Glucocorticoids induce a maladaptive epithelial stress response to aggravate acute kidney injury [ATAC]

Acute kidney injury (AKI) is a frequent and challenging clinical condition associated with high morbidity and mortality. In AKI, renal tubular epithelial cells (TECs) are a primary site of damage, and recovery from AKI depends on TEC plasticity. However, the molecular mechanisms underlying adaptation and maladaptation of TECs in AKI remain largely unclear. Here, our analyses of mouse kidney tubuloids showed that TEC injury resulted in activation of the glucocortiocoid receptor by endogenous glucocorticoids, which aggravated tubular damage. The detrimental effect of endogenous glucocorticoids on injured TECs was exacerbated by the administration of the widely clinically used synthetic glucocorticoid, dexamethasone, as indicated by experiments in mouse kidney tubuloids. Mechanistically, studies in mouse tubuloids demonstrated that glucocorticoid receptor signaling in injured TECs orchestrated a maladaptive transcriptional program to hinder DNA repair and to amplify injury-induced DNA double-strand break formation, as well as to dampen mTOR activity and mitochondrial bioenergetics. This study identifies glucocortiocoid receptor activation as a mechanism of epithelial maladaptation, which is functionally important for acute kidney injury. Overall design: The renal cortices of 4 wildtype mice were dissected, and tubuloids were grown in matrigel. Tubuloids were treated without or with myoglobin (to induce tubular injury). After 12 hours of treatment, tubuloids were subjected to ATAC-seq.