Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 13(1): 5490, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-37016000

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is attracting attention as a new treatment technique for brain lesions, and many animal studies showing its effects have been reported. However, the findings of animal application researches cannot directly represent the effects of rTMS in human, mainly due to size difference and mechanistic characteristics of rTMS. Therefore, the authors purposed to develop a mouse rTMS to simulate clinical application and to confirm. Firstly, a virtual head model was created according to magnetic resonance images of murine head. Then, simulations of rTMS stimulation with different coils were performed on the murine head phantom, and an rTMS device for mice was fabricated based on the optimal voltage conditions. Lastly, strengths of magnetic fields generated by the two rTMS devices, for human (conventional clinical use) and mouse (newly fabricated), were measured in air and on mouse head and compared. Resultantly, the magnetic field intensity generated by coil of mouse was lower than human's (p < 0.01), and no differences were found between the predicted simulation values and the measured intensity in vivo (p > 0.05). Further in vivo researches using miniaturized rTMS devices for murine head should be followed to be more meaningful for human.


Assuntos
Campos Magnéticos , Estimulação Magnética Transcraniana , Humanos , Camundongos , Animais , Estimulação Magnética Transcraniana/métodos , Modelos Animais de Doenças , Simulação por Computador
2.
Life (Basel) ; 13(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36676176

RESUMO

Systemic administration of mesenchymal stem cells (MSCs) has been reported to improve neurological function in brain damage, including hypoxic-ischemic encephalopathy (HIE), though the action mechanisms have not been fully elucidated. In this study, the cells were tracked live using a Pearl Trilogy Small Animal fluorescence imaging system after human embryonic stem Cell-Derived MSCs (ES-MSCs) infusion for an HIE mouse model. ES-MSC-treated HIE mice showed neurobehavioral improvement. In vivo imaging showed similar sequential migration of ES-MSCs from lungs, liver, and spleen within 7 days in both HIE and normal mice with the exception of lungs, where there was higher entrapment in the HIE 1 h after infusion. In addition, ex vivo experiments confirmed time-dependent infiltration of ES-MSCs into the organs, with similar findings in vivo, although lungs and brain revealed small differences. ES-MSCs seemed to remain in the brain only in the case of HIE on day 14 after the cell infusion. The homing effect in the host brain was confirmed with immunofluorescence staining, which showed that grafted cells remained in the brain tissue at the lesion area with neurorestorative findings. Further research should be carried out to elucidate the role of each host organ's therapeutic effects when stem cells are systemically introduced.

3.
Int J Mol Sci ; 23(15)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35897720

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease characterized by memory impairment in patients. Erythropoietin (EPO) has been reported to stimulate neurogenesis. This study was conducted to determine the regenerative effects of EPO in an AD model and to assess its underlying mechanism. Recombinant human EPO was intraperitoneally administered to AD mice induced by intracerebroventricular Aß oligomer injection. Behavioral assessments with novel object recognition test and passive avoidance task showed improvement in memory function of the EPO-treated AD mice compared to that of the saline-treated AD mice (p < 0.0001). An in vivo protein assay for the hippocampus and cortex tissue indicated that EPO treatment modulated neurotransmitters, including dopamine, serotonin, and adrenaline. EPO treatment also restored the activity of serotonin receptors, including 5-HT4R, 5-HT7R, and 5-HT1aR (p < 0.01), at mRNA levels. Furthermore, EPO seemed to exert an anti-inflammatory influence by downregulating TLR4 at mRNA and protein levels (p < 0.05). Finally, an immunohistochemical assay revealed increments of Nestin(+) and NeuN(+) neuronal cells in the CA3 region in the EPO-treated AD mice compared to those in the saline-treated AD mice. The conclusion is that EPO administration might be therapeutic for AD by activating the serotonergic pathway, anti-inflammatory action, and neurogenic characteristics.


Assuntos
Doença de Alzheimer , Eritropoetina , Doenças Neurodegenerativas , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Epoetina alfa/uso terapêutico , Eritropoetina/metabolismo , Eritropoetina/farmacologia , Eritropoetina/uso terapêutico , Hipocampo/metabolismo , Humanos , Camundongos , Doenças Neurodegenerativas/metabolismo , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Serotonina/metabolismo
4.
Int J Mol Sci ; 22(22)2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34830197

RESUMO

Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare premature aging disorder characterized by short stature and atherosclerosis-induced death within teenage years. A 13-year-old male diagnosed with HGPS was administered three intravenous infusions of allogeneic cord blood (CB) cells from unrelated donors at four-month intervals to evaluate the safety and its therapeutic efficacy. Adverse events were monitored in addition to height, weight, laboratory blood tests, joint range of motion (ROM), and carotid Doppler. Cytokine and receptor assays were also performed. The patient exhibited an increase in growth rate for both height and weight. One year after therapy initiation, evident amelioration in pulse wave velocity, bilateral maximal intima-media thickness, and dyslipidemic status were observed, which were in abrupt aggravation prior to treatment. Further, an increase in flexibility occurred in some joints of the upper extremities. No serious adverse events were observed throughout the study period and one year beyond. A molecular assay revealed downregulation of proinflammatory and atherosclerosis, representing cytokine expressions following the administration of CB cells. This is the first reported case of an allogeneic CB trial in a patient with HGPS showing therapeutic effects of CB with improvements in anthropometric measures, joint ROM with amelioration of atherosclerosis, and dyslipidemia induced by anti-inflammatory and anti-atherosclerotic responses.


Assuntos
Aterosclerose/complicações , Aterosclerose/terapia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Dislipidemias/complicações , Dislipidemias/terapia , Progéria/complicações , Progéria/terapia , Adolescente , Estatura , Seguimentos , Humanos , Masculino , Análise de Onda de Pulso , Amplitude de Movimento Articular , Transplante Homólogo/efeitos adversos , Resultado do Tratamento , Aumento de Peso
5.
Int J Mol Sci ; 22(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34769434

RESUMO

Our previous clinical studies demonstrated the synergistic therapeutic effect induced by co-administering recombinant human erythropoietin (rhEPO) in human umbilical cord blood (hUCB) therapy for children with cerebral palsy. However, the cellular mechanism beyond the beneficial effects in this combination therapy still needs to be elucidated. A hypoxic-ischemic encephalopathy (HIE) model of neonates, representing cerebral palsy, was prepared and randomly divided into five groups (hUCB+rhEPO combination, hUCB, and rhEPO treatments over HIE, HIE control, and sham). Seven days after, hUCB was administered intraperitoneally and the rhEPO injections were started. Neurobehavioral tests showed the best outcome in the combination therapy group, while the hUCB and rhEPO alone treatments also showed better outcomes compared with the control (p < 0.05). Inflammatory cytokines were downregulated by the treatments and attenuated most by the combination therapy (p < 0.05). The hUCB+rhEPO treatment also showed remarkable increase in phosphorylation of Akt and potentiation of anti-apoptotic responses with decreased Bax and increased Bcl-2 (p < 0.05). Pre-treatment of MK-2206, an Akt inhibitor, for the combination therapy depressed the anti-apoptotic effects. In conclusion, these findings suggest that the therapeutic effect of hUCB therapy might be potentiated by co-administration of rhEPO via augmentation of anti-inflammatory and anti-apoptotic responses related to the phosphorylation of Akt.


Assuntos
Lesões Encefálicas/terapia , Eritropoetina/farmacologia , Sangue Fetal/transplante , Hipóxia-Isquemia Encefálica/terapia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Feminino , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Recombinantes/farmacologia , Transdução de Sinais
7.
Sci Rep ; 11(1): 437, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33432077

RESUMO

Previous studies on repetitive transcranial magnetic stimulation (rTMS) suggested potential neurorestorative properties in Alzheimer's disease (AD). This study aimed to investigate therapeutic effects of rTMS on an AD mouse model at high and low frequencies. The subject mice were allocated into the AD model group (AD induced by intracerebroventricular amyloid beta 42 oligomer [Aß42] injection) and the saline-injected control group. Each group was subdivided according to rTMS treatment: high frequency (20 Hz), low frequency (1 Hz), and not rTMS-treated. Behavioural assessments with Y-maze test and novel object recognition task were performed; the results indicated cognition recovery by both the frequencies of rTMS after treatment in the AD model (Ps < 0.01). Tendency of further effects by high frequency compared to low frequency rTMS was also shown in Y-maze test. Neurotransmitter assay showed increment in dopamine concentration and upregulation of dopamine-receptor 4 (DR4) by rTMS in AD mice with higher response by high frequency stimulation (Ps < 0.05). Only high-frequency rTMS induced an elevation of brain-derived neurotrophic factor (BDNF) levels and enhanced the expression of Nestin and NeuN in the brain tissue (Ps < 0.05). Under in vitro conditions, Aß42 incubated mouse hippocampal cell showed an increase in dopamine levels and BDNF by application of high-frequency rTMS treatment. In conclusion, rTMS might have a potential therapeutic effect on AD, and it seems to be related with dopaminergic activation. High frequency of stimulation seems to induce higher efficacy than that induced by low frequency, with elevated expressions of DR4 gene and neurogenic proteins.


Assuntos
Doença de Alzheimer/terapia , Estimulação Magnética Transcraniana , Doença de Alzheimer/patologia , Animais , Comportamento Animal/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Tempo , Estimulação Magnética Transcraniana/métodos , Estimulação Magnética Transcraniana/veterinária , Resultado do Tratamento
8.
ACS Biomater Sci Eng ; 6(10): 5632-5644, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33320585

RESUMO

3D spheroids are considered as the improved in vitro model to mimic the distinct arrangements of the cells in vivo. To date, low-attachment surfaces have been most widely used to induce the spontaneous aggregation of cells in suspension by simply tuning the relative strength of the cell-cell adhesion over cell-substrate adhesion. However, aggregating cancer cells into 3D clusters should mean more than just adjoining the cells in the physical proximity. The tumor cell functionality is strongly affected by the adhesion networks between cancer cells and extracellular matrix (ECM). Here, we performed an in-depth analysis of how the nonmetastatic breast cancer cells (MCF7) can be transformed to gain invasive phenotypes through compact aggregation into 3D spheroids on a functional polymer film surface, poly(2,4,6,8-tetravinyl-2,4,6,8-tetramethyl cyclotetrasiloxane) (pV4D4). By comparing the adhesion networks and invasion dynamics between 3D spheroids cultured on the pV4D4 surface with those cultured on conventional ultra-low-attachment (ULA) dishes, we report that only spheroids on the pV4D4 display active and sporadic cell-surface binding activities via dynamic protrusions, which correlates strongly with an increase in integrin ß1. Moreover, localized laminin expression at the core of the pV4D4-cultured spheroids confirms the prominence of the intimate integrin-laminin interactions prompted by the exposure to pV4D4. This study suggests that structurally and functionally dissimilar 3D spheroids can be generated from the same type of cells on the surfaces of different physicochemical properties without any chemical treatment or genetic manipulation.


Assuntos
Neoplasias , Esferoides Celulares , Adesão Celular , Comunicação Celular , Matriz Extracelular , Polímeros
9.
Diabetes ; 67(12): 2601-2614, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30257975

RESUMO

Glucagon-like peptide 1 (GLP-1) can increase pancreatic ß-cells, and α-cells could be a source for new ß-cell generation. We investigated whether GLP-1 increases ß-cells through α-cell transdifferentiation. New ß-cells originating from non-ß-cells were significantly increased in recombinant adenovirus expressing GLP-1 (rAd-GLP-1)-treated RIP-CreER;R26-YFP mice. Proliferating α-cells were increased in islets of rAd-GLP-1-treated mice and αTC1 clone 9 (αTC1-9) cells treated with exendin-4, a GLP-1 receptor agonist. Insulin+glucagon+ cells were significantly increased by rAd-GLP-1 or exendin-4 treatment in vivo and in vitro. Lineage tracing to label the glucagon-producing α-cells showed a higher proportion of regenerated ß-cells from α-cells in rAd-GLP-1-treated Glucagon-rtTA;Tet-O-Cre;R26-YFP mice than rAd producing ß-galactosidase-treated mice. In addition, exendin-4 increased the expression and secretion of fibroblast growth factor 21 (FGF21) in αTC1-9 cells and ß-cell-ablated islets. FGF21 treatment of ß-cell-ablated islets increased the expression of pancreatic and duodenal homeobox-1 and neurogenin-3 and significantly increased insulin+glucagon+ cells. Generation of insulin+glucagon+ cells by exendin-4 was significantly reduced in islets transfected with FGF21 small interfering RNA or islets of FGF21 knockout mice. Generation of insulin+ cells by rAd-GLP-1 treatment was significantly reduced in FGF21 knockout mice compared with wild-type mice. We suggest that GLP-1 has an important role in α-cell transdifferentiation to generate new ß-cells, which might be mediated, in part, by FGF21 induction.


Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Exenatida/farmacologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Células Secretoras de Glucagon/citologia , Células Secretoras de Insulina/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/genética , Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Glucagon/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Regeneração/efeitos dos fármacos
10.
J Mol Endocrinol ; 58(2): 79-90, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27872157

RESUMO

Glucagon-like peptide-1 (GLP1) has many anti-diabetic actions and also increases energy expenditure in vivo As skeletal muscle is a major organ controlling energy metabolism, we investigated whether GLP1 can affect energy metabolism in muscle. We found that treatment of differentiated C2C12 cells with exendin-4 (Ex-4), a GLP1 receptor agonist, reduced oleate:palmitate-induced lipid accumulation and triglyceride content compared with cells without Ex-4 treatment. When we examined the oxygen consumption rate (OCR), not only the basal OCR but also the OCR induced by oleate:palmitate addition was significantly increased in Ex-4-treated differentiated C2C12 cells, and this was inhibited by exendin-9, a GLP1 receptor antagonist. The expression of uncoupling protein 1 (UCP1), ß3-adrenergic receptor, peroxisome proliferator-activator receptor a (PPARa) and farnesoid X receptor mRNA was significantly upregulated in Ex-4-treated differentiated C2C12 cells, and the upregulation of these mRNA was abolished by treatment with adenylate cyclase inhibitor (2'5'-dideoxyadenosine) or PKA inhibitor (H-89). As well, intramuscular injection of Ex-4 into diet-induced obese mice significantly increased the expression of UCP1, PPARa and p-AMPK in muscle. We suggest that exposure to GLP1 increases energy expenditure in muscle through the upregulation of fat oxidation and thermogenic gene expression, which may contribute to reducing obesity and insulin resistance.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Peptídeos/farmacologia , Termogênese/efeitos dos fármacos , Termogênese/genética , Peçonhas/farmacologia , Animais , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/genética , Exenatida , Ácidos Graxos/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Músculo Esquelético/metabolismo , PPAR alfa/metabolismo , Esterol Esterase/genética , Esterol Esterase/metabolismo , Proteína Desacopladora 1/metabolismo
11.
PLoS One ; 11(7): e0158796, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27391814

RESUMO

G protein-coupled receptor (GPR) 119 is expressed in pancreatic ß-cells and intestinal L cells, and is involved in glucose-stimulated insulin secretion and glucagon-like peptide-1 (GLP-1) release, respectively. Therefore, the development of GPR119 agonists is a potential treatment for type 2 diabetes. We screened 1500 natural plant extracts for GPR119 agonistic actions and investigated the most promising extract, that from Angelica dahurica (AD), for hypoglycemic actions in vitro and in vivo. Human GPR119 activation was measured in GeneBLAzer T-Rex GPR119-CRE-bla CHO-K1 cells; intracellular cAMP levels and insulin secretion were measured in INS-1 cells; and GLP-1 release was measured in GLUTag cells. Glucose tolerance tests and serum plasma insulin levels were measured in normal C57BL6 mice and diabetic db/db mice. AD extract-treated cells showed significant increases in GPR119 activation, intracellular cAMP levels, GLP-1 levels and glucose-stimulated insulin secretion as compared with controls. In normal mice, a single treatment with AD extract improved glucose tolerance and increased insulin secretion. Treatment with multiple doses of AD extract or n-hexane fraction improved glucose tolerance in diabetic db/db mice. Imperatorin, phellopterin and isoimperatorin were identified in the active fraction of AD extract. Among these, phellopterin activated GPR119 and increased active GLP-1 and insulin secretion in vitro and enhanced glucose tolerance in normal and db/db mice. We suggest that phellopterin might have a therapeutic potential for the treatment of type 2 diabetes.


Assuntos
Angelica/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Extratos Vegetais/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemia/genética , Hipoglicemia/metabolismo , Células L , Masculino , Camundongos , Extratos Vegetais/química , Ratos , Receptores Acoplados a Proteínas G/genética
12.
J Cell Physiol ; 231(8): 1822-31, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26661891

RESUMO

The expansion of autologous chondrocytes in vitro is used to generate sufficient populations for cell-based therapies. However, during monolayer culture, chondrocytes lose inherent characteristics and shift to fibroblast-like cells as passage number increase. Here, we investigated passage-dependent changes in cellular physiology, including cellular morphology, motility, and gene and protein expression, as well as the role of focal adhesion and cytoskeletal regulation in the dedifferentiation process. We found that the gene and protein expression levels of both the focal adhesion complex and small Rho GTPases are upregulated with increasing passage number and are closely linked to chondrocyte dedifferentiation. The inhibition of focal adhesion kinase (FAK) but not small Rho GTPases induced the loss of fibroblastic traits and the recovery of collagen type II, aggrecan, and SOX9 expression levels in dedifferentiated chondrocytes. Based on these findings, we propose a strategy to suppress chondrogenic dedifferentiation by inhibiting the identified FAK or Src pathways while maintaining the expansion capability of chondrocytes in a 2D environment. These results highlight a potential therapeutic target for the treatment of skeletal diseases and the generation of cartilage in tissue-engineering approaches. J. Cell. Physiol. 231: 1822-1831, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Desdiferenciação Celular , Condrócitos/patologia , Condrogênese , Adesões Focais/patologia , Agrecanas/metabolismo , Animais , Desdiferenciação Celular/efeitos dos fármacos , Proliferação de Células , Forma Celular , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrogênese/efeitos dos fármacos , Colágeno Tipo II/metabolismo , Quinase 1 de Adesão Focal/antagonistas & inibidores , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Adesões Focais/efeitos dos fármacos , Adesões Focais/metabolismo , Masculino , Fenótipo , Inibidores de Proteínas Quinases/farmacologia , Interferência de RNA , Ratos Sprague-Dawley , Fatores de Transcrição SOX9/metabolismo , Fatores de Tempo , Transfecção , Proteínas rho de Ligação ao GTP/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismo
13.
Sci Rep ; 5: 11851, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26138310

RESUMO

We report an observation of rapid (exceeding 2,000 K/s) heating of polydimethylsiloxane (PDMS), one of the most popular microchannel materials, under cyclic loadings at high (~MHz) frequencies. A microheater was developed based on the finding. The heating mechanism utilized vibration damping in PDMS induced by sound waves that were generated and precisely controlled using a conventional surface acoustic wave (SAW) microfluidic system. The refraction of SAW into the PDMS microchip, called the leaky SAW, takes a form of bulk wave and rapidly heats the microchannels in a volumetric manner. The penetration depths were measured to range from 210 µm to 1290 µm, enough to cover most sizes of microchannels. The energy conversion efficiency was SAW frequency-dependent and measured to be the highest at around 30 MHz. Independent actuation of each interdigital transducer (IDT) enabled independent manipulation of SAWs, permitting spatiotemporal control of temperature on the microchip. All the advantages of this microheater facilitated a two-step continuous flow polymerase chain reaction (CFPCR) to achieve the billion-fold amplification of a 134 bp DNA amplicon in less than 3 min.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...