Objectives: The deficiency of liver regeneration needs to be addressed in the fields of liver surgery, split liver transplantation and living donor liver transplantation. Researches of microRNAs would broad our understandings on various diseases mechanisms. Our previous research has confirmed that miR-26a regulated liver regeneration in mice, however, the relationship between miR-26a and its target, directly or indirectly, is remaily unclearly. Therefore, we further investigated the detailed mechanism of miR-26a regulating mouse hepatocyte proliferation in the current study.

Methods: In vitro, an established mouse liver cell line, Nctc-1469, was transfected with Ad5-miR-26a-EGFP, Ad5-anti-miR-26a-EGFP or Ad5-EGFP vector, and cell proliferation by MTS, cell apoptosis and cell cycle by flow cytometry, and gene expression by western blot and quantitative real-time PCR were assessed, and dual-luciferase reporter assays were used to test targets of miR-26a.

Results: Our results showed that down-regulation of miR-26a increased proliferation of hepatocytes, with more cells entering G1 phase of cell cycle (82.7 ± 1.45% vs. 75.8 ± 3.92%), and decreased apoptosis (5.50 ± 0.35% vs. 6.73 ± 0.42%) compared with Ad5-EGFP group in vitro, CCND2 and CCNE2 were the direct targeted genes of miR-26a, and their expressions were up-regulated as well as p53 expression was down-regulated in miR-26a downregulated cells. On the contrary, miR-26a over-expression showed converse results.

Conclusions: This study demonstrated that miR-26a regulated mouse hepatocyte proliferation by directly targetedtheir 3′ untranslated regions of Cyclin E2/Cyclin D2, and simultaneously regulated p53-mediated apoptosis. It is suggested that miR-26a can be a promising regulator in liver regeneration.

« Back to 2015 American Transplant Congress