Systematic profiling of mRNA and miRNA expression in the pancreatic islets of spontaneously diabetic Goto-Kakizaki rats

Type 2 diabetes (T2DM) is a complex multifactorial metabolic disorder that affects >100 million individuals worldwide, yet the mechanisms involved in the development and progression of the disease have not yet been fully elucidated. The present study examined the mRNA and micro (mi)RNA expression profiles by microarray analysis in the pancreas islets of spontaneously diabetic Goto-Kakizaki rats with the aim to identify regulatory mechanisms underlying the pathogenesis of T2DM. A total of 9 upregulated and 10 downregulated miRNAs were identified, including miR-150, miR-497, miR-344-3p and let-7f, which were independently validated by quantitative polymerase chain reaction assays. In addition, differential expression of 670 genes was detected by mRNA microarray analysis, including 370 upregulated and 247 downregulated genes. The differentially expressed genes were statistically associated with major cellular pathways, including the immune response pathway and the extracellular matrix (ECM)-receptor interaction pathway. Finally, a reverse regulatory association of differentially expressed miRNAs and their predicted target genes was constructed, supported by analysis of their mRNA and miRNA expression profiles. A number of key pairs of miRNA-mRNA was proposed to have significant roles in the pathogenesis of T2DM rats based on bioinformatics analysis, one example being the let-7f/collagen, type II, alpha 1 pair that may regulate ECM-receptor interactions.