Date Taro, Belanger Adam J, Mochizuki Seibu, Sullivan Jennifer A, Liu Louis X, Scaria Abraham, Cheng Seng H, Gregory Richard J, Jiang Canwen
Genzyme Corporation, 31 New York Avenue, Framingham, MA 01701, USA.
Cardiovasc Res. 2002 Aug 1;55(2):309-19. doi: 10.1016/s0008-6363(02)00412-1.
This study aimed to examine the effects of adenovirus-mediated expression of p35, a baculovirus gene, on apoptosis induced by hypoxia/reoxygenation (H/R) in cardiomyocytes.
Neonatal rat cardiomyocytes were infected with recombinant adenoviral vectors expressing p35 (Ad2/CMVp35) or no transgene (Ad2/CMVEV) and were then subjected to H/R. Separate groups of non-infected cardiomyocytes were treated with pharmacological caspase inhibitors or antioxidants. Cell viability, apoptosis, caspase activity, and cellular reactive oxygen species (ROS) were measured using various assays.
H/R decreased cell viability and increased cellular ROS levels, caspase activity, and cell apoptosis. Infection with Ad2/CMVp35 effectively inhibited the increase in cellular ROS levels, the activities of caspases 3 and 8, apoptosis, and cell death following H/R, whereas Ad2/CMVEV had no effect. Despite its ability to abolish the increase in caspase activity and partially inhibit apoptosis, the pan-caspase inhibitor ZVAD-fmk (100 microM) failed to significantly reduce cell death induced by H/R. N-acetyl-L-cysteine, an antioxidant, completely inhibited H/R-induced increase in cellular ROS levels, but reduced apoptosis and cell death by 30% only.
Adenovirus-mediated expression of p35 effectively inhibits H/R-induced cardiomyocyte apoptosis by reducing cellular ROS levels and inhibiting caspase activity.