P-317 - Preparation of selenium-deficient mouse model and its glutathione peroxidase activity

Abstract

Relatively young (8-week-old) selenium deficient (SeD) mouse model was prepared using SeD diet. Selenium (Se), which is an essential trace element, has important roles in the biological redox regulation system as the catalytic center of glutathione peroxidases (GSH-Px). Mice were fed on torula yeast based SeD diet (F2SeDD, Oriental Yeast Co., Ltd., Tokyo) and ultra-pure water (mili-Q water). Several different timings for starting SeD diet were demonstrated and weekly time course of liver GSH-Px activities after starting SeD diet were monitored. Postweaning (4-week-old or older) start of SeD diet gives relatively older (> 8-week-old) SeD mice. The same procedure which was reported for a Se-deficient rat model (Matsumoto et al., Biol. Pharm. Bull. 23, 641–644, 2000.) could not prepared Se-deficient mouse model due to neonatal death. Starting SeD diet to the mother mouse from 2 weeks after giving birth could give 8-week-old SeD mouse model (SeD-trial-2w). Tissue GSH-Px activities of 8-week-old SeD-trial-2w group were almost non, while the normal group (fed on normal diet, MB-1) and SeC group (fed on SeD diet+1.5 mg Se in drinking water) could keep GSH-Px activity. This SeD-trial-2w mouse model can be proposed for an H2O2-induced oxidative stress model for future experiments.