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1.
Zootaxa ; 4942(2): zootaxa.4942.2.9, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33757071

RESUMO

Anteholosticha sigmoidea (Foissner, 1982) Berger, 2003 was isolated from a wet soil sample collected on King George Island, Antarctica. Morphological observations and molecular phylogenetic analyses based on the gene sequences of small subunit ribosomal RNA (18S rRNA) were used to identify the species. Anteholosticha sigmoidea can be divided into two groups: group I (three populations described by Foissner 1982) and group II (described by Foissner 1984) based on the morphological differences. Group I differs from group II by the length of the midventral complex (65.1% vs. 52.5% of the cell length), the number of adoral membranelles (25-28 vs. 16-24), and the number of dorsal bristles in kinety 1 (16 bristles vs. nine bristles). Group I differs from the Antarctica population by the absence/presence of the collecting canals of the contractile vacuole and the number of macronuclear nodules (6-12 vs. 13-19). Group II differs from the Antarctica population by the number of macronuclear nodules (five to nine vs. 13-19); the arrangement of cortical granules (forming longitudinal rows vs. irregularly distributed); the length of the midventral complex (64.7% vs. 53.8% of cell length). In the phylogenetic analyses, A. sigmoidea was not nested with any species, and the gene tree indicated polyphyly of the genus Anteholosticha.


Assuntos
Cilióforos , Animais , Regiões Antárticas , Cilióforos/genética , DNA de Protozoário , Filogenia , RNA Ribossômico 18S/genética
2.
Eur J Protistol ; 71: 125641, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31639568

RESUMO

A new hypotrichous ciliate, Oxytricha seokmoensis sp. nov., was discovered in a soil from a forest in South Korea and described based on the observations of living and stained specimens. In addition, phylogenetic analyses were performed using the small subunit ribosomal RNA (18S rRNA) gene sequence. Morphologically, the new species is similar to the O. granulifera-complex in terms of ciliary structure and arrangement of cortical granules, but dorsal kineties 3 and 4 (not completely separated vs. separated) and macronuclear nodules in the cyst (separated vs. fused) differ. Oxytricha seokmoensis is most similar to O. pulvillus, but can be distinguished by the number of adoral membranelles (30-40 vs. 23-27), contractile vacuole (present vs. absent), number of left (27-37 vs. 17-25) and right (27-35 vs. 18-23) marginal cirri, and lepidosomes on the cyst surface (present vs. absent). In a phylogenetic tree, O. seokmoensis is distinctly separated from the O. granulifera clade, but is sister to the Paroxytricha clade. In addition, O. seokmoensis and P. longigranulosa have the smallest genetic difference (d = 0.015, 23 of 1579 nt difference). This close relationship is supported by incomplete dorsal kinety 3 fragmentation and separated macronuclear nodules in resting cysts.


Assuntos
Oxytricha/classificação , Filogenia , Oxytricha/citologia , Oxytricha/genética , Oxytricha/crescimento & desenvolvimento , RNA Ribossômico 18S/genética , Especificidade da Espécie
3.
Mol Phylogenet Evol ; 139: 106538, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31220579

RESUMO

In a study of ciliate diversity, we collected two new species of the genera Australothrix and Holostichides. Based on nuclear ribosomal genes, our study shows that these two genera are genetically non-monophyletic. To clarify the issues of the non-monophyly, we reexamined type material of H. heterotypicus, H. terrae, and Birojimia soyaensis. Based on multigene and morphometric analyses, Australothrix and Holostichides are clearly non-monophyletic even in mitochondrial CO1 gene trees. The multigene analyses show a clade composed of A. lineae sp. nov., H. terrae, and B. soyaensis, suggesting that a cytopharynx with argyrophilic structures might be their synapomorphy. A list of species with this type of cytopharynx is provided for further studies to either accept or reject this hypothesis. Based on the reexamination, we discriminate the morphologically nearly identical (cryptic/sibling) species H. obliquocirratus sp. nov. from H. heterotypicus and they show significant genetic dissimilarities in the multigene trees. They showed only few morphological (non-quantitative) differences and thus distinguishing them morphologically needs careful investigation.


Assuntos
Cilióforos/classificação , Cilióforos/genética , Genes de Protozoários , Filogenia , Cilióforos/ultraestrutura , Complexo IV da Cadeia de Transporte de Elétrons/genética , Funções Verossimilhança , RNA Ribossômico/genética
4.
J Eukaryot Microbiol ; 66(5): 740-751, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30746815

RESUMO

Two new soil oxytrichids, Australocirrus rubrus n. sp. and Notohymena gangwonensis n. sp., were discovered from South Korea. Morphologically, A. rubrus shares many features with A. australis, and these two species form a single clade in a molecular tree based on nuclear small subunit ribosomal RNA (SSU rRNA) gene sequences. Australocirrus rubrus mainly differs from A. australis in the color (citrine color vs. reddish) and distribution of the cortical granules. Additionally, we confirm that the genus Australocirrus is not a monophyletic group, as A. shii is separated from the clade comprising the other Australocirrus species, being clustered instead with other taxa. Notohymena gangwonensis n. sp. mainly differs from its congeners by the following combination of features: irregularly distributed cortical granules (vs. arranged in groups associated with cirri and dorsal kineties), variable four or five (usually four) transverse cirri (vs. invariable five), and the anteriormost pretransverse cirrus V/2 on 13.2-16.1% of cell length (vs. on or above 18.9% of cell length). Currently, there are no available gene sequences for members of the genus Notohymena, thus we provide SSU rRNA gene sequences from the new species of Notohymena, as well as detailed morphological descriptions of the novel species.


Assuntos
Cilióforos/crescimento & desenvolvimento , Cilióforos/isolamento & purificação , Filogenia , Cilióforos/classificação , Cilióforos/genética , DNA de Protozoário/genética , RNA Ribossômico 18S/genética , República da Coreia , Solo/parasitologia
5.
Arch Toxicol ; 91(12): 4009-4015, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28634823

RESUMO

Discrepant incidence has been reported regarding the incidence of herb-induced liver injury (HILI). To address the growing worldwide concern of HILI, we evaluated the risk of HILI in a nationwide prospective study. Between April 2013 and January 2016, 1001 inpatients (360 males and 641 females) from 10 tertiary hospitals throughout South Korea were treated with herbal drugs and had their liver enzymes periodically measured. A total of six patients met the criteria for HILI with RUCAM scores ranging from 4 to 7. All these participants were women and developed the hepatocellular type of HILI. One HILI participant met the criteria for Hy's law; however, none of six cases presented clinical symptoms related to liver injury. This is the first nationwide prospective study that estimated the extent of the incidence of HILI [total: 0.60%, 95% confidence interval (CI) 0.12-1.08; women: 0.95%, 95% CI 0.19-1.68] and described its features in hospitalized participants.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Medicamentos de Ervas Chinesas/efeitos adversos , Fígado/enzimologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Feminino , Humanos , Incidência , Fígado/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , República da Coreia/epidemiologia
6.
J Eukaryot Microbiol ; 64(6): 873-884, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28459502

RESUMO

Two new urostylid species, Holostichides heterotypicus n. sp. and Holosticha muuiensis n. sp., were discovered in South Korea. Morphological and phylogenetic analyses were carried out to confirm that these species are new to science. Holostichides heterotypicus is mainly characterized by the following combination of features: 110-205 µm long in vivo; 5-10 frontoterminal cirri; 6-8 midventral pairs with 2-3 midventral cirral rows; cortical granules present; four bipolar dorsal kineties; and 6-9 caudal cirri. Ontogenetic features of H. heterotypicus are similar to those of H. typicus. Phylogenetic analyses revealed that H. heterotypicus was distantly separated from bakuellid genera Apobakuella, Bakuella, Metaurostylopsis, and Neobakuella. This result is supported by the following features: transverse cirri (present in the other four bakuellids vs. absent in Holostichides) and caudal cirri (absent in the other four bakuellids vs. present in Holostichides). Holosticha muuiensis n. sp. is mainly distinguished from its congeners by the following combination of features: 100-185 long in vivo; shortened undulating membrane; cortical granules lacking; contractile vacuole absent; 51-66 adoral zone of membranelles; 42-60 macronuclear nodules; and five bipolar dorsal kineties. In the phylogenetic tree, Holosticha muuiensis n. sp. clustered with a Holosticha group (containing Holosticha diademata, Holosticha foissneri, and Holosticha heterofoissneri).


Assuntos
Cilióforos/classificação , Filogenia , Cilióforos/citologia , Cilióforos/genética , Cilióforos/isolamento & purificação , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Microscopia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , República da Coreia , Análise de Sequência de DNA
7.
FEBS Lett ; 586(19): 3493-9, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22967894

RESUMO

Based on the fact that the amino acid sequence of sulfiredoxin (Srx), already known as a redox-dependent sulfinic acid reductase, showed a high sequence homology with that of ParB, a nuclease enzyme, we examined the nucleic acid binding and hydrolyzing activity of the recombinant Srx in Arabidopsis (AtSrx). We found that AtSrx functions as a nuclease enzyme that can use single-stranded and double-stranded DNAs as substrates. The nuclease activity was enhanced by divalent cations. Particularly, by point-mutating the active site of sulfinate reductase, Cys (72) to Ser (AtSrx-C72S), we demonstrate that the active site of the reductase function of AtSrx is not involved in its nuclease function.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Cátions Bivalentes/farmacologia , DNA de Plantas/genética , Desoxirribonucleases/genética , Desoxirribonucleases/metabolismo , Dados de Sequência Molecular , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Ácidos Sulfínicos/metabolismo
8.
Mol Cells ; 33(1): 27-33, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22228209

RESUMO

Peroxiredoxins (Prxs), which are classified into three isotypes in plants, play important roles in protection systems as peroxidases or molecular chaperones. The three Prx isotypes of Chinese cabbage, namely C1C-Prx, C2C-Prx, and C-PrxII, have recently been identified and characterized. The present study compares their molecular properties and biochemical functions to gain insights into their concerted roles in plants. The three Prx isotype genes were differentially expressed in tissue- and developmental stage-specific manners. The transcript level of the C1C-Prx gene was abundant at the seed stage, but rapidly decreased after imbibitions. In contrast, the C2C-Prx transcript was not detected in the seeds, but its expression level increased at germination and was maintained thereafter. The C-PrxII transcript level was mild at the seed stage, rapidly increased for 10 days after imbibitions, and gradually disappeared thereafter. In the localization analysis using GFP-fusion proteins, the three isotypes showed different cellular distributions. C1C-Prx was localized in the cytosol and nucleus, whereas C2C-Prx and C-Prx were found mainly in the chloroplast and cytosol, respectively. In vitro thiol-dependent antioxidant assays revealed that the relative peroxidase activities of the isotypes were CPrxII > C2C-Prx > C1C-Prx. C1C-Prx and C2C-Prx, but not C-PrxII, prevented aggregation of malate dehydrogenase as a molecular chaperone. Taken together, these results suggest that the three isotypes of Prx play specific roles in the cells in timely and spatially different manners, but they also cooperate with each other to protect the plant.


Assuntos
Brassica/enzimologia , Peroxirredoxinas/metabolismo , Sequência de Aminoácidos , Brassica/genética , Brassica/metabolismo , Isoenzimas , Chaperonas Moleculares , Dados de Sequência Molecular
9.
Plant Sci ; 181(2): 119-24, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21683876

RESUMO

Peroxiredoxins are antioxidative enzymes that catalyze the reduction of alkyl hydroperoxides to alcohols and hydrogen peroxide to water. 1-Cys peroxiredoxins (1-Cys Prxs) perform important roles during late seed development in plants. To characterize their biochemical functions in plants, a 1Cys-Prx gene was cloned from a Chinese cabbage cDNA library and designated as "C1C-Prx". Glutamine synthetase (GS) protection and hydrogen peroxide reduction assays indicated that C1C-Prx was functionally active as a peroxidase. Also C1C-Prx prevented the thermal- or chemical-induced aggregation of malate dehydrogenase and insulin. Hydrogen peroxide treatment changed the mobility of C1C-Prx on a two-dimensional gel, which implies overoxidation of the conserved Cys residue. Furthermore, after overoxidation, the chaperone activity of C1C-Prx increased approximately two-fold, but its peroxidase activity decreased to the basal level of the reaction mixture without enzyme. However, according to the structural analysis using far-UV circular dichroism spectra, intrinsic tryptophan fluorescence spectra, and native-PAGE, overoxidation did not lead to a conformational change in C1C-Prx. Therefore, our results suggest that 1-Cys Prxs function not only to relieve mild oxidative stresses but also as molecular chaperones under severe conditions during seed germination and plant development, and that overoxidation controls the switch in function of 1-Cys-Prxs from peroxidases to molecular chaperones.


Assuntos
Brassica/metabolismo , Chaperonas Moleculares/metabolismo , Peroxirredoxinas/metabolismo , Sementes/fisiologia , Sequência de Aminoácidos , Antioxidantes/metabolismo , Brassica/enzimologia , Brassica/genética , Cisteína/química , Flores/enzimologia , Flores/genética , Flores/metabolismo , Dosagem de Genes , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Peróxido de Hidrogênio/química , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Dados de Sequência Molecular , Estresse Oxidativo , Peroxirredoxinas/química , Peroxirredoxinas/genética , Dormência de Plantas/fisiologia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Ligação Proteica , Proteínas Recombinantes , Sementes/enzimologia , Sementes/genética , Alinhamento de Sequência
10.
J Korean Neurosurg Soc ; 46(5): 437-42, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20041053

RESUMO

OBJECTIVE: To characterize perioperative biomechanical changes after thoracic spine surgery. METHODS: Fifty-eight patients underwent spinal instrumented fusions and simple laminectomies on the thoracolumbar spine from April 2003 to October 2008. Patients were allocated to three groups; namely, the laminectomy without fusion group (group I, n = 17), the thoracolumbar fusion group (group II, n = 27), and the thoracic spine fusion group (group III, n = 14). Sagittal (ADS) and coronal (ADC) angles for adjacent segments were measured from two disc spaces above lesions at the upper margins, to two disc spaces below lesions at the lower margins. Sagittal (TLS) and coronal (TLC) angles of the thoracolumbar junction were measured from the lower margin of the 11th thoracic vertebra body to the upper margin of the 2nd lumbar vertebra body on plane radiographs. Adjacent segment disc heights and disc signal changes were determined using simple spinal examinations and by magnetic resonance imaging. Clinical outcome indices were determined using a visual analog scale. RESULTS: The three groups demonstrated statistically significant differences in terms of angle changes by ANOVA (p < 0.05). All angles in group I showed significantly smaller angles changes than in groups II and III by Turkey's multiple comparison analysis. Coronal Cobb's angles of the thoracolumbar spine (TLC) were not significantly different in the three groups. CONCLUSION: Postoperative sagittal balance is expected to change in the adjacent and thoracolumbar areas after thoracic spine fusion. However, its prevalence seems to be higher when the thoracolumbar spine is included in instrumented fusion.

11.
Exp Mol Med ; 39(2): 149-59, 2007 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-17464176

RESUMO

We demonstrated previously that Coptidis rhizoma extract (CRE) prevented S-nitroso-N-acetylpenicillamine-induced apoptotic cell death via the inhibition of mitochondrial membrane potential disruption and cytochrome c release in RINm5F (RIN) rat insulinoma cells. In this study, the preventive effects of CRE against cytokine-induced beta-cell death was assessed. Cytokines generated by immune cells infiltrating pancreatic islets are crucial mediators of beta-cell destruction in insulin-dependent diabetes mellitus. The treatment of RIN cells with IL-1beta and IFN-gamma resulted in a reduction of cell viability. CRE completely protected IL-1beta and IFN-gamma-mediated cell death in a concentration-dependent manner. Incubation with CRE induced a significant suppression of IL-1beta and IFN-gamma-induced nitric oxide (NO) production, a finding which correlated well with reduced levels of the iNOS mRNA and protein. The molecular mechanism by which CRE inhibited iNOS gene expression appeared to involve the inhibition of NF-kappaB activation. The IL-1beta and IFN-gamma-stimulated RIN cells showed increases in NF-kappaB binding activity and p65 subunit levels in nucleus, and IkappaB alpha degradation in cytosol compared to unstimulated cells. Furthermore, the protective effects of CRE were verified via the observation of reduced NO generation and iNOS expression, and normal insulin-secretion responses to glucose in IL-1beta and IFN-gamma-treated islets.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/efeitos dos fármacos , Interferon gama/farmacologia , Interleucina-1beta/farmacologia , NF-kappa B/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Coptis chinensis , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Proteínas I-kappa B/metabolismo , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/enzimologia , Masculino , Inibidor de NF-kappaB alfa , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
12.
Int J Mol Med ; 19(3): 535-40, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17273805

RESUMO

Cytokines produced by immune cells infiltrating pancreatic islets are important mediators of beta-cell destruction in insulin-dependent diabetes mellitus. Cytokines stimulate an inducible form of nitric oxide synthase (iNOS) expression and nitric oxide (NO) production, leading to insulin insufficiency. In the present study, the effects of Artemisia capillaris extract (ACE) on cytokine-induced beta-cell damage were examined. Treatment of RINm5F (RIN) rat insulinoma cells with interleukin-1beta (IL-1beta) and interferon-gamma (IFN-gamma) induced cell damage. ACE completely protected IL-1beta and IFN-gamma-mediated cytotoxicity in a concentration-dependent manner. Incubation with ACE resulted in a significant reduction in IL-1beta and IFN-gamma-induced NO production, a finding that correlated well with reduced levels of the iNOS mRNA and protein. The molecular mechanism by which ACE inhibited iNOS gene expression appeared to involve the inhibition of NF-kappaB activation. The IL-1beta and IFN-gamma-stimulated RIN cells showed increases in NF-kappaB binding activity and p65 subunit levels in the nucleus, and IkappaBalpha degradation in cytosol compared to unstimulated cells. Furthermore, ACE restored the cytokine-induced inhibition of insulin release from isolated islets. These results suggest that ACE protects beta-cells by suppressing NF-kappaB activation.


Assuntos
Artemisia/metabolismo , Interferon gama/farmacologia , Interleucina-1beta/farmacologia , Óxido Nítrico/biossíntese , Extratos Vegetais/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Insulina/metabolismo , Secreção de Insulina , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos
13.
Biol Pharm Bull ; 29(6): 1082-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16754997

RESUMO

Radix Paeoniae Alba has been used as a constituent of herbal medicine prescriptions for the treatment of inflammation, cancer, and other diseases. The aim of this study was to investigate the mechanism of Radix Paeoniae Alba extract (RPAE)-induced apoptosis in HL-60 leukemic cells. We observed that RPAE induced apoptotic changes in a dose-dependent manner, which was confirmed by DNA fragmentation and poly-(ADP-ribose) polymerase (PARP) cleavage. We also found release of cytochrome c from mitochondria to the cytosol in RPAE-treated HL-60 cells. The caspases, caspase-9 and -3, but not caspase-8, were found to be activated in response to RPAE treatment, and the caspase-3 inhibitor, Ac-DEVD-CHO, and the caspase-9 inhibitor, z-LEHD-FMK, but not the caspase-8 inhibitor, z-IETD-FMK, attenuated RPAE-induced DNA fragmentation and PARP cleavage. These results suggest that RPAE-induced apoptosis is stimulated by the release of cytochrome c to the cytosol, by procaspase-9 processing, and via a caspase-3 dependent mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Citocromos c/metabolismo , Paeonia/química , Extratos Vegetais/farmacologia , Western Blotting , Inibidores de Caspase , Sobrevivência Celular/efeitos dos fármacos , Citosol/efeitos dos fármacos , Citosol/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel de Ágar , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Células HL-60 , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Extratos Vegetais/isolamento & purificação , Poli(ADP-Ribose) Polimerases/metabolismo , Fatores de Tempo
14.
World J Gastroenterol ; 11(7): 943-7, 2005 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-15742393

RESUMO

AIM: To clarify the mechanism underlying the anti-mutagenic and anti-cancer activities of Scorpio water extract (SWE). METHODS: Human hepatoma HepG2 cells were incubated with various concentrations of SWE. After 24-h incubation, cytotoxicity and apoptosis evaluations were determined by MTT and DNA fragmentation assay, respectively. After treatment with SWE, mitochondrial membrane potential (MMP) was determined by measuring the retention of the dye 3,3'-dihexyloxacarbocyanine (DiOC(6)(3)) and the protein expression including cytochrome C and poly-(ADP-ribose) polymerase (PARP) were measured by Western blotting. Caspase-3 and -9 enzyme activities were measured using specific fluorescence dyes such as Ac-DEVD-AFC and Ac-LEHD-AFC. RESULTS: We found that treatment with SWE induced apoptosis as confirmed by discontinuous DNA fragmentation in cultured human hepatoma HepG2 cells. Our investigation also showed that SWE-induced apoptosis of HepG2 cells were associated with intracellular events including disruption of MMP, increased translocation of cytochrome C from mitochondria to cytosol, activation of caspase-3, and PARP. Pre-treatment of N-acetyl-Asp-Glu-Val-Asp-CHO (Ac-DEVD-CHO), a caspase-3 specific inhibitor, or cyclosporin A (CsA), an inhibitor of MMP disruption, completely abolished SWE-induced DNA fragmentation. CONCLUSION: These results suggest that SWE possibly causes mitochondrial damage, leading to cytochrome C release into cytosol and activation of caspases resulting in PARP cleavage and execution of apoptotic cell death in HepG2 cells. These results further suggest that Scorpio may be a valuable agent of therapeutic intervention of human hepatomas.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Hepáticas , Caspase 3 , Caspase 9 , Inibidores de Caspase , Caspases/metabolismo , Linhagem Celular Tumoral , Ciclosporina/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Citocromos c/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Oligopeptídeos/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo
15.
Life Sci ; 76(8): 917-29, 2005 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-15589968

RESUMO

Coptidis rhizoma (CR) is a herb used in many traditional prescriptions against diabetes mellitus in Asia for centuries. Our purpose was to determine the protective effect and its action mechanism of CR on the cytotoxicity of pancreatic beta-cells. Nitric oxide (NO) is believed to play a key role in the process of pancreatic beta-cell destruction leading to insulin-dependent diabetes mellitus (IDDM). Exposure of RINm5F cells to chemical NO donor such as S-nitroso-N-acetylpenicillamine (SNAP) induced apoptotic events such as the disruption of mitochondrial membrane potential (Deltapsim), cytochrome c release from mitochondria, activation of caspase-3, poly (ADP-ribose) polymerase cleavage and DNA fragmentation. Also, exposure of SNAP led to LDH release into medium, one of the necrotic events. However, pretreatment of RINm5F cells with CR extract protected both apoptosis and necrosis through the inhibition of Deltapsim disruption in SNAP-treated RINm5F cells. In addition, rat islets pretreated with CR extract retained the insulin-secretion capacity even after the treatment with IL-1beta. These results suggest that CR may be a candidate for a therapeutic or preventing agent against IDDM.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Necrose/prevenção & controle , Doadores de Óxido Nítrico/farmacologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Animais , Linhagem Celular Tumoral , Coptis chinensis , Relação Dose-Resposta a Droga , Insulinoma/tratamento farmacológico , Insulinoma/metabolismo , Insulinoma/patologia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , L-Lactato Desidrogenase/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Ratos , Ratos Sprague-Dawley
16.
Immunopharmacol Immunotoxicol ; 24(3): 441-53, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12375739

RESUMO

A human hepatoma cell line, Hep G2 cell, is reliable for the study of alcohol-induced hepatotoxicity. In this study, we investigated the effect of an aqueous extract of Artemisia capillaris Thunb (Compositae) plant (AC) on ethanol (EtOH)-induced cytotoxicity in Hep G2 cells. AC (0.5-5 microg/mL) inhibited the secretion of EtOH-induced interluekin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha). AC also inhibited the EtOH-, IL-1alpha-, and TNF-alpha-induced cytotoxicity. Furthermore, we found that AC inhibited the EtOH-induced apoptosis of Hep G2 cells. These results suggest that AC may prevent the EtOH-induced cytotoxicity through inhibition of the apoptosis of Hep G2 cells.


Assuntos
Artemisia , Etanol/toxicidade , Interleucina-1/metabolismo , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células Tumorais Cultivadas
17.
Clin Chim Acta ; 318(1-2): 113-20, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11880120

RESUMO

BACKGROUND: Euonymus alatus (EA) has been used for tumor therapy. However, it is still unclear how this herb prevents the diseases in experimental models. Nitric oxide (NO) as a potent macrophage-derived effector molecule against a variety of tumors has received increasing attention. METHODS: Using mouse peritoneal macrophages, we have examined the mechanism by which EA regulates NO production. RESULTS: When EA was used in combination with recombinant interferon-gamma (rIFN-gamma), there was a marked cooperative induction of NO production. However, EA had no effect on NO production by itself. The increased production of NO from rIFN-gamma plus EA-stimulated cells was almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappa B (NF-kappaB). Furthermore, treatment of peritoneal macrophages with rIFN-gamma plus EA caused a significant increase in tumor necrosis factor-alpha (TNF-alpha) production. PDTC also decreased the effects of EA on TNF-alpha production significantly. CONCLUSIONS: EA increases the production of NO and TNF-alpha by rIFN-gamma-primed macrophages and suggest that NF-kappaB plays a critical role in mediating these effects of EA.


Assuntos
Euonymus/química , Macrófagos Peritoneais/enzimologia , Óxido Nítrico Sintase/metabolismo , Animais , Western Blotting , Endotoxinas/farmacologia , Ativação Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Técnicas In Vitro , Indicadores e Reagentes , Interferon gama/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase Tipo II , Extratos Vegetais/antagonistas & inibidores , Extratos Vegetais/farmacologia , Pirrolidinas/farmacologia , Proteínas Recombinantes , Transdução de Sinais/efeitos dos fármacos , Tiocarbamatos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , ômega-N-Metilarginina/farmacologia
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