Published online Aug 21, 2019. doi: 10.3748/wjg.v25.i31.4468
Peer-review started: March 29, 2019
First decision: June 10, 2019
Revised: June 25, 2019
Accepted: July 19, 2019
Article in press: July 19, 2019
Published online: August 21, 2019
Processing time: 145 Days and 17.4 Hours
Liver fibrosis is seriously endangering the safety of life. MiRNAs are reported as key regulators of cellular differentiation and of fibrosis-suppressive functions. Different classes of miRNAs have emerged as key regulators of important hepatic stellate cell (HSC) functions, such as activation, proliferation, and epigenetic gene regulation. Therefore, miRNAs represent novel mechanisms and targets for liver fibrosis. Loss of miR-194 has been reported in activated HSCs, but the actual role of miR-194 in liver fibrosis remains uncertain.
Our findings will provide a fundamental basis for the application of miR-194 in liver fibrosis therapy.
To measure the expression of miR-194 in fibrotic liver tissues and activated HSCs, and investigate biological functions and possible molecular mechanisms of miR-194 in liver fibrosis.
We detected the expression of miR-194 in human fibrotic liver tissues, activated HSCs, and a CCl4 mouse model by qPCR. The biological behavior of miR-194 in vitro was then assessed by overexpression and knockdown of miR-194 in HSCs. In further molecular mechanism studies, we reintroduced miR-194 in mice using a miR-194 agomir to investigate the functions of miR-194 in liver fibrosis in vivo.
In the current study, we found that miR-194 was lacking in activated HSCs from both humans and mice. MiR-194 had a role of inhibiting the activation and proliferation of HSCs by suppressing AKT2. Meanwhile, we confirmed that reintroduction of miR-194 agomir through the tail vein could attenuate liver fibrosis in CCl4-treated mice in association with the reduction of AKT2. However, the specific regulatory role of miR-194 in liver fibrosis patients remains unclear, which needs to be validated in clinical studies.
MiR-194 is downregulated in activated HSCs, which could inhibit the activation and proliferation of HSCs via suppressing AKT2. Reintroduction of miR-194 exerts a protective action against liver fibrosis.
This study provides insight into the role of miR-194 in alleviating liver fibrosis by decreasing AKT2. Reintroduction of miR-194 might be a therapeutic approach to prevent and cure liver fibrosis.