PUBLICATION

Nuclear factor {kappa}B inhibitors alleviate and the proteasome inhibitor PS-341 exacerbates radiation toxicity in zebrafish embryos

Authors
Daroczi, B., Kari, G., Ren, Q., Dicker, A.P., and Rodeck, U.
ID
ZDB-PUB-090914-20
Date
2009
Source
Molecular cancer therapeutics   8(9): 2625-2634 (Journal)
Registered Authors
Dicker, Adam P.
Keywords
enotoxic stress, zebrafish, NF-kappaB, radiation protective agents, proteasome inhibitor
MeSH Terms
  • Animals
  • Boronic Acids/pharmacology*
  • Bortezomib
  • Embryo, Nonmammalian/drug effects
  • Embryo, Nonmammalian/radiation effects*
  • NF-kappa B/antagonists & inhibitors*
  • Protease Inhibitors/pharmacology*
  • Proteasome Inhibitors*
  • Pyrazines/pharmacology*
  • Pyruvates/pharmacology
  • Reverse Transcriptase Polymerase Chain Reaction
  • Zebrafish/embryology*
PubMed
19723885 Full text @ Mol. Cancer Ther.
Abstract
Inflammatory changes are a major component of the normal tissue response to ionizing radiation, and increased nuclear factor kappaB (NF-kappaB) activity is an important mediator of inflammatory responses. Here, we used zebrafish embryos to assess the capacity of two different classes of pharmacologic agents known to target NF-kappaB to modify radiation toxicity in the vertebrate organism. These were proteasome inhibitors, including lactacystin, MG132, and PS-341 (Bortezomib/VELCADE), and direct inhibitors of NF-kappaB activity, including ethyl pyruvate (EP) and the synthetic triterpenoid CDDO-TFEA (RTA401), among others. The proteasome inhibitors either did not significantly affect radiation sensitivity of zebrafish embryos (MG132, lactacystin) or rendered zebrafish embryos more sensitive to the lethal effects of ionizing radiation (PS-341). Radiosensitization by PS-341 was reduced in fish with impaired p53 expression or function but not associated with enhanced expression of select p53 target genes. In contrast, the direct NF-kappaB inhibitors EP and CDDO-TFEA significantly improved overall survival of lethally irradiated zebrafish embryos. In addition, direct NF-kappaB inhibition reduced radiation-induced apoptosis in the central nervous system, abrogated aberrations in body axis development, restored metabolization and secretion of a reporter lipid through the gastrointestinal system, and improved renal clearance compromised by radiation. In contrast to amifostine, EP and CDDO-TFEA not only protected against but also mitigated radiation toxicity when given 1 to 2 hours postexposure. Finally, four additional IkappaB kinase inhibitors with distinct mechanisms of action similarly improved overall survival of lethally irradiated zebrafish embryos. In conclusion, inhibitors of canonical pathways to NF-kappaB activation may be useful in alleviating radiation toxicity in patients.
Genes / Markers
Figures
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Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping