硒元素及硒蛋白在糖尿病肾病中的表达变化

Changes of selenium and selenoprotein expressions in diabetic nephropathy

目的检测糖尿病肾病(DN)患者血浆及全血中硒元素含量,以及高糖条件下人肾小球系膜细胞中硒蛋白的表达变化,探究硒与DN的关系。方法收集正常对照及DN患者全血及血浆,用原子吸收光谱法检测血浆和全血中的硒元素含量;用30mmol/L的高糖刺激人肾小球系膜细胞,实时定量PCR检测人类硒蛋白表达谱的变化;非配对t检验和Pearson相关分析检验组间差异及指标间的相关关系。结果 DN患者血浆(P<0.000 1)及全血(P<0.001)中的硒含量与对照组相比均显著降低。患者血浆硒含量与血尿素氮及血肌酐水平呈负相关(r=-0.368、-0.413),与糖化血红蛋白水平也呈负相关(r=-0.400)。人肾小球系膜细胞在高糖刺激24h后硒蛋白Gpx1、TrxR2、TrxR3、Dio2、Dio3、SelK、SelN、SelP、SelR、SelT、SelW、SPS2的表达显著降低,初步筛选出了有表达差异的硒蛋白。结论DN患者体内存在明显低硒状态,高糖环境下人肾小球系膜细胞一些硒蛋白的表达显著降低,为阐明低硒敏感的硒蛋白在DN发生发展中的作用提供了临床和实验依据。

Objective To explore the relationship between selenium and diabetic nephropathy（DN）by determining the selenium content in the plasma and whole blood of DN patients and the changes of selenoprotein expressions in human mesangial cells stimulated by high glucose.Methods We collected the samples and clinical indicators of DN patients and healthy controls to determine selenium content by atomic absorption spectrometry method.The mRNA in human mesangial cells was isolated after stimulation with30 mmol/L of glucose for 24 hours by Trizol method to detect the changes of selenoprotein expressions by Real-time PCR.We analyzed the differences between DN patients and healthy controls and the relationship between clinical indicators by unpaired t-test and Pearsoncorrelation analysis,respectively.Results The selenium contents in the plasma（P0.0001）and whole blood（P0.001）were significantly lower in DN patients than in the healthy controls.In addition,plasma selenium contents had a significant negative correlation with renal function and a positive correlation with glycosylated hemoglobin in DN patients.Among the 21 human selenoproteins,the mRNAs of Gpx1,TrxR2,TrxR3,Dio2,Dio3,SelK,SelN,SelP,SelR,SelT,SelW and SPS2 were significantly lower in the high-glucose group than in the normal-glucose group which produced by human mesangial cells after high glucose stimulation for 24 hours.Conclusion There was obvious selenium deficiency in DN patients.Human mesangial cells have a significantly low expression of some selenoproteins in the high glucose environment.These results provide clinical and experimental evidence for illuminating the role of low selenium-sensitive selenoproteins in the occurrence and development of DN.