Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
J Neurosci ; 42(49): 9263-9277, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36280265

RESUMO

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). In this study, we generated a transgenic model by crossing germline Parkin-/- mice with PolgAD257A mice, an established model of premature aging and mitochondrial stress. We hypothesized that loss of Parkin-/- in PolgAD257A/D257A mice would exacerbate mitochondrial dysfunction, leading to loss of dopamine neurons and nigral-striatal specific neurobehavioral motor dysfunction. We found that aged Parkin-/-/PolgAD257A/D257A male and female mice exhibited severe behavioral deficits, nonspecific to the nigral-striatal pathway, with neither dopaminergic neurodegeneration nor reductions in striatal dopamine. We saw no difference in expression levels of nuclear-encoded subunits of mitochondrial markers and mitochondrial Complex I and IV activities, although we did observe substantial reductions in mitochondrial-encoded COX41I, indicating mitochondrial dysfunction as a result of PolgAD257A/D257A mtDNA mutations. Expression levels of mitophagy markers LC3I/LC3II remained unchanged between cohorts, suggesting no overt mitophagy defects. Expression levels of the parkin substrates, VDAC, NLRP3, and AIMP2 remained unchanged, suggesting no parkin dysfunction. In summary, we were unable to observe dopaminergic neurodegeneration with corresponding nigral-striatal neurobehavioral deficits, nor Parkin or mitochondrial dysfunction in Parkin-/-/PolgAD257A/D257A mice. These findings support a lack of synergism of Parkin loss on mitochondrial dysfunction in mouse models of mitochondrial deficits.SIGNIFICANCE STATEMENT Producing a mouse model of Parkinson's disease (PD) that is etiologically relevant, recapitulates clinical hallmarks, and exhibits reproducible results is crucial to understanding the underlying pathology and in developing disease-modifying therapies. Here, we show that Parkin-/-/PolgAD257A/D257A mice, a previously reported PD mouse model, fails to reproduce a Parkinsonian phenotype. We show that these mice do not display dopaminergic neurodegeneration nor nigral-striatal-dependent motor deficits. Furthermore, we report that Parkin loss does not synergize with mitochondrial dysfunction. Our results demonstrate that Parkin-/-/PolgAD257A/D257A mice are not a reliable model for PD and adds to a growing body of work demonstrating that Parkin loss does not synergize with mitochondrial dysfunction in mouse models of mitochondrial deficits.


Assuntos
Modelos Animais de Doenças , Dopamina , Mitocôndrias , Doença de Parkinson , Ubiquitina-Proteína Ligases , Animais , Feminino , Masculino , Camundongos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , DNA Polimerase gama/genética , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Doença de Parkinson/metabolismo , Substância Negra/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
2.
Nat Commun ; 14(1): 8161, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38071218

RESUMO

The antibiotic pyrazinamide (PZA) is a cornerstone of tuberculosis (TB) therapy that shortens treatment durations by several months despite being only weakly bactericidal. Intriguingly, PZA is also an anti-inflammatory molecule shown to specifically reduce inflammatory cytokine signaling and lesion activity in TB patients. However, the target and clinical importance of PZA's host-directed activity during TB therapy remain unclear. Here, we identify the host enzyme Poly(ADP-ribose) Polymerase 1 (PARP1), a pro-inflammatory master regulator strongly activated in TB, as a functionally relevant host target of PZA. We show that PZA inhibits PARP1 enzymatic activity in macrophages and in mice where it reverses TB-induced PARP1 activity in lungs to uninfected levels. Utilizing a PZA-resistant mutant, we demonstrate that PZA's immune-modulatory effects are PARP1-dependent but independent of its bactericidal activity. Importantly, PZA's bactericidal efficacy is impaired in PARP1-deficient mice, suggesting that immune modulation may be an integral component of PZA's antitubercular activity. In addition, adjunctive PARP1 inhibition dramatically reduces inflammation and lesion size in mice and may be a means to reduce lung damage and shorten TB treatment duration. Together, these findings provide insight into PZA's mechanism of action and the therapeutic potential of PARP1 inhibition in the treatment of TB.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Animais , Camundongos , Pirazinamida/farmacologia , Pirazinamida/uso terapêutico , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Tuberculose/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Testes de Sensibilidade Microbiana , Poli(ADP-Ribose) Polimerase-1
3.
J Neurosci Res ; 90(9): 1794-802, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22535477

RESUMO

Stem cell therapy is a promising approach for stroke. However, low survival rates and potential tumorigenicity of implanted cells could undermine the efficacy of the cell-based treatment. The use of stem cell-conditioned medium (CM) may be a feasible approach to overcome these limitations. Especially, specific stem cell culture condition and continuous infusion of CM into ischemic brains would have better therapeutic results. The CM was prepared by culturing human adipose-derived stem cells in a three-dimensional spheroid form to increase the secretion of angiogenic/neuroprotective factors. Ischemic stroke was induced by standard middle cerebral artery occlusion methods in the brain of 8-week-old Sprague-Dawley rats. Continuous infusion of CM or αMEM media (0.5 µl/hr) into the lateral ventricle was initiated 8 days after the surgery and maintained for 7 days. Alteration in the motor function was monitored by the rotarod test. Infarction volume and the number of microvessels or TUNEL-positive neural cells were analyzed 15 days after the surgery. Compared with αMEM, continuous CM infusion reduced the infarction volume and maintained motor function. The number of CD31-positive microvessels and TUNEL-positive neural cells significantly increased and decreased, respectively, in the penumbra regions. Although the apoptosis of all neural cell types decreased, reduction in the microglial apoptosis and astrogliosis was prominent and significant. In this study, the therapeutic effects of the CM against stroke were confirmed in an animal model. Increased endothelial cell proliferation, reduced neural cell apoptosis, and milder astrogliosis may play important roles in the treatment effects of CM.


Assuntos
Indutores da Angiogênese/farmacologia , Meios de Cultivo Condicionados/farmacologia , Células-Tronco/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Tecido Adiposo/citologia , Animais , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia Confocal , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/patologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-35206277

RESUMO

Respiratory sinus arrhythmia (RSA) is a phenomenon in which the heart rate (HR) changes with respiration, increasing during inspiration and decreasing during expiration. RSA biofeedback training has an effect in relieving negative mental conditions, such as anxiety and stress. Respiration is an important indicator affecting the parasympathetic activation within the body during RSA biofeedback training. Although there are existing studies that consider individual differences when selecting optimized respiration using heart rate variability, the studies that use the high frequency components of HRV, which is an indicator of parasympathetic activation, are insufficient. For this reason, this paper proposes a process to identify optimized respiration for efficient RSA feedback, consisting of three steps: (1) application, (2) optimization, and (3) validation. In the application phase, we measured PPG data against various respiratory cycles based on the HF components of HRV and calculated the proposed heart stabilization indicator (HSI) from the data. Then, we determined the optimized respiration cycle based on the HSI in the optimization step. Finally, we analyzed seven stress-related indices against the optimized respiration cycle. The experimental results show that HSI is associated with the parasympathetic nervous system activation, and the proposed method could help to determine the optimal respiratory cycle for each individual. Lastly, we expect that the proposed design could be used as an alternative to improving the efficiency of RSA biofeedback training.


Assuntos
Arritmia Sinusal Respiratória , Arritmia Sinusal , Biorretroalimentação Psicológica/métodos , Frequência Cardíaca/fisiologia , Humanos , Respiração
5.
Sci Adv ; 8(13): eabh1824, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35363524

RESUMO

Mutations in PINK1 and parkin highlight the mitochondrial axis of Parkinson's disease (PD) pathogenesis. PINK1/parkin regulation of the transcriptional repressor PARIS bears direct relevance to dopamine neuron survival through augmentation of PGC-1α-dependent mitochondrial biogenesis. Notably, knockout of PARIS attenuates dopaminergic neurodegeneration in mouse models, indicating that interventions that prevent dopaminergic accumulation of PARIS could have therapeutic potential in PD. To this end, we have identified the deubiquitinase cylindromatosis (CYLD) to be a regulator of PARIS protein stability and proteasomal degradation via the PINK1/parkin pathway. Knockdown of CYLD in multiple models of PINK1 or parkin inactivation attenuates PARIS accumulation by modulating its ubiquitination levels and relieving its repressive effect on PGC-1α to promote mitochondrial biogenesis. Together, our studies identify CYLD as a negative regulator of dopamine neuron survival, and inhibition of CYLD may potentially be beneficial in PD by lowering PARIS levels and promoting mitochondrial biogenesis.


Assuntos
Neurônios Dopaminérgicos , Doença de Parkinson , Animais , Enzima Desubiquitinante CYLD/genética , Enzima Desubiquitinante CYLD/metabolismo , Enzimas Desubiquitinantes/metabolismo , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Camundongos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Ubiquitinação
6.
Sci Transl Med ; 14(662): eabq3215, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36103513

RESUMO

Arginine-rich dipeptide repeat proteins (R-DPRs), abnormal translational products of a GGGGCC hexanucleotide repeat expansion in C9ORF72, play a critical role in C9ORF72-related amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), the most common genetic form of the disorders (c9ALS/FTD). R-DPRs form liquid condensates in vitro, induce stress granule formation in cultured cells, aggregate, and sometimes coaggregate with TDP-43 in postmortem tissue from patients with c9ALS/FTD. However, how these processes are regulated is unclear. Here, we show that loss of poly(ADP-ribose) (PAR) suppresses neurodegeneration in c9ALS/FTD fly models and neurons differentiated from patient-derived induced pluripotent stem cells. Mechanistically, PAR induces R-DPR condensation and promotes R-DPR-induced stress granule formation and TDP-43 aggregation. Moreover, PAR associates with insoluble R-DPR and TDP-43 in postmortem tissue from patients. These findings identified PAR as a promoter of R-DPR toxicity and thus a potential target for treating c9ALS/FTD.


Assuntos
Demência Frontotemporal , Arginina , Proteína C9orf72/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dipeptídeos/metabolismo , Demência Frontotemporal/genética , Demência Frontotemporal/metabolismo , Humanos , Poli Adenosina Difosfato Ribose
7.
Artigo em Inglês | MEDLINE | ID: mdl-34769783

RESUMO

This study utilizes modeling and simulation to analyze coronavirus (COVID-19) infection trends depending on government policies. Two modeling requirements are considered for infection simulation: (1) the implementation of social distancing policies and (2) the representation of population movements. To this end, we propose an extended infection model to combine analytical models with discrete event-based simulation models in a hybrid form. Simulation parameters for social distancing policies are identified and embedded in the analytical models. Administrative districts are modeled as a fundamental simulation agent, which facilitates representing the population movements between the cities. The proposed infection model utilizes real-world data regarding suspected, infected, recovered, and deceased people in South Korea. As an application, we simulate the COVID-19 epidemic in South Korea. We use real-world data for 160 days, containing meaningful days that begin the distancing policy and adjust the distancing policy to the next stage. We expect that the proposed work plays a principal role in analyzing how social distancing effectively affects virus prevention and provides a simulation environment for the biochemical field.


Assuntos
COVID-19 , Epidemias , Humanos , Distanciamento Físico , Políticas , SARS-CoV-2
8.
Neuron ; 109(23): 3758-3774.e11, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34644545

RESUMO

Impairment in glucocerebrosidase (GCase) is strongly associated with the development of Parkinson's disease (PD), yet the regulators responsible for its impairment remain elusive. In this paper, we identify the E3 ligase Thyroid Hormone Receptor Interacting Protein 12 (TRIP12) as a key regulator of GCase. TRIP12 interacts with and ubiquitinates GCase at lysine 293 to control its degradation via ubiquitin proteasomal degradation. Ubiquitinated GCase by TRIP12 leads to its functional impairment through premature degradation and subsequent accumulation of α-synuclein. TRIP12 overexpression causes mitochondrial dysfunction, which is ameliorated by GCase overexpression. Further, conditional TRIP12 knockout in vitro and knockdown in vivo promotes the expression of GCase, which blocks α-synuclein preformed fibrils (α-syn PFFs)-provoked dopaminergic neurodegeneration. Moreover, TRIP12 accumulates in human PD brain and α-synuclein-based mouse models. The identification of TRIP12 as a regulator of GCase provides a new perspective on the molecular mechanisms underlying dysfunctional GCase-driven neurodegeneration in PD.


Assuntos
Proteínas de Transporte/metabolismo , Glucosilceramidase , Doença de Parkinson , Ubiquitina-Proteína Ligases/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Camundongos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Ubiquitinação , alfa-Sinucleína/metabolismo
9.
Biochem Biophys Res Commun ; 402(1): 110-5, 2010 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-20920467

RESUMO

We have previously reported that MMTR (MAT1-mediated transcriptional repressor) is a co-repressor that inhibits TFIIH-mediated transcriptional activity via interaction with MAT1 (Kang et al., 2007). Since MAT1 is a member of the CAK kinase complex that is crucial for cell cycle progression and that regulates CDK phosphorylation as well as the general transcription factor TFIIH, we investigated MMTR function in cell cycle progression. We found that MMTR over-expression delayed G1/S and G2/M transitions, whereas co-expression of MAT1 and MMTR rescued the cell growth and proliferation rate. Moreover, MMTR was required for inhibition of CAK kinase-mediated CDK1 phosphorylation. We also showed that the expression level of MMTR was modulated during cell cycle progression. Our data support the notion that MMTR is an intrinsic negative cell cycle regulator that modulates the CAK kinase activity via interaction with MAT1.


Assuntos
Ciclo Celular/genética , Regulação da Expressão Gênica , Receptores Proteína Tirosina Quinases/genética , Proteínas Repressoras/metabolismo , Proteína Quinase CDC2/metabolismo , Divisão Celular/genética , Linhagem Celular , Proliferação de Células , Receptor com Domínio Discoidina 1 , Fase G2/genética , Células HeLa , Humanos , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/metabolismo , Proteínas Repressoras/genética
10.
Mol Cell Biol ; 27(10): 3578-88, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17371848

RESUMO

A transcription corepressor, MAT1-mediated transcriptional repressor (MMTR), was found in mouse embryonic stem cell lines. MMTR orthologs (DMAP1) are found in a wide variety of life forms from yeasts to humans. MMTR down-regulation in differentiating mouse embryonic stem cells in vitro resulted in activation of many unrelated genes, suggesting its role as a general transcriptional repressor. In luciferase reporter assays, the transcriptional repression activity resided at amino acids 221 to 468. Histone deacetylase 1 (HDAC1) interacts with MMTR both in vitro and in vivo and also interacts with MMTR in the nucleus. Interestingly, MMTR activity was only partially rescued by competition with dominant-negative HDAC1(H141A) or by treatment with an HDAC inhibitor, trichostatin A (TSA). To identify the protein responsible for HDAC1-independent MMTR activity, we performed a yeast two-hybrid screen with the full-length MMTR coding sequence as bait and found MAT1. MAT1 is an assembly/targeting factor for cyclin-dependent kinase-activating kinase which constitutes a subcomplex of TFIIH. The coiled-coil domain in the middle of MAT1 was confirmed to interact with the C-terminal half of MMTR, and the MMTR-mediated transcriptional repression activity was completely restored by MAT1 in the presence of TSA. Moreover, intact MMTR was required to inhibit phosphorylation of the C-terminal domain in the RNA polymerase II largest subunit by TFIIH kinase in vitro. Taken together, these data strongly suggest that MMTR is part of the basic cellular machinery for a wide range of transcriptional regulation via interaction with TFIIH and HDAC.


Assuntos
Regulação da Expressão Gênica , Histona Desacetilases/metabolismo , Proteínas Repressoras/metabolismo , Fator de Transcrição TFIIH/metabolismo , Transcrição Gênica , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular , Ciclina H , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Ciclinas/metabolismo , Histona Desacetilase 1 , Histona Desacetilases/genética , Humanos , Camundongos , Modelos Moleculares , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/genética , Fator de Transcrição TFIIH/genética , Fatores de Transcrição , Quinase Ativadora de Quinase Dependente de Ciclina
11.
Mol Ther ; 17(3): 570-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19127251

RESUMO

The tumor-tropic properties of neural stem cells (NSCs) led to the development of a novel strategy for delivering therapeutic genes to tumors in the brain. To apply this strategy to the treatment of brain metastases, we made a human NSC line expressing cytosine deaminase (F3.CD), which converts 5-fluorocytosine (5-FC) into 5-fluorouracil, an anticancer agent. In vitro, the F3.CD cells significantly inhibited the growth of tumor cell lines in the presence of the prodrug 5-FC. In vivo, MDA-MB-435 human breast cancer cells were implanted into the brain of immune-deficient mouse stereotactically, and F3.CD cells were injected into the contralateral hemisphere followed by systemic 5-FC administration. The F3.CD cells migrated selectively into the brain metastases located in the opposite hemisphere and resulted in significantly reduced volumes. The F3.CD and 5-FC treatment also decreased both tumor volume and number of tumor mass significantly, when immune-deficient mouse had MDA-MB-435 cells injected into the internal carotid artery and F3.CD cells were transplanted into the contralateral brain hemisphere stereotactically. Taken together, brain transplantation of human NSCs, encoding the suicide enzyme CD, combined with systemic administration of the prodrug 5-FC, is an effective treatment regimen for brain metastases of tumors.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Células-Tronco/metabolismo , Animais , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/secundário , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Linhagem Celular , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Citosina Desaminase/genética , Citosina Desaminase/metabolismo , Flucitosina/farmacologia , Terapia Genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
12.
PLoS One ; 15(4): e0231978, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32315348

RESUMO

Ischemic strokes result in the death of brain tissue and a wave of downstream effects, often leading to lifelong disabilities or death. However, the underlying mechanisms of ischemic damage and repair systems remain largely unknown. In order to better understand these mechanisms, TMT-isobaric mass tagging and mass spectrometry were conducted on brain cortex extracts from mice subjected to one hour of middle cerebral artery occlusion (MCAO) and after one hour of reperfusion. In total, 2,690 proteins were identified and quantified, out of which 65% of the top 5% of up- and down-regulated proteins were found to be significant (p < 0.05). Network-based gene ontology analysis was then utilized to cluster all identified proteins by protein functional groups and cellular roles. Although three different cellular functions were identified-organelle outer membrane proteins, cytosolic ribosome proteins, and spliceosome complex proteins-several functional domains were found to be common. Of these, organelle outer membrane proteins were downregulated whereas cytosolic ribosome and spliceosome complex proteins were upregulated, indicating that major molecular events post-stroke were translation-associated and subsequent signaling pathways (e.g., poly (ADP-ribose) (PAR) dependent cell death). By approaching stroke analyses via TMT-isobaric mass tagging, the work herein presents a grand scope of protein-based molecular mechanisms involved with ischemic stroke recovery.


Assuntos
Córtex Cerebral/metabolismo , Espectrometria de Massas/métodos , Proteoma/metabolismo , Acidente Vascular Cerebral/patologia , Animais , Modelos Animais de Doenças , Regulação para Baixo , Ontologia Genética , Infarto da Artéria Cerebral Média/complicações , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Proteoma/análise , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteínas Ribossômicas/metabolismo , Transdução de Sinais/genética , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/metabolismo , Regulação para Cima
13.
Lab Invest ; 88(8): 808-15, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18560366

RESUMO

A number of recent reports have demonstrated that only CD133-positive cancer cells of glioblastoma multiforme (GBM) have tumor-initiating potential. These findings raise an attractive hypothesis that GBMs can be cured by eradicating CD133-positive cancer stem cells (CSCs), which are a small portion of GBM cells. However, as GBMs are known to possess various genetic alterations, GBMs might harbor heterogeneous CSCs with different genetic alterations. Here, we compared the clinical characteristics of two GBM patient groups divided according to CD133-positive cell ratios. The CD133-low GBMs showed more invasive growth and gene expression profiles characteristic of mesenchymal or proliferative subtypes, whereas the CD133-high GBMs showed features of cortical and well-demarcated tumors and gene expressions typical of proneuronal subtype. Both CD133-positive and CD133-negative cells purified from four out of six GBM patients produced typical GBM tumor masses in NOD-SCID brains, whereas brain mass from CD133-negative cells showed more proliferative and angiogenic features compared to that from CD133-positive cells. Our results suggest, in contrast to previous reports that only CD133-positive cells of GBMs can initiate tumor formation in vivo CD133-negative cells also possess tumor-initiating potential, which is indicative of complexity in the identification of cancer cells for therapeutic targeting.


Assuntos
Antígenos CD/metabolismo , Neoplasias Encefálicas/imunologia , Glioblastoma/imunologia , Glicoproteínas/metabolismo , Células-Tronco Neoplásicas/imunologia , Peptídeos/metabolismo , Antígeno AC133 , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Células Cultivadas , Resistencia a Medicamentos Antineoplásicos/imunologia , Feminino , Perfilação da Expressão Gênica , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade
14.
Int J Oncol ; 33(4): 705-12, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18813783

RESUMO

P-glycoprotein (P-gp), a factor responsible for the multidrug resistance of tumors, is specifically expressed in brain microenvironment. To test its roles in brain metastatic tumor chemoresistance, we implanted the paclitaxel-sensitive melanoma cell line, K1735, into the skin or brain of mice and examined its paclitaxel resistances. When implanted into the skin, paclitaxel inhibited tumor growth, however, it had no inhibitory effect on cells implanted into the brain. The paclitaxel resistance of the brain K1735 tumors was eliminated by combined treatment with a P-gp inhibitor, HM30181A, and paclitaxel. Previously we found that there is a defined therapeutic window for combined treatment of brain tumors with HM30181A and paclitaxel. To determine whether it is due to responses of the brain microenvironment we measured changes in P-gp expression and function of brain endothelial cells in response to HM30181A treatment in vitro and in vivo. They were significantly increased by high-dose HM30181A treatment and it was related with the therapeutic effect loss of high-dose HM30181A treatment. Therefore, P-gp in the brain microenvironment has crucial roles in the brain metastatic tumor chemoresistance and brain microenvironment responses to P-gp inhibitor treatment should be considered in the development of brain endothelial cell-targeted chemotherapy using P-gp inhibitor.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Encéfalo/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais , Antineoplásicos/farmacologia , Benzopiranos/farmacologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Isoquinolinas/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Metástase Neoplásica , Transplante de Neoplasias , Paclitaxel/farmacologia , Tetrazóis/farmacologia
15.
J Neurol ; 264(5): 848-855, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28220291

RESUMO

To determine the immediate and short-term efficacies of mastoid oscillation vs. Gufoni maneuver in treating the apogeotropic type of horizontal canal benign paroxysmal positional vertigo (HC-BPPV), we designed a randomized, prospective, sham-controlled study. In eight dizziness clinics in Korea, 209 consecutive patients with apogeotropic HC-BPPV were enrolled. The patients were randomly assigned to receive a single application of Gufoni (n = 70), mastoid oscillation (n = 67), or sham maneuver (n = 72). Immediate and second-day responses were determined based on the results within 1 h after a single trial of each maneuver and the following day, respectively. Second-day response was assessed in patients who were non-responders on the first day. The short-term response was determined based on the cumulative response for 2 days. Successful treatment was defined as a resolution of positional nystagmus or as a transition into geotropic horizontal nystagmus (not requires vertigo symptom resolution). The immediate responses of the Gufoni maneuver (33/70, 47.1%) and mastoid oscillation (32/67, 47.8%) were better than the sham maneuver (14/72, 19.4%) (p = 0.00). The second-day results did not differ among the three groups (p = 0.76). The short-term responses showed better efficacies with the Gufoni maneuver (51/70, 76.1%) and mastoid oscillation (46/67, 71.9%) than with the sham maneuver (38/72, 53.5%) (p = 0.02). Therapeutic efficacies did not differ between the Gufoni and mastoid oscillation groups in terms of both immediate and short-term outcomes (p = 0.94, 0.57). Both the Gufoni maneuver and mastoid oscillation are valid methods for treating apogeotropic HC-BPPV, with a success rate of approximately 70% for a single maneuver during the short-term follow-up. TRIAL REGISTRATION: clinicaltrials.gov identifier number: NCT02046980.


Assuntos
Terapia por Exercício/métodos , Processo Mastoide/fisiologia , Nistagmo Fisiológico/fisiologia , Vibração , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Vertigem Posicional Paroxística Benigna/terapia , Feminino , Movimentos da Cabeça/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Postura , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
16.
eNeuro ; 3(4)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27622213

RESUMO

Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder. Recent studies have implicated a role for peroxisome proliferator-activated receptor γ coactivator protein-1α (PGC-1α) in PD and in animal or cellular models of PD. The role of PGC-1α in the function and survival of substantia nigra pars compacta (SNpc) dopamine neurons is not clear. Here we find that there are four different PGC-1α isoforms expressed in SH-SY5Y cells, and these four isoforms are expressed across subregions of mouse brain. Adult conditional PGC-1α knock-out mice show a significant loss of dopaminergic neurons that is accompanied by a reduction of dopamine in the striatum. In human PD postmortem tissue from the SNpc, there is a reduction of PGC-1α isoforms and mitochondria markers. Our findings suggest that all four isoforms of PGC-1α are required for the proper expression of mitochondrial proteins in SNpc DA neurons and that PGC-1α is essential for SNpc DA neuronal survival, possibly through the maintenance of mitochondrial function.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Idoso , Idoso de 80 Anos ou mais , Anfetamina/farmacologia , Animais , Morte Celular/fisiologia , Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos Knockout , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Parte Compacta da Substância Negra/efeitos dos fármacos , Parte Compacta da Substância Negra/metabolismo , Parte Compacta da Substância Negra/patologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Isoformas de Proteínas , Distribuição Aleatória
17.
Anat Cell Biol ; 48(1): 44-53, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25806121

RESUMO

Glioblastoma multiforme (GBM) is the most malignant World Health Organization grade IV brain tumor. GBM patients have a poor prognosis because of its resistance to standard therapies, such as chemotherapy and radiation. Since stem-like cells have been associated with the treatment resistance of GBM, novel therapies targeting the cancer stem cell (CSC) population is critically required. However, GBM CSCs share molecular and functional characteristics with normal neural stem cells (NSCs). To elucidate differential therapeutic targets of GBM CSCs, we compared surface markers of GBM CSCs with adult human NSCs and found that GD2 and CD90 were specifically overexpressed in GBM CSCs. We further tested whether the GBM CSC specific markers are associated with the cancer stemness using primarily cultured patient-derived GBM cells. However, results consistently indicated that GBM cells with or without GD2 and CD90 had similar in vitro sphere formation capacity, a functional characteristics of CSCs. Therefore, GD2 and CD90, GBM specific surface markers, might not be used as specific therapeutic targets for GBM CSCs, although they could have other clinical utilities.

18.
FEBS Lett ; 566(1-3): 307-10, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15147914

RESUMO

We have used cationic oligopeptide polyarginine-12mer (POA) to deliver double-stranded RNA (dsRNA), prepared in vitro, to tobacco (Nicotiana tabacum) suspension cells. POA interacts electrostatically with dsRNA to form a complex. When dsRNA for the GUS or NPTII gene was delivered into cells carrying the same genes, the corresponding mRNA was degraded. Using RNase protection assay we were able to detect 21-bp small interfering RNA in dsRNA/POA-treated cells. These results demonstrate that POA can be used to deliver dsRNA to induce post-transcriptional gene silencing in plant cells.


Assuntos
Nicotiana/genética , Oligopeptídeos/química , Peptídeos/química , Interferência de RNA , RNA de Cadeia Dupla/química , RNA de Cadeia Dupla/genética , Northern Blotting , Cátions , Células Cultivadas , Genes de Plantas/genética , Brotos de Planta/citologia , Plantas Geneticamente Modificadas/citologia , RNA de Cadeia Dupla/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/biossíntese , Nicotiana/citologia , Nicotiana/ultraestrutura
19.
Org Lett ; 6(25): 4655-8, 2004 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-15575653

RESUMO

[structure: see text] A new cavitand bearing four imidazolium groups was synthesized for the recognition of anions through (C-H)+...X- hydrogen bond formation. The binding properties toward various anions including dicarboxylates were examined on the basis of 1H NMR spectroscopic experiments.

20.
Exp Neurol ; 240: 168-77, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23201097

RESUMO

Autologous adult human neural stem cells may be used for regenerative cell therapies bypass potential ethical problems. However, stable in vitro expansion protocols and experimental/clinical factors influencing primary cultures need to be further elucidated for clinically applicable techniques. To address these issues, we obtained biopsy specimens from 23 temporal lobe epilepsy patients and adult human multipotent neural cells (ahMNCs) were primarily cultured in a defined attachment culture condition. When the success of primary cultures was defined as stable expansion of cells (>ten in vitro passages) and expression of NSC markers, success rate of the primary culture was 39% (nine of 23 temporal lobes). During the long-term expansion, expressions of NSC markers and differentiation potentials into astrocytes and neurons were maintained. After the 18th sub-culture, spontaneous senescence and differentiation were observed, and the cultivated ahMNCs ceased their proliferation. The culture results were not affected by seizure characteristics; however, an older age (>40 years) and a smaller sample volume (<2 ml) were found to exert negative influences on the primary culture results. Furthermore therapeutic effects of ahMNCs against stroke were analyzed in an animal model. Transplantation of ahMNCs cells reduced infarction volumes and enhanced motor activity, significantly. The results here would provide promising experimental and clinical strategy of using patient-specific autologous ahMNCs in regenerative medicine in the future.


Assuntos
Células-Tronco Adultas/citologia , Epilepsia do Lobo Temporal/fisiopatologia , Infarto da Artéria Cerebral Média/terapia , Células-Tronco Multipotentes/citologia , Células-Tronco Neurais/citologia , Lobo Temporal/citologia , Adolescente , Adulto , Células-Tronco Adultas/transplante , Animais , Criança , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Multipotentes/transplante , Células-Tronco Neurais/transplante , Cultura Primária de Células/métodos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA