Analysis of the phospholipid hydroperoxide glutathione peroxidase mRNA in the rat spermatozoon and effect of selenium deficiency on the mRNA

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a selenium (Se )-dependent glutathione peroxidase. It is reported that the relative PHGPx mRNA levels are much higher in the testis than in the other tissues. We hav e analyzed the existence and structure of the PHGPx mRNA in rat sperm and t he changes in the level of the PHGPx mRNA after feeding with Se-deficient d iets. We used 8-wk-old male Wistar strain rats given Se-adequate feed (cont rol group, n = 5) and Se-deficient diets with marginal levels of Se (0.03 p am or less) (Se-deficient group, n = 5) for 4 wk. The existence acid level of the PHGPx mRNA in the cauda epididymal sperm, testis, and liver from the Se-adequate rats were analyzed by the reverse transcription-polymerase cha in reaction and the Southern blotting method. As a result, the existence of the PHGPx mRNA was demonstrated in the cauda epididymal sperm as well as i n the testis and liver. Moreover, the subtype of the PHGPx mRNA in the rat sperm was the mitochondrial-type mRNA, which included a region correspondin g to the mitochondrial transfer leader sequence. These results imply that t he intracellular localization of PHGPx may be regulated by the transcriptio n level. On the other hand, there was no significant difference between the control group and the Se-deficient group in the Se level of the cauda epid idymal sperm and the level of the PHGPx mRNA. In conclusion, it has been de monstrated that the PHGPx mRNA exists in rat sperm for the first time. The analysis of the PHGPx mRNA in the sperm would be a useful tool fur investig ating the disfunction caused by the disorder of the level or structure of t he PHGPx in the sperm.