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1.
BMC Plant Biol ; 22(1): 40, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35045819

RESUMO

BACKGROUND: Most plants encounter water stress at one or more different stages of their life cycle. The maintenance of genetic stability is the integral component of desiccation tolerance that defines the storage ability and long-term survival of seeds. Embryonic axes of desiccation-sensitive recalcitrant seeds of Acer pseudoplatnus L. were used to investigate the genotoxic effect of desiccation. Alkaline single-cell gel electrophoresis (comet assay) methodology was optimized and used to provide unique insights into the onset and repair of DNA strand breaks and 8-oxo-7,8-dihydroguanine (8-oxoG) formation during progressive steps of desiccation and rehydration. RESULTS: The loss of DNA integrity and impairment of damage repair were significant predictors of the viability of embryonic axes. In contrast to the comet assay, automated electrophoresis failed to detect changes in DNA integrity resulting from desiccation. Notably, no significant correlation was observed between hydroxyl radical (Ù OH) production and 8-oxoG formation, although the former is regarded to play a major role in guanine oxidation. CONCLUSIONS: The high-throughput comet assay represents a sensitive tool for monitoring discrete changes in DNA integrity and assessing the viability status in plant germplasm processed for long-term storage.


Assuntos
Acer/genética , Ensaio Cometa/métodos , Reparo do DNA , Estresse Oxidativo , Sementes/genética , Acer/química , Acer/crescimento & desenvolvimento , Soluções Tampão , Fragmentação do DNA , DNA-Formamidopirimidina Glicosilase/metabolismo , Dessecação , Guanosina/análogos & derivados , Guanosina/genética , Guanosina/metabolismo , Análise de Componente Principal , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
2.
Mini Rev Med Chem ; 20(1): 39-53, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30854962

RESUMO

Chronic Myeloid Leukemia (CML) represents 15-20% of all new cases of leukemia and is characterized by an uncontrolled proliferation of abnormal myeloid cells. Currently, the first-line of treatment involves Tyrosine Kinase Inhibitors (TKIs), which specifically inhibits the activity of the fusion protein BCR-ABL. However, resistance, mainly due to mutations, can occur. In the attempt to find more effective and less toxic therapies, several approaches are taken into consideration such as research of new anti-leukemic drugs and "combination chemotherapy" where different drugs that act by different mechanisms are used. Here, we reviewed the molecular mechanisms of CML, the main mechanisms of drug resistance and current strategies to enhance the therapeutic effect of TKIs in CML. Despite major advances in CML treatment, new, more potent anticancer drugs and with fewer side effects are needed. Marine organisms, and particularly seaweed, have a high diversity of bioactive compounds with some of them having anticancer activity in several in vitro and in vivo models. The state-of-art suggests that their use during cancer treatment may improve the outcome. We reviewed here the yet few data supporting anti-leukemic activity of some carotenoids and phlorotannins in some leukemia models. Also, strategies to overcome drug resistance are discussed, particularly the combination of conventional drugs with natural compounds.


Assuntos
Antineoplásicos/farmacologia , Carotenoides/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Alga Marinha/química , Taninos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Carotenoides/química , Carotenoides/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Taninos/química , Taninos/uso terapêutico
3.
Environ Toxicol ; 35(4): 507-517, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31804023

RESUMO

Doxorubicin (Dox) is one of the most successful anticancer drugs in use. However, chemoresistance is one of the main limitations that patients face. Therefore, development of new strategies to improve the efficacy of Dox is needed. Marine-derived fungi are especially promising sources of new anticancer compounds. In this work, antitumor activity of crude ethyl extract of the cultures of the marine-derived fungus Neosartorya siamensis KUFA 0017 (NS), combined with Dox, was evaluated in six cancer cell lines. To evaluate possible mechanisms involved in the eventual improvement of Dox's cytotoxicity by NS extract, effects on DNA damage, cell death, ultrastructural modifications, and intracellular accumulation of Dox were assessed. The NS extract demonstrated a significant enhancement of Dox's cytotoxic activity in A549 cells, inducing DNA damage, cell death, and intracellular accumulation of Dox. Additionally, the cytotoxic effect of eight compounds, isolated from this extract, that is, 2,4-dihydroxy-3-methylacetophenone-(C1), nortryptoquivaline-(C2), chevalone C-(C3), tryptoquivaline H-(C4), fiscalin A-(C5), epi-fiscalin-C (C6), epi-neofiscalin A-(C7), and epi-fiscalin A-(C8), alone and combined with Dox was also evaluated in lung cancer cells. The cytotoxic effect of Dox was potentiated by all the isolated compounds (except C1) in A549 cells. Therefore, we concluded that NS extract potentiated cytotoxicity by inhibiting cell proliferation, increasing intracellular accumulation of Dox, and inducing cell death (possibly by an autophagic process). The isolated compounds also enhanced the activity of Dox, supporting the potential of this sort of combination. These data call for further studies to characterize drug interactions and underlying mechanisms.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Produtos Biológicos/farmacologia , Doxorrubicina/farmacologia , Neosartorya/metabolismo , Células A549 , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Humanos , Indóis/isolamento & purificação , Indóis/metabolismo , Indóis/farmacologia , Neoplasias Pulmonares/patologia , Quinazolinas/isolamento & purificação , Quinazolinas/metabolismo , Quinazolinas/farmacologia
4.
Mar Drugs ; 17(8)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366127

RESUMO

Preussin, a hydroxyl pyrrolidine derivative isolated from the marine sponge-associated fungus Aspergillus candidus KUFA 0062, displayed anticancer effects in some cancer cell lines, including MCF7. Preussin was investigated for its cytotoxic and antiproliferative effects in breast cancer cell lines (MCF7, SKBR3, and MDA-MB-231), representatives of major breast cancers subtypes, and in a non-tumor cell line (MCF12A). Preussin was first tested in 2D (monolayer), and then in 3D (multicellular aggregates), cultures, using a multi-endpoint approach for cytotoxicity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), resazurin and lactate dehydrogenase (LDH)) and proliferative (5-bromo-2'-deoxyuridine (BrdU)) assays, as well as the analysis of cell morphology by optical/electron microscopy and immunocytochemistry for caspase-3 and ki67. Preussin affected cell viability and proliferation in 2D and 3D cultures in all cell lines tested. The results in the 3D culture showed the same tendency as in the 2D culture, however, cells in the 3D culture were less responsive. The effects were observed at different concentrations of preussin, depending on the cell line and assay method. Morphological study of preussin-exposed cells revealed cell death, which was confirmed by caspase-3 immunostaining. In view of the data, we recommend a multi-endpoint approach, including histological evaluation, in future assays with the tested 3D models. Our data showed cytotoxic and antiproliferative activities of preussin in breast cancer cell lines in 2D and 3D cultures, warranting further studies for its anticancer potential.


Assuntos
Anisomicina/análogos & derivados , Antineoplásicos/farmacologia , Aspergillus/química , Neoplasias da Mama/tratamento farmacológico , Poríferos/microbiologia , Animais , Anisomicina/farmacologia , Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Células MCF-7
5.
J Toxicol Environ Health A ; 82(9): 537-549, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258008

RESUMO

Colorectal cancer (CRC) is one of the most frequently occurring carcinomas which require effective therapies. Fucosterol is a sterol present in marine brown seaweeds with several biological activities. However, the influence of fucosterol in CRC remains to be determined. Thus, the aim of this study was to examine the anticancer activity of fucosterol alone and in combination with 5-fluorouracil (5-Fu) on two human CRC cell lines (HCT116 and HT29) and compared with cytotoxicity in one normal colon fibroblast cell line (CCD-18co) in monolayer (2D). The effect of fucosterol alone or in combination with 5-Fu was further assessed using HT29 multicellular spheroids (3D). Data demonstrated that fucosterol alone or combined with 5-Fu decreased cell viability in HT29 cells in 2D cultures without inducing cytotoxic in normal colon cells. The combination, fucosterol, and 5-Fu, also inhibited cell proliferation, clonogenic potential and cell migration without producing cell death in 2D. In multicellular spheroids, the combination fucosterol plus 5-Fu at the same concentrations used in 2D was not effective demonstrating that under the tested conditions the 3D model was more resistant than the 2D model. Taken together, these findings suggest that fucosterol might be a promising alternative to enhance the cytotoxic and anti-invasive actions of 5-Fu in colon cancer cells without consequent major adverse effects in normal cells. Our results also reinforce the need to include more complex 3D culture models in the initial stages of drug screening.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/farmacologia , Estigmasterol/análogos & derivados , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Alga Marinha , Esferoides Celulares/efeitos dos fármacos , Estigmasterol/farmacologia
6.
Mar Drugs ; 16(4)2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29642369

RESUMO

A previously unreported bis-indolyl benzenoid, candidusin D (2e) and a new hydroxypyrrolidine alkaloid, preussin C (5b) were isolated together with fourteen previously described compounds: palmitic acid, clionasterol, ergosterol 5,8-endoperoxides, chrysophanic acid (1a), emodin (1b), six bis-indolyl benzenoids including asterriquinol D dimethyl ether (2a), petromurin C (2b), kumbicin B (2c), kumbicin A (2d), 2″-oxoasterriquinol D methyl ether (3), kumbicin D (4), the hydroxypyrrolidine alkaloid preussin (5a), (3S, 6S)-3,6-dibenzylpiperazine-2,5-dione (6) and 4-(acetylamino) benzoic acid (7), from the cultures of the marine sponge-associated fungus Aspergillus candidus KUFA 0062. Compounds 1a, 2a-e, 3, 4, 5a-b, and 6 were tested for their antibacterial activity against Gram-positive and Gram-negative reference and multidrug-resistant strains isolated from the environment. Only 5a exhibited an inhibitory effect against S. aureus ATCC 29213 and E. faecalis ATCC29212 as well as both methicillin-resistant S. aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains. Both 1a and 5a also reduced significant biofilm formation in E. coli ATCC 25922. Moreover, 2b and 5a revealed a synergistic effect with oxacillin against MRSA S. aureus 66/1 while 5a exhibited a strong synergistic effect with the antibiotic colistin against E. coli 1410/1. Compound 1a, 2a-e, 3, 4, 5a-b, and 6 were also tested, together with the crude extract, for cytotoxic effect against eight cancer cell lines: HepG2, HT29, HCT116, A549, A 375, MCF-7, U-251, and T98G. Except for 1a, 2a, 2d, 4, and 6, all the compounds showed cytotoxicity against all the cancer cell lines tested.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Aspergillus/química , Bactérias/efeitos dos fármacos , Poríferos/microbiologia , Animais , Anisomicina/análogos & derivados , Anisomicina/química , Anisomicina/isolamento & purificação , Anisomicina/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Farmacorresistência Bacteriana/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Pirrolidinas/química , Pirrolidinas/isolamento & purificação , Pirrolidinas/farmacologia , Compostos de Terfenil/química , Compostos de Terfenil/isolamento & purificação
7.
J Toxicol Environ Health A ; 80(13-15): 776-787, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28850007

RESUMO

Colorectal cancer therapy with 5-fluorouracil (5-Fu) frequently become ineffective due to resistance to this drug; and thus other effective compounds are essential for therapy. It is well-known marine brown seaweeds contain antioxidant compounds the carotenoid fucoxanthin (Fx) and polyphenolic compound phloroglucinol (Ph) which exerted diverse biological activities including antioxidant and anticancer. The aim of this study was to determine the anticancer activities of Fx or Ph alone as well as combination of each chemical with 5-Fu on two human colorectal cancer cell lines (HCT116 and HT29), with comparison to responses in a normal colon cell line (CCD-18Co). Effects of these compounds on cell viability, induction of DNA damage, and cell death were evaluated using MTT assay, comet assay, nuclear condensation assay, and Western blot. 5-Fu decreased cell viability in a concentration-dependent manner in HCT116 and HT29 cells but was not cytotoxic in CCD-18Co cells. 5-Fu induced DNA damage in HCT116 cells with induction of cell death, while no marked effects on DNA damage and cell death were observed in HT29 cells. Fx or Ph alone also reduced cell viability in both cancer cell lines but no apparent cytotoxic effect in CCD-18Co cells, except for Fx at 50 and 100 µM. Diminished cell viability was accompanied by induction of DNA damage (by Fx) and induction of cell death (by Ph). In combination with 5-Fu, Fx at 10 µM (in HCT116 and HT29 cells), and Ph at 300 µM (in HT29 cells) enhanced the cytotoxic effect of 5-Fu; however, no marked cytotoxicity was noted in CCD-18Co cells. Since Fx and Ph alone reduced cancer cell line viability without an effect on normal cells and when in combination enhanced the cytotoxic effect of 5-Fu only in colon cancer cells, these compounds seem promising as anticancer agents.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Fluoruracila/farmacologia , Floroglucinol/farmacologia , Alga Marinha/química , Xantofilas/farmacologia , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Colo/efeitos dos fármacos , Quimioterapia Combinada , Fluoruracila/administração & dosagem , Células HCT116 , Células HT29 , Humanos , Floroglucinol/administração & dosagem , Xantofilas/administração & dosagem
8.
Pharmacognosy Res ; 9(Suppl 1): S92-S98, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29333049

RESUMO

BACKGROUND: Drug resistance is a major concern in the current chemotherapeutic approaches and the combination with natural compounds may enhance the cytotoxic effects of the anticancer drugs. Therefore, this study evaluated the cytotoxicity of crude ethyl extracts of six marine-derived fungi - Neosartorya tsunodae KUFC 9213 (E1), Neosartorya laciniosa KUFC 7896 (E2), Neosartorya fischeri KUFC 6344 (E3), Aspergillus similanensis KUFA 0013 (E4), Neosartorya paulistensis KUFC 7894 (E5), and Talaromyces trachyspermum KUFC 0021 (E6) - when combined with doxorubicin (Dox), in seven human cancer cell lines. MATERIALS AND METHODS: The antiproliferative activity was primarily assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. RESULTS: Two extracts, E1 and E2, demonstrated a significant enhancement of Dox's cytotoxicity in nonsmall cell lung cancer A549 cells. Accumulation of Dox in the nuclei increased when A549 cells were treated in combination with extracts E1 and E2, with induction of cell death observed by the nuclear condensation assay. The combination of E2 with Dox increased the DNA damage as detected by the comet assay. Ultrastructural observations by transmission electron microscopy suggest an autophagic cell death due to an increase of autophagic vesicles, namely with the combination of Dox with E1 and E2. CONCLUSION: These findings led to the conclusion that the fungal extracts E1 and E2 potentiate the anticancer action of Dox, through nuclear accumulation of Dox with induction of cell death mainly by cytotoxic autophagy. SUMMARY: Fungal extracts increase the cytotoxic activity of doxorubicin (Dox) in lung cancer cellsNuclear accumulation of Dox, DNA damage, and cell death as a mechanism of actionFungal extracts may potentiate the anticancer activity of conventional drugs.Abbreviations Used: A375: Human malignant melanoma cell line, A549: Human non small lung cancer cell line, DAPI: 4,6-Diamidino-2-phenylindole, DMEM: Dulbecco's Modified Eagle Medium, DMSO: Dimethylsulfoxide, Dox: Doxorubicin, DSBs: DNA double-strand breaks, E1: Neosartorya tsunodae KUFC 9213, E2: Neosartorya laciniosa KUFC 7896, E3: Neosartorya fischeri KUFC 6344, E4: Aspergillus similanensis KUFA 0013, E5: Neosartorya paulistensis KUFC 7894, E6: Talaromyces trachyspermum KUFC 0021, FBS: Fetal bovine serum, HCT116: Human colorectal carcinoma cell line, HEPES: (N-[2-hydroxyethyl] piperazine-N'- [2-ethane-sulfonic acid]), HepG2: Human hepatocellular carcinoma cell line, HT29: Human Caucasian colon adenocarcinoma Grade II cell line, IC50: Concentration of the extract or Dox that inhibits cell viability by 50%, LRP: Lung resistance-related protein, MCF7: Human breast adenocarcinoma cell line, MEM: Minimum Essential Medium Eagle, MRPs: Multidrug resistance-associated proteins, MTT: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, PBS: Phosphate-buffered saline, NSCLC: Nonsmall cell lung cancer, P-gp: P-glycoprotein, ROS: Reactive oxygen species, RPMI: Roswell Park Memorial Institute Medium, TEM: Transmission electron microscopy, U251: Human glioblastoma astrocytoma cell line.

9.
Phytother Res ; 30(2): 298-305, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26661587

RESUMO

Salvia officinalis and some of its isolated compounds have been found to be preventive of DNA damage and increased proliferation in vitro in colon cells. In the present study, we used the azoxymethane model to test effects of S. officinalis on colon cancer prevention in vivo. The results showed that sage treatment reduced the number of ACF formed only if administered before azoxymethane injection, demonstrating that sage tea drinking has a chemopreventive effect on colorectal cancer. A decrease in the proliferation marker Ki67 and in H2 O2 -induced and azoxymethane-induced DNA damage to colonocytes and lymphocytes were found with sage treatment. This confirms in vivo the chemopreventive effects of S. officinalis. Taken together, our results show that sage treatment prevented initiation phases of colon carcinogenesis, an effect due, at least in part, to DNA protection, and reduced proliferation rates of colon epithelial cell that prevent mutations and their fixation through cell replication. These chemopreventive effects of S. officinalis on colon cancer add to the many health benefits attributed to sage and encourage its consumption.


Assuntos
Anticarcinógenos/farmacologia , Neoplasias Colorretais/prevenção & controle , Dano ao DNA/efeitos dos fármacos , Extratos Vegetais/farmacologia , Salvia officinalis/química , Chás de Ervas , Focos de Criptas Aberrantes/patologia , Animais , Azoximetano , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Citocromo P-450 CYP2E1/metabolismo , Feminino , Ratos , Ratos Endogâmicos F344
10.
Free Radic Biol Med ; 60: 41-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23391575

RESUMO

O(6)-methylguanine (O(6)meG) is one of the most premutagenic, precarcinogenic, and precytotoxic DNA lesions formed by alkylating agents. Repair of this DNA damage is achieved by the protein MGMT, which transfers the alkyl groups from the O(6) position of guanine to a cysteine residue in its active center. Because O(6)meG repair by MGMT is a stoichiometric reaction that irreversibly inactivates MGMT, which is subsequently degraded, the repair capacity of O(6)meG lesions is dependent on existing active MGMT molecules. In the absence of active MGMT, O(6)meG is not repaired, and during replication, O(6)meG:T mispairs are formed. The MMR system recognizes these mispairs and introduces a gap into the strand. If O(6)meG remains in one of the template strands the futile MMR repair process will be repeated, generating more strand breaks (SBs). The toxicity of O(6)meG is, therefore, dependent on MMR and DNA SB induction of cell death. MGMT, on the other hand, protects against O(6)meG toxicity by removing the methyl residue from the guanine. Although removal of O(6)meG makes MGMT an important anticarcinogenic mechanism of DNA repair, its activity significantly decreases the efficacy of cancer chemotherapeutic drugs that aim at achieving cell death through the action of the MMR system on unrepaired O(6)meG lesions. Here, we report on a modification of the comet assay (CoMeth) that allows the qualitative assessment of O(6)meG lesions after their conversion to strand breaks in proliferating MMR-proficient cells after MGMT inhibition. This functional assay allows the testing of compounds with effects on O(6)meG levels, as well as on MGMT or MMR activity, in a proliferating cell system. The expression of MGMT and MMR genes is often altered by promoter methylation, and new epigenetically active compounds are being designed to increase chemotherapeutic efficacy. The CoMeth assay allows the testing of compounds with effects on O(6)meG, MGMT, or MMR activity. This proliferating cell system complements other methodologies that look at effects on these parameters individually through analytical chemistry or in vitro assays with recombinant proteins.


Assuntos
Ensaio Cometa , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Reparo do DNA/genética , DNA/genética , Guanina/análogos & derivados , Proteínas Supressoras de Tumor/metabolismo , Alquilantes/toxicidade , Animais , DNA/química , DNA/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Genoma , Guanina/isolamento & purificação , Guanina/metabolismo , Camundongos , Proteínas Supressoras de Tumor/genética
11.
Food Chem Toxicol ; 51: 80-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23000446

RESUMO

Diet may induce colon carcinogenesis through oxidative or alkylating DNA damage. However, diet may also contain anticarcinogenic compounds that contribute to cancer prevention. DNA damage prevention and/or induction of repair are two important mechanisms involved in cancer chemoprevention by dietary compounds. Hypericum sps. are widely used in traditional medicine to prepare infusions due to their beneficial digestive and neurologic effects. In this study, we investigated the potential of water extracts from three Hypericum sps. and some of their main phenolic compounds to prevent and repair oxidative and alkylating DNA damage in colon cells. The results showed that water extracts of Hypericum perforatum, Hypericum androsaemum, Hypericum undulatum, quercetin and rutin have protective effect against oxidative DNA damage in HT29 cells. Protective effect was also observed against alkylating DNA damage induced by methyl-methanesulfonate, except for H. androsaemum. With regard to alkylating damage repair H. perforatum, H. androsaemum and chlorogenic acid increased repair of alkylating DNA damage by base excision repair pathway. No effect was observed on nucleotide excision repair pathway. Antigenotoxic effects of Hypericum sps. may contribute to colon cancer prevention and the high amount of phenolic compounds present in Hypericum sps. play an important role in DNA protective effects.


Assuntos
Colo/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Hypericum/química , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Alquilantes/efeitos adversos , Colo/citologia , Dano ao DNA/efeitos dos fármacos , Células HT29/efeitos dos fármacos , Humanos , Testes de Mutagenicidade , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Plantas Medicinais/química , Quercetina/farmacologia , Rutina/farmacologia
12.
J Toxicol Environ Health A ; 75(13-15): 765-75, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22788364

RESUMO

DNA damage induced by oxidative and alkylating agents contributes to carcinogenesis, leading to possible mutations if replication proceeds without proper repair. However, some alkylating agents are used in cancer therapy due to their ability to induce DNA damage and subsequently apoptosis of tumor cells. In this study, the genotoxic effects of oxidative hydrogen peroxide (H2O2) and alkylating agents N-methyl-N-nitrosourea (MNU) and 1,3-bis-(2-chloroethyl)-1-nitosourea (BCNU) agents were examined in two colon cell lines (HCT15 and CO115). DNA damage was assessed by the comet assay with and without lesion-specific repair enzymes. Genotoxic agents were used for induction of DNA damage in both cell lines. Protective effects of extracts of three Salvia species, Salvia officinalis (SO), Salvia fruticosa (SF), and Salvia lavandulifolia (SL), against DNA damage induced by oxidative and alkylating agents were also determined. SO and SF protected against oxidative DNA damage in HCT15 cells. SO and SL decreased DNA damage induced by MNU in CO115 cells. In addition to chemopreventive effects of sage plant extracts, it was also important to know whether these plant extracts may interfere with alkylating agents such as BCNU used in cancer therapy, decreasing their efficacy. Our results showed that sage extracts tested and rosmarinic acid (RA), the main constituent, protected CO115 cells from DNA damage induced by BCNU. In HCT15 cells, only SF induced a reduction in BCNU-induced DNA damage. Sage water extracts and RA did not markedly change DNA repair protein expression in either cell line. Data showed that sage tea protected colon cells against oxidative and alkylating DNA damage and may also interfere with efficacy of alkylating agents used in cancer therapy.


Assuntos
Colo/metabolismo , Dano ao DNA , Mutagênicos/química , Componentes Aéreos da Planta/química , Extratos Vegetais/metabolismo , Substâncias Protetoras/metabolismo , Salvia/química , Alquilantes/antagonistas & inibidores , Alquilantes/toxicidade , Anticarcinógenos/análise , Anticarcinógenos/química , Anticarcinógenos/metabolismo , Anticarcinógenos/farmacologia , Antineoplásicos Alquilantes/antagonistas & inibidores , Antineoplásicos Alquilantes/farmacologia , Bebidas/análise , Carmustina/antagonistas & inibidores , Carmustina/toxicidade , Linhagem Celular , Cinamatos/análise , Cinamatos/farmacologia , Colo/efeitos dos fármacos , Ensaio Cometa , Depsídeos/análise , Depsídeos/farmacologia , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/toxicidade , Metilnitrosoureia/química , Metilnitrosoureia/toxicidade , Mutagênicos/toxicidade , Oxidantes/antagonistas & inibidores , Oxidantes/toxicidade , Extratos Vegetais/química , Portugal , Substâncias Protetoras/análise , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Salvia officinalis/química , Ácido Rosmarínico
13.
Mutat Res ; 692(1-2): 6-11, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20659486

RESUMO

Consumption of fruits and vegetables is associated with a reduced risk of developing a wide range of cancers including colon cancer. In this study, we evaluated the effects of two compounds present in fruits and vegetables, ursolic acid, a triterpenoid, and luteolin, a flavonoid, on DNA protection and DNA repair in Caco-2 cells using the comet assay. Ursolic acid and luteolin showed a protective effect against H(2)O(2)-induced DNA damage. Repair rate (rejoining of strand breaks) after treatment with H(2)O(2) was increased by pre-treatment of Caco-2 cells for 24h with ursolic acid or luteolin. To evaluate effects on induction of base oxidation, we exposed cells to the photosensitizer Ro 19-8022 plus visible light to induce 8-oxoguanine. Luteolin protected against this damage in Caco-2 cells after a short period of incubation. We also measured the incision activity of a cell extract from Caco-2 cells treated for 24h with test compounds, on a DNA substrate containing specific damage (8-oxoGua), to evaluate effects on base excision repair activity. Preincubation for 24h with ursolic acid enhanced incision activity in Caco-2 cells. In conclusion, we demonstrated for the first time that ursolic acid and luteolin not only protect DNA from oxidative damage but also increase repair activity in Caco-2 cells. These effects of ursolic acid and luteolin may contribute to their anti-carcinogenic effects.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Luteolina/farmacologia , Triterpenos/farmacologia , Células CACO-2 , Ensaio Cometa , Humanos , Peróxido de Hidrogênio/farmacologia , Ácido Ursólico
14.
J Agric Food Chem ; 58(12): 7465-71, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20486687

RESUMO

DNA damage can lead to carcinogenesis if replication proceeds without proper repair. This study evaluated the effects of the water extracts of three Salvia sp., Salvia officinalis (SO), Salvia fruticosa (SF), and Salvia lavandulifolia (SL), and of the major phenolic constituents, rosmarinic acid (RA) and luteolin-7-glucoside (L-7-G), on DNA protection in Caco-2 and HeLa cells exposed to oxidative agents and on DNA repair in Caco-2 cells. The comet assay was used to measure DNA damage and repair capacity. The final concentration of each sage extract was 50 microg/mL, and concentrations of RA and L-7-G were 50 and 20 microM, respectively. After a short incubation (2 h), L-7-G protected DNA in Caco-2 cells from damage induced by H(2)O(2) (75 microM); also, after a long incubation (24 h), SF, RA, and L-7-G had protective effects in Caco-2 cells. In HeLa cells, SO, SF, and RA protected against damage induced by H(2)O(2) after 24 h of incubation. Assays of DNA repair show that SO, SF, and L-7-G increased the rate of DNA repair (rejoining of strand breaks) in Caco-2 cells treated with H(2)O(2). The incision activity of a Caco-2 cell extract on a DNA substrate containing specific damage (8-oxoGua) was also measured to evaluate effects on base excision repair (BER) activity. Preincubation for 24 h with SO and L-7-G had a BER inductive effect, increasing incision activity in Caco-2 cells. In conclusion, SO, SF, and the isolated compounds (RA and L-7-G) demonstrated chemopreventive activity by protecting cells against oxidative DNA damage and stimulating DNA repair (SO, SF, and L-7-G).


Assuntos
Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Flavonoides/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Salvia/química , Células CACO-2 , Células HeLa , Humanos , Peróxido de Hidrogênio/farmacologia , Oxirredução/efeitos dos fármacos , Polifenóis
15.
Int J Mol Sci ; 10(9): 3937-3950, 2009 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-19865527

RESUMO

Salvia officinalis (common sage) is a plant with antidiabetic properties. A pilot trial (non-randomized crossover trial) with six healthy female volunteers (aged 40-50) was designed to evaluate the beneficial properties of sage tea consumption on blood glucose regulation, lipid profile and transaminase activity in humans. Effects of sage consumption on erythrocytes' SOD and CAT activities and on Hsp70 expression in lymphocytes were also evaluated. Four weeks sage tea treatment had no effects on plasma glucose. An improvement in lipid profile was observed with lower plasma LDL cholesterol and total cholesterol levels as well as higher plasma HDL cholesterol levels during and two weeks after treatment. Sage tea also increased lymphocyte Hsp70 expression and erythrocyte SOD and CAT activities. No hepatotoxic effects or other adverse effects were observed.


Assuntos
Bebidas , Hipoglicemiantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Salvia officinalis/química , Administração Oral , Adulto , Alanina Transaminase/sangue , Antioxidantes/metabolismo , Aspartato Aminotransferases/sangue , Glicemia , Pressão Sanguínea/efeitos dos fármacos , Catalase/metabolismo , LDL-Colesterol/sangue , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Células Hep G2 , Humanos , Lipídeos/sangue , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Projetos Piloto , Superóxido Dismutase/metabolismo
16.
Sci. med ; 14(3): 261-266, 2004.
Artigo em Português | LILACS | ID: lil-445346

RESUMO

O objetivo deste trabalho é elucidar e orientar ginecologistas, obstetras e cirurgiões-dentistas para a necessidade do acompanhamento odontológico da gestante. O método utilizado como fonte de pesquisa: Medline, Comut, e Bireme. Associada a outros fatores considerados de risco como o fumo , drogas, hipertensão , raça, condição sócioeconômica e idade da gestante, a doença periodontal pode influenciar na indução de parto prematuro e ao nascimento de bebês de baixo peso. O pré-natal odontológico deveria ser recomendado como rotina, fornecendo orientações preventivas e tratamento adequado para o controle das doenças periodontais, evitando riscos para a saúde do bebê.


Assuntos
Humanos , Feminino , Recém-Nascido , Aleitamento Materno , Bem-Estar Materno , Recém-Nascido Prematuro , Recém-Nascido de Baixo Peso , Saúde Bucal
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