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1.
Artigo em Inglês | MEDLINE | ID: mdl-32437254

RESUMO

Copper is an environmental risk factor, which has various effects on reproductive endocrinology. In this study human adrenocortical carcinoma (NCI-H295R) cell line was used as an in vitro biological model to study the effect of copper sulfate (CuSO4.5H2O) on steroidogenesis and cytotoxicity. The cell cultures were exposed to different concentrations (3.90, 62.50, 250, 500, 1000 µM) of CuSO4.5H2O and compared to control group (medium without CuSO4.5H2O). Cell viability was measured by the metabolic activity assay. Quantification of sexual steroid production directly from the medium was performed by ELISA assay. Following 48 h culture of NCI-H295R cell line in the presence of CuSO4.5H2O a dose-dependent depletion of progesterone release was observed even at the lower concentrations of CuSO4.5H2O. The lowest levels of progesterone were detected in groups with the higher doses (≥ 250 µM) of CuSO4.5H2O, which elicited significant cytotoxic action. Testosterone production decreased significantly, and this decline was more prominent in comparison to that of progesterone. The lowest release of testosterone was recorded at 1000 µM of CuSO4.5H2O. The cytotoxic effect of CuSO4.5H2O was evident at all concentrations used in the study. The presented data suggest that copper has detrimental effects on sexual steroid hormones and consecutively on reproductive physiology.


Assuntos
Sulfato de Cobre/toxicidade , Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Progesterona/biossíntese , Testosterona/biossíntese , Bioensaio , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos
2.
Artigo em Inglês | MEDLINE | ID: mdl-30925854

RESUMO

The aim of our in vitro study was to assess the potential effect of 4-octylphenol (4-OP) on the basal and human chorionic gonadotropin (hCG)-stimulated cholesterol levels and biosynthesis of steroid hormones in cultured mouse Leydig cells. In addition, we evaluated the intracellular superoxide production following 4-OP treatment. Isolated mouse Leydig cells were cultured in the presence or absence of 1 IU/mL (hCG) with the addition of 0.04; 0.2; 1.0; 2.5 and 5.0 µg/mL 4-OP during 44 h. The level of cholesterol was determined from the culture medium using photometry. Quantification of steroid hormones was performed by the enzyme linked immunosorbent assay and intracellular generation of superoxide radicals was assessed by the nitroblue-tetrazolium assay. Administered concentrations of 4-OP (0.04-5.0 µg/mL) did not affect basal and hCG-stimulated cholesterol level significantly. However, basal DHEA secretion was increased significantly (P < 0.001) in the highest experimental dose (5 µg/mL) of 4-OP. By hCG-stimulated DHEA secretion, a significant (P < 0.001) decrease was recorded at 5.0 µg/mL 4-OP in comparison to the control group. The stimulatory effect of 4-OP was also confirmed in androstenedione secretion, when 2.5 and 5.0 µg/mL increased hormone secretion significantly (P˂0.05; P˂0.001). Exposure to experimental concentrations (0.04 to 5.0 µg/mL) of tested chemical reduced hCG-stimulated androstenedione formation, but not significantly. Measurements of basal testosterone production have shown significant (P˂0.01; P˂0.001) increase at 1.0; 2.5 and 5.0 µg/mL of 4-OP. Furthermore, 44 h treatment by 4-OP (1.0-5.0 µg/mL) caused significant (P˂0.01; P˂0.001) intracellular accumulation of superoxide radicals in exposed cells. A considerably more detailed and systematic research is required for a better understanding of risks associated with male reproductive system in humans and wildlife.


Assuntos
Androgênios/metabolismo , Gonadotropina Coriônica/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Fenóis/farmacologia , Superóxidos/metabolismo , Androstenodiona/metabolismo , Animais , Células Cultivadas , Humanos , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testosterona/biossíntese
3.
Chemosphere ; 199: 747-754, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29478761

RESUMO

Over the last decade, there is growing incidence of male reproductive malfunctions. It has been documented that numerous environmental contaminants, such as endocrine disruptors (EDs) may adversely affect the reproductive functions of humans as well as wildlife species. The aim of this in vitro study was to examine the effects of 4-octylphenol (4-OP) on the steroidogenesis in mice Leydig cells. We evaluated the impact of this endocrine disruptor on the cholesterol levels and hormone secretion in a primary culture. Subsequently, we determined the cell viability and generation of reactive oxygen species (ROS) following 4-OP treatment. Isolated mice Leydig cells were cultured in the presence of different 4-OP concentrations (0.04-5.0 µg/mL) and 1 mM cyclic adenosine-monophosphate during 44 h. Cholesterol levels were determined from the culture medium using photometry. Quantification of steroid secretion was performed by enzyme-linked immunosorbent assay. The cell viability was assessed using the metabolic activity assay, while ROS production was assessed by the chemiluminescence technique. Slightly increased cholesterol levels were recorded following exposure to the whole applied range of 4-OP, without significant changes (P>0.05). In contrast, the secretion of steroid hormones, specifically dehydroepiandrosterone, androstenedione, and testosterone was decreased following exposure to 4-OP. Experimental doses of 4-OP did not affect cell viability significantly; however a moderate decrease was recorded following the higher doses (2.5 and 5.0 µg/mL) of 4-OP. Furthermore, relative treatment of 4-OP (5.0 µg/mL) caused a significant (P < 0.001) ROS overproduction in the exposed cells.


Assuntos
AMP Cíclico/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Fenóis/farmacologia , Monofosfato de Adenosina/metabolismo , Androstenodiona , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , AMP Cíclico/metabolismo , Disruptores Endócrinos/metabolismo , Humanos , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Esteroides/biossíntese , Testosterona/metabolismo
4.
Environ Pollut ; 222: 219-225, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28104344

RESUMO

Nonylphenol is considered an endocrine disruptor and has been reported to affect male reproductive functions. In our in vitro study, we evaluated the effects of 4-nonylphenol (4-NP) on cholesterol levels, hormone formation and viability in cultured Leydig cells from adult ICR male mice. We also determined the potential impact of 4-NP on generation of reactive oxygen species (ROS) after 44 h of cultivation. The cells were cultured with addition of 0.04; 0.2; 1.0; 2.5 and 5.0 µg/mL of 4-NP in the present of 1 IU/mL human chorionic gonadotropin (hCG) and compared to the control. The quantity of cholesterol was determined from culture medium using photometry. Determination of hormone production was performed by enzyme-linked immunosorbent assay. Metabolic activity assay was used for quantification of cell viability. The chemiluminescence technique, which uses a luminometer to measure reactive oxygen species, was employed. Applied doses of 4-NP (0.04-5.0 µg/mL) slight increase cholesterol levels and decrease production of dehydroepiandrosterone after 44 h of cultivation, but not significantly. Incubation of 4-NP treated cells with hCG significantly (P < 0.001) inhibited androstenedione, but not testosterone, formation at the highest concentration (5.0 µg/mL). The viability was significantly (P < 0.05); (P < 0.001) increased at 1.0; 2.5 and 5.0 µg/mL of 4-NP after 44 h treatment. Furthermore, 44 h treatment of 4-NP (0.04-5.0 µg/mL) caused significant (P < 0.001) intracellular accumulation of ROS in exposed cells. Taken together, the results of our in vitro study reported herein is consistent with the conclusion that 4-nonylphenol is able to influence hormonal profile, cell viability and generate ROS.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Gonadotropina Coriônica/metabolismo , Disruptores Endócrinos/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Fenóis/farmacologia , Androstenodiona/metabolismo , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Células Intersticiais do Testículo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fenóis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testosterona/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-27835057

RESUMO

In this study, the human H295R adrenocarcinoma cell line was exposed to different concentrations (0.04, 0.2, 1.0, 2.5 or 5 µg/mL) of nonylphenol (NP) to investigate its impact on the inhibition or induction of the steroid hormones production during 48 h of in vitro culture. The hormone production was measured using ELISA kits. Results of this in vitro study suggest various effect of nonylphenol in relatively low concentrations on the selected steroid hormones production by the human H295R adrenocarcinoma cell line. The inhibiting impact on progesterone and androstenedione production was observed. The amount of progesterone was significantly decreased at 1.0, 2.5 and 5 µg/mL NP. Equally, the androstenedione production significantly decreased at 5 µg/mL NP. On the other hand, the amount of testosterone and 17ß-estradiol was induced after nonylphenol exposition. The significant increase of testosterone level was found out at treatment with 5 µg/mL NP. 17ß-estradiol production significantly increased at the doses of 2.5 and 5 µg/mL NP.


Assuntos
Linhagem Celular Tumoral/efeitos dos fármacos , Disruptores Endócrinos/farmacologia , Fenóis/farmacologia , Neoplasias do Córtex Suprarrenal/metabolismo , Linhagem Celular Tumoral/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Estradiol/biossíntese , Humanos , Progesterona/biossíntese , Esteroides/biossíntese , Testosterona/biossíntese , Testes de Toxicidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-25723060

RESUMO

Cadmium (Cd) is a known endocrine disruptor with the ability to affect the production of hormones involved in the regulation of reproductive processes. In this study human adrenocortical carcinoma cell line NCI-H295R was used as an in vitro biological model to study the effect of cadmium (CdCl2) on steroidogenesis. The cell cultures were exposed to different concentrations of CdCl2 (1.90, 3.90, 7.80, 15.60, 31.20 and 62.50 µM) and compared to control (medium without CdCl2). Cell viability was measured by the metabolic activity (MTT) assay for estimation of mitochondria structural integrity. Quantification of sexual steroid production directly from aliquots of the medium was performed by enzyme linked immunosorbent assay (ELISA). Following 48 h culture of the cells in the presence of CdCl2 a concentration-dependent depletion in progesterone production was observed at the lower concentrations of CdCl2. The lowest amount of progesterone was significantly detected in groups with the higher doses (≥ 31.20 µM) of CdCl2, which elicited significant (P < 0.01) cytotoxic action, too. Cadmium decreased testosterone release in the whole applied range even at the lower concentration of CdCl2. The release of 17ß-estradiol decreased as well, but the decline was less pronounced compared to decrease of progesterone and testosterone. The cytotoxic effect was significantly (P < 0.01) detected at all concentrations of CdCl2 (1.90-62.50 µM) used in the study. However, the cell viability remained relatively high (>75%) up to 7.80 µM of CdCl2 and significantly (P < 0.01) decreased at 15.60 µM and higher concentrations of CdCl2. These results suggest that cadmium has endocrine disruptive effects on sexual steroid synthesis even at very low concentrations.


Assuntos
Cloreto de Cádmio/toxicidade , Disruptores Endócrinos/toxicidade , Estradiol/biossíntese , Progesterona/biossíntese , Testosterona/biossíntese , Testes de Toxicidade/métodos , Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/metabolismo , Carcinoma Adrenocortical/patologia , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Humanos
7.
Artigo em Inglês | MEDLINE | ID: mdl-23245310

RESUMO

In this study the NCI-H295R human adrenocortical carcinoma cell line was used as an in vitro biological model to study the effect of mercury (HgCl(2)) on the steroidogenesis. The cells were cultured for 48 h with addition of 1.0; 5.0; 25; 50 or 100 µM of HgCl(2) and compared to control. Cell viability was measured by the MTT (metabolic activity) assay estimation for the mitochondria structural integrity. Quantification of testosterone and progesterone directly from aliquots of the medium was performed by enzyme linked immunosorbent assay (ELISA). Concentration-dependent depression in testosterone production was detected particularly for higher concentration of Hg(2+). Progesterone production was also decreased, but at the lower concentrations (1.0 and 5.0 µM) of Hg(2+) this decline was lower compared to depression of testosterone. The cell viability significantly decreased at 25 µM and higher concentration of Hg(2+). However, at 25 µM Hg(2+) exposure the cell viability remained relatively high (> 80%). Results of the study indicate dose-dependent decreases in both testosterone and progesterone production of H295R cell culture following a 48 h in vitro HgCl(2) exposure. The results suggest that Hg has detrimental effects on steroid hormone synthesis also at very low concentrations and consecutively on reproductive physiology.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Cloreto de Mercúrio/toxicidade , Progesterona/biossíntese , Testosterona/biossíntese , Glândulas Suprarrenais/citologia , Glândulas Suprarrenais/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Humanos , Espectrofotometria , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-22540648

RESUMO

The goal of this minireview is to summarize our current knowledge on the reproductive toxicity of soluble nickel salts. We made an attempt to present the most relevant data obtained from in vivo and in vitro experiments performed on mammals, mammalian primary cell cultures and cell lines. Nickel has been demonstrated to disturb the mammalian reproductive functions at several levels of regulation. The results of previous investigations indicate that the hormonal effects may play an important role in the reproductive toxicology of nickel both at the neuroendocrine and gonadal levels in the hypothalamic-pituitary-gonadal (HPG) axis. At the molecular level, it may be important that nickel may substitute certain other metals in metal dependent enzymes, leading to an altered protein function. It readily crosses the cell membrane via calcium channels and competes with calcium for specific receptors. Nickel can cross-link aminoacids to DNA, lead to formation of reactive oxygen species (ROS), moreover mimic hypoxia. These changes may lead to the activation of some signaling pathways, subsequent transcription factors and eventually to alterations in gene expression and cellular metabolism. These events are likely to be involved in the reproductive toxicity of nickel.


Assuntos
Níquel/toxicidade , Reprodução/efeitos dos fármacos , Animais , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Masculino , Camundongos
9.
J Environ Sci Health B ; 46(8): 773-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21902555

RESUMO

This investigation was undertaken to elucidate whether the active metabolite of malathion, malaoxon, has any role in exerting cyto- and genotoxic effects for human choriocarcinoma (JAR) cell line which is an acceptable model for human placental cells. Gas chromatography-mass spectrometry (GC-MS) analysis were separately performed on the cell compartment and supernatant cell culture medium after subjecting the cell line to different malathion concentrations (10-400 µg/mL) and for various incubation periods (0.5 to 24 hours). GC-MS analysis showed that the sonication performed for the disruption of the cells did not cause the chemical change of malathion. The uptake of malathion by the cells was relatively fast. However, the presence of malaoxon, even in trace amounts, could not be confirmed either in samples originating from disrupted cells or in the cell culture medium. Although the hydrolysis of malaoxon occurred in the culture medium, this degradation process could not be counted as a reason for the absence of malaoxon. Since both malathion and malaoxon standard compounds could be accurately detected and distinguished by the applied liquid-liquid extraction and GC-MS methods, one can conclude that, in the case of JAR cells, the parent compound, (i.e. malathion itself) is responsible for the observed in vitro cyto- and genotoxic effects. Our results indicate that the direct toxicity of malathion contributes to the complications of pregnancy observed for environmental malathion exposure.


Assuntos
Coriocarcinoma/metabolismo , Malation/análogos & derivados , Malation/toxicidade , Mutagênicos/toxicidade , Linhagem Celular Tumoral , Coriocarcinoma/tratamento farmacológico , Coriocarcinoma/genética , Dano ao DNA/efeitos dos fármacos , Humanos , Malation/metabolismo , Mutagênicos/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-17558766

RESUMO

In this study effects of mercury administration on the kidney and testicular structure of adult rats were evaluated. Rats received mercury (HgCl2) in single intraperitoneal dose 20 mg HgCl2 (group A), 10 mg HgCl2 (group B) and 5 mg HgCl2 (group C) per kilogram of body weight and were killed after 48 hours following mercury administration. After the preparation of histological samples the results were compared with control group (K). In kidney decreased diameters of glomeruli and renal corpuscles, damaged tubules with affected quality of tubular cells and infiltration of interstitium were detected. Quantitative analysis demonstrated increased relative volume of tubules and renal corpuscles. Also the number of nuclei and glomeruli was increased in all experimental groups. The diameter of glomeruli and renal corpuscles was decreased. In testis undulation of basal membrane, dilatation of blood vessels in interstitium and occurrence of empty spaces in germinal epithelium were observed. Decreased relative volume of germinal epithelium, increased relative volume of interstitium and increased apoptosis occurrence suggest damaged interstitium and revealed occurrence of edemas. The relative volume of seminiferous tubules showed higher luminization. The number of nuclei was decreased in all experimental groups what is in positive relation with occurrence of empty spaces. Also other evaluated criteria demonstrated significant differences between control group and experimental groups. This study reports a negative effect of mercury on the structure and function of kidney and testes.


Assuntos
Rim/efeitos dos fármacos , Mercúrio/toxicidade , Testículo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Rim/patologia , Masculino , Microscopia de Fluorescência , Ratos , Ratos Wistar , Testículo/patologia
11.
Artigo em Inglês | MEDLINE | ID: mdl-17454374

RESUMO

The purpose of this study was to assess the effects of lead administration on the kidney and testicular structure of adult rats. Rats received lead (PbNO(3)) in single intraperitoneal dose 50 mg/kg (group A), 25 mg/kg (group B) and 12.5 mg (group C) per kilogram of body weight and were killed 48 h following lead administration. After the preparation of histological samples the results were compared with control. After the lead administration dilated Bowman's capsules and blood vessels in interstitium of kidney with evident hemorrhagic alterations were noted. Quantitative analysis determined increased relative volume of interstitium and tubules. Also, the diameter of renal corpuscules, diameter of glomeruli and diameter of Bowman's capsule were significantly increased, especially in group A, with the highest lead concentration. In testes, dilatation of blood capillaries in interstitium, undulation of basal membrane and occurrence of empty spaces in seminiferous epithelium were detected. An apoptosis assay confirmed increased incidence of apoptosis in the spermatogenetic cells after the lead administration. Also further morphometric analysis showed significant differences in evaluated parameters between control and treated groups. The number of cell nuclei was decreased in lead-treated groups, which is concerned with the occurrence of empty spaces as well as with the higher apoptosis incidence in germinal epithelium. This study reports a negative effect of lead on the structure and function of kidney and testes.


Assuntos
Rim/efeitos dos fármacos , Chumbo/toxicidade , Testículo/efeitos dos fármacos , Animais , Rim/fisiologia , Chumbo/administração & dosagem , Masculino , Ratos , Ratos Wistar , Testículo/fisiologia
12.
Reprod Toxicol ; 22(1): 111-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16434166

RESUMO

The aim of our study was to evaluate the possible effects of whole-body 1800 MHz GSM-like microwave exposure on male reproduction. After repeated exposure of mice to microwaves at 0.018-0.023 W/kg whole-body specific energy absorption rate (SAR) an elevated serum testosterone level was measured, but no microwave exposure related histopathological alteration could be detected in the reproductive organs. The in vitro steroidogenic response of 48 h Leydig cell cultures obtained from exposed animals did not differ from the controls, suggesting that Leydig cells were not the primary targets of the applied microwave exposure or direct action of microwaves on Leydig cells was temporary only. In exposed animals the red blood cell count and volume of packed red cells were also increased. Further investigations are required to clarify the mechanism of action of the applied microwave exposure on male mice, as well as to establish the biological significance of the observed phenomena.


Assuntos
Micro-Ondas/efeitos adversos , Hormônios Testiculares/biossíntese , Testículo/efeitos da radiação , Irradiação Corporal Total/métodos , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal/efeitos da radiação , Células Cultivadas , Colesterol/sangue , Contagem de Eritrócitos , Técnicas In Vitro , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos , Doses de Radiação , Testículo/metabolismo , Testosterona/biossíntese , Triglicerídeos/sangue
13.
Magy Onkol ; 49(2): 149-51, 2005.
Artigo em Húngaro | MEDLINE | ID: mdl-16249811

RESUMO

The aim of this study was to evaluate the possible effects of in vivo 1800 MHz GSM-like exposure on male reproduction. In five separate experiments, male NMRI mice (35-41 g) were exposed (11-12 mice each) to 1800 MHz GSM-like radiation. The average power density was 100 microW/cm2, the estimated SAR was 0.018-0.023 W/kg. The animals were exposed ten times (over two weeks on workdays) and the duration of exposure was 2 h/day. On the day of the last treatment, mice were anesthetized with i.p. pentobarbital, and blood samples were taken for hematology, serum chemistry and serum testosterone (T) determinations (ELISA). Testicles, epididymes, adrenals, prostates and pituitary glands were removed for histology. One testicle of each animal was used for culture of Leydig cells. The cells were cultured for 48 h in the presence or absence of human chorionic gonadotropin (hCG) to evaluate the in vitro steroidogenic response of Leydig cells. In the exposed animals red blood cell count (RBC: 8.59+/-0.10 T/l, n=37) and volume of packed red cells (VPRC: 42.29+/-0.43%, n=37) were significantly higher (p<0.01) compared with the controls (RBC: 8.12+/-0.08 T/l, n=36; VPRC: 39.76+/-0.36%, n=36). The serum testosterone level of the exposed animals (7.85+/-1.08 ng/ml, n=56) was also significantly elevated (p<0.05) compared to the controls (5.12+/-0.79, n=52), while the in vitro steroidogenic capacity of the Leydig cells was unaltered. No significant differences in the other investigated variables were found between controls and exposed mice. Our results indicate that the applied GSM-like microwave exposure may induce slight, but statistically significant alterations in some hematological and endocrine parameters of male mice within the physiological range. Further investigations are required to establish the biological significance of these phenomena.


Assuntos
Biomarcadores/sangue , Campos Eletromagnéticos/efeitos adversos , Gônadas/efeitos da radiação , Micro-Ondas/efeitos adversos , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Colesterol/sangue , Relação Dose-Resposta à Radiação , Contagem de Eritrócitos , Hematócrito , Hemoglobinas/metabolismo , Contagem de Leucócitos , Masculino , Camundongos , Contagem de Plaquetas , Doses de Radiação , Triglicerídeos/sangue
14.
ScientificWorldJournal ; 4 Suppl 2: 75-82, 2004 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-15517105

RESUMO

Adherens (AJ) and tight junctions (TJ), as integrated parts of the junctional complex, are multifunctional specialized regions of the cell membrane in epithelial cells. They are responsible for cell-to-cell interactions and also have great importance in cellular signaling processes including Wnt protein-mediated signals. As electromagnetic field (EMF) exposure is known to cause alterations in the function as well as supramolecular organization of different cell contacts, our goal was to investigate the effect of 50-Hz magnetic field (MF) exposures on the subcellular distribution of some representative structural proteins (occludin, beta-catenin, and cadherin) found in AJ and TJ. Additionally, cellular beta-catenin content was also quantified by Western blot analysis. 50-Hz MF exposures seemed to increase the staining intensity (amount) of occludin, cadherins, and beta-catenin in the junctional area of MDCK cells, while Western blot data indicated the quantity of beta-catenin was found significantly decreased at both time points after EM exposures. Our results demonstrate that MF are able to modify the distribution of TJ and AJ structural proteins, tending to stabilize these cell contacts. The quantitative changes of beta-catenin suggest a causative relationship between MF effects on the cell junctional complex and the Wnt signaling pathway.


Assuntos
Junções Aderentes/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Rim/efeitos da radiação , Junções Íntimas/efeitos da radiação , Animais , Linhagem Celular , Cães , Rim/citologia , Doses de Radiação , Lesões Experimentais por Radiação/patologia , Radiação não Ionizante/efeitos adversos
15.
ScientificWorldJournal ; 4 Suppl 2: 83-90, 2004 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-15517106

RESUMO

The main goal of this study was to evaluate the possible effect of whole-body magnetic field (MF) exposure on the steroidogenic capacity of Leydig cells in vitro. In four separate experiments, male CFLP mice were exposed to sinusoidal 50-Hz, 100-microT MF. The duration of exposure was 23.5 h/day over a period of 14 days. At the end of the exposure, interstitial (Leydig) cells were isolated from the testicles of the sham-exposed and exposed animals. The cells were cultured for 48 h in the presence or absence of 1, 10, or 100 mIU/ml human chorionic gonadotropin (hCG). The luteinizing hormone (LH) analog hCG was used to check the testosterone (T) response of the sham-exposed controls and to evaluate the possible effect of the whole-body MF exposure on the steroidogenic capacity of Leydig cells in vitro. Testosterone content of the culture media and blood sera was measured by radioimmunoassay (RIA). In the cultures obtained from MF-exposed animals, the hCG-stimulated T response was significantly higher (p < 0.01) compared with the sham-exposed controls, while the basal T production of cells and the level of serum T remained unaltered. No MF exposure-related histopathological alterations were found in testicles, epididymes, adrenals, prostates, and pituitary glands. The MF exposure did not affect the animal growth rate and the observed hematologic and serum chemical variables. Our results indicate a presumably direct effect of whole-body MF exposure on the hCG-stimulated steroidogenic response of mouse Leydig cells.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Células Intersticiais do Testículo/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Glândulas Suprarrenais/fisiologia , Glândulas Suprarrenais/efeitos da radiação , Animais , Peso Corporal/efeitos da radiação , Células Cultivadas , Epididimo/patologia , Epididimo/efeitos da radiação , Humanos , Células Intersticiais do Testículo/química , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Hipófise/patologia , Hipófise/efeitos da radiação , Próstata/patologia , Próstata/efeitos da radiação , Doses de Radiação , Lesões Experimentais por Radiação/sangue , Radiação não Ionizante/efeitos adversos , Testículo/patologia , Testículo/efeitos da radiação , Testosterona/biossíntese , Testosterona/sangue , Irradiação Corporal Total/métodos
16.
Toxicol Mech Methods ; 14(5): 287-92, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-20021108

RESUMO

Human ovarian granulosa cells obtained from women undergoing in vitro fertilization were exposed to 15.6, 31.25, 62.5, 125, 250, 500, 1000 muM Ni(2+) for 48 h. To determine the site of action of Ni(2+), the granulosa cells were stimulated to produce progesterone (P) by using maximally stimulating amounts of human chorionic gonadotropin (0.1 IU/ml hCG) or dibutyryl cyclic adenosine monophosphate (1 mM db-cAMP). The luteinizing hormone (LH) analog hCG was chosen because resultant P production requires an intact membrane receptor and db-cAMP was used to test for post LH receptor defects caused by Ni(2+). Progesterone content of the culture medium was determined by radioimmunoassay (RIA), and viability of the cells was measured by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) reduction test. Concentration-dependent depression in both hGC and db-cAMP stimulated P production was seen at 15.625 muM or higher concentration of Ni(2+), which is not cytotoxic on human ovarian granulosa cells. The viability of cells was unaffected up to 31.25 muM and decreased significantly at 62.5 muM. Our results show a dose-related depression in stimulated P production of granulosa cells at a dose that does not induce significant cytotoxic action. These data indicate that the effect of Ni(2+) on P production is not due to cytotoxicity, and the cellular site(s) of inhibitory action appears to be subsequent to the membrane receptor and production of cAMP.

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