富硒地区山羊组织中的硒沉积量及其对PHGPx表达的影响

Se deposition and its effect on mRNA expression of PHGPx in some tissues of goat in Se-rich area

【目的】检测富硒地区山羊部分组织中的硒沉积量,分析组织硒沉积量对磷脂氢谷胱甘肽过氧化物酶(Phospholipid hydroperoxide glutathione peroxidase,PHGPx)基因表达的影响。【方法】将年龄相仿、体质量相近,分别来自富硒地区陕西紫阳县双安镇(试验Ⅰ组)、高滩镇(试验Ⅱ组)的山羊作为研究对象,以硒水平正常的宝鸡市陈仓区的山羊作为对照,采集各组山羊血液,分离血清,然后采用切断颈动脉放血法屠宰,随后立即采集心脏、肝脏、脾脏、肺脏、肾脏、背最长肌、股二头肌以及羊毛组织样,利用氢化物发生-原子荧光光谱法测定样品中的硒含量;运用实时荧光定量PCR(qRT-PCR)技术检测心脏、肝脏、脾脏、肺脏、肾脏、背最长肌、股二头肌组织中PHGPx基因mRNA的表达量,分析硒沉积量对PHGPx基因mRNA表达的影响。【结果】Ⅰ组山羊,除肾脏中的硒含量显著高于对照组(P<0.05)外,其他组织均极显著高于对照组(P<0.01);Ⅱ组山羊,心脏、肝脏、脾脏、羊毛和血清中硒含量极显著高于对照组(P<0.01),背最长肌和股二头肌中的硒含量显著高于对照组(P<0.05),肺脏、肾脏与对照组差异不显著(P>0.05)。PHGPx基因mRNA在Ⅰ组山羊各组织中的表达量由高到低依次为肺脏>股二头肌>脾脏>肾脏>心脏>背最长肌>肝脏;在Ⅱ组为肺脏>股二头肌>脾脏>肝脏>肾脏>心脏>背最长肌。与对照组相比,Ⅰ组山羊心脏中PHGPx基因mRNA的表达量显著升高(P<0.05),肺脏极显著升高(P<0.01);试验Ⅱ组山羊肝脏中PHGPx基因mRNA的表达量显著高于试验Ⅰ组和对照组(P<0.05)。试验Ⅰ组、Ⅱ组、对照组山羊脾脏、肾脏、背最长肌和股二头肌中PHGPx基因mRNA的表达量差异不明显。【结论】富硒地区山羊各组织中硒沉积量和PHGPx基因mRNA表达水平总体上高于宝鸡市陈仓地区山羊,而且山羊心脏、肝脏、肺脏中PHGPx基因mRNA的表达量受到其硒元素沉积量的影响,这表明硒在转录水平上可调控PHGPx基因的表达,但是具有组织差异性。

【Objective】This study intended to detect the deposition levels of Se(selenium)and its effect on mRNA expression of phospholipid hydroperoxide glutathione peroxidase(PHGPx)gene in some tissues of goat from Ziyang County,a selenium-rich region in China.【Method】Goats with similar ages and weights from Shuang'an Town(groupⅠ),Gaotan Town(groupⅡ)of Ziyang County and Chencang Dis-trict of Baoji City(control group)were chosen.Then atomic fluorescence spectrometry was used to determinate Se concentrations in heart,liver,spleen,lung,kidney,longissimus,biceps femoris,fleece and serum.At the same time,real-time quantitative PCR(qRT-PCR)was used to detect the relative mRNA expression levels of PHGPxin heart,liver,spleen,lung,kidney,longissimus muscle,and biceps femoris.【Result】Se concentration in kidney of group Ⅰ was significantly higher than that in control group(P<0.05)and the concentrations in other tissues were very significantly higher(P<0.01).Se concentrations in heart,liver,spleen,fleece and serum of group Ⅱ were also very significantly higher than that in control group(P<0.01),concentrations in longissimus muscle and biceps femoris were significantly higher(P<0.05),while the differences in lung and kidney were not significant(P>0.05).The mRNA levels of PHGPx were in a decreasing order of lung>biceps femoris>spleen>kidney>heart>longissimus muscle>liver in groupⅠ,while in a decreasing order of lung>biceps femoris>spleen>liver>kidney>heart>longissimus muscle in group Ⅱ.Compared with control group,the mRNA levels of PHGPxin heart of groupⅠ were significantly higher(P<0.05),and in lung were very significantly higher(P<0.01).The mRNA levels of PHGPx in liver of group Ⅱ were significantly higher than group Ⅰ and control group(P<0.05).However,there were no significant differences in mRNA levels of PHGPxin spleen,kidney,longissimus muscle and biceps femoris among the three groups.【Conclusion】Se concentrations and mRNA levels of PHGPxin various tissues of goat from Se-rich area were both higher than that of goat from Chencang District,Baoji,and the expression levels of PHGPx were up-regulated by the deposition of Se in heart,liver and lung of goats.Therefore,it was concluded that Se regulated the mRNA expression of PHGPx,and the regulation was different among tissues.