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1.
J Nutr Biochem ; 34: 17-29, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27162022

RESUMEN

Benzo(a)pyrene [B(a)P] is an environmental toxicant that alters the steroidogenic profile of testis and induces testicular dysfunction. In the present study, we have investigated the molecular signaling of B(a)P and the ameliorative potential of the natural aryl hydrocarbon receptor (AhR) antagonist and antioxidant, resveratrol, on B(a)P-induced male reproductive toxicity. Studies showed that B(a)P treatment resulted in p38 MAPK activation and increased inducible nitric oxide synthase (iNOS) production along with testicular apoptosis and steroidogenic dysfunction. Resveratrol cotreatment maintained testicular redox potential, increased serum testosterone level and enhanced expression of major testicular steroidogenic proteins (CYPIIA1, StAR, 3ßHSD, 17ßHSD) and prevented subsequent onset of apoptosis. Resveratrol cotreatment resulted inhibition of testicular cytochrome P4501A1 (CYP1A1) expression, which is the major B(a)P metabolizing agent for BPDE-DNA adduct formation. Resveratrol also significantly decreased the B(a)P-induced AhR protein level, its nuclear translocation and subsequent promoter activation, thereby decreased the expression of CYP1A1. Resveratrol also down-regulated B(a)P-induced testicular iNOS production through suppressing the activation of p38 MAPK and ATF2, thus improved the oxidative status of the testis and prevented apoptosis. Our findings cumulatively suggest that resveratrol inhibits conversion of B(a)P into BPDE by modulating the transcriptional regulation of CYP1A1 and acting as an antioxidant thus prevents B(a)P-induced oxidative stress and testicular apoptosis.


Asunto(s)
Antioxidantes/uso terapéutico , Benzo(a)pireno/antagonistas & inhibidores , Suplementos Dietéticos , Contaminantes Ambientales/antagonistas & inhibidores , Infertilidad Masculina/prevención & control , Estilbenos/uso terapéutico , Testículo/efectos de los fármacos , Factor de Transcripción Activador 2/agonistas , Factor de Transcripción Activador 2/antagonistas & inhibidores , Factor de Transcripción Activador 2/genética , Factor de Transcripción Activador 2/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Antioxidantes/efectos adversos , Apoptosis/efectos de los fármacos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/agonistas , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Benzo(a)pireno/administración & dosificación , Benzo(a)pireno/toxicidad , Citocromo P-450 CYP1A1/antagonistas & inhibidores , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Suplementos Dietéticos/efectos adversos , Relación Dosis-Respuesta a Droga , Contaminantes Ambientales/administración & dosificación , Contaminantes Ambientales/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Infertilidad Masculina/inducido químicamente , Infertilidad Masculina/metabolismo , Infertilidad Masculina/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismo , Estrés Oxidativo/efectos de los fármacos , Regiones Promotoras Genéticas/efectos de los fármacos , Ratas Wistar , Receptores de Hidrocarburo de Aril/agonistas , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Resveratrol , Estilbenos/efectos adversos , Testículo/metabolismo , Testículo/patología , Testosterona/agonistas , Testosterona/antagonistas & inhibidores , Testosterona/sangre
2.
Reprod Biol Endocrinol ; 12: 90, 2014 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-25239217

RESUMEN

BACKGROUND: Aromatase converts testosterone into 17beta-estradiol in granulosa cells, and the converted 17beta-estradiol contributes to follicular maturation. Additionally, excessive testosterone inhibits aromatase activity, which can lead to concerns regarding polycystic ovary syndrome (PCOS). Generally, 1,25-dihydroxyvitamin D3 (1,25D3) supplements help to improve the symptoms of PCOS patients who exhibit low blood levels of 1,25D3. Therefore, this study investigated the interaction effects of 1,25D3 and testosterone on estrogenesis and intercellular connections in rat granulosa cells. METHODS: Primary cultures of granulosa cells were treated with testosterone or testosterone plus 1,25D3, or pre-treated with a calcium channel blocker or calcium chelator. Cell lysates were subjected to western blot analysis to determine protein and phosphorylation levels, and 17beta-estradiol secretion was examined using a radioimmunoassay technique. Cell viability was evaluated by MTT reduction assay. Connexin 43 (Cx43) mRNA and protein expression levels were assessed by qRT-PCR, western blot, and immunocytochemistry. RESULTS: Testosterone treatment (0.1 and 1 microg/mL) increased aromatase expression and 17beta-estradiol secretion, and the addition of 1,25D3 attenuated testosterone (1 microg/mL)-induced aromatase expression but improved testosterone-induced 17beta-estradiol secretion. Furthermore, testosterone-induced aromatase phosphotyrosine levels increased at 10 min, 30 min and 1 h, whereas 1,25D3 increased the longevity of the testosterone effect to 6 h and 24 h. Within 18-24 h of treatment, 1,25D3 markedly enhanced testosterone-induced 17beta-estradiol secretion. Additionally, pre-treatment with a calcium channel blocker nifedipine or an intracellular calcium chelator BAPTA-AM reduced 1,25D3 and testosterone-induced 17beta-estradiol secretion. Groups that underwent testosterone treatment exhibited significantly increased estradiol receptor beta expression levels, which were not affected by 1,25D3. Neither testosterone nor 1,25D3 altered 1,25D3 receptor expression. Finally, at high doses of testosterone, Cx43 protein expression was decreased in granulosa cells, and this effect was reversed by co-treatment with 1,25D3. CONCLUSIONS: These data suggest that 1,25D3 potentially increases testosterone-induced 17beta-estradiol secretion by regulating aromatase phosphotyrosine levels, and calcium increase is involved in both 1,25D3 and testosterone-induced 17beta-estradiol secretion. 1,25D3 reverses the inhibitory effect of testosterone on Cx43 expression in granulosa cells.


Asunto(s)
Calcitriol/metabolismo , Conexina 43/metabolismo , Estradiol/metabolismo , Regulación del Desarrollo de la Expresión Génica , Células de la Granulosa/metabolismo , Testosterona/metabolismo , Regulación hacia Arriba , Animales , Aromatasa/química , Aromatasa/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Quelantes del Calcio/farmacología , Señalización del Calcio/efectos de los fármacos , Células Cultivadas , Conexina 43/agonistas , Conexina 43/antagonistas & inhibidores , Conexina 43/genética , Regulación hacia Abajo/efectos de los fármacos , Estradiol/agonistas , Estradiol/química , Antagonistas de Estrógenos/farmacología , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Células de la Granulosa/citología , Células de la Granulosa/efectos de los fármacos , Fosforilación/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Ratas Sprague-Dawley , Receptores de Estradiol/agonistas , Receptores de Estradiol/antagonistas & inhibidores , Receptores de Estradiol/metabolismo , Testosterona/agonistas , Testosterona/antagonistas & inhibidores , Regulación hacia Arriba/efectos de los fármacos
3.
J Ethnopharmacol ; 153(2): 446-53, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24607508

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Numerous honeybee (Apis mellifera) products have been used in traditional medicine to treat infertility and to increase vitality in both men and women. Drone milk (DM) is a relatively little-known honeybee product with a putative sexual hormone effect. The oestrogenic effect of a fraction of DM has recently been reported in rats. However, no information is available on the androgenic effects of DM. The purpose of the present study was to determine the androgen-like effect of DM in male rats and to identify effective compounds. MATERIALS AND METHODS: A modified Hershberger assay was used to investigate the androgenic effect of crude DM, and the plasma level of testosterone was measured. The prostatic mRNA and protein expression of Spot14-like androgen-inducible protein (SLAP) were also examined with real-time PCR and Western blot techniques. GC-MS and NMR spectroscopic investigations were performed to identify the active components gained by bioactivity-guided fractionation. RESULTS: The crude DM increased the relative weights of the androgen-dependent organs and the plasma testosterone level in castrated rats and these actions were flutamide-sensitive. DM increased the tissue mRNA and protein level of SLAP, providing further evidence of its androgen-like character. After bioactivity-guided fractionation, two fatty acid esters, methyl palmitate (MP) and methyl oleate (MO), were identified as active compounds. MP alone showed an androgenic effect, whereas MO increased the weight of androgen-sensitive tissues and the plasma testosterone level only in combination. CONCLUSION: The experimental data of DM and its active compounds (MO and MP) show androgenic activity confirming the traditional usage of DM. DM or MP or/and MO treatments may project a natural mode for the therapy of male infertility.


Asunto(s)
Andrógenos/farmacología , Abejas , Leche , Ácidos Oléicos/farmacología , Orquiectomía , Palmitatos/farmacología , Andrógenos/aislamiento & purificación , Animales , Femenino , Masculino , Ácidos Oléicos/aislamiento & purificación , Palmitatos/aislamiento & purificación , Próstata/efectos de los fármacos , Próstata/fisiología , Ratas , Ratas Sprague-Dawley , Testosterona/agonistas , Testosterona/sangre
4.
Food Chem Toxicol ; 50(10): 3826-32, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22809474

RESUMEN

Dietary supplements have been used for decades for enhancing muscle growth. The harm caused by some of these products is well documented. We investigated and reported toxic hepatitis in 20 male athletes following self-prescribing of a number of dietary supplements which are lesser known. The patients' ages ranged from 24 to 32 with a mean of 28 years. They had taken three kinds of supplements for 1 year including testosterone optimizer agent T Bomb II, a creatine supplement Phosphagen and an amino acid based supplement Cell-Tech. Based on the history, clinical examination, and laboratory findings the cases were diagnosed as toxic hepatitis. After discontinuation of taking the supplements, clinical recovery and improvement of liver function tests were achieved within 30 days. Causality assessment with the CIOMS (Council for International Organization Medical Sciences) scale showed a "possible" grade of causality (+5 points) for these supplements. It can be concluded that these newer anabolic supplements may induce toxic hepatitis. Since the health risks of them may be severe, the use of these kinds of dietary supplements should be discouraged.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Creatina/efectos adversos , Suplementos Dietéticos/efectos adversos , Deportes , Levantamiento de Peso , Adulto , Aminoácidos , Doping en los Deportes , Fatiga , Humanos , Masculino , Debilidad Muscular , Testosterona/agonistas
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