Abstract: SA-PO715

Effect of TonEBP on TGF-β1-induced Phenotype Transition of Mesothelial Cells via Modulation of NLRP3 Inflammasome

Session Information

  • Peritoneal Dialysis - II
    November 04, 2017 | Location: Hall H, Morial Convention Center
    Abstract Time: 10:00 AM - 10:00 AM

Category: Dialysis

  • 608 Peritoneal Dialysis

Authors

  • Kang, Duk-Hee, Ewha University College of Medicine, Seoul, Korea (the Republic of)
  • Ryu, Eun sun, Ewha Womans University School of Medicine, Seoul, Korea (the Republic of)
  • Kim, Dal-ah, Ewha Womans University Medical Center, Seoul, seoul, Korea (the Republic of)
  • Kang, Hyun-Jung, Ewha Womans University , Seoul, Korea (the Republic of)
Background

Phenotype transition of mesothelial cells(MC) such as epithelial-to-mesenchymal transition(EMT) is known as an early mechanism of peritoneal fibrosis in peritoneal dialysis(PD). Nod-like receptor 3(NLRP3) inflammasome is comprised of the NLRP3, the adapter ASC and pro-caspase-1, which promotes the maturation of IL-1β and IL-18. Tonicity-responsive enhancer binding protein(TonEBP) is a transcriptional enhancer that enables cellular adaptation to hypertonic stress by promoting expression of specific genes. The aim of this study is to investigate whether TonEBP plays a role on phenotype transition via a modulation of NLRP3 inflammasome in peritoneal MCs isolated from omentum and dialysate effluents from patients on PD

Methods

The expressions of TonEBP and components of NLRP3 inflammasome, nuclear translocation of TonEBP and snail were evaluated by western blotting. E-cadherin promoter activity was confirmed by luciferase assay. Effect of either TonEBP or NLRP3 gene silencing on EMT was examined using siRNA technique. MCs were also isolated from overnight dwell dialysates from 9 clinically stable PD patients (MC-DE) to assess the expression of TonEBP and NLRP3 inflammasome, and to clarify the association with the markers of EMT

Results

TGFβ1 enhanced TonEBP expression with an increased nuclear translocation in MC, which was followed by an altered expression of epithelial and mesenshymal cell markers. TGFβ1 also activated the expression of NLRP3, ASC and procaspase-1 with an increased production of IL-1β and IL-18. TGFβ1-induced EMT was ameliorated by either siTonEBP or siNLRP3, which was associated with a decrease in snail expression and an increase in E-cadherin promotor activity. TonEBP gene silencing also alleviated TGFβ1-induced activation of NLRP3 inflammasome pathway. The expressions of TonEBP and NLRP3 were higher in MC-DE compared to MC never been exposed to dialysate, which were significantly correlated with the degree of EMT assessed by an altered expression of E-cadherin and α-SMA

Conclusion

This data suggest TonEBP plays a key role in peritoneal EMT via tonicity-independent mechanism by either an inhibition of E-cadherin transcription or an activation of the NLRP3 inflammasome. Modulation of TonEBP in MCs could be a novel approach to protect the peritoneum from the development of EMT and peritoneal fibrosis in PD patients