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1.
Biotechnol Bioeng ; 120(5): 1241-1253, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36639871

RESUMO

Hepatic stellate cells (HSCs) play an important role in liver fibrosis; however, owing to the heterogeneity and limited supply of primary HSCs, the development of in vitro liver fibrosis models has been impeded. In this study, we established and characterized a novel human HSC line (LSC-1), and applied it to various types of three-dimensional (3D) co-culture systems with differentiated HepaRG cells. Furthermore, we compared LSC-1 with a commercially available HSC line on conventional monolayer culture. LSC-1 exhibited an overall upregulation of the expression of fibrogenic genes along with increased levels of matrix and adhesion proteins, suggesting a myofibroblast-like or transdifferentiated state. However, activated states reverted to a quiescent-like phenotype when cultured in different 3D culture formats with a relatively soft microenvironment. Additionally, LSC-1 exerted an overall positive effect on co-cultured differentiated HepaRG, which significantly increased hepatic functionality upon long-term cultivation compared with that achieved with other HSC line. In 3D spheroid culture, LSC-1 exhibited enhanced responsiveness to transforming growth factor beta 1 exposure that is caused by a different matrix-related protein expression mechanism. Therefore, the LSC-1 line developed in this study provides a reliable candidate model that can be used to address unmet needs, such as development of antifibrotic therapies.


Assuntos
Células Estreladas do Fígado , Cirrose Hepática , Humanos , Células Estreladas do Fígado/metabolismo , Técnicas de Cocultura , Cirrose Hepática/metabolismo , Fígado/metabolismo , Linhagem Celular
2.
J Org Chem ; 86(11): 7390-7402, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34028267

RESUMO

Herein, we describe the direct synthesis of pyrrolo[1,2-α]quinoxaline via oxidative coupling between methyl arene and 1-(2-aminophenyl) pyrroles. Oxidation of the benzylic carbon of the methyl arene was achieved by di-t-butyl peroxide in the presence of an iron catalyst, followed by conversion to an activated aldehyde in situ. Oxygen played a crucial role in the oxidation process to accelerate benzaldehyde formation. Subsequent Pictet-Spengler-type annulation completed the quinoxaline structure. The protocol tolerated various kinds of functional groups and provided 22 4-aryl pyrrolo[1,2-α]quinoxalines when various methyl arene derivatives were used. The developed method proceeded in air, and all catalysts, reagents, and solvents were easily accessible.


Assuntos
Ferro , Quinoxalinas , Catálise , Estrutura Molecular , Acoplamento Oxidativo
3.
Anal Chem ; 92(18): 12152-12159, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32786445

RESUMO

Interference is a pivotal issue of a non-dispersive infrared (NDIR) sensor and analyzer. Therefore, the main contribution of this study is to introduce a potential method to compensate for the interference of the NDIR analysis. A potential method to compensate for the interference of a nitric oxide (NO) NDIR analyzer was developed. Double bandpass filters (BPFs) with HITRAN (high-resolution transmission molecular absorption database)-based wavelengths were used to create an ultranarrow bandwidth, where there were least-interfering effects with respect to the coal-fired power plant emission gas compositions. Key emission gases from a coal-fired power plant, comprising carbon monoxide (CO), NO, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon dioxide (CO2), and water (H2O) (in the form of vapor), were used to investigate the gas interference. The mixtures of those gases were also used to investigate the performance of the double BPFs. We found that CO, CO2, SO2, and H2O significantly affected the detection of NO when a commercial, single narrow BPF was used. In contrast, the double BPFs could remove the interference of CO, NO2, SO2, and CO2 in terms of their concentrations. In the case of H2O, the filter performed well until a level of 50% relative humidity at 25 °C. Moreover, the signal-to-noise ratio of the analyzer was approximately 10 when the double BPFs were applied. In addition, the limit of detection of the analyzer with the double BPFs was approximately 4 ppm, whereas that with the commercial one was 1.3 ppm. Therefore, double BPFs could be used for an NO NDIR analyzer instead of a gas filter correlation to improve the selectivity of the analyzer under the condition of a known gas composition, such as a coal-fired power plant. However, the sensitivity of the analyzer would be decreased.

4.
Biotechnol Bioeng ; 117(6): 1864-1876, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32162676

RESUMO

Although primary human hepatocytes (PHHs) are the gold standard in drug efficacy and metabolism studies, long-term survival of PHHs and maintenance of their hepatic function are still challenging. In this study, we focused on the effect of the initial microenvironment on upregulation and long-term preservation of hepatic function of PHHs encapsulated within biodegradable hydrogel systems. PHHs were encapsulated in RGD-functionalized hybrid hydrogels with various degrees of degradability, and their hepatic functionality was analyzed. Regardless of the hydrogel elastic modulus, the combination with nondegradable hydrogels had a predominantly negative effect on the prompt engraftment of PHHs, whereas a degradable hydrogel with intermediate initial degradability was most effective in maintaining hepatic function. Efficient network formation by PHHs and cocultured cells, along with the control of hydrogel degradation, governed the hepatic functionality at an early stage and upon long-term cultivation. Under optimized conditions, expression of genes involved in biological processes such as focal adhesions, cell survival, cytoskeleton formation, and extracellular matrix interactions was significantly higher than that in a control with relatively delayed initial degradation. Thus, we suggest that the orchestrated control of initial cellular remodeling may play an important role in the maintenance of hepatic function in a three-dimensional PHH culture.


Assuntos
Materiais Biocompatíveis/química , Células Imobilizadas/citologia , Hepatócitos/citologia , Hidrogéis/química , Técnicas de Cultura de Células/métodos , Linhagem Celular , Células Cultivadas , Células Imobilizadas/metabolismo , Módulo de Elasticidade , Expressão Gênica , Hepatócitos/metabolismo , Humanos , Alicerces Teciduais/química
5.
J Org Chem ; 85(23): 15314-15324, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33119283

RESUMO

Herein, we describe novel iron-catalyzed transfer hydrogenation between alcohols and 1-(2-nitrophenyl)pyrroles for the synthesis of pyrrolo[1,2-α]quinoxalines. The tricarbonyl (η4-cyclopentadienone) iron complex catalyzed the oxidation of alcohols and the reduction of nitroarenes, and the corresponding aldehydes and aniline were generated in situ. The resulting Pictet-Spengler-type annulation/oxidation completed the quinoxaline structure formation. The protocol tolerated various kinds of functional groups and provided 29 samples of 4-substituted pyrrolo[1,2-α]quinoxalines. The developed method was also applied for the synthesis of additional polyheterocycles.

6.
Int J Mol Sci ; 21(12)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549364

RESUMO

Our previous studies demonstrated that peroxisome proliferator-activated receptor α (PPARα) activation reduces weight gain and improves insulin sensitivity in obese mice. Since excess lipid accumulation in non-adipose tissues is suggested to be responsible for the development of insulin resistance, this study was undertaken to examine whether the lemon balm extract ALS-L1023 regulates hepatic lipid accumulation, obesity, and insulin resistance and to determine whether its mechanism of action involves PPARα. Administration of ALS-L1023 to high-fat-diet-induced obese mice caused reductions in body weight gain, visceral fat mass, and visceral adipocyte size without changes of food consumption profiles. ALS-L1023 improved hyperglycemia, hyperinsulinemia, glucose and insulin tolerance, and normalized insulin-positive ß-cell area in obese mice. ALS-L1023 decreased hepatic lipid accumulation and concomitantly increased the expression of PPARα target genes responsible for fatty acid ß-oxidation in livers. In accordance with the in vivo data, ALS-L1023 reduced lipid accumulation and stimulated PPARα reporter gene expression in HepG2 cells. These effects of ALS-L1023 were comparable to those of the PPARα ligand fenofibrate, while the PPARα antagonist GW6471 inhibited the actions of ALS-L1023 on lipid accumulation and PPARα luciferase activity in HepG2 cells. Higher phosphorylated protein kinase B (pAkt)/Akt ratios and lower expression of gluconeogenesis genes were observed in the livers of ALS-L1023-treated mice. These results indicate that ALS-L1023 may inhibit obesity and improve insulin sensitivity in part through inhibition of hepatic lipid accumulation via hepatic PPARα activation.


Assuntos
Resistência à Insulina/genética , Fígado/metabolismo , Obesidade/tratamento farmacológico , PPAR alfa/genética , Extratos Vegetais/administração & dosagem , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Animais , Tamanho Celular/efeitos dos fármacos , Dieta Hiperlipídica , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Obesidade/induzido quimicamente , Obesidade/genética , Obesidade/metabolismo , PPAR alfa/metabolismo , Fosforilação/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
7.
Cancer Sci ; 110(4): 1453-1463, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30729615

RESUMO

Tumor cells overexpress amino acid transporters to meet the increased demand for amino acids. PQ loop repeat-containing (PQLC)2 is a cationic amino acid transporter that might be involved in cancer progression. Here, we show that upregulation of PQLC2 is critical to gastric cancer (GC) development in vitro and in vivo. Both PQLC2 mRNA and protein were overexpressed in GC tissues, especially of the diffuse type. Overexpression of PQLC2 promoted cell growth, anchorage independence, and tumor formation in nude mice. This was due to activation of MEK/ERK1/2 and PI3K/AKT signaling. Conversely, PQLC2 knockdown caused growth arrest and cell death of cancer cells and suppressed tumor growth in a mouse xenograft model. These results suggest that targeting PQLC2 is an effective strategy for GC treatment.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Neoplasias Gástricas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Sistemas de Transporte de Aminoácidos Básicos/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Modelos Animais de Doenças , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Int J Obes (Lond) ; 43(8): 1620-1630, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30283077

RESUMO

BACKGROUND/OBJECTIVES: Ascorbic acid is a known cofactor in the biosynthesis of carnitine, a molecule that has an obligatory role in fatty acid oxidation. Our previous studies have demonstrated that obesity is regulated effectively through peroxisome proliferator-activated receptor α (PPARα)-mediated fatty acid ß-oxidation. Thus, this study aimed to determine whether ascorbic acid can inhibit obesity and nonalcoholic fatty liver disease (NAFLD) in part through the actions of PPARα. DESIGN: After C57BL/6J mice received a low-fat diet (LFD, 10% kcal fat), a high-fat diet (HFD, 45% kcal fat), or the same HFD supplemented with ascorbic acid (1% w/w) (HFD-AA) for 15 weeks, variables and determinants of visceral obesity and NAFLD were examined using metabolic measurements, histology, and gene expression. RESULTS: Compared to HFD-fed obese mice, administration of HFD-AA to obese mice reduced body weight gain, visceral adipose tissue mass, and visceral adipocyte size without affecting food consumption profiles. Concomitantly, circulating ascorbic acid concentrations were significantly higher in HFD-AA mice than in HFD mice. Ascorbic acid supplementation increased the mRNA levels of PPARα and its target enzymes involved in fatty acid ß-oxidation in visceral adipose tissues. Consistent with the effects of ascorbic acid on visceral obesity, ascorbic acid not only inhibited hepatic steatosis but also increased the mRNA levels of PPARα-dependent fatty acid ß-oxidation genes in livers. Similarly, hepatic inflammation, fibrosis, and apoptosis were also decreased during ascorbic acid-induced inhibition of visceral obesity. In addition, serum levels of alanine aminotransferase, aspartate aminotransferase, total cholesterol, and LDL cholesterol were lower in HFD-AA-fed mice than in those of HFD-fed mice. CONCLUSIONS: These results suggest that ascorbic acid seems to suppress HFD-induced visceral obesity and NAFLD in part through the activation of PPARα.


Assuntos
Ácido Ascórbico/farmacologia , Dieta Hiperlipídica , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade Abdominal/metabolismo , PPAR alfa/metabolismo , Animais , Ácido Ascórbico/antagonistas & inibidores , Dieta com Restrição de Gorduras , Suplementos Nutricionais , Ácidos Graxos/metabolismo , Expressão Gênica , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade Abdominal/genética , Oxirredução/efeitos dos fármacos , PPAR alfa/genética , Aumento de Peso/efeitos dos fármacos
9.
Biotechnol Bioeng ; 116(6): 1496-1508, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30737956

RESUMO

Spheroids, a widely used three-dimensional (3D) culture model, are standard in hepatocyte culture as they preserve long-term hepatocyte functionality and enhance survivability. In this study, we investigated the effects of three operation modes in 3D culture - static, orbital shaking, and under vertical bidirectional flow using spheroid forming units (SFUs) on hepatic differentiation and drug metabolism to propose the best for mass production of functionally enhanced spheroids. Spheroids in SFUs exhibited increased hepatic gene expression, albumin secretion, and cytochrome P450 3A4 (CYP3A4) activity during the differentiation period (12 days). SFUs advantages include facilitated mass production and a relatively earlier peak of CYP3A4 activity. However, CYP3A4 activity was not well maintained under dimethyl sulfoxide (DMSO)-free conditions (13-18 days), dramatically reducing drug metabolism capability. Continued shear stimulation without differentiation stimuli in assay conditions markedly attenuated CYP3A4 activity, which was less severe in static conditions. In this condition, SFU spheroids exhibited dedifferentiation characteristics, such as increased proliferation and Notch signaling genes. We found that the dedifferentiation could be overcome by using the serum-free medium formulation. Therefore, we suggest that SFUs represent the best option for the mass production of functionally improved spheroids and so the serum-free conditions should be maintained during drug metabolism analysis.


Assuntos
Técnicas de Cultura de Células/instrumentação , Hepatócitos/metabolismo , Preparações Farmacêuticas/metabolismo , Esferoides Celulares/metabolismo , Albuminas/metabolismo , Linhagem Celular , Citocromo P-450 CYP3A/metabolismo , Desenho de Equipamento , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Humanos , Esferoides Celulares/efeitos dos fármacos
10.
Hepatology ; 66(5): 1662-1674, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28640507

RESUMO

Alternative cell sources, such as three-dimensional organoids and induced pluripotent stem cell-derived cells, might provide a potentially effective approach for both drug development applications and clinical transplantation. For example, the development of cell sources for liver cell-based therapy has been increasingly needed, and liver transplantation is performed for the treatment for patients with severe end-stage liver disease. Differentiated liver cells and three-dimensional organoids are expected to provide new cell sources for tissue models and revolutionary clinical therapies. However, conventional experimental methods confirming the expression levels of liver-specific lineage markers cannot provide complete information regarding the differentiation status or degree of similarity between liver and differentiated cell sources. Therefore, in this study, to overcome several issues associated with the assessment of differentiated liver cells and organoids, we developed a liver-specific gene expression panel (LiGEP) algorithm that presents the degree of liver similarity as a "percentage." We demonstrated that the percentage calculated using the LiGEP algorithm was correlated with the developmental stages of in vivo liver tissues in mice, suggesting that LiGEP can correctly predict developmental stages. Moreover, three-dimensional cultured HepaRG cells and human pluripotent stem cell-derived hepatocyte-like cells showed liver similarity scores of 59.14% and 32%, respectively, although general liver-specific markers were detected. CONCLUSION: Our study describes a quantitative and predictive model for differentiated samples, particularly liver-specific cells or organoids; and this model can be further expanded to various tissue-specific organoids; our LiGEP can provide useful information and insights regarding the differentiation status of in vitro liver models. (Hepatology 2017;66:1662-1674).


Assuntos
Diferenciação Celular , Hepatócitos/metabolismo , Algoritmos , Técnicas de Cultura de Células , Células Hep G2 , Hepatócitos/citologia , Humanos , Análise de Sequência de RNA
11.
Biochim Biophys Acta ; 1863(11): 2584-2593, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27452907

RESUMO

Shikonin derivatives exert powerful cytotoxic effects including induction of apoptosis. Here, we demonstrate the cytotoxic efficacy of shikonin in vivo in xenograft models, which did not affect body weight as well as its reduction of cell viability in vitro using several non-small cell lung cancer (NSCLC) cell lines. We found that inhibition of AKT by shikonin activated the forkhead box (FOX)O3a/early growth response protein (EGR)1 signaling cascade and enhanced the expression of the target gene Bim, leading to apoptosis in lung cancer cells. Overexpression of wild-type or a constitutively active mutant of FOXO3a enhanced shikonin-induced Bim expression. The NAD+-dependent histone deacetylase sirtuin (SIRT)1 amplified the pro-apoptotic effect by deacetylating FOXO3a, which induced EGR1 binding to the Bim promoter and activated Bim expression. Meanwhile, PI3K/AKT activity was enhanced, whereas that of FOXO3a was reduced and p300 was upregulated by treatment with a sublethal dose of shikonin. FOXO3a acetylation was enhanced by p300 overexpression, while shikonin-induced Bim expression was suppressed by p300 overexpression, which promoted cell survival. FOXO3a acetylation was increased by p300 overexpression and treatment with SIRT1 inhibitor, improving cell survival. In addition, shikonin-induced FOXO3a nuclear localization was blocked by AKT activation and SIRT1 inhibition, which blocked Bim expression and conferred resistance to the cytotoxic effects of shikonin. The EGR1 increase induced by shikonin was restored by pretreatment with SIRT1 inhibitor. These results suggest that shikonin induces apoptosis in some lung cancer cells via activation of FOXO3a/EGR1/SIRT1 signaling, and that AKT and p300 negatively regulate this process via Bim upregulation.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteína p300 Associada a E1A/metabolismo , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Proteína Forkhead Box O3/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Naftoquinonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/antagonistas & inibidores , Células A549 , Acetilação , Animais , Proteína 11 Semelhante a Bcl-2/genética , Proteína 11 Semelhante a Bcl-2/metabolismo , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Relação Dose-Resposta a Droga , Proteína p300 Associada a E1A/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Proteína Forkhead Box O3/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fatores de Tempo , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Food Sci Biotechnol ; 33(6): 1393-1405, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38585569

RESUMO

Various edible polymers [sodium alginate, carboxyl methylcellulose, sodium oleate, liquid paraffin, pectin, pullulan, polyvinyl acetate, and shellac (SHE)] as potato-coating materials and their effect on extending the shelf life of potatoes when combined with an edible coating and UV-C irradiation treatments were evaluated. As a result of the characterization of the edible polymers, SHE was selected as the optimal coating material because it had the best moisture and light barrier properties. SHE coating successfully prevented the greening, respiration, and sprouting of potatoes caused by exposure to light and oxygen. Additionally, it reduced weight loss by inhibiting transpiration on the potato surface. While the SHE coating did not exhibit antimicrobial effects, a significant effect was observed when combined with UV-C irradiation. This study suggests the potential of combined treatment of SHE coating and UV-C irradiation in extending the postharvest quality of potatoes.

13.
Int J Stem Cells ; 17(2): 204-211, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38246658

RESUMO

With recent advances in adeno-associated virus (AAV)-based gene therapy, efficacy and toxicity screening have become essential for developing gene therapeutic drugs for retinal diseases. Retinal organoids from human pluripotent stem cells (hPSCs) offer a more accessible and reproducible human test platform for evaluating AAV-based gene therapy. In this study, hPSCs were differentiated into retinal organoids composed of various types of retinal cells. The transduction efficiencies of AAV2 and AAV8, which are widely used in clinical trials of inherited retinal diseases, were analyzed using retinal organoids. These results suggest that retinal organoids derived from hPSCs serve as suitable screening platforms owing to their diverse retinal cell types and similarity to the human retina. In summary, we propose an optimal stepwise protocol that includes the generation of retinal organoids and analysis of AAV transduction efficacy, providing a comprehensive approach for evaluating AAV-based gene therapy for retinal diseases.

14.
Apoptosis ; 18(7): 870-81, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23546866

RESUMO

Shikonin derivatives exert powerful cytotoxic effects, induce apoptosis and escape multidrug resistance in cancer. However, the diverse mechanisms underlying their anticancer activities are not completely understood. Here, we demonstrated that shikonin-induced apoptosis is caused by reactive oxygen species (ROS)-mediated activation of Akt/ASK1/p38 mitogen-activated protein kinase (MAPK) and downregulation of p21(Cip1). In the presence of shikonin, inactivation of Akt caused apoptosis signal-regulating kinase 1 (ASK1) dephosphorylation at Ser83, which is associated with ASK1 activation. Shikonin-induced apoptosis was enhanced by inhibition of Akt, whereas overexpression of constitutively active Akt prevented apoptosis through modulating ASK1 phosphorylation. Silencing ASK1 and MKK3/6 by siRNA reduced the activation of MAPK kinases (MKK) 3/6 and p38 MAPK, and apoptosis, respectively. Antioxidant N-acetyl cysteine attenuated ASK1 dephosphorylation and p38 MAPK activation, indicating that shikonin-induced ROS is involved in the activation of Akt/ASK1/p38 pathway. Expression of p21(Cip1) was significantly induced in early response, but gradually decreased by prolonged exposure to shikonin. Overexpression of p21(Cip1) have kept cells longer in G1 phase and attenuated shikonin-induced apoptosis. Depletion of p21(Cip1) facilitated shikonin-induced apoptosis, implying that p21(Cip1) delayed shikonin-induced apoptosis via G1 arrest. Immunohistochemistry and in vitro binding assays showed transiently altered localization of p21(Cip1) to the cytoplasm by shikonin, which was blocked by Akt inhibition. The cytoplasmic p21(Cip1) actually binds to and inhibits the activity of ASK1, regulating the cell cycle progression at G1. These findings suggest that shikonin-induced ROS activated ASK1 by decreasing Ser83 phosphorylation and by dissociation of the negative regulator p21(Cip1), leading to p38 MAPK activation, and finally, promoting apoptosis.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/genética , Medicamentos de Ervas Chinesas/farmacologia , Regulação Neoplásica da Expressão Gênica , MAP Quinase Quinase Quinase 5/genética , Naftoquinonas/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Humanos , MAP Quinase Quinase Quinase 5/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Yeast ; 30(6): 219-27, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23609041

RESUMO

In the post-genomic era, an immediate challenge is to assign biological functions to novel proteins encoded by the genome. This challenge requires the use of a simple organism as a genetic tool and a range of new high-throughput techniques. Schizosacchromyces pombe is a powerful model organism used to investigate disease-related genes and provides useful tools for the functional analysis of heterologous genes. To expand the current array of experimental tools, we constructed two series of Sz. pombe expression vectors, i.e. general and Gateway vectors, containing nourseothricin-resistance markers. Vectors carrying nourseothricin-resistance markers possess advantages in that they do not limit the parental strains with auxotrophic mutations with respect to availability for use in clone selection and can be used together with vectors carrying nutrient markers in minimal media. We modified the pSLF173, pSLF273 and pSLF373 vectors carrying a triple haemagglutinin epitope (3×HA) and an Ura4 marker. The vectors described here contain the nmt1 promoter with three different episomal expression strengths for proteins fused with 3×HA, EGFP or DsRed at the N-terminus. These vectors represent an important contribution to the genome-wide investigation of multiple heterologous genes and for functional and genetic analysis of novel human genes.


Assuntos
Acetiltransferases/genética , Farmacorresistência Fúngica/genética , Vetores Genéticos/genética , Schizosaccharomyces/genética , Estreptotricinas/farmacologia , Meios de Cultura , Regulação Fúngica da Expressão Gênica , Plasmídeos/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão , Schizosaccharomyces/efeitos dos fármacos , Schizosaccharomyces/crescimento & desenvolvimento
16.
Artigo em Inglês | MEDLINE | ID: mdl-36833611

RESUMO

(1) Background: The purposes of this study were to develop a physical fitness evaluation program for new firefighters, to investigate whether there is a quality difference in performing CPR for cardiac arrest patients according to physical strength, and to provide basic data to improve CPR quality. (2) Methods: The subjects of this study were fire trainees who were appointed as firefighters for the first time in G province from 3 March 2021 to 25 June 2021. The age of the subjects was 25-29 years old, and their experience of working as a firefighter was less than three months. According to the purposes of the study, the researcher composed the Physical Fitness Evaluation Program, including the physical fitness evaluation method and steps, and requested a content expert group to modify and supplement the 'physical fitness assessment program'. The subjects were divided into four groups according to their levels of physical strength, and CPR was performed for 50 min in groups of two. A high-end Resuscitation Anne Simulator (Laeadal, Norway) mannequin was used to evaluate the quality of CPR. (3) Results: When comparing the difference in CPR quality, there were statistically significant differences in the number of chest compressions and compression depth, but all groups met the CPR guidelines. In the case of this study, it is thought that high-quality CPR could be performed because the subjects' average age was low and they continued to exercise to improve their physical strength for their role. (4) Conclusions: It was concluded that the fitness level of new firefighters confirmed by this study was sufficient for general high-quality CPR. In addition, for high-quality CPR, continuous management is required by developing a continuous CPR education and physical training program for all firefighters.


Assuntos
Reanimação Cardiopulmonar , Bombeiros , Parada Cardíaca , Humanos , Adulto , Reanimação Cardiopulmonar/métodos , Aptidão Física , Pressão
17.
Biochem Biophys Res Commun ; 417(1): 613-8, 2012 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-22182414

RESUMO

The small heat-shock protein Hsp9 from Schizosaccharomyces pombe was previously reported to be a homologue of Saccharomyces cerevisiae HSP12. Although Hsp9 is expressed in response to heat shock and nutritional limitation, its function is still not completely understood. Here, we explored the biological function of Hsp9 in S. pombe. The hsp9 gene might play a role in stress adaptation; hsp9 deletion caused heat sensitivity and overexpression induced heat tolerance. In addition, Hsp9 also contribute to cell cycle regulation in the nucleus. Δhsp9 cells grew more quickly and were shorter in length than wild-type cells. Moreover, Δhsp9 cells did not achieve checkpoint arrest under stress conditions, leading to cell death, and exhibited a short doubling time and short G2 phase. Overexpression of hsp9 induced cell cycle delay, increased the population of G2 phase cells, and rescued the phenotypes of cdc2-33, cdc25-22, Δrad24, and Δrad25 mutants, suggesting that Hsp9 probably regulates Cdc2 phosphorylation by modulating the Cdc25 activity. Indeed, immunoprecipitation experiments revealed that Hsp9 is associated with 14-3-3 and Cdc25. In Δhsp9 cells, the association of 14-3-3 with Cdc25 was weakened and Cdc2 phosphorylaton was reduced. Together, our data suggest that Hsp9 has dual functions in stress adaptation and regulating a G2-M checkpoint by the Cdc25 inactivation; this differs from S. cerevisiae HSP12, which maintains cell membrane stability under stress conditions.


Assuntos
Adaptação Fisiológica , Pontos de Checagem da Fase G2 do Ciclo Celular , Proteínas de Choque Térmico/fisiologia , Resposta ao Choque Térmico , Pontos de Checagem da Fase M do Ciclo Celular , Fosfoproteínas Fosfatases/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas de Schizosaccharomyces pombe/fisiologia , Proteínas 14-3-3/metabolismo , Proteínas de Choque Térmico/genética , Fosfoproteínas Fosfatases/genética , Fosforilação , Proteínas de Schizosaccharomyces pombe/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-23258984

RESUMO

The growth and development of adipose tissue are believed to require adipogenesis, angiogenesis, and extracellular matrix remodeling. As our previous study revealed that ginseng reduces adipose tissue mass in part by decreasing matrix metalloproteinase (MMP) activity in obese mice, we hypothesized that adipogenesis can be inhibited by ginseng and its active components ginsenosides (GSs). Treatment of 3T3-L1 adipocytes with Korean red ginseng extract (GE) inhibited lipid accumulation and the expression of adipocyte-specific genes (PPARγ, C/EBPα, aP2, and leptin). GE decreased both the mRNA levels and activity of MMP-2 and MMP-9 in 3T3-L1 cells. These effects were further inhibited by total GSs (TGSs) and individual GSs. TGSs and individual GSs also significantly decreased MMP-2 and MMP-9 reporter gene activities in the presence of phorbol 12-myristate 13-acetate (PMA), the MMP inducer. Among the GSs, Rb1 most effectively inhibited MMP activity. In addition, PMA treatment attenuated the inhibitory actions of GE and GSs on adipogenesis. Moreover, GE and GSs reduced the expression of NF-κB and AP-1, the transcription factors of MMP-2 and MMP-9. These results demonstrate that ginseng, in particular GSs, effectively inhibits adipogenesis and that this process may be mediated in part through the suppression of MMP-2 and MMP-9. Thus, ginseng and GSs likely have therapeutic potential for controlling adipogenesis.

19.
Stem Cell Res ; 65: 102950, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36283271

RESUMO

Given the advantage of being able to be extracted by a minimally invasive method, blood is regarded as a suitable cell source for reprogramming to establish induced pluripotent stem cells (iPSCs). Therefore, iPSCs established from patient derived peripheral blood mononuclear cells (PBMCs) is widely used to develop disease modeling to elucidate disease development. Here, PBMCs from a healthy man were reprogrammed into iPSCs using the Sendai virus. The established iPSC line, KRIBBi006-A, exhibit pluripotency marker and can differentiate into the three germ layers in vitro with normal karyotype. This iPSC line is a valuable resource as a control line for stem cell research of disease models and drug screening.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Masculino , Leucócitos Mononucleares , Pesquisa com Células-Tronco
20.
Biochem Biophys Res Commun ; 409(2): 211-6, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21565167

RESUMO

The Ras-related small GTP-binding protein RhoB is rapidly induced in response to genotoxic stresses caused by ionizing radiation. It is known that UV-induced RhoB expression results from the binding of activating transcription factor 2 (ATF2) via NF-Y to the inverted CCAAT box (-23) of the RhoB promoter. Here, we show that the association of c-Jun with the distal CCAAT box (-72) is primarily involved in UV-induced RhoB expression and p38 MAPK regulated RhoB induction through the distal CCAAT box. UV-induced RhoB expression and apoptosis were markedly attenuated by pretreatment with the p38 MAPK inhibitor. siRNA knockdown of RhoB, ATF2 and c-Jun resulted in decreased RhoB expression and eventually restored the growth of UV-irradiated Jurkat cells. In the reporter assay using luciferase under the RhoB promoter, inhibition of RhoB promoter activity by the p38 inhibitor and knockdown of c-Jun using siRNA occurred through the distal CCAAT box. Immunoprecipitation and DNA affinity protein binding assays revealed the association of c-Jun and p300 via NF-YA and the dissociation of histone deacetylase 1 (HDAC1) via c-Jun recruitment to the CCAAT boxes of the RhoB promoter. These results suggest that the activation of p38 MAPK primarily contributes to UV-induced RhoB expression by recruiting the c-Jun and p300 proteins to the distal CCAAT box of the RhoB promoter in Jurkat cells.


Assuntos
Apoptose/genética , Proteína p300 Associada a E1A/metabolismo , Regulação da Expressão Gênica , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transcrição Gênica/efeitos da radiação , Raios Ultravioleta , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteína rhoB de Ligação ao GTP/genética , Fator 2 Ativador da Transcrição/genética , Fator 2 Ativador da Transcrição/metabolismo , Fator de Ligação a CCAAT/metabolismo , Ativação Enzimática , Humanos , Células Jurkat , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
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