Targeting activated kidney fibroblasts via ferroptosis: a potential antifibrotic strategy

Kidney fibrosis is characterized by excessive deposition of extracellular matrix, which is ultimately disrupting normal renal architecture. Despite its clinical relevance, no targeted antifibrotic therapies are currently available. Myofibroblasts, primarily derived from pericytes and resident fibroblasts, are key effectors of fibrosis due to their high extracellular matrix production. Here, we tested the hypothesis that ferroptosis induction would enable the targeted elimination of activated kidney fibroblasts. We found that kidney fibroblasts exhibit marked sensitivity to ferroptotic cell death upon exposure to the ferroptosis inducer RAS-selective lethal 3 (RSL3), an effect further amplified by transforming growth factor-β stimulation. In tissue slice cultures of murine fibrotic kidneys, RSL3 eliminated myofibroblasts without causing overt damage to other cell types. Extending these findings in vivo, we applied a postischemia/reperfusion model of kidney fibrosis and demonstrated that repeated low-dose systemic administration of RSL3 significantly reduced the activated fibroblast population without inducing appreciable injury to parenchymal cells. These results provide proof-of-principle that the ferroptosis susceptibility of activated fibroblasts may offer a potential strategy for the selective depletion of profibrotic effector cells in kidney fibrosis.<b>NEW & NOTEWORTHY</b> This study reveals ferroptosis, a pharmacologically inducible form of cell death, as a novel mechanism to eliminate activated fibroblasts, the main drivers of kidney fibrosis. Due to their high ferroptosis sensitivity, these cells are selectively depleted by RSL3 in vitro, in kidney tissue slice cultures, and in fibrotic kidneys in vivo. These findings highlight ferroptosis induction as a promising antifibrotic strategy in kidney disease.