Abstract: SA-PO121
Pyruvate Kinase M2 Mediates Fibroblasts Activation Alleviates AKI
Session Information
- AKI: Mechanisms - AKI-CKD Transition
November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
Authors
- Ye, Yinyin, Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, China
- Jiang, Lei, Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, China
- Yang, Junwei, Center for Kidney Disease, Second Affiliated Hospital, Nanjing Medical University, Nanjing, China
Background
Acute kidney injury (AKI) is a devastating condition with high morbidity and mortality. The pathologic features of AKI are characterized by tubular injury, infiltration of inflammation cells and vascular integrity impairment. Pyruvate kinase is the last rate-limiting enzyme in the glycolysis pathway, We have previously shown that Pyruvate kinase M2 (PKM2) plays an important role in regulating the glycolytic recombination of fibroblasts in chronic kidney disease. But the role of PKM2 in fibroblasts in the pathogenesis of AKI is unknown.
Methods
Lentivirus was used to down-regulate PKM2 expression in NRK-49F cells, and then analyzed the expression of the key enzymes of glycolysis and the ability of cell proliferation .In vivo, we generated fibroblast specific PKM2 knockout mice (Fibroblast-PKM2-/- mice) by crossbreeding PKM2-flox mice with S00A4-Cre mice. Then we compared renal function, expression of urinary KIM-1 and NGAL, pathological damage and renal tubular cell apoptosis between Fibroblast-PKM2-/- mice and control mice after ischemia-reperfusion injury(I/R) or folic acid (FA) injection. Reno-protective factors secreted by fibroblasts such as HGF and EPO were determined by RT-PCR and Elisa. Co-culture of NRK-52E cells and NRK-49F cells under oxygen deprivation condition was used to investigate the interaction between fibroblasts and renal tubular cells.
Results
Down-regulation of PKM2 can reduce glycolysis level and decrease the ability of proliferation of NRK-49F cells. Compared with control mice, Fibroblast-PKM2-/- mice had less fibroblast activation, more kidney injury indicated by increased BUN , KIM-1 and NGAL levels and more apoptosis of tubular epithelial cells after AKI induced by I/R or FA injury . Furthermore, Fibroblast-PKM2-/- mice secreted lower renal protective factors such as HGF and EPO. Additionally, Fibroblast-PKM2-/- mice showed suppressed of HGF-cmet signaling and decreased expression of p-ERK and p-bad. Co-culture experiment in oxygen deprivation condition revealed that down-regulation of PKM2 in NRK-49Fcells could decrease the expression of HGF and EPO in NRK-49F cells and inhibit fibroblast activation, and increase apoptosis in NRK-52E cells.
Conclusion
Collectively, these results suggest that PKM2 mediated fibroblasts activation plays a critical role in the pathogenesis of AKI.
Funding
- Government Support - Non-U.S.