EFFECTS OF DIETARY SELENIUM AND VITAMIN-E CONCENTRATIONS ON PHOSPHOLIPID HYDROPEROXIDE GLUTATHIONE-PEROXIDASE EXPRESSION IN REPRODUCTIVE TISSUES OF PUBERTAL MATURING MALE RATS

Phospholipid hydroperoxide glutathione peroxidase (PHGPX) is the secon d intracellular selenium (Se)-dependent glutathione peroxidase (GSH-Px ) identified in mammals. Our objectives were to determine the effect o f dietary vitamin E and Se levels on PHGPX activity expression in test is, epididymis, and seminal vesicles of pubertal maturing rats, and th e relationship of PHGPX expression with testicular development and spe rm quality. Forty Sprague-Dawley male weanling rats (21-d old), were i nitially fed for 3 wk a torula yeast basal diet (containing 0.05 mg Se /kg) supplemented with marginal levels of Se(0.1 mg/kg as Na2SeO3) and vitamin E (25 IU/kg as all-rac-alpha-tocopheryl acetate). Then, rats were fed the basal diets supplemented with 0 or 0.2 mg Se/kg and 0 or 100 IU vitamin E/kg diet during the 3-wk period of pubertal maturing. Compared with the Se-supplemented rats, those fed the Se-deficient die ts retained 31, 88, 67, and 50% of Se-dependent GSH-Px activities in L iver, testis, epididymis, and seminal vesicles, respectively. Testes a nd seminal vesicles had substantially higher (5- to 20-fold) PHGPX act ivity than Liver. Dietary Sc deficiency did not affect PHGPX activitie s in the reproductive tissues, but reduced PHGPX activity in Liver by 28% (P < 0.0001). Dietary vitamin E supplementation did not affect PHG PX activity in liver, whereas it raised PHGPX activity in seminal vesi cles by 43% (P < 0.005). Neither dietary vitamin E nor Se levels affec ted body weight gains, reproductive organ weights, or sperm counts and morphology. In conclusion, expression of PHGPX activity in testis and seminal vesicles was high and regulated by dietary Se and vitamin E d ifferently from that in liver.