Isobutylparaben Negatively Affects Porcine Oocyte Maturation Through Increasing Oxidative Stress and Cytoskeletal Abnormalities

As a member of parabens (PBs), Isobutylparaben (IBP) has a broad-spectrum antimicrobial activity and widely used in personal care products and cosmetics. Recent studies have indicated that usage of IBP poses a potential threat to reproductive health. In this study, we aimed to reveal the effects of acute exposure to IBP on the meiotic maturation of porcine cumulus oocyte complexes. Initial study showed that 200 mu M of IBP significantly reduced the rate of the first polar body extrusion with no significant effect on cumulus cell expansion; however, 400 mu M of IBP could significantly affect both. Further research revealed that abnormal spindles, misalignment chromosomes, and aberrant distributed actin filaments were detected in IBP-treated oocytes, which indicates that the cytoskeleton architecture of oocyte could be the target of IBP. At the same time, ROS level and apoptosis rate of oocyte were significantly increased by IBP exposure. Moreover, the levels of H3K9me3 and H3K27me3 were significantly induced in oocytes by IBP. Collectively, these results demonstrate that acute exposure to IBP could disrupt porcine oocyte maturation through affecting cytoskeleton, oxidative stress, viability and epigenetic modification. Environ. Mol. Mutagen. 2020. (c) 2020 Wiley Periodicals, Inc.