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1.
Biol Pharm Bull ; 41(8): 1203-1210, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068869

RESUMO

Both lipid accumulation and oxidative stress are major pathologic contributors to the development of hepatic steatosis. Treatment with molybdate reduces hepatic levels of lipids in diabetic rats. Potential activities of molybdate as an antioxidant have also been demonstrated in various animal models. In the present study, we evaluated the effects of sodium molybdate dihydrate (SM) on hepatic steatosis and associated disturbances in a widely used mouse model of the metabolic disease. Male C57Bl/6 mice at 10 weeks of age were fed a diet deficient in methionine and choline (MCD) and bottled water containing SM for four weeks. The SM treatment markedly attenuated MCD-induced accumulation of lipids, mainly triglycerides, in the liver. Lipid catabolic autophagic pathways were activated by SM in the MCD-fed mouse livers, as evidenced by a decreased level of p62 expression. MCD-induced oxidative damage, such as lipid and protein oxidation, was also alleviated by SM in the liver. However, the level of MCD-induced hepatocellular damage was not affected by SM. Taken together, these findings suggest that molybdate can be used in the treatment and prevention of hepatic steatosis without inducing adverse effects in the liver. To the best of our knowledge, this is the first experimental study to investigate the effects of molybdate in non-alcoholic fatty liver disease, and also the first that demonstrates molybdate-induced autophagy.


Assuntos
Fígado/efeitos dos fármacos , Molibdênio/farmacologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Deficiência de Colina , Dieta , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Metionina/deficiência , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
2.
Toxicol Appl Pharmacol ; 285(3): 159-69, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25902338

RESUMO

Cytochrome P450 (CYP) 1A1 is a heme-containing enzyme involved in detoxification of hydrophobic pollutants. Its Ala62Pro variant has been identified previously. Ala62 is located in α-helix A of CYP1A1. Residues such as Pro and Gly are α-helix breakers. In this study, the Ala62Pro variant was characterized using heterologous expression. E. coli expressing the Ala62Pro variant, and the purified variant protein, had lower CYP (i.e. holoenzyme) contents than their wild-type (WT) equivalents. The CYP variant from E. coli and mammalian cells exhibited lower 7-ethoxyresorufin O-dealkylation (EROD) and benzo[a]pyrene hydroxylation activities than the WT. Enhanced supplementation of a heme precursor during E. coli culture did not increase CYP content in E. coli expressing the variant, but did for the WT. As for Ala62Pro, E. coli expressing an Ala62Gly variant had a lower CYP content than the WT counterpart, but substitution of Ala62 with α-helix-compatible residues such as Ser and Val partially recovered the level of CYP produced. Microsomes from mammalian cells expressing Ala62Pro and Ala62Gly variants exhibited lower EROD activities than those expressing the WT or Ala62Val variant. A region harboring α-helix A has interactions with another region containing heme-interacting residues. Site-directed mutagenesis analyses suggest the importance of interactions between the two regions on holoenzyme expression. Together, these findings suggest that the Ala62Pro substitution leads to changes in protein characteristics and function of CYP1A1 via structural disturbance of the region where the residue is located.


Assuntos
Citocromo P-450 CYP1A1/genética , Proteínas Recombinantes/genética , Sequência de Aminoácidos , Animais , Benzo(a)pireno/metabolismo , Células CHO , Clonagem Molecular , Cricetulus , Citocromo P-450 CYP1A1/metabolismo , Escherichia coli/genética , Heme/química , Humanos , Hidroxilação , Microssomos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fases de Leitura Aberta , Oxazinas/metabolismo , Polimorfismo Genético , Conformação Proteica , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
3.
Ecotoxicology ; 24(5): 1064-72, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25762104

RESUMO

Eurasian otters (Lutra lutra) are endangered worldwide, but the specific cause of their decline has not been determined. This study analyzed the concentrations of potentially toxic trace elements, including As, Cd, Pb, Hg, Se, Cu, Mn, and Zn, in the liver, kidney, and lung tissues of Eurasian otters in South Korea. There were high individual variations in the tissue concentrations of all the elements analyzed. The kidneys had the highest concentrations of Cd and Se among the three tissue groups, and the livers had the highest concentrations of Cu, Mn, Zn, and Hg. The Pb and As concentrations in the livers were not significantly different from those in the kidneys, and the lungs had the lowest concentrations of all the elements analyzed. The age-related bioaccumulation of Cd and Hg was evident in the three tissue groups, and of Se in the kidneys. The Pb concentration was higher in the livers of juveniles compared with those of adults and the Zn concentration was higher in the lungs of juveniles. There were no apparent gender differences in the concentrations of the elements analyzed among the tissue groups. The Se concentration correlated with the Hg concentration in the livers and kidneys, and with the Cd concentration in the kidneys. The Hg and Cd levels correlated in the three tissue groups. The Cu and Zn levels also correlated in the livers and kidneys. In general, the element concentrations were within the ranges reported by previous studies of this species from European countries, except for Cd and Hg, the levels of which were mostly lower than those reported previously. These findings may provide baseline information to facilitate the conservation of the Eurasian otter. To the best of our knowledge, this is the first available study of trace element concentrations in the tissues of Eurasian otters from South Korea or Asian countries.


Assuntos
Lontras/fisiologia , Oligoelementos/análise , Poluentes Químicos da Água/análise , Fatores Etários , Animais , Espécies em Perigo de Extinção , Feminino , Rim/química , Fígado/química , Pulmão/química , Masculino , República da Coreia
4.
Proteomics ; 14(15): 1833-43, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24866292

RESUMO

Arsenic is an environmental pollutant, and its liver toxicity has long been recognized. The effect of arsenic on liver protein expression was analyzed using a proteomic approach in monkeys. Monkeys were orally administered sodium arsenite (SA) for 28 days. As shown by 2D-PAGE in combination with MS, the expression levels of 16 proteins were quantitatively changed in SA-treated monkey livers compared to control-treated monkey livers. Specifically, the levels of two proteins, mortalin and tubulin beta chain, were increased, and 14 were decreased, including plastin-3, cystathionine-beta-synthase, selenium-binding protein 1, annexin A6, alpha-enolase, phosphoenolpyruvate carboxykinase-M, erlin-2, and arginase-1. In view of their functional roles, differential expression of these proteins may contribute to arsenic-induced liver toxicity, including cell death and carcinogenesis. Among the 16 identified proteins, four were selected for validation by Western blot and immunohistochemistry. Additional Western blot analyses indicated arsenic-induced dysregulation of oxidative stress related, genotoxicity-related, and glucose metabolism related proteins in livers from SA-treated animals. Many changes in the abundance of toxicity-related proteins were also demonstrated in SA-treated human hepatoma cells. These data on the arsenic-induced regulation of proteins with critical roles may help elucidate the specific mechanisms underlying arsenic-induced liver toxicity.


Assuntos
Arsenitos/toxicidade , Fígado/efeitos dos fármacos , Proteínas/análise , Proteoma/efeitos dos fármacos , Compostos de Sódio/toxicidade , Animais , Eletroforese em Gel Bidimensional , Células Hep G2 , Histocitoquímica , Humanos , Fígado/química , Fígado/metabolismo , Macaca fascicularis , Masculino , Proteínas/metabolismo , Proteômica
5.
BMC Vet Res ; 10: 43, 2014 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-24533486

RESUMO

BACKGROUND: Infection by Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae, either alone or together, causes serious respiratory diseases in pigs. RESULTS: To develop an efficient multi-disease subunit vaccine against these pathogens, we produced a chimeric protein called Ap97, which comprises a deletion derivative of the N-terminal region of the A. pleuropneumoniae ApxIII toxin (ApxN) and the R1 and R2 repeats of M. hyopneumoniae P97 adhesin (P97C), using an E. coli expression system.The levels of both IgG1 and IgG2a isotypes specific for ApxN and P97C in the sera of Ap97-immunized mice increased, and Ap97 induced the secretion of IL-4 and IFN-γ by mouse splenocytes. Antisera from mice and pigs immunized with Ap97 readily reacted with both native ApxIII and P97 proteins. In addition, immunization with the Ap97 vaccine effectively protected pigs against challenge with both pathogens. CONCLUSIONS: These findings suggest that Ap97 confers immunogenicity, and is an effective vaccine that protects pigs against infection by M. hyopneumoniae and A. pleuropneumoniae.


Assuntos
Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/metabolismo , Mycoplasma hyopneumoniae/metabolismo , Pneumonia Suína Micoplasmática/prevenção & controle , Proteínas Recombinantes/imunologia , Infecções por Actinobacillus/prevenção & controle , Animais , Vacinas Bacterianas/imunologia , Sequência de Bases , Citocinas , Escherichia coli/metabolismo , Feminino , Regulação Bacteriana da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Anotação de Sequência Molecular , Organismos Livres de Patógenos Específicos , Suínos
6.
J Appl Toxicol ; 33(2): 78-89, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22936301

RESUMO

Silver nanoparticles (AgNPs) have emerged as an important class of nanomaterials for a wide range of industrial and medical applications. However, the unique properties of AgNPs could potentially lead to unexpected hazards to both human health and the well being of the environment. Possible mechanisms of AgNP-induced toxicity include the stimulation of oxidative stress, genotoxicity and apoptosis. In this study, a number of previous studies are therefore summarized that demonstrate oxidative stress-, genotoxicity- and apoptosis-related changes brought about by AgNPs in cultured cells and animal tissues. The physicochemical properties of AgNPs that are involved in encouraging such changes are also discussed.


Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Nanopartículas Metálicas/toxicidade , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Prata/toxicidade , Animais , Células Cultivadas , Humanos , Espécies Reativas de Oxigênio/metabolismo
7.
J Ethnopharmacol ; 317: 116801, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37330073

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Hedera helix L. (HH) leaves and Coptidis rhizoma (CR) have traditionally been used to treat respiratory conditions. AG NPP709, which is formulated using extracts of both these herbs, has been developed as an expectorant and antitussive. AIM OF THE STUDY: The objective was to evaluate the subchronic toxicity and toxicokinetic characteristics of AG NPP709 in laboratory rats. MATERIALS AND METHODS: AG NPP709 was orally administered to rats at doses of up to 2.0 g/kg/day for a duration of 13 weeks. Various health parameters were measured throughout the treatment period. At the end of the treatment, a necropsy was conducted and additional parameters were analyzed. Toxicokinetic analyses were also performed on hederacoside C and berberine, the active components of HH leaves and CR, respectively, in the plasma of rats treated with AG NPP709. RESULTS: AG NPP709-treated rats exhibited several health issues, such as reduced feed intake, altered differential white blood cell (WBC) count, increased plasma Alb/Glo ratio in females, and reduced kidney weight in males. However, these changes appeared to be incidental and fell within the typical range for healthy animals of this species. Additionally, toxicokinetic analysis of hederacoside C and berberine showed no accumulation in the plasma of rats during the repeated treatments with AG NPP709. CONCLUSIONS: Our study demonstrates that AG NPP709 does not have any harmful effects on rats under experimental conditions. Based upon these findings, the no observed adverse effect level of AG NPP709 can be estimated to be 2.0 g/kg/day in rats.


Assuntos
Berberina , Masculino , Feminino , Ratos , Animais , Ratos Sprague-Dawley , Toxicocinética , Extratos Vegetais
8.
Biol Pharm Bull ; 34(11): 1748-52, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22040890

RESUMO

Catalase protects cells from reactive oxygen species-induced damage by catalyzing the breakdown of hydrogen peroxide to oxygen and water. Arsenite decreases catalase activity; it activates phosphatidylinositol 3-kinase (PI3K) and its key downstream effector Akt in a variety of cells. The PI3K pathway is known to inhibit catalase expression. c-Met, an upstream regulator of PI3K and Akt, is also involved in the regulation of catalase expression. To examine the involvement of c-Met and PI3K pathways in the arsenite-induced downregulation of catalase, catalase mRNA and protein expression were analyzed in the human hepatoma cell line HepG2 treated with arsenite and either an inhibitor of c-Met (PHA665752 (PHA)) or of PI3K (LY294002 (LY)). Arsenite treatment markedly activated Akt and decreased the levels of both catalase mRNA and protein. Both PHA and LY attenuated arsenite-induced activation of Akt. PHA and LY treatment also prevented the inhibitory effect of arsenite on catalase protein expression but did not affect the level of catalase mRNA. These findings suggest that arsenite-induced inhibition of catalase expression is regulated at the mRNA and post-transcriptional levels in HepG2 cells, and that the post-transcriptional regulation is mediated via c-Met- and PI3K-dependent mechanisms.


Assuntos
Arsenitos/farmacologia , Catalase/metabolismo , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Catalase/genética , Cromonas/farmacologia , Regulação para Baixo , Ativação Enzimática/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Indóis/farmacologia , Redes e Vias Metabólicas/efeitos dos fármacos , Morfolinas/farmacologia , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sulfonas/farmacologia
9.
J Appl Toxicol ; 31(5): 455-62, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21404309

RESUMO

Genomic analysis in the local lymph node assays (LLNAs) is useful for assessing skin sensitization of chemicals and providing insights into mechanisms of sensitization. In this study, we collected 1406 genes from previous microarray findings, validated changes in their expression by RT-PCR analysis in local lymph nodes draining skin exposed to different sensitizers, and interpreted their biological function through pathway-based genomic analysis, in which 468 genes were identified as being in the KEGG pathway database. The top-ranked functions (P < 0.01) identified as being affected by the sensitizers were associated with aspects of cell growth, such as DNA replication, cell cycle regulation and pyrimidine metabolism. All the sensitizers tested (DNCB, OXA and TDI) induced significant up-regulation of Psme4, which is associated with DNA replication; Tfdp1, which is related to cell cycle regulation; and Dut, which is involved in pyrimidine metabolism. Specific changes were also shown in functional categories related to the immune response, including cytokines and their receptors. Genes identified in these functional categories, such as Ccl21c, Cxcl9, Cxcl10, Ifng and Il12rb1, were found to have functional relevance. These findings may enhance our understanding and assessment of chemical sensitizers, and enable us to distinguish sensitizers from irritants and to classify chemicals as contact sensitizers.


Assuntos
Alérgenos/toxicidade , Expressão Gênica/efeitos dos fármacos , Ensaio Local de Linfonodo , Linfonodos/efeitos dos fármacos , Administração Tópica , Animais , Óleo de Cróton/toxicidade , Dinitroclorobenzeno/toxicidade , Genômica , Linfonodos/metabolismo , Linfonodos/patologia , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Oxazolona/toxicidade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tolueno 2,4-Di-Isocianato/toxicidade
10.
Toxicol Lett ; 184(3): 151-8, 2009 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19061943

RESUMO

BACKGROUND: It has been suggested that the altered iron metabolism in liver tumors, characterized by the iron-deficient phenotype, is of importance for tumor growth. AIM: This study was performed to elucidate the mechanisms underlying iron deficiency in liver tumors by examining how the liver tumor development affects the expression of iron metabolism-related genes. METHODS: Iron metabolism reference values were analyzed in the sera of diethylnitrosamine-induced hepatocellular adenoma-bearing mice. Expression of iron metabolism-related genes was analyzed in adenomas and surrounding non-tumor tissues, and a subgroup of adenoma-bearing mice loaded with iron 72h before sacrifice. RESULTS: Iron content of the adenoma tissues was 2.0-2.5-fold lower compared to surrounding and age-matched control tissues. There was no significant difference in serum iron levels between the adenoma-bearing and control mice, while the adenoma-bearing mice exhibited a 2.4-fold lower level of serum transferrin saturation. Expression of iron metabolism-related genes was dysregulated in the adenomas. Iron loading affected protein expression similarly in the adenomas and surrounding tissues suggesting that iron-responsive regulation of the proteins was not impaired. However, the mRNA expression for ceruloplasmin and divalent metal transporter 1 (DMT1) IRE(+) in the adenomas was altered independently of iron status, and the dysregulation may contribute to diminished iron content. CONCLUSION: These findings suggest that diethylnitrosamine-induced liver adenoma-bearing mice have abnormal iron metabolism and that dysregulation of iron metabolism-related genes contributes to iron deficiency in the adenomas.


Assuntos
Adenoma de Células Hepáticas/genética , Regulação Neoplásica da Expressão Gênica , Ferro/metabolismo , Neoplasias Hepáticas Experimentais/genética , Adenoma de Células Hepáticas/induzido quimicamente , Adenoma de Células Hepáticas/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Cobre/metabolismo , Dietilnitrosamina , Ferritinas/genética , Ferritinas/metabolismo , Hepcidinas , Immunoblotting , Injeções Subcutâneas , Ferro/sangue , Complexo Ferro-Dextran/administração & dosagem , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transferrina/metabolismo
11.
J Vet Med Sci ; 71(10): 1317-23, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19887737

RESUMO

Apx toxins have been identified as important virulence factors of Actinobacillus pleuropneumoniae, the etiologic agent of porcine pleuropneumonia. In some A. pleuropneumoniae serotypes, Apx toxins are secreted by the cell membrane proteins encoded by apxIIIB and apxIIID genes. In an effort to develop a live vaccine strain against A. pleuropneumoniae, we inactivated the apxIIIB and apxIIID genes in A. pleuropneumoniae 1536, a serotype 2 strain, resulting in the DeltaapxIIIB/DapxIIID mutant strain (1536DeltaBDeltaD). Immunization of pigs with live 1536DeltaBDeltaD A. pleuropneumoniae conferred protection against homologous challenge with wild-type A. pleuropneumoniae 1536. Thus, impaired Apx toxin secretion may decrease the virulence of A. pleuropneumoniae and may be an effective strategy for the development of a live-attenuated A. pleuropneumoniae vaccine.


Assuntos
Actinobacillus pleuropneumoniae/classificação , Actinobacillus pleuropneumoniae/genética , Proteínas de Bactérias/genética , Actinobacillus pleuropneumoniae/patogenicidade , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Sorotipagem , Virulência
12.
Toxicology ; 250(2-3): 116-23, 2008 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-18652873

RESUMO

The murine local lymph node assay (LLNA) has been extensively utilized to evaluate sensitizing chemicals. However, there have been some concerns that its use to discriminate between classes of chemicals is minimal. It is thus desirable to identify better or alternative immune endpoints with in LLNA itself. Here, we evaluated the protein and/or mRNA levels of cytokines and granzyme B (GzmB), a cytotoxic lymphocyte product, to discriminate between sensitizers and irritants and to characterize the chemical sensitizers when used as supplemental indicators in LLNA endpoints. For this, CBA/N mice were topically treated daily with a well-known chemical sensitizer such as a strong contact sensitizer 1-chloro-2,4-dinitrobenzene (DNCB), a skin contact sensitizer 2-phenyl-4-ethoxymethylene-5-oxazolone (OXA), and a skin or respiratory sensitizer toluene 2,4-diisocyanate (TDI), and the non-sensitizing irritants, croton oil (CRO) and nonanoic acid (NA), for 3 consecutive days. The protein and/or mRNA levels in auricular lymph nodes draining the ear skin were then analyzed by real-time RT-PCR and immunoassay. The sensitizers, but not the irritants, evoked pronounced interleukin (IL)-2, IL-3 and IL-4 or interferon (IFN)-gamma. Significantly, different sensitizers evoked different cytokine patterns of IL-4 and IFN-gamma, as DNCB strongly up-regulated both IFN-gamma and IL-4, OXA up-regulated IFN-gamma strongly but IL-4 weakly, and TDI up-regulated IL-4 strongly but IFN-gamma weakly. The sensitizers also strongly up-regulated GzmB mRNA, while the irritants had a much weaker effect. Thus, these cytokines and GzmB mRNA may be useful as additional endpoints for discriminating between irritants and sensitizers or contact and respiratory sensitizers in the LLNA.


Assuntos
Citocinas/biossíntese , Dermatite Alérgica de Contato/diagnóstico , Dermatite de Contato/diagnóstico , Pavilhão Auricular/metabolismo , Granzimas/biossíntese , Irritantes/toxicidade , Ensaio Local de Linfonodo , Linfonodos/metabolismo , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Animais , Diagnóstico Diferencial , Dinitroclorobenzeno/toxicidade , Pavilhão Auricular/efeitos dos fármacos , Feminino , Imunoensaio , Linfonodos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos CBA , Ocitocina/análogos & derivados , Ocitocina/toxicidade , RNA/biossíntese , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tolueno 2,4-Di-Isocianato/toxicidade
13.
Toxicol Lett ; 180(3): 222-9, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18662754

RESUMO

As the applications of industrial nanoparticles are being developed, the concerns on the environmental health are increasing. Cytotoxicities of titanium dioxide nanoparticles of different concentrations (5, 10, 20 and 40 microg/ml) were evaluated in this study using a cultured human bronchial epithelial cell line, BEAS-2B. Exposure of the cultured cells to nanoparticles led to cell death, reactive oxygen species (ROS) increase, reduced glutathione (GSH) decrease, and the induction of oxidative stress-related genes such as heme oxygenase-1, thioredoxin reductase, glutathione-S-transferase, catalase, and a hypoxia inducible gene. The ROS increase by titanium dioxide nanoparticles triggered the activation of cytosolic caspase-3 and chromatin condensation, which means that titanium dioxide nanoparticles exert cytotoxicity by an apoptotic process. Furthermore, the expressions of inflammation-related genes such as interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-8 (IL-8), TNF-a, and C-X-C motif ligand 2 (CXCL2) were also elevated. The induction of IL-8 by titanium dioxide nanoparticles was inhibited by the pre-treatment with SB203580 and PD98059, which means that the IL-8 was induced through p38 mitogen-activated protein kinase (MAPK) pathway and/or extracellular signal (ERK) pathway. Uptake of the nanoparticles into the cultured cells was observed and titanium dioxide nanoparticles seemed to penetrate into the cytoplasm and locate in the peri-region of the nucleus as aggregated particles, which may induce direct interactions between the particles and cellular molecules, to cause adverse biological responses.


Assuntos
Apoptose/efeitos dos fármacos , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Titânio/toxicidade , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromossomos/efeitos dos fármacos , Cromossomos/ultraestrutura , Corantes Fluorescentes , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Humanos , Indóis , Espécies Reativas de Oxigênio/metabolismo
14.
Toxicol Lett ; 177(1): 1-9, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18242016

RESUMO

There has been some concern that certain non-sensitizing irritants may yield false positive results in the murine local lymph node assay (LLNA). This study compared gene expression profiles in lymph nodes draining skin following exposure to sensitizers and irritants, to identify gene transcripts that could distinguish sensitizers from irritants. After treating CBA/N mouse ears for 3 days with the sensitizers 1-chloro-2,4-dinitrobenzene, 2-phenyl-4-ethoxymethylene-5-oxazolone, or toluene-2,4-diisocyanate or the non-sensitizing irritants croton oil or nonanoic acid, auricular lymph nodes and ear tissues were excised. Sensitizer-induced changes in parameters such as ear thickness, lymph node weight, and cell count also occurred in irritant-treated mouse tissues. However, gene transcripts such as Ifi27, Il12rb1, Ifng, and Zbp1, which are related to T-cell activation, were shown by gene expression microarrays and real-time RT-PCR analyses to be up-regulated in auricular lymph nodes by sensitizers exclusively. These findings suggest that gene expression analysis may enable distinction between sensitizing chemicals and non-sensitizing irritants.


Assuntos
Alérgenos/toxicidade , Pavilhão Auricular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Irritantes/toxicidade , Linfonodos/efeitos dos fármacos , Pele/efeitos dos fármacos , Alérgenos/classificação , Animais , Pavilhão Auricular/metabolismo , Pavilhão Auricular/patologia , Feminino , Expressão Gênica/genética , Perfilação da Expressão Gênica , Irritantes/classificação , Ensaio Local de Linfonodo , Linfonodos/patologia , Camundongos , Camundongos Endogâmicos CBA , Análise de Sequência com Séries de Oligonucleotídeos , Tamanho do Órgão/efeitos dos fármacos , RNA Mensageiro/metabolismo , Pele/metabolismo , Pele/patologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
15.
J Vet Sci ; 19(1): 99-106, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28927254

RESUMO

Exercise capacity is a valuable trait in horses, and it has been used as a horse selection criterion. Although exercise affects molecular homeostasis and adaptation in horses, the mechanisms underlying these effects are not fully described. This study was carried out to identify changes in the blood profiles of microRNAs (miRNAs) and mRNAs induced by exercise in horse leukocytes. Total RNAs isolated from the peripheral blood leukocytes of four Warmblood horses before and after exercise were subjected to next-generation sequencing (NGS) and microarray analyses to determine the miRNA and mRNA expression profiles, respectively. The expressions of 6 miRNAs, including 4 known and 2 novel miRNAs, were altered by exercise. The predicted target genes of the differentially expressed miRNAs identified by NGS were matched to the exercise-induced mRNAs determined by microarray analysis. Five genes (LOC100050849, LOC100054517, KHDRBS3, LOC100053996, and LOC100062720) from the microarray analysis were matched to the predicted target genes of the 6 miRNAs. The subset of mRNAs and miRNAs affected by exercise in peripheral blood leukocytes may be useful in elucidating the molecular mechanisms of exercise-associated physiology in horses.


Assuntos
Cavalos/genética , Leucócitos/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Transcriptoma , Animais , Cavalos/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo
16.
Toxicol In Vitro ; 21(5): 870-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17416483

RESUMO

This study evaluated oxidative stress-induced apoptosis as a possible mechanism of arsenite toxicity in zebrafish liver cell line (ZFL cells). The heat shock protein 70 (HSP70), a chaperone protein, appears to provide protection against oxidative stress and apoptosis. Using the MTT assay, we demonstrated that survival of ZFL cells treated with arsenite for 24h decreased in a dose-dependent manner. The possible mechanisms that promote the cytotoxicity of arsenite were addressed. Cell viability assays revealed that arsenite caused a dose-dependent increase in cell death, and pretreatment of the ZFL cells with antioxidants blunted these effects. Antioxidants such as N-acetyl-cysteine (NAC, 5 mM) and dithiothreitol (DTT, 80 microM) significantly prevented ZFL cells from arsenite-induced death. Nuclear staining was performed using 1 microg/ml Hoechst, and cells were analyzed with a fluorescent microscope. Arsenite (30 microM) induced massive apoptosis that was identified by morphology and condensation and fragmentation of the nuclei of the ZFL cells. Pretreatment with NAC or DTT before arsenite insult effectively protected the cells against oxidative stress-induced apoptosis from the arsenite. Using a transfected human hsp 70 promoter-enhanced green fluorescent protein (EGFP) reporter, pHhsp70-EGFP, the induction of HSP70 against oxidative stress-induced apoptosis by arsenite was observed. The induction of HSP70 by arsenite increased in a dose-dependent manner, and pretreatment of transfected ZFL cells with NAC or DTT before arsenite insult reduced EGFP expression. Taken together, our results provide evidence that stimulation of the heat shock response is a sensitive biomarker of arsenic exposure and that arsenite causes oxidative stress-induced apoptosis in ZFL cells.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Arsenitos/antagonistas & inibidores , Arsenitos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/patologia , Acetilcisteína/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ditiotreitol/farmacologia , Relação Dose-Resposta a Droga , Genes Reporter/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/fisiologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Plasmídeos/genética , Transfecção , Azul Tripano , Peixe-Zebra
17.
Oncotarget ; 8(38): 63370-63381, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28968997

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is categorized into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) and has emerged as a risk factor for more critical clinical conditions. However, the underlying mechanisms of NAFLD pathogenesis are not fully understood. In this study, expression of proteins associated with endoplasmic reticulum (ER) stress, apoptosis and autophagy were analyzed in normal, NAFL and NASH human livers by western blotting. Levels of some ER stress-transducing transcription factors, including cleaved activating transcription factor 6, were higher in NASH than in the normal tissues. However, the expression of a majority of the ER chaperones and foldases analyzed, including glucose-regulated protein 78 and ER protein 44, was lower in NASH than in the normal tissues. Levels of apoptosis markers, such as cleaved poly (ADP-ribose) polymerase, were also lower in NASH tissues, in which expression of some B-cell lymphoma-2 family proteins was up- or down-regulated compared to the normal tissues. The level of the autophagy substrate p62 was not different in NASH and normal tissues, although some autophagy regulators were up- or down-regulated in the NASH tissues compared to the normal tissues. Levels of most of the proteins analyzed in NAFL tissues were either similar to those in one of the other two types, NASH and normal, or were somewhere in between. Together, these findings suggest that regulation of certain important tissues processes involved in protein quality control and cell survival were broadly compromised in the NAFLD tissues.

18.
J Vet Med Sci ; 79(8): 1327-1334, 2017 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-28652520

RESUMO

Cytochrome P450 1A1 (CYP1A1) is a heme-containing mono-oxygenase involved in metabolism of environmental contaminants. Two variants of dog CYP1A1 with a single residue difference were identified and designated Sap1 and Sap2. Compared with Sap1, Sap2 had a Trp50Leu substitution. The biochemical characteristics of the variants were comparatively analyzed using heterologous expression in Escherichia coli. The membrane fraction of E. coli expressing Sap2 exhibited higher CYP holoprotein and heme contents than the Sap1-containing membranes, although the level of total CYP1A1 protein (i.e., apoprotein + holoprotein) was comparable between the groups. As normalized to holo-CYP content, the Sap2-expressing membranes showed lower CYP1A1-specific enzyme activities, such as 7-ethoxyresorufin O-dealkylation (EROD), than the Sap1 group. In single substitution variants of residue 50, proteins with hydrophobic residues having mass similar to Leu exhibited lower EROD activities than those with hydrophobic residues having larger mass than Leu. In addition, variants with polar or charged residues having mass similar to Leu showed activities that were comparable to those of Sap2. Taken together, these findings suggest that the Trp50Leu substitution leads to an enhancement of holo-CYP1A1 formation, but diminishes the enzyme activity because of the small size of Leu compared with Trp.


Assuntos
Citocromo P-450 CYP1A1/genética , Proteínas Recombinantes/genética , Sequência de Aminoácidos , Animais , Benzo(a)pireno/metabolismo , Clonagem Molecular , Citocromo P-450 CYP1A1/metabolismo , Remoção de Radical Alquila , Cães , Escherichia coli/genética , Heme/química , Hidroxilação , Leucócitos Mononucleares , Mutagênese Sítio-Dirigida , Polimorfismo Genético , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
19.
PLoS One ; 12(7): e0180418, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28678835

RESUMO

Myotis rufoniger is a vesper bat in the genus Myotis. Here we report the whole genome sequence and analyses of the M. rufoniger. We generated 124 Gb of short-read DNA sequences with an estimated genome size of 1.88 Gb at a sequencing depth of 66× fold. The sequences were aligned to M. brandtii bat reference genome at a mapping rate of 96.50% covering 95.71% coding sequence region at 10× coverage. The divergence time of Myotis bat family is estimated to be 11.5 million years, and the divergence time between M. rufoniger and its closest species M. davidii is estimated to be 10.4 million years. We found 1,239 function-altering M. rufoniger specific amino acid sequences from 929 genes compared to other Myotis bat and mammalian genomes. The functional enrichment test of the 929 genes detected amino acid changes in melanin associated DCT, SLC45A2, TYRP1, and OCA2 genes possibly responsible for the M. rufoniger's red fur color and a general coloration in Myotis. N6AMT1 gene, associated with arsenic resistance, showed a high degree of function alteration in M. rufoniger. We further confirmed that the M. rufoniger also has bat-specific sequences within FSHB, GHR, IGF1R, TP53, MDM2, SLC45A2, RGS7BP, RHO, OPN1SW, and CNGB3 genes that have already been published to be related to bat's reproduction, lifespan, flight, low vision, and echolocation. Additionally, our demographic history analysis found that the effective population size of Myotis clade has been consistently decreasing since ~30k years ago. M. rufoniger's effective population size was the lowest in Myotis bats, confirming its relatively low genetic diversity.


Assuntos
Quirópteros/genética , Genoma , Substituição de Aminoácidos , Animais , Quirópteros/classificação , Variação Genética , Mutação , Filogenia
20.
J Biotechnol ; 126(3): 406-13, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16730829

RESUMO

Heat shock proteins (HSPs) play a central role in cell protection and repair upon stresses, such as that caused by heat and heavy metals. Copper sulfate inducibility of a pHhsp70 construct expressing the enhanced green fluorescent protein (EGFP) gene under the control of the exogenous human hsp70 promoter was tested in transfected CHSE 214 cells and transgenic zebrafish (Danio rerio). We developed a transient expression system, using mosaically transgenic zebrafish, which allows rapid analysis of transgenic expression. Transfected CHSE 214 cells which had been exposed to 250 nM and 2.5 microM copper sulfate for up to 24h showed increased EGFP expression in a dose-dependent manner. The 1.5 microM copper sulfate caused stronger EGFP fluorescence than the 1.0 microM copper sulfate in transgenic zebrafish. Most of the expression was spotty and was detected in the gills, dorsal and ventral retina, myotubes of the trunk, and skin epithelium. Transgenic zebrafish exposed to copper sulfate exhibited gross dysmorphogenesis, edema and trunk abnormalities, such as spinal lordosis, in vertebral development 5 days after fertilization. This transgenic zebrafish system was sensitive enough to detect copper sulfate at doses below the median lethal concentration (the LC50 was calculated to be 1.2 microM (95% confidence interval of 0.6-1.9 microM)). These results indicate that zebrafish could be useful transgenic biosensor systems for the detection of xenobiotic toxicants in the environment.


Assuntos
Sulfato de Cobre/farmacologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Regiões Promotoras Genéticas/fisiologia , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Mosaicismo , Regiões Promotoras Genéticas/efeitos dos fármacos
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