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1.
bioRxiv ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38260395

RESUMO

Amyotrophic lateral sclerosis is the most common fatal motor neuron disease. Approximately 90% of ALS patients exhibit pathology of the master RNA regulator, Transactive Response DNA Binding protein (TDP-43). Despite the prevalence TDP-43 pathology in ALS motor neurons, recent findings suggest immune dysfunction is a determinant of disease progression in patients. Whether TDP-43 pathology elicits disease-modifying immune responses in ALS remains underexplored. In this study, we demonstrate that TDP-43 pathology is internalized by antigen presenting cells, causes vesicle rupture, and leads to innate and adaptive immune cell activation. Using a multiplex imaging platform, we observed interactions between innate and adaptive immune cells near TDP-43 pathological lesions in ALS brain. We used a mass cytometry-based whole-blood stimulation assay to provide evidence that ALS patient peripheral immune cells exhibit responses to TDP-43 aggregates. Taken together, this study provides a novel link between TDP-43 pathology and ALS immune dysfunction, and further highlights the translational and diagnostic implications of monitoring and manipulating the ALS immune response.

2.
Elife ; 122023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819053

RESUMO

TDP-43 proteinopathies including frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) are neurodegenerative disorders characterized by aggregation and mislocalization of the nucleic acid-binding protein TDP-43 and subsequent neuronal dysfunction. Here, we developed endogenous models of sporadic TDP-43 proteinopathy based on the principle that disease-associated TDP-43 acetylation at lysine 145 (K145) alters TDP-43 conformation, impairs RNA-binding capacity, and induces downstream mis-regulation of target genes. Expression of acetylation-mimic TDP-43K145Q resulted in stress-induced nuclear TDP-43 foci and loss of TDP-43 function in primary mouse and human-induced pluripotent stem cell (hiPSC)-derived cortical neurons. Mice harboring the TDP-43K145Q mutation recapitulated key hallmarks of FTLD, including progressive TDP-43 phosphorylation and insolubility, TDP-43 mis-localization, transcriptomic and splicing alterations, and cognitive dysfunction. Our study supports a model in which TDP-43 acetylation drives neuronal dysfunction and cognitive decline through aberrant splicing and transcription of critical genes that regulate synaptic plasticity and stress response signaling. The neurodegenerative cascade initiated by TDP-43 acetylation recapitulates many aspects of human FTLD and provides a new paradigm to further interrogate TDP-43 proteinopathies.


Assuntos
Esclerose Lateral Amiotrófica , Disfunção Cognitiva , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Proteinopatias TDP-43 , Humanos , Animais , Camundongos , Proteinopatias TDP-43/genética , Proteinopatias TDP-43/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/metabolismo , Esclerose Lateral Amiotrófica/genética , Demência Frontotemporal/genética , Modelos Animais de Doenças , RNA
3.
iScience ; 26(5): 106645, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37182104

RESUMO

Transactive response DNA-binding protein of 43 kDa (TDP-43) is a highly conserved, ubiquitously expressed nucleic acid-binding protein that regulates DNA/RNA metabolism. Genetics and neuropathology studies have linked TDP-43 to several neuromuscular and neurological disorders including amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Under pathological conditions, TDP-43 mislocalizes to the cytoplasm where it forms insoluble, hyper-phosphorylated aggregates during disease progression. Here, we optimized a scalable in vitro immuno-purification strategy referred to as tandem detergent-extraction and immunoprecipitation of proteinopathy (TDiP) to isolate TDP-43 aggregates that recapitulate those identified in postmortem ALS tissue. Moreover, we demonstrate that these purified aggregates can be utilized in biochemical, proteomics, and live-cell assays. This platform offers a rapid, accessible, and streamlined approach to study ALS disease mechanisms, while overcoming many limitations that have hampered TDP-43 disease modeling and therapeutic drug discovery efforts.

4.
BMC Res Notes ; 12(1): 46, 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30665462

RESUMO

OBJECTIVE: The RNA exosome is an evolutionarily conserved 3'-5' exoribonucleolytic protein complex involved in processing and degradation of different classes of nuclear and cytoplasmic RNAs, and, therefore, important for the posttranscriptional control of gene expression. Despite the extensive in vivo functional studies and the structural data on the RNA exosome, few studies have been performed on the localization and expression of exosome subunits during gametogenesis, process during which gene expression is largely controlled at the posttranscriptional level. RESULTS: We report the identification of exosome subunits in Lithobates catesbeianus and analysis of the differential subcellular localization of RNA exosome core and catalytic subunits in testis cells. In addition, we show seasonal differences in the expression levels of four exosome subunits in different organs. In addition to being part of the RNA exosome complex, its subunits might participate independently of the complex in the control of gene expression during seasonal variation in bullfrog tissues. These results may be relevant for other eukaryotic species.


Assuntos
Complexo Multienzimático de Ribonucleases do Exossomo/metabolismo , Rana catesbeiana/fisiologia , Fenômenos Reprodutivos Fisiológicos , Estações do Ano , Testículo/metabolismo , Animais , Masculino , Rana catesbeiana/metabolismo , Espermatogênese/fisiologia
5.
Chembiochem ; 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29700982

RESUMO

Aptameric sensors can bind molecular targets and produce output signals, a phenomenon that is used in bioassays. In some cases, it is important to distinguish between monomeric and oligomeric forms of a target. Here, we propose a strategy to convert a monomer/oligomer-nonselective sensor into an oligomer-selective sensor. We designed an aptazyme that produced a high fluorescent output in the presence of oligomeric α-synuclein (a molecular marker of Parkinson's disease) but not its monomeric form. The strategy is potentially useful in the design of point-of-care tests for the diagnosis of neurodegenerative diseases.

6.
Prog Neurobiol ; 154: 21-36, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28445713

RESUMO

Understanding regulation of α-synuclein has long been a central focus for Parkinson's disease (PD) researchers. Accumulation of this protein in the Lewy body or neurites, mutations in the coding region of the gene and strong association of α-synuclein encoding gene multiplication (duplication/triplication) with familial form of PD have indicated the importance of this molecule in pathogenesis of the disease. Several years of research identified many potential faulty pathways associated with accumulation of α-synuclein inside dopaminergic neurons and its transmission to neighboring ones. Concurrently, an appreciable body of research is growing to understand the epigenetic and genetic deregulation of α-synuclein that might contribute to the disease pathology. Completion of the ENCODE (Encyclopedia of DNA Elements) project and recent advancement made in the epigenetic and trans factor mediated regulation of each gene, has tremendously accelerated the need to carefully understand the epigenetic structure of the gene (SNCA) encoding α-synuclein protein in order to decipher the regulation and contribution of α-synuclein to the pathogenesis of PD. We have also analyzed the detailed epigenetic structure of this gene with knowledge from ENCODE database, which may open new avenues in α-synuclein research. Interestingly, we have found that the gene contains several transcriptionally activate histone modifications and associated potential transcription factor binding sites in the non-coding areas that strongly suggest alternative regulatory pathways. Altogether this review will provide interesting insight of α-synuclein gene regulation from epigenetic, genetic and post-transcriptional perspectives and their potential implication in the PD pathogenesis.


Assuntos
Regulação da Expressão Gênica/genética , Doença de Parkinson/genética , alfa-Sinucleína/genética , Animais , Epigênese Genética/genética , Humanos , alfa-Sinucleína/biossíntese
7.
Mol Brain ; 10(1): 6, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28173842

RESUMO

Deregulation of α-synuclein encoding gene (SNCA) is one of the important facets of Parkinson's disease (PD) research. DNA methylation status of SNCA-intron1 has been shown to regulate the α-synuclein expression. The present study is aimed at investigating whether methylation of SNCA-intron1 is associated with higher expression of α-synuclein in PD. We have investigated the intron1 methylation status from 16 post-mortem brain samples comprised of 8 PD and 8 control subjects using bisulfite sequencing. We further correlated this methylation status with α-synuclein protein levels in substantia nigra of that individual using western blot analysis. We did not observe any significant difference in methylation of SNCA-intron1 region between PD and control samples. Moreover, no correlation was observed between methylation of SNCA-intron1 with α-synuclein level. Methylation of SNCA-intron1 region does not correlate with α-synuclein expression in PD samples.


Assuntos
Metilação de DNA/genética , Íntrons/genética , Doença de Parkinson/genética , alfa-Sinucleína/genética , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade
8.
J Wound Care ; 22(10): 525-6, 528-33, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24142074

RESUMO

OBJECTIVE: To investigate the effectiveness of an innovative electrical stimulation (ES) therapy as adjuvant treatment for chronic wounds of various aetiology, in terms of pain and ulcer healing. METHOD: Patients with chronic limb ulcers were enrolled for the study and randomised into the intervention or control group. The intervention group received conventional treatment plus ES therapy (FREMS; Lorenz Lifetech) while the control group received only conventional treatment. Each ES treatment cycle consisted of 12 sessions performed in 4 weeks (three sessions/week). All patients were treated until full wound healing occurred, or for a maximum of 9 ES cycles, with a 2-week rest between each cycle. RESULTS: A total of 60 patients were enrolled in the study and randomised into the two groups: the intervention group (n=30) and the control group (n=30). During follow-up, some patients terminated the protocol because they reached the ulcer closure before the maximum of 9 cycles. The analysis of the effect of ES on pain and ulcer healing was performed on all patients who underwent at least two consecutive clinical evaluations (two cycles), in order to reach a compatible sample size with the primary objective (one patient withdrew). In both groups, there was a significant reduction of pain compared with baseline (p < 0.05), starting from T6 visit in the first cycle. In particular, there was a significant reduction of pain in the intervention group compared with the control group after 14 days, and this reduction continued until the end of the second cycle. Similarly, there was a significant reduction of PUSH tool score in the intervention group compared with the control group after 14 days, and this reduction continued until the end of the second cycle. CONCLUSION: Data collected in this study support data in the literature. Analysis of longitudinal data analysed by simple models and complex models suggest that the ES therapy had a positive and significant effect on pain reduction (VAS) and on the improvement of ulcer healing process in terms of the PUSH tool total index compared with conventional treatment, and may have induced a significant acceleration of the wound-healing process.


Assuntos
Úlcera da Perna , Úlcera Varicosa , Estimulação Elétrica , Humanos , Úlcera da Perna/terapia , Medição da Dor , Resultado do Tratamento , Úlcera Varicosa/terapia , Cicatrização
9.
Artigo em Inglês | MEDLINE | ID: mdl-24784967

RESUMO

Antibacterial drugs are used worldwide for the control of American and, less often, European foulbrood. Their administration is mostly uncontrolled and applied without approved protocols and instructions for use as well as precautionary recommendations. Consequently, this practice is responsible for the contamination of beehive products and contributes to the problem of food safety. According to this situation, 4672 analyses were carried out on 5303 honeys collected from 2001 to 2007. These samples were investigated for antibacterial residues of tetracyclines, sulphonamides, streptomycin, chloramphenicol and tylosin. Honeys were classified according to their origin: imported honey and honey from the Italian market. In the last group (only for samples collected from 2001 to 2004), another type of honey was distinguished: that of local honey. A total of 6.3% of all samples were positive for the antibacterial drugs analysed; in particular, 6.8% of imported honeys and 6.1% of honeys on the Italian market. Only 1.7% of local honey had antibacterial residues. These results are indicative of a rather frequent presence of antibacterial drug residues in both Italian and imported honeys. Furthermore, the data showed that among the active substances analysed, sulphonamides are the most used antibacterial substance followed by tetracyclines, streptomycin, tylosin, and chloramphenicol. Finally, a continuous monitoring programme is needed, accompanied by an education programme to beekeepers on proper hive management.


Assuntos
Antibacterianos/análise , Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Mel/análise , Animais , Antibacterianos/toxicidade , Criação de Abelhas , Abelhas , Cloranfenicol/análise , Cloranfenicol/toxicidade , Resíduos de Drogas/toxicidade , Análise de Alimentos/métodos , Mel/toxicidade , Humanos , Itália , Estreptomicina/análise , Estreptomicina/toxicidade , Sulfonamidas/análise , Sulfonamidas/toxicidade , Tetraciclinas/análise , Tetraciclinas/toxicidade , Tilosina/análise , Tilosina/toxicidade
10.
Ultrasound Obstet Gynecol ; 22(6): 643-5, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14689540

RESUMO

Congenital genu recurvatum (CGR) is an extremely rare condition observed at birth. It is associated with, among other malformations, genetic entities such as the Larsen syndrome. When CGR is isolated, orthopedic treatment will usually lead to a good functional prognosis. We report the first case of isolated CGR diagnosed prenatally and suspected to be a consequence of reduced amniotic fluid volume due to leakage following amniocentesis. The etiology and management options for CGR are briefly discussed.


Assuntos
Amniocentese/efeitos adversos , Articulação do Joelho/anormalidades , Ultrassonografia Pré-Natal , Adulto , Feminino , Humanos , Recém-Nascido , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/embriologia , Masculino , Gravidez
11.
Behav Processes ; 53(1-2): 137-143, 2001 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11255001

RESUMO

A dominance hierarchy based on the outcome of agonistic encounters was found among male and female domestic cats. A female dominated over some males. The dominance concept is also discussed in terms of social bonding. The relationships among adult females were amicable, whereas adult males showed reciprocal tolerance. The flow of affiliative behaviour was directed mainly from females to one male of the group. The analysis of marking behaviour showed that this male sprayed urine and rubbed the perioral and cheek regions of the face on the objects of the environment at a higher rate than the other members of the group. Nevertheless, rubbing the perioral and cheek regions of the face on objects was not correlated to dominance rank, possibly because it has some function in social communication other than territorial defence against strangers. No relationships have been found between claw scratching, rolling on the ground and social rank, or between the former and other marking behaviour. It is concluded that claw scratching and rolling were not utilised to mark territory.

12.
J Antimicrob Chemother ; 40(1): 19-25, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9249200

RESUMO

This paper reports the findings obtained using two new compounds belonging to the 5-nitroimidazole family: sulphuridazole (V1) and sulphonidazole (V2). We first assessed their antimicrobial activity on Clostridia spp. and then extended the study to Gram-positive and Gram-negative aerobic microorganisms and to Candida albicans. Their MICs were compared with those of metronidazole. The findings show that the antibacterial and antimycotic activity of sulphonidazole is greater than that of sulphuridazole, while metronidazole is not active against any aerobic organism. It also emerges that the NO2 group is indispensable for all the microorganisms assayed and that sulphuridazole and sulphonidazole are the first two 5-nitroimidazoles active against C. albicans. The redox potentials of the 5-nitroimidozoles studied suggest that their action mechanism is mainly based on redox processes.


Assuntos
Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Nitroimidazóis/farmacologia , Sulfonas/farmacologia , Antibacterianos , Candida/efeitos dos fármacos , Clostridium/efeitos dos fármacos , Eletroquímica/métodos , Escherichia coli/efeitos dos fármacos , Metronidazol/farmacologia , Testes de Sensibilidade Microbiana , Nitroimidazóis/química , Nitroimidazóis/metabolismo , Oxirredução
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