ABSTRACT
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 with 30 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 Pearson correlation analysis,respectively.Results The selenium contents in the plasma (P＜0.0001)and whole blood (P＜0.001)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 2 1 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.