Necrosis-like death can engage multiple pro-apoptotic Bcl-2 protein family members

Apoptosis. 2012 Nov;17(11):1197-1209. doi: 10.1007/s10495-012-0756-8.

Abstract

Necroptosis is a physiologically relevant mode of cell death with some well-described initiating events, but largely unknown executioners. Here we investigated necrostatin-1 (Nec-1) sensitive death elicited by different necroptosis stimuli in L929 mouse fibrosarcoma cells, mouse embryonic fibroblasts (MEF) and bone marrow-derived macrophages. We found that TNFα- or zVAD-induced necroptosis occurs independently of the recently implicated executioners Bmf or PARP-2, but can involve the Bcl-2 family proteins Bid and Bak. Furthermore, this type of necroptosis is associated with mitochondrial cytochrome c release and partly sensitive to cyclosporine A inhibition, suggesting a cross talk with the mitochondrial permeability transition pore. Necroptosis triggered by cadmium (Cd) exposure caused fully Nec-1-sensitive and caspase-independent death in L929 cells that was associated with autocrine TNFα-mediated feed-forward signalling. In MEF Cd-exposure elicited a mixed mode of cell death that was to some extent Nec-1-sensitive but also displayed features of apoptosis. It was partly dependent on Bmf and Bax/Bak, proteins typically considered to act pro-apoptotic, but ultimately insensitive to caspase inhibition. Overall, our study indicates that inducers of "extrinsic" and "intrinsic" necroptosis can both trigger TNF-receptor signalling. Further, necroptosis may depend on mitochondrial changes engaging proteins considered critical for MOMP during apoptosis that ultimately contribute to caspase-independent necrotic cell death.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Amino Acid Chloromethyl Ketones / pharmacology
  • Animals
  • Apoptosis / drug effects
  • Autocrine Communication / drug effects
  • Autophagy / drug effects
  • BH3 Interacting Domain Death Agonist Protein / metabolism
  • Cadmium / toxicity
  • Cell Line
  • Fibroblasts / drug effects
  • Fibroblasts / metabolism
  • Fibroblasts / pathology
  • Imidazoles / pharmacology
  • Indoles / pharmacology
  • Intracellular Membranes / drug effects
  • Intracellular Membranes / metabolism
  • Lysosomes / drug effects
  • Lysosomes / metabolism
  • Mice
  • Necrosis / metabolism*
  • Necrosis / pathology*
  • Poly(ADP-ribose) Polymerases / metabolism
  • Proto-Oncogene Proteins c-bcl-2 / metabolism*
  • Receptor-Interacting Protein Serine-Threonine Kinases / metabolism
  • Receptors, Tumor Necrosis Factor / metabolism
  • Tumor Necrosis Factor-alpha / pharmacology
  • bcl-2 Homologous Antagonist-Killer Protein / metabolism

Substances

  • Adaptor Proteins, Signal Transducing
  • Amino Acid Chloromethyl Ketones
  • BH3 Interacting Domain Death Agonist Protein
  • Bmf protein, mouse
  • Imidazoles
  • Indoles
  • Proto-Oncogene Proteins c-bcl-2
  • Receptors, Tumor Necrosis Factor
  • Tumor Necrosis Factor-alpha
  • bcl-2 Homologous Antagonist-Killer Protein
  • benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
  • necrostatin-1
  • Cadmium
  • Poly(ADP-ribose) Polymerases
  • Receptor-Interacting Protein Serine-Threonine Kinases
  • Ripk1 protein, mouse
  • Ripk3 protein, mouse