Intracellular glutathione content, developmental competence and expression of apoptosis-related genes associated with G6PDH-activity in goat oocyte

To associate glucose-6-phosphate dehydrogenase (G6PDH) activity in goat oocytes with intracellular glutathione (GSH) content, meiotic competence, developmental potential, and relative abundance of Bax and Bcl-2 genes transcripts.Purpose To associate the glucose-6-phosphate dehydrogenase (G6PDH) activity inimmature goat oocyte with intracellular glutathione (GSH) content, developmentalcompetence after parthenogenetic activation and relative abundance of Bax and Bcl-2genes transcripts using .Methods Goat oocytes were exposed to brilliant cresyl blue (BCB) staining andcategorized into BCB+ (blue cytoplasm) and BCB&minus; (colorless cytoplasm) groups. Agroup of oocytes were not exposed to BCB stain and was considered as a control.After maturation in vitro, a group of oocytes were used for determination of nuclearstatus and intracellular GSH content and another group were subjected toparthenogenetic activation followed by in vitro embryo culture.Results We found that BCB+ oocytes yielded a significantly higher maturation rate thanthe BCB&minus; and control oocytes. Moreover, BCB+ oocytes showed increased inintracellular level of GSH than BCB&minus; and control oocytes. Furthermore, BCB+ oocytesproduced more blastocysts than BCB&minus; and control oocytes. The expression of antiapoptoticgene Bcl-2 and pro-apoptotic gene Bax in mature oocyte, their surroundingcumulus cells and blastocyst was affected by BCB staining test.Conclusions These results strongly suggest that BCB+ oocytes have a higher meioticand cytoplasmic maturity (as determined by intracellular GSH content), and that BCBstaining can be used to select developmentally competent oocytes for in vitro embryoproduction.</p