Effects of polyamines on apoptosis induced by simulated ischemia/reperfusion injury in cultured neonatal rat cardiomyocytes.
We incubated neonatal Sprague-Dawley rat cardiomyocytes in primary culture in a medium simulating ischemia (consisting of hypoxia plus serum deprivation) for 2 h, then re-incubated them for 24 h in normal culture medium to establish a model of simulated ischemia/reperfusion (I/R) injury. Apoptotic cell death was measured by MTT assay, TUNEL staining and flow cytometry. Morphological alterations were assessed by transmission electron microscopy, the expression of caspases-3 and -9 and Bcl-2 and the release of cytochrome c by Western blotting, and the intracellular free-calcium concentration ([Ca2+]i) by laser confocal scanning microscopy. The results showed that pretreatment with 10 micromol/l spermine or spermidine significantly inhibited apoptosis in the I/R cells, suppressed the expression of caspases-3 and -9 and cytochrome c release, up-regulated Bcl-2 expression and decreased [Ca2+]i. However, pretreatment with 10 micromol/l putrescine had the opposite effects. Evidence for this "double-edged" effect of polyamines on apoptosis in I/R-injured cardiomyocytes is presented for the first time. It may suggest a novel pharmacological target for preventing and treating cardiac ischemia/reperfusion injury.
Han
Liping
L
Department of Pathophysiology, Harbin Medical University, Harbin 150086, China.
Xu
Changqing
C
Jiang
Chunming
C
Li
Hongzhu
H
Zhang
Weihua
W
Zhao
Yajun
Y
Zhang
Li
L
Zhang
Yanqiao
Y
Zhao
Weiming
W
Yang
Baofeng
B
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects*; D002118:Calcium / Q000378:metabolism; D020169:Caspases / Q000378:metabolism; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D046529:Microscopy, Electron, Transmission; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects*; D011073:Polyamines / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury
D011073:Polyamines; D019253:Proto-Oncogene Proteins c-bcl-2; D045304:Cytochromes c; D020169:Caspases; D002118:Calcium