Published online Aug 14, 2018. doi: 10.3748/wjg.v24.i30.3414
Peer-review started: May 10, 2018
First decision: June 11, 2018
Revised: June 27, 2018
Accepted: June 28, 2018
Article in press: June 28, 2018
Published online: August 14, 2018
To explore the role and mechanism of total flavone of Abelmoschus manihot (TFA) on epithelial-mesenchymal transition (EMT) progress of Crohn’s disease (CD) intestinal fibrosis.
First, CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial (IEC-6) cells and select the optimal concentrations of TFA for our further studies. Then cell morphology, wound healing and transwell assays were performed to examine the effect of TFA on morphology, migration and invasion of IEC-6 cells treated with TGF-β1. In addition, immunofluorescence, real-time PCR analysis (qRT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress. Moreover, western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways. Further, the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by qRT-PCR, western blotting, morphology, wound healing and transwell assays.
In this study, TFA promoted transforming growth factor-β1 (TGF-β1)-induced (IEC-6) morphological change, migration and invasion, and increased the expression of epithelial markers and reduced the levels of mesenchymal markers, along with the inactivation of Smad and MAPK signaling pathways. Moreover, we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells. Importantly, co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.
These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.
Core tip: Regulating transforming growth factor-β (TGF-β) and its downstream signaling pathways, mediating the epithelial-mesenchymal transition (EMT) process and restoring the biological function of abnormally activated intestinal fibroblasts, may be an important way to seek drug therapy for Crohn’s disease (CD) intestinal fibrosis. Total flavone of Abelmoschus manihot (TFA) can inhibit TGF-β1-induced morphological change, migration, invasion of rat intestinal epithelial cells, and promote induction of EMT partially by inhibiting TGF-β1-activated Smad and non-Smad signaling pathways. Therefore, TFA is expected to advance as a new therapy to treat CD intestinal fibrosis, and its continued advancement may open the door to a new class of treatment for CD intestinal fibrosis.