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Mechanisms and consequences of oxidant-induced renal preconditioning: an Nrf2-dependent, P21-independent, anti-senescence pathway.
- Source :
-
Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association [Nephrol Dial Transplant] 2018 Nov 01; Vol. 33 (11), pp. 1927-1941. - Publication Year :
- 2018
-
Abstract
- Background: P21, a cyclin kinase inhibitor, is upregulated by renal 'ischemic preconditioning' (IPC), and induces a 'cytoresistant' state. However, P21-induced cell cycle inhibition can also contribute to cellular senescence, a potential adverse renal event. Hence, this study assessed whether: (i) IPC-induced P21 upregulation is associated with subsequent renal senescence; and (ii) preconditioning can be established 'independent' of P21 induction and avoid a post-ischemic senescent state?<br />Methods: CD-1 mice were subjected to either IPC (5-15 min) or to a recently proposed 'oxidant-induced preconditioning' (OIP) strategy (tin protoporphyrin-induced heme oxygenase inhibition +/- parental iron administration). P21 induction [messenger RNA (mRNA)/protein], cell proliferation (KI-67, phosphohistone H3 nuclear staining), kidney senescence (P16ink4a; P19Arf mRNAs; senescence-associated beta-galactosidase levels) and resistance to ischemic acute kidney injury were assessed.<br />Results: IPC induced dramatic (10-25×) and persistent P21 activation and 'downstream' tubular senescence. Conversely, OIP did not upregulate P21, it increased, rather than decreased, cell proliferation markers, and it avoided a senescence state. OIP markedly suppressed ischemia-induced P21 up-regulation, it inhibited the development of post-ischemic senescence and it conferred near-complete protection against ischemic acute renal failure (ARF). To assess OIP's impact on a non-P21-dependent cytoprotective pathway, its ability to activate Nrf2, the so-called 'master regulator' of endogenous cell defenses, was assessed. Within 4 h, OIP activated each of three canonical Nrf2-regulated genes (NQO1, SRXN1, GCLC; 3- to 5-fold mRNA increases). Conversely, this gene activation pathway was absent in Nrf2-/- mice, confirming Nrf2 specificity. Nrf2-/- mice also did not develop significant OIP-mediated protection against ischemic ARF.<br />Conclusions: OIP (i) activates the cytoprotective Nrf2, but not the P21, pathway; (ii) suppresses post-ischemic P21 induction and renal senescence; and (iii) confers marked protection against ischemic ARF. In sum, these findings suggest that OIP may be a clinically feasible approach for safely activating the Nrf2 pathway, and thereby confer protection against clinical renal injury.
- Subjects :
- Animals
Cell Cycle Checkpoints drug effects
Cyclin-Dependent Kinase Inhibitor p21 genetics
Heme Oxygenase (Decyclizing) antagonists & inhibitors
Male
Mice
Mice, Knockout
Protoporphyrins pharmacology
Acute Kidney Injury prevention & control
Cellular Senescence drug effects
Cyclin-Dependent Kinase Inhibitor p21 metabolism
Gene Expression Regulation drug effects
Ischemic Preconditioning methods
NF-E2-Related Factor 2 physiology
Oxidants pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 1460-2385
- Volume :
- 33
- Issue :
- 11
- Database :
- MEDLINE
- Journal :
- Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association
- Publication Type :
- Academic Journal
- Accession number :
- 29522116
- Full Text :
- https://doi.org/10.1093/ndt/gfy029