Abstract: FR-PO372

RIPK3 Inhibition Alleviates Folic Acid-Induced Kidney Fibrosis of C57BL/6 Mouse

Session Information

Category: Chronic Kidney Disease (Non-Dialysis)

  • 308 CKD: Mechanisms of Tubulointerstitial Fibrosis

Authors

  • Shi, Ying, kolling institute, the University of Sydney, Sydney, New South Wales, Australia
  • Zhao, Yongli, The Second Hospital of Dalian Medical University, Dalian, China
  • Huang, Chunling, kolling institute, the University of Sydney, Sydney, New South Wales, Australia
  • Chen, Xinming, kolling institute, the University of Sydney, Sydney, New South Wales, Australia
  • Pollock, Carol A., kolling institute, the University of Sydney, Sydney, New South Wales, Australia
Background

Current therapies for renal fibrosis are largely ineffective. Therefore, identification of novel therapeutic targets is essential. RIPK3 is identified as a crucial regulator of necrosis, apoptosis and inflammation, which have been well recognised to be involved in renal fibrogenesis. To date, the role of RIPK3 in renal fibrosis has not been reported.

Methods

C57BL/6 wild-type and RIPK3 gene knock out (RIPK3-/-) mice and two interventional strategies were used in the study. 1. Folic acid was administrated i.p. to induce kidney injury in both WT and RIPK3-/- mice for 28 days; 2. C57BL/6 WT mice injected with folic acid were treated with Dabrafenib (RIPK3 inhibitor) or vehicle respectively for 28 days. Kidneys were harvested from above experiments and kidney function was assessed by measuring 24 hour of urinary albumin excretion and urinary albumin creatinine ratio (UACR) by ELISAs. Kidney histological change and ECM deposition was assessed by PAS, Masson's trichrome, picrosirius red staining and immunohistochemistry. MCP-1, TGF-β and a-SMA RNA expression level were detected by quantitative RT-PCR analysis.

Results

RIPK3 blockade reversed folic acid increased 24 hour urinary albumin excretion and decreased UACR compared to WT or vehicle control groups treated with folic acid. Histological analysis has shown that folic acid resulted in increased collagen accumulation and ECM deposition, whereas, RIPK3 inhibition attenuated ECM deposition and renal fibrosis. Similar results were also elucidated by immunohistochemistry on ECM components type I, III, IV Collagens and Fibronectin expression in renal interstitium. In addition, quantitative RT-PCR demonstrated Dabrafenib treated mice and RIPK3-/- mice inhibited RNA expression of MCP-1, TGF-β and a-SMA.

Conclusion

These results suggest that RIPK3 blockade may be a potential novel target in renal fibrosis.

Funding

  • Government Support - Non-U.S.