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1.
Front Cardiovasc Med ; 8: 806215, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35127867

RESUMO

Engineered heart tissues (EHTs) that are fabricated using human induced pluripotent stem cells (hiPSCs) have been considered as potential cardiac tissue substitutes in case of heart failure. In the present study, we have created hiPSC-derived cardiac organoids (hiPSC-COs) comprised of hiPSC-derived cardiomyocytes, human umbilical vein endothelial cells, and human fibroblasts. To produce a beating conduit for patients suffering from congenital heart diseases, we constructed scaffold-free tubular EHTs (T-EHTs) using hiPSC-COs and bio-3D printing with needle arrays. The bio-3D printed T-EHTs were cut open and transplanted around the abdominal aorta as well as the inferior vena cava (IVC) of NOG mice. The transplanted T-EHTs were covered with the omentum, and the abdomen was closed after completion of the procedure. Additionally, to compare the functionality of hiPSC-COs with that of T-EHTs, we transplanted the former around the aorta and IVC as well as injecting them into the subcutaneous tissue on the back of the mice. After 1 m of the transplantation procedures, we observed the beating of the T-EHTs in the mice. In histological analysis, the T-EHTs showed clear striation of the myocardium and vascularization compared to hiPSC-COs transplanted around the aorta or in subcutaneous tissue. Based on these results, bio-3D-printed T-EHTs exhibited a better maturation in vivo as compared to the hiPSC-COs. Therefore, these beating T-EHTs may form conduits for congenital heart disease patients, and T-EHT transplantation can form a treatment option in such cases.

2.
Foods ; 9(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244617

RESUMO

Consumption of fish is rapidly increasing worldwide. It is important to evaluate fish fillet quality because fish undergoes physical and chemical changes during frozen storage. Fish fillets exhibit formaldehyde (FA) accumulation from the decomposition of trimethylamine N-oxide. FA is a powerful protein denaturant; thus, it is important to avoid FA buildup during fish processing to preserve fish quality, especially texture. To determine where FA accumulates, in order to maintain the quality of fish fillets, we performed matrix-assisted laser desorption/ionization mass spectrometry imaging, aiming to identify muscle-derived peptides, which reflect conditions such as denaturation and/or aggregation. We used frozen sections from which lipophilic molecules were washed out and detected various peptide peaks. Furthermore, we tried to identify indices to represent fish fillet softening by protease treatment. We could detect characteristic peaks owing to FA and protease treatment; the findings were consistent with the results of texture profiles showing fish fillet's real solidity. These molecules might thus serve as effective markers to evaluate fish fillet quality.

3.
Biocontrol Sci ; 13(4): 111-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19127649

RESUMO

The colonial growth of Bacillus subtilis vegetative and spore cells was evaluated by determining the time course of the growth heat changes (growth thermogram) with a microbial calorimeter. The actual heat evolution curve (f (t) curve) obtained from the thermogram was in good agreement with the viable cell number changes. From the logarithmic f (t) curve, the exponential growth phase was estimated to be the period of between 31 and 35 h after inoculation and the growth rate constant (mu') was 0.36 h(-1). The f (t) curve was also obtained from the thermogram of the spore cells. The starting time of growth of the spore cells was 9 h later than that of the vegetative cells. This period corresponded to the germination period. The growth profile after germination was almost similar to that of the vegetative cells. The suppressive activities of sucrose monopalmitate (SMP) against the vegetative and spore cells were evaluated by the f (t) curves. Our results show that SMP inhibited metabolic inductions during the lag phase of the vegetative cells and the germination of the spore cells. Microbial calorimetry is a method suitable for non-destructive growth measurements of microbial colonies on the surface of a solid medium.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Sacarose/análogos & derivados , Edulcorantes/farmacologia , Calorimetria/métodos , Temperatura Alta , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/crescimento & desenvolvimento , Sacarose/metabolismo , Sacarose/farmacologia
4.
Sci Rep ; 7(1): 14085, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074999

RESUMO

Cell-based therapy has been proposed as an alternative to orthotopic liver transplantation. The novel transplantation of an in vitro-generated liver bud might have therapeutic potential. In vivo and ex vivo methods for growing a liver bud are essential for paving the way for the clinical translation of liver bud transplantation. We herein report a novel transplantation method for liver buds that are grown in vivo involving orthotopic transplantation on the transected parenchyma of the liver, which showed long engraftment and marked growth in comparison to heterotopic transplantation. Furthermore, this study demonstrates a method for rapidly fabricating scalable liver-like tissue by fusing hundreds of liver bud-like spheroids using a 3D bioprinter. Its system to fix the shape of the 3D tissue with the needle-array system enabled the fabrication of elaborate geometry and the immediate execution of culture circulation after 3D printing-thereby avoiding an ischemic environment ex vivo. The ex vivo-fabricated human liver-like tissue exhibited self-tissue organization ex vivo and engraftment on the liver of nude rats. These achievements conclusively show both in vivo and ex vivo methods for growing in vitro-generated liver buds. These methods provide a new approach for in vitro-generated liver organoids transplantation.


Assuntos
Fígado/crescimento & desenvolvimento , Engenharia Tecidual/métodos , Animais , Bioimpressão , Técnicas de Cultura de Células , Células Endoteliais da Veia Umbilical Humana , Humanos , Fígado/citologia , Transplante de Fígado , Tecido Parenquimatoso/citologia , Tecido Parenquimatoso/cirurgia , Impressão Tridimensional , Ratos , Técnicas de Cultura de Tecidos , Alicerces Teciduais , Transplante Heterólogo
5.
J Biochem ; 137(1): 41-50, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15713882

RESUMO

We found that CEL-I was a potent cytotoxic lectin. MDCK, HeLa, and XC cells were highly sensitive to CEL-I cytotoxicity and killed in a dose-dependent manner, whereas CHO, L929, and RAW264.7 cells were relatively resistant to CEL-I, and no significant toxicity was observed up to 10 microg/ml. Among these cell lines, MDCK cells showed the highest susceptibility to CEL-I cytotoxicity. A binding study using FITC-labeled CEL-I (F-CEL-I) revealed that the amounts of bound F-CEL-I on the sensitive cell lines were evidently greater than those on the resistant cell lines, suggesting that the different susceptibility of the cell lines to CEL-I cytotoxicity is partly explained by different efficiencies of binding of CEL-I to these cell lines. Interestingly, the cytotoxicity of CEL-I toward MDCK cells was more potent than those of other lectins such as WGA, PHA-L, and Con A, even though these lectins were capable of binding to MDCK cells at comparable levels to CEL-I. Since the cytotoxicity of CEL-I was strongly inhibited by GalNAc, the binding to cell surface specific carbohydrates is essential for the CEL-I cytotoxicity. The trypan blue dye exclusion test indicated that CEL-I caused a disorder of plasma membrane integrity as a relatively early event. CEL-I failed to induce the release of carboxyfluorescein (CF) from CF-loaded MDCK cells as seen for pore-forming hemolytic isolectin CEL-III, suggesting that the primary cellular target of CEL-I may be the plasma membrane, but its action mechanism differs from that of CEL-III. Although CEL-I induced dramatic cellular morphological changes in MDCK cells, neither typical apoptotic nuclear morphological changes nor DNA fragmentation was observed in CEL-I-treated MDCK cells even after such cellular changes. Our results demonstrated that CEL-I showed a potent cytotoxic effect, especially on MDCK cells, by causing plasma membrane disorder without induction of apoptosis.


Assuntos
Cucumaria/química , Lectinas Tipo C/metabolismo , Animais , Linhagem Celular , Cricetinae , Relação Dose-Resposta a Droga , Humanos , Lectinas Tipo C/isolamento & purificação , Camundongos , Ratos
6.
J Orthop Surg Res ; 10: 35, 2015 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-25890366

RESUMO

BACKGROUND: Osteoarthritis (OA) is a major joint disease in humans and many other animals. Consequently, medical countermeasures for OA have been investigated diligently. This study was designed to examine the regeneration of articular cartilage and subchondral bone using three-dimensional (3D) constructs of adipose tissue-derived mesenchymal stem cells (AT-MSCs). METHODS: AT-MSCs were isolated and expanded until required for genetical and immunological analysis and construct creation. A construct consisting of about 760 spheroids that each contained 5.0 × 10(4) autologous AT-MSCs was implanted into an osteochondral defect (diameter: 4 mm; depth: 6 mm) created in the femoral trochlear groove of two adult microminipigs. After implantation, the defects were monitored by computed tomography every month for 6 months in animal no. 1 and 12 months in animal no. 2. RESULTS: AT-MSCs were confirmed to express the premature genes and to be positive for CD90 and CD105 and negative for CD34 and CD45. Under specific nutrient conditions, the AT-MSCs differentiated into osteogenic, chondrogenic, and adipogenic lineages, as evidenced by the expressions of related marker genes and the production of appropriate matrix molecules. A radiopaque area emerged from the boundary between the bone and the implant and increased more steadily upward and inward for the implants in both animal no. 1 and animal no. 2. The histopathology of the implants after 6 months revealed active endochondral ossification underneath the plump fibrocartilage in animal no. 1. The histopathology after 12 months in animal no. 2 showed not only that the diminishing fibrocartilage was as thick as the surrounding normal cartilage but also that massive subchondral bone was present. CONCLUSIONS: The present results suggest that implantation of a scaffold-free 3D construct of AT-MSCs into an osteochondral defect may induce regeneration of the original structure of the cartilage and subchondral bone over the course of 1 year, although more experimental cases are needed.


Assuntos
Regeneração Óssea , Cartilagem Articular/fisiologia , Transplante de Células-Tronco Mesenquimais , Osteoartrite/terapia , Tecido Adiposo/citologia , Animais , Cartilagem Articular/diagnóstico por imagem , Feminino , Masculino , Projetos Piloto , Radiografia , Suínos , Porco Miniatura
7.
J Biochem ; 134(6): 927-33, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14769883

RESUMO

Ricin induced apoptotic nuclear morphological changes in mouse macrophage cell line RAW264.7 cells at concentrations sufficient to cause severe protein synthesis inhibition. Ricin also induced the release of tumor necrosis factor-alpha (TNF-alpha) from this cell line in a dose-dependent manner but the profile was bell-shaped. However, the isolated galactose-specific ricin B-chain had no such effects. These results suggest that the receptor-binding of ricin through the B-chain is not enough, and subsequent attack on the intracellular target, i.e., the 28S ribosomal RNA (rRNA), by the A-chain of internalized ricin is required for the effects of ricin. Z-D-CH2-DCB, a caspase family inhibitor, showed potent inhibition of the release of TNF-alpha from RAW264.7 cells as well as blockage of the induction of apoptosis by ricin. Furthermore, SB202190, a specific P38 mitogen-activated protein (MAP) kinase inhibitor that strongly inhibits the release of TNF-alpha, also showed significant inhibition of ricin-induced apoptosis. These results suggest that there may be cross-talk between the pathways leading to the release of TNF-alpha and apoptosis. Time course analysis revealed that the activation of p38 MAP kinase started prior to the induction of TNF-alpha release and apoptosis. Since the activation of p38 MAP kinase in ricin-treated RAW264.7 cells was not prevented by Z-D-CH2-DCB, the activation of p38 MAP kinase may occur upstream of the caspase cascade. Among the other protein synthesis inhibitors examined, modeccin and anisomycin, which can trigger a ribotoxic stress response similar to ricin, induced the release of TNF-alpha, but emetine and cycloheximide did not. These results suggest that the specific attack on the 28S ribosomal RNA and the resulting ribotoxic stress response may trigger the multiple signal transduction pathways through the activation of p38 MAP kinase, which in turn leads to TNF-alpha release and apoptosis.


Assuntos
Apoptose/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Ricina/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Fragmentação do DNA , Imidazóis/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Piridinas/farmacologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno
8.
J Biochem ; 132(3): 441-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12204114

RESUMO

We have found that a brefeldin A (BFA)-resistant mutant cell line derived from Vero cells (BER-40) is highly resistant to ricin-induced apoptosis as compared with parental Vero cells. In BER-40 cells, all apoptotic events caused by ricin including cytolysis, nuclear morphological changes, and DNA fragmentation occur to a lesser extent than in Vero cells, even though both cell lines show similar sensitivities to ricin-mediated inhibition of protein synthesis. Furthermore, no significant apoptotic signaling events, such as increases in caspase-3 and -9-like activities, release of cytochrome c from mitochondria, or the cleavage of PARP, were observed in BER-40 cells under the conditions at which these changes were evident in Vero cells. Intracellular biochemical changes associated with ricin-induced apoptosis, such as the depletion of glutathione and an increase in free Zn2+, were also less apparent in BER-40 cells than in Vero cells. BER-40 cells were also found to be highly resistant to apoptosis induced by other toxins with different intoxication mechanisms such as diphtheria toxin, modeccin, and anisomycin. These results suggest that the entire apoptotic signal transduction mechanism in BER-40 cells, which may be triggered after the inhibition of protein synthesis by toxins, becomes resistant. Since MDCK cells, a naturally BFA resistant cell line, are highly sensitive to ricin-induced apoptosis, it seems likely that the BFA resistance phenotype may not necessarily lead to resistance to apoptotic cell death. Probably the underlaying BFA-resistance mechanism in BER-40 cells is distinct from that in MDCK cells, and the resistance to ricin-induced apoptosis of BER-40 cells may be a unique phenotype acquired concomitantly with BFA-resistance.


Assuntos
Apoptose/efeitos dos fármacos , Brefeldina A/farmacologia , Resistência a Medicamentos/genética , Mutação , Inibidores da Síntese de Proteínas/farmacologia , Ricina/toxicidade , Animais , Antineoplásicos/farmacologia , Western Blotting , Caspase 3 , Caspases/metabolismo , Chlorocebus aethiops , Grupo dos Citocromos c/metabolismo , Cães , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Poli(ADP-Ribose) Polimerases/metabolismo , Células Vero
9.
Toxicol Lett ; 132(2): 141-51, 2002 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-12044548

RESUMO

We found that treatment of U937 cells with ZnCl(2) resulted in marked inhibition of ricin-induced DNA fragmentation and nuclear morphological change. Zn(2+) also completely inhibited the activation of caspase-3-, caspase-6-, and caspase-9-like proteases in ricin-treated cells, while no significant effect of Zn(2+) on these protease activities was observed when added directly to the lysate of ricin-treated cells, suggesting that Zn(2+) blocks the process of the activation of these caspases rather than the direct inhibition of the already activated enzymes. Fluorescence microscopic observation with Zn(2+) specific fluorescent probe dansylaminoethyl-cyclen suggested that there was a substantial increase in probe-detectable Zn(2+) in ricin-treated cells. Since the differences in the total Zn(2+) contents between ricin-treated and -untreated cells as measured with an atomic absorption spectrophotometer were too small to explain the increase in probe fluorescence in ricin-treated cells, it was suggested that release of Zn(2+) from intracellular stores or metalloproteins may occur rather than enhanced uptake from the medium. The Zn(2+) probe fluorescence change was observed prior to the depletion of intracellular glutathione. Carbobenzoxy-Asp-1-yl-[(2,6-dichlorobenzoyl)oxy]methane (Z-Asp-CH(2)-DCB), a caspase family protease inhibitor, prevented ricin-induced increase in Zn(2+) probe fluorescence. These results suggest that redistribution of intracellular Zn(2+) occurs during ricin-induced apoptosis as early apoptotic event, and exogenously added Zn(2+) may prevent such intracellular Zn(2+) redistribution resulting in the inhibition of apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Adstringentes/uso terapêutico , Ricina/antagonistas & inibidores , Sulfato de Zinco/uso terapêutico , Caspases/efeitos dos fármacos , Caspases/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Humanos , Ricina/toxicidade , Células U937
10.
Anim Sci J ; 84(2): 165-77, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23384359

RESUMO

We developed a system for measuring emissions from stored slurry by using a floating dynamic chamber. CH(4) , CO(2) , N(2) O and NH(3) emitted from the storage tank of a dairy cattle farm in eastern Hokkaido were measured during summer 2008 (7/16-8/6), fall 2008 (10/2-10/26), spring 2009 (6/2-6/21) and winter 2009 (3/11). Average daily gas emission rates in summer, fall and spring were, respectively, 54.8, 54.2 and 34.3 g/m(2) for CH(4) ; 602, 274 and 254 g/m(2) for CO(2) ; 55.4, 68.2 and trace mg/m(2) for N(2) O; and 0.55, 0.73 and 0.46 g/m(2) for NH(3) . CH(4) , CO(2) and NH(3) emission rates during the brief measurement period in winter were reduced to 1/4, 1/23 and 1/2, respectively, of summer emission rate levels. All gas emissions showed diurnal fluctuation and were greatest during the daytime, when the ambient temperature rose. CH(4) , NH(3) and CO(2) emissions increased significantly during the daytime, and the daily emission (in grams) of each gas was positively correlated with maximum daily temperature. According to the combined spring, summer and fall measurements, the CH(4) , N(2) O and NH(3) annual emission factors were 1.42% (g CH(4) /g volatile solids), 0.02% (g N(2) O-N/g total N) and 0.43% (g NH(3) -N/g total N), respectively.


Assuntos
Poluição do Ar/análise , Amônia/análise , Dióxido de Carbono/análise , Indústria de Laticínios , Monitoramento Ambiental/métodos , Esterco/análise , Metano/análise , Óxido Nitroso/análise , Animais , Bovinos , Mudança Climática , Gases , Estações do Ano , Temperatura
11.
Biol Pharm Bull ; 28(12): 2289-95, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16327167

RESUMO

Recently we discovered a bacterial strain (MS-02-063) that produces large amounts of red pigment (PG-L-1). Among the cell lines tested, U937 cells showed the highest susceptibility to PG-L-1 toxicity. PG-L-1 induced typical apoptotic nuclear morphological changes, and single cell gel electrophoresis revealed that PG-L-1 caused DNA fragmentation in U937 cells. In PG-L-1 treated U937 cells, the acidic compartment such as lysosomes disappeared, suggesting that PG-L-1-induced disorder of intracellular pH compartmentalization might trigger apoptotic signal. Since p38 MAP kinase inhibitor specifically prevented the PG-L-1 mediated cell death, p38 MAP kinase may be involved in the cytotoxic mechanism. In fact, immunoblot analysis of p38 MAP kinase revealed that phosphorylation of p38 MAP kinase occurred in PG-L-1-treated U937 cells. In addition to the activity to induce apoptotic cell death as reported in several PG family members, our chemiluminescence analysis suggested that PG-L-1 inhibited superoxide generation by 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated U937 cells in a dose-dependent manner. Since PG-L-1 had no effect on the chemiluminescence response caused by xanthine oxidase/hypoxanthine system, PG-L-1 acts on the enzyme system responsible for O(2)(-) generation rather than direct scavenging toward O(2)(-). Our results suggest that PG-L-1 causes multiple biochemical effects on the target cells such as increase in pH in acidic intracellular compartment, activation of p38 MAP kinase, inhibition of O(2)(-) generation, and eventually induces apoptotic cell death.


Assuntos
Antibacterianos/farmacologia , Apoptose , Gammaproteobacteria/metabolismo , Prodigiosina/análogos & derivados , Prodigiosina/toxicidade , Laranja de Acridina , Antibacterianos/toxicidade , Compartimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Immunoblotting , Medições Luminescentes , Prodigiosina/metabolismo , Serratia marcescens/metabolismo , Superóxidos/antagonistas & inibidores , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Células U937/efeitos dos fármacos , Células U937/metabolismo , Células U937/ultraestrutura , Proteínas Quinases p38 Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
J Cardiol ; 46(3): 97-103, 2005 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-16218427

RESUMO

OBJECTIVES: We assessed the clinical value of carotid intima-media thickness (IMT) for the differentiation of ischemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM). METHODS: We studied 38 patients who showed left ventricular dilation and low ejection fraction (< 40%) by cardiac catheterization. There were 15 patients with ICM which was defined as stenosis of > 75% at one major branch or more. Twenty-three patients were found to have DCM as diagnosed by histological examination using biopsy specimens. Carotid IMT visualized by B-mode imaging was measured at 16 sites in the extracranial carotid arteries, and the maximum IMT, mean IMT, and plaque score were calculated. These parameters together with cardiovascular risk factors including age, sex, hypertension, diabetes mellitus, hypercholesterolemia, cigarette smoking, and obesity were compared between the ICM and the DCM groups. RESULTS: The maximum IMT, mean IMT, and plaque score in the ICM group were 2.80 +/- 1.63 mm, 1.21 +/- 0.36 mm, 13.05 +/- 8.12, respectively, which were significantly higher than the corresponding parameters in the DCM group (1.19 +/- 0.51 mm, 0.73 +/- 0.15 mm, 1.52 +/- 2.51; p < 0.001, respectively). Furthermore, plaque score of greater than 5 was found to be an excellent diagnostic parameter for ICM with 91% sensitivity and 100% specificity. The cardiovascular risk factors did not differ between the two groups. CONCLUSIONS: Our observations demonstrate that assessment of carotid IMT is a clinically useful tool to differentiate ICM and DCM in patients with left ventricular dysfunction. In particular, coronary angiography should be recommended in patients with a plaque score of greater than 5.


Assuntos
Cardiomiopatia Dilatada/diagnóstico , Doenças das Artérias Carótidas/diagnóstico por imagem , Isquemia Miocárdica/diagnóstico , Ultrassonografia de Intervenção , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Túnica Íntima/patologia
13.
Cell Struct Funct ; 28(5): 475-85, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14745139

RESUMO

We found that the treatment with 1 mM butyric acid for 2 days renders Vero cells highly sensitive to ricin-induced apoptosis reflected by cytolysis concomitant with apoptotic cellular and nuclear morphological changes, DNA fragmentation, and increase in caspase-3 like activity, whereas butyric acid alone had no cytotoxic effect on Vero cells. During the treatment with butyric acid, gradual increase in alkaline phosphatase activity, an indicator for butyric acid-induced differentiation, was observed in Vero cells. Although the potency of ricin-mediated protein synthesis was increased in butyric acid-treated Vero cells as compared to untreated cells, the binding and internalization of ricin to the cells were not much affected. Furthermore, DNA fragmentation caused by other protein synthesis inhibitors such as diphtheria toxin and anisomysin were also highly potentiated in butyric acid-treated Vero cells, whereas the potencies of these toxins to inhibit the protein synthesis were not affected by butyric acid treatment. These results suggest that the apoptosis signaling pathway, which may be triggered by cytotoxic stress response caused by toxins, is sensitized in butyric acid-treated cells, while the pathways leading to the protein synthesis inhibition by these toxins are relatively unchanged. No significant differences in the expression levels of p21, p53, and Bcl-2 proteins were observed between butyric acid-treated and untreated Vero cells. The treatment with ricin resulted in the activation of p38 MAP kinase, and this activation occurred on an accelerated time schedule in butyric acid-treated Vero cells than in untreated cells. The specific inhibitor of p38 MAP kinase SB203580 showed a partial inhibitory effect on ricin-induced apoptosis in control Vero cells, but it was less effective in butyric acid-treated Vero cells. Taken together, our results suggest that butyric acid-treatment may result in sensitization of multiple intracellular signal transduction pathways including apoptotic signaling pathways and p38 MAP kinase pathway.


Assuntos
Apoptose/fisiologia , Ácido Butírico/metabolismo , Antagonistas dos Receptores Histamínicos/metabolismo , Ricina/metabolismo , Transdução de Sinais/fisiologia , Animais , Caspase 3 , Caspases/metabolismo , Tamanho Celular , Chlorocebus aethiops , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Fragmentação do DNA , Toxina Diftérica/metabolismo , Ativação Enzimática , Inibidores Enzimáticos/metabolismo , Imidazóis/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Inibidores da Síntese de Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Piridinas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Células Vero , Proteínas Quinases p38 Ativadas por Mitógeno
14.
Biosci Biotechnol Biochem ; 67(2): 258-63, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12728983

RESUMO

Enzymatically depolymerized guluronate and mannuronate oligomers were prepared from polyuronates with an alginate lyase from a Pseudoalteromonas sp., and their effects on mononuclear cells from human peripheral blood were examined. Conditioned medium prepared by the incubation of cells with an untreated polyuronate had little effect on growth of human leukemic U937 cells, but a medium prepared with depolymerized uronate oligomers inhibited their growth. Inhibition was greater in a medium prepared with guluronate oligomer than one prepared with mannuronate oligomer. The cytotoxic activity of the medium was heat-labile and nondialyzable. Apoptotic nuclear morphological changes and increased caspase-3-like activity were found in U937 cells treated with a medium prepared with depolymerized uronates. The medium prepared with purified tetra-guluronate and tetra-mannuronate also was cytotoxic; these effects were inhibited by antibodies to tumor necrosis factor-alpha. Our results suggested that enzymatically depolymerized guluronate and mannuronate oligomers induced the production of cytotoxic cytokines in human mononuclear cells, although the uronate polymers before depolymerization had no such activity.


Assuntos
Alginatos/metabolismo , Alginatos/farmacologia , Biopolímeros/metabolismo , Biopolímeros/farmacologia , Citocinas/biossíntese , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Alginatos/química , Alteromonas/enzimologia , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Biopolímeros/química , Caspase 3 , Caspases/metabolismo , Testes Imunológicos de Citotoxicidade , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Humanos , Leucócitos Mononucleares/citologia , Polissacarídeo-Liases/metabolismo , Células U937 , Ácidos Urônicos/química , Ácidos Urônicos/farmacologia
15.
Biosci Biotechnol Biochem ; 66(4): 835-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12036057

RESUMO

We compared the abilities of ricin, diphtheria toxin, cycloheximide, and anisomycin to induce apoptosis, using human myeloid leukemia U937 cells at the concentration of each toxin at which almost complete protein synthesis inhibition was attained within 3 h. Among these toxins, anisomycin was found to be the most potent apoptosis inducer. After a 6-h exposure to anisomycin (1 microg/ml), nearly 95% of the cells had apoptotic nuclear morphological changes, while 53%, 30%, and 10% of the cells showed apoptotic changes after exposure to ricin (0.1 microg/ml), diphtheria toxin (10 microg/ml), and cycloheximide (10 microg/ml), respectively. Furthermore, a rapid increase in caspase-3-like activity was observed in anisomycin-treated cells. A similar increase in caspase-3-like activity was also observed in ricin-treated cells on a slower time schedule. However, only a slight increase in the protease activity was induced by diphtheria toxin or cycloheximide even after 6 h of incubation. Since both ricin and anisomycin are known to act on 28S ribosomal RNA, our results suggest that this action mechanism may be responsible for their potent apoptosis induction, and protein synthesis inhibition alone is not sufficient to induce apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Anisomicina/farmacologia , Apoptose/fisiologia , Cicloeximida/farmacologia , Toxina Diftérica/farmacologia , Humanos , Cinética , Ricina/farmacologia , Células Tumorais Cultivadas , Células U937
16.
Mol Cell Biochem ; 252(1-2): 25-32, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14577573

RESUMO

Recently, several studies reported that urocortin (Ucn) had beneficial effects on cardiovascular system and was expressed both in the normal heart and in the heart of dilated cardiomyopathy (DCM), yet the relationship between high expression of Ucn and pathophysiology of Ucn in diseased heart has been discussed. Thus, the present study was designed to elucidate the expression of Ucn in the diseased heart by immunohistochemical approach using endomyocardial biopsy specimens. The involvement of immunoreactive Ucn in pathophysiology of cardiac disease was evaluated using endomyocardial biopsy specimens obtained from the patients with some heart diseases, including DCM and hypertrophic cardiomyopathy (HCM). Ucn was detected in all endomyocardial biopsy specimens of ventricular tissue obtained from the patients with such cardiac diseases, a specimens of atrial tissue, and normal heart specimens obtained from autopsy cases. In DCM patients, left ventricular end-diastolic pressure significantly elevated in severely stained group. On the contrary, in HCM patients, left ventricular ejection fraction was higher in the severely stained group. Ucn was expressed more abundantly in the diseased heart, especially in HCM and DCM, than in the normal heart. In conclusion, such close relationship between Ucn expression in the heart and cardiac function indicated that clinical features of Ucn resembled those of norepinephrine and Ucn could play a certain pathophysiological roles in the cardiac diseases.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Cardiopatias/metabolismo , Miocárdio/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Urocortinas
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