Assessment of some mitochondrial function based on gene expression in sow oocyte cultured in vitro

Abstract

Oocyte maturation represents the highlight of developmental process in the ovarian follicle. It entirely depends on mitochondrial ability to ensure energy supplies. Beside ATP production, mitochondria is involved in apoptosis and any disorder generating ROS excess will lead to cellular death. Using PCR reaction we have assessed the gene expression for proapoptotic (Bax), antiapoptotic (Bcl2 and p53) and mitochondrial-related genes (Polg, Polg2 and CYTB) in sow oocyte cultured in vitro. Oocyte-cumulus complexes were cultured in TCM media supplemented with PMSG and HCG (group A -control) plus 0.57 Mm cysteine (group B) or 10 μg/ml quercetin (group C). Based on their antioxidative properties, the added compounds generated a satisfactory oocyte maturation rate without any gene inhibition, except group C. The over-expression of POLG and Polg2 genes accompanied by an increase of gene expression involved in apoptosis and all of these correlated with an increase of Bax/Bcl2 ratio determined us to conclude that culture media supplementation with 10 μg/ml of quercetin is not suitable for in vitro sow oocyte maturation.