Linked Life Data

16135540

Source:http://linkedlifedata.com/resource/pubmed/id/16135540

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-12-12
pubmed:abstractText
Calreticulin (CRT), a Ca2+-binding molecular chaperone in the endoplasmic reticulum, plays a vital role in cardiac physiology and pathology. Oxidative stress is a main cause of myocardiac apoptosis in the ischemic heart, but the function of CRT under oxidative stress is not fully understood. In the present study, the effect of overexpression of CRT on susceptibility to apoptosis under oxidative stress was examined using myocardiac H9c2 cells transfected with the CRT gene. Under oxidative stress due to H2O2, the CRT-overexpressing cells were highly susceptible to apoptosis compared with controls. In the overexpressing cells, the levels of cytoplasmic free Ca2+ ([Ca2+]i) were significantly increased by H2O2, whereas in controls, only a slight increase was observed. The H2O2-induced apoptosis was enhanced by the increase in [Ca2+]i caused by thapsigargin in control cells but was suppressed by BAPTA-AM, a cell-permeable Ca2+ chelator in the CRT-overexpressing cells, indicating the importance of the level of [Ca2+]i in the sensitivity to H2O2-induced apoptosis. Suppression of CRT by the introduction of the antisense cDNA of CRT enhanced cytoprotection against oxidative stress compared with controls. Furthermore, we found that the levels of activity of calpain and caspase-12 were elevated through the regulation of [Ca2+]i in the CRT-overexpressing cells treated with H2O2 compared with controls. Thus we conclude that the level of CRT regulates the sensitivity to apoptosis under oxidative stress due to H2O2 through a change in Ca2+ homeostasis and the regulation of the Ca2+-calpain-caspase-12 pathway in myocardiac cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0363-6143
pubmed:author
pubmed:issnType
Print
pubmed:volume
290
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C208-21
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Role of calreticulin in the sensitivity of myocardiac H9c2 cells to oxidative stress caused by hydrogen peroxide.
pubmed:affiliation
Dept. of Biochemistry and Molecular Biology in Disease, Atomic Bomb Disease Institute, Nagasaki Univ. Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan. y-ihara@net.nagasaki-u.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't