RESUMO
Pleurotus sajor-caju (PSC) is an edible mushroom used in food supplements, presenting antitumor properties through induction of cell death pathways. The PSC potential against colorectal cancer was analyzed by exposing HCT116wt cells to different PSC extracts. The PSC n-hexane extract (PSC-hex) showed the highest cytotoxicity effect (IC50 value 0.05â¯mg/mL). The observed cytotoxicity was then associated to apoptosis-promoting and cell cycle-arrest pathways. PSC-hex was able to induce apoptosis related to breakdown of mitochondrial membrane potential and ROS generation. The absence of cytotoxicity in HTC116-p53 and HTC116-Bax cells, alongside with an increase in p53, Bax and Caspase-3 expression, and decrease in Bcl-2 expression, supports that the pro-apoptotic effect is probably induced through a p53 associated pathway. PSC-hex induced cell cycle arrest at G2/M in HCT116wt without cytotoxicity in HTC116-p21â¯cells. These findings suggest that a p21/p53â¯cell cycle regulation pathway is probably disrupted by compounds present on PSC-hex. Identification of the major components was then performed with ergosta-5,7,22-trien-3ß-ol representing 30.6% of total weight. In silico docking studies of ergosta-5,7,22-trien-3ß against Bcl-2 were performed and results show a credible interaction with the Bcl-2 hydrophobic cleft. The results show that PSC-hex can be used as supplementary food for adjuvant therapy in colorectal carcinoma.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/terapia , Suplementos Nutricionais , Pleurotus/química , Antineoplásicos/isolamento & purificação , Caspase 3/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Ergosterol/análogos & derivados , Ergosterol/isolamento & purificação , Ergosterol/farmacologia , Fase G2/efeitos dos fármacos , Células HCT116 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Several studies have shown that a high consumption of vegetables and fruits is consistently associated with a low risk of oxidative stress-induced diseases, which includes some degenerative diseases such as amyotrophic lateral sclerosis, Alzheimer and Parkinson. Therefore, the objective of this study is to verify the effects of conventional and organic grape juice in the modulation of the neurotrophic factor (BDNF) and astrocytic markers protein (S100B) in hippocampus and frontal cortex of Wistar rats. In this study, 24 male Wistar rats were divided into three groups. To the first one, it was given organic purple grape juice; to the second, conventional grape juice, while the last one received only saline. After 30 days, all rats were sacrificed and hippocampus and frontal cortex were dissected. The animals that received organic and conventional grape juice showed, in frontal cortex, an elevated BNDF levels in relation to saline group. However, S100B levels did not change. These results showed that grape juices are able to modulate important marker in brain tissue, and could be an important factor to prevent brain diseases.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/análise , Lobo Frontal/química , Sucos de Frutas e Vegetais , Hipocampo/química , Subunidade beta da Proteína Ligante de Cálcio S100/análise , Vitis/química , Animais , Antioxidantes/farmacologia , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Alimentos Orgânicos , Lobo Frontal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Masculino , Distribuição Aleatória , Ratos Wistar , Valores de Referência , Reprodutibilidade dos Testes , Subunidade beta da Proteína Ligante de Cálcio S100/efeitos dos fármacosRESUMO
ABSTRACT Several studies have shown that a high consumption of vegetables and fruits is consistently associated with a low risk of oxidative stress-induced diseases, which includes some degenerative diseases such as amyotrophic lateral sclerosis, Alzheimer and Parkinson. Therefore, the objective of this study is to verify the effects of conventional and organic grape juice in the modulation of the neurotrophic factor (BDNF) and astrocytic markers protein (S100B) in hippocampus and frontal cortex of Wistar rats. In this study, 24 male Wistar rats were divided into three groups. To the first one, it was given organic purple grape juice; to the second, conventional grape juice, while the last one received only saline. After 30 days, all rats were sacrificed and hippocampus and frontal cortex were dissected. The animals that received organic and conventional grape juice showed, in frontal cortex, an elevated BNDF levels in relation to saline group. However, S100B levels did not change. These results showed that grape juices are able to modulate important marker in brain tissue, and could be an important factor to prevent brain diseases.
Assuntos
Animais , Masculino , Fator Neurotrófico Derivado do Encéfalo/análise , Vitis/química , Subunidade beta da Proteína Ligante de Cálcio S100/análise , Sucos de Frutas e Vegetais , Lobo Frontal/química , Hipocampo/química , Valores de Referência , Distribuição Aleatória , Reprodutibilidade dos Testes , Ratos Wistar , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Alimentos Orgânicos , Subunidade beta da Proteína Ligante de Cálcio S100/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Antioxidantes/farmacologiaRESUMO
Vitis labrusca L. is the main species used for wine and juice production in Brazil. The grapevine leaves can be used both as functional foods and as cheapest sources for the extraction of phenolic compounds. Besides the antioxidant activity, grapevine leaves exhibited significant anti-inflammatory activity. Therefore, the aim of this study was to develop and validate an analytical methodology to determine the metals selenium (96Se), chromium (53Cr), nickel (62Ni), cadmium (111Cd) and lead (206Pb) in 30 samples of grapevine leaf extracts (Vitis labrusca, Bordo cultivar) using inductively coupled plasma mass spectrometry (ICP-MS). To obtain the grapevine leaf extracts the samples were milled, weighed and digested in microwave oven with nitric acid. The method showed linearity, precision, accuracy and limits of quantification and detection acceptable for INMETRO protocol validation of analytical methods. Therefore, the method using ICP-MS was developed and validated to determine metals concentrations in grapevine leaves of Vitis labrusca L. and the proposed method could be applied in routine analytical laboratory.
Assuntos
Metais/análise , Extratos Vegetais/química , Folhas de Planta/química , Vitis/química , Brasil , Cádmio/análise , Cromo/análise , Chumbo/análise , Espectrometria de Massas/métodos , Níquel/análise , Fenóis/isolamento & purificação , Selênio/análiseRESUMO
Parkinson's disease is characterized by the death of dopaminergic neurons, mainly in the substantia nigra, and causes serious locomotor dysfunctions. It is likely that the oxidative damage to cellular biomolecules is among the leading causes of neurodegeneration that occurs in the disease. Selenium is an essential mineral for proper functioning of the brain, and mainly due to its antioxidant activity, it is possible to exert a special role in the prevention and in the nutritional management of Parkinson's disease. Currently, few researchers have investigated the effects of selenium on Parkinson´s disease. However, it is known that very high or very low body levels of selenium can (possibly) contribute to the pathogenesis of Parkinson's disease, because this imbalance results in increased levels of oxidative stress. Therefore, the aim of this work is to review and discuss studies that have addressed these topics and to finally associate the information obtained from them so that these data and associations serve as input to new research.
Assuntos
Estresse Oxidativo , Doença de Parkinson/etiologia , Selênio/fisiologia , Encéfalo/fisiologia , Neurônios Dopaminérgicos/patologia , Humanos , Doença de Parkinson/prevenção & controle , Substância Negra/patologiaRESUMO
OBJECTIVE: Red propolis, an exclusive variety of propolis found in the northeast of Brazil has shown to present antitumour activity, among several other biological properties. This article aimed to help to evaluate the underlying molecular mechanisms of the potential anticancer effects of red propolis on tumour, Hep-2, and non-tumour cells, Hek-293. METHODS: Differentially expressed proteins in human cell lines were identified through label-free quantitative MS-based proteomic platform, and cells were stained with Giemsa to show morphological changes. KEY FINDINGS: A total of 1336 and 773 proteins were identified for Hep-2 and Hek-293, respectively. Among the proteins here identified, 16 were regulated in the Hep-2 cell line and 04 proteins in the Hek-293 line. Over a total of 2000 proteins were identified under MS analysis, and approximately 1% presented differential expression patterns. The GO annotation using Protein Analysis THrough Evolutionary Relationships classification system revealed predominant molecular function of catalytic activity, and among the biological processes, the most prominent was associated to cell metabolism. CONCLUSION: The proteomic profile here presented should help to elucidate further molecular mechanisms involved in inhibition of cancer cell proliferation by red propolis, which remain unclear to date.
Assuntos
Antineoplásicos/farmacologia , Apiterapia , Neoplasias/metabolismo , Própole/farmacologia , Proteoma/metabolismo , Antineoplásicos/uso terapêutico , Brasil , Linhagem Celular Tumoral , Cromatografia Líquida , Células HEK293 , Humanos , Espectrometria de Massas , Neoplasias/tratamento farmacológico , Própole/uso terapêutico , ProteômicaRESUMO
Garcinia mangostana, popularly known as "mangosteen fruit," originates from Southeast Asia and came to Brazil about 80 years ago where it mainly grows in the states of Pará and Bahia. Although mangosteen or its extracts have been used for ages in Asian folk medicine, data on its potential genotoxicity is missing. We, therefore, evaluated genotoxicity/mutagenicity of hydroethanolic mangosteen extract [HEGM, 10 to 640 µg/mL] in established test assays (Comet assay, micronucleus test, and Salmonella/microsome test). In the Comet assay, HEGM-exposed human leukocytes showed no DNA damage. No significant HEGM-induced mutation in TA98 and TA100 strains of Salmonella typhimurium (with or without metabolic activation) was observed and HEGM-exposed human lymphocytes had no increase of micronuclei. However, HEGM suggested exposure concentration-dependent antigenotoxic potential in leukocytes and antioxidant potential in the yeast Saccharomyces cerevisiae. HEGM preloading effectively protected against H2O2-induced DNA damage in leukocytes (Comet assay). Preloading of yeast with HEGM for up to 4 h significantly protected the cells from lethality of chronic H2O2-exposure, as expressed in better survival. Absence of genotoxicity and demonstration of an antigenotoxic and antioxidant potential suggest that HEGM or some substances contained in it may hold promise for pharmaceutical or nutraceutical application.
RESUMO
Salvia officinalis (Lamiaceae) has been used in south of Brazil as a diary homemade, in food condiment and tea-beverage used for the treatment of several disorders. The objective of this study was to characterize chemical compounds in the hydroalcoholic (ExtHS) and aqueous (ExtAS) extract from Salvia officinalis (L.) by gas chromatography-mass spectrometry (GC-MS) and by high-resolution electrospray ionization mass spectrometry (ESI-QTOF MS/MS), evaluate in vitro ability to scavenge the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPHâ¢) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTSâ¢+), catalase (CAT-like) and superoxide dismutase (SOD-like) activity, moreover cytotoxic by MTT assay, alterations on cell morphology by giemsa and apoptotic-induced mechanism for annexin V/propidium iodide. Chemical identification sage extracts revealed the presence of acids and phenolic compounds. In vitro antioxidant analysis for both extracts indicated promising activities. The cytotoxic assays using tumor (Hep-2, HeLa, A-549, HT-29 and A-375) and in non-tumor (HEK-293 and MRC-5), showed selectivity for tumor cell lines. Immunocytochemistry presenting a majority of tumor cells at late stages of the apoptotic process and necrosis. Given the results presented here, Brazilian Salvia officinalis (L.) used as condiment and tea, may protect the body against some disease, in particularly those where oxidative stress is involved, like neurodegenerative disorders, inflammation and cancer.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Salvia officinalis/química , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Imuno-Histoquímica , Estresse Oxidativo/efeitos dos fármacosRESUMO
Oxidative damages in hepatocytes may be caused by epilepsy and/or anticonvulsant drugs. Epilepsy is one of the most common neurological disorders, characterized by recurrent seizures, which may increase the content of reactive oxygen species. Organic and conventional grape juices are rich in polyphenols, compounds with important antioxidant activity. It is hypothesized that organic and conventional purple grape juices may have protective effect against oxidative damage induced by pentylenetetrazole (PTZ) (a standard convulsant drug) in the liver and serum of Wistar rats. Animals (n = 16 in each group) received, by gavage, saline, organic grape juice or conventional grape juice (10 µL/g of body weight) for 17 days. Subsequently, half of the rats in each group received PTZ (60 mg/kg). After 30 minutes, the animals were euthanized by decapitation. Liver and blood samples were isolated to evaluate oxidative parameters (lipid and protein oxidation, nitric oxide metabolite content, antioxidant defenses, and protein sulfhydryl content). The results of this study showed that although organic juice contains higher polyphenol content than conventional juice, both juices conferred protection against lipid and protein oxidative damage and limited the increase in PTZ-induced nitric oxide metabolite content in the liver and serum. In addition, both juices inhibited the PTZ-induced reduction in enzymatic antioxidant defenses (superoxide dismutase and catalase activities) and sulfhydryl protein content in the liver and serum. In summary, both organic and conventional grape juices were able to reduce oxidative damage induced by PTZ in the liver and serum of Wistar rats.
Assuntos
Proteínas Sanguíneas/metabolismo , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pentilenotetrazol/efeitos adversos , Preparações de Plantas/farmacologia , Polifenóis/farmacologia , Vitis/química , Animais , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Bebidas , Catalase/metabolismo , Convulsivantes/efeitos adversos , Alimentos Orgânicos , Frutas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Óxido Nítrico/metabolismo , Preparações de Plantas/química , Polifenóis/análise , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Compostos de Sulfidrila , Superóxido Dismutase/metabolismoRESUMO
Vitamin A (Vit A) is widely suggested to be protective against oxidative stress. However, different studies have been demonstrated the pro-oxidant effects of retinoids in several experimental models. In this work, we used the yeast Saccharomyces cerevisiae as a model organism to study the Vit A effects on superoxide dismutase (SOD)-deficient yeast strains. We report here that Vit A (10, 20 and 40 mg/ml) decreases the survival of exponentially growing yeast cells, especially in strains deficient in CuZnSOD (sod1Delta) and CuZnSOD/MnSOD (sod1Deltasod2Delta). We also observed the protective effect of vitamin E against the Vit A-induced toxicity. Possible adaptation effects induced by sub-lethal oxidative stress were monitored by pre-, co- and post-treatment with the oxidative agent paraquat. The enzymatic activities of catalase (CAT) and glutathione peroxidase (GPx), and the total glutathione content were determined after Vit A treatment. Our results showed that CuZnSOD represents an important defence against Vit A-generated oxidative damage. In SOD-deficient strains, the main defence against Vit A-produced reactive oxygen species (ROS) is GPx. However, the induction of GPx activity is not sufficient to prevent the Vit A-induced cell death in these mutants in exponential phase growth.
Assuntos
Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Superóxido Dismutase/deficiência , Vitamina A/farmacologia , Vitaminas/farmacologia , Catalase/metabolismo , Proteínas Fúngicas/genética , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Superóxido Dismutase/genéticaRESUMO
Oxidative stress is implicated in several human illnesses, including neurological disorders such as Parkinson's and Alzheimer's diseases. Acai is largely consumed in Brazil and contains high levels of antioxidant compounds. This work aims to study the antioxidant activity of acai frozen fruit pulp in the cerebral cortex, hippocampus, and cerebellum of rats treated with the oxidizing agent hydrogen peroxide (H(2)O(2)). Pretreatment of tissue with acai decreased H(2)O(2)-induced damage of both lipids and proteins in all tissues tested. This fruit was also able to reduce the activities of the antioxidant enzymes superoxide dismutase and catalase to basal levels. We observed a negative correlation between the polyphenol content of acai and the levels of lipid (r = -0.689; P Assuntos
Antioxidantes/farmacologia
, Arecaceae/química
, Encéfalo/efeitos dos fármacos
, Flavonoides/farmacologia
, Peroxidação de Lipídeos/efeitos dos fármacos
, Fenóis/farmacologia
, Preparações de Plantas/farmacologia
, Carbonilação Proteica/efeitos dos fármacos
, Animais
, Antioxidantes/análise
, Antioxidantes/metabolismo
, Encéfalo/metabolismo
, Catalase/metabolismo
, Flavonoides/análise
, Frutas
, Peróxido de Hidrogênio
, Estresse Oxidativo/efeitos dos fármacos
, Fenóis/análise
, Preparações de Plantas/química
, Polifenóis
, Proteínas/metabolismo
, Ratos
, Ratos Wistar
, Superóxido Dismutase/metabolismo
RESUMO
There are many studies related to the antioxidant activity of grape products; however, they concern only purple and white grape varieties. Up to now, there are no reports of studies on the Goethe rose grape variety, either on its antioxidant activity or on its phenolic and mineral quantification. Thus, the purpose of this study was to evaluate in vitro and in vivo antioxidant activity, as well as to quantify total phenolic compounds, ascorbic acid, and mineral content, in a Goethe rose grape juice. The results obtained showed that the Goethe rose grape juice is a great polyphenol source, which contains catechin, epicatechin, and procyanidins (B(1), B(2), B(3), and B(4)). Of all metals analyzed, potassium, calcium, magnesium, and iron showed the highest values. We found that this rose grape juice shows an important antioxidant activity in in vitro (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity) and in vivo (using the Saccharomyces cerevisiae yeast cells) assays. The antioxidant activity could be explained by the significant phenolic content and ascorbic acid levels found in the juice. The results showed that rose grape juice is an excellent antioxidant source, which could contribute to the prevention of many diseases related to oxidative stress, such as atherosclerosis and Parkinson's disease.
Assuntos
Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Minerais/análise , Fenóis/análise , Preparações de Plantas/farmacologia , Vitis/química , Antioxidantes/isolamento & purificação , Ácido Ascórbico , Bebidas , Catequina/análise , Sequestradores de Radicais Livres/isolamento & purificação , Peróxido de Hidrogênio/efeitos adversos , Preparações de Plantas/química , Proantocianidinas/análise , Saccharomyces cerevisiaeRESUMO
The antioxidant properties of purple grape juice, organic and conventional, in brain tissues are not well known. In this study our objective was to evaluate the antioxidant activity in substantia nigra and striatum of rats chronically treated with organic or conventional purple grape juice and to correlate the results obtained with the polyphenol content (total polyphenolic content, resveratrol, and anthocyanins [malvidin, delphinidin, peonidin, and cyanidin]). We observed that CCl(4) damage decreased significantly in the grape juice-treated groups when compared with the control group. In the grape juice-treated groups we further observed a decrease of lipid (thiobarbituric acid-reactive substances assay) and protein (carbonyl) peroxidation, as well as a significant antioxidant protection through the increase of enzyme activity. Antioxidant activities were significantly correlated with polyphenol content. These findings demonstrated that both grape juices have potent antioxidant properties and these activities could be at least attributed to the high phenolic content present in these juices.
Assuntos
Antioxidantes/administração & dosagem , Bebidas/análise , Encéfalo/efeitos dos fármacos , Tetracloreto de Carbono/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Vitis/química , Animais , Encéfalo/enzimologia , Química Encefálica/efeitos dos fármacos , Catalase/metabolismo , Corpo Estriado/efeitos dos fármacos , Alimentos Orgânicos , Frutas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Proteínas do Tecido Nervoso/análise , Oxirredução , Ratos , Ratos Wistar , Substância Negra/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
Grape juice is a source of polyphenols, as catechin, anthocyanidins, resveratrol, and others. Some health benefits have been attributed to these compounds (e.g., antioxidant and antitumorigenic properties). In this study, we investigated the possible antioxidant activity of two different grape juices: organic purple grape juice and conventional purple grape juice. The antioxidant activity of both grape juices was evaluated by an animal model of three groups: control and organic and conventional juices. After 30 days, all animals were sacrificed, and blood and liver were collected to evaluate lipid peroxidation level (thiobarbituric acid-reactive substances [TBARS] assay), protein oxidative level (carbonyl assay), and catalase (CAT) and superoxide dismutase (SOD) activities. The group treated with organic grape juice showed the highest SOD and CAT activities in both plasma and liver when compared with the conventional and control groups (P < .05). In plasma, we observed a positive correlation among SOD and CAT activities, resveratrol, and all anthocyanin contents, suggesting that these polyphenols may be, at least in part, responsible for this increased antioxidant defense. The grape juices were capable of reducing carbonyl and lipid peroxidation levels in plasma and liver. However, in plasma, the organic group showed lower carbonyl and TBARS levels when compared to the conventional grape juice group (P < .05). Our findings suggest that the intake of purple grape juice, especially of organic juice, induces a better antioxidant capacity when compared to conventional juice and that this may be an important issue for further investigations in the area of biochemical functional foods.
Assuntos
Antioxidantes/administração & dosagem , Bebidas/análise , Alimentos Orgânicos , Frutas/química , Hepatopatias/prevenção & controle , Vitis/química , Animais , Antocianinas/análise , Antocianinas/sangue , Tetracloreto de Carbono , Catalase/sangue , Catalase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas , Peroxidação de Lipídeos/efeitos dos fármacos , Lipídeos/sangue , Fígado/enzimologia , Fígado/metabolismo , Hepatopatias/metabolismo , Masculino , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
Many studies have focused on the effect of fresh fruits on the risk of developing cancer and other diseases involved with reactive species and free radicals. The intake of frozen fruits has spread widely in the last years, but, until now, their biological activity is not completely known. In this study, 23 samples of frozen fruits were analyzed for their nutritional composition, total polyphenols, total carotenoids, and vitamin C content. Antioxidant, mutagenic, and antimutagenic effects were also evaluated. Antioxidant assays included 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(.)) scavenging activity and determination of superoxide dismutase (SOD)- and catalase (CAT)-like activities. Mutagenic and antimutagenic evaluations were performed in eukaryotic cells of Saccharomyces cerevisiae yeast. Most samples (74%) showed antioxidant activity similar to vitamin C in the DPPH(.) assay, and this activity was positively correlated (r = 0.366; P Assuntos
Antimutagênicos/análise
, Antioxidantes/análise
, Congelamento
, Frutas/química
, Mutagênicos/análise
, Antimutagênicos/farmacologia
, Antioxidantes/farmacologia
, Ácido Ascórbico/análise
, Compostos de Bifenilo
, Carotenoides/análise
, Catalase/análise
, Flavonoides/análise
, Manipulação de Alimentos/métodos
, Testes de Mutagenicidade
, Mutagênicos/farmacologia
, Praguicidas/análise
, Fenóis/análise
, Picratos
, Polifenóis
, Saccharomyces cerevisiae/efeitos dos fármacos
, Saccharomyces cerevisiae/genética
, Superóxido Dismutase/análise
RESUMO
Cashew (Anacardium occidentale) is a medicinal plant native to Brazil and also yields a nutritious fruit juice. Its large pulpy pseudo-fruit, referred to as the cashew apple, contains high concentrations of vitamin C, carotenoids, phenolic compounds and minerals. Natural and processed cashew apple juice (CAJ/cajuina) are amongst the most popular juices in Brazil, especially in the north-east. Both juices have antioxidant potential and suppress mutagenicity of hydrogen peroxide. In the present study we evaluated the inhibitory effects of CAJ/cajuina on Aflatoxin B1(AFB1)-induced mutation, using the Salmonella/microsome assay with the experimental approaches of pre-, co- and post-treatments. Both CAJ/cajuina suppress AFB1-induced mutagenesis in strain TA102 when applied in co- and in post-treatment. Possible mechanisms for anti-mutagenicity in co-treatment are (a) interaction with S9 enzymes, (b) metabolization to non-mutagenic compounds of AFB1 or (c) inactivation of S9 potential. Total suppression of AFB1 mutagenicity was observed in co-treatment with both CAJ and cajuina. Post-treatment anti-mutagenicity of both juices suggests a modulation of activity of error-prone DNA repair. CAJ/cajuina may be considered promising candidates for control of genotoxicity of AFB1 and may thus be considered as health foods with anti-carcinogenic potential. This promising characteristic warrants further evaluation with in vivo studies.
Assuntos
Aflatoxina B1 , Anacardium , Mutagênese , Brasil , Plantas Medicinais , Salmonella typhimuriumRESUMO
In spite of being one of the first vitamins to be discovered, the full range of biological activities of Vitamin A remains incomplete. A growing body of evidence has demonstrated an apparent enhancement of carcinogenesis, induced by dietary retinol. Since DNA damage is a well-recognized inducer of carcinogenesis, the aim of this study was to test the possible genotoxic effect of dietary retinol, using different types of bioassays. Retinol caused an increased recombinogenic activity in Drosophila melanogaster larvae as measured by the SMART test. In mammalian cell cultures, retinol supplementation-induced DNA double-strands breaks (DSB) and single-strands breaks (SSB), cell cycle progression and proliferative focus formation in terminal-differentiated rat Sertoli cells and increased DNA fragmentation in Chinese hamster lung fibroblasts (V79 cells), as measured by the comet assay. Altogether, our results suggest that retinol causes DNA damage and chromosomal rearrangements, which may disturbs key physiological processes and lead to cell cycle progression and preneoplasic transformation of terminal-differentiated mammalian cells.
Assuntos
Transformação Celular Neoplásica/induzido quimicamente , Dano ao DNA/efeitos dos fármacos , Recombinação Genética/efeitos dos fármacos , Vitamina A/toxicidade , Animais , Células Cultivadas , Cricetinae , Cricetulus , Fragmentação do DNA , Reparo do DNA , Suplementos Nutricionais , Drosophila melanogaster/genética , Masculino , Testes de Mutagenicidade , RatosRESUMO
Aqueous extracts of seven species used in Brazilian popular medicine (Achyrocline satureoides, Iodina rhombifolia, Desmodium incanum, Baccharis anomala, Tibouchina asperior, Luehea divaricata, Maytenus ilicifolia) were screened to the presence of mutagenic activity in the Ames test (Salmonella/microsome). Positive results were obtained for A. satureoides, B anomala and L. divaricata with microsomal activation. As shown elsewhere (Vargas et al., 1990) the metabolites of A. satureoides extract also show the capacity to induce prophage and/or SOS response in microscreen phage induction assay and SOS spot chromotest.