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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.
Molecules ; 26(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299562

RESUMO

Fucoxanthin (Fx) is a carotenoid derived from marine organisms that exhibits anticancer activities. However, its role as a potential drug adjuvant in breast cancer (BC) treatment is still poorly explored. Firstly, this study investigated the cytotoxic effects of Fx alone and combined with doxorubicin (Dox) and cisplatin (Cis) on a panel of 2D-cultured BC cell lines (MCF7, SKBR3 and MDA-MB-231) and one non-tumoral cell line (MCF12A). Fucoxanthin induced cytotoxicity against all the cell lines and potentiated Dox cytotoxic effects towards the SKBR3 and MDA-MB-231 cells. The combination triggering the highest cytotoxicity (Fx 10 µM + Dox 1 µM in MDA-MB-231) additionally showed significant induction of cell death and genotoxic effects, relative to control. In sequence, the same combination was tested on 3D cultures using a multi-endpoint approach involving bioactivity assays and microscopy techniques. Similar to 2D cultures, the combination of Fx and Dox showed higher cytotoxic effects on 3D cultures compared to the isolated compounds. Furthermore, this combination increased the number of apoptotic cells, decreased cell proliferation, and caused structural and ultrastructural damages on the 3D models. Overall, our findings suggest Fx has potential to become an adjuvant for Dox chemotherapy regimens in BC treatment.


Assuntos
Adjuvantes Farmacêuticos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Xantofilas/farmacologia , Técnicas de Cultura de Células , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos
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.
Am J Orthod Dentofacial Orthop ; 158(5): 722-730.e16, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33008707

RESUMO

INTRODUCTION: This study aimed to determine whether single nucleotide polymorphisms in the growth hormone receptor (GHR) and insulin-like growth factor 2 receptor (IGF2R) genes are associated with different craniofacial phenotypes. METHODS: A total of 596 orthodontic and 98 orthognathic patients from 4 cities in Brazil were included for analyses. Angular and linear cephalometric measurements were obtained, and phenotype characterizations were performed. Genomic DNA was collected from buccal cells and single nucleotide polymorphisms in GHR (rs2910875, rs2973015, rs1509460) and IGF2R (rs2277071, rs6909681, rs6920141) were genotyped by polymerase chain reactions using TaqMan assay. Genotype-phenotype associations were assessed in the total sample (statistical significance was set at P <8.333 × 10-3) and by a meta-analytic approach implemented to calculate the single effect size measurement for the different cohorts. RESULTS: Rare homozygotes for the GHR rs2973015 showed increased measurements for the lower anterior facial height (ANS-Me) and mandibular sagittal lengths (Co-Gn and Go-Pg). In contrast, common homozygotes for the IGF2R rs6920141 presented reduced measurements for these dimensions (ANS-Me and Go-Pg). Furthermore, the less common homozygotes for IGF2R rs2277071 had reduced maxillary sagittal length (Ptm'-A'). The meta-analytical approach replicated the associations of rs2973015 with ANS-Me, rs2277071 with Ptm'-A', and rs6920141 with Go-Pg. CONCLUSIONS: Our results provide further evidence that GHR contributes to the determination of mandibular morphology. In addition, we report that IGF2R is a possible gene associated with variations in craniofacial dimensions. Applying meta-analytical approaches to genetic variation data originating from likely underpowered samples may provide additional insight regarding genotype and/or phenotype associations.


Assuntos
Proteínas de Transporte , Mucosa Bucal , Receptor IGF Tipo 2 , Receptores da Somatotropina , Brasil , Proteínas de Transporte/genética , Cefalometria , Humanos , Mandíbula , Polimorfismo de Nucleotídeo Único/genética , Receptor IGF Tipo 2/genética , Receptores da Somatotropina/genética
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 ; 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
7.
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
8.
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
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.
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
11.
Toxics ; 10(8)2022 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-35893848

RESUMO

Three-dimensional cell cultures may better mimic avascular tumors. Yet, they still lack characterization and standardization. Therefore, this study aimed to (a) generate multicellular aggregates (MCAs) of four breast cell lines: MCF7, MDA-MB-231, and SKBR3 (tumoral) and MCF12A (non-tumoral) using ultra-low attachment (ULA) plates, (b) detail the methodology used for their formation and analysis, providing technical tips, and (c) characterize the MCAs using morphometry, qualitative cytology (at light and electron microscopy), and quantitative immunocytochemistry (ICC) analysis. Each cell line generated uniform MCAs with structural differences among cell lines: MCF7 and MDA-MB-231 MCAs showed an ellipsoid/discoid shape and compact structure, while MCF12A and SKBR3 MCAs were loose, more flattened, and presented bigger areas. MCF7 MCAs revealed glandular breast differentiation features. ICC showed a random distribution of the proliferating and apoptotic cells throughout the MCAs, not fitting in the traditional spheroid model. ICC for cytokeratin, vimentin, and E-cadherin showed different results according to the cell lines. Estrogen (ER) and progesterone (PR) receptors were positive only in MCF7 and human epidermal growth factor receptor 2 (HER-2) in SKBR3. The presented characterization of the MCAs in non-exposed conditions provided a good baseline to evaluate the cytotoxic effects of potential anticancer compounds.

12.
Environ Pollut ; 293: 118467, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34748885

RESUMO

Genotoxic effects of dicofol on the edible clam Meretrix meretrix were investigated through a mesocosm experiment. Individuals of M. meretrix, were exposed to environmental concentration (D1 = 50 ng/L) and supra-environmental concentration (D2 = 500 ng/L) of dicofol for 15 days, followed by the same depuration period. DNA damage (i.e., strand breaks and alkali-labile sites) was evaluated at day 1, 7 and 15, during uptake and depuration, using Comet assay (alkaline version) and nuclear abnormalities (NAs) as genotoxicity biomarkers. The protective effects of dicofol against DNA damage induced by ex vivo hydrogen peroxide (H2O2) exposure were also assessed. Comet assay results revealed no significant DNA damages under dicofol exposure, indicating 1) apparent lack of genotoxicity of dicofol to the tested conditions and/or 2) resistance of the animals due to optimal adaptation to stress conditions. Moreover, ex vivo H2O2 exposure showed an increase in the DNA damage in all the treatments without significant differences between them. However, considering only the DNA damage induced by H2O2 during uptake phase, D1 animals had significantly lower DNA damage than those from other treatments, revealing higher protection against a second stressor. NAs data showed a decrease in the % of cells with polymorphic, kidney shape, notched or lobbed nucleus, along the experiment. The combination of these results supports the idea that the clams used in the experiment were probably collected from a stressful environment (in this case Pearl River Delta region) which could have triggered some degree of adaptation to those environmental conditions, explaining the lack of DNA damages and highlighting the importance of organisms' origin and the conditions that they were exposed during their lives.


Assuntos
Bivalves , Dano ao DNA , Dicofol , Animais , Bivalves/efeitos dos fármacos , Bivalves/genética , Ensaio Cometa , Dicofol/toxicidade , Peróxido de Hidrogênio/toxicidade
13.
Braz J Otorhinolaryngol ; 88 Suppl 1: S91-S96, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34016567

RESUMO

INTRODUCTION: Vestibular recruitment is a sign of hyperexcitability of central vestibular neurons and may be characteristic of peripheral vestibular damage. OBJECTIVE: To define the post-caloric recruitment index and its ability to predict the stage of vestibular compensation and peripheral lesion. METHODS: First of all, we demonstrated that larger values in the cold post-caloric stimulation compared to warm stimulation were equivalent to vestibular recruitment observed during the sinusoidal harmonic acceleration test. In the next step, patients with vestibular complaints and asymptomatic controls were submitted to the caloric test. We calculated post-caloric recruitment index for the control group. Among the study group, we analyzed the relation between post-caloric recruitment and unilateral weakness as well as the types of vestibular diagnoses. RESULTS: Mean post-caloric recruitment was 17.06% and 33.37% among the control and study group, respectively. The ratio between post-caloric recruitment and unilateral weakness was 1.3 in the study group. Among recruiting subjects, no significant difference of unilateral weakness from the lesioned or healthy side was observed. We found no differences in vestibular diagnoses between recruiting and non-recruiting subjects. CONCLUSION: Post-caloric recruitment index identified asymmetric vestibular tonus and central compensation. The normal value was established at 17.06%.


Assuntos
Neurônios , Nervo Vestibular , Humanos , Nervo Vestibular/fisiologia , Neurônios/fisiologia
14.
Toxics ; 9(2)2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33572635

RESUMO

Seaweed bioactive compounds have shown anticancer activities in in vitro and in vivo studies. However, tests remain limited, with conflicting results, and effects in combination with anticancer drugs are even scarcer. Here, the cytotoxic effects of five seaweed compounds (astaxanthin, fucoidan, fucosterol, laminarin, and phloroglucinol) were tested alone and in combination with anticancer drugs (cisplatin-Cis; and doxorubicin-Dox), in breast cell lines (three breast cancer (BC) subtypes and one non-tumoral). The combinations revealed situations where seaweed compounds presented potentiation or inhibition of the drugs' cytotoxicity, without a specific pattern, varying according to the cell line, concentration used for the combination, and drug. Fucosterol was the most promising compound, since: (i) it alone had the highest cytotoxicity at low concentrations against the BC lines without affecting the non-tumoral line; and (ii) in combination (at non-cytotoxic concentration), it potentiated Dox cytotoxicity in the triple-negative BC cell line. Using a comparative approach, monolayer versus 3D cultures, further investigation assessed effects on cell viability and proliferation, morphology, and immunocytochemistry targets. The cytotoxic and antiproliferative effects in monolayer were not observed in 3D, corroborating that cells in 3D culture are more resistant to treatments, and reinforcing the use of more complex models for drug screening and a multi-approach that should include histological and ICC analysis.

15.
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
17.
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
18.
Prog Orthod ; 21(1): 9, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32249341

RESUMO

BACKGROUND: The aim of the present study was to assess if genetic polymorphisms in tooth agenesis (TA)-related genes are associated with craniofacial morphological patterns. METHODS: This cross-sectional, multi-center, genetic study evaluated 594 orthodontic Brazilians patients. The presence or absence of TA was determined by analysis of panoramic radiography. The patients were classified according to their skeletal malocclusion and facial growth pattern by means of digital cephalometric analysis. Genomic DNA was extracted from squamous epithelial cells of buccal mucosa and genetic polymorphisms in MSX1 (rs1042484), PAX9 (rs8004560), TGF-α (rs2902345), FGF3 (rs1893047), FGF10 (rs900379), and FGF13 (rs12838463, rs5931572, and rs5974804) were genotyped by polymerase chain reaction using TaqMan chemistry and end-point analysis. RESULTS: Genotypes (p = 0.038) and allele (p = 0.037) distributions for the FGF3 rs1893047 were significantly different according to the skeletal malocclusion. Carrying at least one G allele increased in more than two times the chance of presenting skeletal class III malocclusion (OR = 2.21, CI 95% = 1.14-4.32; p = 0.017). There was no association between another skeletal craniofacial pattern and some polymorphism assessed in the present study. CONCLUSION: Our results suggest that the genetic polymorphism rs1893047 in FGF3 might contribute to variations in the craniofacial sagittal pattern.


Assuntos
Anodontia , Má Oclusão , Brasil , Cefalometria , Estudos Transversais , Genótipo , Humanos
19.
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
20.
Arch Oral Biol ; 103: 12-18, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31112935

RESUMO

OBJECTIVE: The present cross-sectional, multi-centre, genetic study aimed to determine, whether single nucleotide polymorphisms (SNPs) in tooth agenesis (TA)-associated GLI2 and GLI3 genes contribute to the development of craniofacial skeletal morphology in humans. DESIGN: Orthodontic patients from an ethnically heterogeneous population were selected for the present study (n = 594). The presence or absence of TA was determined by analysis of panoramic radiography and dental records. The subjects were classified according to their skeletal malocclusion and facial growth pattern by means of digital cephalometric analysis. Genomic DNA was extracted from squamous epithelial cells of the buccal mucosa and SNPs in GLI2 (rs3738880, rs2278741) and GLI3 (rs929387, rs846266) were analysed by polymerase chain reaction using TaqMan chemistry and end-point analysis. RESULTS: Class II skeletal malocclusion presented a significantly lower frequency of TA (P < 0.05). Subjects without TA showed significantly higher ANB angles (P < 0.05). Genotype and/or allele distributions of the SNPs in GLI2 (rs3738880, rs2278741) and GLI3 (rs846266) were associated with the presence of TA (P < 0.05). The SNPs rs3738880, rs2278741 and rs929387 were also associated with some type of skeletal malocclusion (P < 0.05), but not with the facial growth pattern (P > 0.05). The G allele for TA-related GLI2 rs3738880 was strongly linked to the presence of Class III skeletal malocclusion (OR = 2.03; 95% CI = 1.37-3.03; P<3125 × 10-6). GLI2 rs2278741 C allele was overrepresented in individuals without TA, suggesting it as a protective factor for this dental phenotype (OR = 0.43; 95% CI = 0.24-0.78; P<625 × 10-5). CONCLUSION: The present study suggests that SNPs in TA-associated GLI2 and GLI3 genes may also play a role in the development of skeletal malocclusions. rs3738880 and rs2278741 in GLI2 seems to contribute to the genetic background for skeletal Class III and TA, respectively. TA could be an additional predictor of craniofacial morphology in some cases. Further research replicating the reported associations should be performed.


Assuntos
Anormalidades Craniofaciais/genética , Má Oclusão/genética , Proteínas do Tecido Nervoso/genética , Proteínas Nucleares/genética , Proteína Gli2 com Dedos de Zinco/genética , Proteína Gli3 com Dedos de Zinco/genética , Cefalometria , Anormalidades Craniofaciais/etiologia , Estudos Transversais , Genótipo , Humanos , Má Oclusão/etiologia , Fenótipo , Polimorfismo de Nucleotídeo Único
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