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1.
Mol Nutr Food Res ; 54(9): 1318-28, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20397191

RESUMO

Although eupafolin, a flavone found in Artemisia princeps Pampanini, has been shown to inhibit the growth of several human cancer cells, its mode of action is poorly understood. In this study, we investigated the pro-apoptotic activities of eupafolin in human cervical carcinoma HeLa cells. It was found that eupafolin induced apoptosis in a dose-dependent manner, as evidenced by DNA fragmentation and the accumulation of positive cells for annexin V. In addition, eupafolin triggered the activations of caspases-3, -6, -7, -8, and -9 and the cleavages of their substrates, such as, poly (ADP-ribose) polymerase and lamin A/C. Furthermore, treatment with eupafolin resulted in a loss of mitochondrial membrane potential (DeltaPsi(m)), increased the release of cytochrome c to the cytosol, and altered the expression levels of B-cell lymphoma 2 (Bcl-2) family proteins. Interestingly, caspase-8, an initiator caspase, was activated after the loss of DeltaPsi(m) and the activations of caspases-3 and -9. Moreover, treatment with z-DEVD-fmk (a specific caspase-3 inhibitor) and the overexpression of Bcl-2 prevented eupafolin-stimulated caspase-8 activation. Altogether, these results suggest that the eupafolin-induced apoptosis in HeLa cells is mediated by caspase-dependent pathways, involving caspases-3, -9, and -8, which are initiated by the Bcl-2-dependent loss of DeltaPsi(m).


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Artemisia/química , Flavonas/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Caspases/metabolismo , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Feminino , Flavonas/química , Flavonas/isolamento & purificação , Células HeLa , Humanos , Concentração Inibidora 50 , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Permeabilidade/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
2.
Int Immunopharmacol ; 9(11): 1323-31, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19666143

RESUMO

It is well known that pro-inflammatory mediators like nitric oxide (NO), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) contribute to the courses of many inflammatory diseases. In the present study, the authors investigated the anti-inflammatory effects of pseudocoptisine, a quaternary alkaloid with a benzylisoquinoline skeleton, which was isolated from the tubers of Corydalis turtschaninovii by examining its inhibitory effects on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells. Pseudocoptisine caused dose-dependent reductions in the levels of inducible nitric oxide (iNOS) and cyclooxygenase-2 (COX-2) at both protein and mRNA levels and concomitant decreases in PGE(2) and NO production. In addition, it was found that pseudocoptisine suppressed the production and mRNA expressions of inflammatory cytokines, such as, TNF-alpha and IL-6. Furthermore, molecular data revealed that pseudocoptisine inhibited the LPS-stimulated DNA binding activity and the transcription activity of nuclear factor-kappa B (NF-kappaB). Moreover, this effect was accompanied by decreases in the phosphorylation of inhibitory kappaB (IkappaB)-alpha and in the subsequent blocking of p65 subunit of NF-kappaB translocation to the nucleus. In addition, pseudocoptisine dose-dependently inhibited the phosphorylations of ERK and p38. Taken together, these results suggest that pseudocoptisine reduces levels of the pro-inflammatory mediators, such as, iNOS, COX-2, TNF-alpha, and IL-6 through the inhibition of NF-kappaB activation via the suppression of ERK and p38 phosphorylation in RAW 264.7 cells. These findings reveal in part the molecular basis for the anti-inflammatory properties of pseudocoptisine.


Assuntos
Benzilisoquinolinas/farmacologia , Citocinas/metabolismo , Dinoprostona/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/efeitos dos fármacos , NF-kappa B/metabolismo , Animais , Benzilisoquinolinas/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Corydalis/química , Ciclo-Oxigenase 2 , Regulação para Baixo , Proteínas I-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Tubérculos/química , Compostos de Amônio Quaternário/química
3.
Biol Pharm Bull ; 29(12): 2436-41, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17142978

RESUMO

A study was conducted to determine whether the ethanol extract of the roots of Brassica rapa (EBR) ameliorates cisplatin-induced nephrotoxicity in terms of oxidative stress, as characterized by lipid peroxidation, reactive oxygen species (ROS) production, and glutathione (GSH) depletion in LLC-PK1 cells. Pretreatment of cells with EBR prevented cisplatin-induced decreases in cell viability and cellular GSH content. The effect of EBR was then investigated in rats given EBR for 14 d before cisplatin administration. A single dose of cisplatin (7 mg/kg, i.p.) caused kidney damage manifested by an elevation in blood urea nitrogen (BUN), serum creatinine, and urine lactate dehydrogenase (LDH) levels. Also, renal tissue from cisplatin-treated rats showed a significant increase in malondialdehyde (MDA) production, and in the activities of aldehyde oxidase (AO) and xanthine oxidase (XO). Moreover, a significant decrease in the activities of antioxidant enzymes, such as, glutathione peroxidase (GPx), superoxide dismutase (SOD) and catalase (CAT) was observed in cisplatin-treated rats versus saline-treated normal group. In contrast, rats given EBR showed lower blood levels of BUN and creatinine, and of urinary LDH. Moreover, EBR prevented the rise of MDA production and the induction of AO and XO activities. This extract also recovered the reduced activities of GPx, SOD and CAT. Taken together, our data indicate that the ethanol extract of the roots of Brassica rapa (EBR) has a protective effect against cisplatin-induced nephrotoxicity because it attenuates oxidative stress.


Assuntos
Antineoplásicos/toxicidade , Brassica rapa/química , Cisplatino/toxicidade , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Animais , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/metabolismo , Rim/citologia , Rim/metabolismo , L-Lactato Desidrogenase/urina , Células LLC-PK1 , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Suínos
4.
Planta Med ; 72(13): 1181-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16924582

RESUMO

During our efforts to find bioactive natural products with anti-inflammatory activity, we isolated gigantol from the whole plants of Cymbidium goeringii (Orchidaceae) by activity-guided chromatographic fractionation. Gigantol was found to have potent inhibitory effects on LPS-induced nitric oxide (NO) and prostaglandin E (2) (PGE (2)) production in RAW 264.7 cells. Consistent with these findings, gigantol suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in RAW 264.7 cells in a concentration-dependent manner. Our data also indicate that gigantol is a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) release and influenced the mRNA expression levels of these cytokines in a dose-dependent manner. Furthermore, a reporter gene assay for nuclear factor kappa B (NF-kappaB) and an electromobility shift assay (EMSA) demonstrated that gigantol effectively inhibited the activation of NF-kappaB, which is necessary for the expression of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6. Thus, our studies suggest that gigantol inhibits LPS-induced iNOS and COX-2 expression by blocking NF- kappaB activation.


Assuntos
Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Guaiacol/análogos & derivados , Macrófagos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Orchidaceae/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Bibenzilas , Linhagem Celular , Fracionamento Químico , Dinoprostona/biossíntese , Ensaio de Desvio de Mobilidade Eletroforética , Genes Reporter , Guaiacol/química , Guaiacol/isolamento & purificação , Guaiacol/farmacologia , Interleucina-1beta/biossíntese , Interleucina-6/biossíntese , Lipopolissacarídeos/antagonistas & inibidores , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
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