The use of Assisted Reproductive Technologies (ARTs) in modern cattle breeding is an important tool for improving the production of dairy and beef cattle. A frequently employed ART in the cattle industry is in vitro production of embryos. However, bovine in vitro produced embryos differ greatly from their in vivo produced counterparts in many facets, including developmental competence. The lower developmental capacity of these embryos could be due to the stress to which the gametes and/or embryos are exposed during in vitro embryo production, specifically ovarian hormonal stimulation, follicular aspiration, oocyte in vitro maturation in hormone supplemented medium, sperm handling, gamete cryopreservation, and culture of embryos. The negative effects of some ARTs on embryo development could, at least partially, be explained by disruption of the physiological epigenetic profile of the gametes and/or embryos. Here, we review the current literature with regard to the putative link between ARTs used in bovine ...

La producción de embriones in vitro es una de las biotecnologías de la reproducción animal que ha presentado mayor desarrollo en las últimas dos décadas; sin embargo, los resultados exitosos en estos procedimientos dependen de múltiples factores, entre ellos la presencia de especies reactivas de oxígeno, debido a que el proceso de fertilización in vitro y la manipulación de los gametos y embriones expone a las células a factores endógenos y exógenos que pueden afectar los mecanismos de defensa antioxidante y por consiguiente la calidad de los gametos y embriones. En esta revisión se discutirán algunas fuentes de especies reactivas de oxígeno, el uso de antioxidantes enzimáticos, no enzimáticos y polifenólicos para disminuir el estrés oxidativo en los procesos de producción in vitro de embriones, y su efecto sobre la calidad de los oocitos y embriones, la expresión génica y su competencia para el desarrollo embrionario.

Although vitrification is the current method of choice for oocyte and embryo cryopreservation, it may have detrimental effects on reduction–oxidation status and mitochondrial activity. The aim of this study was to evaluate the effect of supplementing in vitro culture (IVC) media and/or vitrification solutions with the antioxidant resveratrol on active mitochondria, mitochondrial superoxide production and lipid peroxidation. Abattoir-derived oocytes were matured and fertilised in vitro using standard procedures. Following IVF (21 h later), zygotes were cultured in IVC medium supplemented with 0 or 0.5 µM resveratrol. On Day 7, blastocysts were vitrified using the Cryotech Vitrification Kit (Cryo Tech Laboratory) with or without 0.5 µM resveratrol. After warming, active mitochondria, mitochondrial superoxide production and lipid peroxidation were evaluated using Mito Tracker Green FM, MitoSOX Red and BODIPY581/591 C11 staining respectively. The vitrification–warming process significantly increased active mitochondria and mitochondrial superoxide production in bovine embryos (P < 0.05, ANOVA). The addition of 0.5 µM resveratrol to the IVC medium or vitrification solutions significantly attenuated the increase in active mitochondria (P < 0.05), but not in mitochondrial superoxide production, whereas embryos cultured and vitrified with resveratrol showed the highest values for both parameters (P < 0.05). Regarding lipid peroxidation, no significant differences were detected between treatments. In conclusion, resveratrol supplementation of IVC medium or vitrification solutions contributes to recovery of an embryo’s ‘quieter’ state (i.e. lower oxidative metabolism) after vitrification. However, supplementation of both solutions with resveratrol seemed to have a pro-oxidant effect.