| First Author | Chen L | Year | 2016 |
| Journal | Am J Pathol | Volume | 186 |
| Issue | 11 | Pages | 2921-2933 |
| PubMed ID | 27662798 | Mgi Jnum | J:237997 |
| Mgi Id | MGI:5817839 | Doi | 10.1016/j.ajpath.2016.07.011 |
| Citation | Chen L, et al. (2016) Fibrogenic Signaling Is Suppressed in Hepatic Stellate Cells through Targeting of Connective Tissue Growth Factor (CCN2) by Cellular or Exosomal MicroRNA-199a-5p. Am J Pathol 186(11):2921-2933 |
| abstractText | Pathways of liver fibrosis are controlled by connective tissue growth factor (CCN2). In this study, CCN2 was identified as a target of miR-199a-5p, which was principally expressed in quiescent mouse hepatic stellate cells (HSCs) and directly suppressed production of CCN2. Up-regulated CCN2 expression in fibrotic mouse livers or in activated primary mouse HSCs was associated with miR-199a-5p down-regulation. MiR-199a-5p in quiescent mouse HSCs inhibited the activity of a wild-type CCN2 3' untranslated region (3'-UTR) but not of a mutant CCN2 3'-UTR lacking the miR-199a-5p-binding site. In activated mouse HSCs, CCN2, alpha-smooth muscle actin, and collagen 1(alpha1) were suppressed by a miR-199a-5p mimic, whereas in quiescent mouse HSCs, the inhibited CCN2 3'-UTR activity was blocked by a miR-199a-5p antagomir. CCN2 3'-UTR activity in human HSCs was reduced by a miR-199a-5p mimic. MiR-199a-5p was present at higher levels in exosomes from quiescent versus activated HSCs. MiR-199a-5p-containing exosomes were shuttled from quiescent mouse HSCs to activated mouse HSCs in which CCN2 3'-UTR activity was then suppressed. Exosomes from quiescent HSCs caused miR-199a-5p-dependent inhibition of CCN2, alpha-smooth muscle actin, or collagen 1(alpha1) in activated HSCs in vitro and bound to activated HSCs in vivo. Thus, CCN2 suppression by miR-199a-5p accounts, in part, for low-level fibrogenic gene expression in quiescent HSCs and causes dampened gene expression in activated HSCs after horizontal transfer of miR-199a-5p in exosomes from quiescent HSCs. |
