First Author | Zahedi K | Year | 2014 |
Journal | PLoS One | Volume | 9 |
Issue | 11 | Pages | e110161 |
PubMed ID | 25390069 | Mgi Jnum | J:225155 |
Mgi Id | MGI:5691638 | Doi | 10.1371/journal.pone.0110161 |
Citation | Zahedi K, et al. (2014) Proximal tubule epithelial cell specific ablation of the spermidine/spermine N1-acetyltransferase gene reduces the severity of renal ischemia/reperfusion injury. PLoS One 9(11):e110161 |
abstractText | BACKGROUND: Expression and activity of spermidine/spermine N1-acetyltransferase (SSAT) increases in kidneys subjected to ischemia/reperfusion (I/R) injury, while its ablation reduces the severity of such injuries. These results suggest that increased SSAT levels contribute to organ injury; however, the role of SSAT specifically expressed in proximal tubule epithelial cells, which are the primary targets of I/R injury, in the mediation of renal damage remains unresolved. METHODS: Severity of I/R injury in wt and renal proximal tubule specific SSAT-ko mice (PT-SSAT-Cko) subjected to bilateral renal I/R injury was assessed using cellular and molecular biological approaches. RESULTS: Severity of the loss of kidney function and tubular damage are reduced in PT-SSAT-Cko- compared to wt-mice after I/R injury. In addition, animals treated with MDL72527, an inhibitor of polyamine oxidases, had less severe renal damage than their vehicle treated counter-parts. The renal expression of HMGB 1 and Toll like receptors (TLR) 2 and 4 were also reduced in PT-SSAT-Cko- compared to wt mice after I/R injury. Furthermore, infiltration of neutrophils, as well as expression of tumor necrosis factor-alpha (TNF-alpha), monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6) transcripts were lower in the kidneys of PT-SSAT-Cko compared to wt mice after I/R injury. Finally, the activation of caspase3 was more pronounced in the wt compared to PT-SSAT-Cko animals. CONCLUSIONS: Enhanced SSAT expression by proximal tubule epithelial cells leads to tubular damage, and its deficiency reduces the severity of renal I/R injury through reduction of cellular damage and modulation of the innate immune response. |