Beauvericin alters the expression of genes coding for key proteins of the mitochondrial chain in ovine cumulus-oocyte complexes

In this study, the effects of BEA at 0.5, 1, ,3 and 5 μmol/L on expression of genes coding for key proteins of the mitochondrial chain in ovine oocytes and cumulus cells were evaluated at different time points of in vitro maturation (IVM), germinal vesicle (GV;t = 0), metaphase I (MI;t = 7 h), and metaphase II (MII;t = 24 h). The expression of nuclear (TFAM,NDUFA12,UQCRH,COX4,ATP5O) and mitochondrial (ND1,COX1,COX2,ATP6,ATP8) genes coding for proteins of Complexes I, III, IV, and V was analyzed by qRT-PCR. After BEA exposure, perturbed expression of all genes was observed in cumulus cells and in oocytes at the MI stage (7 h IVM). Expression ofND1,UQCRH,COX4 andATP5O was downregulated in cumulus cells and upregulated in oocytes starting from 0.5 μmol/L BEA. Expression ofTFAM,NDUFA12,COX1,COX2,ATP6, andATP8 was upregulated starting from 1 μmol/L in cumulus cells and from 3 μmol/L in oocytes. Cumulus cells and oocytes displayed different gene expression patterns upon BEA exposure. The downregulation in cumulus cells of four genes coding for proteins of mitochondrial complexes could represent a major toxic event induced by BEA on the cumulus-oocyte complex which may result in mitochondrial functional alteration.

Source: Mycotoxin Research - September 25, 2020 Category: Toxicology Source Type: research