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1.
Nanotechnology ; 35(24)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38461551

RESUMO

The sensor, designed to be worn directly on the skin, is suitable for real-time monitoring of the recovery level of not only general wounds, but also difficult-to-heal wounds, such as those with chronic inflammation. Notably, healthy skin has a pH range of 4-6. When a wound occurs, the pH is known to be approximately 7.4. In this study, alpha-naphtholphthalein (Naph) was immersed in a cotton-blended textile to produce a wearable halochromic sensor that clearly changed color depending on the pH of the skin in the range 6-9, including pH 7.4, which is the skin infection state. The coating was performed without using an organic solvent by dissolving it in micelle form using cetyltrimethylammonium bromide, a surfactant, in water. Naph-based halochromic sensor shows light yellow, which is the dye's own color, at pH 6, which is a healthy skin condition, and gradually showed a clear color change to light green-green-blue as pH increased. Even after washing and drying by rubbing with regular tap water, the color change due to pH was maintained more than 10 times. Naph-based halochromic sensors use a simple solution production and coating method and are not only reusable sensors that can be washed with water but also use environmentally friendly water, making them very suitable for developing commercial products for wound pH monitoring. In addition, it can be easily applied to medical supplies, such as medical gauze, patient clothes, and compression bandages, as well as everyday wear, such as clothing, gloves, and socks. Therefore, it is expected to be widely used as a wound pH sensor, allowing real-time monitoring of the skin condition of individuals with chronic skin inflammation, including patients requiring wound recovery.


Assuntos
Fenolftaleínas , Água , Dispositivos Eletrônicos Vestíveis , Humanos , Análise Custo-Benefício , Inflamação , Concentração de Íons de Hidrogênio
2.
Biochim Biophys Acta ; 1823(12): 2190-200, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22906541

RESUMO

Bax inhibitor-1 (BI-1), a member of the BI-1 family of integral membrane proteins, was originally identified as an inhibitor of stress-induced cell death in mammalian cells. Previous studies have shown that the withdrawal of leukemia inhibitory factor (LIF) results in differentiation of the majority of mouse embryonic stem (mES) cells into various cell lineages, while some ES cells die within 3days. Thus, to investigate the function of BI-1 in ES cell survival and neuronal differentiation, we generated mES cell lines that overexpress BI-1 or a carboxy-terminal BI-1ΔC mutant. Overexpression of BI-1 in mES cells significantly increased cell viability and resistance to apoptosis induced by LIF withdrawal, while the control vector or BI-1ΔC-overexpressing mES cells had no effect. Moreover, overexpression of BI-1 produced significant inhibition of the p38 mitogen-activated protein kinases (MAPK) pathway in response to LIF withdrawal, while activity of the extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinase (JNK) MAPK pathway was increased. Interestingly, we found that BI-1-overexpressing cells showed higher expression levels of neuroectodermal markers (Otx1, Lmx1b, En1, Pax2, Wnt1, Sox1, and Nestin) and greater neuronal differentiation efficiency than control or BI-1ΔC-overexpressing mES cells did. Considering these findings, our results indicated that BI-1-modulated MAPK activity plays a key role in protecting mES cells from LIF-withdrawal-induced apoptosis and in promoting their differentiation toward neuronal lineages.


Assuntos
Apoptose , Diferenciação Celular , Células-Tronco Embrionárias/citologia , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/citologia , Animais , Western Blotting , Proliferação de Células , Células-Tronco Embrionárias/metabolismo , Citometria de Fluxo , Técnicas Imunoenzimáticas , Fator Inibidor de Leucemia/genética , Fator Inibidor de Leucemia/metabolismo , Proteínas de Membrana/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Neurônios/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Biochim Biophys Acta ; 1823(4): 876-88, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22309999

RESUMO

Bax Inhibitor-1 (BI-1) is an evolutionally conserved apoptotic suppressor and belongs to the BI-1 family of proteins, which contain BI-1-like transmembrane domains. As their cellular functions and regulatory mechanisms remain incompletely understood, we compared their anti-apoptotic properties. Forced expression of BI-1 resulted in the most effective suppression of stress-induced apoptosis, compared with other family members, together with significant extracellular signal-regulated kinase (ERK)1/2 activation. BI-1-mediated ERK1/2 activation led to the suppression of mitochondria-mediated reactive oxygen species (ROS) production. Involvement of the ERK signaling pathway in BI-1-induced anti-apoptotic effects was confirmed by knockdown studies with ERK- or BI-1-specific siRNA. Moreover, we produced transgenic (TG) mice overexpressing BI-1, and the relationship between ERK1/2 activation and the suppression of ROS production or apoptosis was confirmed in mouse embryonic fibroblast (MEF) cells derived from these mice. Interestingly, we found that BI-1 TG mice showed splenomegaly and abnormal megakaryopoiesis. Taken together, our results suggest that BI-1-induced ERK1/2 activation plays an important role in the modulation of intracellular ROS generation and apoptotic cell death and may also affect autoimmune response.


Assuntos
Apoptose , Proteínas de Membrana/metabolismo , Mitocôndrias/enzimologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Esplenomegalia/enzimologia , Sequência de Aminoácidos , Animais , Apoptose/efeitos dos fármacos , Biologia Computacional , Citoproteção/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Etoposídeo/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/patologia , Células HEK293 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas de Membrana/química , Camundongos , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Dados de Sequência Molecular , Espécies Reativas de Oxigênio/metabolismo , Esplenomegalia/patologia , Estresse Fisiológico/efeitos dos fármacos
4.
Nat Commun ; 13(1): 1300, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288580

RESUMO

Although autophagy is critical for pancreatic ß-cell function, the role and mechanism of mitophagy in ß-cells are unclear. We studied the role of lysosomal Ca2+ in TFEB activation by mitochondrial or metabolic stress and that of TFEB-mediated mitophagy in ß-cell function. Mitochondrial or metabolic stress induced mitophagy through lysosomal Ca2+ release, increased cytosolic Ca2+ and TFEB activation. Lysosomal Ca2+ replenishment by ER- > lysosome Ca2+ refilling was essential for mitophagy. ß-cell-specific Tfeb knockout (TfebΔß-cell) abrogated high-fat diet (HFD)-induced mitophagy, accompanied by increased ROS and reduced mitochondrial cytochrome c oxidase activity or O2 consumption. TfebΔß-cell mice showed aggravation of HFD-induced glucose intolerance and impaired insulin release. Metabolic or mitochondrial stress induced TFEB-dependent expression of mitophagy receptors including Ndp52 and Optn, contributing to the increased mitophagy. These results suggest crucial roles of lysosomal Ca2+ release coupled with ER- > lysosome Ca2+ refilling and TFEB activation in mitophagy and maintenance of pancreatic ß-cell function during metabolic stress.


Assuntos
Lisossomos , Mitofagia , Animais , Autofagia/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Lisossomos/metabolismo , Camundongos , Mitocôndrias/metabolismo , Mitofagia/fisiologia , Estresse Fisiológico
5.
Cancer Imaging ; 21(1): 19, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531073

RESUMO

BACKGROUND: Radiomics is a promising field in oncology imaging. However, the implementation of radiomics clinically has been limited because its robustness remains unclear. Previous CT and PET studies suggested that radiomic features were sensitive to variations in pixel size and slice thickness of the images. The purpose of this study was to assess robustness of magnetic resonance (MR) radiomic features to pixel size resampling and interpolation in patients with cervical cancer. METHODS: This retrospective study included 254 patients with a pathological diagnosis of cervical cancer stages IB to IVA who received definitive chemoradiation at our institution between January 2006 and June 2020. Pretreatment MR scans were analyzed. Each region of cervical cancer was segmented on the axial gadolinium-enhanced T1- and T2-weighted images; 107 radiomic features were extracted. MR scans were interpolated and resampled using various slice thicknesses and pixel spaces. Intraclass correlation coefficients (ICCs) were calculated between the original images and images that underwent pixel size resampling (OP), interpolation (OI), or pixel size resampling and interpolation (OP+I) as well as among processed image sets with various pixel spaces (P), various slice thicknesses (I), and both (P + I). RESULTS: After feature standardization, ≥86.0% of features showed good robustness when compared between the original and processed images (OP, OI, and OP+I) and ≥ 88.8% of features showed good robustness when processed images were compared (P, I, and P + I). Although most first-order, shape, and texture features showed good robustness, GLSZM small-area emphasis-related features and NGTDM strength were sensitive to variations in pixel size and slice thickness. CONCLUSION: Most MR radiomic features in patients with cervical cancer were robust after pixel size resampling and interpolation following the feature standardization process. The understanding regarding the robustness of individual features after pixel size resampling and interpolation could help future radiomics research.


Assuntos
Imageamento por Ressonância Magnética/métodos , Radiometria/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
6.
Nat Commun ; 12(1): 183, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420039

RESUMO

We have reported that autophagy is crucial for clearance of amyloidogenic human IAPP (hIAPP) oligomer, suggesting that an autophagy enhancer could be a therapeutic modality against human diabetes with amyloid accumulation. Here, we show that a recently identified autophagy enhancer (MSL-7) reduces hIAPP oligomer accumulation in human induced pluripotent stem cell-derived ß-cells (hiPSC-ß-cells) and diminishes oligomer-mediated apoptosis of ß-cells. Protective effects of MSL-7 against hIAPP oligomer accumulation and hIAPP oligomer-mediated ß-cell death are significantly reduced in cells with knockout of MiTF/TFE family members such as Tfeb or Tfe3. MSL-7 improves glucose tolerance and ß-cell function of hIAPP+ mice on high-fat diet, accompanied by reduced hIAPP oligomer/amyloid accumulation and ß-cell apoptosis. Protective effects of MSL-7 against hIAPP oligomer-mediated ß-cell death and the development of diabetes are also significantly reduced by ß-cell-specific knockout of Tfeb. These results suggest that an autophagy enhancer could have therapeutic potential against human diabetes characterized by islet amyloid accumulation.


Assuntos
Amiloide/metabolismo , Proteínas Amiloidogênicas/metabolismo , Autofagia/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/genética , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Animais , Apoptose/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Técnicas de Inativação de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Secretoras de Insulina , Macroautofagia/fisiologia , Camundongos , Camundongos Transgênicos
7.
Artigo em Inglês | MEDLINE | ID: mdl-33255478

RESUMO

Background: Firefighters are vulnerable to irregular sleep patterns and sleep disturbance due to work characteristics such as shift work and frequent dispatch. However, there are few studies investigating intervention targeting sleep for firefighters. This preliminary study aimed to develop and test a sleep intervention, namely FIT-IN (Firefighter's Therapy for Insomnia and Nightmares), which was based on existing evidence-based treatment tailored to firefighters in consideration of their occupational characteristics. Methods: This study implemented a single-group pre-post study design, utilizing an intervention developed based on brief behavior therapy for insomnia with imagery rehearsal therapy components. FIT-IN consisted of a total of three sessions (two face-to-face group sessions and one telephone session). Participants were recruited from Korean fire stations, and a total of 39 firefighters participated. Participants completed a sleep diary for two weeks, as well as the following questionnaires to assess their sleep and psychological factors: insomnia severity index (ISI), disturbing dream and nightmare severity index (DDNSI), Epworth sleepiness scale (ESS), depressive symptom inventory-suicidality subscale (DSI), and Patient Health Questionnaire-9 (PHQ-9). These questionnaires were administered before the first session and at the end of the second session. Results: The FIT-IN program produced improvements in sleep indices. There was a significant increase in sleep efficiency (p < 0.01), and a decrease in sleep onset latency, number of awakenings, and time in bed (p < 0.05), as derived from weekly sleep diaries. In addition, significant decreases were shown for insomnia (p < 0.001) and nightmare severity (p < 0.01). Conclusion: There were significant improvements in sleep and other clinical indices (depression, PTSD scores) when comparing pre-and post-intervention scores. FIT-IN may be a feasible and practical option in alleviating sleep disturbance in this population. Further studies will be needed to ascertain FIT-IN's effectiveness.


Assuntos
Terapia Cognitivo-Comportamental , Bombeiros , Distúrbios do Início e da Manutenção do Sono , Sonhos , Feminino , Humanos , Masculino , Sono , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
8.
Cell Stress ; 2(7): 181-183, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31225485

RESUMO

Autophagy insufficiency due to aging, high-fat injury or genetic predisposition could be a factor in the progression of metabolic syndrome and diabetes. On the other hand, autophagy enhancement may have beneficial metabolic impact on in vivo metabolism of obese subjects. To identify novel, autophagy enhancer small molecules, we screened a chemical library using a Renilla-LC3-based luciferase assay [Lim et al. Nat Commun 9:1438]. Of the >7000 tested substances, one chemical compound, termed MSL (4-(4-fluorophenyl)sulfonyl-5-methylthio-2-phenyloxazole), (i) enhanced autophagic activity through Tfeb activation, (ii) expedited lipid clearance, probably through lipophagy, and (iii) reduced inflammasome activation through amelioration of mitochondrial dysfunction both in vitro and in vivo, leading to improved metabolic profile of mice with genetic or diet-induced obesity.

9.
Nat Commun ; 9(1): 1438, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650965

RESUMO

Autophagy is a critical regulator of cellular homeostasis, dysregulation of which is associated with diverse diseases. Here we show therapeutic effects of a novel autophagy enhancer identified by high-throughput screening of a chemical library against metabolic syndrome. An autophagy enhancer increases LC3-I to LC3-II conversion without mTOR inhibition. MSL, an autophagy enhancer, activates calcineurin, and induces dephosphorylation/nuclear translocation of transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy gene expression. MSL accelerates intracellular lipid clearance, which is reversed by lalistat 2 or Tfeb knockout. Its administration improves the metabolic profile of ob/ob mice and ameliorates inflammasome activation. A chemically modified MSL with increased microsomal stability improves the glucose profile not only of ob/ob mice but also of mice with diet-induced obesity. Our data indicate that our novel autophagy enhancer could be a new drug candidate for diabetes or metabolic syndrome with lipid overload.


Assuntos
Autofagia/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Oxazóis/uso terapêutico , Animais , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Células HeLa , Humanos , Hipoglicemiantes/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Síndrome Metabólica/metabolismo , Síndrome Metabólica/patologia , Metaboloma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Oxazóis/química , Estresse Fisiológico/efeitos dos fármacos
10.
Arch Pharm Res ; 40(3): 382-390, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27864660

RESUMO

Celecoxib, a selective cyclooxygenase (COX)-2 inhibitor, is used for the treatment of rheumatoid arthritis and osteoarthritis. The predominant hepatic metabolism of celecoxib to celecoxib carboxylic acid (CCA) is mediated mainly by CYP2C9. We investigated the effects of the major CYP2C9 genetic variants in Asian populations, CYP2C9*3 and CYP2C9*13, on the pharmacokinetics of celecoxib and its carboxylic acid metabolite in healthy Korean subjects. A single 200-mg oral dose of celecoxib was given to 52 Korean subjects with different CYP2C9 genotypes: CYP2C9EM (n = 26; CYP2C9*1/*1), CYP2C9IM (n = 24; CYP2C9*1/*3 and *1/*13), and CYP2C9PM (n = 2; CYP2C9*3/*3). Celecoxib and CCA concentrations in plasma samples collected up to 48 or 96 h after drug intake were determined by HPLC-MS/MS. The mean area under the plasma concentration-time curve (AUC0-∞) of celecoxib was increased 1.63-fold (P < 0.001), and the apparent oral clearance (CL/F) of celecoxib was decreased by 39.6% in the CYP2C9IM genotype group compared with that of CYP2C9EM (P < 0.001). The overall pharmacokinetic parameters for celecoxib in CYP2C9*1/*13 subjects were similar to those in CYP2C9*1/*3 subjects. Two subjects with CYP2C9PM genotype both showed markedly higher AUC0-∞, prolonged half-life, and lower CL/F for celecoxib than did subjects with CYP2C9EM and IM genotypes. CYP2C9*3 and CYP2C9*13 variant alleles significantly affected the plasma concentration of celecoxib.


Assuntos
Celecoxib/farmacocinética , Inibidores de Ciclo-Oxigenase 2/farmacocinética , Citocromo P-450 CYP2C9/genética , Citocromo P-450 CYP2C9/metabolismo , Alelos , Povo Asiático/genética , Ácidos Carboxílicos/metabolismo , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Polimorfismo Genético , Adulto Jovem
11.
IMA Fungus ; 8(2): 385-396, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29242781

RESUMO

The genomes of Cercospora zeina, Fusarium pininemorale, Hawksworthiomyces lignivorus, Huntiella decipiens, and Ophiostoma ips are presented in this genome announcement. Three of these genomes are from plant pathogens and otherwise economically important fungal species. Fusarium pininemorale and H. decipiens are not known to cause significant disease but are closely related to species of economic importance. The genome sizes range from 25.99 Mb in the case of O. ips to 4.82 Mb for H. lignivorus. These genomes include the first reports of a genome from the genus Hawksworthiomyces. The availability of these genome data will allow the resolution of longstanding questions regarding the taxonomy of these species. In addition these genome sequences through comparative studies with closely related organisms will increase our understanding of how these species or close relatives cause disease.

12.
Biomed Mater ; 11(5): 055003, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27586647

RESUMO

During cell differentiation for tissue regeneration, several factors, including growth factors and proteins, influence cascades in stem cells such as embryonic stem cells and mesenchymal stem cells (MSCs). In this study, transforming growth factor (TGF)-ß3 and SOX9, which is an important protein in chondrocytes, were used to generate mature chondrocytes from human MSCs (hMSCs). For safe and effective delivery of bioactive molecules into hMSCs, biodegradable poly-(d,l-lactide-co-glycolide) (PLGA) microspheres (MSs) were coated with TGF-ß3 and loaded with SOX9. Instead of SOX9 protein, release of the model protein FITC-bovine serum albumin (BSA) from PLGA MS was evaluated in vitro and in vivo by confocal laser microscopy and Kodak imaging. The bioactivities of TGF-ß3 and SOX9 were evaluated by assessing α-helical formation using circular dichroism. PLGA MS loaded with FITC-BSA easily entered hMSCs without causing cytotoxicity. To confirm that internalization of PLGA MSs harboring TGF-ß3 and SOX9 induced chondrogenesis of hMSCs, we performed several molecular analyses. By analysis, the specific marker gene expression levels in hMSCs adhered onto PLGA MSs coated with TGF-ß3 and loaded with SOX9 were more than 3-5 times that of the control group both in vitro and in vivo. This result revealed that PLGA MS uptake and subsequent release of SOX9 induced chondrogenesis of hMSCs was enhanced by coating PLGA MSs with TGF-ß3.


Assuntos
Condrogênese , Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Células-Tronco/citologia , Alicerces Teciduais/química , Animais , Cartilagem , Diferenciação Celular , Células Cultivadas , Condrócitos/citologia , Dicroísmo Circular , Feminino , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Regeneração , Fatores de Transcrição SOX9/metabolismo , Soroalbumina Bovina/química , Células-Tronco/metabolismo , Fator de Crescimento Transformador beta3/metabolismo
13.
Health Soc Work ; 40(1): 26-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25665288

RESUMO

The purpose of the study reported in this article was to investigate the relationship between employment status and self-rated health (SRH) and the moderating effect of household income among wage workers in South Korea. This research analyzed the Korean Labor and Income Panel Study, 2005 to 2008. Of the 10,494 respondents participating in the survey during the period, a total of 1,548 people whose employment status had remained either precarious or nonprecarious were selected. A moderated multiple regression model was used to examine the main effect of employment status on SRH and the moderating effect of total household income on the relationship between employment status and SRH. Among 343 precarious workers and 1,205 nonprecarious workers, after controlling for gender, age, education, smoking, and drinking, employment status was associated with SRH of wage workers, and household income was found to have a moderating effect on SRH in that higher income buffers the link between unstable employment status and low SRH. Unstable employment, combined with low income, was significantly related to precarious wage workers' perceived health. To promote public health, efforts may be needed to secure not only people's employment, but also their income.


Assuntos
Emprego/estatística & dados numéricos , Indicadores Básicos de Saúde , Renda/estatística & dados numéricos , Incerteza , Adulto , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , República da Coreia , Inquéritos e Questionários
14.
Nat Commun ; 5: 4934, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25255859

RESUMO

Despite growing interest in the relationship between autophagy and systemic metabolism, how global changes in autophagy affect metabolism remains unclear. Here we show that mice with global haploinsufficiency of an essential autophagy gene (Atg7(+/-) mice) do not show metabolic abnormalities but develop diabetes when crossed with ob/ob mice. Atg7(+/-)-ob/ob mice show aggravated insulin resistance with increased lipid content and inflammatory changes, suggesting that autophagy haploinsufficiency impairs the adaptive response to metabolic stress. We further demonstrate that intracellular lipid content and insulin resistance after lipid loading are increased as a result of autophagy insufficiency, and provide evidence for increased inflammasome activation in Atg7(+/-)-ob/ob mice. Imatinib or trehalose improves metabolic parameters of Atg7(+/-)-ob/ob mice and enhances autophagic flux. These results suggest that systemic autophagy insufficiency could be a factor in the progression from obesity to diabetes, and autophagy modulators have therapeutic potential against diabetes associated with obesity and inflammation.


Assuntos
Autofagia , Diabetes Mellitus/fisiopatologia , Obesidade/fisiopatologia , Adaptação Fisiológica , Animais , Diabetes Mellitus/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/patologia , Estresse Fisiológico
15.
Arch Pharm Res ; 35(2): 245-60, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22370779

RESUMO

Discovery of induced pluripotent stem (iPS) cells in 2006 provided a new path for cell transplantation and drug screening. The iPS cells are stem cells derived from somatic cells that have been genetically reprogrammed into a pluripotent state. Similar to embryonic stem (ES) cells, iPS cells are capable of differentiating into three germ layers, eliminating some of the hurdles in ES cell technology. Further progress and advances in iPS cell technology, from viral to non-viral systems and from integrating to non-integrating approaches of foreign genes into the host genome, have enhanced the existing technology, making it more feasible for clinical applications. In particular, advances in iPS cell technology should enable autologous transplantation and more efficient drug discovery. Cell transplantation may lead to improved treatments for various diseases, including neurological, endocrine, and hepatic diseases. In studies on drug discovery, iPS cells generated from patient-derived somatic cells could be differentiated into specific cells expressing specific phenotypes, which could then be used as disease models. Thus, iPS cells can be helpful in understanding the mechanisms of disease progression and in cell-based efficient drug screening. Here, we summarize the history and progress of iPS cell technology, provide support for the growing interest in iPS cell applications with emphasis on practical uses in cell-based drug screening, and discuss some challenges faced in the use of this technology.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Animais , Diferenciação Celular , Humanos , Modelos Biológicos , Transplante de Células-Tronco/métodos
16.
Biomaterials ; 33(21): 5206-20, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22541355

RESUMO

Embryonic stem (ES) cells can undergo continual proliferation and differentiation into cells of all somatic cell lineages in vitro; they are an unlimited cell source for regenerative medicine. However, techniques for maintaining undifferentiated ES cells are often inefficient and result in heterogeneous cell populations. Here, we determined effects of nanopattern polydimethylsiloxane (PDMS) as a culture substrate in promoting the self-renewal of mouse ES (mES) cells, compared to commercial plastic culture dishes. After many passages, mES cells efficiently maintained their undifferentiated state on nanopattern PDMS, but randomly differentiated on commercial plastic culture dishes, as indicated by partially altered morphologies and decreases in alkaline phosphatase activity and stage-specific expression of embryonic antigen-1. Under nanopattern PDMS conditions, we found increased activities of STAT3 and Akt, important proteins involved in maintaining the self-renewal of mES cells. The substrate-cell interactions also enhanced leukemia inhibitory factor (LIF)-downstream signaling and inhibited spontaneous differentiation, concomitant with reduced focal adhesion kinase (FAK) signaling. This reduction in FAK signaling was shown to be important for promoting mES cell self-renewal. Thus, our data demonstrates that nanopattern PDMS contributes to maintaining the self-renewal of mES cells and may be applicable in the large-scale production of homogeneously undifferentiated mES cells.


Assuntos
Técnicas de Cultura de Células/métodos , Dimetilpolisiloxanos/farmacologia , Células-Tronco Embrionárias/citologia , Nanopartículas/química , Animais , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/enzimologia , Células-Tronco Embrionárias/ultraestrutura , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Adesões Focais/efeitos dos fármacos , Adesões Focais/metabolismo , Fator Inibidor de Leucemia/metabolismo , Camundongos , Nanopartículas/ultraestrutura , Propriedades de Superfície/efeitos dos fármacos
17.
Stem Cells Dev ; 21(14): 2642-55, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22512788

RESUMO

The nonobese diabetic (NOD) mouse is a classical animal model for autoimmune type 1 diabetes (T1D), closely mimicking features of human T1D. Thus, the NOD mouse presents an opportunity to test the effectiveness of induced pluripotent stem cells (iPSCs) as a therapeutic modality for T1D. Here, we demonstrate a proof of concept for cellular therapy using NOD mouse-derived iPSCs (NOD-iPSCs). We generated iPSCs from NOD mouse embryonic fibroblasts or NOD mouse pancreas-derived epithelial cells (NPEs), and applied directed differentiation protocols to differentiate the NOD-iPSCs toward functional pancreatic beta cells. Finally, we investigated whether the NPE-iPSC-derived insulin-producing cells could normalize hyperglycemia in transplanted diabetic mice. The NOD-iPSCs showed typical embryonic stem cell-like characteristics such as expression of markers for pluripotency, in vitro differentiation, teratoma formation, and generation of chimeric mice. We developed a method for stepwise differentiation of NOD-iPSCs into insulin-producing cells, and found that NPE-iPSCs differentiate more readily into insulin-producing cells. The differentiated NPE-iPSCs expressed diverse pancreatic beta cell markers and released insulin in response to glucose and KCl stimulation. Transplantation of the differentiated NPE-iPSCs into diabetic mice resulted in kidney engraftment. The engrafted cells responded to glucose by secreting insulin, thereby normalizing blood glucose levels. We propose that NOD-iPSCs will provide a useful tool for investigating genetic susceptibility to autoimmune diseases and generating a cellular interaction model of T1D, paving the way for the potential application of patient-derived iPSCs in autologous beta cell transplantation for treating diabetes.


Assuntos
Diferenciação Celular , Diabetes Mellitus Experimental/terapia , Células-Tronco Pluripotentes Induzidas/citologia , Células Secretoras de Insulina/transplante , Animais , Biomarcadores/metabolismo , Glicemia , Quimera/genética , Quimera/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Camadas Germinativas/citologia , Camadas Germinativas/metabolismo , Glucose/farmacologia , Hiperglicemia/terapia , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Endogâmicos NOD , Camundongos SCID , Cloreto de Potássio/farmacologia , Estreptozocina , Teratoma/metabolismo
18.
Biomaterials ; 32(28): 6683-91, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21683440

RESUMO

Induced pluripotent stem (iPS) cells have been generated from various somatic cells; however, a major restriction of the technology is the use of potentially harmful genome-integrating viral DNAs. Here, without a viral vector, we generated iPS cells from fibroblasts using a non-viral magnetic nanoparticle-based transfection method that employs biodegradable cationic polymer PEI-coated super paramagnetic nanoparticles (NP). Our findings support the possible use of transient expression of iPS genes in somatic cells by magnet-based nanofection for efficient generation of iPS cells. Results of dynamic light scattering (DLS) analysis and TEM analyses demonstrated efficient conjugation of NP with iPS genes. After transfection, nanofection-mediated iPS cells showed ES cell-like characteristics, including expression of endogenous pluripotency genes, differentiation of three germ layer lineages, and formation of teratomas. Our results demonstrate that magnet-based nanofection may provide a safe method for use in generation of virus-free and exogenous DNA-free iPS cells, which will be crucial for future clinical applications in the field of regenerative medicine.


Assuntos
Células-Tronco Pluripotentes Induzidas/fisiologia , Magnetismo/métodos , Nanopartículas Metálicas/química , Transfecção/métodos , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL
19.
J Colloid Interface Sci ; 241(1): 269-274, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11502129

RESUMO

A novel aqueous fluorine-containing polyurethane was prepared with a hydrophobic macromonomer of a perfluoroalkyl group. Two representative properties of the polyurethane, initial particle diameter dispersed in water and surface free energy of coating films, were investigated. The macromonomer was synthesized by radical copolymerization of perfluoroalkylethyl acrylate and methyl methacrylate with a diol of chain-transfer agent in order to attenuate solubility and hydrophobic property. Anionic aqueous polyurethane was obtained with a good hydrophobic film property by one-step condensation polymerization of the macromonomer with hydrophilic comonomers and successive ionization. The polyurethane showed an initial average diameter of less than 1100 nm in water and surface free energies of less than 19 dyn/cm. The water dispersion property and hydrophobic surface property of the polyurethane can be controlled by controlling the content and hydrophobic property of the macromonomer. The incorporation of the macromonomer in the polyurethane backbone did not show a significant effect on the glass transition temperature, or the softness, of the polyurethane. Copyright 2001 Academic Press.

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