Smart RNA Sequencing Reveals the Toxicological Effects of Diisobutyl Phthalate (DiBP) in Porcine Oocytes

Diisobutyl phthalate (DiBP) is commonly
used in the plastics
industry,
and recent studies have shown that environmental exposure and accumulation
in the food chain caused inflammation in some organs. However, the
underlying mechanisms by which DiBP affects oocyte quality have not
yet been fully defined. We used immunostaining and fluorescence to
evaluate the effects of DiBP exposure and demonstrated that it impaired
the morphology of matured porcine oocytes through generation of cytoplasmic
fragmentation, accompanied by the perturbed dynamics of the spindle
and actin cytoskeleton, misdistributed endoplasmic reticulum, as well
as partial exocytosis of cortical granules and ovastacin. Moreover,
analysis of Smart RNA-seq found that DiBP-induced aberrant oocyte
maturation could be induced by abnormal mitochondrial function and
apoptosis. Importantly, we discovered that supplementation with pyrroloquinoline
quinone (PQQ) significantly attenuated the meiotic abnormalities induced
by DiBP exposure through the modulation of reactive oxygen species
levels. Our findings demonstrated that DiBP exposure adversely affects
oocyte meiotic maturation and that PQQ supplementation was an effective
strategy to protect oocyte quality against DiBP exposure.