Effects of dietary Se deficiency or excess on gene expression of 13 novel selenoproteins in growing pigs

Abstract

We previously reported effects of dietary Se concentrations on gene expression of 12 selenoproteins in porcine tissues. This study was to determine responses of tissue mRNA levels for the rest of 13 out of 25 porcine selenoprotein genes to dietary Se deficiency and excess. Weanling male pigs (n = 30) were fed a corn (from Se‐deficient area)‐soy basal diet (0.02 mg Se/kg) supplemented with 0, 0.3, or 3.0 mg Se/kg as Se‐enriched yeast (Angel Yeast, Hubei, China) for 16 wk. In the end, samples of 11 different tissues were collected for relative mRNA level analyses using Real‐Time RT‐PCR. Compared with the Se‐supplemented pigs, the Se‐deficient pigs showed lower (P < 0.05) mRNA level of gpx1, gpx3, selpp1, selS in blood and several tissues. In contrast, dietary Se deficiency enhanced (P < 0.05) mRNA levels of sps2, selI, selO, selT and selV in various tissues. Pigs fed 0.3 mg Se/kg had greater (P < 0.05) mRNA levels of sel15, sps2, selH, selI, selM and selV in thyroid, spleen, or pituitary than those of the other two groups. The relative mRNA levels of selS and gpx1 in thyroid and selH and selI in pituitary were lower (P < 0.05) in pigs fed the Se‐deficient diet than those fed 0.3 mg Se/kg. In conclusion, the effects of dietary Se deficiency or excess on the gene expression of the 13 novel porcine selenoproteins in various tissues were non‐unilateral. (NSFC Projects 30628019, 30700585, and 30871844, and the Chang Jiang Scholars Program).