in society have higher requirements for the efficiency and reliability of identification systems. In sectors with a high-security level, the use of traditional key and smart card system has been replaced by the identification system of biometric technology. The use of fingerprint and face recognition in biometric technology is a biometric technology that does not constitute an infringement on the human body and is convenient and reliable. The biometric technology has been continuously improved, and the existing biometric technologies are based on unimodal biometric features. The unimodal biometric technology has its own limitations such as proposing single information and checking data affected by the environment, which makes it difficult for the technology to play its advantages in practical applications. In this paper, we use CNN-SRU deep learning to preprocess a large amount of complex data in the perceptual layer. The data collected in the perceptual layer are first transmitted to CNN convolutional neural network for simple classification and analysis and then arrives at the LSTM session to update again and optimize the screening to improve the biometric performance. The results show that the CNN-LSTM, CNN-GRU, and CNN algorithms show a decreasing trend in accuracy under the three error evaluation criteria of RMSE, MAE, and ME, from 0.35 to 0.07, 0.58 to 0.19, and 0.38 to 0.15, respectively. The recognition rate of multifeature fusion can reach 95.2%; the recognition efficiency of the multibiometric authentication system and accuracy rate has been significantly improved. It provides a strong guarantee for the regional standardization, high integration, generalization, and modularization of multibiometric identification system application products.


Assuntos
Identificação Biométrica , Humanos , Reprodutibilidade dos Testes , Identificação Biométrica/métodos , Redes Neurais de Computação , Algoritmos , Biometria/métodos
4.
Acta Pharmacol Sin ; 44(6): 1122-1134, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36627343

RESUMO

Aggregation of α-synuclein, a component of Lewy bodies (LBs) or Lewy neurites in Parkinson's disease (PD), is strongly linked with disease development, making it an attractive therapeutic target. Inhibiting aggregation can slow or prevent the neurodegenerative process. However, the bottleneck towards achieving this goal is the lack of such inhibitors. In the current study, we established a high-throughput screening platform to identify candidate compounds for preventing the aggregation of α-synuclein among the natural products in our in-house compound library. We found that a small molecule, 03A10, i.e., (+)-desdimethylpinoresinol, which is present in the fruits of Vernicia fordii (Euphorbiaceae), modulated aggregated α-synuclein, but not monomeric α-synuclein, to prevent further elongation of α-synuclein fibrils. In α-synuclein-overexpressing cell lines, 03A10 (10 µM) efficiently prevented α-synuclein aggregation and markedly ameliorated the cellular toxicity of α-synuclein fibril seeds. In the MPTP/probenecid (MPTP/p) mouse model, oral administration of 03A10 (0.3 mg· kg-1 ·d-1, 1 mg ·kg-1 ·d-1, for 35 days) significantly alleviated behavioral deficits, tyrosine hydroxylase (TH) neuron degeneration and p-α-synuclein aggregation in the substantia nigra (SN). As the Braak hypothesis postulates that the prevailing site of early PD pathology is the gastrointestinal tract, we inoculated α-synuclein preformed fibrils (PFFs) into the mouse colon. We demonstrated that α-synuclein PFF inoculation promoted α-synuclein pathology and neuroinflammation in the gut and brain; oral administration of 03A10 (5 mg· kg-1 ·d-1, for 4 months) significantly attenuated olfactory deficits, α-synuclein accumulation and neuroinflammation in the olfactory bulb and SN. We conclude that 03A10 might be a promising drug candidate for the treatment of PD. 03A10 might be a novel drug candidate for PD treatment, as it inhibits α-synuclein aggregation by modulating aggregated α-synuclein rather than monomeric α-synuclein to prevent further elongation of α-synuclein fibrils and prevent α-synuclein toxicity in vitro, in an MPTP/p mouse model, and PFF-inoculated mice.


Assuntos
Doença de Parkinson , Camundongos , Animais , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo , Doenças Neuroinflamatórias , Substância Negra/metabolismo , Substância Negra/patologia , Encéfalo/metabolismo
5.
Biochem Biophys Res Commun ; 611: 23-30, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35472607

RESUMO

Dementia with Lewy bodies (DLB) is the second most common type of neurodegenerative dementia after Alzheimer's disease (AD). Neuroinflammation plays an important role in neurodegenerative diseases. It is urgent to unravel the pathogenesis of DLB and find potential therapeutic drugs. Here, we investigated the pharmacological effects of the NLRP3 inflammasome inhibitor MCC950 in A53T α-synuclein transgenic line M83 mice aged 4 months. The behavioral tests including Y-maze, Barnes maze, nest building and Rotarod showed that MCC950 significantly improved the cognitive dysfunction symptom without affecting the motor coordination after consecutive intragastric administration every day for 5 weeks. Furthermore, immunostaining or immunoblotting experiments on the hippocampal tissue were performed, and the results suggested that MCC950 not only inhibited the expression of NLRP3, and suppressed the activation of astrocytes and microglia, but also promoted the mTOR-mediated autophagy pathway to reduce human α-synuclein accumulation. Our findings further demonstrate that line M83 mice may be used as an animal model for DLB research, and can provide preclinical evidences for the development of MCC950 as a promising therapeutic drug.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Animais , Modelos Animais de Doenças , Furanos , Hipocampo/metabolismo , Indenos , Doença por Corpos de Lewy/metabolismo , Camundongos , Camundongos Transgênicos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Sulfonamidas , alfa-Sinucleína/metabolismo
6.
Pharmacol Res ; 150: 104538, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707034

RESUMO

The human A53T mutant of α-synuclein tends to aggregate and leads to neurotoxicity in familial Parkinson's disease (PD). The aggregation of α-synuclein is also found in sporadic PD. Thus, targeting α-synuclein clearance could be used as a drug-discovery strategy for PD treatment. Caffeic acid (CA) has shown neuroprotection in Alzheimer's disease or cerebral ischaemia; however, it is unclear whether CA confers neuroprotection in α-synuclein-induced PD models. Here we focus on whether and how A53T α-synuclein is affected by CA. We assessed the effect of CA on cell viability in SH-SY5Y cells overexpressing A53T α-synuclein. Pathway-related inhibitors were used to identify the autophagy mechanisms. Seven-month-old A53T α-synuclein transgenic mice (A53T Tg mice) received CA daily for eight consecutive weeks. Behaviour tests including the buried food pellet test, the pole test, the Rotarod test, open field analysis, and gait analysis were used to evaluate the neuroprotective effect of CA. Tyrosine hydroxylase and α-synuclein were assessed by immunohistochemistry or western blot in the substantia nigra (SN). We found that CA alleviated the cell damage induced by overexpressing A53T α-synuclein and that CA reduced A53T α-synuclein by activating the JNK/Bcl-2-mediated autophagy pathway. The efficacy of CA on A53T α-synuclein degradation was reversed by the autophagy inhibitor bafilomycin A1 and the JNK inhibitor SP600125. In A53T Tg mice, CA improved behavioural impairments, attenuated loss of dopaminergic neurons, enhanced autophagy and reduced α-synuclein in the SN. Thus, the results provide scientific evidence for the neuroprotective effect of CA in PD. Our work lays the foundation for CA clinical trials to treat PD in the future.


Assuntos
Ácidos Cafeicos/farmacologia , Ácidos Cafeicos/uso terapêutico , MAP Quinase Quinase 4/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Transtornos Parkinsonianos/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , alfa-Sinucleína/metabolismo , Animais , Autofagia/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Marcha/efeitos dos fármacos , Humanos , Masculino , Camundongos Transgênicos , Doença de Parkinson , Transtornos Parkinsonianos/metabolismo , alfa-Sinucleína/genética
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