Abstract: TH-PO018
The Role of Cysteine Cathepsins in Lipopolysaccharide-Induced Preconditioning in the Mouse Kidney
Session Information
- AKI: Mechanisms - Primary Injury and Repair - I
November 07, 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
- Hamar, Peter, Semmelweis University, Budapest, Hungary
- Tod, Pál, Semmelweis University, Budapest, Hungary
- Vidmar, Robert, Jozef Stefan Institute, Ljubljana, Slovenia
- Vizovisek, Matej, Jozef Stefan Institute, Ljubljana, Slovenia
- Róka, Beáta, Semmelweis University, Budapest, Hungary
- Szénási, Gábor, Semmelweis University, Budapest, Hungary
- Fonovic, Marko, Jozef Stefan Institute, Ljubljana, Slovenia
- Turk, Boris, Jozef Stefan Institute, Ljubljana, Slovenia
Background
Cysteine cathepsins along with legumain are associated with diverse biological processes, e.g. antigen processing and presentation. Several studies investigated the potential role of cysteine cathepsins in preconditioning in the brain and heart. The aim of our study was to examine their probable involvement in LPS-induced preconditioning in the kidney.
Methods
Kidney samples were collected from male NMRI mice injected with LPS at 40 mg/kg i.p. and sacrificed at 1.5 and 6 hours (early preconditioning, EP) or at 10 mg/kg i.p. and sacrificed at 24 and 48 hours (late preconditioning, LP). Control animals received an equal volume of saline. Renal function was assessed by plasma urea levels and NGAL mRNA expression. The inflammatory response to LPS was evaluated by TNF-α and IL-6 mRNA expression levels. Cathepsin B, H, Z (Cat B, H, Z) and legumain protein levels were measured by HPLC-MS/MS and Western blot (WB), mRNA expression was quantified using real-time PCR and legumain activity was evaluated using an enzyme assay.
Results
LPS administration induced acute kidney injury and provoked a strong inflammatory response. Only the Cat B mRNA was elevated in EP but no alteration in any Cat protein or legumain expression was detected. Cat B and Z mRNA expression peaked at 24 hours and begun to decrease at 48 hours compared to the saline group. In align with these observations Cat B and Z protein levels were elevated at both time points. Legumain mRNA expression gradually increased after LPS administration and was markedly elevated at 6 hours in EP and 24 and 48 hours in LP. A significant increase in legumain protein levels was detected by MS at 48 hours and validated by WB. Legumain activity showed a marked increase at 48 h in comparison to the saline group.
Conclusion
The current results suggest that cysteine cathepsins and legumain may play a role only in the late phase of LPS-induced preconditioning.
Funding
- Government Support - Non-U.S.