Analysis of underlying genes and functions associated with diabetic kidney disease

This study aimed to investigate the pathogenic characteristics of diabetic kidney disease (DKD) from gene level. The microarray data of GSE30528 and GSE30529 were downloaded to screen the differentially expressed genes (DEGs): (a) DKD glomeruli vs. normal glomeruli; (b) DKD tubuli vs. normal tubuli; (c) normal glomeruli vs. normal tubuli. Then functional enrichment analysis and interaction network analysis of the DEGs were performed. Co-expression network analysis was carried out to study the module preservation. Total 511, 503 and 941 DEGs were identified in groups a, b and c respectively. Functional enrichment analyses found that DEGs in DKD glomeruli were mainly enriched in functions related to actin cytoskeleton; in DKD tubuli were mainly enriched in immune and inflammatory response-associated functions. In the interaction networks constructed by DEGs of DKD glomeruli and DKD tubuli, FYN, FN1, RB1 and CASP3 had higher degrees. Co-expression network analysis revealed 43 modules that did not reach the threshold requirements of preservation in DKD glomeruli. The probes in 43 modules had 44 common probes with differentially expressed probes in DKD glomeruli and DKD tubuli, which were enriched in extracellular matrix-associated terms. In the interaction networks of 43 common probes, FN1, ANXA2, and EFNB2 had higher degrees. The present study indicates that the function terms like actin cytoskeleton, immune and inflammatory response and extracellular matrix may play an important role in the pathogenesis of DKD. Genes such as FN1, EFNB2 and ANXA2 may be used as novel biomarkers in DKD.