Cell-Specific Image-guided Transcriptomics of Ischemic Acute Kidney Injury

The highly heterogeneous nature of the kidney's tubular epithelium has made it challenging to identify unique, cell-specific pathways particularly when renal injury causes the loss of fiduciary landmarks. Here, we combine a cell-specific luciferase reporter system with a chemo-selective substrate to identify specific Òat riskÓ tissues. We demonstrate that this platform system has the power to identify both cell-specific pathophysiological events and cell-specific transcriptional changes and consequently can identify novel therapeutic targets. Using the kidney ischemia-reperfusion model (iAKI), we found that lipid peroxidation mirrored H2O2 generation but with entirely different timing and sensitivity to ischemia depending on the nephron segment. We found the collecting duct demonstrated intensive ROS generation and transcriptional analysis demonstrated mitochondrial distress. In fact, pretreatment with a single bolus of a mitochondrial antioxidant, MitoTEMPO delayed ROS generation and significantly reduced acute oxidative stress associated injury. These data demonstrate that iAKI differentially targets different nephron segments, demonstrating the complexity of kidney injury includes multiple segments. Our in vivo ROS detection system can explore complex injuries in heterogeneous organs by leveraging image guidance for tissue interrogation. Kidney collecting duct cell mRNA profiles of mice after ischemia/reperfusion injury or control (sham), n=4 per condition, were generated by deep sequencing,using Illumina HiSeq.