Lycopene supplementation in serum-free maturation medium improves bovine in vitro embryo development, quality, and modulates embryonic transcriptomic profile

Bovine embryos are typically cultured at reduced oxygen tension to lower the impact of oxidative stress on embryo development. However, oocyte in vitro maturation (IVM) is performed at atmospheric oxygen tension since low oxygen during maturation has a negative impact on oocyte developmental competence. Lycopene, a carotenoid, acts as a powerful antioxidant and may protect the oocyte against oxidative stress during maturation at atmospheric oxygen conditions. Here, we assessed the effect of adding 0.2 µM lycopene (antioxidant), 5 µM menadione (pro-oxidant), and their combination on reactive oxygen species (ROS) generation in mature oocytes and subsequent blastocyst development, quality, and transcriptome in a bovine in vitro model. ROS fluorescent intensity in mature oocytes was significantly lower in the lycopene group, and resulting embryos showed a significantly higher blastocyst rate on day 8 and lower apoptotic cell ratio than all other groups. Transcriptomic analysis disclosed a total of 296 differentially expressed genes (Benjamin-Hochberg adjusted P < 0.05 and = 1 log2 fold change) between lycopene and control groups with pathways associated with cellular function, metabolism, DNA repair, and anti-apoptosis upregulated in lycopene. Lycopene supplementation in serum-free maturation medium neutralizes excess ROS during maturation, enhances blastocyst development and quality, and modulates the transcriptomic landscape. Overall design: We hypothesized that supplementation of antioxidants in a serum-free maturation medium would be effective in obtaining optimal ROS neutralization and maintenance of equilibrium during IVM and embryo development. This study aimed to assess if lycopene supplementation in serum-free maturation medium reduces ROS generation in matured oocytes and improves subsequent embryo development, quality, transcriptomic profile, and whether lycopene supplementation during maturation exerted extended protective actions on vitrified-warmed embryos.