Mouse Liver Regeneration

The goal of this study is to obtain an expression profile of regenerating mouse livers. We used microarray analysis to study the gene groups coordinately expressed temporally during mouse a liver regeneration. One of the syn-expression groups that showed a sharp rise in gene expression immediately after hepatectomy contains a set pancreatic exocrine genes. The syn-expression profile of pancreatic genes and the pancreatic-specific transcription factors Ptf1a and Ipf1 was confirmed using real-time PCR. Electron microscopic examination showed the presence of morphological features reminiscent of pancreatic acinar cells with the presence of characteristic zymogen granules and ER organization. These results indicate that there is a transient liver-to-pancreas transdifferentiation event at the beginning of liver regeneration. A strong coordinated up-regulation of pancreatic genes was found to accompany the injury response in the pancreas, suggesting a compensatory mechanism for pancreatic functions. There seems to be a relationship between the induction of pancreatic genes and acute phase response at the beginning of liver regeneration. Keywords: gene expression array-based (RNA / in situ oligonucleotide) Total RNA was extracted from livers of mice recovered at various hours after partial hepatectomy (PHx 4h, 8h, 12h, 36h, 48h, 72h). We grouped livers of four to six mice together for RNA extraction. Genes showed differentially up- or downregulated by two-fold with respect to the normal mouse livers were identified using GeneSpring software version 7.2 (Silicon Genetics, Agilent Technologies).