Zhou Ji-Chang, Zheng Shijie, Mo Junluan, Liang Xiongshun, Xu Yuanfei, Zhang Huimin, Gong Chunmei, Liu Xiao-Li, Lei Xin Gen
Molecular Biology Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen Guangdong, China;
Molecular Biology Laboratory, Shenzhen Center for Chronic Disease Control, Shenzhen Guangdong, China.
J Nutr. 2017 Oct;147(10):1947-1953. doi: 10.3945/jn.117.252544. Epub 2017 Aug 16.
Glutathione peroxidase (GPX) 4 and selenoprotein P (SELENOP) are abundant, and several variants are expressed in the testis. We determined the effects of dietary selenium deficiency or excess on sperm quality and expressions of GPX4 and SELENOP variants in rat testis and liver. After weaning, male Sprague-Dawley rats were fed a Se-deficient basal diet (BD) for 5 wk until they were 9 wk old [mean ± SEM body weight (BW) = 256 ± 5 g]. They were then fed the BD diet alone (deficient) or with 0.25 (adequate), 3 (excess), or 5 (excess) mg Se/kg for 4 wk. Testis, liver, blood, and semen were collected to assay for selenoprotein mRNA and protein abundances, selenium concentration, GPX activity, 8-hydroxy-deoxyguanosine concentration, and sperm quality. Dietary selenium supplementations elevated ( < 0.05) tissue selenium concentrations and GPX activities. Compared with those fed BD + 0.25 mg Se/kg, rats fed BD showed lower ( < 0.05) BW gain (86%) and sperm density (57%) but higher ( < 0.05) plasma 8-hydroxy-deoxyguanosine concentrations (189%), and nonprogressive sperm motility (4.4-fold). Likewise, rats fed BD + 5 mg Se/kg had ( = 0.06) lower BW gain and higher (1.9-fold) sperm deformity rates than those in the selenium-adequate group. Compared with the selenium-adequate group, dietary selenium deficiency (BD) or excess (BD + 3 or 5 mg Se/kg) resulted in 45-77% lower ( < 0.05) nuclear () mRNA abundance in the testis. Rats fed BD had lower ( < 0.05) mRNA levels of 2 variants in both testis and liver than those in the other groups. Testicular SELENOP was 155-170% higher ( < 0.05) in rats fed BD + 5 mg Se/kg and hepatic c/mGPX4 was 13-15% lower ( < 0.05) in rats fed BD than in the other groups. The mRNA abundance of rat testicular nGPX4 responded to dietary selenium concentrations in similar ways to sperm parameters and may be used as a sensitive marker to assess appropriate Se status for male function.
谷胱甘肽过氧化物酶（GPX）4和硒蛋白P（SELENOP）含量丰富，且有多种变体在睾丸中表达。我们测定了饮食中硒缺乏或过量对大鼠睾丸和肝脏中精子质量以及GPX4和SELENOP变体表达的影响。断奶后，雄性Sprague-Dawley大鼠喂食缺硒基础日粮（BD）5周，直至9周龄[平均±标准误体重（BW）=256±5克]。然后，它们单独喂食BD日粮（缺硒组）或添加0.25（适量）、3（过量）或5（过量）毫克硒/千克的BD日粮，持续4周。收集睾丸、肝脏、血液和精液，检测硒蛋白mRNA和蛋白质丰度、硒浓度、GPX活性、8-羟基脱氧鸟苷浓度以及精子质量。饮食中补充硒可提高（<0.05）组织硒浓度和GPX活性。与喂食BD + 0.25毫克硒/千克的大鼠相比，喂食BD的大鼠体重增加（86%）和精子密度（57%）较低，但血浆8-羟基脱氧鸟苷浓度（189%）和非进行性精子活力（4.4倍）较高。同样，与硒适量组相比，喂食BD + 5毫克硒/千克的大鼠体重增加较低（=0.06），精子畸形率较高（1.9倍）。与硒适量组相比，饮食中硒缺乏（BD）或过量（BD + 3或5毫克硒/千克）导致睾丸中核（）mRNA丰度降低45 - 77%（<0.05）。喂食BD的大鼠睾丸和肝脏中2种变体的mRNA水平均低于其他组（<0.05）。与其他组相比，喂食BD + 5毫克硒/千克的大鼠睾丸SELENOP高155 - 170%（<0.05），喂食BD的大鼠肝脏c/mGPX4低13 - 15%（<0.05）。大鼠睾丸nGPX4的mRNA丰度对饮食中硒浓度的反应与精子参数相似，可作为评估雄性功能适宜硒状态的敏感标志物。
