Linked Life Data

14722250

Source:http://linkedlifedata.com/resource/pubmed/id/14722250

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-1-14
pubmed:abstractText
Anthracyclines are potent anticancer agents, but their use is limited by cardiotoxicity at high cumulative doses. The mechanisms involved in anthracycline-mediated cardiotoxicity are still poorly understood, but numerous investigations have indicated a role for iron in this process. Our previous studies using neoplastic and myocardial cells showed that anthracyclines inhibit iron mobilization from the iron storage protein, ferritin, resulting in marked accumulation of ferritin-iron. Although the process of ferritin-iron mobilization is little understood, catabolism of ferritin by lysosomes may be a likely mechanism. Because anthracyclines have been shown to accumulate in lysosomes, this latter organelle may be a potential target for these drugs. The present study demonstrated, using native polyacrylamide gel electrophoresis-59Fe autoradiography, that ferritin-59Fe mobilization is an energy-dependent process that also requires protein synthesis. Depression of lysosomal activity via the enzyme inhibitors E64d [(2S,3S)-trans-epoxysuccinyl-l-leucylamido-2-methylbutane ethyl ester] and leupeptin or the lysosomotropic agents ammonium chloride, chloroquine, and methylamine resulted in a 3- to 5-fold increase in 59Feferritin accumulation compared with control cells. In addition, the proteasome inhibitors N-benzoyloxycarbonyl (Z)-Leu-Leuleucinal (MG132) and lactacystin also significantly increased 59Fe-ferritin levels compared with control cells. These effects of lysosomotropic agents or inhibitors of lysosomal activity were comparable with that observed with the anthracycline doxorubicin. Collectively, our study indicates a role for lysosomes and proteasomes in ferritin-iron mobilization, and this pathway is dependent on metabolic energy and protein synthesis. Furthermore, the lysosome/proteasome pathway may be a novel anthracycline target, inhibiting iron mobilization from ferritin that is essential for vital iron-requiring processes such as DNA synthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
181-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Examination of the mechanism(s) involved in doxorubicin-mediated iron accumulation in ferritin: studies using metabolic inhibitors, protein synthesis inhibitors, and lysosomotropic agents.
pubmed:affiliation
Children's Cancer Institute Australia for Medical Research, Iron Metabolism and Chelation Program, Randwick, Sydney, NSW, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't