Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2015; 21(34): 9900-9915
Published online Sep 14, 2015. doi: 10.3748/wjg.v21.i34.9900
MiR-9a-5p regulates proliferation and migration of hepatic stellate cells under pressure through inhibition of Sirt1
Feng Qi, Jiang-Feng Hu, Bao-Hai Liu, Chao-Qun Wu, Hong-Yu Yu, Ding-Kang Yao, Liang Zhu
Feng Qi, Bao-Hai Liu, Hong-Yu Yu, Ding-Kang Yao, Liang Zhu, Department of Gastroenterology, Changzheng Hospital, the Second Military Medical University, Shanghai 200003, China
Jiang-Feng Hu, Department of Gastroenterology, Institute of Digestive Diseases, Tongji Hospital, Tongji University, Shanghai 200065, China
Chao-Qun Wu, Genetics Institute, Fudan University, Shanghai 200433, China
Author contributions: Qi F and Hu JF performed the majority of experiments; Liu BH, Wu CQ, Yu HY, Yao DK and Zhu L provided vital reagents and analytical tools and were also involved in editing the manuscript; Qi F designed the study and wrote the manuscript.
Supported by National Natural Science Foundation of China, No. 11272342/A0205.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Committee on the Ethics of Animal Experiments of the Second Military Medical University animal center (protocol number: 13071002107).
Conflict-of-interest statement: The authors declare that they have no competing interests.
Data sharing statement: Dataset available from the corresponding author at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE63783.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Liang Zhu, Professor, Department of Gastroenterology, Changzheng Hospital, the Second Military Medical University, No. 415 Fengyang Road, Shanghai 200003, China. zhuliangcz@126.com
Telephone: +86-21-81885261
Received: February 26, 2015
Peer-review started: February 27, 2015
First decision: March 26, 2015
Revised: April 11, 2015
Accepted: July 3, 2015
Article in press: July 3, 2015
Published online: September 14, 2015
Abstract

AIM: To reveal the functions of microRNAs (miRNAs) with respect to hepatic stellate cells (HSCs) in response to portal hypertension.

METHODS: Primary rat HSCs were exposed to static water pressure (10 mmHg, 1 h) and the pressure-induced miRNA expression profile was detected by next-generation sequencing. Quantitative real-time polymerase chain reaction was used to verify the expression of miRNAs. A potential target of MiR-9a-5p was measured by a luciferase reporter assay and Western blot. CCK-8 assay and Transwell assay were used to detect the proliferation and migration of HSCs under pressure.

RESULTS: According to the profile, the expression of miR-9a-5p was further confirmed to be significantly increased after pressure overload in HSCs (3.70 ± 0.61 vs 0.97 ± 0.15, P = 0.0226), which resulted in the proliferation, migration and activation of HSCs. In vivo, the up-regulation of miR-9a-5p (2.09 ± 0.91 vs 4.27 ± 1.74, P = 0.0025) and the down-regulation of Sirt1 (2.41 ± 0.51 vs 1.13 ± 0.11, P = 0.0006) were observed in rat fibrotic liver with portal hypertension. Sirt1 was a potential target gene of miR-9a-5p. Through restoring the expression of Sirt1 in miR-9a-5p transfected HSCs on pressure overload, we found that overexpression of Sirt1 could partially abrogate the miR-9a-5p mediated suppression of the proliferation, migration and activation of HSCs.

CONCLUSION: Our results suggest that during liver fibrosis, portal hypertension may induce the proliferation, migration and activation of HSCs through the up-regulation of miR-9a-5p, which targets Sirt1.

Keywords: MicroRNA, miR-9a-5p, Sirt1, Pressure, Hepatic stellate cells

Core tip: Portal hypertension is a syndrome as the main characteristics of the portal system hemodynamics change. Hepatic stellate cell (HSC) activation is the key factor of promoting the development of the occurrence of liver cirrhosis and portal hypertension. We determined the levels of miR-9a-5p in HSCs under pressure. We found that higher levels of miR-9a-5p, which targeted Sirt1, were expressed in vivo. The restored expression of miR-9a-5p and Sirt1 could significantly suppress the proliferation, migration and activation of HSCs.