Mammalian oviduct and protection against free oxygen radicals: expression of genes encoding antioxidant enzymes in human and mouse.

Genetic expression of five antioxidant enzymes involved in mechanisms protecting embryos against reactive oxygen species (ROS) was studied in human and mouse oviducts. The presence of transcripts encoding for gamma-glutamylcysteine synthetase (GCS), glutathione peroxidase (GPX), Cu-Zn-superoxide dismutase (Cu-Zn-SOD), Mn-superoxide dismutase (Mn-SOD) and catalase was analysed by use of the reverse transcription-polymerase chain reaction (RT-PCR). Different expression profiles of transcripts encoding for these enzymes were observed between human and mouse oviducts. In the mouse, all transcripts encoding for the enzymes tested were present in oviduct. In human, only transcripts encoding for GPX, Cu-Zn-SOD and catalase were also detected in oviduct. However, GCS and Mn-SOD transcripts were never observed in human oviduct. Cu-Zn-SOD transcripts are relatively highly expressed whatever species. These results suggest that different gene expression patterns of these antioxidant enzymes between human and mouse may reflect the variations in the ability of embryos to develop in vivo and in vitro. However, hormone related-expression of the missing transcripts in human cannot be ruled out.