Single-cell analysis highlights differences in druggable pathways underlying adaptive or fibrotic kidney regeneration

The kidney tubules have tremendous capacity to repair after acute injury, however, pathways guiding adaptive and maladaptive (fibrotic) repair are poorly understood. We developed a model of adaptive and maladaptive kidney regeneration by titrating ischemic injury dose. We performed detailed biochemical and histological analysis and profiled transcriptomic changes at bulk and single-cell level in >110,000 cells over time. Our analysis highlighted kidney proximal tubule (PT) cells as key susceptible cells to injury. Adaptive PT repair correlated with fatty acid oxidation and oxidative phosphorylation. We identified a specific maladaptive/profibrotic PT cluster after long ischemia. These cells expressed proinflammatory and profibrotic cytokines and myeloid cell chemotactic factor. Druggability analysis highlighted pyroptosis and ferroptosis as vulnerable pathways in these profibrotic cells. Pharmacological targeting of pyroptosis/ferroptosis in animal model, pushed cells towards adaptive repair and successfully reduced fibrosis. In summary, our single-cell analysis defined key differences in adaptive and maladaptive repair and identified druggable pathways for pharmacological intervention to prevent kidney fibrosis. Overall design: n=20 mouse kidney scRNA-seq samples; n=6 control, n=2 IRI short 1d, n=2 IRI short 3d, n=2 IRI short 14d, n=2 IRI long 1d, n=2 IRI long 3d, n=2 IRI long 14d, n=1 IRI long 14d+VX765, n=1 IRI long 14d+Liproxstatin