Visit our Expo - Redox and Inflammation signaling 2012

Session XI: Cell death and cardiovascular diseases Poster XI, 4
MAPKs are activated via cPLA2 during ischaemia/reperfusion induced injury in
neonatal cardiomyocytes.
Anna-Mart Engelbrecht and Amanda Lochner.
Departments of Physiological Sciences and Medical Physiology, University of
Stellenbosch, Stellenbosch, 7600, South Africa. E-mail: ame@sun.ac.za
Myocardial ischaemia/reperfusion (I/R) injury induces death of a significant number of
cardiomyocytes and contributes to mortality. Although it has become increasingly clear that
myocardial I/R result in the death of myocytes through apoptosis, the molecular basis of this
process remains to be elucidated. Therefore, the aim of this study was to investigate the role
of cPLA2 in MAPK phosphorylation and caspase-3 cleavage in I/R-induced apoptosis in
neonatal cardiomyocytes.
Cultured neonatal cardiomyocytes were exposed to various inhibitors for 30 minutes before
the onset of 60 minutes of simulated ischaemia (induced with deoxyglucose and KCN)
followed by 30 minutes of reperfusion. Samples were analysed by Western blotting with
phospho-specific antibodies recognizing total- and phosphorylated p38 MAPK, ERK and
cPLA2. Apoptosis was determined by poly(ADP-ribose)polymerase cleavage and caspase-3
activation. Hoechst 33342 stain was used to view the morphological features of apoptosis by
fluorescence microscopy. Cell viability was measured by the MTT assay.
Inhibition of cPLA2 with AACOCF3 significantly improved cell viability during SI/R (60.17
± 1.77 to 80.17 ± 1.97%, p