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1.
Sci Rep ; 12(1): 13834, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35974087

RESUMO

The discovery of novel chemotherapeutics that act through different mechanisms is critical for dealing with tumor heterogeneity and therapeutic resistance. We previously reported a saponin analog (AG-08) that induces non-canonical necrotic cell death and is auspicious for cancer therapy. Here, we describe that the key element in triggering this unique cell death mechanism of AG-08 is its ability to form supramolecular particles. These self-assembled particles are internalized via a different endocytosis pathway than those previously described. Microarray analysis suggested that AG-08 supramolecular structures affect several cell signaling pathways, including unfolded protein response, immune response, and oxidative stress. Finally, through investigation of its 18 analogs, we further determined the structural features required for the formation of particulate structures and the stimulation of the unprecedented cell death mechanism of AG-08. The unique results of AG-08 indicated that supramolecular assemblies of small molecules are promising for the field of anticancer drug development, although they have widely been accepted as nuisance in drug discovery studies.


Assuntos
Neoplasias , Sapogeninas , Morte Celular , Humanos , Neoplasias/patologia , Resposta a Proteínas não Dobradas
2.
Phytochemistry ; 195: 113038, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34902703

RESUMO

Polyether ionophores represent a large group of naturally occurring compounds mainly produced by Streptomyces species. With previously proven varieties of bioactivity including antibacterial, antifungal, antiparasitic, antiviral and anti-tumor effects, the discovery of undescribed polyethers leading to development of efficient therapeutics has become important. As part of our research on polyether-rich Streptomyces cacaoi, we previously performed modification studies on fermentation conditions to induce synthesis of specialized metabolites. Here, we report four undescribed and nine known polyether compounds from S. cacaoi grown in optimized conditions. Antimicrobial activity assays revealed that four compounds, including the undescribed (6), showed strong inhibitory effects over both Bacillus subtilis and methicillin-resistant Staphylococcus aureus (MRSA) growth. Additionally, K41-A and its C15-demethoxy derivative exhibited significant cytotoxicity. These results signified that selectivity of C15-demethoxy K41-A towards cancer cells was higher than K41-A, which prompted us to conduct mechanistic experiments. These studies showed that this uninvestigated compound acts as a multitarget compound by inhibiting autophagic flux, inducing reactive oxygen species formation, abolishing proteasome activity, and stimulating ER stress. Consequently, the optimized fermentation conditions of S. cacaoi led to the isolation of undescribed and known polyethers displaying promising activities.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Streptomyces , Antibacterianos/farmacologia , Ionóforos , Testes de Sensibilidade Microbiana
3.
Molecules ; 26(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069653

RESUMO

Microbial biotransformation is an important tool in drug discovery and for metabolism studies. To expand our bioactive natural product library via modification and to identify possible mammalian metabolites, a cytotoxic cardenolide (gitoxigenin) was biotransformed using the endophytic fungus Alternaria eureka 1E1BL1. Initially, oleandrin was isolated from the dried leaves of Nerium oleander L. and subjected to an acid-catalysed hydrolysis to obtain the substrate gitoxigenin (yield; ~25%). After 21 days of incubation, five new cardenolides 1, 3, 4, 6, and 8 and three previously- identified compounds 2, 5 and 7 were isolated using chromatographic methods. Structural elucidations were accomplished through 1D/2D NMR, HR-ESI-MS and FT-IR analysis. A. eureka catalyzed oxygenation, oxidation, epimerization and dimethyl acetal formation reactions on the substrate. Cytotoxicity of the metabolites were evaluated using MTT cell viability method, whereas doxorubicin and oleandrin were used as positive controls. Biotransformation products displayed less cytotoxicity than the substrate. The new metabolite 8 exhibited the highest activity with IC50 values of 8.25, 1.95 and 3.4 µM against A549, PANC-1 and MIA PaCa-2 cells, respectively, without causing toxicity on healthy cell lines (MRC-5 and HEK-293) up to concentration of 10 µM. Our results suggest that A. eureka is an effective biocatalyst for modifying cardenolide-type secondary metabolites.


Assuntos
Alternaria/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Cardenolídeos/isolamento & purificação , Biotransformação , Cardenolídeos/farmacocinética , Cardenolídeos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Análise Espectral/métodos
4.
Chem Res Toxicol ; 33(11): 2880-2891, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33136369

RESUMO

Small molecules which activate distinct cell death pathways have promising high potential for anticancer drug research. Especially, regulated necrosis draws attention as an alternative cell death mechanism to overcome the drug resistance. Here, we report that a new semisynthetic saponin analogue (AG-08) triggers necrotic cell death with unprecedented pathways. AG-08-mediated necrosis depends on enhanced global proteolysis involving calpains, cathepsins, and caspases. Moreover, AG-08 generates several alterations in lysosomal function and physiology including membrane permeabilization, redistribution toward the perinuclear area, and lastly excessive tubulation. As a consequence of lysosomal impairment, the autophagic process was abolished via AG-08 treatment. Collectively, in addition to its ability to induce necrotic cell death, which makes AG-08 a promising candidate to cope with drug resistance, its unique activity mechanisms including autophagy/lysosome impairment and enhancement of proteolysis leading a strong death capacity emphasizes its potential for anticancer drug research.


Assuntos
Necrose/tratamento farmacológico , Proteólise , Saponinas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , Humanos , Camundongos , Conformação Molecular , Necrose/patologia , Saponinas/química
5.
Chem Biol Interact ; 307: 167-178, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31059704

RESUMO

Polyether compounds, a large group of biologically active metabolites produced by Streptomyces species have been reported to show a variety of bioactivity such as antibacterial, antifungal, antiparasitic, antiviral, and tumour cell cytotoxicity. Since some of these compounds target cancer stem cells and multi-drug resistant cancer cells, this family of compounds have become of high interest. In this study, three polyether-type metabolites (1-3), one of which was a new natural product (3), were isolated from the marine derived Streptomyces cacaoi via antimicrobial activity-guided fractionation studies. As several polyether compounds with structural similarity such as monensin have been linked with autophagy and cell death, we first assessed the cytotoxicity of these three compounds. Compounds 2 and 3, but not 1, were found to be cytotoxic in several cell lines with a higher potency towards cancer cells. Furthermore, 2 and 3 caused accumulation of both autophagy flux markers LC3-II and p62 along with cleavage of caspase-3, caspase-9 and poly (ADP-ribose) polymerase 1 (PARP-1). Interestingly, prolonged treatment of the compounds caused a dramatic downregulation of the proteins related to autophagasome formation in a dose dependent manner. Our findings provide insights on the molecular mechanisms of the polyether-type polyketides, and signify their potency as chemotherapeutic agents through inhibiting autophagy and inducing apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Produtos Biológicos/farmacologia , Streptomyces/química , Produtos Biológicos/isolamento & purificação , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Humanos , Conformação Molecular , Poli(ADP-Ribose) Polimerases/metabolismo , Streptomyces/metabolismo
6.
Steroids ; 135: 9-20, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29678446

RESUMO

Chronic inflammation is associated to 25% of cancer cases according to epidemiological data. Therefore, inhibition of inflammation-induced carcinogenesis can be an efficient therapeutic approach for cancer chemoprevention in drug development studies. It is also determined that anti-inflammatory drugs reduce cancer incidence. Cell culture-based in vitro screening methods are used as a fast and efficient method to investigate the biological activities of the biomolecules. In addition, saponins are molecules that are isolated from natural sources and are known to have potential for tumor inhibition. Studies on the preparation of analogues of cycloartane-type sapogenols (9,19-cyclolanostanes) have so far been limited. Therefore we have decided to direct our efforts toward the exploration of new anti-tumor agents prepared from cycloastragenol and its production artifact astragenol. The semi-synthetic derivatives were prepared mainly by oxidation, condensation, alkylation, acylation, and elimination reactions. After preliminary studies, five sapogenol analogues, two of which were new compounds (2 and 3), were selected and screened for their inhibitory activity on cell viability and NFκB signaling pathway activity in LNCaP prostate cancer cells. We found that the astragenol derivatives 1 and 2 as well as cycloastragenol derivatives 3, 4, and 5 exhibited strong inhibitory activity on NFκB signaling leading the repression of NFκB transcriptional activation and suppressed cell proliferation. The results suggested that these molecules might have significant potential for chemoprevention of prostate carcinogenesis induced by inflammatory NFκB signaling pathway.


Assuntos
Carcinogênese/efeitos dos fármacos , NF-kappa B/metabolismo , Neoplasias da Próstata/patologia , Sapogeninas/química , Sapogeninas/farmacologia , Triterpenos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Dinoprostona/metabolismo , Humanos , Inflamação/patologia , Masculino , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos
7.
Chem Res Toxicol ; 29(3): 415-20, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-26894873

RESUMO

Two metabolites from the ascomycete fungus Septofusidium berolinense were recently identified as having antineoplastic activity [Ekiz et al. (2015) J. Antibiot. , DOI: 10.1038/ja.2015.84]. However, the basis for this activity is not known. One of the compounds [3,6-dihydroxy-2-propylbenzaldehyde (GE-1)] is a hydroquinone, and the other [2-hydroxymethyl-3-propylcyclohexa-2,5-diene-1,4-dione (GE-2)] is a quinone. Because some hydroquinones and quinones act as topoisomerase II poisons, the effects of GE-1 and GE-2 on DNA cleavage mediated by human topoisomerase IIα were assessed. GE-2 enhanced DNA cleavage ∼4-fold and induced scission with a site specificity similar to that of the anticancer drug etoposide. Similar to other quinone-based topoisomerase II poisons, GE-2 displayed several hallmark characteristics of covalent topoisomerase II poisons, including (1) the inability to poison a topoisomerase IIα construct that lacks the N-terminal domain, (2) the inhibition of DNA cleavage when the compound was incubated with the enzyme prior to the addition of plasmid, and (3) the loss of poisoning activity in the presence of a reducing agent. In contrast to GE-2, GE-1 did not enhance DNA cleavage mediated by topoisomerase IIα except at very high concentrations. However, the activity and potency of the metabolite were dramatically enhanced under oxidizing conditions. These results suggest that topoisomerase IIα may play a role in mediating the cytotoxic effects of these fungal metabolites.


Assuntos
Antígenos de Neoplasias/metabolismo , Benzaldeídos/farmacologia , Cicloexanonas/farmacologia , Clivagem do DNA , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fungos/química , Fungos/metabolismo , Metabolismo Secundário , Benzaldeídos/química , Benzaldeídos/metabolismo , Cicloexanonas/química , Cicloexanonas/metabolismo , Humanos , Estrutura Molecular
9.
Nat Prod Commun ; 11(10): 1421-1424, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30549590

RESUMO

Leaves of Juglans regia L. collected from two different locations [Adana (A) and Ankara (B)] from Turkey were subjected to hydrodistillation in a Clevenger type apparatus to yield the essential oils (EOs). GC/MS and GC-FID analyses revealed that the A EO was rich in thymol (23.1%), while caryophyllene oxide (33.8%) was found as the main constituent of B EO. Both contained P-eudesmol (1.4% - 9.5 %), (E)-geranyl acetone (3.7% - 5.8%) and the eudesmane type constituent juglaterpene A (3.1% - 11.0%). Using a HP Innowax preparative capillary column connected to a preparative fraction collector, an unknown constituent, juglaterpene A (1, 1 l-hydroxy-2,4-cycloeudesmane), was isolated in a rapid one-step manner with > 94.0% purity. Structure determination was accomplished from ID- and 2D-NMR spectroscopic data. Oil B demonstrated significant larvicidal activity against 1st instar Aedes aegypti L.


Assuntos
Inseticidas/química , Juglans/química , Folhas de Planta/química , Óleos de Plantas/química , Sesquiterpenos/química , Aedes , Animais , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Sesquiterpenos/farmacologia
10.
Nat Prod Commun ; 11(12): 1847-1850, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30508348

RESUMO

Eight known secondary metabolites were isolated from the methanolic extract of the whole plant of Astragalus lycius Boiss. They were identified as 5,5'-dihydoxy-3'-methoxy-isoflavone-7-0-ß-D-glucoside (1), genistin (2), sissotrin (3), 5,4'-dimethoxy-isoflavone-7-0-ß-D-glucopyranoside (4), (7S,8R)-5-methoxydehydrodiconiferyl alcohol-4-0-ß-D-glucopyranoside (5), 4-0-lariciresinol-glucoside (6), 2-phenylethyl-ß-D-glucopyranoside (7) and ß-sitosterol-3-O-ß-D-glucopyranoside (8) by spectroscopic methods including (1)H- and (13)C-NMR and HR-MS experiments, and by comparison with literature values. Compounds 1-7 are reported for the first time from Astragalus taxa. All of the compounds were tested for their cytotoxic activities against a number of cancer cell lines. Among them, only 6 exhibited significant activity against human colon carcinoma (HT-29) at 2.69 µM concentration.


Assuntos
Antineoplásicos , Astrágalo/metabolismo , Compostos Fitoquímicos , Antineoplásicos/análise , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Metabolismo Secundário
11.
Phytochemistry ; 86: 184-94, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23107778

RESUMO

As a part of our ongoing research for bioactive compounds from Turkish Astragalus species, the investigation of Astragalus tauricolus has been carried out. An approach based on HPLC-ESIMS(n) experiments has been used to profile the triterpene glycosides occurring in the butanol extract of the whole plant. On the basis of the results of the online screening by HPLC-ESIMS(n), 22 oleanane-type triterpene glycosides, including ten compounds never reported before, were isolated, and their structures were established by the extensive use of 1D and 2D-NMR experiments along with ESIMS and HRMS analysis. Noteworthy, cycloartane-type triterpene glycosides, the main constituents of Astragalus spp., were not found. This peculiar feature characterizes a very limited group of Astragalus spp. The antiproliferative activity of the isolated compounds 1-12, 15, 17-19 was evaluated against a small panel of cancer cell lines. Only compound 11 showed an IC(50) of 22 µM against human leukemia cell line (U937). The other tested compounds, in a range of concentrations between 1 and 50 µM, did not cause any significant reduction of the cell number.


Assuntos
Astrágalo/química , Glicosídeos/química , Ácido Oleanólico/análogos & derivados , Cromatografia Líquida de Alta Pressão , Estrutura Molecular , Ácido Oleanólico/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
12.
J Ethnopharmacol ; 139(2): 574-81, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22155389

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus roots are used to treat leukemia and for their wound healing properties in Southeast Anatolia-Turkey. MATERIALS AND METHODS: In vivo studies to investigate the effects of two Astragalus saponins were carried out on the immune response cytokines by using six to eight weeks old male Swiss albino mice. The production of IL-1ß, TGF-1ß, TNF-α, IL-2, IL-4 and IFN-γ cytokines was determined by ELISA. The spleen and lymph nodes, isolated from the mice subjects, were analyzed to realize induction of the surface antigen productions for IL-2Rα (CD25) and CD69. In addition, their effects on the targets of inflammation such as NF κB, iNOS and NAG-1 were investigated in cell-based assays. RESULTS: The results suggested that AST VII and Mac B had positive effect on Th1 cytokine release (IL-2 and IFN-γ), and suppression on Th2 cytokine production (IL-4). The immunohistochemical results exhibited induction of both IL-Rα (CD25) and CD69 surface receptors justifying the Th1 cytokine release. The compounds did not affect NF-κB or NAG-1 activity but iNOS activity was inhibited by Mac B with an IC(50) of 156 µg/ml. CONCLUSIONS: The results show that Ast VII and Mac B create powerful immunoregulatory effects without the stimulation of inflammatory cytokines in mice, and have no significant effect on the inflammatory cellular targets in vitro.


Assuntos
Anti-Inflamatórios/farmacologia , Astrágalo , Sistema Imunitário/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Astrágalo/química , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Fator 15 de Diferenciação de Crescimento/genética , Fator 15 de Diferenciação de Crescimento/metabolismo , Células HT29 , Humanos , Sistema Imunitário/imunologia , Imuno-Histoquímica , Fatores Imunológicos/isolamento & purificação , Mediadores da Inflamação/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Lectinas Tipo C/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Saponinas/isolamento & purificação , Baço/efeitos dos fármacos , Baço/imunologia , Transfecção , Triterpenos/isolamento & purificação
13.
Biochem Biophys Res Commun ; 409(4): 738-44, 2011 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21624350

RESUMO

Endemic Alkanna cappadocica was used to isolate novel antitumor molecules from Turkish landscapes in our previous studies. In this study, deoxyalkannin (ALCAP1), ß,ß-dimethylacrylalkannin (ALCAP2), acetylalkannin (ALCAP3), and alkannin (ALCAP4) as well as the novel isolated compounds 5-methoxydeoxyalkannin (ALCAP5), 8-methoxydeoxyalkannin (ALCAP6), 5-methoxyacetylalkannin (ALCAP7), 5-methoxy-ß,ß-dimethylacrylalkannin (ALCAP8) were characterized. The topoisomerase I (topo I) inhibitory activity of ALCAPs was investigated using in vitro plasmid relaxation assay and found that ALCAP2, 3, 4 and 7 were potent inhibitors at 2-6µM concentrations. Further, DNA damage response to ALCAP treatments was also studied by measuring the H2AX((S139)) and ATM((S1981)) phosphorylations. ALCAP2, 7 and 8 induced the DNA damage and apoptosis, consistently resulted in PARP cleavage at nanomolar concentrations in K562 leukemia cells. Moreover, when the free radical (ROS) generating capacity of the compounds was studied by 2',7'-dichlorofluorescein-diacetate assay using flow cytometry, we found that a known antioxidant N-acetyl-cysteine almost completely abrogated the H2AX((S139)) phosphorylations and the caspase 3 cleavage and activation. Thus, γH2AX((S139)) foci formation remained higher than the control, and an increase in CHK2((T68)) phosphorylation was observed by ALCAP2 and 7 treatments suggested that, these compounds can be potential therapeutics against tumor cell growth because of their unique DNA damaging abilities additional to enzyme inhibition similar to those of doxorubicin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose , Boraginaceae/química , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/farmacologia , Inibidores da Topoisomerase I/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , DNA Topoisomerases Tipo I/metabolismo , Histonas/metabolismo , Humanos , Naftoquinonas/química , Naftoquinonas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/isolamento & purificação
14.
Pharm Biol ; 49(8): 840-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21612369

RESUMO

CONTEXT: Centaurea L. (Astreaceae) species are used as herbal remedies in Turkey. Centaurea calolepis Boiss. is an endemic species of Anatolia that has not been subjected to phytochemical studies except essential oil analysis. OBJECTIVE: Secondary metabolite determination, isolation and structure elucidation of pure compounds were performed on C. calolepis. Cnicin, which is the main component of several Centaurea species, was tested for its in vitro anti-inflammatory, antioxidant and cytotoxic activities. MATERIALS AND METHODS: Chloroform and methanol extracts of the aerial parts of C. calolepis were subjected to isolation process using column chromatography. The structures of the compounds were characterized by 1D- and 2D-NMR experiments. Thin-layer chromatography and high performance liquid chromatography were used in determination of phenolics. Cnicin was subjected to a panel of cellular assays to test for inhibition of nuclear factor κB (NF-κB), inducible nitric oxide synthase (iNOS), reactive oxygen species and cytotoxicity. RESULTS: Cnicin, lucenin-2, schaftoside and 3-O-feruloylquinic acid were isolated from C. calolepis extracts. Vicenin-2, vitexin, isovitexin, homoorientin, rutin, orientin, luteolin-7-O-glycoside and chlorogenic acid were determined in fractions. Cnicin showed inhibition of NF-κB and inhibition of iNOS activity with IC50 Values of 1.8 and 6.5 µM, respectively. Cytotoxic activity of cnicin was observed toward pig kidney epithelial (LLC-PK11), human malignant melanoma (SK-MEL) and human ductal carcinoma (BT-549) cells with IC50 values of 23.3, 14.0 and 18.3 µM, respectively. DISCUSSION AND CONCLUSION: This is the first detailed report of secondary metabolites of C. calolepis. Evaluation of biological activity of cnicin establishes the potential of this compound as an anti-inflammatory and cytotoxic agent.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Centaurea/metabolismo , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Centaurea/química , Citotoxinas/química , Citotoxinas/metabolismo , Citotoxinas/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Haplorrinos , Humanos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/química , Sesquiterpenos/metabolismo , Suínos , Turquia
15.
Phytochemistry ; 72(8): 761-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21377702

RESUMO

Eight cycloartane-type triterpene glycosides (1-8) were isolated from Astragalus aureus Willd along with ten known cycloartane-type glycosides (9-18). Their structures were established by the extensive use of 1D and 2D-NMR experiments along with ESIMS and HRMS analyses. Compounds 1-5 are cyclocanthogenin glycosides, whereas compounds 6-8 are based on cyclocephalogenin as aglycon, more unusual in the plant kingdom, so far reported only from Astragalus spp. Moreover, for the first time monoglycosides of cyclocanthogenin (5) and cyclocephalogenin (7, 8) are reported. All of the compounds tested for their cytotoxic activities against a number of cancer cell lines. Among the compounds, only 8 exhibited activity versus human breast cancer (MCF7) at 45 µM concentration.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Astrágalo/química , Glicosídeos/isolamento & purificação , Triterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Glicosídeos/química , Glicosídeos/farmacologia , Células HL-60 , Humanos , Masculino , Estrutura Molecular , Triterpenos/química , Triterpenos/farmacologia , Turquia
16.
Carbohydr Res ; 345(17): 2529-33, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-20937505

RESUMO

A new flavanone glycoside, naringenin-7-O-ß-D-glucuronopyranoside, and a new flavonol glycoside, 6-hydroxykaempferol-7-O-ß-D-glucuronopyranoside were isolated together with 12 known compounds, 5 flavone glycoside; hispidulin-7-O-ß-D-glucuronopyranoside, apigenin-7-O-ß-D-methylglucuronopyranoside, hispidulin-7-O-ß-D-methylglucuronopyranoside, hispidulin-7-O-ß-D-glucopyranoside, apigenin-7-O-ß-D-glucopyranoside, a flavonol; kaempferol, two flavone; apigenin, and luteolin, a flavanone glycoside; eriodictyol-7-O-ß-D-glucuronopyranoside, and three phenol glycoside; arbutin, salidroside, and 3,5-dihydroxyphenethyl alcohol-3-O-ß-D-glucopyranoside from Centaurea urvillei subsp. urvillei. The structure elucidation of the new compounds was achieved by a combination of one- ((1)H and (13)C) and two-dimensional NMR techniques (G-COSY, G-HMQC, and G-HMBC) and LC-ESI-MS. The isolated compounds were tested for their antiproteasomal activity. The results indicated that kaempferol, a well known and widely distributed flavonoid in the plant kingdom, was the most active antiproteasomal agent, followed by apigenin, eriodictyol-7-O-ß-D-glucuronopyranoside, 3,5-dihydroxyphenethyl alcohol-3-O-ß-D-glucopyranoside, and salidroside, respectively.


Assuntos
Centaurea/química , Glicosídeos/química , Glicosídeos/farmacologia , Fenóis/química , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Inibidores de Proteassoma , Linhagem Celular Tumoral , Glicosídeos/isolamento & purificação , Humanos , Inibidores de Proteases/isolamento & purificação
17.
Plant Foods Hum Nutr ; 65(2): 158-63, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20449663

RESUMO

The leaves of Rosmarinus officinalis harvested from three different locations of Turkey were extracted by both methanolic and supercritical CO(2) extraction. Subsequently, six extracts and the active compounds, carnosic acid, and rosmarinic acid were applied to various human cancer cell lines including NCI-H82 (human, small cell lung, carcinoma), DU-145 (human, prostate, carcinoma), Hep-3B (human, black, liver, carcinoma, hepatocellular), K-562 (human chronic myeloid leukemia), MCF-7 (human, breast, adenocarcinoma), PC-3 (human, prostate, adenocarcinoma) and MDA-MB-231 (human, breast, adenocarcinoma) by MTT assay. Supercritical CO(2) extracts had superior antiproliferative effect compared to the soxhlet extracts. Although the extracts exhibited various cytotoxic effects against different cell lines, comparatively low IC(50) values ranging between 12.50 and 47.55 microg/ml were attained against K-562, being the most sensitive cell line. Moreover, carnosic acid caused the lowest cell viability with values ranging from 13 to 30 % at a concentration of 19 muM after 48 h of treatments, resulting in superior antiproliferative effect. Rosemary extract is a potential candidate to be included in the anti-cancer diet with pre-determined doses avoiding toxicity.


Assuntos
Abietanos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cinamatos/uso terapêutico , Depsídeos/uso terapêutico , Neoplasias/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Rosmarinus/química , Abietanos/isolamento & purificação , Abietanos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cinamatos/isolamento & purificação , Cinamatos/farmacologia , Depsídeos/isolamento & purificação , Depsídeos/farmacologia , Humanos , Concentração Inibidora 50 , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Turquia , Ácido Rosmarínico
18.
J Nat Prod ; 73(5): 860-4, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20405844

RESUMO

In a continuing program to discover new anticancer agents from plants, especially naphthoquinones from the Alkanna genus, Alkanna cappadocica was investigated. Bioassay-guided fractionation of a dichloromethane/methanol (1:1) extract of the roots led to the isolation of four new and four known naphthoquinones. The known compounds are 11-deoxyalkannin (1), beta,beta-dimethylacrylalkannin (2), 11-O-acetylalkannin (3), and alkannin (4). The new compounds 5-O-methyl-11-deoxyalkannin (5), 8-O-methyl-11-deoxyalkannin (6), 5-O-methyl-11-O-acetylalkannin (7), and 5-O-methyl-beta,beta-dimethylacrylalkannin (8) were characterized by spectroscopic analyses (LC-ESIMS, 1D and 2D NMR). Cytotoxicity of the isolated compounds was evaluated versus 12 human cancer cell lines, HT-29, MDA-MB-231, PC-3, AU565, Hep G2, LNCaP, MCF7, HeLa, SK-BR-3, DU 145, Saos-2, and Hep 3B together with two normal cell lines, VERO and 3T3, by using the MTT assay. Compound 7 showed remarkable cytotoxicity with IC(50) values between 0.09 and 14.07 muM. It was more potent than the other compounds in six out of 12 cancer cell lines and the positive controls doxorubicin and etoposide. The mono-O-methylated alkannin derivatives and their cytotoxicities are reported for the first time.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Boraginaceae/química , Naftoquinonas/isolamento & purificação , Naftoquinonas/farmacologia , Plantas Medicinais/química , Animais , Antineoplásicos Fitogênicos/química , Chlorocebus aethiops , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Naftoquinonas/química , Turquia , Células Vero
19.
Nat Prod Commun ; 5(2): 249-52, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20334137

RESUMO

One hundred and twenty-six mesophilic Actinomycete cultures were isolated from the Aegean region of Turkey. The antimicrobial activities of pure isolates were tested using the agar-plaque method. Based on high antimicrobial activity against methicillin resistant Staphylococcus aureus (MRSA) and Escherichia coli O157-H7 (E. coli), the isolate M-33-5 was selected for bioactivity-guided isolation. Fermentation, followed by solvent partition (H2O-EtOAc, H2O-n-BuOH), showed that the highest activity was present in the EtOAc extract. By using chromatographic methods, two bioactive compounds were isolated and their structures were determined by spectral methods to be 4'-deacetyl griseusin A and griseusin A. The MIC values of griseusin A and 4'-deacetyl griseusin A against MRSA and E. coli were < or = 1.0 microg/mL. The cytotoxicities of the EtOAc extract and 4'-deacetyl griseusin A were also evaluated against two cancer cell lines (human servical cancer: HeLa; murine fibroblastic cells: L-929). The EtOAc extract showed strong cytotoxic activity against HeLa and L-929 lines with IC50 values of 1.57 and 2.43 microg/mL, respectively, whereas 4'-deacetyl griseusin A was very potent with IC50 values of 0.43 versus HeLa, and 0.12 microg/mL against L-929. The active strain M-33-5 was identified as Streptomyces griseus by 16SrDNA sequence data.


Assuntos
Actinobacteria/química , Antibacterianos/química , Antineoplásicos/química , Actinobacteria/metabolismo , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Estrutura Molecular
20.
J Chromatogr A ; 1117(2): 194-205, 2006 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-16616174

RESUMO

Essential oils from 15 Pimpinella species were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. One species, Pimpinella anisum, in which only fruits were evaluated, was also included in the study. A total of 140 different compounds were identified and significant qualitative and quantitative differences were observed among the samples. Pimpinella essential oils were characterized as having mono-, sesqui- and trinorsesquiterpenoids, propenylphenols, and pseudoisoeugenols. Trinorsesquiterpenoids and phenylpropanoids appear to be chemical markers of Pimpinella species analyzed thus far. Essential oils obtained from Pimpinella roots share the same principal compound, epoxypseudoisoeugenyl-2-methylbutyrate at concentrations from 20 to 82.6%.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/análise , Pimpinella/química , Especificidade da Espécie , Turquia
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