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1.
Phytother Res ; 28(7): 1037-44, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25289403

RESUMO

Trametenolic acid B (TAB) is the main active composition of Trametes lactinea (Berk.) Pat which possesses antitumor activities. There was no report its antitumor effect through regulating P-glycoprotein (P-gp) so far, due toP-gp over expression is one of the most important mechanisms contributing to the multiple drug resistance phenotype. The present aim was to investigate the effects of TAB on P-gp in multidrug-resistant cells;Paclitaxel-resistant cell line MDA-MB-231/Taxol was established by stepwise exposure for 10 months.MDA-MB-231 cells and MDA-MB-231/Taxol cells were treated with TAB, and their growth was evaluated using MTT assays. Paclitaxel accumulation in the cells was analyzed by high performance liquid chromatogram(HPLC). The activity of P-gp was detected by intracellular accumulation of rhodamine 123 (Rho123), and the protein expression of P-gp was evaluated using western blot. Results indicated that the IC50 of MDA-MB-231/Taxol to paclitaxel (Taxol) was 33 times higher than that of nature MDA-MB-231. TAB increased the intracellular concentration of Taxol and inhibited the activity of P-gp and suppressed the expression of P-gp in MDA-MB-231/Taxol cells. Our present results showed that TAB could reverse Taxol resistance in MDA-MB-231/Taxol cells,mainly inhibiting the activity of P-gp and down-regulating the expression level of P-gp, and then enhancing the accumulation of chemotherapy agents.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Neoplasias da Mama/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Triterpenos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Linhagem Celular Tumoral , Feminino , Humanos , Concentração Inibidora 50 , Paclitaxel/farmacologia , Trametes/química
2.
Fitoterapia ; 89: 210-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23742858

RESUMO

Trametenolic acid B (TAB), the bioactive component in the Trametes lactinea (Berk.) Pat, was reported to possess cytotoxic activities and thrombin inhibiting effects. This study was performed to investigate the effects of TAB on H(+)/K(+)-ATPase and gastric cancer. The H(+)/K(+)-ATPase inhibitory activity was determined by gastric parietal cells. Compared to the normal control group, TAB (10, 20, 40 and 80 µg/mL) inhibited the H(+)/K(+)-ATPase activity by 15.97, 16.96, 24.86 and 16.25%, respectively. In the study, 36 Kunming mice were randomly divided into six groups: control, model, TAB-L (TAB, 5 mg/kg/day, i.g.), TAB-M (TAB, 20 mg/kg/day, i.g.), TAB-H (TAB, 40 mg/kg/day, i.g.) and omeprazole (OL, 10 mg/kg/day, i.g.). All mice except the control group were administrated with anhydrous alcohol (5.0 mL/kg, i.g.) for induced gastric-ulcer 1h after the 5th day. At the same time, the control mice were given the same volume of physiological saline. After 4h, TAB was evaluated for H(+)/K(+)-ATPase inhibitory activities of ulcerative gaster, gastric ulcer index and ulcer inhibition. In vitro, the anti-proliferation effect of TAB to gastric cancer cell (HGC-27) in acid environment was detected by MTT, and the apoptosis morphological changes were also observed by Hoechst 33258 dye assay. The results indicated that TAB inhibited moderately H(+)/K(+)-ATPase activity in vitro. Compared to the model group, TAB showed anti-ulcer effects in gastric tissue with the dosages of 20 and 5 mg/kg in vivo. Apart from that, TAB could selectively inhibit gastric cancer cell viability and reduce cell apoptosis against HGC-27 cells at low doses in acid environment.


Assuntos
ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Fitoterapia , Neoplasias Gástricas/tratamento farmacológico , Úlcera Gástrica/tratamento farmacológico , Estômago/efeitos dos fármacos , Trametes/química , Triterpenos/uso terapêutico , Animais , Antiulcerosos/química , Antiulcerosos/isolamento & purificação , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ácido Gástrico/metabolismo , Camundongos , Camundongos Endogâmicos , Omeprazol/farmacologia , Células Parietais Gástricas/efeitos dos fármacos , Células Parietais Gástricas/enzimologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Inibidores da Bomba de Prótons/química , Inibidores da Bomba de Prótons/isolamento & purificação , Inibidores da Bomba de Prótons/farmacologia , Inibidores da Bomba de Prótons/uso terapêutico , Distribuição Aleatória , Estômago/enzimologia , Neoplasias Gástricas/enzimologia , Úlcera Gástrica/enzimologia , Triterpenos/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia
3.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o2949, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125734

RESUMO

In the title compound, C(15)H(24)O(4), the six-membered ring shows a distorted chair conformation and the five-membered ring adopts an envelope conformation with the C atom bearing the methyl and OH groups as the flap. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into chains running along the a-axis direction.

4.
Biol Pharm Bull ; 35(7): 1118-25, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22791160

RESUMO

The present study was to study the hepatoprotective effects of phloridzin (PHL) on hepatic fibrosis induced by carbon tetrachloride (CCl4) in rats, on the basis of this investigation, the possible mechanism of PHL was elucidated. Male Sprague Dawley (SD) rats were randomly divided into six groups: control, model, PHL-L, PHL-M, PHL-H and colchine. All rats except control group were intraperitoneally injected with CCl4, and control rats were injected with olive oil, twice a week for eight weeks. At the same time, the rats were orally given homologue drugs once a day, respectively. Hepatoprotective effects of PHL were evaluated by liver weight indexes, biochemical values, total antioxidant capacity and total-superoxide dismutase, histopathological observations, hepatic fibrosis, and the hepatic fibrosis relative gene and protein expressions. PHL significantly improved hepatic function; remarkably decreased serum hyaluronic acid (HA), transforming growth factor-ß1 (TGF-ß1), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and liver tissues hydroxyproline, malondialdehyde (MDA) levels, increased glutathione peroxidase (GSH-Px), total-antioxygen capacity (T-AOC) and total-superoxide dismutase (T-SOD) contents of liver tissues; Real-time polymerase chain reaction (PCR) and immunohisto-chemical results showed PHL might markedly reverse the up-regulated mRNA and protein expressions of the α-smooth muscle actin (SMA), TGF-ß1 and tissue inhibitor of metalloproteinase-1 (TIMP1), up-regulate the matrix metalloproteinase-1 (MMP1) mRNA and protein expressions. Histopathological observations provided supportive evidence for biochemical analyses and the hepatic fibrosis relative gene and protein expressions, and with the dose of PHL increasing, the aforesaid improvement became more and more strong. The studies demonstrated that PHL exerted beneficially hepatoprotective effects on hepatic fibrosis induced by CCl4, mainly enhancing antioxidant capacity of liver organizations, reduce the level of lipid peroxidation induced by CCl4, and protect hepatocyte membranes from damage, and alleviate hepatic fibrosis.


Assuntos
Cirrose Hepática/tratamento farmacológico , Malus , Florizina/uso terapêutico , Fitoterapia , Substâncias Protetoras/uso terapêutico , Actinas/genética , Actinas/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Tetracloreto de Carbono , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Florizina/farmacologia , Folhas de Planta , Substâncias Protetoras/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/sangue , Fator de Crescimento Transformador beta1/genética
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