Resveratrol supplementation during in vitro maturation: effect on the quality of oocyte in species of veterinary interest

The oocyte quality represents a crucial factor in the outcomes of in vitro embryo production.However, different intrinsic and extrinsic conditions can impair the quality of mammalian oocytes, decreasing their developmental competence. The general aim of this thesis was to evaluate the effect of supplementation of resveratrol (resv), a natural antioxidant, during in vitro maturation on the quality of oocytes, in species of veterinary interest (domestic cat, prepubertal goats and sheep).The research includes three different studies which were performed to test the potential beneficial influence of resveratrol to improve the in vitro developmental competence of poor-quality oocytes such as oocytes under sub-optimal condition (oocytes retrieved from domestic cat cold stored ovaries study I, and ovine oocytes exposed to environmental contaminants, study III) and with low developmental competence (oocytes from prepubertal goats, study II).In the three studies the addition of resv during IVM allowed to improve fertilization and development to the blastocyst stage compared to control groups.The mechanism underlying resv effect included regulation of bioenergetic / redox status of the oocytes by the modulation of mitochondrial activity and intra-cytoplasmic levels of reactive oxygen species and glutathione. Resveratrol also promoted normal cortical granules and mitochondria distribution, essential for correct cytoplasmic maturation.