Diabetic Nephropathy-associated MicroRNA Expression Profiles And Studies On The Polymorphism Of The Promoter Region Of Let-7a Gene Promoter

Objective Using bioinformatics methods to evaluate miRNAexpression patterns in type2diabetes (DM); Using miRNA microarrayassay to establish an circulating miRNAs expression profile in diabeticnephropathy patients (DN), compare to the miRNAs expression in type2diabetes. To explore the dysregulated expressed miRNAs both in type2diabetes and diabetic nephropathy.Methods Microarray datasets were downloaded from GeneExpression Omnibus (GEO) database. Microarray datasets analysis wasperformed using the software TIGR MultiExperiment Viewer(MEV:version4.9). SAM statistical analysis was used to comupete genefold change. miRNAs which showed dysregulated expression in theintegrated datasets were identified; microRNA microarray assays wereperformed in DM and DN patients to identify differential expressedmiRNAs; Real-time PCR was carried out to detect the expression level oflet-7a in the case and control groups.Results We identified18aberrant miRNAs based on previous DMmicroarray datasets, which we compared with miRNA microarray assayresults. One of the differentially expressed microRNAs, let-7a, was foundto be down-expressed in DN. Quantitative RT-PCR validated the let-7aexpression levels which was consistent with expression profile results.Conclusion The establishment of miRNA expression profile in diabetes and diabetic nephropathy may provide new ideas for the early moleculardiagnosis and treatment. One of the differentially expressed microRNAs,let-7a, may be a potential candidate miRNA involved in the susceptibilityto DN. Objective To explore the relationship between the circulating miRNAlet-7a and diabetic nephropathy, to analyze and evaluate let-7a regulatoryregion polymorphisms and their susceptibility to DN disease.Methods Bioinformatics methods were used to predict and filter outthree tag SNPs in let-7a gene promoter regulatory region, Polymerase chainreaction-restriction fragment length polymorphism (RFLP-PCR) methodwas executed genotype in108patients with diabetic nephropathy (DN),104patients with diabetes (DM) patients and62cases of healthy controls(CON).Results Real-time PCR showed that the expression level of let-7awere significantly different in DN, DM, CON three groups (P<0.05). avariant rs1143770was found in let-7a-2regulatory region and thedistributions of CT genotypes were significantly different in threegroups(P<0.05), and the CT+TT genotypes frequencies were significantlyhigher in DM and DN groups than that in CON group(P=0.049, P=0.001).Conclusion Let-7a-2might participate in the regulation of theoccurrence of DN, and a potential variant rs1143770in let-7a-2regulatoryregion was significantly associated with the increased risk for DN.