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1.
Int J Obes (Lond) ; 46(11): 2006-2012, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35987956

RESUMO

BACKGROUND/OBJECTIVE: There is evidence that metabolic profile changes after Roux-Y gastric bypass (RYGB), especially due to modifications in the gastrointestinal tract. In addition, previous studies have suggested that probiotics can modify the microbiome and produce metabolites important for metabolic health maintenance. In this sense, the aim of this study was to verify the influence of probiotic supplementation on the plasma metabolite profile after RYGB. METHODS: This was a randomized, double-blind, placebo-controlled clinical trial conducted with 31 patients subjected to RYGB surgery, randomized in probiotic group that was supplemented with a probiotic supplement (FloraVantage®) for 3 months after surgery or a placebo group. Plasma metabonomics was performed using nuclear magnetic resonance (NMR) at the preoperative period (T0) and at 45-50 days (T1) and 90-95 days (T2) during the postoperative period/intervention. RESULTS: Reductions in trimethylamine-N-oxide (TMAO) and alanine were observed in both groups, however this reduction was greater in the probiotic group (TMAO 13.82%, p = 0.01 and alanine 14.03%, p = 0.03) at T2. Additionally, ß-hydroxybutyrate (BHB) levels increased 10.77% in the probiotic group (p = 0.03) compared to the placebo group at T2. CONCLUSION: Supplementation with Lactobacillus acidophilus NCFM and Bifidobacterium lactis Bi-07 was able to associate with significant differences in relevant plasma metabolites associated with improved metabolic health.


Assuntos
Derivação Gástrica , Probióticos , Humanos , Ácido 3-Hidroxibutírico , Estudos Prospectivos , Glicemia/metabolismo , Probióticos/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Alanina , Óxidos
2.
Cell Physiol Biochem ; 48(1): 397-408, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30016791

RESUMO

BACKGROUND/AIMS: Compared with non-obese individuals, obese individuals commonly store more vitamin D in adipose tissue. VDR expression in adipose tissue can influence adipogenesis and is therefore a target pathway deserving further study. This study aims to assess the role of 1,25(OH)2D3 in human preadipocyte proliferation and differentiation. METHODS: RTCA, MTT, and trypan blue assays were used to assess the effects of 1,25(OH)2D3 on the viability, proliferation, and adipogenic differentiation of SGBS cells. Cell cycle and apoptosis analyses were performed with flow cytometry, triglycerides were quantified, and RT-qPCR was used to assess gene expression. RESULTS: We confirmed that the SGBS cell model is suitable for studying adipogenesis and demonstrated that the differentiation protocol induces cell maturation, thereby increasing the lipid content of cells independently of treatment. 1,25(OH)2D3 treatment had different effects according to the cell stage, indicating different modes of action driving proliferation and differentiation. In preadipocytes, 1,25(OH)2D3 induced G1 growth arrest at both tested concentrations without altering CDKN1A gene expression. Treatment with 100 nM 1,25(OH)2D3 also decreased MTT absorbance and the lipid concentration. Moreover, increased normalized cell index values and decreased metabolic activity were not induced by proliferation or apoptosis. Exposure to 100 nM 1,25(OH)2D3 induced VDR, CEBPA, and CEBPB expression, even in the preadipocyte stage. During adipogenesis, 1,25(OH)2D3 had limited effects on processes such as VDR and PPARG gene expression, but it upregulated CEBPA expression. CONCLUSIONS: We demonstrated for the first time that 1,25(OH)2D3 induces changes in preadipocytes, including VDR expression and growth arrest, and increases the lipid content in adipocytes treated for 16 days. Preadipocytes are important cells in adipose tissue homeostasis, and understanding the role of 1,25(OH)2D3 in adipogenesis is a crucial step in ensuring adequate vitamin D supplementation, especially for obese individuals.


Assuntos
Adipogenia/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Vitamina D/análogos & derivados , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , PPAR gama/genética , PPAR gama/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Regulação para Cima/efeitos dos fármacos , Vitamina D/farmacologia
3.
Phytother Res ; 31(3): 387-394, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27991703

RESUMO

Harpagophytum procumbens (Hp) has been used as antiinflammatory and analgesic agent for the treatment of rheumatic diseases. The principal active component of Hp is harpagoside (HA). We tested the toxicity of this new therapeutic agent in a hepatic cell line (HepG2/C3A). Hp was found to be cytotoxic, and HA was found to decrease the number of cells in S phase, increase the number of cells in G2/M phase and induce apoptosis. Neither Hp nor HA was genotoxic. The expression of CDK6 and CTP3A4 was reduced by Hp, and both HA and Hp caused a significant reduction of CYP1A2 and CYP3A4 expression. It is possible that the cytotoxicity caused by HA and Hp does not involve transcriptional regulation of the cyclins and CDKs tested but is instead related to the inhibition of metabolism. This is evidenced by the results of an MTT assay and changes in the expression of genes related to drug metabolism, leading to cell death. Indeed, the cells exhibited decreased proliferation upon exposure to Hp and HA. The data show that treatment with either Hp or HA can be cytotoxic, and this should be taken into consideration when balancing the risks and benefits of treatments for rheumatic diseases. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Proliferação de Células/efeitos dos fármacos , Glicosídeos/toxicidade , Inibidores do Crescimento/toxicidade , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Extratos Vegetais/toxicidade , Piranos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/farmacologia , Inibidores do Crescimento/farmacologia , Harpagophytum/química , Células Hep G2 , Humanos , Extratos Vegetais/farmacologia , Piranos/farmacologia , Medição de Risco , Testes de Toxicidade
4.
Hum Cell ; 27(2): 78-84, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24390805

RESUMO

Soybean isoflavonoids have received significant attention due to their potential anticarcinogenic and antiproliferative effects and possible role in many signal transduction pathways. However, their mechanisms of action and their molecular targets remain to be further elucidated. In this paper, we demonstrated that two soybean isoflavones (genistein and daidzein) reduced the proliferation of the human colon adenocarcinoma grade II cell line (HT-29) at concentrations of 25 and 50-100 µM, respectively. We then investigated the effects of genistein and daidzein by RT-PCR on molecules that involved in tumor development and progression by their regulation of cell proliferation. At a concentration of 50 µM genistein, there was suppressed expression of ß-catenin (CTNNBIP1). Neither genistein nor daidzein affected APC (adenomatous polyposis coli) or survivin (BIRC5) expression when cells were treated with concentrations of 10 or 50 µM. These data suggest that the down-regulation of ß-catenin by genistein may constitute an important determinant of the suppression of HT-29 cell growth and may be exploited for the prevention and treatment of colon cancer.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/patologia , Proteína da Polipose Adenomatosa do Colo/genética , Anticarcinógenos/farmacologia , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Expressão Gênica/efeitos dos fármacos , Genisteína/farmacologia , Proteínas Inibidoras de Apoptose/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Isoflavonas/farmacologia , Fitoestrógenos/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Proteína da Polipose Adenomatosa do Colo/metabolismo , Proteína da Polipose Adenomatosa do Colo/fisiologia , Anticarcinógenos/uso terapêutico , Relação Dose-Resposta a Droga , Expressão Gênica/genética , Genisteína/uso terapêutico , Células HT29 , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Inibidoras de Apoptose/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Isoflavonas/uso terapêutico , Fitoestrógenos/uso terapêutico , Fitoterapia , Glycine max , Survivina
5.
Semina cienc. biol. saude ; 33(1): 11-20, jan.-jun. 2012.
Artigo em Português | LILACS | ID: lil-678662

RESUMO

Estudos epidemiológicos mostram que a ingestão de alimentos ricos em isoflavonas (fitoestrógenos), como a soja, confere proteção contra vários tipos de câncer, o que aumenta o interesse científico e popular sobre esses compostos. No presente estudo, os fitoestrógenos de extrato de soja foram testados quanto aos efeitos genotóxicos e modulador de benzo [a] pireno e bleomicina. Dois fitoestrogênios foram avaliados in vitro, o fitoestrógenos “A” foi fornecido pela Embrapa-Soja, Londrina - PR, e o fitoestrógenos “B” foi comprado em uma farmácia de manipulação local. Os métodos utilizados foram o teste do Cometa (genotoxicidade e antigenotoxicidade) e teste do Micronúcleo com Bloqueio Citocinese mutagenicidade) em células de hepatoma de rato (HTC celulares). As isoflavonas foram testadas em três concentrações pré-estabelecidas pelo ensaio de citotoxidade MTT. Ambos os extratos de isoflavonas não mostraram efeitos genotóxicos no ensaio do cometa, mas mostraram indução de micronúcleo. Na avaliação dos fitoestrogênios para um efeito modulador, ambos os extratos fitoestrogênios mostraram efeito antigenotóxico no ensaio do cometa.


Epidemiologic studies show that the intake of foods rich in isoflavones (phytoestrogens), such as soybeans, confers protection against various types of cancer, what increases the scientific and popular interest on these compounds. In the present study, phytoestrogens extracts from soybeans were tested for genotoxic potential and modulatory effects on benzo[a]pyrene and bleomycin. Two phytoestrogens were evaluated in vitro, phytoestrogen “A” was supplied by EMBRAPA-Soja, Londrina – PR, and phytoestrogen “B” was purchased in a local drug store. The methods used were the comet assay (genotoxicity and antigenotoxicity) and micronucleus test with cytokinesis block (mutagenicity) in rat hepatoma cells (HTC cell). The isoflavones were tested at three concentrations pre-established by the MTT cytotoxicity assay. Both isoflavone extracts showed no genotoxic effects in the comet assay, but showed induction of micronucleus. In the evaluation of the phytoestrogens for a modulatory effect, both phytoestrogens extracts showed antigenotoxicity in the comet assay.


Assuntos
Glycine max , Fitoestrógenos , Genotoxicidade , Testes de Mutagenicidade
6.
Mutat Res ; 715(1-2): 7-12, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21763329

RESUMO

Intestinal cancers are correlated with diet. Thus, determining and understanding nutrient-genome interactions is important. The present work assessed the action of the oligoelement selenium on cell proliferation, cytotoxicity, and in situ apoptosis induction and on the expression CASP9, BCL-XL and APC genes in intestinal adenocarcinoma cells (HT29). HT29 cells were cultured and treated with selenium at concentrations of 5, 50 and 500ng/mL with or without the damage-inducing agent doxorubicin. These cells were then evaluated for cytotoxicity (MTT), cell proliferation and in situ apoptosis induction. To evaluate gene expression, only the cells treated with 500ng/mL of selenium were used. RNA was extracted from these cells, and the expressions of CASP9, BCL-XL and APC were analyzed by the RT-PCR method. The GAPDH gene was used as a reference gene. The MTT assay showed that selenium was not cytotoxic at any of the concentrations tested. The cell proliferation assay showed that selenium did not interfere with cell proliferation at the three concentrations tested. In contrast, when the three concentrations were combined with doxorubicin, a significant decrease in the proliferation rate was observed. The apoptosis rate was significantly increased in the selenium (500ng/mL) and doxorubicin group. CASP9 expression was increased and BCL-XL expression decreased in the selenium (500ng/mL) and doxorubicin group. APC was significantly increased in the selenium group alone. These results show that selenium increases apoptosis, especially when it is associated with a damage-inducing agent. Also, selenium has an important role in the expression of the APC gene, which is related to cell cycle regulation.


Assuntos
Adenocarcinoma/genética , Proteína da Polipose Adenomatosa do Colo/genética , Caspase 9/genética , Proliferação de Células/efeitos dos fármacos , Selênio/farmacologia , Proteína bcl-X/genética , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Selenometionina/farmacologia
7.
Regul Toxicol Pharmacol ; 59(3): 412-22, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21295629

RESUMO

The development of various types of cancer results from the interaction among endogenous, environmental and hormonal factors, where the most notable of these factors is diet. The aim of the present study was to determine the antigenotoxic, anticarcinogenic, phagocytic and immunomodulatory activities of Agaricus blazei. The test antigenotoxicity (Comet Assay) and anticarcinogenic (Test of Aberrant Crypt Foci) assess changes in DNA and/or intestinal mucosa that correlate to cancer development. Tests of phagocytosis in the spleen and differential count in blood cells allow the inference of modulation of the immune system as well as to propose a way of eliminating cells with DNA damage. Supplementation with the mushroom was carried out under pre-treatment, simultaneous treatment, post-treatment and pre-treatment+continuous conditions. Statistical analysis demonstrated that the mushroom did not have genotoxic activity but showed antigenotoxic activity. Supplementation caused an increase in the number of monocytes and in phagocytic activity, suggesting that supplementation increases a proliferation of monocytes, consequently increasing phagocytic capacity especially in the groups pre-treatment, simultaneous and pre-treatment+continuous. The data suggest that A. blazei could act as a functional food capable of promoting immunomodulation which can account for the destruction of cells with DNA alterations that correlate with the development of cancer, since this mushroom was demonstrated to have a preventive effect against pre-neoplastic colorectal lesions evaluated by the aberrant crypt foci assay. According to these results and the literature, it is believed that supplementation with A. blazei can be an efficient method for the prevention of cancer as well as possibly being an important coadjuvant treatment in chemotherapy.


Assuntos
Agaricus , Antimutagênicos/farmacologia , Antineoplásicos/farmacologia , Fatores Imunológicos/fisiologia , Fagocitose/efeitos dos fármacos , Fagocitose/fisiologia , Extratos Vegetais/farmacologia , Agaricus/genética , Agaricus/imunologia , Animais , Antimutagênicos/isolamento & purificação , Antimutagênicos/metabolismo , Antineoplásicos/sangue , Antineoplásicos/isolamento & purificação , Ensaio Cometa/métodos , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , Fatores Imunológicos/sangue , Fatores Imunológicos/isolamento & purificação , Masculino , Camundongos , Extratos Vegetais/sangue , Extratos Vegetais/isolamento & purificação
8.
Genet Mol Biol ; 33(3): 542-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21637430

RESUMO

The common everyday use of medicinal plants is an ancient, and still very widespread practice, whereby the need for studies on their possible toxicity and mutagenic properties. The species Coccoloba mollis has been much used in phytotherapy, mainly in cases involving loss of memory and stress. In order to investigate its genotoxic and mutagenic potential, ethanolic extracts from the leaves and roots underwent Salmonella/microsome assaying (TA98 and TA100 strains, with and without exogenous metabolism - S9), besides comet and micronucleus tests in vivo.There was no significant increase in the number of revertants/plate of Salmonella strains in any of the analyzed root-extract concentrations, although the extract itself was extremely toxic to the Salmonella TA98 strain in the tests carried out with S9 (doses varying from 0.005 to 0.5 µg/plate). On the other hand, the leaf-extract induced mutations in the TA98 strain in the absence of S9 in the highest concentration evaluated, although at very low mutagenic potency (0.004 rev/ µg). Furthermore, there was no statistically significant increase in the number of comets and micronuclei, in treatments involving Swiss mice. It was obvious that extracts of Coccoloba mollis, under the described experimental conditions, are not mutagenic.

9.
Genet. mol. biol ; 33(3): 542-548, 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-555819

RESUMO

The common everyday use of medicinal plants is an ancient, and still very widespread practice, whereby the need for studies on their possible toxicity and mutagenic properties. The species Coccoloba mollis has been much used in phytotherapy, mainly in cases involving loss of memory and stress. In order to investigate its genotoxic and mutagenic potential, ethanolic extracts from the leaves and roots underwent Salmonella/microsome assaying (TA98 and TA100 strains, with and without exogenous metabolism - S9), besides comet and micronucleus tests in vivo.There was no significant increase in the number of revertants/plate of Salmonella strains in any of the analyzed root-extract concentrations, although the extract itself was extremely toxic to the Salmonella TA98 strain in the tests carried out with S9 (doses varying from 0.005 to 0.5 µg/plate). On the other hand, the leaf-extract induced mutations in the TA98 strain in the absence of S9 in the highest concentration evaluated, although at very low mutagenic potency (0.004 rev/µg). Furthermore, there was no statistically significant increase in the number of comets and micronuclei, in treatments involving Swiss mice. It was obvious that extracts of Coccoloba mollis, under the described experimental conditions, are not mutagenic.


Assuntos
Animais , Microssomos , Plantas Medicinais , Salmonella , Ensaio Cometa , Testes para Micronúcleos , Testes de Mutagenicidade , Polygonaceae
10.
Environ Toxicol Pharmacol ; 28(1): 120-4, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21783991

RESUMO

This research has evaluated the effects of enteral supplementation of glutamine in clastogens and genotoxic damages caused by the acute administration of cisplatin. For this, it was utilized Swiss mice distributed in eight experimental groups: control, cisplatin, glutamine, in three different doses and the combination of these with cisplatin. The results show that the glutamine was present in neither genotoxic nor mutagenic activity. When in association with glutamine and cisplatin, in simultaneous treatment, it was verified the frequency decreased of micronuclei and comets. The damage reduction percentages to the micronucleus ranged from 95.4 to 91.8% after 24h of administration of these compounds and 76.7 to 56.8% after 48h. In the same time the damage reduction percentages to the comet test ranged from 117.0 to 115.0%. The results suggest that glutamine is capable of preventing genotoxic and mutagenic damage according to the experimental design proposed.

11.
Genet. mol. biol ; 31(1): 122-127, 2008. tab
Artigo em Inglês | LILACS | ID: lil-476161

RESUMO

Functional food investigations have demonstrated the presence of substances that could be beneficial to human health when consumed. However, the toxic effects of some substances contained in foods have been determined. Reported medicinal and nutritive properties have led to the extensive commercialization of the basidiomycete fungi Agaricus blazei Murrill (sensu Heinemann), also known as Agaricus brasiliensis Wasser et al., Agaricus subrufescens Peck or the Brazilian medical mushroom (BMM). Different methanolic extract fractions (ME) of this mushroom were submitted to the cytokinesis-block micronucleus (CBMN) clastogenic assay and the hypoxanthine-guanine phosphoribosyl transferase locus (HGPRT) assay for gene mutation, both using Chinese hamster ovary cells clone K1 (CHO-K1). The results suggest that all the fractions tested possess cytotoxic and mutagenic potential but no clastogenic effects. Further information is needed on the biochemical components of the A. blazei methanol fractions to identify any substances with cytotoxic and/or mutagenicity potential. These findings indicate that A. blazei methanolic extract should not be used due to their genotoxicity and care should be taken in the use of A. blazei by the general population until further biochemical characterization of this fungi is completed.


Assuntos
Animais , Agaricus , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Fungos/genética , Testes para Micronúcleos
12.
Toxicol In Vitro ; 20(7): 1225-33, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16716562

RESUMO

Due to the need to identify new antimutagenic agents and to determine their mechanism of action, the present study examined the mechanism of action of the beta-glucan with regard to antimutagenicity using the micronucleus assay in CHO-k1 and HTC cell lines. The mutagenicity experiments were performed with three different concentrations of beta-glucan (5, 10, and 20 microg/mL), in wich only the highest dose showed mutagenic activity. In the antimutagenicity experiments, the same concentrations of beta-glucan were combined with a mutagenic agent, methylmethane sulfonate, or 2-aminoanthracene, using four different treatment protocols: pre-treatment, simultaneous treatment (simple and with pre-incubation), and post-treatment. The results indicate that the CHO-k1 cell line treated with MMS presented a chemopreventive activity for all the doses of beta-glucan in the different treatment protocols, except for the lowest dose in post-treatment. When HTC cell line treated with MMS is analysed, a chemopreventive activity can be verified for the highest dose in both pre- and post-treatment. For the simple simultaneous treatment, the three doses demonstrated efficacy, while for the simultaneous treatment with pre-incubation only the intermediate concentration was effective. In HTC treated with 2AA both the lowest dose in the pre-treatment protocol and the post-treatment protocol did not show efficacy in preventing DNA damage. The evaluation of the different protocols and the damage decrease percentages observed suggest that beta-glucan has both desmutagenic and bioantimutagenic activity. It is necessary, however, to note that efficacy and mechanism of action are subject to variation when compared the two cell lines, since in HTC, representing a drug-metabolizing system, this substance can show a diminished chemopreventive capacity.


Assuntos
Antimutagênicos/farmacologia , Hordeum/química , Testes para Micronúcleos/métodos , beta-Glucanas/farmacologia , Animais , Antracenos/toxicidade , Antimutagênicos/química , Antimutagênicos/isolamento & purificação , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Metanossulfonato de Metila/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Mutagênicos/toxicidade , beta-Glucanas/química , beta-Glucanas/isolamento & purificação
13.
Semina cienc. biol. saude ; 26(2): 131-140, out.-dez. 2005. tab
Artigo em Português | LILACS | ID: lil-429356

RESUMO

O Agaricus blazei Murril ss. Heinemann (ABM), cogumelo comestível nativo do Brasil, tem sido utilizado na medicina popular no tratamento de inúmeras doenças, incluindo o câncer. O objetivo do presente estudo foi avaliar os efeitos do extrato ABM (0,4 por cento) na clastogenicidade induzida pela exposição à radiação ultravioleta (UV), em células CHO-k1, pelo teste de aberração cromossômica. As células foram tratadas em diferentes condições (tratamento contínuo, pré-tratamento e pós-tratamento), associadas à indução de danos no DNA pela UV. A análise dos dados demonstrou que a UV e o ABM apresentaram atividade clastogênica. Nos protocolos de pré e pós-tratamento não foram evidenciados efeitos anticlastogênicos. No entanto, o protocolo de tratamento contínuo demonstrou efeito protetor com redução de danos de 86,1 por cento. Os resultados não permitem inferir com clareza o tipo de mecanismo de ação do extrato de ABM, o qual poderia agir tanto por desmutagênese, quanto por bioantimutagênese. no entanto, é evidente o seu efeito na diminuição de danos causados por radiação não-ionizante, apesar de, em concentração muito elevada, apresentar atividade clastogênica.


Assuntos
Radiação não Ionizante , Protetores Solares , Raios Ultravioleta , Agaricus , Luz , Mutação
14.
Cancer Sci ; 94(2): 188-92, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12708495

RESUMO

The modifying potential of crude extracts of the mushroom Agaricus blazei Murrill (Himematsutake) on the development and growth of glutathione S-transferase placental form (GST-P)-positive liver foci (liver preneoplastic lesion) was investigated in adult male Wistar rats. Six groups of animals were used. Groups 2 to 5 were given a single i.p. injection of 200 mg/kg b.w. of diethylnitrosamine (DEN) and groups 1 and 6 were treated with saline at the beginning of the experiment. After 2 weeks, animals of groups 3 to 6 were orally treated with three dose levels of aqueous extracts of the mushroom A. blazei (1.2, 5.6, 11.5, and 11.5 mg/ml of dry weight of solids) for 6 weeks. All animals were subjected to two-thirds partial hepatectomy at week 3 and sacrificed at week 8. Two hours before sacrifice, ten animals of each group were administered a single i.p injection of 100 mg/kg of bromodeoxyuridine (BrdU). Apoptotic bodies and BrdU-positive hepatocyte nuclei were quantified in liver sections stained for hematoxylin and eosin (H&E) (eosinophilic foci) and simultaneously stained for GST-P expression (GST-P-positive foci), respectively. The 6-week treatment with A. blazei did not alter the development (number and size) of GST-P-positive foci and did not affect the growth kinetics of liver normal parenchyma or foci in DEN-initiated animals. Our results indicate that the treatment with aqueous extracts of the mushroom A. blazei during the post-initiation stage of rat liver carcinogenesis does not exert any protective effect against the development of GST-P-positive foci induced by DEN.


Assuntos
Agaricus/química , Anticarcinógenos/uso terapêutico , Hepatopatias/prevenção & controle , Neoplasias Hepáticas Experimentais/prevenção & controle , Fitoterapia , Extratos Vegetais/uso terapêutico , Lesões Pré-Cancerosas/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/análise , Brasil , Bromodesoxiuridina , Divisão Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas , Replicação do DNA/efeitos dos fármacos , Dietilnitrosamina , Ensaios de Seleção de Medicamentos Antitumorais , Glutationa Transferase/análise , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Hepatócitos/patologia , Hepatopatias/enzimologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/enzimologia , Masculino , Medicina Tradicional , Proteínas de Neoplasias/análise , Tamanho do Órgão/efeitos dos fármacos , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/enzimologia , Ratos , Ratos Wistar , Água
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