Document Detail

Effects of thymoquinone on isolated and cellular proteasomes.
MedLine Citation:
PMID:  20412058     Owner:  NLM     Status:  MEDLINE    
Thymoquinone, a naturally derived agent, has been shown to possess antioxidant, antiproliferative and proapoptotic activities. In the present study, we explored thymoquinone effects on the proteasomal complex, the major system involved in the removal of damaged, oxidized and misfolded proteins. In purified 20S complexes, subunit-dependent and composition-dependent inhibition was observed, and the chymotrypsin-like and trypsin-like activities were the most susceptible to thymoquinone treatment. U87 MG and T98G malignant glioma cells were treated with thymoquinone, and 20S and 26S proteasome activity was measured. Inhibition of the complex was evident in both cell lines, but predominantly in U87 MG cells, and was accompanied by accumulation of ubiquitin conjugates. Accumulation of p53 and Bax, two proteasome substrates with proapoptotic activity, was observed in both cell lines. Our results demonstrate that thymoquinone induces selective and time-dependent proteasome inhibition, both in isolated enzymes and in glioblastoma cells, and suggest that this mechanism could be implicated in the induction of apoptosis in cancer cells.
Valentina Cecarini; Luana Quassinti; Alessia Di Blasio; Laura Bonfili; Massimo Bramucci; Giulio Lupidi; Massimiliano Cuccioloni; Matteo Mozzicafreddo; Mauro Angeletti; Anna Maria Eleuteri
Related Documents :
7586148 - P53 expression in normal versus transformed mammalian cells.
10785598 - Molecular downstream events and induction of thymidylate synthase in mutant and wild-ty...
20819578 - Ursolic acid induces human hepatoma cell line smmc-7721 apoptosis via p53-dependent pat...
12750388 - Tumor suppressor p53 and its homologue p73alpha affect cell migration.
12048028 - Mouse resident peritoneal macrophages partially control in vitro infection with coxiell...
262558 - Involvement of mitochondria in changes in fluorescein excitation and emission polarizat...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The FEBS journal     Volume:  277     ISSN:  1742-4658     ISO Abbreviation:  FEBS J.     Publication Date:  2010 May 
Date Detail:
Created Date:  2010-04-23     Completed Date:  2010-05-05     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101229646     Medline TA:  FEBS J     Country:  England    
Other Details:
Languages:  eng     Pagination:  2128-41     Citation Subset:  IM    
University of Camerino, Italy. <>
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Benzoquinones / pharmacology*
Cell Line, Tumor
Cell Proliferation / drug effects
Glioblastoma / metabolism,  pathology
Molecular Structure
Protease Inhibitors / pharmacology*
Proteasome Endopeptidase Complex / antagonists & inhibitors*,  isolation & purification,  metabolism
Tumor Suppressor Protein p53 / metabolism
bcl-2-Associated X Protein / metabolism
Reg. No./Substance:
0/BAX protein, human; 0/Benzoquinones; 0/Protease Inhibitors; 0/TP53 protein, human; 0/Tumor Suppressor Protein p53; 0/bcl-2-Associated X Protein; 490-91-5/thymoquinone; EC Endopeptidase Complex

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  The ROQUIN family of proteins localizes to stress granules via the ROQ domain and binds target mRNAs...
Next Document:  Drosophila proteins involved in metabolism of uracil-DNA possess different types of nuclear localiza...