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1.
Toxicol Appl Pharmacol ; 280(3): 421-33, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25173957

RESUMO

Cell differentiation and response to hormonal signals were studied in a 3D environment on an in-house generated mouse fibroblast cell line expressing a reporter gene under the control of estrogen responsive sequences (EREs). 3D cell culture conditions were obtained in a Rotary Cell Culture System; (RCCS™), a microgravity based bioreactor that promotes the aggregation of cells into multicellular spheroids (MCS). In this bioreactor the cells maintained a better differentiated phenotype and more closely resembled in vivo tissue. The RCCS™ cultured fibroblasts showed higher expression of genes regulating cell assembly, differentiation and hormonal functions. Microarray analysis showed that genes related to cell cycle, proliferation, cytoskeleton, migration, adhesion and motility were all down-regulated in 3D as compared to 2D conditions, as well as oncogene expression and inflammatory cytokines. Controlled remodeling of ECM, which is an essential aspect of cell organization, homeostasis and tissue was affected by the culture method as assessed by immunolocalization of ß-tubulin. Markers of cell organization, homeostasis and tissue repair, metalloproteinase 2 (MMP2) and its physiological inhibitor (TIMP4) changed expression in association with the relative formation of cell aggregates. The fibroblasts cultured in the RCCS™ maintain a better responsiveness to estrogens, measured as expression of ERα and regulation of an ERE-dependent reporter and of the endogenous target genes CBP, Rarb, MMP1 and Dbp. Our data highlight the interest of this 3D culture model for its potential application in the field of cell response to hormonal signals and the pharmaco-toxicological analyses of chemicals and natural molecules endowed of estrogenic potential.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Estrogênios/fisiologia , Matriz Extracelular/fisiologia , Fibroblastos/fisiologia , Animais , Perfilação da Expressão Gênica , Camundongos , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , RNA/química , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
2.
Toxicol Sci ; 97(2): 299-307, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17337754

RESUMO

Isoflavones are important dietary compounds that are consumed with the daily diet and elicit important biological actions. Here we report on the ability of genistein to partially accumulate in body depots of male mice, be released following fasting, and modulate the actions of estradiol and environmental estrogens in reproductive and nonreproductive target organs of estrogen-reporter mice (ERE-tK-luciferase). After the consumption of 50 mg/kg/day for 3 days, genistein accumulates in body compartments where it remains at functionally active levels for at least 15 days. Following 48 h of fasting, its concentration increased in serum from 99 +/- 13 to 163 +/- 17 nM. These levels are sufficient to exert an estrogenic effect in the testis and liver, as revealed by a twofold increase in luciferase gene expression. beta-Benzene-hexachloride (betaBHC) given at the concentration of 100 mg/kg/day for 3 days also accumulates in the body and is released by fasting, reaching serum levels of 176 +/- 33 nM, upregulating the luciferase gene in the liver and inhibiting its expression in the testis. When genistein was given in combination with betaBHC at doses sufficient to induce accumulation of both in body depots, the genistein mobilized by fasting reversed the action of the mobilized betaBHC in the testis. Acute administration of nutritional doses of genistein inhibited the action of estradiol and reversed the antiestrogenic action of o,p'-DDT: 1,1,1,-trichloro-2(p-chlorophenyl)-2-(o-chlorophenyl)ethane in the liver and the antiestrogenic action of betaBHC in the testis. Genistein had an additive effect with the ER agonist p,p'-DDT: 1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane in the liver. The observed effects may be relevant to a protective action of phytoestrogens against estrogen receptor-interacting pollutants as well as the dietary modulation of estradiol action.


Assuntos
Anticarcinógenos/farmacocinética , Estradiol/farmacologia , Antagonistas de Estrogênios , Estrogênios não Esteroides/farmacologia , Estrogênios não Esteroides/farmacocinética , Jejum/metabolismo , Genisteína/farmacologia , Genisteína/farmacocinética , Hidrocarbonetos Clorados/antagonistas & inibidores , Hidrocarbonetos Clorados/farmacologia , Fitoestrógenos/farmacologia , Fitoestrógenos/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão , Estrogênios não Esteroides/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Genisteína/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Luciferases/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Fitoestrógenos/sangue , Receptores de Estrogênio/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/metabolismo
3.
BMC Complement Altern Med ; 7: 19, 2007 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-17559639

RESUMO

BACKGROUND: Maharishi Amrit Kalash (MAK) is an herbal formulation composed of two herbal mixtures, MAK-4 and MAK-5. These preparations are part of a natural health care system from India, known as Maharishi Ayur-Veda. MAK-4 and MAK-5 are each composed of different herbs and are said to have maximum benefit when used in combination. This investigation evaluated the cancer inhibiting effects of MAK-4 and MAK-5, in vitro and in vivo. METHODS: In vitro assays: Aqueous extracts of MAK-4 and MAK-5 were tested for effects on ras induced cell transformation in the Rat 6 cell line assessed by focus formation assay. In vivo assays: Urethane-treated mice were put on a standard pellet diet or a diet supplemented with MAK-4, MAK-5 or both. At 36 weeks, livers were examined for tumors, sera for oxygen radical absorbance capacity (ORAC), and liver homogenates for enzyme activities of glutathione peroxidase (GPX), glutathione-S-transferase (GST), and NAD(P)H: quinone reductase (QR). Liver fragments of MAK-fed mice were analyzed for connexin (cx) protein expression. RESULTS: MAK-5 and a combination of MAK-5 plus MAK-4, inhibited ras-induced cell transformation. In MAK-4, MAK-5 and MAK4+5-treated mice we observed a 35%, 27% and 46% reduction in the development of urethane-induced liver nodules respectively. MAK-4 and MAK4+5-treated mice had a significantly higher ORAC value (P < 0.05) compared to controls (200.2 +/- 33.7 and 191.6 +/- 32.2 vs. 152.2 +/- 15.7 ORAC units, respectively). The urethane-treated MAK-4, MAK-5 and MAK4+5-fed mice had significantly higher activities of liver cytosolic enzymes compared to the urethane-treated controls and to untreated mice: GPX(0.23 +/- 0.08, 0.21 +/- 0.05, 0.25 +/- 0.04, 0.20 +/- 0.05, 0.21 +/- 0.03 U/mg protein, respectively), GST (2.0 +/- 0.4, 2.0 +/- 0.6, 2.1 +/- 0.3, 1.7 +/- 0.2, 1.7 +/- 0.2 U/mg protein, respectively) and QR (0.13 +/- 0.02, 0.12 +/- 0.06, 0.15 +/- 0.03, 0.1 +/- 0.04, 0.11 +/- 0.03 U/mg protein, respectively). Livers of MAK-treated mice showed a time-dependent increased expression of cx32. CONCLUSION: Our results show that a MAK-supplemented diet inhibits liver carcinogenesis in urethane-treated mice. The prevention of excessive oxidative damage and the up-regulation of connexin expression are two of the possible effects of these products.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/metabolismo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Ayurveda , Preparações de Plantas/farmacologia , Animais , Modelos Animais de Doenças , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Técnicas In Vitro , Camundongos , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Oxirredução , Quinona Redutases/metabolismo , Ratos , Uretana
4.
Water Res ; 45(8): 2473-84, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21420711

RESUMO

A major source of the wide presence of EDCs (Endocrine Disrupting Compounds) in water bodies is represented by direct/indirect discharge of sewage. Recent scientific literature reports data about their trace concentration in water, sediments and aquatic organisms, as well as removal efficiencies of different wastewater treatment schemes. Despite the availability of a huge amount of data, some doubts still persist due to the difficulty in evaluating synergistic effects of trace pollutants in complex matrices. In this paper, an integrated assessment procedure was used, based on chemical and biological analyses, in order to compare the performance of two full scale biological wastewater treatment plants (either equipped with conventional settling tanks or with an ultrafiltration membrane unit) and tertiary ozonation (pilot scale). Nonylphenol and bisphenol A were chosen as model EDCs, together with the parent compounds mono- and di-ethoxylated nonylphenol (quantified by means of GC-MS). Water estrogenic activity was evaluated by applying the human breast cancer MCF-7 based reporter gene assay. Process parameters (e.g., sludge age, temperature) and conventional pollutants (e.g., COD, suspended solids) were also measured during monitoring campaigns. Conventional activated sludge achieved satisfactory removal of both analytes and estrogenicity. A further reduction of biological activity was exerted by MBR (Membrane Biological Reactor) as well as ozonation; the latter contributed also to decrease EDC concentrations.


Assuntos
Disruptores Endócrinos/química , Fenóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Compostos Benzidrílicos , Reatores Biológicos , Linhagem Celular Tumoral , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Humanos , Oxirredução , Ozônio/química , Fenóis/análise , Fenóis/metabolismo , Fenóis/toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
5.
Toxicol Sci ; 103(1): 57-67, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18281260

RESUMO

The widespread use of diets containing estrogenic compounds raises questions on how relevant the presence of phytoestrogens may be, in order to allow a correct development of the reproductive ability and sexual maturity in humans and animals. The isoflavone genistein is the most estrogenically active molecule present in soy. Here we show that genistein, through an estrogen receptor (ER)-mediated action, modulates gene expression in the whole body of male mice in a dose- and time-dependent manner, at all ages. By luciferase bioassays, we show that genistein-induced ER activation is present in reproductive and nonreproductive organs of the transgenic mice Estrogen Responsive Element (ERE)-tK-LUC, although to an extent that is lower than what observed with the administration of estradiol. Peak activity was registered at genistein doses of 500-5000 microg/kg, at 12 h from the administration by gavage. In the liver, ER-alpha and ER-beta messenger RNAs and two target genes, CYP17 and the progesterone receptor, were modulated by genistein. CYP17 and PR time-dependent induction was similar to that of luciferase. ER-alpha protein level followed an opposite regulation by genistein and estradiol. Genistein passed from the lactating mother to the suckling offspring at levels sufficient to activate gene expression in reproductive and nonreproductive tissues of the pups, with maximal upregulation at 16-24 h. We also followed responsiveness to genistein in the testis, from early development to adult age. Testis are well responsive to genistein as well as to estradiol already at day 14.5 of fetal development, as determined by exposing organotypic cultures from mouse fetus testis. Ovaries were not responsive under the same conditions. Activation of luciferase correlates with an activation of cell proliferation in testis, but not in the ovaries. Prolonged exposure (15 days) to genistein also decreases prostate weight like estradiol. In conclusion, our results show that genistein affects reproductive and nonreproductive organs of male mice in a dose- and time-dependent manner, at all developmental ages.


Assuntos
Genisteína/farmacologia , Animais , Feminino , Gônadas/efeitos dos fármacos , Gônadas/embriologia , Gônadas/fisiologia , Lactação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Mensageiro/genética , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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