Efavirenz and 8-hydroxyefavirenz induce cell death via a JNK- and BimEL-dependent mechanism in primary human hepatocytes

Toxicol Appl Pharmacol. 2011 Dec 1;257(2):227-34. doi: 10.1016/j.taap.2011.09.008. Epub 2011 Sep 19.


Chronic use of efavirenz (EFV) has been linked to incidences of hepatotoxicity in patients receiving EFV to treat HIV-1. While recent studies have demonstrated that EFV stimulates hepatic cell death a role for the metabolites of efavirenz in this process has yet to be examined. In the present study, incubation of primary human hepatocytes with synthetic 8-hydroxyEFV (8-OHEFV), which is the primary metabolite of EFV, resulted in cell death, caspase-3 activation and reactive oxygen species formation. The metabolite exerted these effects at earlier time points and using lower concentrations than were required for the parent compound. In addition, pharmacological inhibition of cytochrome P450-dependent metabolism of EFV using 1-aminobenzotriazole markedly decreased reactive oxygen species formation and cell death. Treatment of primary human hepatocytes with EFV and 8-OHEFV also stimulated phosphorylation of c-Jun N-terminal kinase (JNK) as well as phosphorylation of the JNK substrate c-Jun. Further, the mRNA and protein expression of an isoform of Bim (Bcl-2 interacting mediator of cell death) denoted as BimEL, which is proapoptotic and has been shown to be modulated by JNK, was increased. Inhibition of JNK using SP600125 prevented the EFV- and 8-OHEFV-mediated cell death. Silencing of Bim using siRNA transfected into hepatocytes also prevented cell death resulting from 8-OHEFV-treatment. These data suggest that the oxidative metabolite 8-OHEFV is a more potent inducer of hepatic cell death than the parent compound EFV. Further, activation of the JNK signaling pathway and BimEL mRNA expression appear to be required for EFV- and 8-OHEFV-mediated hepatocyte death.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkynes
  • Apoptosis Regulatory Proteins / physiology*
  • Bcl-2-Like Protein 11
  • Benzoxazines / metabolism*
  • Benzoxazines / toxicity*
  • Cell Death / drug effects
  • Cell Death / physiology
  • Cyclopropanes
  • Enzyme Activation / drug effects
  • Enzyme Activation / physiology
  • Female
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism*
  • Humans
  • JNK Mitogen-Activated Protein Kinases / physiology*
  • Male
  • Membrane Proteins / physiology*
  • Middle Aged
  • Proto-Oncogene Proteins / physiology*
  • Reactive Oxygen Species / metabolism
  • Young Adult


  • Alkynes
  • Apoptosis Regulatory Proteins
  • BCL2L11 protein, human
  • Bcl-2-Like Protein 11
  • Benzoxazines
  • Cyclopropanes
  • Membrane Proteins
  • Proto-Oncogene Proteins
  • Reactive Oxygen Species
  • JNK Mitogen-Activated Protein Kinases
  • efavirenz