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1.
Front Neurol ; 13: 813597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392634

RESUMO

Objective: Post-stroke cognitive impairment (PSCI) is resistant to treatment. Recent studies have widely applied repetitive transcranial magnetic stimulation (rTMS) to treat various brain dysfunctions, such as post-stroke syndromes. Nonetheless, a protocol for PSCI has not been established. Therefore, this study is aimed to evaluate the therapeutic effect of our high-frequency rTMS protocol for PSCI during the chronic phase of stroke. Methods: In this prospective study, ten patients with PSCI were enrolled and received high-frequency rTMS on the ipsilesional dorsolateral prefrontal cortex (DLPFC) for 10 sessions (5 days per week for 2 weeks). Cognitive and affective abilities were assessed at baseline and 2 and 14 weeks after rTMS initiation. To investigate the therapeutic mechanism of rTMS, the mRNA levels of pro-inflammatory cytokines (interleukin (IL)-6, IL-1ß, transforming growth factor beta [TGF-ß], and tumor necrosis factor alpha [TNF-α]) in peripheral blood samples were quantified using reverse transcription polymerase chain reaction, and cognitive functional magnetic resonance imaging (fMRI) was conducted at baseline and 14 weeks in two randomly selected patients after rTMS treatment. Results: The scores of several cognitive evaluations, i.e., the Intelligence Quotient (IQ) of Wechsler Adult Intelligence Scale, auditory verbal learning test (AVLT), and complex figure copy test (CFT), were increased after completion of the rTMS session. After 3 months, these improvements were sustained, and scores on the Mini-Mental Status Examination and Montreal Cognitive Assessment (MoCA) were also increased (p < 0.05). While the Geriatric Depression Scale (GeDS) did not show change among all patients, those with moderate-to-severe depression showed amelioration of the score, with marginal significance. Expression of pro-inflammatory cytokines was decreased immediately after the ten treatment sessions, among which, IL-1ß remained at a lower level after 3 months. Furthermore, strong correlations between the decrease in IL-6 and increments in AVLT (r = 0.928) and CFT (r = 0.886) were found immediately after the rTMS treatment (p < 0.05). Follow-up fMRI revealed significant activation in several brain regions, such as the medial frontal lobe, hippocampus, and angular area. Conclusions: High-frequency rTMS on the ipsilesional DLPFC may exert immediate efficacy on cognition with the anti-inflammatory response and changes in brain network in PSCI, lasting at least 3 months.

2.
Front Neurol ; 10: 357, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024439

RESUMO

Disruption of blood flow in the brain induces stroke, the leading cause of death and disability worldwide. However, so far the therapeutic options are limited. Thus, the therapeutic efficacy of cell-based approaches has been investigated to develop a potential strategy to overcome stroke-induced disability. Human umbilical cord blood cells (hUCBCs) and erythropoietin (EPO) both have angiogenic and neurogenic properties in the injured brain, and their combined administration may exert synergistic effects during neurological recovery following stroke. We investigated the therapeutic potential of hUCBC and EPO combination treatment by comparing its efficacy to those of hUCBC and EPO alone. Adult male Sprague-Dawley rats underwent transient middle cerebral artery occlusion (MCAO). Experimental groups were as follows: saline (injected once with saline 7 d after MCAO); hUCBC (1.2 × 107 total nucleated cells, injected once via the tail vein 7 d after MCAO); EPO (500 IU/kg, injected intraperitoneally for five consecutive days from 7 d after MCAO); and combination of hUCBC and EPO (hUCBC+EPO). Behavioral measures (Modified Neurological Severity Score [mNSS] and cylinder test) were recorded to assess neurological outcomes. Four weeks after MCAO, brains were harvested to analyze the status of neurogenesis and angiogenesis. In vitro assays were also conducted using neural stem and endothelial cells in the oxygen-glucose deprivation condition. Performance on the mNSS and cylinder test showed the most improvement in the hUCBC+EPO group, while hUCBC- and EPO-alone treatments showed superior outcomes relative to the saline group. Neurogenesis and angiogenesis in the cortical region was the most enhanced in the hUCBC+EPO group, while the findings in the hUCBC and EPO treatment alone groups were better than those in the saline group. Astrogliosis in the brain tissue was reduced by hUCBC and EPO treatment. The reduction was largest in the hUCBC+EPO group. These results were consistent with in vitro assessments that showed the strongest neurogenic and angiogenic effect with hUCBC+EPO treatment. This study demonstrates that combination therapy is more effective than single therapy with either hUCBC or EPO for neurological recovery from subacute stroke. The common pathway underlying hUCBC and EPO treatment requires further study.

3.
Oncotarget ; 6(34): 36551-76, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26427597

RESUMO

14-3-3 is a family of highly conserved protein that is involved in a number of cellular processes. In this study, we identified that the high expression of 14-3-3γ in various cancer cell lines correlates with the invasiveness of the cancer cells. Overexpression of 14-3-3γ causes changes to the morphologic characteristics of cell transformation, and promotes cell migration and invasion. The cells overexpressed with 14-3-3γ have been shown to stimulate foci and tumor formation in SCID-NOD mice in concert with signaling components as reported with the 14-3-3ß. In our previous study, we demonstrated that 14-3-3γ inhibits apoptotic cell death and mediates the promotion of cell proliferation in immune cell lines. Earlier, binding partners for 14-3-3γ were defined by screening. We found that USP37, one of deubiquitinating enzymes (DUBs), belongs to this binding partner group. Therefore, we investigated whether 14-3-3γ mediates proliferation in cancer cells, and 14-3-3γ by USP37 is responsible for promoting cell proliferation. Importantly, we found that USP37 regulates the stability of ubiquitin-conjugated 14-3-3γ through its catalytic activity. This result implies that the interactive behavior between USP37 and 14-3-3γ could be involved in the regulation of 14-3-3γ degradation. When all these findings are considered together, USP37 is shown to be a specific DUB that prevents 14-3-3γ degradation, which may contribute to malignant transformation via MAPK signaling pathway, possibly providing a new target for therapeutic objectives of cancer.


Assuntos
Proteínas 14-3-3/metabolismo , Enzimas Desubiquitinantes/metabolismo , Animais , Apoptose/fisiologia , Endopeptidases/metabolismo , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células NIH 3T3 , Transdução de Sinais , Transfecção
4.
Artigo em Inglês | MEDLINE | ID: mdl-22364277

RESUMO

UNLABELLED: Abstract Aims: The fate decision of adult stem cells is determined by the activation of specific intracellular signaling pathways after exposure to specific stimuli. In this study, we demonstrated specific functions of a novel small molecule, CBM-1078, that induced cell self-renewal via Oct4- and canonical Wnt/ß-catenin-mediated deaging in cultured human adipose tissue-derived stem cells (hATSCs). RESULTS: As a potential glycogen synthase kinase-3ß (GSK-3ß) inhibitor, CBM-1078 primarily activated ß-catenin and Oct4 expression after inhibition of GSK-3ß. Treatment of hATSCs with CBM-1078 led to transdifferentiation toward a neural precursor cell fate after transient self-renewal, and the cells were capable of differentiation into gamma-Aminobutyric acid (GABA)-secreting neuronal cells with pain-modulating functions in an animal model of neuropathic pain. During cell self-renewal, CBM-1078 directs the translocalization of ß-catenin and Oct4 into the nucleus, an event that is crucial for the cooperative activation of hATSC neurogenesis via Oct4 and Wnt/ß-catenin. Nuclear-localized ß-catenin and Oct4 act together to regulate the expression of Oct4, Nanog, Sox2, ß-catenin, c-Myc, and STAT3 after binding to the regulatory regions of these genes. Nuclear Oct4 and Wnt3a/ß-catenin also control cell growth by binding to the promoters of STAT3, Gli3, and c-Myc after complex formation and direct interaction. CBM-1078 actively enhanced the DNA-binding affinity of Oct4 and ß-catenin to functional genes and activated the Wnt/ß-catenin pathway to promote hATSC reprogramming. INNOVATION AND CONCLUSION: This study revealed the value of a single small molecule, CBM-1078, showing a definitive cell reprogramming mechanism. Finally, we confirmed the therapeutic potential of GABA-hATSCs for treatment of neuropathic pain, which could be used for therapeutic purposes in humans. Antioxid. Redox Signal. 00, 000-000.

5.
Hum Gene Ther ; 22(12): 1551-62, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21810014

RESUMO

In the present study, we show that Rex-1 mRNA and protein are found at high levels in both 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU)-resistant glioma cell subpopulations and malignant glioblastoma multiforme (GBM) tissue. We used a combination therapy of small interfering RNA (siRNA) against Rex-1 (siRex-1) and BCNU to target GBM cells. Rex-1 siRNA/BCNU treatment resulted in growth inhibition and a diminished S phase. The treatment efficiently induced P38/JNK and Akt/PI3K/GSK3ß signaling and led to apoptosis both in vitro and in vivo. We also show that Rex-1/ABCG2 (ATP binding cassette transporter G2)-coexpressing subpopulations were chemoresistant; however, BCNU was not a substrate for ABCG2. siRex-1 treatment led to cell death in GBM subpopulations by promoting apoptosis. Moreover, siRex-1/BCNU combination therapy targeted both the major population and cancer stem cell-like subpopulations. Our findings are important for the development of clinical applications to treat GBM.


Assuntos
Apoptose , Carmustina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Glioma/tratamento farmacológico , Glioma/metabolismo , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , RNA Interferente Pequeno/genética , Animais , Antineoplásicos/uso terapêutico , Western Blotting , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Metilação de DNA , Feminino , Glioma/genética , Humanos , Técnicas Imunoenzimáticas , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Células Tumorais Cultivadas
6.
Biomaterials ; 32(29): 7013-22, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21705075

RESUMO

In stem cell biology, cell plasticity refers to the ability of stem cells to differentiate into a variety of cell lineages. Recently, cell plasticity has been used to refer to the ability of a given cell type to reversibly de-differentiate, re-differentiate, or transdifferentiate in response to specific stimuli. These processes are regulated by multiple intracellular and extracellular growth and differentiation factors, including low oxygen. Our recent study showed that 3D microfluidic cell culture induces activation of the Wnt5A/ß-catenin signaling pathway in hATSCs (human Adipose Tissue-derived Stem Cells). This resulted in self renewal and transdifferentiation of hATSCs into neurons. To improve neurogenic potency of hATSCs in response to low oxygen and other unknown physical factors, we developed a gel-free 3D microfluidic cell culture system (3D-µFCCS). The functional structure was developed for the immobilization of 3D multi-cellular aggregates in a microfluidic channel without the use of a matrix on the chip. Growth of hATSCs neurosphere grown on a chip was higher than the growth of control cells grown in a culture dish. Induction of differentiation in the Chip system resulted in a significant increase in the induction of neuronal-like cell structures and the presentation of TuJ or NF160 positive long neuritis compared to control cells after active migration from the center of the microfluidic channel layer to the outside of the microfluidic channel layer. We also observed that the chip neurogenesis system induced a significantly higher level of GABA secreting neurons and, in addition, almost 60% of cells were GABA + cells. Finally, we observed that 1 month of after the transplantation of each cell type in a mouse SCI lesion, chip cultured and neuronal differentiated hATSCs exhibited the ability to effectively transdifferentiate into NF160 + motor neurons at a high ratio. Interestingly, our CHIP/PCR analysis revealed that HIF1α-induced hATSCs neurogenesis on the chip. This induction was a result of the direct binding of HIF1α to the regulatory regions of the Oct4 and ß-catenin genes in nucleus. In the Chip culture of hATSCs that we developed, a low oxygen microenvironment was induced. The low oxygen level induced HIF1α expression, which resulted in increased expression of Wnt5A/ß-catenin and Oct4 via the direct binding of HIF1α to the regulatory regions of ß-catenin and Oct4.


Assuntos
Tecido Adiposo/citologia , Técnicas de Cultura de Células/métodos , Microfluídica/métodos , Neurogênese/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Células-Tronco/fisiologia , Proteínas Wnt/metabolismo , Animais , Técnicas de Cultura de Células/instrumentação , Proliferação de Células , Sobrevivência Celular , Transdiferenciação Celular/fisiologia , Células Cultivadas , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Neurônios/citologia , Neurônios/fisiologia , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco/citologia , Proteína Wnt-5a , beta Catenina/metabolismo
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