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1.
Chem Rev ; 123(21): 12254-12311, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37874548

RESUMO

Protein misfolding and aggregation, a key contributor to the progression of numerous neurodegenerative diseases, results in functional deficiencies and the creation of harmful intermediates. Detailed visualization of this misfolding process is of paramount importance for improving our understanding of disease mechanisms and for the development of potential therapeutic strategies. While in vitro studies using purified proteins have been instrumental in delivering significant insights into protein misfolding, the behavior of these proteins in the complex milieu of living cells often diverges significantly from such simplified environments. Biomedical imaging performed in cell provides cellular-level information with high physiological and pathological relevance, often surpassing the depth of information attainable through in vitro methods. This review highlights a variety of methodologies used to scrutinize protein misfolding within biological systems. This includes optical-based methods, strategies leaning on mass spectrometry, in-cell nuclear magnetic resonance, and cryo-electron microscopy. Recent advancements in these techniques have notably deepened our understanding of protein misfolding processes and the features of the resulting misfolded species within living cells. The progression in these fields promises to catalyze further breakthroughs in our comprehension of neurodegenerative disease mechanisms and potential therapeutic interventions.


Assuntos
Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/diagnóstico por imagem , Doenças Neurodegenerativas/metabolismo , Dobramento de Proteína , Microscopia Crioeletrônica , Proteínas/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-38490452

RESUMO

OBJECTIVE: To systematically evaluate the effect of contralaterally controlled functional electrical stimulation (CCFES) on motor function after acquired brain injury (ABI). DATA SOURCES: We searched the PubMed, Embase, Cochrane Central Register of Controlled Trials, Physiotherapy Evidence Database (PEDro), Web of Science, SinoMed, CNKI, VIP Database for Chinese Technical Periodicals and Wanfang Database, from inception to December 2023. STUDY SELECTION: Studies were included if they were randomized controlled trials assessing the effect of CCFES on motor function compared with routine rehabilitation or routine electrical stimulation after ABI. Two independent reviewers screened 894 articles for inclusion. DATA EXTRACTION: The extracted data included study information, sample size, study population, interventions, measurement evaluated, and the test interval. DATA SYNTHESIS: This study included 24 trials with 28 intervention-control pairs and 1148 participants with stroke. Meta-analysis showed that the CCFES group demonstrated more significant improvement than the control group in the Fugl-Meyer Assessment Scale (FMA) (standardized mean difference [SMD]=0.66, 95% confidence interval [CI]=0.44-0.88, P<.001), active range of motion (AROM) (SMD=0.77, 95% CI=0.54-1.01, P<.001), modified Barthel Index (MBI) (SMD=0.55, 95% CI=0.29-0.81, P<.001), Motricity Index (MI) (SMD=0.60, 95% CI=0.26-0.94, P<.001) surface electromyography (sEMG) (SMD=0.81, 95% CI=0.56-1.06, P<.001), and Functional Ambulation Category (FAC) (SMD=0.53, 95% CI=0.24-0.83, P<.001). The CCFES group showed no significant improvement over the control group in the Action Research Arm Test (ARAT) (SMD=0.24, 95% CI=-0.10-0.58, P=.17). CONCLUSIONS: Our synthesized evidence suggests that CCFES could improve motor function in patients with stroke. More RCTs with other patients with brain injury are required to provide future evidence on the therapy effect of CCFES and make a contribution to the uniform standard of CCFES.

3.
Int J Mol Sci ; 25(14)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39062916

RESUMO

Schizophrenia is a serious mental disease that is regulated by multiple genes and influenced by multiple factors. Due to the complexity of its etiology, the pathogenesis is still unclear. MicroRNAs belong to a class of small non-coding RNAs that are highly conserved in endogenous evolution and play critical roles in multiple biological pathways. In recent years, aberrant miRNA expression has been implicated in schizophrenia, with certain miRNAs emerging as potential diagnostic and prognostic biomarkers for this disorder. In this review, our objective is to investigate the differential expression of miRNAs in schizophrenia, elucidate their potential mechanisms of action, and assess their feasibility as biomarkers. The PubMed electronic database and Google Scholar were searched for the years 2003 to 2024. The study focused on schizophrenia and miRNA as the research topic, encompassing articles related to biomarkers, etiology, action mechanisms, and differentially expressed genes associated with schizophrenia and miRNA. A total of 1488 articles were retrieved, out of which 49 were included in this scope review. This study reviewed 49 articles and identified abnormal expression of miRNA in different tissues of both schizophrenia patients and healthy controls, suggesting its potential role in the pathogenesis and progression of schizophrenia. Notably, several specific miRNAs, including miR-34a, miR-130b, miR-193-3p, miR-675-3p, miR-1262, and miR-218-5p, may serve as promising biological markers for diagnosing schizophrenia. Furthermore, this study summarized potential mechanisms through which miRNAs may contribute to the development of schizophrenia. The studies within the field of miRNA's role in schizophrenia encompass a broad spectrum of focus. Several selected studies have identified dysregulated miRNAs associated with schizophrenia across various tissues, thereby highlighting the potential utility of specific miRNAs as diagnostic biomarkers for this disorder. Various mechanisms underlying dysregulated miRNAs in schizophrenia have been explored; however, further investigations are needed to determine the exact mechanisms by which these dysregulated miRNAs contribute to the pathogenesis of this condition. The exploration of miRNA's involvement in the etiology and identification of biomarkers for schizophrenia holds significant promise in informing future clinical trials and advancing our understanding in this area.


Assuntos
Biomarcadores , MicroRNAs , Esquizofrenia , Esquizofrenia/genética , Esquizofrenia/metabolismo , Humanos , MicroRNAs/genética , Regulação da Expressão Gênica
4.
Neurobiol Dis ; 179: 106064, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878327

RESUMO

Stroke is a major cause of mortality and morbidity and most acute strokes are ischemic. Evidence-based medicine has demonstrated the effectiveness of constraint-induced movement therapy (CIMT) in the recovery of motor function in patients after ischemic stroke, but the specific treatment mechanism remains unclear. Herein, our integrated transcriptomics and multiple enrichment analysis studies, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analysis (GSEA) studies show that CIMT conduction broadly curtails immune response, neutrophil chemotaxis, and chemokine-mediated signaling pathway, CCR chemokine receptor binding. Those suggest the potential effect of CIMT on neutrophils in ischemic mice brain parenchyma. Recent studies have found that accumulating granulocytes release extracellular web-like structures composed of DNA and proteins called neutrophil extracellular traps (NETs), which destruct neurological function primarily by disrupting the blood-brain barrier and promoting thrombosis. However, the temporal and spatial distribution of neutrophils and their released NETs in parenchyma and their damaging effects on nerve cells remain unclear. Thus, utilizing immunofluorescence and flow cytometry, our analyses uncovered that NETs erode multiple regions such as primary motor cortex (M1), striatum (Str), nucleus of the vertical limb of the diagonal band (VDB), nucleus of the horizontal limb of the diagonal band (HDB) and medial septal nucleus (MS), and persist in the brain parenchyma for at least 14 days, while CIMT can reduce the content of NETs and chemokines CCL2 and CCL5 in M1. Intriguingly, CIMT failed to further reduce neurological deficits after inhibiting the NET formation by pharmacologic inhibition of peptidylarginine deiminase 4 (PAD4). Collectively, these results demonstrate that CIMT could alleviate cerebral ischemic injury induced locomotor deficits by modulating the activation of neutrophils. These data are expected to provide direct evidence for the expression of NETs in ischemic brain parenchyma and novel insights into the mechanisms of CIMT protecting against ischemic brain injury.


Assuntos
Terapia por Exercício , Armadilhas Extracelulares , Transtornos Motores , Acidente Vascular Cerebral , Animais , Camundongos , Encéfalo/metabolismo , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/fisiologia , Transtornos Motores/metabolismo , Transtornos Motores/terapia , Neutrófilos , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/terapia
5.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32844230

RESUMO

Alternative polyadenylation (APA) in breast tumor samples results in the removal/addition of cis-regulatory elements such as microRNA (miRNA) target sites in the 3'-untranslated region (3'-UTRs) of genes. Although previous computational APA studies focused on a subset of genes strongly affected by APA (APA genes), we identify miRNAs of which widespread APA events collectively increase or decrease the number of target sites [probabilistic inference of microRNA target site modification through APA (PRIMATA-APA)]. Using PRIMATA-APA on the cancer genome atlas (TCGA) breast cancer data, we found that the global APA events change the number of the target sites of particular microRNAs [target sites modified miRNA (tamoMiRNA)] enriched for cancer development and treatments. We also found that when knockdown (KD) of NUDT21 in HeLa cells induces a different set of widespread 3'-UTR shortening than TCGA breast cancer data, it changes the target sites of the common tamoMiRNAs. Since the NUDT21 KD experiment previously demonstrated the tumorigenic role of APA events in a miRNA dependent fashion, this result suggests that the APA-initiated tumorigenesis is attributable to the miRNA target site changes, not the APA events themselves. Further, we found that the miRNA target site changes identify tumor cell proliferation and immune cell infiltration to the tumor microenvironment better than the miRNA expression levels or the APA events themselves. Altogether, our computational analyses provide a proof-of-concept demonstration that the miRNA target site information indicates the effect of global APA events with a potential as predictive biomarker.


Assuntos
Regiões 3' não Traduzidas/genética , Neoplasias da Mama/genética , MicroRNAs/genética , Poliadenilação/genética , Evasão Tumoral/genética , Algoritmos , Sítios de Ligação/genética , Neoplasias da Mama/metabolismo , Proliferação de Células/genética , Fator de Especificidade de Clivagem e Poliadenilação/genética , Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Modelos Genéticos , RNA-Seq/métodos , Microambiente Tumoral/genética
6.
PLoS Pathog ; 17(4): e1009041, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33914843

RESUMO

Epstein-Barr virus (EBV) is a ubiquitous γ-herpesvirus with latent and lytic cycles. EBV replicates in the stratified epithelium but the nasopharynx is also composed of pseudostratified epithelium with distinct cell types. Latent infection is associated with nasopharyngeal carcinoma (NPC). Here, we show with nasopharyngeal conditionally reprogrammed cells cultured at the air-liquid interface that pseudostratified epithelial cells are susceptible to EBV infection. Donors varied in susceptibility to de novo EBV infection, but susceptible cultures also displayed differences with respect to pathogenesis. The cultures from one donor yielded lytic infection but cells from two other donors were positive for EBV-encoded EBERs and negative for other lytic infection markers. All cultures stained positive for the pseudostratified markers CK7, MUC5AC, α-tubulin in cilia, and the EBV epithelial cell receptor Ephrin receptor A2. To define EBV transcriptional programs by cell type and to elucidate latent/lytic infection-differential changes, we performed single cell RNA-sequencing on one EBV-infected culture that resulted in alignment with many EBV transcripts. EBV transcripts represented a small portion of the total transcriptome (~0.17%). All cell types in the pseudostratified epithelium had detectable EBV transcripts with suprabasal cells showing the highest number of reads aligning to many EBV genes. Several restriction factors (IRF1, MX1, STAT1, C18orf25) known to limit lytic infection were expressed at lower levels in the lytic subcluster. A third of the differentially-expressed genes in NPC tumors compared to an uninfected pseudostratified ALI culture overlapped with the differentially-expressed genes in the latent subcluster. A third of these commonly perturbed genes were specific to EBV infection and changed in the same direction. Collectively, these findings suggest that the pseudostratified epithelium could harbor EBV infection and that the pseudostratified infection model mirrors many of the transcriptional changes imposed by EBV infection in NPC.


Assuntos
Células Epiteliais/virologia , Infecções por Vírus Epstein-Barr/virologia , Interações Hospedeiro-Patógeno/imunologia , Neoplasias Nasofaríngeas/virologia , Carcinoma/metabolismo , Carcinoma/virologia , Células Epiteliais/metabolismo , Epitélio/metabolismo , Epitélio/virologia , Infecções por Vírus Epstein-Barr/metabolismo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Humanos , Carcinoma Nasofaríngeo/virologia , RNA Viral/genética
7.
Cell Mol Neurobiol ; 43(4): 1487-1497, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35917043

RESUMO

Stroke is a common cerebrovascular disease with high morbidity, mortality, and disability worldwide. Post-stroke dysfunction is related to the death of neurons and impairment of synaptic structure, which results from cerebral ischemic damage. Currently, transcranial magnetic stimulation (TMS) techniques are available to provide clinically effective interventions and quantitative diagnostic and prognostic biomarkers. The development of TMS has been 40 years and a range of repetitive TMS (rTMS) protocols are now available to regulate neuronal plasticity in many neurological disorders, such as stroke, Parkinson disease, psychiatric disorders, Alzheimer disease, and so on. Basic studies in an animal model with ischemic stroke are significant for demonstrating potential mechanisms of neural restoration induced by rTMS. In this review, the mechanisms were summarized, involving synaptic plasticity, neural cell death, neurogenesis, immune response, and blood-brain barrier (BBB) disruption in vitro and vivo experiments with ischemic stroke models. Those findings can contribute to the understanding of how rTMS modulated function recovery and the exploration of novel therapeutic targets. The mechanisms of rTMS in treating ischemic stroke from animal models. rTMS can prompt synaptic plasticity by increasing NMDAR, AMPAR and BDNF expression; rTMS can inhibit pro-inflammatory cytokines TNF and facilitate the expression of anti-inflammatory cytokines IL-10 by shifting astrocytic phenotypes from A1 to A2, and shifting microglial phenotypes from M1 to M2; rTMS facilitated the release of angiogenesis-related factors TGFß and VEGF in A2 astrocytes, which can contribute to vasculogenesis and angiogenesis; rTMS can suppress apoptosis by increasing Bcl-2 expression and inhibiting Bax, caspase-3 expression; rTMS can also suppress pyroptosis by decreasing caspase-1, IL-1ß, ASC, GSDMD and NLRP1 expression. rTMS, repetitive transcranial magnetic stimulation; NMDAR, N-methyl-D-aspartic acid receptors; AMPAR: α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors; BDNF, brain-derived neurotrophic factor; VEGF, vascular endothelial growth factor; GSDMD: cleaved Caspase-1 cleaves Gasdermin D; CBF: cerebral blood flow.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Animais , Estimulação Magnética Transcraniana/métodos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , AVC Isquêmico/terapia , Encéfalo/metabolismo , Acidente Vascular Cerebral/terapia , Modelos Animais de Doenças , Caspases/metabolismo
8.
Nonlinear Dyn ; 111(2): 1485-1510, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36246669

RESUMO

A crucial challenge encountered in diverse areas of engineering applications involves speculating the governing equations based upon partial observations. On this basis, a variant of the sparse identification of nonlinear dynamics (SINDy) algorithm is developed. First, the Akaike information criterion (AIC) is integrated to enforce model selection by hierarchically ranking the most informative model from several manageable candidate models. This integration avoids restricting the number of candidate models, which is a disadvantage of the traditional methods for model selection. The subsequent procedure expands the structure of dynamics from ordinary differential equations (ODEs) to partial differential equations (PDEs), while group sparsity is employed to identify the nonconstant coefficients of partial differential equations. Of practical consideration within an integrated frame is data processing, which tends to treat noise separate from signals and tends to parametrize the noise probability distribution. In particular, the coefficients of a species of canonical ODEs and PDEs, such as the Van der Pol, Rössler, Burgers' and Kuramoto-Sivashinsky equations, can be identified correctly with the introduction of noise. Furthermore, except for normal noise, the proposed approach is able to capture the distribution of uniform noise. In accordance with the results of the experiments, the computational speed is markedly advanced and possesses robustness.

9.
Anal Chem ; 94(5): 2453-2464, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-34978426

RESUMO

The drug toxicity is a long-term concern in contemporary medical research. Serious drug toxicity may cause acute liver failure or even patient death. Currently, the pathogenesis of drug-induced liver injury (DILI) is not entirely clear, and there is still no specific treatment for patients with DILI. Accordingly, improving the diagnosis and treatment level of DILI is a major challenge facing the basic and clinical research in relevant fields. To address these, an ·OH-activated circular dichroism (CD) and photoacoustic (PA) dual-mode nanoprobe was here designed and synthesized. The probe was prepared using chiral d/l-cysteine and polymolybdate as raw materials to form a nanocomplex with chiral properties (Ox-POM@d/l-Cys) based on the interaction between metal ions and sulfhydryl groups in Ox-POM@d/l-Cys. In vitro and in vivo experimental results have shown that the as-proposed dual-mode nanoprobe can be used not only for CD spectral detection of Fenton's reagent but also for PA imaging monitoring of ·OH. More importantly, inspired by the NIR PA properties, the Ox-POM@d/l-Cys probe was used for the first time to detect ·OH in DILI mice. This will provide very useful information for the diagnosis and treatment of DILI disease.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Radical Hidroxila , Animais , Dicroísmo Circular , Cisteína , Diagnóstico por Imagem , Humanos , Camundongos
10.
Anal Chem ; 94(41): 14143-14150, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36194526

RESUMO

Covalent-type probes or sensors have been seldom reported for aggregated proteins. Herein, we reported a series of covalent solvatochromic probes to selectively modify and detect aggregated proteomes through the Schiff base reaction. Such covalent modification was discovered by serendipity using the P1 probe with an aldehyde functional group, exhibiting enhanced fluorescence intensity and unusually large blue shift upon protein aggregation. Supported by the biochemical and mass spectrometry results, we identified that this probe can modify the lysine residue of aggregated proteins selectively over folded ones via the Schiff base reaction. The generality of designing such a covalent-type probe was demonstrated in multiple probe scaffolds using different model proteins. Finally, we exploited the distinct solvatochromism of P1 after Schiff base linkage with aggregated proteins to visualize the distinct morphology of aggregated proteomes, as well as to quantify the polarity heterogeneity inside it. This work may intrigue the exploration of other chemical reaction types to covalently functionalize aggregated proteins that were difficult to analyze.


Assuntos
Proteoma , Bases de Schiff , Aldeídos , Lisina , Agregados Proteicos , Bases de Schiff/química
11.
Chembiochem ; 23(4): e202100443, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-34613660

RESUMO

Protein misfolding and aggregation is a complex biochemical process and has been associated with numerous human degenerative diseases. Developing novel chemical and biological tools and approaches to visualize aggregated proteins in live cells is in high demand for mechanistic studies, diagnostics, and therapeutics. In this review, we summarize the recent developments in the chemical biology toolbox applied to protein aggregation studies in live cells. These methods exploited fluorescent protein tags, fluorescent chemical tags, and small-molecule probes to visualize the protein-aggregation process, detect proteome stresses, and quantify the protein homeostasis network capacity. Inspired by these seminal works, we have generalized design principles for the development of new detection methods and probes in the future that will illuminate this important biological process.


Assuntos
Proteínas Luminescentes/metabolismo , Corantes Fluorescentes/química , Humanos , Proteínas Luminescentes/análise , Agregados Proteicos
12.
Eur J Neurol ; 29(1): 358-371, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34558762

RESUMO

BACKGROUND AND PURPOSE: The effect of mirror therapy for unilateral neglect after stroke currently remains uncertain. METHODS: This systematic review investigated the effect of mirror therapy on neglect and daily living activities in patients with unilateral neglect after stroke when compared with no treatment, sham mirror therapy, or routinely applied therapies only. We performed a systematic electronic search of PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, and Wanfang Data to identify relevant randomized control trials (RCTs). RESULTS: We included five RCTs in the data synthesis. Mirror therapy (combined or not with other treatments) was more effective in improving neglect as compared with sham mirror therapy or no treatment (combined or not with the other therapies; standard mean difference [SMD] = 1.62, 95% confidence interval [CI] = 1.03-2.21, p < 0.00001). Mirror therapy (combined or not with other therapies) was effective in improving daily living activities as compared with sham mirror therapy or no treatment (combined or not with the other therapies; SMD = 2.09, 95% CI = 0.63-3.56, p = 0.005). CONCLUSIONS: Our results show that mirror therapy effectively improves neglect and daily living activities in patients with unilateral neglect after stroke. Future trials with high methodological quality and larger sample sizes are needed to determine the immediate and long-term effect of appropriate mirror therapy protocol for unilateral neglect.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Atividades Cotidianas , China , Humanos , Terapia de Espelho de Movimento , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos
13.
Proc Natl Acad Sci U S A ; 116(40): 20104-20114, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527246

RESUMO

Viral cancers show oncogene addiction to viral oncoproteins, which are required for survival and proliferation of the dedifferentiated cancer cell. Human Merkel cell carcinomas (MCCs) that harbor a clonally integrated Merkel cell polyomavirus (MCV) genome have low mutation burden and require viral T antigen expression for tumor growth. Here, we showed that MCV+ MCC cells cocultured with keratinocytes undergo neuron-like differentiation with neurite outgrowth, secretory vesicle accumulation, and the generation of sodium-dependent action potentials, hallmarks of a neuronal cell lineage. Cocultured keratinocytes are essential for induction of the neuronal phenotype. Keratinocyte-conditioned medium was insufficient to induce this phenotype. Single-cell RNA sequencing revealed that T antigen knockdown inhibited cell cycle gene expression and reduced expression of key Merkel cell lineage/MCC marker genes, including HES6, SOX2, ATOH1, and KRT20 Of these, T antigen knockdown directly inhibited Sox2 and Atoh1 expression. MCV large T up-regulated Sox2 through its retinoblastoma protein-inhibition domain, which in turn activated Atoh1 expression. The knockdown of Sox2 in MCV+ MCCs mimicked T antigen knockdown by inducing MCC cell growth arrest and neuron-like differentiation. These results show Sox2-dependent conversion of an undifferentiated, aggressive cancer cell to a differentiated neuron-like phenotype and suggest that the ontology of MCC arises from a neuronal cell precursor.


Assuntos
Antígenos Virais de Tumores/genética , Carcinoma de Célula de Merkel/etiologia , Carcinoma de Célula de Merkel/metabolismo , Poliomavírus das Células de Merkel/genética , Fenótipo , Infecções por Polyomavirus/complicações , Fatores de Transcrição SOXB1/genética , Antígenos Virais de Tumores/imunologia , Antígenos Virais de Tumores/metabolismo , Carcinoma de Célula de Merkel/patologia , Ciclo Celular/genética , Linhagem Celular Tumoral , Linhagem da Célula/genética , Transformação Celular Viral , Técnicas de Silenciamento de Genes , Humanos , Queratinócitos , Células de Merkel/metabolismo , Poliomavírus das Células de Merkel/imunologia , Neuritos/metabolismo , Neurônios/metabolismo , Infecções por Polyomavirus/imunologia , Infecções por Polyomavirus/virologia , Fatores de Transcrição SOXB1/metabolismo , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/imunologia , Infecções Tumorais por Vírus/virologia
14.
Biochemistry ; 60(32): 2447-2456, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34369156

RESUMO

The turbidity assay is commonly exploited to study protein liquid-to-liquid phase separation (LLPS) or liquid-to-solid phase separation (LSPS) processes in biochemical analyses. Herein, we present common pitfalls of this assay caused by exceeding the detection linear range. We showed that aggregated proteins of high concentration and large particle size can lead to inaccurate quantification in multiple applications, including the optical density measurement, the thermal shift assay, and the dynamic light scattering experiment. Finally, we demonstrated that a simple sample dilution of insoluble aggregated protein (LSPS) samples or direct imaging of liquid droplets (LLPS) can address these issues and improve the accuracy of the turbidity assay.


Assuntos
Fracionamento Químico/métodos , Nefelometria e Turbidimetria/métodos , Proteínas/química , Proteínas/isolamento & purificação , Amiloide/análise , Amiloide/química , Difusão Dinâmica da Luz , Cinética , Limite de Detecção , Tamanho da Partícula , Agregados Proteicos , Análise Espectral
15.
Anal Chem ; 93(3): 1717-1724, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33382253

RESUMO

Stress-induced intracellular proteome aggregation is a hallmark and a biomarker of various human diseases. Current sensors requiring either cellular fixation or covalent modification of the entire proteome are not suitable for live-cell applications and dynamics study. Herein, we report a noncovalent, cell-permeable, and fluorogenic sensor that can reversibly bind to proteome amorphous aggregates and monitor their formation, transition, and clearance in live cells. This sensor was structurally optimized from previously reported fluorescent protein chromophores to enable noncovalent and reversible binding to aggregated proteins. Unlike all previous sensors, the noncovalent and reversible nature of this probe allows for dynamic detection of both the formation and clearance of aggregated proteome in one live-cell sample. Under different cellular stresses, this sensor reveals drastic differences in the morphology and location of aggregated proteome. Furthermore, we have shown that this sensor can detect the transition from proteome liquid-to-liquid phase separation to liquid-to-solid phase separation in a two-color imaging experiment. Overall, the sensor reported here can serve as a facile tool to screen therapeutic drugs and identify cellular pathways that ameliorate pathogenic proteome aggregation in live-cell models.


Assuntos
Corantes Fluorescentes/química , Proteoma/química , Técnicas Biossensoriais , Células HEK293 , Humanos , Estrutura Molecular , Imagem Óptica , Agregados Proteicos , Solubilidade , Espectrometria de Fluorescência
16.
Anal Chem ; 93(49): 16447-16455, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34859995

RESUMO

Common solvatochromic fluorophores exhibit a bathochromic fluorescence emission wavelength shift accompanied by intensity attenuation due to the presence of nonradiative decay pathways at the excited state. Such intrinsic but inevitable fluorescence quenching of solvatochromism impedes its applications to faithfully quantify local polarity, especially in a polar environment. Herein, we report a new donor-π-acceptor (D-π-A) type solvatochromic fluorophore scaffold containing a perfluorophenyl group that exhibits both a solvatochromic emission wavelength shift and a controllable emission intensity upon polarity fluctuation. The regulation of fluorescence solvatochromism and colors was achieved by tuning the aryl donors. We exploited such desired solvatochromism of these probes to monitor protein misfolding and aggregation via wavelength shift. Finally, the polarity of pathogenic aggregated proteins was quantified by HaloTag bioorthogonal labeling technology in live cells. While much effort has been devoted to resolving the morphology of pathogenic aggregated proteins, this work provides quantitative hints regarding the chemical information at this disease-related protein interphase.


Assuntos
Corantes Fluorescentes , Agregados Proteicos , Fluorescência , Ionóforos , Proteínas
17.
Chemistry ; 27(59): 14564-14576, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34342071

RESUMO

Protein phase separation process involving protein unfolding, misfolding, condensation and aggregation etc. has been associated with numerous human degenerative diseases. The complexity in protein conformational transitions results in multi-step and multi-species biochemical pathways upon protein phase separation. Recent progresses in designing novel fluorescent probes have unraveled the enriched details of phase separated proteins and provided mechanistic insights towards disease pathology. In this review, we summarized the design and characterizations of fluorescent probes that selectively illuminated proteins at different phase separated states with a focus on aggregation-induced emission probes, fluorescent molecular rotors, and solvatochromic fluorophores. Inspired by these pioneering works, a design blueprint was proposed to further develop fluorescent probes that can potentially shed light on the unresolved protein phase separated states in the future.


Assuntos
Corantes Fluorescentes , Proteínas , Humanos , Ionóforos
18.
Analyst ; 146(3): 835-841, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33325918

RESUMO

Survivin is widely expressed in tumor tissue, in which the in situ ratiometric fluorescence imaging of intracellular survivin mRNA can provide accurate information for the diagnosis and treatment of cancers, as well as the screening of antitumor drugs. However, the development of a nanoprobe that can be used simultaneously in the diagnosis and treatment of tumors and the screening of antitumor drugs remains a challenge. In an effort to address these requirements, a multifunctional biomass nanoprobe was developed for the photodynamic therapy (PDT) of tumors as well as cancer cell identification and antitumor drug screening based on the ratiometric fluorescence imaging of intracellular survivin mRNA. This nanoprobe was assembled from near-infrared (NIR) biomass quantum dots (BQDs), single-stranded DNA and NIR dye (dylight680) labeled single-stranded DNA. The BQDs contain a large number of chlorophyll molecules, meaning that they can produce a large amount of singlet oxygen under NIR light irradiation, thus realizing the PDT of a tumor. However, the specific binding of the nanoprobe to intracellular survivin mRNA causes the release of dylight680 and reduces the fluorescence resonance energy transfer (FRET) efficiency between the BQDs and dylight680 in the probe, thereby achieving the ratiometric fluorescence imaging of survivin mRNA. Therefore, the prepared nanoprobe can not only be used in the diagnosis of cancers, but also in the targeted PDT of tumors.


Assuntos
Antineoplásicos , Neoplasias , Fotoquimioterapia , Biomassa , DNA , Detecção Precoce de Câncer , Humanos , Imagem Óptica
19.
Neural Plast ; 2021: 1987662, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976049

RESUMO

Purpose: To compare the effectiveness of contralaterally controlled functional electrical stimulation (CCFES) versus neuromuscular electrical stimulation (NMES) on motor recovery of the upper limb in subacute stroke patients. Materials and Methods: Fifty patients within six months poststroke were randomly assigned to the CCFES group (n = 25) and the NMES group (n = 25). Both groups underwent routine rehabilitation plus 20-minute stimulation on wrist extensors per day, five days a week, for 3 weeks. Fugl-Meyer Assessment of upper extremity (FMA-UE), action research arm test (ARAT), Barthel Index (BI), and surface electromyography (sEMG) were assessed at baseline and end of intervention. Results: After a 3-week intervention, FMA-UE and BI increased in both groups (p < 0.05). ARAT increased significantly only in the CCFES group (p < 0.05). The changes of FMA-UE, ARAT, and BI in the CCFES group were not greater than those in the NMES group. The improvement in sEMG response of extensor carpi radialis by CCFES was greater than that by NMES (p = 0.026). The cocontraction ratio (CCR) of flexor carpi radialis did not decrease in both groups. Conclusions: CCFES improved upper limb motor function, but did not show better treatment effect than NMES. CCFES significantly enhanced the sEMG response of paretic extensor carpi radialis compared with NMES, but did not decrease the cocontraction of antagonist.


Assuntos
Terapia por Estimulação Elétrica/métodos , Força Muscular/fisiologia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Extremidade Superior/fisiopatologia , Adulto , Idoso , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
20.
Gen Physiol Biophys ; 40(4): 329-339, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34350837

RESUMO

In this study, we aimed to identify the specific microRNAs (miRNAs) that are involved in the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) from ovariectomized (OVX) mice, and to further explore the mechanism by which these miRNAs regulate osteogenic differentiation. Based on the existing studies, the expression of seven miRNAs in BMSCs from OVX mice was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The expression of miR-133a-3p and osteogenesis-related genes (runt-related transcription factor 2 (Runx2), Osterix, alkaline phosphatase (ALP), and osteopontin) in BMSCs treated with miR-133a-3p mimics or inhibitors was detected by qRT-PCR or Western blotting. Osteogenesis efficiency was determined using ALP and alizarin red staining. The effector-target relationship between miR-133a-3p and ankyrin repeat domain 44 (ANKRD44) was confirmed by bioinformatics and a dual luciferase assay. Among the seven selected miRNAs, miR-133a-3p expression was significantly increased in BMSCs from OVX mice. Overexpression of miR-133a-3p dramatically inhibited the expression of osteogenesis-related genes in BMSCs and reduced ALP activity and mineralization. However, these processes were markedly ameliorated upon miR-133a-3p inhibition. Moreover, miR-133a-3p appeared to target ANKRD44, and the ANKRD44 expression was negatively regulated by miR-133a- 3p. Furthermore, ANKRD44 upregulation eliminated the anti-osteogenic differentiation effects of miR-133a-3p in BMSCs. Thus, our results indicated that miR-133a-3p inhibits the osteogenic differentiation of BMSCs by suppressing ANKRD44.


Assuntos
Células-Tronco Mesenquimais , MicroRNAs , Animais , Repetição de Anquirina , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Camundongos , MicroRNAs/genética , Osteogênese/genética
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