RESUMEN
Fetal growth restriction (FGR) is a major obstetric complication stemming from poor placental development. We have previously demonstrated that paternal obesity in mice is associated with impaired embryo development and significantly reduced fetal and placental weights. We hypothesised that the FGR observed in our rodent model of paternal diet-induced obesity is associated with alterations in metabolic, cell signalling and stress pathways. Male C57BL/6 mice were fed either a normal or high-fat diet for 10 weeks before sperm collection for IVF and subsequent embryo transfer. On embryonic day 14, placentas were collected and RNA extracted from both male and female placentas to assess mRNA expression of 24 target genes using custom RT-qPCR arrays. Peroxisome proliferator-activated receptor alpha (Ppara) and caspase-12 (Casp12) expression were significantly altered in male placentas from obese fathers compared with normal (P<0.05), but not female placentas. PPARA and CASP12 proteins were localised within the placenta to trophoblast giant cells by immunohistochemistry, and relative protein abundance was determined by western blot analysis. DNA was also extracted from the same placentas to determine methylation status. Global DNA methylation was significantly increased in female placentas from obese fathers compared with normal (P<0.05), but not male placentas. In this study, we demonstrate for the first time that paternal obesity is associated with changes in gene expression and methylation status of extraembryonic tissue in a sex-specific manner. These findings reinforce the negative consequences of paternal obesity before conception, and emphasise the need for more lifestyle advice for prospective fathers.
Asunto(s)
Dieta Alta en Grasa/efectos adversos , Padre , Retardo del Crecimiento Fetal/metabolismo , Obesidad/complicaciones , Placenta/metabolismo , Placentación/fisiología , Animales , Blastocisto/citología , Blastocisto/metabolismo , Western Blotting , Caspasa 12/genética , Caspasa 12/metabolismo , Células Cultivadas , Metilación de ADN , Embrión de Mamíferos/citología , Embrión de Mamíferos/metabolismo , Femenino , Fertilización In Vitro , Retardo del Crecimiento Fetal/etiología , Retardo del Crecimiento Fetal/patología , Viabilidad Fetal , Técnicas para Inmunoenzimas , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/fisiopatología , PPAR alfa/genética , PPAR alfa/metabolismo , Placenta/citología , Embarazo , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Aumento de PesoAsunto(s)
Humanos , Enfermedades del Sistema Endocrino/terapia , Endocrinología/educación , Hormonas/clasificación , Medicina Basada en la Evidencia , Sistema Endocrino/anatomía & histología , Sistema Endocrino/fisiología , Glándulas Endocrinas , Hipotálamo , Hipófisis , Hormona de Crecimiento Humana , Hormonas Tiroideas , Neoplasia Endocrina MúltipleRESUMEN
We characterized T3 efflux in primary cultures of cells derived from human placenta, neonatal rat cardiac myocytes, and rat inner medullary collecting ducts (IMCD). The T3 efflux rate was highest in placenta cells, followed by ventriculocytes, atriocytes, and IMCD cells. Verapamil reversibly blocked [125I]T3 efflux in these cells in a manner that correlated with their T3 efflux rate. Thus, verapamil inhibition of [125I]T3 efflux in placenta cells led to a 432% increase in the [125I]T3 content compared with 33% increase in IMCD cells. Several unlabeled iodothyronines, but not TRIAC, differentially blocked [125I]T3 efflux such as (T4 > T3 > rT3 = D-T3 > D-T4) in placenta cells and (T4 > rT3 = D-T4 = T3 > D-T3) in ventriculocytes, suggesting tissue-specific differences in the carriers/transporters responsible for T3 efflux. This hypothesis draws further support from the fact that D-T3 inhibited [125I]T3 efflux in placenta cells, but not in ventriculocytes. TRIAC did not affect T3 efflux in ventriculocytes or placenta cells, but it greatly inhibited [125I]T3 uptake in these cells, suggesting that [125I]T3 uptake and efflux mechanisms are distinct and appear to be mediated by distinct carrier/transporter proteins. Collectively, these data suggest that differences in thyroid hormone transport in target cells may provide an important mechanism for regulating hormone action in a tissue-specific fashion.