[en] Introduction: Whole-body irradiation has been associated with renal ischemic preconditioning in
mice. We investigate the fundamental impact of radiotherapy centered on the kidneys before renal
ischemia-reperfusion(IR). Methods: Experience1: Two beams of X-rays targeted mice kidneys to
deliver a 8,56Gy dose. One month later, a right nephrectomy was performed, and a left renal
ischemia was induced for 30min. After 48hours of reperfusion, the blood and left kidneys were
collected. Controls underwent a similar renal IR procedure, without irradiation. Experience2:
Unilateral irradiation of left kidneys(8.56 Gy) was performed on mice. One month later, the left
kidneys were collected. Additionally, kidneys were collected from non-irradiated mice. Irradiated
and control kidneys were used for comparative RNA-Seq. Illumina and DAVID program were used.
Results: Following renal IR, blood urea nitrogen levels were lower in irradiated mice(148.4±93.1)
compared to controls(495.7±33.3,p<0.01). The number of PCNA-positives cells was lower in
irradiated mice(130.8±52.7) compared to controls(545.4±257.3,p<0.001). The renal infiltration by
CD11b-positives cells(90.2±32.2)vs.(414.5±148.6) and F4-80
macrophages(80.6±22.9)vs.(178.5±68) was reduced in irradiated animals. Comparative
transcriptomics showed an upregulation of signaling pathways of angiogenesis(HMOX1) and
stress response(HSPA1A, HSPA1B) and a downregulation of oxidoreduction(NOX4). Conclusion
Kidney irradiation induces ischemic preconditioning in mice, with improved renal function and
decreased inflammation following renal IR. The aforementioned signaling pathways may play a
role in irradiation-associated kidney resistance to IR.
