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1.
Environ Toxicol ; 32(8): 2070-2084, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28370894

RESUMO

Cigarette smoke exposure activates several cellular mechanisms predisposing to atherosclerosis, including oxidative stress, dyslipidemia, and vascular inflammation. Antrodia camphorata, a renowned medicinal mushroom in Taiwan, has been investigated for its antioxidant, anti-inflammatory, and antiatherosclerotic properties in cigarette smoke extracts (CSE)-treated vascular smooth muscle cells (SMCs), and ApoE-deficient mice. Fermented culture broth of Antrodia camphorata (AC, 200-800 µg/mL) possesses effective antioxidant activity against CSE-induced ROS production. Treatment of SMCs (A7r5) with AC (30-120 µg/mL) remarkably ameliorated CSE-induced morphological aberrations and cell death. Suppressed ROS levels by AC corroborate with substantial inhibition of CSE-induced DNA damage in AC-treated A7r5 cells. We found CSE-induced apoptosis through increased Bax/Bcl-2 ratio, was substantially inhibited by AC in A7r5 cells. Notably, upregulated SOD and catalase expressions in AC-treated A7r5 cells perhaps contributed to eradicate the CSE-induced ROS generation, and prevents DNA damage and apoptosis. Besides, AC suppressed AP-1 activity by inhibiting the c-Fos/c-Jun expressions, and NF-κB activation through inhibition of I-κBα degradation against CSE-stimulation. This anti-inflammatory property of AC was accompanied by suppressed CSE-induced VEGF, PDGF, and EGR-1 overexpressions in A7r5 cells. Furthermore, AC protects lung fibroblast (MRC-5) cells from CSE-induced cell death. In vivo data showed that AC oral administration (0.6 mg/d/8-wk) prevents CSE-accelerated atherosclerosis in ApoE-deficient mice. This antiatherosclerotic property was associated with increased serum total antioxidant status, and decreased total cholesterol and triacylglycerol levels. Thus, Antrodia camphorata may be useful for prevention of CSE-induced oxidative stress and diseases. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 2070-2084, 2017.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Antrodia/química , Apoptose/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Nicotiana/química , Espécies Reativas de Oxigênio/metabolismo , Fumaça/efeitos adversos , Animais , Apolipoproteínas E/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Linhagem Celular , Meios de Cultura/farmacologia , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Inflamação/metabolismo , Pulmão/citologia , Camundongos , Músculo Liso Vascular/patologia , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Produtos do Tabaco , Fator de Transcrição AP-1/metabolismo
2.
J Ethnopharmacol ; 153(2): 499-510, 2014 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-24631961

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The medicinal mushroom Antrodia salmonea has been used as a traditional Chinese medicine and has demonstrated antioxidant and anti-inflammatory effects. MATERIALS AND METHODS: In the present study, we examined the anti-tumor activity of the fermented culture broth of Antrodia salmonea (AS) in vitro and in vivo and revealed its underlying molecular mechanism of action. RESULTS: Treatment of human promyelocytic leukemia (HL-60) cells with AS (50-150 µg/mL) significantly reduced cell viability and caused G1 arrest via the inhibition of cell-cycle regulatory proteins, including cyclin D1, CDK4, cyclin E, cyclin A, and phosphorylated retinoblastoma protein (p-Rb). Furthermore, AS treatment induced apoptosis, which was associated with DNA fragmentation, followed by a sequence of events, including intracellular ROS generation; mitochondrial dysfunction; Fas ligand activation; cytochrome c release; caspase-3, -8, -9, and PARP activation; and Bcl-2/Bax dysregulation. The results of the in vitro study suggested that AS-induced apoptosis in HL-60 cells was mediated by both the mitochondrial and death receptor pathways. Furthermore, we found that AS treatment was effective in delaying tumor incidence in HL-60 xenografted nude mice and reducing tumor burden. CONCLUSIONS: To the best of our knowledge, this is the first report confirming the anti-tumor activity of this potentially beneficial mushroom against human promyelocytic leukemia.


Assuntos
Antineoplásicos/farmacologia , Antrodia , Apoptose/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Leucemia Promielocítica Aguda/tratamento farmacológico , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/uso terapêutico , Antrodia/isolamento & purificação , Apoptose/fisiologia , Linhagem Celular , Relação Dose-Resposta a Droga , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/fisiologia , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
3.
Food Chem Toxicol ; 66: 150-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24480039

RESUMO

Antrodia salmonea is well known in Taiwan as a beneficial mushroom. In the present study, we investigated the antioxidant activity of whole fermented broth (AS), filtrate (ASF), and mycelia (ASM) of A. salmonea using different antioxidant models. Furthermore, the effect of A. salmonea on AAPH-induced oxidative hemolysis of human erythrocytes and CuSO4-induced oxidative modification of human low-density lipoproteins (LDLs) was examined. We found that the AS, ASF, and ASM possess effective antioxidant activity against various oxidative systems including superoxide anion scavenging, reducing power, metal chelation, and DPPH radical scavenging. Further, AAPH-induced oxidative hemolysis in erythrocytes was prevented by AS, ASF, and ASM. Notably, AS, ASF, and ASM appear to possess powerful antioxidant activities against CuSO4-induced oxidative modification of LDL as assessed by malondialdehyde (MDA) formation, cholesterol degradation, and the relative electrophoretic mobility of oxidized LDL. It is noteworthy that AS had comparatively strong antioxidant ability compared to ASF or ASM, which is well correlated with the content of their total polyphenols. Thus, A. salmonea may exert antioxidant properties and offer protection from atherogenesis.


Assuntos
Antioxidantes/farmacologia , Antrodia/química , Eritrócitos/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Quelantes/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Hemólise , Humanos
4.
Bioorg Med Chem ; 18(7): 2575-85, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20338768

RESUMO

Allostery in the binding of peptides to DNA has been studied by quantitative DNase I footprinting using four newly designed peptides containing the XP(Hyp)RK motif and N-methylpyrrole (Py) moieties. Apparent binding constants in the micromolar range as well as Hill coefficients were determined for each peptide. The results, together with previous studies on five other peptides support the proposal that interaction network cooperativity is highly preferred in DNA-peptide interactions that involve multiple recognition sites. It is envisaged that interstrand bidentate interactions participate in the relay of conformational changes between recognition sites on the complementary strands. Models for interpreting DNA allostery based upon interaction networks are outlined. Circular dichroism experiments involving the titration of peptides against a short oligonucleotide duplex indicate that some of these peptides bind in a dimeric manner to DNA via the minor groove, inducing characteristic conformational changes. These insights should prompt the design of new DNA-binding peptides for investigating allosteric interactions between peptides and DNA, as well as novel interaction networks, and ultimately may shed light upon the fundamental chemical rules that govern allostery in more complex biological process such as DNA-protein interaction networks.


Assuntos
DNA/química , Peptídeos/química , Autorradiografia , Dicroísmo Circular , Pegada de DNA , Desoxirribonuclease I/química , Ligantes , Oligonucleotídeos/química , Ligação Proteica , Conformação Proteica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Relação Estrutura-Atividade
5.
J Biosci Bioeng ; 105(2): 97-105, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18343334

RESUMO

Xylose from rice straw hemicellulose hydrolysate was fermented for xylitol production using Candida subtropicalis WF79 cells immobilized in polyacrylic hydrogel thin films of 200 mum thickness. Cell immobilization was conducted by first suspending the yeast cells in a mixture of 2-hydroxyethyl methacrylate (HEMA, hydrophilic monomer), polyethylene glycol diacrylate (PEG-DA, crosslinking agent), and benzoin isopropyl ether (photoinitiator). The mixture was then allowed to form polyacrylic hydrogel thin films, between two pieces of glass sheets, by UV-initiated photopolymerization. The hemicellulose of rice straw was hydrolyzed using dilute sulfuric acid at 126 degrees C. The hydrolysate was neutralized with calcium hydroxide. After separating the solid residues and calcium sulfate precipitates by filtration, the hydrolysate was treated with charcoal to partially remove potential inhibitory substances, followed by vacuum concentration to obtain solutions of desired xylose concentrations for yeast fermentation. The thin films with immobilized yeast cells were submerged in the xylose solution from rice straw hydrolysate for fermentation in an Erlenmeyer flask. The maximum yield was 0.73 g of xylitol per gram of xylose consumed. In the 52.5-day long durability test, after 40 d of repeated batchwise operation, the fermentation activities of the cell immobilized in thin films began to decline to a yield of 0.57 g/g at the end.


Assuntos
Resinas Acrílicas/química , Candida tropicalis/metabolismo , Técnicas de Cultura de Células/métodos , Oryza/microbiologia , Componentes Aéreos da Planta/microbiologia , Polissacarídeos/metabolismo , Xilitol/metabolismo , Células Imobilizadas , Géis/química , Hidrólise
6.
Food Chem Toxicol ; 46(1): 105-14, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17703862

RESUMO

The aim of the present study was to investigate the antioxidant activity of aqueous extracts of Toona sinensis (TS; 0-100 microg/mL) and gallic acid (0-50 microg/mL), with the purified natural phenolic components evaluated using different antioxidant models. It was found that the TS extracts and gallic acid possess effective antioxidant activity against various oxidative systems in vitro, including the scavenging of free and superoxide anion radicals, reducing power, and metal chelation. However, antioxidant activity in terms of metal chelation was not observed for the gallic acid. Moreover, TS extracts and gallic acid appear to possess powerful antioxidant properties with respect to oxidative modification of human LDL induced by CuSO4, AAPH or sodium nitroprusside, as assessed by the relative electrophoretic mobility, TBARS formation, and cholesterol degradation of oxidized LDL. Furthermore, AAPH-induced oxidative hemolysis, lipid peroxidation, and decline in superoxide dismutase (SOD) activity in human erythrocytes were prevented by both the TS extracts and the gallic acid. Our findings suggest that T. sinensis may act as a chemopreventative agent, providing antioxidant properties and offering effective protection from atherogenesis.


Assuntos
Antioxidantes/farmacologia , Meliaceae/química , Animais , Antioxidantes/química , Compostos de Bifenilo , Quelantes/química , LDL-Colesterol/química , Sulfato de Cobre/química , Ensaio de Desvio de Mobilidade Eletroforética , Eritrócitos/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Ácido Gálico/farmacologia , Hemólise/efeitos dos fármacos , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Nitroprussiato/química , Oxirredução , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Superóxidos/química , Substâncias Reativas com Ácido Tiobarbitúrico/química
7.
Food Chem Toxicol ; 45(7): 1107-15, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17391824

RESUMO

The objective of this study was to investigate the fermented culture broth of Antrodia camphorata (A. camphorata) to induce apoptosis and inhibit cyclooxygenase-2 (COX-2) in estrogen-nonresponsive (MDA-MB-231) human breast cancer cells. Treatment of the highly invasive MDA-MB-231 cells with A. camphorata (40-240 microg/ml) resulted in dose and time-dependent sequences of events marked by apoptosis, as evidenced by loss of cell viability, chromatin condensation, and internucleosomal DNA fragmentation. Apoptosis in the MDA-MB-231 cells was accompanied by release of cytochrome c, activation of caspase-3, -8, and -9, and specific proteolytic cleavage of poly (ADP-ribose) polymerase (PARP). Although the A. camphorata-induced apoptosis was associated with a reduction in Bcl-2 protein levels, negligible Bax increase was observed. Furthermore, A. camphorata treatment inhibited COX-2 protein expression and prostaglandin E2 (PGE2) production in MDA-MB-231 cells. Analysis of the study data suggests that A. camphorata exerts growth inhibition on (highly invasive) estrogen-nonresponsive human breast cancer cells through apoptosis induction associated with COX-2 inhibition, and that it may possess anticancer properties potentially valuable for application in drug products.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Polyporales/química , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estrogênios/farmacologia , Humanos
8.
J Am Soc Mass Spectrom ; 18(5): 910-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17368044

RESUMO

Iron oxide nanoparticles modified with oleate have been employed for the extraction of peptides and proteins from aqueous solution before matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) analysis. Adsorption of peptides and proteins onto the nanoparticles were mainly through electrostatic attraction and hydrophobic interaction. The analyte-adsorbed iron oxide nanoparticles could be efficiently collected from solution using a magnet. No elution step was needed. With this preconcentration strategy, the lowest detectable concentration of angiotensin I, insulin, and myoglobin in 500 microL of aqueous solution were 0.1 nM, 0.1 nM, and 10.0 nM, respectively. In addition, the nanoparticles could extract the analytes from solution with a high content of salt and surfactant, thus eliminating suppression effect during MALDI MS analysis. This method was successfully applied to concentrate the tryptic digest products of cytochrome c. In addition, the tryptic digestion of cytochrome c can be directly conducted on the iron oxide nanoparticles.


Assuntos
Compostos Férricos/química , Mapeamento de Peptídeos/métodos , Peptídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sequência de Aminoácidos , Animais , Bovinos , Dados de Sequência Molecular , Nanotecnologia/métodos , Ácido Oleico/química
9.
Cancer Lett ; 231(2): 215-27, 2006 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-16399223

RESUMO

Antrodia camphorata (A. camphorata) is well known in Taiwan as a traditional Chinese medicine, and it has been shown to exhibit antioxidant and anticancer effects. In this study, therefore, its ability to induce apoptosis in cultured MCF-7 breast cancer cells was studied. Treatment of the MCF-7 cells with a variety of concentrations of the fermented culture broth of A. camphorata (25-150 microg/ml) resulted in dose- and time-dependent sequences of events marked by apoptosis, as shown by loss of cell viability, chromatin condensation, internucleosomal DNA fragmentation, and sub-G1 phase accumulation. Furthermore, apoptosis in the MCF-7 cells was accompanied by the release of cytochrome c, activation of caspase 3, and specific proteolytic cleavage of poly (ADP-ribose) polymerase (PARP). Although, the A. camphorata-induced apoptosis was associated with Bax protein levels, negligible Bcl-2 reduction was observed. Interestingly, A. camphorata induced dose-dependent reactive oxygen species (ROS) generation in MCF-7 cells. Analysis of the data suggests that A. camphorata exerts antiproliferative action and growth inhibition on MCF-7 cells through apoptosis induction, and that it may have anticancer properties valuable for application in drug products.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fase G1/efeitos dos fármacos , Polyporales/química , Espécies Reativas de Oxigênio/metabolismo , Anexina A5/metabolismo , Neoplasias da Mama/patologia , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Relação Dose-Resposta a Droga , Feminino , Citometria de Fluxo , Humanos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas , Proteína X Associada a bcl-2/metabolismo
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