title: Sonic hedgehog-mediated epithelial-mesenchymal transition in renal tubulointerstitial fibrosis.
abstract: The sonic hedgehog (SHH) signaling pathway plays a critical role in embryonic development, tissue regeneration and organogenesis. The activation of SHH signaling produces profibrogenic effects in various tissues, such as the liver and the biliary ducts. However, the role of SHH signaling in renal fibrogenesis remains to be elucidated. For this purpose, in the present study, we evaluated the hypothesis that activated SHH signaling promotes the acquisition of a myofibroblastic phenotype through the epithelial-mesenchymal transition (EMT), resulting in renal interstitial fibrosis (RIF). Kidney samples from rats subjected to unilateral or bilateral ureteral obstruction exhibited the enhanced expression of SHH-pathway proteins, mesenchymal markers and the decreased expression of epithelial markers. Overactive SHH signaling as well as tubular EMT and RIF in the obstructed kidneys were inhibited by recanalization of the ureter. In vitro, SHH signaling was activated during EMT induction and extracellular matrix (ECM) deposition was observed in transforming growth factor-β1 (TGF-β1)-treated renal tubular epithelial cells [RTECs; NRK-52E cell line]. Exogenous SHH activated SHH signaling and resulted in the upregulated expression of mesenchymal genes, the profibrogenic cytokine TGF-β1, and the downregulated expression of epithelial markers. The blockade of SHH signaling with cyclopamine abolished SHH-mediated EMT as well as the acquisition of a myofibroblastic phenotype, and decreased TGF-β1 expression and ECM production. Thus, taken together, these findings demonstrate that the activation of the SHH signaling pathway promotes the induction of EMT and renal tubulointerstitial fibrosis. The pharmacological inhibition of SHH signaling may potentially be of therapeutic value in the management of fibrotic kidney diseases.
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Yongheng
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lu
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Chengcheng
authors.initials: C
authors.lastname: Lin
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Yaya
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Dannü
authors.initials: D
authors.lastname: Hu
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Weilong
authors.initials: W
authors.lastname: Hong
authors.affiliation: Wenzhou Key Laboratory of Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.
authors.forename: Bicheng
authors.initials: B
authors.lastname: Chen
mesh_terms: D000818:Animals; D015415:Biomarkers; D004195:Disease Models, Animal; D058750:Epithelial-Mesenchymal Transition; D005109:Extracellular Matrix / Q000378:metabolism; D005355:Fibrosis; D053823:Hedgehog Proteins / Q000378:metabolism*; D007674:Kidney Diseases / Q000209:etiology / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D051381:Rats; D015398:Signal Transduction; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D014517:Ureteral Obstruction / Q000150:complications
chemical_list: D015415:Biomarkers; D053823:Hedgehog Proteins; D053773:Transforming Growth Factor beta1