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1.
Phytochemistry ; 175: 112376, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32304910

RESUMO

Three undescribed isoflavones, derriscandenon A, B, and C, together with seven known isoflavones were isolated and structurally characterized during a study of the chemical constituents in the leaves of Derris scandens (Roxb.) Benth (Leguminosae, Fabaceae) collected in Bangladesh. The inhibitory activity of the compounds against activation of Epstein-Barr virus antigen (EBV-EA) by 12-O-tetradecanoylphorbo-13-acetate (TPA) was measured to identify possible chemopreventive agents. Mild inhibitory effects (IC50 278-290 mol ratio/32 pmol TPA) against EBV-EA induction compared with curcumin (IC50 341 mol ratio/32 pmol TPA) were observed for four known compounds (lupalbigenin, isopalbigenin, glyurallin, and isangustone A). Next, we focused on antitumor effects and investigated cell viability, cell proliferation, and mitochondria membrane potential by using an MTT assay, a live cell monitoring system, and fluorescence staining. Of the seven isoflavones tested for cell viability, a dose-dependent decrease in cell viability was observed for four isoflavones (derriscandenon B and C, derrubone, and glyurallin) in KB cells and two compounds (derriscandenon B and isochandaisone) in NALM6-MSH+ cells. In addition, the proliferation of KB cells was significantly inhibited by these four compounds at a concentration of 5 µM. The mitochondria membrane potentials of KB cells treated with derriscandenon C, derrubone, and glyurallin at the IC50 concentration were decreased by about 55%, whereas undescribed compound derriscandenon B had no effect. Our results show that some of the compounds isolated from D. scandens may be suitable as seed compounds for cancer prevention and therapy.


Assuntos
Derris , Fabaceae , Isoflavonas , Neoplasias , Bangladesh , Humanos
2.
Sci Rep ; 8(1): 12474, 2018 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127518

RESUMO

Seven cDNA clones encoding terpene synthases (TPSs), their structures closely related to each other, were isolated from the flower of Camellia hiemalis ('Kantsubaki'). Their putative TPS proteins were phylogenetically positioned in a sole clade with the TPSs of other Camellia species. The obtained Tps genes, one of which was designated ChTps1 (ChTps1a), were introduced into mevalonate-pathway-engineered Escherichia coli, which carried the genes for utilizing acetoacetate as a substrate, and cultured in a medium including lithium acetoacetate. Volatile products generated in the E. coli cells transformed with ChTps1 were purified from the cell suspension culture, and analyzed by NMR. Consequently, the predominant product with ChTPS1 was identified as valerianol, indicating that the ChTps1 gene codes for valerianol synthase. This is the first report on a gene that can mediate the synthesis of valerianol. We next synthesized a Tps ortholog encoding ChTPS1variant R477H (named CsiTPS8), whose sequence had been isolated from a tea tree (Camellia sinensis), carried out similar culture experiment with the E. coli transformant including CsiTps8, and consequently found valerianol production equally. Furthermore, GC-MS analysis of several teas revealed that valerianol had been an unknown ingredient in green tea and black tea.


Assuntos
Alquil e Aril Transferases/genética , Camellia/genética , Proteínas de Plantas/genética , Sesquiterpenos/metabolismo , Chá/genética , DNA Complementar/genética , Escherichia coli/genética , Flores/genética , Cromatografia Gasosa-Espectrometria de Massas/métodos , Regulação da Expressão Gênica de Plantas/genética , Filogenia
3.
J Ethnopharmacol ; 214: 37-46, 2018 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-29197545

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ficus hispida L.f. (Moraceae) has been used as alternative for traditional medicine in the treatment of various ailments including cancer-cure. The aim of this study was to evaluate the cancer chemopreventive and anticancer activities of crude extracts of F. hispida, with the objective to screen the inhibition of Epstein-Barr virus early antigen, and cytotoxic active components, and provide foundation for potential applications of this promising medical plant. MATERIALS AND METHODS: Compounds were isolated from the MeOH extract of F. hispida fruits, and their structure elucidation was performed on the basis of extensive spectroscopic analysis. The isolated compounds were evaluated for their inhibitory activities against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, and cytotoxic activities against human cancer cell lines (HL60, A549, SKBR3, KB, Hela, HT29, and HepG2) and a normal cell (LO2) using MTT method. For the compound with potent cytotoxic activity, its apoptosis inducing activity was evaluated by the observation of ROS generation level expression, and membrane phospholipid exposure and DNA fragmentation in flow cytometry. The mechanisms of the apoptosis induction were analyzed by Western blotting. RESULTS: Nineteen compounds, 1-19, including two new isoflavones, 3'-formyl-5,7-dihydroxy-4'-methoxyisoflavone (2) and 5,7-dihydroxy-4'-methoxy-3'- (3-methyl-2-hydroxybuten-3-yl)isoflavone (3), were isolated from the MeOH extract of F. hispida fruits. Five compounds, isowigtheone hydrate (1), 2, 3, 9, and 19, showed potent inhibitory effects on EBV-EA induction with IC50 values in the range of 271-340 molar ratio 32 pmol-1 TPA. In addition, five phenolic compounds, 1-3, 10, and 13, exhibited cytotoxic activity against two or more cell lines (IC50 2.5-95.8µM), as well as compounds 1 and 3 were also displayed high selectivity for LO2/HepG2 (SI 23.5 and 11.8, respectively), while the compound 1-induced ROS generation leads to activated caspases-3, -8, and -9 apoptotic process in HL60 cells. CONCLUSION: This study has established that the MeOH extract of F. hispida fruits contains isoflavones, coumarins, caffeoylquinic acids, along with other compounds including phenolics and steroid glucoside as active principles, and has demonstrated that the chemical constituents of F. hispida may be valuable as potential chemopreventive and anticancer agents.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Ficus , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Células A549 , Anticarcinógenos/isolamento & purificação , Antígenos Virais/metabolismo , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Relação Dose-Resposta a Droga , Ficus/química , Frutas , Células HL-60 , Células HT29 , Células HeLa , Células Hep G2 , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/metabolismo , Humanos , Concentração Inibidora 50 , Metanol/química , Neoplasias/metabolismo , Neoplasias/patologia , Fitoterapia , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Espécies Reativas de Oxigênio/metabolismo , Solventes/química
4.
Molecules ; 22(4)2017 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406454

RESUMO

Aplysiatoxin (ATX) is a protein kinase C (PKC) activator with potent tumor-promoting activity. In contrast, 10-methyl-aplog-1 (1), a simplified analog of ATX, was anti-proliferative towards several cancer cell lines without significant tumor-promoting and proinflammatory activities. To determine the effects of the phenolic group on the biological activities of 1, we synthesized new derivatives (2, 3) that lack the phenolic hydroxyl group and/or the aromatic ring. Compound 2, like 1, showed potent anti-proliferative activity against several cancer cell lines, but little with respect to tumor-promoting and proinflammatory activities. In contrast, 3 exhibited weaker growth inhibitory activity, and promoted inflammation and tumorigenesis. The binding affinity of 3 for PKCδ, which is involved in growth inhibition and apoptosis, was several times lower than those of 1 and 2, possibly due to the absence of the hydrogen bond and CH/π interaction between its side chain and either Met-239 or Pro-241 in the PKCδ-C1B domain. These results suggest that both the aromatic ring and phenolic hydroxyl group can suppress the proinflammatory and tumor-promoting activities of 1 and, therefore, at least the aromatic ring in the side chain of 1 is indispensable for developing anti-cancer leads with potent anti-proliferative activity and limited side effects. In accordance with the binding affinity, the concentration of 3 necessary to induce PKCδ-GFP translocation to the plasma membrane and perinuclear regions in HEK293 cells was higher than that of 1 and 2. However, the translocation profiles for PKCδ-GFP due to induction by 1-3 were similar.


Assuntos
Carcinógenos/química , Carcinógenos/farmacologia , Toxinas de Lyngbya/química , Toxinas de Lyngbya/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Modelos Moleculares , Estrutura Molecular , Proteína Quinase C/química , Proteína Quinase C/metabolismo , Proteína Quinase C-delta/química , Proteína Quinase C-delta/metabolismo , Relação Estrutura-Atividade
5.
Planta Med ; 83(3-04): 300-305, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27392244

RESUMO

A new chromone, 2-(2-hydroxy-2-phenylethyl)chromone (1), was isolated together with ten known phenylethyl chromones from MeOH extracts of agarwood (Aquilaria filaria). The selected compounds were evaluated in an antiproliferative assay against five human tumor cell lines, including a multidrug-resistant cell line. They were also tested for antitumor promoting activity, as mediated by 12-O-tetradecanoylphorbol-13-acetate-induced activation of the Epstein-Barr virus early antigen in Raji cells. Among all compounds, 4',7-dimethyoxy-6-hydroxychromone (2) displayed broad spectrum antiproliferative activity against all tumor cell lines tested with IC50 values of 25-38 µM, while 8 was selectively inhibitory against multidrug-resistant cells. All tested compounds suppressed tumor promotion at noncytotoxic concentrations. 4',6-Dihydroxyphenylethylchromone (7) exhibited the most potent effect with an IC50 value of 319 mol ratio relative to 12-O-tetradecanoylphorbol-13-acetate. This study is the first to report the antitumor promoting activity of 2-(2-phenylethyl)chromone derivatives, as well as the selective antiproliferative activity of 8 against a multidrug-resistant tumor cell line.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cromonas/química , Cromonas/farmacologia , Thymelaeaceae/química , Antígenos Virais/metabolismo , Antineoplásicos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Cromonas/isolamento & purificação , Resistencia a Medicamentos Antineoplásicos , Flavonoides/química , Flavonoides/farmacologia , Humanos , Concentração Inibidora 50 , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia
6.
Acta Pol Pharm ; 74(1): 137-145, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29474770

RESUMO

A series of 2-oxindole derivatives were synthesized and evaluated for cytotoxic activity against different human and murine cancer cell lines and cancer chemopreventive activity. Among the tested compounds VS-06, 08, 12 and 17 displayed cytotoxic activity in the range of 5.0 to 8.5 pM against human T-lymphocyte cells (CEM). Results showed that molecules with electron withdrawing substituent at 4 position of N-phenylacetamide group exhibited an increase in activity against the human tumor cell line CEM. The cancer chemo- preventive effect of VS-01 (IC50 = 451 nM) displayed equipotent activity in comparison to standard oleanolic acid (IC50 = 449 nM).


Assuntos
Anticarcinógenos/síntese química , Antineoplásicos/síntese química , Animais , Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Relação Estrutura-Atividade
7.
J Nat Prod ; 79(11): 2890-2897, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933896

RESUMO

Six acetophenone derivatives, acronyculatins I (1), J (2), K (3), L (4), N (5), and O (6), were recently isolated from Acronychia trifoliolata, and the structure of the known acronyculatin B (7) was revised. Because of the limited quantities of isolated products as well as their structure similarity, racemic acronyculatins I-L, N, O, and B (1-7) were synthesized to confirm their structures and to obtain sufficient material for biological evaluation. Trihydroxyacetophenone was converted to the target compounds by various sequences of hydroxy group protection, allylation or prenylation, and epoxidation followed by cyclization. C-Prenylations were carried out by direct addition of a prenyl group or through 1,3- or 3,3-sigmatropic rearrangement. The synthesized racemic compounds were evaluated in an anti-tumor-promoting assay using the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate in Raji cells. All tested compounds significantly inhibited EBV-EA activation. Especially, racemic acronyculatin I (1) displayed the most potent inhibitory effects, with an IC50 value of 7.3 µM.


Assuntos
Acetofenonas/síntese química , Acetofenonas/farmacologia , Rutaceae/química , Acetofenonas/química , Antígenos Virais/efeitos dos fármacos , Carcinógenos/farmacologia , Herpesvirus Humano 4/efeitos dos fármacos , Humanos , Estrutura Molecular , Neoplasias , Estereoisomerismo , Relação Estrutura-Atividade , Acetato de Tetradecanoilforbol/farmacologia
8.
J Nat Prod ; 79(9): 2324-31, 2016 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-27541714

RESUMO

Chemoprevention of human cancer appears to be a feasible strategy for cancer control, especially when chemopreventive intervention is involved during early stages of the carcinogenesis process. As a part of our ongoing research program into new chemopreventive agents, herein are reported the isolation, structural elucidation, and biological evaluation of 10 new (1-10) and three known (11-13) sesquiterpenes with a dihydro-ß-agarofuran skeleton from the leaves of Maytenus jelskii Zahlbr. Their stereostructures have been elucidated by means of spectroscopic analysis, including 1D and 2D NMR techniques, ECD studies, and biogenetic considerations. The isolated metabolites and eight previously reported sesquiterpenes (14-21) were screened for their antitumor-promoting activity using a short-term in vitro assay for Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Six compounds from this series (4, 5, 11, and 13-15) were found to exhibit higher efficacies than ß-carotene, used as reference inhibitor for EBV-EA activation. In particular, promising antitumor activity was observed for compound 5, exhibiting inhibition even at the lowest concentration assayed (10 mol ratio/TPA). Preliminary structure-activity relationship analysis revealed that the acetate, benzoate, and hydroxy groups are the most desirable substituents on the sesquiterpene scaffold for activity in the EBV-EA activation assay.


Assuntos
Anticarcinógenos , Maytenus/química , Sesquiterpenos , Anticarcinógenos/química , Anticarcinógenos/isolamento & purificação , Anticarcinógenos/farmacologia , Antígenos Nucleares do Vírus Epstein-Barr/efeitos dos fármacos , Antígenos Nucleares do Vírus Epstein-Barr/farmacologia , Humanos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Peru , Folhas de Planta/química , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Estereoisomerismo , Relação Estrutura-Atividade , Acetato de Tetradecanoilforbol/farmacologia
9.
Eur J Med Chem ; 111: 95-102, 2016 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-26854381

RESUMO

Inhibition of tumour promotion in multistage chemical carcinogenesis is considered a promising strategy for cancer chemoprevention. In an ongoing investigation of bioactive secondary metabolites from Celastraceae species, five new dihydro-ß-agarofuran sesquiterpenes (1-5), named Chiapens A-E, and seventeen known ones, were isolated from Maytenus chiapensis. Their structures were elucidated by extensive NMR spectroscopic and mass spectrometric techniques, and their absolute configurations were determined by circular dichroism studies, chemical correlations and biogenic means. The isolated compounds, along with twenty known sesquiterpenes, previously isolated from Zinowiewia costaricensis, have been tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorpol-13-acetate (TPA). Thirty three compounds from this series showed stronger effects than that of ß-carotene, the reference inhibitor. The structure-activity relationship (SAR) analysis revealed that the type of substituent, in particular at the C-1 position of the sesquiterpene scaffold, was able to modulate the anti-tumour promoting activity. Compounds 3, 6, and 33 showed significant effects in an in vivo two-stage mouse-skin carcinogenesis model.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Celastraceae/química , Papiloma/tratamento farmacológico , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Animais , Antígenos Virais/metabolismo , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos ICR , Modelos Moleculares , Estrutura Molecular , Papiloma/metabolismo , Papiloma/patologia , Sesquiterpenos/síntese química , Relação Estrutura-Atividade , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/antagonistas & inibidores , Acetato de Tetradecanoilforbol/farmacologia
10.
Nat Prod Commun ; 11(9): 1299-1302, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30807028

RESUMO

From the roots of Acronychia pedunculata (L.) Miq. (Rutaceae) collected in Taiwan, six known and three new acetophenones have been isolated. The new compounds were named acrophenones D (1), E (2), and F (3). Of the acetophenones isolated in this study, prenylacronylin (4) and acronyculatin D. (10) exhibited significant inhibitory activity against 12-0-tetradecanoylphorbol 13-acetate-induced Epstein-Barr virus early antigen activation in Raji cells.


Assuntos
Acetofenonas/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Rutaceae/química , Acetofenonas/isolamento & purificação , Antígenos Virais , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Raízes de Plantas/química , Taiwan
11.
Acta Pol Pharm ; 73(4): 913-929, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-29648717

RESUMO

A series of 2-(4-methylbenzyl)-5,6-substituted-imidazo[2,1-b][1,3,4]thiadiazole derivatives were synthesized, characterized and evaluated for antiproliferative activity and cancer chemopreventive activity. Results showed that molecules with formyl and thiocyanate substiments at the 5 position exhibited an increase in activity against the full panel of 60 human tumor cell lines at a minimum of five concentrations at 10-fold dilutions. Derivative 22 displayed significant in vino anticancer activity against colon cancer (MID GI50 = 0.75 µM). The cancer chemopreventive effect of 19 (IC50 = 489 nM) was almost equipotent to standard oleanolic acid (IC50 = 449 nM).


Assuntos
Anticarcinógenos/síntese química , Antineoplásicos/síntese química , Imidazóis/síntese química , Tiadiazóis/síntese química , Animais , Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Imidazóis/farmacologia , Camundongos , Camundongos Endogâmicos ICR , Tiadiazóis/farmacologia
12.
Nat Prod Res ; 30(10): 1205-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26134930

RESUMO

In this study, the anti-tumour-promoting and thermal-induced protein denaturation inhibitory activities of ß-sitosterol (1) and lupeol (2), isolated from Diospyros lotus L., were explored. Compound 1 showed a marked concentration-dependent inhibition against 12-O-tetradecanoylphorbol-13-acetate (20 ng/32 pmol)-induced Epstein-Barr virus early antigen activation in Raji cells with IC50 of 270 µg/ml, without significant toxicity (70% viability). Compound 2 showed significant anti-tumour-promoting effect with IC50 of 412 µg/ml, without significant toxicity (60% viability). In heat-induced protein denaturation assay, compound 1 exhibited a concentration-dependent attenuation with a maximum effect of 73.5% at 500 µg/ml with EC50 of 117 µg/ml, while compound 2 exhibited a maximum effect of 59.2% at 500 µg/ml with EC50 of 355 µg/ml. Moreover, in silico docking studies against the phosphoinositide 3-kinase enzyme also show the inhibitory potency of these compounds. In short, both the compounds exhibited a marked anti-tumour-promoting and potent inhibitory effect on thermal-induced protein denaturation.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Diospyros/química , Triterpenos Pentacíclicos/farmacologia , Sitosteroides/farmacologia , Animais , Antígenos Virais/metabolismo , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Triterpenos Pentacíclicos/isolamento & purificação , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Desnaturação Proteica/efeitos dos fármacos , Sitosteroides/isolamento & purificação , Acetato de Tetradecanoilforbol
13.
Biosci Biotechnol Biochem ; 80(2): 221-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26452398

RESUMO

Aplog-1 is a simplified analog of debromoaplysiatoxin (DAT) with potent tumor-promoting and proinflammatory activities. Aplog-1 and DAT exhibited anti-proliferative activities against several human cancer cell lines, whereas aplog-1 did not have tumor-promoting nor proinflammatory activities. We have recently found 10-methyl-aplog-1 (1) to have strong anti-proliferative activity compared with aplog-1. To further investigate the structural factors involved in the tumor-promoting, proinflammatory, and anti-proliferative activities, two dimethyl derivatives of aplog-1 (2, 3) were synthesized, where two methyl groups were installed at positions 4 and 10 or 10 and 12. 10,12-Dimethyl-aplog-1 (2) had stronger inhibitory effects on the growth of several human cancer cell lines than 1 and DAT, but exhibited no tumor-promoting and proinflammatory activities. In contrast, 4,10-dimethyl-aplog-1 (3) displayed weak tumor-promoting and proinflammatory activities along with anti-proliferative activity similar to that of 1 and DAT. Compound 2 would be the optimized seed for anticancer drugs among the simplified analogs of DAT.


Assuntos
Antineoplásicos/síntese química , Carcinógenos/síntese química , Lactonas/síntese química , Toxinas de Lyngbya/síntese química , Animais , Antineoplásicos/farmacologia , Carcinógenos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Lactonas/farmacologia , Toxinas de Lyngbya/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Papiloma/induzido quimicamente , Papiloma/patologia , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia , Relação Estrutura-Atividade
14.
Nutr Res ; 35(7): 618-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26077869

RESUMO

4-Hydroxyderricin (4HD) and xanthoangelol (XAG) are major components of n-hexane/ethyl acetate (5:1) extract of the yellow-colored stem juice of Angelica keiskei. 4-Hydroxyderricin and XAG have been reported to increase glucose transporter 4 (GLUT4)-dependent glucose uptake in 3T3-L1 adipocytes, but the detailed mechanism of this phenomenon remains unknown. This present study was aimed at clarifying the detailed mechanism by which 4HD and XAG increase GLUT4-dependent glucose uptake in 3T3-L1 adipocytes. Both 4HD and XAG increased glucose uptake and GLUT4 translocation to the plasma membrane. 4-Hydroxyderricin and XAG also stimulated the phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase. In addition, phosphorylation of liver kinase B1 (LKB1), which acts upstream of AMPK, was also increased by 4HD and XAG treatment. Small interfering RNA knockdown of LKB1 attenuated 4HD- and XAG-stimulated AMPK phosphorylation and suppressed glucose uptake. These findings demonstrate that 4HD and XAG can increase GLUT4-dependent glucose uptake through the LKB1/AMPK signaling pathway in 3T3-L1 adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Angelica/química , Chalconas/farmacologia , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Extratos Vegetais/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Células 3T3-L1 , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/metabolismo , Animais , Chalcona/análogos & derivados , Chalcona/farmacologia , Camundongos , Fosforilação , Caules de Planta , RNA Interferente Pequeno , Transdução de Sinais
15.
Chem Biodivers ; 12(4): 547-58, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25879500

RESUMO

Two jasmonate derivatives, glucosylcucurbic acid (1) and methyl glucosylcucurbate (2), were isolated from the MeOH extract of defatted shea (Vitellaria paradoxa; Sapotaceae) kernels. These and their deglucosylated derivatives, cucurbic acid (3) and methyl cucurbate (4), were evaluated for their melanogenesis-inhibitory and cancer chemopreventive potencies. Compounds 1, 3, and 4 exhibited potent melanogenesis-inhibitory activities in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 melanoma cells. Western-blot analysis revealed that compounds 1 and 3 reduced the protein levels of MITF (=microphthalmia-associated transcription factor), tyrosinase, TRP-1 (=tyrosine-related protein 1), and TRP-2 mostly in a concentration-dependent manner. In addition, compound 1 exhibited inhibitory effects against Epstein-Barr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, against TPA-induced inflammation in mice, and against skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter.


Assuntos
Anticarcinógenos/química , Anticarcinógenos/farmacologia , Glucosídeos/farmacologia , Melaninas/metabolismo , Oxilipinas/farmacologia , Sapotaceae/química , Animais , Antígenos Virais/metabolismo , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Glucosídeos/química , Humanos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos Endogâmicos , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Oxirredutases/metabolismo , Oxilipinas/química , Extratos Vegetais/química , Sementes/química , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Acetato de Tetradecanoilforbol/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , alfa-MSH/metabolismo , alfa-MSH/farmacologia
16.
Biosci Biotechnol Biochem ; 79(6): 888-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25612633

RESUMO

Aplog-1 is a simplified analog of the tumor-promoting aplysiatoxin with anti-proliferative and cytotoxic activities against several cancer cell lines. Our recent findings have suggested that protein kinase Cδ (PKCδ) could be one of the target proteins of aplog-1. In this study, we synthesized amide-aplog-1 (3), in which the C-1 ester group was replaced with an amide group, to improve chemical stability in vivo. Unfortunately, 3 exhibited seventy-fold weaker binding affinity to the C1B domain of PKCδ than that of aplog-1, and negligible anti-proliferative and cytotoxic activities even at 10(-4) M. A conformational analysis and density functional theory calculations indicated that the stable conformation of 3 differed from that of aplog-1. Since 27-methyl and 27-methoxy derivatives (1, 2) without the ability to bind to PKC isozymes exhibited marked anti-proliferative and cytotoxic activities at 10(-4) M, 3 may be an inactive control to identify the target proteins of aplogs.


Assuntos
Amidas/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Toxinas de Lyngbya/síntese química , Toxinas de Lyngbya/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Humanos , Isoenzimas/antagonistas & inibidores , Toxinas de Lyngbya/química , Modelos Moleculares , Conformação Molecular , Proteína Quinase C-delta/antagonistas & inibidores , Relação Estrutura-Atividade
17.
J Agric Food Chem ; 63(5): 1622-30, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25633727

RESUMO

Three new oxidative metabolites of lycopenes, (erythro)-lycopene-5,6-diol, (threo)-lycopene-5,6-diol, and 1,16-dehydro-2,6-cyclolycopene-5-ol B, and four new oxidative metabolites of γ-carotenes, 2',6'-cyclo-γ-carotene-1',5'-diol A, 2',6'-cyclo-γ-carotene-1',5'-diol B, (erythro)-γ-carotene-5,6-diol, and (threo)-γ-carotene-5,6-diol, were isolated as minor components from the aril of gac, Momordica cochinchinensis. These structures were determined on the basis of spectroscopic data, and some of them were compared to the structures of synthetic samples. Furthermore, the oxidative metabolic conversion pathways of lycopene and γ-carotene were discussed.


Assuntos
Carotenoides/química , Momordica/química , Extratos Vegetais/química , Carotenoides/metabolismo , Frutas/química , Frutas/metabolismo , Licopeno , Momordica/metabolismo , Oxirredução , Extratos Vegetais/metabolismo
18.
Nat Prod Res ; 29(18): 1775-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25588733

RESUMO

This study was designed to evaluate the isolated flavonoids (chrysin 1, and umbelliferone 2) from Potentilla evestita for cytotoxic, antitumour-promoting and inhibition of protein denaturation activities. The results showed marked cytotoxic effect of compounds 1 and 2 in brine shrimp cytotoxic assay at various concentrations with LD50 of 34.5 and 31.8 mg/mL, respectively. In Epstein-Barr-virus early antigen activation assay, both compounds 1 and 2 illustrated significant antitumour-promoting effect with IC50 values of 462 and 308 mol ratio/32 pmol TPA, respectively. The cytotoxic and antitumour-promoting effects of compounds were strongly supported by inhibition of protein denaturation activity with IC50 of 119 and 112 µg/mL, respectively. In conclusion, both compounds possess strong cytotoxic, antitumour-promoting and inhibition of protein denaturation activities.


Assuntos
Antineoplásicos Fitogênicos/química , Flavonoides/química , Extratos Vegetais/química , Potentilla/química , Desnaturação Proteica/efeitos dos fármacos , Umbeliferonas/química , Animais , Artemia , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Dose Letal Mediana , Estrutura Molecular
19.
Phytochemistry ; 108: 157-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25446237

RESUMO

The MeOH extract of defatted shea (Vitellaria paradoxa; Sapotaceae) kernels was investigated for its constituents, and fifteen oleanane-type triterpene acids and glycosides, two steroid glucosides, two pentane-2,4-diol glucosides, seven phenolic compounds, and three sugars, were isolated. The structures of five triterpene glycosides were elucidated on the basis of spectroscopic and chemical methods. Upon evaluation of the bioactivity of the isolated compounds, it was found that some or most of the compounds have potent or moderate inhibitory activities against the following: melanogenesis in B16 melanoma cells induced by α-melanocyte-stimulating hormone (α-MSH); generation of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, against Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-teradecanoylphorbol 13-acetate (TPA) in Raji cells; t TPA-induced inflammation in mice, and proliferation of one or more of HL-60, A549, AZ521, and SK-BR-3 human cancer cell lines, respectively. Western blot analysis established that paradoxoside E inhibits melanogenesis by regulation of expression of microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-1 (TRP-1) and TRP-2. In addition, tieghemelin A was demonstrated to exhibit cytotoxic activity against A549 cells (IC50 13.5 µM) mainly due to induction of apoptosis by flow cytometry. The extract of defatted shea kernels and its constituents may be, therefore, valuable as potential antioxidant, anti-inflammatory, skin-whitening, chemopreventive, and anticancer agents.


Assuntos
Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Sapotaceae/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Animais , Antígenos Virais/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Glicosídeos/química , Células HL-60 , Humanos , Melaninas/antagonistas & inibidores , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Ressonância Magnética Nuclear Biomolecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , Oxirredutases , Picratos/farmacologia , Saponinas/farmacologia , Sementes/química , Triterpenos/química , alfa-MSH/efeitos dos fármacos
20.
Chem Biodivers ; 11(8): 1121-39, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25146759

RESUMO

Nine limonoids, 1-9, one apocarotenoid, 11, one alkaloid, 12, and one steroid, 13, from the leaf extract; and one triterpenoid, 10, five steroids, 14-18, and two flavonoids, 19 and 20, from the bark extract of Melia azedarach L. (Chinaberry tree; Meliaceae) were isolated. Among these compounds, three compounds, 4-6, were new, and their structures were established as 3-deacetyl-28-oxosalannolactone, 3-deacetyl-28-oxosalanninolide, and 3-deacetyl-17-defurano-17,28-dioxosalannin, respectively, on the basis of extensive spectroscopic analyses and comparison with literature data. All of the isolated compounds were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK-BR-3) cancer cell lines. 3-Deacetyl-4'-demethyl-28-oxosalannin (3) against HL60 and AZ521 cells, and methyl kulonate (10) against HL60 cells exhibited potent cytotoxicities with IC50 values in the range of 2.8-5.8 µM. In addition, upon evaluation of compounds 1-13 against production of nitric oxide (NO) in mouse macrophage RAW 264.7 cells induced by lipopolysaccharide (LPS), seven, i.e., trichilinin B (1), 4, ohchinin (7), 23-hydroxyohchininolide (8), 21-hydroxyisoohchininolide (9), 10, and methyl indole 3-carboxylate (12), inhibited production of NO with IC50 values in the range of 4.6-87.3 µM with no, or almost no, toxicity to the cells (IC50 93.2-100 µM). Western blot analysis revealed that compound 7 reduced the expression levels of the inducible NO synthase (iNOS) and COX-2 proteins in a concentration-dependent manner. Furthermore, compounds 5, 6, 13, and 18-20 exhibited potent inhibitory effects (IC50 299-381 molar ratio/32 pmol TPA) against Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cell line.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Limoninas/farmacologia , Melia azedarach/química , Óxido Nítrico/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Inibidores de Ciclo-Oxigenase 2/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Células HL-60 , Humanos , Concentração Inibidora 50 , Limoninas/química , Limoninas/isolamento & purificação , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Casca de Planta/química , Folhas de Planta/química
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