MicroRNA profiling in murine liver after partial hepatectomy.
Liver is uniquely capable to repair itself after injury. Multiple molecular             and biochemical processes initiated after partial hepatectomy, lead to proliferation             of all cells within the liver. MicroRNAs (miRNAs) are a class of highly abundant             non-coding RNA molecules that cause post-transcriptional gene repression and are             involved in several biological processes including cell cycle regulation and differentiation.             In this study, we examined the expression levels of miRNAs in liver tissue received             from control mice (L0) and compared them with the corresponding levels in liver             tissue 12 h after liver regeneration induced by 2/3 partial hepatectomy (L12).             MiRNA expression was investigated using microRNA profiling. Further qPCR analysis             was used for validation of the differentially expressed miRNAs at an early stage             of liver regeneration, induced by 2/3 partial hepatectomy. TargetScan and Gene             Ontology (GO) analyses were performed in order to identify the possible miRNA             target genes and their ontology, respectively. A subset of miRNAs was found to             be differentially expressed during liver regeneration. Mmu-miR-21 and mmu-miR-30b*             showed the higher levels of up-regulation in liver tissue from the hepatectomized             mice at the end of the experiment (L12) compared to the sham operated mice (L0).             Mmu-miR-21 up-regulation was further confirmed by qPCR. In situ hybridization             (ISH) revealed that mmu-miR-21 exhibited the higher levels of expression at 12             h post hepatectomy. On the contrary, mmu-miR-34c*, mmu-miR-144, mmu-miR-207, mmu-miR-207,             mmu-miR-451, mmu-miR-582-3p and mmu-miR-290-5p exhibited <0.5 down-regulation             in liver tissue after partial hepatectomy in L12 vs. L0 mice. The results from             microarray and qPCR analyses were in good agreement. In conclusion, our results             provide important information regarding the differentially expressed miRNAs in             murine liver tissue before and after partial hepatectomy. The early up-regulation             of mmu-miR-21 during the process of liver regeneration suggests a regulatory role             in liver regeneration in vivo.
Surgical Department, Medical School, University of Patras, 26504                     Patras, Greece.
Ioannis
I
Chaveles
Apostolos
A
Zaravinos
Ioannis G
IG
Habeos
Dimitrios D
DD
Karavias
Ioannis
I
Maroulis
Demetrios A
DA
Spandidos
Dionisios
D
Karavias
D000818:Animals; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006498:Hepatectomy; D008099:Liver / Q000378:metabolism / Q000502:physiology*; D008115:Liver Regeneration; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D035683:MicroRNAs / Q000235:genetics*
C000599184:MIRN207 microRNA, mouse; C531950:MIRN21 microRNA, mouse; D035683:MicroRNAs