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1.
Drug Chem Toxicol ; 37(1): 76-82, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23829167

RESUMO

An aqueous extract of Limoniastrum guyonianum gall (G extract) was tested on Salmonella typhimurium to assess its mutagenic and antimutagenic effects. This extract showed no mutagenicity when tested with S. typhimurium strain TA104 either with or without exogenous metabolic activation mixture (S9), whereas our findings revealed that the aqueous gall extract induced a mutagenic effect in S. typhimurium TA1538 when tested in the presence, as well as in the absence, of S9 activation mixture at the concentration of 500 µg/mL. Thus, the same concentration produced a mutagenic effect, when incubated with S. typhimurium TA100 in the presence of metabolic activation mixture. In contrast, our results showed a weak antimutagenic potential of the same extract against sodium azide in the presence of S. typhimurium TA100 and S. typhimurium TA1538 without metabolic activation (S9), whereas, in the presence of S. typhimurium TA104, we obtained a significant inhibition percentage (76.39%) toward 3.25 µg/plate of methylmethanesulfonate. Antimutagenicity against aflatoxin B1, 4-nitro-o-phenylene-diamine and 2-aminoanthracène was significant, with an inhibition percentage of, respectively, 70.63, 99.3 and 63.37% in the presence of, respectively, S. typhimurium TA100, S. typhimurium TA1538 and S. typhimurium TA104 strains at a concentration of 250 µg/plate after metabolic activation (S9). Antioxidant capacity of the tested extract was evaluated using the enzymatic (xanthine/xanthine oxidase assay) and the nonenzymatic (2,2-diphenyl-1-picrylhydrazyl) system. G extract exhibited high antioxidant activity.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Mutagênicos/farmacologia , Extratos Vegetais/farmacologia , Tumores de Planta , Plumbaginaceae/química , Aflatoxina B1/antagonistas & inibidores , Análise de Variância , Antracenos , Compostos de Bifenilo , Metanossulfonato de Metila , Microssomos/efeitos dos fármacos , Fenilenodiaminas/antagonistas & inibidores , Picratos , Salmonella typhimurium/efeitos dos fármacos , Azida Sódica/metabolismo , Especificidade da Espécie , Tunísia
2.
Cancer Cell Int ; 12(1): 26, 2012 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-22686580

RESUMO

BACKGROUND: The digallic acid (DGA) purified from Pistacia lentiscus. L fruits was investigated for its antiproliferative and apoptotic activities on human lymphoblastoid TK6 cells. METHODS: We attempt to characterize the apoptotic pathway activated by DGA. Apoptosis was detected by DNA fragmentation, PARP cleavage and by evaluating caspase activities. RESULTS: The inhibition of lymphoblastoid cell proliferation was noted from 8.5 µg/ml of DGA. The induction of apoptosis was confirmed by DNA fragmentation and PARP cleavage. We have demonstrated that DGA induces apoptosis by activating the caspase-8 extrinsic pathway. Caspase-3 was also activated in a dose dependent manner. CONCLUSION: In summary, DGA exhibited an apoptosis inductor effect in TK6 cells revealing thus its potential as a cancer-preventive agent.

3.
Nutr Cancer ; 64(7): 1095-102, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23061911

RESUMO

In this report, the ethyl acetate extract and its major constituent, isorhamnetin 3-o-robinobioside (I3-O-Rob), from Nitraria retusa (N. Retusa) leaf extracts were evaluated for their ability to induce apoptosis in human lymphoblastoid cells (TK6). Apoptosis of TK6 cell line was carried out using DNA fragmentation, poly ADP-ribose polymerase (PARP) cleavage with reference to caspase-3 activity. These tested products, from N. Retusa, enhanced the apoptosis effects in the tested cancer cell line. This result was confirmed by DNA fragmentation and PARP cleavage indicating a release of caspase-3 level. Our results indicate that the original ethyl acetate extract and the I3-O-Rob have a great antiproliferative effect on human lymphoblastoid cells (TK6), which may be due to their involvement in the apoptotic pathway.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Magnoliopsida/química , Extratos Vegetais/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Glicosídeos/farmacologia , Humanos , Folhas de Planta/química , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Quercetina/análogos & derivados , Quercetina/farmacologia
4.
BMC Complement Altern Med ; 12: 135, 2012 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22913434

RESUMO

BACKGROUND: In this report, the isorhamnetin 3-o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, were evaluated for their ability to induce antioxidant and antigenotoxic effects in human chronic myelogenous leukemia cell line. METHODS: Nitraria retusa products properties were carried out by firstly evaluating their effects against lipid peroxidation induced by H2O2, using the thiobarbituric acid reactive substances species (TBARS) assay, and proceeding to the assay of cellular antioxidant activity, then doing the comet assay. RESULTS: The isorhamnetin 3-o-robinobioside showed a protective effect against lipid peroxidation induced by H2O2. The same natural compound and ethyl acetate extract inhibited oxidation induced by 2,2'-azobis (2-amidinopropane) dihydrochloride in human chronic myelogenous leukemia cells with respectively 50% inhibitory concentration values of 0.225 mg/ml and 0.31 mg/ml, reflecting a significant antioxidant potential. The same two products inhibited the genotoxicity induced by hydroxyl radicals in the same human cell line (by 77.77% at a concentration of 800 µg/ml and by 80.55% at a concentration of 1000 µg/ml respectively). CONCLUSIONS: The isorhamnetin 3- o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, have a great antioxidant and antigenotoxic potential on human chronic myelogenous leukemia cell line K562.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/farmacologia , Quercetina/análogos & derivados , Antimutagênicos/isolamento & purificação , Antimutagênicos/uso terapêutico , Antioxidantes/isolamento & purificação , Antioxidantes/uso terapêutico , Linhagem Celular , Glicosídeos/uso terapêutico , Humanos , Peróxido de Hidrogênio , Concentração Inibidora 50 , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Nigéria , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Quercetina/isolamento & purificação , Quercetina/farmacologia , Quercetina/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
5.
Phytother Res ; 26(3): 387-91, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21780210

RESUMO

The antioxidant and apoptotic activities of digallic acid, isolated from the fruits of Pistascia lentiscus, were investigated. The study demonstrated that digallic acid possessed pro-apoptotic effects, as shown by provoking DNA fragmentation of K562 cells. It also revealed a significant antioxidant potential and effective scavenging activity against 2,2-diphenyl-1-picrylhdrazyl (DPPH·) and O2·â» radicals, and reduced cupric ions. We conclude that this integrated approach to apoptotic and antioxidant assessment may be useful to maximize the beneficial effects associated with using P. lentiscus derivatives as medicinal and dietary compounds.


Assuntos
Antioxidantes/química , Apoptose , Depsídeos/farmacologia , Ácido Gálico/análogos & derivados , Pistacia/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/química , Fragmentação do DNA , Depsídeos/química , Frutas/química , Ácido Gálico/química , Ácido Gálico/farmacologia , Humanos , Células K562 , Picratos/química , Extratos Vegetais/química , Riboflavina/química , Superóxido Dismutase/química , Sais de Tetrazólio/química
6.
Cancer Cell Int ; 11(1): 37, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-22040460

RESUMO

BACKGROUND: In this report the phytochemical profile of Nitraria. Retusa (N. Retusa) leaf extracts were identified and their ability to induce apoptosis in human chronic myelogenous erythroleukaemia (K562) was evaluated. METHODS: Apoptosis of the human chronic myelogenous erythroleukaemia (K562) was evidenced by investigating DNA fragmentation, PARP cleavage and caspases 3 and 8 inducing activities, in the presence of N. retusa extracts. RESULTS: Our study revealed that the tested extracts from N. Retusa contain many useful bioactive compounds. They induced in a time-dependent manner the apoptosis the tested cancerous our cell line. This result was confirmed by ladder DNA fragmentation profile and PARP cleavage, as well as a release in caspase-3 and caspase-8 level. CONCLUSION: Our results indicate that the tested compounds have a significant antiproliferative effect which may be due to their involvement in the induction of the extrinsic apoptosic pathway.

7.
J Appl Toxicol ; 30(6): 551-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20809543

RESUMO

Antioxidant activity of isorhamnetin 3-O-neohesperidoside, isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit xanthine oxidase activity and to scavenge the free radical 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS(.-)) diammonium salt. Antigenotoxic activity was assessed using the SOS chromotest assay. This compound has the ability to scavenge the ABTS(.+) radical by a hydrogen donating mechanism. We also envisaged the study of the antioxidant effect of this compound by the enzymatic xanthine/xanthine oxidase (X/XOD) assay. Results indicated that isorhamnetin 3-O-neohesperidoside was a potent inhibitor of xanthine oxidase and superoxide anion scavengers. Moreover, this compound induced an inhibitory activity against nifuroxazide and aflatoxine B1 (AFB1) induced genotoxicity. Taken together, these observations provide evidence that isorhamnetin 3-O-neohesperidoside isolated from the leaves of A. salicina is able to protect cells against the consequences of oxidative stress.


Assuntos
Acacia/química , Aflatoxina B1/toxicidade , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Hidroxibenzoatos/toxicidade , Nitrofuranos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Antimutagênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Enzimas Reparadoras do DNA/metabolismo , Relação Dose-Resposta a Droga , Flavonóis/isolamento & purificação , Flavonóis/farmacologia , Radicais Livres/química , Microssomos Hepáticos/efeitos dos fármacos , Testes de Mutagenicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Ratos , Xantina Oxidase/antagonistas & inibidores
8.
Drug Chem Toxicol ; 33(1): 20-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19995267

RESUMO

The in vitro antiproliferative, apoptotic, and antioxidant activities from leaf extracts of Moricandia arvensis, which are used in traditional cooking and medicines, were investigated. The MTT assay revealed that only TOF (total oligomer flavonoids), ethyl acetate (EA), chloroform (Chl), and petroleum ether (PE) extracts inhibited the proliferation of K562 cells. Apoptosis plays a very important role in the treatment of cancer by promoting the apoptosis of cancer cells and limiting the concurrent death of normal cells. Thus, the possible effects of M. arvensis extracts on the induction of apoptosis in human leukemic cells (K562 cells) were investigated. The electrophoretic analysis of DNA fragmentation confirms that TOF, Chl, PE, and EA extracts provoke DNA fragmentation. Using the lipid peroxidation inhibitory assay, the antioxidant capacity of M. arvensis extracts was evaluated by the ability of each extract to inhibit malondialdehyde formation. It was revealed that EA and TOF extracts are the most active in scavenging the hydroxyl radicals.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Brassicaceae/química , Leucemia Eritroblástica Aguda/tratamento farmacológico , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Eletroforese em Gel de Ágar , Humanos , Células K562 , Leucemia Eritroblástica Aguda/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Folhas de Planta , Solventes/química
9.
Chem Biodivers ; 7(7): 1754-63, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20658663

RESUMO

The mutagenic and antimutagenic effects of the essential oil extracted from the aerial parts of Teucrium ramosissimum were evaluated by the bacterial reverse mutation assay in Salmonella typhimurium TA98, TA100, and TA1535, with and without exogenous metabolic activation (S9 fraction). The T. ramosissimum essential oil showed no mutagenic effect. In contrast, our results established that it possessed antimutagenic effects against sodium azide (SA), aflatoxin B1 (AFB1), benzo[a]pyrene (B[a]P), and 4-nitro-o-phenylenediamine (NOPD). The antioxidant capacity of the tested essential oil was evaluated using enzymatic, i.e., the xanthine/xanthine oxidase (X/XOD) assay, and nonenzymatic systems, i.e., the nitro-blue tetrazolium (NBT)/riboflavin and the DPPH assays. A moderate free radical-scavenging activity was observed towards DPPH(.) and O2(.-). In contrast, T. ramosissimum essential oil showed no effect for all the tested concentrations in the X/XOD assay.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Teucrium/química , Antimutagênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/metabolismo , Testes de Mutagenicidade , Mutação/efeitos dos fármacos , Óleos Voláteis/isolamento & purificação , Picratos/metabolismo , Componentes Aéreos da Planta/química , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Xantina Oxidase/metabolismo
10.
Iran J Pharm Res ; 19(1): 282-291, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32922487

RESUMO

In the present work, chemical investigation of the aerial parts of Phlomis bovei de Noé an endemic species from Algeria, led to the isolation and identification of seven known compounds including five flavones glycosides: Chrysoeriol 7-O-(3''-(E et Z)-p-coumaroyl)-ß-glucoside (1), terniflorin (apigenin-7-O-(6''-E-p-coumaroyl)glucoside) (3), apigenin-7-O-(6''-(5'''-methoxy-coumaryl) glucoside (4), apigenin 7-O-(3″-p-coumaryl)glucoside (5), hispidulin-7-O-glucuronide (6) and two cinnamic acid derivatives: p-coumaric acid methyl ester (E et Z) (2), chlorogenic acid (7). Compound 4 is described for the first time in the species bovei de Noé, the genus Phlomis and the Lamiaceae family. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. Some pure compounds and extracts have been evaluated for their antioxidant activities through different methods: DPPH and ABTS assays as well as CUPRAC assay. Genotoxic and antigenotoxic activities of pure compounds were also evaluated in-vitro on Escherichia coli PQ37 cells by the SOS Chromotest.

11.
Toxicol In Vitro ; 23(1): 166-75, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19015021

RESUMO

The mutagenic potential of total aqueous, total oligomers flavonoids (TOF), ethyl acetate (EA), chloroform (Chl), petroleum ether (PE) and methanol (MeOH) extracts from aerial parts of Moricandia arvensis was assessed using Ames Salmonella tester strains TA100 and TA1535 with and without metabolic activation (S9), and using plasmid pBluescript DNA assay. None of the different extracts produced a mutagenic effect, except aqueous extract when incubated with Salmonella typhimurium TA100 after metabolic activation. Likewise, the antimutagenicity of the same extracts was tested using the "Ames test". Our results showed that M. arvensis extracts possess antimutagenic effects against sodium azide (SA) in the two tested Salmonella assay systems, except metabolized aqueous and PE extracts when tested with S. typhimurium TA100 assay system. Different extracts were also found to be effective in protecting plasmid DNA against the strand breakage induced by hydroxyl radicals, except PE and aqueous extracts. Antioxidant capacity of the tested extracts was evaluated using the enzymatic (xanthine/xanthine oxidase assay) (X/XOD) and the non enzymatic (NBT/Riboflavine assay) systems. TOF extract was the more effective one in inhibiting both xanthine oxidase activity and NBT reduction.


Assuntos
Antimutagênicos/toxicidade , Brassicaceae/química , Medicinas Tradicionais Africanas , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Antimutagênicos/classificação , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Testes de Mutagenicidade , Mutagênicos/classificação , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Azida Sódica/toxicidade , Superóxidos/metabolismo
12.
Drug Chem Toxicol ; 32(4): 372-80, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19793030

RESUMO

The Salmonella typhimurium/microsome assay is a widely used bacterial genotoxicity assay to test potential carcinogens. The aim of this work was to evaluate the mutagenic and antimutagenic activities with and without the addition of an extrinsic metabolic activation system of essential oils obtained from an aerial part of Pituranthos chloranthus harvested from different stations in Tunisia. The oils showed no mutagenicity when tested with S. typhimurium strains TA98, TA100, and TA1535. On the other hand, we showed that these essential oils reduced significantly Benzo [a] pyrene (B[a] P) and sodium-azide-induced mutagenicity. The scavenging capacity of these essential oils was also estimated by evaluating the inhibition of DPPH radical. Essential oils harvested at Medenine and Gabes in November were more effective in scavenging activity. The essential oils were tested for their antimicrobial properties against five different bacteria, and were found to be weakly active, with MIC and MBC values in the range 0.6-4 and 2.2-5 mg/mL, respectively.


Assuntos
Antibacterianos/farmacologia , Antimutagênicos/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Mutagênicos/farmacologia , Óleos Voláteis/química , Anti-Infecciosos/farmacologia , Bactérias , Sequestradores de Radicais Livres/farmacologia , Magnoliopsida , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Mutação , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Salmonella typhimurium/efeitos dos fármacos
13.
Drug Chem Toxicol ; 32(1): 38-46, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19514937

RESUMO

The lyophilized infusion, the methanol, the ethyl acetate, and the total oligomer flavonoid (TOF)-enriched extracts prepared from the dried leaves of Phlomis crinita Cav. ssp. mauritanica Munby were investigated for the contents of flavonoids, tannins, coumarines and steroids. Antibacterial activity was investigated toward five bacterial strains. An inhibitory effect was observed against Staphyllococcus aureus and Enterococcus feacalis, and the minimal inhibitory concentrations ranged from 2.5 to 5 mg/mL of extract. The tested extracts exhibit an important free radical scavenging activity toward the 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical; with IC(50) values of 30.5, 6, 32, and 31.5 microg/mL, respectively, in the presence of lyophilized infusion, the TOF, the methanol, and the ethyl acetate extracts. Genotoxic and antigenotoxic properties of the different extracts were studied by using the SOS chromotest with Escherichia coli PQ37. The lyophilized infusion and TOF extracts obtained from P. crinita ssp. mauritanica showed no genotoxicity, whereas methanol and ethyl acetate extracts are considered as marginally genotoxic. On the other hand, we showed that each extract inhibited the mutagenicity induced by aflatoxin B1 (AFB1) (10 microg/assay) and nifuroxazide (NF) (10 microg/assay). The ethyl acetate extract showed the strongest level of protection toward the genotoxicity induced by both directly and indirectly genotoxic NF and AFB1. These tests proved that the lyophilized infusion possesses an antiradical activity likewise, it showed no genotoxic effect; that is why we choose this extract to assess its antiulcerogenic activity by using an ethanol-induced ulcerogenesis model in the rat. This test demonstrates that 300 mg/kg of a P. crinita ssp. mauritanica lyophilized infusion was more effective than the reference compound, cimetidine.


Assuntos
Antibacterianos/farmacologia , Antiulcerosos/farmacologia , Phlomis/química , Extratos Vegetais/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/isolamento & purificação , Antiulcerosos/administração & dosagem , Antiulcerosos/isolamento & purificação , Antimutagênicos/administração & dosagem , Antimutagênicos/isolamento & purificação , Antimutagênicos/farmacologia , Cimetidina/farmacologia , Feminino , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Liofilização , Concentração Inibidora 50 , Masculino , Testes de Sensibilidade Microbiana , Testes de Mutagenicidade , Extratos Vegetais/administração & dosagem , Folhas de Planta , Ratos
14.
Drug Chem Toxicol ; 32(2): 139-49, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19514950

RESUMO

Antioxidant activity of Acacia salicina extracts was determined by the ability of each extract to inhibit lipid peroxidation, to protect against DNA strand scission induced by hydroxyl radicals, and to scavenge the free radical, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(*+)). The IC(50) values of the inhibitory activity toward lipid peroxidation of total oligomer flavonoids (TOF), methanol, ethyl acetate, and aqueous extracts were respectively 28, 52, 472, and 480 microg/mL. All extracts have the ability to scavenge the ABTS(*+) radical by a hydrogen-donating mechanism and to protect pKS plasmid DNA against hydroxyl radicals- induced DNA damage. An assay for the ability of A. salicina extracts to prevent mutations induced by various mutagens in Salmonella typhimurium TA102 and TA104 cells was conducted. TOF, methanol, ethyl acetate, and aqueous extracts from leaf parts of A. salicina showed no mutagenicity either with or without the metabolic enzymes preparation (S9). Protection against methylmethanesulfonate-induced mutagenicity was observed for TOF, methanol, and ethyl acetate extracts. Likewise, all extracts exhibited a high inhibition level of the Ames response induced by the indirect mutagen, 2-aminoanthracene. The antigenotoxic activity could be ascribed, at least in part, to their antioxidant properties, but we cannot exclude additionally mechanisms. Thus, A. salicina may serve as an ideal candidate for a cost- effective, readily exploitable natural phytochemical compound.


Assuntos
Acacia/química , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Citoproteção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Flavonoides/farmacologia , Sequestradores de Radicais Livres , Humanos , Células K562 , Fitoterapia , Substâncias Protetoras/farmacologia
15.
Drug Chem Toxicol ; 32(3): 258-67, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19538023

RESUMO

Antioxidant activity of isorhamnetin 3-O neohesperidoside (I3ON), isolated from the leaves of Acacia salicina, was determined by the ability of this compound to inhibit lipid peroxidation and to protect against hydroxyl radical-induced DNA damage in pKS plasmid DNA and Escherichia coli cultures. Antigenotoxic activity was assessed by using the comet assay. The IC(50) value of the inhibitory activity toward lipid peroxidation by I3ON is 0.6 mM. This compound was also able to protect against hydroxyl radical-induced DNA damage in pKS plasmid DNA. Moreover, this compound induced an inhibitory activity toward H2O2-induced genotoxicity. The protective effect exhibited by this molecule was also determined by analysis of gene expression as a response to an oxidative stress, using a cDNA microarray. Transcription of several genes related to the antioxidant system (HMOX2 and TXNL) and to the DNA repair pathway (XPC, POLD1, POLD2, PCNA, DDIT3, APEX, and LIG4) were upregulated after incubation with I3ON. Taken together, these observations provide evidence that the I3ON, isolated from the leaves of A. salicina, is able to protect cells against oxidative stress.


Assuntos
Acacia/química , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaio Cometa , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Flavonóis/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/toxicidade , Radical Hidroxila/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Oxidantes/toxicidade , Estresse Oxidativo/genética , Folhas de Planta/química , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética , Regulação para Cima/efeitos dos fármacos
16.
C R Biol ; 331(1): 48-55, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18187122

RESUMO

In the present investigation, methanolic extracts from shoots and roots of Tunisian Nigella sativa were assayed for their antioxidant and antimutagenic activities. The phenolic composition of the methanolic extracts was determined by RP-HPLC. The predominant phenolic compound was vanillic acid with a mean concentration of 143.21 and 89.94 mg per 100 g dry weight of shoots and roots, respectively. Shoots and roots showed comparable and strong superoxide scavenger activity; however, shoots exhibited higher DPPH radical scavenging, reducing and chelating activities than roots. Mutagenic and antimutagenic activities were determined by using the Ames test. Shoots and roots demonstrated important antimutagenic effects. Roots exhibited stronger activity than shoots with an inhibition percentage of 71.32%.


Assuntos
Nigella sativa/química , Fenóis/análise , Raízes de Plantas/química , Brotos de Planta/química , Antimutagênicos/análise , Antioxidantes/análise , Antioxidantes/farmacologia , Quelantes , Cromatografia Líquida de Alta Pressão , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/farmacologia , Metanol , Mutagênicos/análise , Extratos Vegetais/química , Tunísia , Ácido Vanílico/análise
17.
Chem Biol Interact ; 174(1): 1-10, 2008 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-18511029

RESUMO

The effect of extracts obtained from Rhamnus alaternus L. leaves on genotoxicity and SOS response induced by aflatoxin B(1) (10 microg/assay) as well as nifuroxazide (20 microg/assay) was investigated in a bacterial assay system, i.e., the SOS chromotest with Escherichia coli PQ37. The evaluation of the mutagenic and antimutagenic actions of the same extracts against the sodium azide (1.5 microg/plate)-induced mutagenicity was assayed using the Salmonella typhimurium assay system. The R. alaternus tested extracts exhibited no genotoxicity either with or without the external S9 activation mixture. However, all the extracts, particularly aqueous extract (A) and its chloroformic fraction (A(2)) significantly decreased the genotoxicity induced by aflatoxin B(1) and nifuroxazide. Moreover, the different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA1535 and TA1538 either with or without the S9 mix. Aqueous extract as well as its A(2) fraction exhibited the highest level of protection towards the direct mutagen, sodium azide-induced response in TA1535 strain with mutagenicity inhibition percentages of 83.6% and 91.4%, respectively, at a dose of 250 microg/plate. The results obtained by the Ames test assay confirm those of SOS chromotest. These same active extracts exhibited high xanthine oxidase (XOD) inhibiting with respective IC(50) values of 208 and 137 microg/ml, and superoxide anion-scavenging effects (IC(50) values of 132 and 117 microg/ml) when tested in the XOD enzymatic assay system. Our findings emphasize the potential of R. alaternus to prevent mutations and also its antioxidant effect.


Assuntos
Aflatoxina B1/toxicidade , Antioxidantes/farmacologia , Hidroxibenzoatos/toxicidade , Mutagênese/efeitos dos fármacos , Nitrofuranos/toxicidade , Extratos Vegetais/farmacologia , Rhamnus/química , Azida Sódica/toxicidade , Escherichia coli/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Testes de Mutagenicidade , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Superóxidos/metabolismo , Xantina Oxidase/antagonistas & inibidores
18.
Toxicol In Vitro ; 22(5): 1264-72, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18515041

RESUMO

The total oligomers flavonoids (TOF), chloroform, petroleum ether and aqueous extracts from Acacia salicina, were investigated for the antioxidative, cytotoxic, antimutagenic and antigenotoxic activities. The viability of K562 cells were affected by all extracts after 48 h exposure. Our results showed that A. salicina extracts have antigenotoxic and/or antimutagenic activities. TOF and chloroform extracts exhibit antioxidant properties, expressed by the capacity of these extracts to inhibit xanthine oxidase activity. To further explore the mechanism of action of A. salicina extracts, we characterized expression profiles of genes involved in antioxidant protection and DNA repair in the human lymphoblastic cell line K562 exposed to H2O2. Transcription of several genes related to the thioredoxin antioxidant system and to the DNA base-excision repair pathway was up-regulated after incubation with chloroform, TOF and petroleum ether extracts. Moreover genes involved in the nucleotide-excision repair pathway and genes coding for catalase and Mn-superoxide-dismutase, two important antioxidant enzymes, were induced after incubation with the chloroform extract. Taken together, these observations provide evidence that the chloroform and TOF extracts of A. salicina leaves contain bioactive compounds that are able to protect cells against the consequences of an oxidative stress.


Assuntos
Acacia/química , Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Medicina Tradicional , Oxidantes/farmacologia , Animais , Linhagem Celular Tumoral , Ensaio Cometa , DNA/efeitos dos fármacos , Combinação de Medicamentos , Flavonoides/química , Formazans/metabolismo , Perfilação da Expressão Gênica , Genes Bacterianos/efeitos dos fármacos , Humanos , Células K562/efeitos dos fármacos , Células K562/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Extratos Vegetais/farmacologia , Ratos , Proteína S9 Ribossômica , Proteínas Ribossômicas/efeitos dos fármacos , Proteínas Ribossômicas/metabolismo , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Sais de Tetrazólio/metabolismo
19.
Toxicol In Vitro ; 22(3): 567-81, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18222061

RESUMO

Antioxidant activity of myricetin-3-o-galactoside and myricetin-3-o-rhamnoside, isolated from the leaves of Myrtus communis, was determined by the ability of each compound to inhibit xanthine oxidase activity, lipid peroxidation and to scavenge the free radical 1,1-diphenyl-2-picrylhydrazyl. Antimutagenic activity was assessed using the SOS chromotest and the Comet assay. The IC50 values of lipid peroxidation by myricetin-3-o-galactoside and myricetin-3-o-rhamnoside are respectively 160 microg/ml and 220 microg/ml. At a concentration of 100 microg/ml, the two compounds showed the most potent inhibitory effect of xanthine oxidase activity by respectively, 57% and 59%. Myricetin-3-o-rhamnoside was a very potent radical scavenger with an IC50 value of 1.4 microg/ml. Moreover, these two compounds induced an inhibitory activity against nifuroxazide, aflatoxine B1 and H2O2 induced mutagenicity. The protective effect exhibited by these molecules was also determined by analysis of gene expression as response to an oxidative stress using a cDNA micro-array. Myricetin-3-o-galactoside and myricetin-3-o-rhamnoside modulated the expression patterns of cellular genes involved in oxidative stress, respectively (GPX1, TXN, AOE372, SEPW1, SHC1) and (TXNRD1, TXN, SOD1 AOE372, SEPW1), in DNA damaging repair, respectively (XPC, LIG4, RPA3, PCNA, DDIT3, POLD1, XRCC5, MPG) and (TDG, PCNA, LIG4, XRCC5, DDIT3, MSH2, ERCC5, RPA3, POLD1), and in apoptosis (PARP).


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Flavonoides/farmacologia , Galactosídeos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Manosídeos/farmacologia , Myrtus/química , Compostos de Bifenilo , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Reparo do DNA/efeitos dos fármacos , DNA Complementar/biossíntese , DNA Complementar/genética , Inibidores Enzimáticos/farmacologia , Humanos , Processamento de Imagem Assistida por Computador , Hibridização In Situ , Células K562 , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Mutagenicidade , Análise de Sequência com Séries de Oligonucleotídeos , Picratos/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Xantina Oxidase/antagonistas & inibidores
20.
Bioresour Technol ; 99(18): 9004-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18538563

RESUMO

The in vitro antibacterial, antioxidant, cytotoxic and apoptotic activities from tubers extracts of Cyperus rotundus (Cyperaceae) were investigated. Antibacterial activity of different extracts was evaluated against five bacterial reference strains. A marked inhibitory effect was observed against Salmonella enteritidis, Staphylococcus aureus and Enterococcus faecalis with total oligomers flavonoids (TOFs) and ethyl acetate extracts. In addition to their antibacterial activity, the same extracts showed a significant ability to inhibit nitroblue tetrazolium reduction by the superoxide radical in a non-enzymatic superoxide generating system. Apoptosis, a highly organized physiological mechanism to eliminate injured or abnormal cells, is also implicated in multistage carcinogenesis. It was observed that TOF and ethyl acetate extracts suppressed growth and proliferation of L1210 cells derived from murine lymphoblastic leukaemia. Morphological features of treated cells and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. This study confirms that TOF and ethyl acetate extracts of C.rotundus possess antibacterial and antioxidant properties and provoke DNA fragmentation, a sign of induction of apoptosis. These results were correlated with chemical composition of the tested extracts.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Cyperus/metabolismo , Extratos Vegetais/farmacologia , Tubérculos/metabolismo , Animais , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cyperus/química , Fragmentação do DNA/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Superóxidos/metabolismo
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