The role of hypoxia-inducible factor-1α in acetaminophen hepatotoxicity

J Pharmacol Exp Ther. 2011 Aug;338(2):492-502. doi: 10.1124/jpet.111.180521. Epub 2011 May 16.

Abstract

Hypoxia-inducible factor-1α (HIF-1α) is a critical transcription factor that controls oxygen homeostasis in response to hypoxia, inflammation, and oxidative stress. HIF has been implicated in the pathogenesis of liver injury in which these events play a role, including acetaminophen (APAP) overdose, which is the leading cause of acute liver failure in the United States. APAP overdose has been reported to activate HIF-1α in mouse livers and isolated hepatocytes downstream of oxidative stress. HIF-1α signaling controls many factors that contribute to APAP hepatotoxicity, including mitochondrial cell death, inflammation, and hemostasis. Therefore, we tested the hypothesis that HIF-1α contributes to APAP hepatotoxicity. Conditional HIF-1α deletion was generated in mice using an inducible Cre-lox system. Control (HIF-1α-sufficient) mice developed severe liver injury 6 and 24 h after APAP overdose (400 mg/kg). HIF-1α-deficient mice were protected from APAP hepatotoxicity at 6 h, but developed severe liver injury by 24 h, suggesting that HIF-1α is involved in the early stage of APAP toxicity. In further studies, HIF-1α-deficient mice had attenuated thrombin generation and reduced plasminogen activator inhibitor-1 production compared with control mice, indicating that HIF-1α signaling contributes to hemostasis in APAP hepatotoxicity. Finally, HIF-1α-deficient animals had decreased hepatic neutrophil accumulation and plasma concentrations of interleukin-6, keratinocyte chemoattractant, and regulated upon activation normal T cell expressed and secreted compared with control mice, suggesting an altered inflammatory response. HIF-1α contributes to hemostasis, sterile inflammation, and early hepatocellular necrosis during the pathogenesis of APAP toxicity.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Acetaminophen / toxicity*
  • Animals
  • Chemical and Drug Induced Liver Injury / metabolism*
  • Chemical and Drug Induced Liver Injury / pathology
  • Chemical and Drug Induced Liver Injury / prevention & control
  • Hepatocytes / drug effects*
  • Hepatocytes / metabolism*
  • Hepatocytes / pathology
  • Hypoxia-Inducible Factor 1, alpha Subunit / physiology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Oxidative Stress / drug effects
  • Oxidative Stress / physiology

Substances

  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Acetaminophen