Abstract

The epithelial-mesenchymal transition (EMT) of tubular epithelial cells (TECs) is crucial for the induction and progression of kidney fibrosis. However, the underlying molecular mechanisms that trigger the EMT programme have not been identified. In the present study, we demonstrate that transforming growth factor (TGF)-β1 and activated hedgehog signaling mediate the EMT programme following kidney injury. Tissue samples from fibrotic kidneys show enhanced TGF-β1 levels, as well as upregulated hedgehog signaling activity, during the EMT process; these levels decrease when fibrosis is reversed. Injury promotes TGF-β1 expression and activates hedgehog signaling, thus inducing tubular EMT of TECs and extracellular matrix (ECM) accumulation in vitro. The EMT response and fibrotic appearance are also induced by enhanced TGF-β1 levels or activated hedgehog signaling. Downregulation of TGF-β1 inhibits aristolochic acid (AA)- and TGF-β1-induced EMT and ECM synthesis and correlates with decreased hedgehog signaling. Similarly, inhibiting the hedgehog pathway abolishes AA- and hedgehog-mediated EMT, resulting in reduced TGF-β1 levels. These findings highlight a key role for cross-talk between TGF-β1 and hedgehog signaling in promoting injury-induced EMT and ECM deposition in TECs.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.