MicroRNA array analysis during the regenerative peak following rat liver resection

The liver has the unique capacity to regenerate after surgical resection. However, the regulation of liver regeneration is not completely understood. We performed miRNA microarray analyses of liver tissue from Wistar rats at different time points after 70% partial hepatectomy (0, 2, 6, 12, 24, 48 hours, and 5 days) and after sham laparotomy (12, 24, and 48 hours). We demonstrate that miRNA expression patterns changed during liver regeneration and that these changes were most evident during the peak of DNA replication at 24 hours after resection. Expression of 13 miRNAs, including five members of the let-7 family, was significantly reduced 12-48 hours after resection, whereas 3 miRNAs were significantly upregulated (> 25% change). We provide a temporal miRNA expression dataset of the regenerating rat liver, which indicates a primary function for miRNA during the peak of DNA replication. These data will assist further functional studies on the role of miRNAs during liver regeneration. This project analyzed the miRNA expression in 30 different sample types of the organism rattus norvegicus. The miRNA expression was compared at 7 different growth time points after liver resection (0, 2, 6, 12, 24, 48 hours, 5 days) and at 3 different time points after sham laparotomy (12, 24, and 48 hours). Three biological replicates were used per time point.