Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 178
Filtrar
1.
Nat Methods ; 20(3): 448-458, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36797410

RESUMO

Stimulated Raman scattering (SRS) offers the ability to image metabolic dynamics with high signal-to-noise ratio. However, its spatial resolution is limited by the numerical aperture of the imaging objective and the scattering cross-section of molecules. To achieve super-resolved SRS imaging, we developed a deconvolution algorithm, adaptive moment estimation (Adam) optimization-based pointillism deconvolution (A-PoD) and demonstrated a spatial resolution of lower than 59 nm on the membrane of a single lipid droplet (LD). We applied A-PoD to spatially correlated multiphoton fluorescence imaging and deuterium oxide (D2O)-probed SRS (DO-SRS) imaging from diverse samples to compare nanoscopic distributions of proteins and lipids in cells and subcellular organelles. We successfully differentiated newly synthesized lipids in LDs using A-PoD-coupled DO-SRS. The A-PoD-enhanced DO-SRS imaging method was also applied to reveal metabolic changes in brain samples from Drosophila on different diets. This new approach allows us to quantitatively measure the nanoscopic colocalization of biomolecules and metabolic dynamics in organelles.


Assuntos
Microscopia , Análise Espectral Raman , Microscopia/métodos , Análise Espectral Raman/métodos , Proteínas/metabolismo , Lipídeos
2.
Neurobiol Dis ; 185: 106245, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37527763

RESUMO

TDP-43 dysfunction is a molecular hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). A major hypothesis of TDP-43 dysfunction in disease is the loss of normal nuclear function, resulting in impaired RNA regulation and the emergence of cryptic exons. Cryptic exons and differential exon usage are emerging as promising markers of lost TDP-43 function in addition to revealing biological pathways involved in neurodegeneration in ALS/FTD. In this brief report, we identified markers of TDP-43 loss of function by depleting TARDBP from post-mortem human brain pericytes, a manipulable in vitro primary human brain cell model, and identifying differential exon usage events with bulk RNA-sequencing analysis. We present these data in an interactive database (https://www.scotterlab.auckland.ac.nz/research-themes/tdp43-lof-db-v2/) together with seven other TDP-43-depletion datasets we meta-analysed previously, for user analysis of differential expression and splicing signatures. Differential exon usage events that were validated by qPCR were then compiled into a 'differential exon usage panel' with other well-established TDP-43 loss-of-function exon markers. This differential exon usage panel was investigated in ALS and control motor cortex tissue to verify whether, and to what extent, TDP-43 loss of function occurs in ALS. We find that profiles of TDP-43-regulated cryptic exons, changed exon usage and changed 3' UTR usage discriminate ALS brain tissue from controls, verifying that TDP-43 loss of function occurs in ALS. We propose that TDP-43-regulated splicing events that occur in brain tissue will have promise as predictors of disease.


Assuntos
Esclerose Lateral Amiotrófica , Proteínas de Ligação a DNA , Demência Frontotemporal , Humanos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Encéfalo/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Demência Frontotemporal/genética , RNA , Splicing de RNA
3.
Oncologist ; 28(12): e1152-e1159, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37555463

RESUMO

BACKGROUND: Eribulin, a halichondrin-class microtubule dynamics inhibitor, is a preferred treatment option for patients with advanced breast cancer who have been pretreated with an anthracycline and a taxane. Peripheral neuropathy (PN) is a common side effect of chemotherapies for breast cancer and other tumors. The Incidence and Resolution of Eribulin-Induced Peripheral Neuropathy (IRENE) noninterventional postauthorization safety study assessed the incidence and severity of PN in patients with breast cancer treated with eribulin. PATIENTS AND METHODS: IRENE is an ongoing observational, single-arm, prospective, multicenter, cohort study. Adult patients (≥18 years of age) with locally advanced or metastatic breast cancer and disease progression after 1-2 prior chemotherapeutic regimen(s) for advanced disease were treated with eribulin. Patients with eribulin-induced PN (new-onset PN or worsening of preexisting PN) were monitored until death or resolution of PN. Primary endpoints included the incidence, severity, and time to resolution of eribulin-induced PN. Secondary endpoints included time to disease progression and safety. RESULTS: In this interim analysis (data cutoff date: July 1, 2019), 67 (32.4%) patients experienced any grade eribulin-induced PN, and 12 (5.8%) patients experienced grade ≥3 eribulin-induced PN. Median time to resolution of eribulin-induced PN was not reached. Median time to disease progression was 4.6 months (95% CI, 4.0-6.5). Treatment-emergent adverse events (TEAEs) occurred in 195 (93.8%) patients and serious TEAEs occurred in 107 (51.4%) patients. CONCLUSION: The rates of any grade and grade ≥3 eribulin-induced PN observed in this real-world study were consistent with those observed in phase III randomized clinical trials. No new safety findings were observed.


Assuntos
Neoplasias da Mama , Doenças do Sistema Nervoso Periférico , Adulto , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Estudos de Coortes , Progressão da Doença , Furanos/efeitos adversos , Incidência , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/epidemiologia , Estudos Prospectivos , Resultado do Tratamento , Moduladores de Tubulina/efeitos adversos
4.
Bioinformatics ; 38(19): 4474-4480, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35946527

RESUMO

MOTIVATION: Alternative splicing is an important mechanism to generate transcriptomic and phenotypic diversity. Existing methods have limited power to detect orthologous isoforms. RESULTS: We develop a new method, EGIO, to detect orthologous exons and orthologous isoforms from two species. EGIO uses unique exonic regions to construct exon groups, in which process dynamic programming strategy is used to do exon alignment. EGIO could cover all the coding exons within orthologous genes. A comparison between EGIO and ExTraMapper shows that EGIO could detect more orthologous isoforms with conserved sequence and exon structures. We apply EGIO to compare human and chimpanzee protein-coding isoforms expressed in the frontal cortex and identify 6912 genes that express human unique isoforms. Unexpectedly, more human unique isoforms are detected than those conserved between humans and chimpanzees. AVAILABILITY AND IMPLEMENTATION: Source code and test data of EGIO are available at https://github.com/wu-lab-egio/EGIO. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Processamento Alternativo , Software , Humanos , Éxons , Isoformas de Proteínas/genética , Sequência Conservada
5.
EMBO Rep ; 22(7): e52006, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-34096155

RESUMO

Tunneling nanotubes (TNTs) are actin-rich structures that connect two or more cells and mediate cargo exchange between spatially separated cells. TNTs transport signaling molecules, vesicles, organelles, and even pathogens. However, the molecular mechanisms regulating TNT formation remain unclear and little is known about the endogenous mechanisms suppressing TNT formation in lung cancer cells. Here, we report that MICAL2PV, a splicing isoform of the neuronal guidance gene MICAL2, is a novel TNT regulator that suppresses TNT formation and modulates mitochondrial distribution. MICAL2PV interacts with mitochondrial Rho GTPase Miro2 and regulates subcellular mitochondrial trafficking. Moreover, down-regulation of MICAL2PV enhances survival of cells treated with chemotherapeutical drugs. The monooxygenase (MO) domain of MICAL2PV is required for its activity to inhibit TNT formation by depolymerizing F-actin. Our data demonstrate a previously unrecognized function of MICAL2 in TNT formation and mitochondrial trafficking. Furthermore, our study uncovers a role of the MICAL2PV-Miro2 axis in mitochondrial trafficking, providing a mechanistic explanation for MICAL2PV activity in suppressing TNT formation and in modulating mitochondrial subcellular distribution.


Assuntos
Comunicação Celular , Nanotubos , Citoesqueleto de Actina , Actinas/genética , Humanos , Proteínas dos Microfilamentos , Organelas , Oxirredutases
6.
Mol Cell Neurosci ; 123: 103768, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36038081

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal movement disorder involving degeneration of motor neurons through dysfunction of the RNA-binding protein TDP-43. Pericytes, the perivascular cells of the blood-brain, blood-spinal cord, and blood-CSF barriers also degenerate in ALS. Indeed, pericytes are among the earliest cell types to show gene expression changes in pre-symptomatic animal models of ALS. This suggests that pericyte degeneration precedes neurodegeneration and may involve pericyte cell-autonomous TDP-43 dysfunction. Here we determined the effect of TDP-43 dysfunction in human brain pericytes on interleukin 6 (IL-6), a critical secreted inflammatory mediator reported to be regulated by TDP 43. Primary human brain pericytes were cultured from biopsy tissue from epilepsy surgeries and TDP-43 was silenced using siRNA. TDP-43 silencing of pericytes stimulated with pro-inflammatory cytokines, interleukin-1ß or tumour necrosis factor alpha, robustly suppressed the induction of IL-6 transcript and protein. IL-6 regulation by TDP-43 did not involve the assembly of TDP-43 nuclear splicing bodies, and did not occur via altered splicing of IL6. Instead, transcriptome-wide analysis by RNA-Sequencing identified a poison exon in the IL6 destabilising factor HNRNPD (AUF1) as a splicing target of TDP-43. Our data support a model whereby TDP-43 silencing favours destabilisation of IL6 mRNA, via enhanced AU-rich element-mediated decay by HNRNP/AUF1. This suggests that cell-autonomous deficits in TDP-43 function in human brain pericytes would suppress their production of IL-6. Given the importance of the blood-brain and blood-spinal cord barriers in maintaining motor neuron health, TDP-43 in human brain pericytes may represent a cellular target for ALS therapeutics.


Assuntos
Esclerose Lateral Amiotrófica , Proteínas de Ligação a DNA , Interleucina-6 , Pericitos , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Encéfalo/metabolismo , Citocinas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Expressão Gênica , Interleucina-6/metabolismo , Pericitos/metabolismo , Pericitos/patologia , Medula Espinal/metabolismo
7.
Development ; 146(3)2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30674481

RESUMO

A switch in the response of commissural axons to the repellent Slit is crucial for ensuring that they cross the ventral midline only once. However, the underlying mechanisms remain to be elucidated. We have found that both endocytosis and recycling of Robo1 receptor are crucial for modulating Slit sensitivity in vertebrate commissural axons. Robo1 endocytosis and its recycling back to the cell surface maintained the stability of axonal Robo1 during Slit stimulation. We identified Arf6 guanosine triphosphatase and its activators, cytohesins, as previously unknown components in Slit-Robo1 signalling in vertebrate commissural neurons. Slit-Robo1 signalling activated Arf6. The Arf6-deficient mice exhibited marked defects in commissural axon midline crossing. Our data showed that a Robo1 endocytosis-triggered and Arf6-mediated positive-feedback strengthens the Slit response in commissural axons upon their midline crossing. Furthermore, the cytohesin-Arf6 pathways modulated this self-enhancement of the Slit response before and after midline crossing, resulting in a switch that reinforced robust regulation of axon midline crossing. Our study provides insights into endocytic trafficking-mediated mechanisms for spatiotemporally controlled axonal responses and uncovers new players in the midline switch in Slit responsiveness of commissural axons.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Axônios/metabolismo , Endocitose/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Transdução de Sinais/fisiologia , Fator 6 de Ribosilação do ADP , Fatores de Ribosilação do ADP/genética , Animais , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Proteínas Roundabout
8.
PLoS Genet ; 15(5): e1007947, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31100073

RESUMO

Mutations in or dys-regulation of the TDP-43 gene have been associated with TDP-43 proteinopathy, a spectrum of neurodegenerative diseases including Frontotemporal Lobar Degeneration (FTLD) and Amyotrophic Lateral Sclerosis (ALS). The underlying molecular and cellular defects, however, remain unclear. Here, we report a systematic study combining analyses of patient brain samples with cellular and animal models for TDP-43 proteinopathy. Electron microscopy (EM) analyses of patient samples revealed prominent mitochondrial impairment, including abnormal cristae and a loss of cristae; these ultrastructural changes were consistently observed in both cellular and animal models of TDP-43 proteinopathy. In these models, increased TDP-43 expression induced mitochondrial dysfunction, including decreased mitochondrial membrane potential and elevated production of reactive oxygen species (ROS). TDP-43 expression suppressed mitochondrial complex I activity and reduced mitochondrial ATP synthesis. Importantly, TDP-43 activated the mitochondrial unfolded protein response (UPRmt) in both cellular and animal models. Down-regulating mitochondrial protease LonP1 increased mitochondrial TDP-43 levels and exacerbated TDP-43-induced mitochondrial damage as well as neurodegeneration. Together, our results demonstrate that TDP-43 induced mitochondrial impairment is a critical aspect in TDP-43 proteinopathy. Our work has not only uncovered a previously unknown role of LonP1 in regulating mitochondrial TDP-43 levels, but also advanced our understanding of the pathogenic mechanisms for TDP-43 proteinopathy. Our study suggests that blocking or reversing mitochondrial damage may provide a potential therapeutic approach to these devastating diseases.


Assuntos
Proteases Dependentes de ATP/genética , Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Degeneração Lobar Frontotemporal/genética , Proteínas Mitocondriais/genética , Proteinopatias TDP-43/genética , Resposta a Proteínas não Dobradas , Proteases Dependentes de ATP/metabolismo , Trifosfato de Adenosina/biossíntese , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Drosophila melanogaster , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Degeneração Lobar Frontotemporal/metabolismo , Degeneração Lobar Frontotemporal/patologia , Regulação da Expressão Gênica , Células HEK293 , Humanos , Potencial da Membrana Mitocondrial/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Mutação , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteinopatias TDP-43/metabolismo , Proteinopatias TDP-43/patologia
9.
Lancet Oncol ; 22(7): 946-958, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34143969

RESUMO

BACKGROUND: Despite advances in the first-line treatment of metastatic renal cell carcinoma (RCC), there is an unmet need for options to address disease progression during or after treatment with immune checkpoint inhibitors (ICIs). Pembrolizumab and lenvatinib are active as monotherapies in RCC; thus, we aimed to evaluate the combination of lenvatinib plus pembrolizumab in these patients. METHODS: We report results of the metastatic RCC cohort from an open-label phase 1b/2 study of lenvatinib plus pembrolizumab in patients aged at least 18 years with selected solid tumours and an Eastern Cooperative Oncology Group performance status of 0-1. Oral lenvatinib at 20 mg was given once daily along with intravenous pembrolizumab at 200 mg once every 3 weeks. Patients remained on study drug treatment until disease progression, development of unacceptable toxicity, or withdrawal of consent. Efficacy was analysed in patients with clear cell metastatic RCC receiving study drug by previous therapy grouping: treatment naive, previously treated ICI naive (previously treated with at least one line of therapy but not with an anti-PD-1 or anti-PD-L1 ICI), and ICI pretreated (ie, anti-PD-1 or anti-PD-L1) patients. Safety was analysed in all enrolled and treated patients. The primary endpoint was the objective response rate at week 24 per immune-related Response Evaluation Criteria In Solid Tumors (irRECIST) by investigator assessment. This trial is registered with ClinicalTrials.gov (NCT02501096) and with the EU Clinical Trials Register (EudraCT2017-000300-26), and is closed to new participants. FINDINGS: Between July 21, 2015, and Oct 16, 2019, 145 patients were enrolled in the study. Two patients had non-clear cell RCC and were excluded from the efficacy analysis (one in the treatment-naive group and one in the ICI-pretreated group); thus, the population evaluated for efficacy comprised 143 patients (n=22 in the treatment-naive group, n=17 in the previously treated ICI-naive group, and n=104 in the ICI-pretreated group). All 145 enrolled patients were included in the safety analysis. The median follow-up was 19·8 months (IQR 14·3-28·4). The number of patients with an objective response at week 24 by irRECIST was 16 (72·7%, 95% CI 49·8-89·3) of 22 treatment-naive patients, seven (41·2%, 18·4-67·1) of 17 previously treated ICI-naive patients, and 58 (55·8%, 45·7-65·5) of 104 ICI-pretreated patients. Of 145 patients, 82 (57%) had grade 3 treatment-related adverse events and ten (7%) had grade 4 treatment-related adverse events. The most common grade 3 treatment-related adverse event was hypertension (30 [21%] of 145 patients). Treatment-related serious adverse events occurred in 36 (25%) patients, and there were three treatment-related deaths (upper gastrointestinal haemorrhage, sudden death, and pneumonia). INTERPRETATION: Lenvatinib plus pembrolizumab showed encouraging antitumour activity and a manageable safety profile and might be an option for post-ICI treatment of metastatic RCC. FUNDING: Eisai and Merck Sharp & Dohme.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinolinas/uso terapêutico , Idoso , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/secundário , Europa (Continente) , Feminino , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Quinolinas/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
10.
Proc Natl Acad Sci U S A ; 115(41): E9678-E9686, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30249657

RESUMO

FUS (fused in sarcoma) proteinopathy is a group of neurodegenerative diseases characterized by the formation of inclusion bodies containing the FUS protein, including frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Previous studies show that mitochondrial damage is an important aspect of FUS proteinopathy. However, the molecular mechanisms by which FUS induces mitochondrial damage remain to be elucidated. Our biochemical and genetic experiments demonstrate that FUS interacts with the catalytic subunit of mitochondrial ATP synthase (ATP5B), disrupts the formation of ATP synthase complexes, and inhibits mitochondrial ATP synthesis. FUS expression activates the mitochondrial unfolded protein response (UPRmt). Importantly, down-regulating expression of ATP5B or UPRmt genes in FUS transgenic flies ameliorates neurodegenerative phenotypes. Our data show that mitochondrial impairment is a critical early event in FUS proteinopathy, and provide insights into the pathogenic mechanism of FUS-induced neurodegeneration.


Assuntos
Proteínas de Drosophila/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/metabolismo , Mitocôndrias/metabolismo , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Doenças Neurodegenerativas/metabolismo , Resposta a Proteínas não Dobradas , Animais , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/genética , Mitocôndrias/patologia , ATPases Mitocondriais Próton-Translocadoras/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia
11.
Chin J Physiol ; 64(1): 32-42, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33642342

RESUMO

This study was designed to evaluate the anti-inflammatory effects of Alpinia officinarum Hance extract (AOE) and identify its main active ingredients. AOE was obtained using a 95% ethanol extraction method. Lipopolysaccharide (LPS) were used to induce an inflammatory response in RAW264.7 cells. The results showed that AOE exerts anti-inflammatory effects via inhibition of prostaglandin E2 secretion and cyclooxygenase -2 (COX-2) production. We further analyzed the components of AOE using high-performance liquid chromatography and found that AOE is comprised of several bioactive flavonoids including quercetin (Q), kaempferol (K), galangin (G), and curcumin (C). These four flavonoids effectively inhibited nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α production. Moreover, they reduced COX-2 and inducible NO synthase expressions via regulation of nuclear factor kappa-light-chain-enhancer of activated B cells and c-Jun N-terminal kinase signaling pathways. Furthermore, we compared and contrasted the anti-inflammatory effects and mechanisms of these four flavonoids at the same dose in the LPS-induced cell inflammation model. The results showed that C is the most effective inhibitor of LPS-induced NO production. However, only Q and K effectively attenuated LPS-induced extracellular signal-regulated kinase and p38 elevations. In conclusion, AOE and its major bioactive compounds exert anti-inflammatory effects on LPS-induced inflammation. As A. officinarum Hance is much cheaper than any of its four flavonoids, especially G, we suggest using AOE as an anti-inflammatory agent.


Assuntos
Alpinia , NF-kappa B , Alpinia/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2 , Lipopolissacarídeos , Macrófagos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico , Óxido Nítrico Sintase Tipo II
12.
Hum Mol Genet ; 27(8): 1366-1381, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29432563

RESUMO

Traumatic brain injury (TBI) has been predicted to be a predisposing factor for amyotrophic lateral sclerosis (ALS) and other neurological disorders. Despite the importance of TBI in ALS progression, the underlying cellular and molecular mechanisms are still an enigma. Here, we examined the contribution of TBI as an extrinsic factor and investigated whether TBI influences the susceptibility of developing neurodegenerative symptoms. To evaluate the effects of TBI in vivo, we applied mild to severe trauma to Drosophila and found that TBI leads to the induction of stress granules (SGs) in the brain. The degree of SGs induction directly correlates with the level of trauma. Furthermore, we observed that the level of mortality is directly proportional to the number of traumatic hits. Interestingly, trauma-induced SGs are ubiquitin, p62 and TDP-43 positive, and persistently remain over time suggesting that SGs might be aggregates and exert toxicity in our fly models. Intriguingly, TBI on animals expressing ALS-linked genes increased mortality and locomotion dysfunction suggesting that mild trauma might aggravate neurodegenerative symptoms associated with ALS. Furthermore, we found elevated levels of high molecular weight ubiquitinated proteins and p62 in animals expressing ALS-causing genes with TBI, suggesting that TBI may lead to the defects in protein degradation pathways. Finally, we observed that genetic and pharmacological induction of autophagy enhanced the clearance of SGs and promoted survival of flies in vivo. Together, our study demonstrates that trauma can induce SG formation in vivo and might enhance neurodegenerative phenotypes in the fly models of ALS.


Assuntos
Esclerose Lateral Amiotrófica/genética , Lesões Encefálicas Traumáticas/genética , Encéfalo/metabolismo , Grânulos Citoplasmáticos/metabolismo , Drosophila melanogaster/genética , Demência Frontotemporal/genética , Processamento de Proteína Pós-Traducional , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Autofagia/genética , Encéfalo/patologia , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Grânulos Citoplasmáticos/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Humanos , Locomoção/fisiologia , Longevidade , Neurônios/metabolismo , Neurônios/patologia , Fatores Associados à Proteína de Ligação a TATA/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Fator de Transcrição TFIID/genética , Fator de Transcrição TFIID/metabolismo , Índices de Gravidade do Trauma , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinação
13.
Hum Mol Genet ; 25(23): 5059-5068, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27794540

RESUMO

Dysregulation of Fused in Sarcoma (FUS) gene expression is associated with fronto-temporal lobar degeneration (FTLD), and missense mutations in the FUS gene have been identified in patients affected by amyotrophic lateral sclerosis (ALS). However, molecular and cellular defects underlying FUS proteinopathy remain to be elucidated. Here, we examined whether genes important for mitochondrial quality control play a role in FUS proteinopathy. In our genetic screening, Pink1 and Park genes were identified as modifiers of neurodegeneration phenotypes induced by wild type (Wt) or ALS-associated P525L-mutant human FUS. Down-regulating expression of either Pink1 or Parkin genes ameliorated FUS-induced neurodegeneration phenotypes. The protein levels of PINK1 and Parkin were elevated in cells overexpressing FUS. Remarkably, ubiquitinylation of Miro1 protein, a downstream target of the E3 ligase activity of Parkin, was also increased in cells overexpressing FUS protein. In fly motor neurons expressing FUS, both motility and processivity of mitochondrial axonal transport were reduced by expression of either Wt- or P525L-mutant FUS. Finally, down-regulating PINK1 or Parkin partially rescued the locomotive defects and enhanced the survival rate in transgenic flies expressing FUS. Our data indicate that PINK1 and Parkin play an important role in FUS-induced neurodegeneration. This study has uncovered a previously unknown link between FUS proteinopathy and PINK1/Parkin genes, providing new insights into the pathogenesis of FUS proteinopathy.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Drosophila/genética , Degeneração Lobar Frontotemporal/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/genética , Degeneração Neural/genética , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Animais Geneticamente Modificados , Transporte Axonal/genética , Modelos Animais de Doenças , Degeneração Lobar Frontotemporal/fisiopatologia , Regulação da Expressão Gênica , Genes Modificadores/genética , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Mutação de Sentido Incorreto , Degeneração Neural/patologia , Fenótipo , Proteínas rho de Ligação ao GTP/genética
14.
Opt Express ; 26(11): 14375-14391, 2018 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-29877477

RESUMO

Conventional deconvolution methods assume that the microscopy system is spatially invariant, introducing considerable errors. We developed a method to more precisely estimate space-variant point-spread functions from sparse measurements. To this end, a space-variant version of deblurring algorithm was developed and combined with a total-variation regularization. Validation with both simulation and real data showed that our PSF model is more accurate than the piecewise-invariant model and the blending model. Comparing with the orthogonal basis decomposition based PSF model, our proposed model also performed with a considerable improvement. We also evaluated the proposed deblurring algorithm. Our new deblurring algorithm showed a significantly better signal-to-noise ratio and higher image quality than those of the conventional space-invariant algorithm.

15.
BMC Health Serv Res ; 18(1): 204, 2018 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-29566689

RESUMO

BACKGROUND: Population-based patterns of care studies are important for trauma care but conducting them is expensive and resource-intensive. Linkage of routinely collected administrative health data may provide an efficient alternative. The aims of this study are to describe the rehabilitation pathway for trauma survivors and to analyse the brain injury rehabilitation outcomes in the two care settings (specialist brain injury and non-specialist general rehabilitation units). METHODS: This is an observational study using routinely collected registry data (New South Wales Trauma Registry linked with the Australasian Rehabilitation Outcomes Centre Inpatient Dataset). The study cohort includes 268 road trauma patients who were admitted to trauma services between 2009 and 2012 and received inpatient rehabilitation because of a brain injury. RESULTS: Of those who need inpatient rehabilitation, 62% (n = 166) were admitted to specialist units with the remainder (n = 102) admitted to non-specialist units. Those admitted to a specialist units were younger (p < 0.001), had a lower cognitive FIM score (p = 0.003) on admission than those admitted to non-specialist units. Specialist units achieved better overall FIM score improvements from admission to discharge (43 vs 30 points, p > 0.001) but at a cost of longer length of stay (median 47 vs 24 days, p < 0.001). There were very few discharges to residential aged care facilities from rehabilitation (2% in non-specialist units and none from specialist units). There was a long time lag between trauma and admission to inpatient rehabilitation with only a quarter of the patients admitted to a specialist unit by end of week four. Few older patients (19%) with brain injury were admitted to specialist units. CONCLUSIONS: It is feasible to use routinely collected registry data to monitor inpatient rehabilitation outcomes of trauma care. There were differences in characteristics and outcomes of patients with traumatic brain injury admitted to specialist units compared with non-specialist units.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Lesões Encefálicas/etiologia , Lesões Encefálicas/reabilitação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Armazenamento e Recuperação da Informação , Masculino , Pessoa de Meia-Idade , New South Wales , Sistema de Registros , Resultado do Tratamento , Adulto Jovem
16.
PLoS Genet ; 11(9): e1005357, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26335776

RESUMO

FUS-proteinopathies, a group of heterogeneous disorders including ALS-FUS and FTLD-FUS, are characterized by the formation of inclusion bodies containing the nuclear protein FUS in the affected patients. However, the underlying molecular and cellular defects remain unclear. Here we provide evidence for mitochondrial localization of FUS and its induction of mitochondrial damage. Remarkably, FTLD-FUS brain samples show increased FUS expression and mitochondrial defects. Biochemical and genetic data demonstrate that FUS interacts with a mitochondrial chaperonin, HSP60, and that FUS translocation to mitochondria is, at least in part, mediated by HSP60. Down-regulating HSP60 reduces mitochondrially localized FUS and partially rescues mitochondrial defects and neurodegenerative phenotypes caused by FUS expression in transgenic flies. This is the first report of direct mitochondrial targeting by a nuclear protein associated with neurodegeneration, suggesting that mitochondrial impairment may represent a critical event in different forms of FUS-proteinopathies and a common pathological feature for both ALS-FUS and FTLD-FUS. Our study offers a potential explanation for the highly heterogeneous nature and complex genetic presentation of different forms of FUS-proteinopathies. Our data also suggest that mitochondrial damage may be a target in future development of diagnostic and therapeutic tools for FUS-proteinopathies, a group of devastating neurodegenerative diseases.


Assuntos
Chaperonina 60/metabolismo , Proteínas de Drosophila/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Drosophila , Proteínas de Drosophila/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo F-H/genética , Mitocôndrias/metabolismo , Neurônios/metabolismo , Fenótipo , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo
17.
Clin Rehabil ; 31(9): 1189-1200, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28786337

RESUMO

OBJECTIVE: To investigate the impact of an in-reach rehabilitation team for patients admitted after road trauma. DESIGN: Randomised control trial of usual care versus early involvement of in-reach rehabilitation team. Telephone follow-up was conducted by a blind assessor at three months for those with minor/moderate injuries and six months for serious/severe injuries. SETTING: Four participating trauma services in New South Wales, Australia. SUBJECTS: A total of 214 patients admitted during 2012-2015 with a length of stay of at least five days. INTERVENTION: Provision of rehabilitation services in parallel with ward based therapy using an in-reach team for the intervention group. The control group could still access the ward based therapy (usual care). MAIN MEASURES: The primary outcome was acute length of stay. Secondary outcomes included percentage requiring inpatient rehabilitation, function (Functional Independence Measure and Timed Up and Go Test), psychological status (Depression Anxiety and Stress Score 21), pain (Orebro Musculoskeletal Pain Questionnaire) and quality of life (Short Form-12 v2). RESULTS: Median length of stay in acute care was 13 days (IQR 8-21). The intervention group, compared to the control group, received more physiotherapy and occupational therapy sessions (median number of sessions 16.0 versus 11.5, P=0.003). However, acute length of stay did not differ between the intervention and control groups (median 15 vs 12 days, P=0.37). There were no significant differences observed in the secondary outcomes at hospital discharge and follow-up. CONCLUSION: No additional benefit was found from the routine use of acute rehabilitation teams for trauma patients over and above usual care.


Assuntos
Hospitalização , Equipe de Assistência ao Paciente , Ferimentos e Lesões/reabilitação , Acidentes de Trânsito , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Fatores de Tempo , Resultado do Tratamento , Ferimentos e Lesões/etiologia
18.
Hum Mol Genet ; 23(25): 6863-77, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25113748

RESUMO

TDP-43 proteinopathies are clinically and genetically heterogeneous diseases that had been considered distinct from classical amyloid diseases. Here, we provide evidence for the structural similarity between TDP-43 peptides and other amyloid proteins. Atomic force microscopy and electron microscopy examination of peptides spanning a previously defined amyloidogenic fragment revealed a minimal core region that forms amyloid fibrils similar to the TDP-43 fibrils detected in FTLD-TDP brain tissues. An ALS-mutant A315E amyloidogenic TDP-43 peptide is capable of cross-seeding other TDP-43 peptides and an amyloid-ß peptide. Sequential Nuclear Overhauser Effects and double-quantum-filtered correlation spectroscopy in nuclear magnetic resonance (NMR) analyses of the A315E-mutant TDP-43 peptide indicate that it adopts an anti-parallel ß conformation. When added to cell cultures, the amyloidogenic TDP-43 peptides induce TDP-43 redistribution from the nucleus to the cytoplasm. Neuronal cultures in compartmentalized microfluidic-chambers demonstrate that the TDP-43 peptides can be taken up by axons and induce axonotoxicity and neuronal death, thus recapitulating key neuropathological features of TDP-43 proteinopathies. Importantly, a single amino acid change in the amyloidogenic TDP-43 peptide that disrupts fibril formation also eliminates neurotoxicity, supporting that amyloidogenesis is critical for TDP-43 neurotoxicity.


Assuntos
Peptídeos beta-Amiloides/química , Córtex Cerebral/efeitos dos fármacos , Proteínas de Ligação a DNA/toxicidade , Neurônios/efeitos dos fármacos , Proteinopatias TDP-43/metabolismo , Sequência de Aminoácidos , Animais , Morte Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Proteínas de Ligação a DNA/síntese química , Proteínas de Ligação a DNA/química , Células HEK293 , Humanos , Técnicas Analíticas Microfluídicas , Dados de Sequência Molecular , Neurônios/metabolismo , Neurônios/patologia , Cultura Primária de Células , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Transporte Proteico/efeitos dos fármacos , Ratos , Proteinopatias TDP-43/patologia
19.
J Cutan Med Surg ; 20(5): 484-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27060010

RESUMO

Leprosy reactions are acute inflammatory episodes that occur in the setting of Mycobacterium leprae infection. Precipitants of reactions can be pharmacologic and nonpharmacologic. Both type 1 and type 2 reactions typically occur before and during leprosy treatment but may also occur after treatment has been completed. Reactions cause morbidity due to nerve damage, and prompt corticosteroid therapy is warranted to minimize nerve damage due to reactions.


Assuntos
Inflamação/tratamento farmacológico , Inflamação/microbiologia , Hanseníase/complicações , Humanos , Inflamação/complicações , Inflamação/diagnóstico , Hanseníase/imunologia , Doenças do Sistema Nervoso Periférico/etiologia
20.
Int J Cancer ; 136(8): 1792-802, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25242263

RESUMO

Originally discovered in neuronal guidance, the Slit-Robo pathway is emerging as an important player in human cancers. However, its involvement and mechanism in colorectal cancer (CRC) remains to be elucidated. Here, we report that Slit2 expression is reduced in CRC tissues compared with adjacent noncancerous tissues. Extensive promoter hypermethylation of the Slit2 gene has been observed in CRC cells, which provides a mechanistic explanation for the Slit2 downregulation in CRC. Functional studies showed that Slit2 inhibits CRC cell migration in a Robo-dependent manner. Robo-interacting ubiquitin-specific protease 33 (USP33) is required for the inhibitory function of Slit2 on CRC cell migration by deubiquitinating and stabilizing Robo1. USP33 expression is downregulated in CRC samples, and reduced USP33 mRNA levels are correlated with increased tumor grade, lymph node metastasis and poor patient survival. Taken together, our data reveal USP33 as a previously unknown tumor-suppressing gene for CRC by mediating the inhibitory function of Slit-Robo signaling on CRC cell migration. Our work suggests the potential value of USP33 as an independent prognostic marker of CRC.


Assuntos
Movimento Celular/genética , Neoplasias Colorretais/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Receptores Imunológicos/genética , Transdução de Sinais/genética , Ubiquitina Tiolesterase/genética , Células CACO-2 , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Regulação para Baixo/genética , Genes Supressores de Tumor/fisiologia , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metástase Linfática/genética , Metástase Linfática/patologia , Proteínas do Tecido Nervoso/metabolismo , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Receptores Imunológicos/metabolismo , Ubiquitina Tiolesterase/metabolismo , Proteínas Roundabout
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA