BECAS
WETTEN Paula
congresos y reuniones científicas
Título:
EVALUACIÓN Y OPTIMIZACIÓN DE LA CALIDAD OVOCITARIA PARA MEJORAR EL ÉXITO DE LAS TÉCNICAS DE REPRODUCCIÓN ASISTIDA
Autor/es:
WETTEN P.A.; KLINSKY LAHOZ O.G.; MICHAUT, M.A.
Lugar:
Mendoza
Reunión:
Congreso; XL REUNIÓN ANUAL DE LA SOCIEDAD DE BIOLOGIA DE CUYO; 2022
Institución organizadora:
Sociedad de Biología de Cuyo
Resumen:
In assisted reproduction technologies (ART), oocytes are inevitably subjected to postovulatory aging. Although quite significanttechnical progress has been made to improve ART technologies, poor oocyte quality is the crucial factor closely associated with ARTfailure. Understanding the subjacent mechanisms in the oocyte aging process and finding chemicals that can prevent postovulatory agingare two of the most important research topics today. In previous work, we showed that ROS levels increased during in vitro mouseoocyte aging. In addition, we also observed that: 1) cortical granules density (CGD) decreased, indicating premature exocytosis, and 2)the localization of alpha-SNAP and NSF, two proteins involved in membrane fusion during cortical granule exocytosis, were altered inpostovulatory in vitro aged oocytes. Dithiothreitol (DTT) is a dithiol with two end sulfhydryl groups that works as an antioxidant. Wehypothesized that DTT treatment might prevent the aforementioned alterations during in vitro mouse oocyte aging. Mature oocytes wereobtained from hormonally stimulated CF-1 female mice (8-12 weeks of age). To achieve in vitro aging, oocytes were collected 16 h posthCG (time 0 h, control oocytes) and in vitro cultured by 4 or 8 h (aged oocytes) in the presence or absence of DTT. ROS levels weremeasured using the fluorescent indicator DCF-DA. When in vitro oocyte aging was performed in presence of DTT, ROS levelsdiminished significantly to similar levels observed in control oocytes. To determine the DTT effect on the premature cortical granuleexocytosis, mouse oocytes were aged in presence of DTT, fixed, and stained with fluorescent LCA to label cortical granules. Resultsshowed that aged oocytes incubated with DTT had a CGD akin to control oocytes. Likewise, indirect immunofluorescence analysis of theof alpha-SNAP and NSF localizations, showed that in aged oocytes treated with DTT both proteins had a similar distribution pattern tocontrol oocytes. Altogether, these results suggest that the addition of antioxidants to the culture medium might be useful to avoid thealterations produced by the postovulatory in vitro oocyte aging and consequently improve the ART rate success.