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1.
Nat Immunol ; 17(2): 140-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26657003

RESUMO

Innate sensing of pathogens initiates inflammatory cytokine responses that need to be tightly controlled. We found here that after engagement of Toll-like receptors (TLRs) in myeloid cells, deficient sumoylation caused increased secretion of transcription factor NF-κB-dependent inflammatory cytokines and a massive type I interferon signature. In mice, diminished sumoylation conferred susceptibility to endotoxin shock and resistance to viral infection. Overproduction of several NF-κB-dependent inflammatory cytokines required expression of the type I interferon receptor, which identified type I interferon as a central sumoylation-controlled hub for inflammation. Mechanistically, the small ubiquitin-like modifier SUMO operated from a distal enhancer of the gene encoding interferon-ß (Ifnb1) to silence both basal and stimulus-induced activity of the Ifnb1 promoter. Therefore, sumoylation restrained inflammation by silencing Ifnb1 expression and by strictly suppressing an unanticipated priming by type I interferons of the TLR-induced production of inflammatory cytokines.


Assuntos
Resistência à Doença , Regulação da Expressão Gênica , Imunidade Inata , Imunomodulação , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Sumoilação , Animais , Cromatina/genética , Cromatina/metabolismo , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Loci Gênicos , Inflamação/virologia , Mediadores da Inflamação/metabolismo , Interferon beta/metabolismo , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Ligação Proteica , Receptor de Interferon alfa e beta/metabolismo , Elementos Reguladores de Transcrição , Proteína SUMO-1/metabolismo , Choque Séptico/genética , Choque Séptico/imunologia , Choque Séptico/metabolismo , Transdução de Sinais , Sumoilação/genética , Sumoilação/imunologia , Receptores Toll-Like/metabolismo
2.
Bioessays ; 46(1): e2300098, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38018264

RESUMO

The evolution and biodiversity of ageing have long fascinated scientists and the public alike. While mammals, including long-lived species such as humans, show a marked ageing process, some species of reptiles and amphibians exhibit very slow and even the absence of ageing phenotypes. How can reptiles and other vertebrates age slower than mammals? Herein, I propose that evolving during the rule of the dinosaurs left a lasting legacy in mammals. For over 100 million years when dinosaurs were the dominant predators, mammals were generally small, nocturnal, and short-lived. My hypothesis is that such a long evolutionary pressure on early mammals for rapid reproduction led to the loss or inactivation of genes and pathways associated with long life. I call this the 'longevity bottleneck hypothesis', which is further supported by the absence in mammals of regenerative traits. Although mammals, such as humans, can evolve long lifespans, they do so under constraints dating to the dinosaur era.


Assuntos
Dinossauros , Longevidade , Animais , Envelhecimento/fisiologia , Dinossauros/fisiologia , Mamíferos/fisiologia , Répteis , Evolução Biológica
3.
Nucleic Acids Res ; 52(D1): D203-D212, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37811871

RESUMO

With recent progress in mapping N7-methylguanosine (m7G) RNA methylation sites, tens of thousands of experimentally validated m7G sites have been discovered in various species, shedding light on the significant role of m7G modification in regulating numerous biological processes including disease pathogenesis. An integrated resource that enables the sharing, annotation and customized analysis of m7G data will greatly facilitate m7G studies under various physiological contexts. We previously developed the m7GHub database to host mRNA m7G sites identified in the human transcriptome. Here, we present m7GHub v.2.0, an updated resource for a comprehensive collection of m7G modifications in various types of RNA across multiple species: an m7GDB database containing 430 898 putative m7G sites identified in 23 species, collected from both widely applied next-generation sequencing (NGS) and the emerging Oxford Nanopore direct RNA sequencing (ONT) techniques; an m7GDiseaseDB hosting 156 206 m7G-associated variants (involving addition or removal of an m7G site), including 3238 disease-relevant m7G-SNPs that may function through epitranscriptome disturbance; and two enhanced analysis modules to perform interactive analyses on the collections of m7G sites (m7GFinder) and functional variants (m7GSNPer). We expect that m7Ghub v.2.0 should serve as a valuable centralized resource for studying m7G modification. It is freely accessible at: www.rnamd.org/m7GHub2.


Assuntos
Bases de Dados de Ácidos Nucleicos , Sequenciamento de Nucleotídeos em Larga Escala , Processamento Pós-Transcricional do RNA , Humanos , Interpretação Estatística de Dados , Guanosina/genética
4.
Nucleic Acids Res ; 52(D1): D900-D908, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933854

RESUMO

Ageing is a complex and multifactorial process. For two decades, the Human Ageing Genomic Resources (HAGR) have aided researchers in the study of various aspects of ageing and its manipulation. Here, we present the key features and recent enhancements of these resources, focusing on its six main databases. One database, GenAge, focuses on genes related to ageing, featuring 307 genes linked to human ageing and 2205 genes associated with longevity and ageing in model organisms. AnAge focuses on ageing, longevity, and life-history across animal species, containing data on 4645 species. DrugAge includes information about 1097 longevity drugs and compounds in model organisms such as mice, rats, flies, worms and yeast. GenDR provides a list of 214 genes associated with the life-extending benefits of dietary restriction in model organisms. CellAge contains a catalogue of 866 genes associated with cellular senescence. The LongevityMap serves as a repository for genetic variants associated with human longevity, encompassing 3144 variants pertaining to 884 genes. Additionally, HAGR provides various tools as well as gene expression signatures of ageing, dietary restriction, and replicative senescence based on meta-analyses. Our databases are integrated, regularly updated, and manually curated by experts. HAGR is freely available online (https://genomics.senescence.info/).


Assuntos
Envelhecimento , Bases de Dados Genéticas , Genômica , Animais , Humanos , Envelhecimento/genética , Senescência Celular , Longevidade/genética
5.
Proc Natl Acad Sci U S A ; 120(52): e2306863120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38127978

RESUMO

The gut microbiota is a considerable source of biologically active compounds that can promote intestinal homeostasis and improve immune responses. Here, we used large expression libraries of cloned metagenomic DNA to identify compounds able to sustain an anti-inflammatory reaction on host cells. Starting with a screen for NF-κB activation, we have identified overlapping clones harbouring a heterodimeric ATP-binding cassette (ABC)-transporter from a Firmicutes. Extensive purification of the clone's supernatant demonstrates that the ABC-transporter allows for the efficient extracellular accumulation of three muropeptide precursor, with anti-inflammatory properties. They induce IL-10 secretion from human monocyte-derived dendritic cells and proved effective in reducing AIEC LF82 epithelial damage and IL-8 secretion in human intestinal resections. In addition, treatment with supernatants containing the muropeptide precursor reduces body weight loss and improves histological parameters in Dextran Sulfate Sodium (DSS)-treated mice. Until now, the source of peptidoglycan fragments was shown to come from the natural turnover of the peptidoglycan layer by endogenous peptidoglycan hydrolases. This is a report showing an ABC-transporter as a natural source of secreted muropeptide precursor and as an indirect player in epithelial barrier strengthening. The mechanism described here might represent an important component of the host immune homeostasis.


Assuntos
Colite , Microbioma Gastrointestinal , Humanos , Camundongos , Animais , Peptidoglicano/metabolismo , Intestinos/patologia , Inflamação/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Anti-Inflamatórios/metabolismo , Sulfato de Dextrana , Colite/metabolismo , Modelos Animais de Doenças , Colo/metabolismo , Camundongos Endogâmicos C57BL
6.
Trends Genet ; 38(3): 216-217, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34756472

RESUMO

A PubMed analysis shows that the vast majority of human genes have been studied in the context of cancer. As such, the study of nearly any human gene can be justified based on existing literature by its potential relevance to cancer. Moreover, these results have implications for analyzing and interpreting large-scale analyses.


Assuntos
Neoplasias , Humanos , Neoplasias/genética
7.
Nucleic Acids Res ; 51(D1): D145-D158, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454018

RESUMO

Gene co-expression analysis has emerged as a powerful method to provide insights into gene function and regulation. The rapid growth of publicly available RNA-sequencing (RNA-seq) data has created opportunities for researchers to employ this abundant data to help decipher the complexity and biology of genomes. Co-expression networks have proven effective for inferring the relationship between the genes, for gene prioritization and for assigning function to poorly annotated genes based on their co-expressed partners. To facilitate such analyses we created previously an online co-expression tool for humans and mice entitled GeneFriends. To continue providing a valuable tool to the scientific community, we have now updated the GeneFriends database and website. Here, we present the new version of GeneFriends, which includes gene and transcript co-expression networks based on RNA-seq data from 46 475 human and 34 322 mouse samples. The new database also encompasses tissue-specific gene co-expression networks for 20 human and 21 mouse tissues, dataset-specific gene co-expression maps based on TCGA and GTEx projects and gene co-expression networks for additional seven model organisms (fruit fly, zebrafish, worm, rat, yeast, cow and chicken). GeneFriends is freely available at http://www.genefriends.org/.


Assuntos
Bases de Dados Genéticas , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Animais , Humanos , RNA , Análise de Sequência de RNA
8.
Nucleic Acids Res ; 51(D1): D106-D116, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36382409

RESUMO

With advanced technologies to map RNA modifications, our understanding of them has been revolutionized, and they are seen to be far more widespread and important than previously thought. Current next-generation sequencing (NGS)-based modification profiling methods are blind to RNA modifications and thus require selective chemical treatment or antibody immunoprecipitation methods for particular modification types. They also face the problem of short read length, isoform ambiguities, biases and artifacts. Direct RNA sequencing (DRS) technologies, commercialized by Oxford Nanopore Technologies (ONT), enable the direct interrogation of any given modification present in individual transcripts and promise to address the limitations of previous NGS-based methods. Here, we present the first ONT-based database of quantitative RNA modification profiles, DirectRMDB, which includes 16 types of modification and a total of 904,712 modification sites in 25 species identified from 39 independent studies. In addition to standard functions adopted by existing databases, such as gene annotations and post-transcriptional association analysis, we provide a fresh view of RNA modifications, which enables exploration of the epitranscriptome in an isoform-specific manner. The DirectRMDB database is freely available at: http://www.rnamd.org/directRMDB/.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Processamento Pós-Transcricional do RNA , Análise de Sequência de RNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Anotação de Sequência Molecular , Isoformas de Proteínas , RNA/genética , Análise de Sequência de RNA/métodos , Bases de Dados de Ácidos Nucleicos
9.
Nucleic Acids Res ; 51(D1): D1388-D1396, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36062570

RESUMO

Recent advances in epitranscriptomics have unveiled functional associations between RNA modifications (RMs) and multiple human diseases, but distinguishing the functional or disease-related single nucleotide variants (SNVs) from the majority of 'silent' variants remains a major challenge. We previously developed the RMDisease database for unveiling the association between genetic variants and RMs concerning human disease pathogenesis. In this work, we present RMDisease v2.0, an updated database with expanded coverage. Using deep learning models and from 873 819 experimentally validated RM sites, we identified a total of 1 366 252 RM-associated variants that may affect (add or remove an RM site) 16 different types of RNA modifications (m6A, m5C, m1A, m5U, Ψ, m6Am, m7G, A-to-I, ac4C, Am, Cm, Um, Gm, hm5C, D and f5C) in 20 organisms (human, mouse, rat, zebrafish, maize, fruit fly, yeast, fission yeast, Arabidopsis, rice, chicken, goat, sheep, pig, cow, rhesus monkey, tomato, chimpanzee, green monkey and SARS-CoV-2). Among them, 14 749 disease- and 2441 trait-associated genetic variants may function via the perturbation of epitranscriptomic markers. RMDisease v2.0 should serve as a useful resource for studying the genetic drivers of phenotypes that lie within the epitranscriptome layer circuitry, and is freely accessible at: www.rnamd.org/rmdisease2.


Assuntos
Bases de Dados Factuais , Processamento Pós-Transcricional do RNA , Animais , Humanos , Fenótipo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Epigenômica
10.
Cell Mol Life Sci ; 80(6): 166, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37249642

RESUMO

Parkinson's disease (PD) is a multifactorial neurodegenerative disease characterized by the loss of dopaminergic neurons in the midbrain. In the prodromal phase several autonomic symptoms including orthostatic hypotension and constipation are correlated with increased α-synuclein pathology in peripheral tissues. It is currently accepted that some idiopathic PD cases may start in the gut (body-first PD) with accumulation of pathological α-synuclein in enteric neurons that may subsequently propagate caudo-rostrally to the central nervous system. In addition to the already-established regulation of synaptic vesicle trafficking, α-synuclein also seems to play a role in neuronal innate immunity after infection. Our goal was to understand if seeding the gut with the foodborne pathogen Listeria monocytogenes by oral gavage would impact gut immunity and eventually the central nervous system. Our results demonstrate that L. monocytogenes infection induced oligomerization of α-synuclein in the ileum, along with a pronounced pro-inflammatory local and systemic response that ultimately culminated in neuronal mitochondria dysfunction. We propose that, having evolved from ancestral endosymbiotic bacteria, mitochondria may be directly targeted by virulence factors of intracellular pathogens, and that mitochondrial dysfunction and fragmentation resulting also from the activation of the innate immune system at the gut level, trigger innate immune responses in midbrain neurons, which include α-synuclein oligomerization and neuroinflammation, all of which hallmarks of PD.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , alfa-Sinucleína , Doenças Neurodegenerativas/patologia , Mitocôndrias/patologia , Neurônios Dopaminérgicos/patologia
11.
Scand J Med Sci Sports ; 34(3): e14593, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38488439

RESUMO

BACKGROUND: Providing individual- and population-level data on children's physical fitness (PF) is a crucial public health and education priority. However, few national fitness monitoring or surveillance systems are currently in practice internationally. We aim to summarize the current European PF monitoring and surveillance systems for school-aged children and to provide experience-based guidelines on how to design such systems. METHODS: The FitBack network consists of experts from diverse backgrounds with the common interest to improve the accessibility of PF monitoring for young people globally. Through FitBack network, we identified and compared the national or regional PF monitoring and surveillance systems currently in operation across Europe. We formulated a 10-step approach for designing and establishing one's own system, based on analysis of experienced strengths, weaknesses, opportunities, and threats to monitoring childhood fitness. RESULTS: We identified a total of eight PF monitoring systems in Finland, France, Galicia of Spain, Hungary, Lithuania, Portugal, Serbia, and Slovenia. The FitBack network recommends the following steps for designing and establishing one's own system: (1) set up mission statements and aims, (2) involve stakeholders, (3) utilize scientific background, (4) governance structure, (5) ensure sufficient funding, (6) data management planning, (7) provide meaningful feedback, (8) conduct pilot testing, (9) plan implementation process, and (10) invest in communication with stakeholders. CONCLUSIONS: This study provides an updated overview of the best practices for school-aged children's fitness monitoring and surveillance in Europe. Additionally, it offers a 10-step approach to assist in the creation of similar systems in Europe or globally.


Assuntos
Exercício Físico , Instituições Acadêmicas , Criança , Humanos , Adolescente , Europa (Continente) , França , Aptidão Física
12.
Nucleic Acids Res ; 50(D1): D196-D203, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34986603

RESUMO

5-Methylcytosine (m5C) is one of the most prevalent covalent modifications on RNA. It is known to regulate a broad variety of RNA functions, including nuclear export, RNA stability and translation. Here, we present m5C-Atlas, a database for comprehensive collection and annotation of RNA 5-methylcytosine. The database contains 166 540 m5C sites in 13 species identified from 5 base-resolution epitranscriptome profiling technologies. Moreover, condition-specific methylation levels are quantified from 351 RNA bisulfite sequencing samples gathered from 22 different studies via an integrative pipeline. The database also presents several novel features, such as the evolutionary conservation of a m5C locus, its association with SNPs, and any relevance to RNA secondary structure. All m5C-atlas data are accessible through a user-friendly interface, in which the m5C epitranscriptomes can be freely explored, shared, and annotated with putative post-transcriptional mechanisms (e.g. RBP intermolecular interaction with RNA, microRNA interaction and splicing sites). Together, these resources offer unprecedented opportunities for exploring m5C epitranscriptomes. The m5C-Atlas database is freely accessible at https://www.xjtlu.edu.cn/biologicalsciences/m5c-atlas.


Assuntos
Bases de Dados Genéticas , Epigenoma/genética , Software , Transcriptoma/genética , 5-Metilcitosina/química , 5-Metilcitosina/metabolismo , Humanos , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Processamento Pós-Transcricional do RNA/genética , Análise de Sequência de RNA
13.
Nucleic Acids Res ; 50(18): 10290-10310, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36155798

RESUMO

As the most pervasive epigenetic mark present on mRNA and lncRNA, N6-methyladenosine (m6A) RNA methylation regulates all stages of RNA life in various biological processes and disease mechanisms. Computational methods for deciphering RNA modification have achieved great success in recent years; nevertheless, their potential remains underexploited. One reason for this is that existing models usually consider only the sequence of transcripts, ignoring the various regions (or geography) of transcripts such as 3'UTR and intron, where the epigenetic mark forms and functions. Here, we developed three simple yet powerful encoding schemes for transcripts to capture the submolecular geographic information of RNA, which is largely independent from sequences. We show that m6A prediction models based on geographic information alone can achieve comparable performances to classic sequence-based methods. Importantly, geographic information substantially enhances the accuracy of sequence-based models, enables isoform- and tissue-specific prediction of m6A sites, and improves m6A signal detection from direct RNA sequencing data. The geographic encoding schemes we developed have exhibited strong interpretability, and are applicable to not only m6A but also N1-methyladenosine (m1A), and can serve as a general and effective complement to the widely used sequence encoding schemes in deep learning applications concerning RNA transcripts.


Assuntos
Aprendizado Profundo , RNA Longo não Codificante , Regiões 3' não Traduzidas , Metilação , Isoformas de Proteínas/genética , RNA/genética , RNA/metabolismo , RNA Mensageiro/genética
14.
Eur J Appl Physiol ; 124(5): 1475-1486, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38117338

RESUMO

PURPOSE: We examined heart rate variability (HRV) and baroreflex sensitivity (BRS) disease- and age-related response at 10-and 60-min after an acute high-intensity interval (HIIE) and moderate continuous exercise (MICE) in older adults with and without type 2 diabetes mellitus (T2DM) and healthy young adults. METHODS: Twelve older male adults with (57-84 years) and without T2DM (57-76 years) and 12 healthy young male adults (20-40 years) completed an isocaloric acute bout of HIIE, MICE, and a non-exercise condition in a randomized order. Time and Wavelets-derived frequency domain indices of HRV and BRS were obtained in a supine position and offline over 2-min time-bins using Matlab. RESULTS: HIIE but not MICE reduced natural logarithm root mean square of successive differences (Ln-RMSSD) (d = - 0.85; 95% CI - 1.15 to - 0.55 ms, p < 0.001), Ln-high-frequency power (d = - 1.60; 95% CI - 2.24 to - 0.97 ms2; p < 0.001), and BRS (d = - 6.32; 95% CI - 9.35 to - 3.29 ms/mmHg, p < 0.001) in adults without T2DM (averaged over young and older adults without T2DM), returning to baseline 60 min into recovery. These indices remained unchanged in older adults with T2DM after HIIE and MICE. Older adults with T2DM had lower resting Ln-RMSSD and BRS than aged-matched controls (Ln-RMSSD, d = - 0.71, 95% CI - 1.16 to - 0.262 ms, p = 0.001; BRS d = - 3.83 ms/mmHg), 95% CI - 6.90 to - 0.76, p = 0.01). CONCLUSIONS: Cardiovagal modulation following acute aerobic exercise is intensity-dependent only in adults without T2DM, and appears age-independent. These findings provide evidence of cardiac autonomic impairments in older adults with T2DM at rest and following aerobic exercise.


Assuntos
Barorreflexo , Diabetes Mellitus Tipo 2 , Exercício Físico , Frequência Cardíaca , Humanos , Masculino , Diabetes Mellitus Tipo 2/fisiopatologia , Idoso , Pessoa de Meia-Idade , Frequência Cardíaca/fisiologia , Barorreflexo/fisiologia , Adulto , Exercício Físico/fisiologia , Idoso de 80 Anos ou mais , Nervo Vago/fisiologia , Nervo Vago/fisiopatologia , Envelhecimento/fisiologia , Adulto Jovem
15.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33574059

RESUMO

Ecological flexibility, extended lifespans, and large brains have long intrigued evolutionary biologists, and comparative genomics offers an efficient and effective tool for generating new insights into the evolution of such traits. Studies of capuchin monkeys are particularly well situated to shed light on the selective pressures and genetic underpinnings of local adaptation to diverse habitats, longevity, and brain development. Distributed widely across Central and South America, they are inventive and extractive foragers, known for their sensorimotor intelligence. Capuchins have among the largest relative brain size of any monkey and a lifespan that exceeds 50 y, despite their small (3 to 5 kg) body size. We assemble and annotate a de novo reference genome for Cebus imitator Through high-depth sequencing of DNA derived from blood, various tissues, and feces via fluorescence-activated cell sorting (fecalFACS) to isolate monkey epithelial cells, we compared genomes of capuchin populations from tropical dry forests and lowland rainforests and identified population divergence in genes involved in water balance, kidney function, and metabolism. Through a comparative genomics approach spanning a wide diversity of mammals, we identified genes under positive selection associated with longevity and brain development. Additionally, we provide a technological advancement in the use of noninvasive genomics for studies of free-ranging mammals. Our intra- and interspecific comparative study of capuchin genomics provides insights into processes underlying local adaptation to diverse and physiologically challenging environments, as well as the molecular basis of brain evolution and longevity.


Assuntos
Adaptação Fisiológica , Encéfalo/crescimento & desenvolvimento , Cebus/genética , Genoma , Longevidade/genética , Animais , Evolução Molecular , Citometria de Fluxo/métodos , Florestas , Genômica/métodos
16.
Int J Health Plann Manage ; 39(2): 220-228, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38124556

RESUMO

In this article we argue that the Member States of the European Union (EU) have consistently, since its inception, developed a shared framework to measure, monitor and intervene to improve the health status of its population, while invoking the subsidiarity principle for the health sector. As a result, a European Health Union (EHU) has been emerging insidiously and consistently, following the concept of a system for health. Using the World Health Organisation Building Blocks Framework, we analyse the normative and institutional developments related to EU citizens' health that have created a de facto EHU. Developments towards an EHU remain unequally distributed among the different building blocks analysed. The existing EHU is the result of a fragmented and incremental process, mostly grounded in governance, health intelligence and services' development. Health crisis, the Commission's agenda-setting activities and market pressures have been the most important push factors for these step-by-step processes.


Assuntos
Instalações de Saúde , União Europeia , Organização Mundial da Saúde
17.
Int J Mol Sci ; 25(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38542396

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder with an unknown cause. Recent research has highlighted the importance of the gut in neuronal and immune maturation through the exchange of nutrients and cellular signals. This has led to the "gut-first PD" hypothesis, which aims to explain many of the sporadic cases and their prodromal intestinal symptoms, such as constipation and intestinal α-synuclein (aSyn) aggregation. The link between mitochondrial dysfunction and aSyn deposition is central to PD pathophysiology, since they can also trigger pro-inflammatory signals associated with aSyn deposition, potentially contributing to the onset of PD. As mitochondria are derived from ancestral alpha-proteobacteria, other bacteria may specifically target this organelle. We sought to use Nocardia cyriacigeorgica, a bacterium previously associated with parkinsonism, and dextran sulfate sodium (DSS) as pro-inflammatory modulators to gain further insight into the onset of PD. This study indicates that aSyn aggregation plus mitochondrial dysfunction without intestinal barrier leakage are not sufficient to trigger gut-first PD.


Assuntos
Colite , Doenças Mitocondriais , Nocardia , Doença de Parkinson , Humanos , alfa-Sinucleína , Colite/induzido quimicamente , Neurônios
18.
Medicina (Kaunas) ; 60(1)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38256365

RESUMO

Introduction: Peroneal disorders are a common cause of ankle pain and lateral instability and have been described in as much as 77% of patients with lateral ankle instability. Clicking, swelling, pain, and tenderness in the peroneal tendons track are frequent symptoms, but they can be confused with other causes of lateral ankle pain. The management of peroneal disorders can be conservative or surgical. When the conservative treatment fails, surgery is indicated, and open or tendoscopic synovectomy, tubularization, tenodesis or tendon transfers can be performed. The authors present a surgical technique of tendoscopy associated to minimally invasive tenodesis for the treatment of peroneal tendon tears, as well as the preliminary results of patients submitted to this procedure. Methods: Four patients with chronic lateral ankle pain who were diagnosed with peroneal brevis pathology were treated between 2020 and 2022 with tendoscopic-assisted minimally invasive synovectomy and tenodesis. Using a 2.7 mm 30° arthroscope and a 3.0 mm shaver blade, the entire length of the peroneus brevis tendon and most parts of the peroneus longus tendon can be assessed within Sammarco's zones 1 and 2. After the inspection and synovectomy, a minimally invasive tenodesis is performed. Results: All patients were evaluated at least six months after surgery. All of them reported improvement in daily activities and in the Foot Function Index (FFI) questionnaire (pre-surgery mean FFI = 23.86%; post-surgery mean FFI = 6.15%), with no soft tissue complications or sural nerve complaints. Conclusion: The tendoscopy of the peroneal tendons allows the surgeon to assess their integrity, confirm the extent of the lesion, perform synovectomy, prepare the tendon for tenodesis, and perform it in a safe and minimally invasive way, reducing the risks inherent to the open procedure.


Assuntos
Dor Crônica , Procedimentos Ortopédicos , Tenodese , Humanos , Tendões/cirurgia , Perna (Membro) , Artralgia
19.
Gut ; 72(1): 73-89, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34836918

RESUMO

OBJECTIVE: Idiopathic Parkinson's disease (PD) is characterised by alpha-synuclein (aSyn) aggregation and death of dopaminergic neurons in the midbrain. Recent evidence posits that PD may initiate in the gut by microbes or their toxins that promote chronic gut inflammation that will ultimately impact the brain. In this work, we sought to demonstrate that the effects of the microbial toxin ß-N-methylamino-L-alanine (BMAA) in the gut may trigger some PD cases, which is especially worrying as this toxin is present in certain foods but not routinely monitored by public health authorities. DESIGN: To test the hypothesis, we treated wild-type mice, primary neuronal cultures, cell lines and isolated mitochondria with BMAA, and analysed its impact on gut microbiota composition, barrier permeability, inflammation and aSyn aggregation as well as in brain inflammation, dopaminergic neuronal loss and motor behaviour. To further examine the key role of mitochondria, we also determined the specific effects of BMAA on mitochondrial function and on inflammasome activation. RESULTS: BMAA induced extensive depletion of segmented filamentous bacteria (SFB) that regulate gut immunity, thus triggering gut dysbiosis, immune cell migration, increased intestinal inflammation, loss of barrier integrity and caudo-rostral progression of aSyn. Additionally, BMAA induced in vitro and in vivo mitochondrial dysfunction with cardiolipin exposure and consequent activation of neuronal innate immunity. These events primed neuroinflammation, dopaminergic neuronal loss and motor deficits. CONCLUSION: Taken together, our results demonstrate that chronic exposure to dietary BMAA can trigger a chain of events that recapitulate the evolution of the PD pathology from the gut to the brain, which is consistent with 'gut-first' PD.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Camundongos , Animais , Microbioma Gastrointestinal/fisiologia , Mesencéfalo/metabolismo , Mesencéfalo/patologia , Doença de Parkinson/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismo
20.
BMC Genomics ; 24(1): 644, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884865

RESUMO

INTRODUCTION: Understanding changes in cell identity in cancer and ageing is of great importance. In this work, we analyzed how gene expression changes in human tissues are associated with tissue specificity during cancer and ageing using transcriptome data from TCGA and GTEx. RESULTS: We found significant downregulation of tissue-specific genes during ageing in 40% of the tissues analyzed, which suggests loss of tissue identity with age. For most cancer types, we have noted a consistent pattern of downregulation in genes that are specific to the tissue from which the tumor originated. Moreover, we observed in cancer an activation of genes not usually expressed in the tissue of origin as well as an upregulation of genes specific to other tissues. These patterns in cancer were associated with patient survival. The age of the patient, however, did not influence these patterns. CONCLUSION: We identified loss of cellular identity in 40% of the tissues analysed during human ageing, and a clear pattern in cancer, where during tumorigenesis cells express genes specific to other organs while suppressing the expression of genes from their original tissue. The loss of cellular identity observed in cancer is associated with prognosis and is not influenced by age, suggesting that it is a crucial stage in carcinogenesis.


Assuntos
Neoplasias , Transcriptoma , Humanos , Envelhecimento/genética , Neoplasias/genética , Perfilação da Expressão Gênica , Carcinogênese/genética
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