Heme oxygenase-1 inhibits renal tubular macroautophagy in acute kidney injury.

Academic Article

Abstract

  • Autophagy is a tightly regulated, programmed mechanism to eliminate damaged organelles and proteins from a cell to maintain homeostasis. Cisplatin, a chemotherapeutic agent, accumulates in the proximal tubules of the kidney and causes dose-dependent nephrotoxicity, which may involve autophagy. In the kidney, cisplatin induces the protective antioxidant heme oxygenase-1 (HO-1). In this study, we examined the relationship between autophagy and HO-1 during cisplatin-mediated acute kidney injury (AKI). In wild-type primary proximal tubule cells (PTC), we observed a time-dependent increase in autophagy after cisplatin. In HO-1(-/-) PTC, however, we observed significantly higher levels of basal autophagy, impaired progression of autophagy, and increased apoptosis after cisplatin. Restoring HO-1 expression in these cells reversed the autophagic response and inhibited apoptosis after treatment with cisplatin. In vivo, although both wild-type and HO-1-deficient mice exhibited autophagosomes in the proximal tubules of the kidney in response to cisplatin, HO-1-deficient mice had significantly more autophagosomes, even in saline-treated animals. In addition, ecdysone-induced overexpression of HO-1 in cells led to a delay in autophagy progression, generated significantly lower levels of reactive oxygen species, and protected against cisplatin cytotoxicity. These findings demonstrate that HO-1 inhibits autophagy, suggesting that the heme oxygenase system may contain therapeutic targets for AKI.
  • Keywords

  • Acute Kidney Injury, Animals, Antineoplastic Agents, Autophagy, Cisplatin, Heme Oxygenase-1, Humans, Kidney Tubules, Proximal, Mice, Mice, Inbred C57BL, Mice, Knockout, Reactive Oxygen Species
  • Digital Object Identifier (doi)

    Author List

  • Bolisetty S; Traylor AM; Kim J; Joseph R; Ricart K; Landar A; Agarwal A
  • Start Page

  • 1702
  • End Page

  • 1712
  • Volume

  • 21
  • Issue

  • 10