Prevention of geranylgeranoic acid-induced apoptosis by phospholipid hydroperoxide glutathione peroxidase gene.
Micromolar concentrations (0.5 approximately 5 microM) of all-trans geranylgeranoic acid (GGA) induced cell death in a guinea pig cell line, 104C1, whereas under the same conditions GGA was unable to kill 104C1/O4C, a clone established from 104C1 cells by transfection of them with the human phospholipid hydroperoxide glutathione peroxidase (PHGPx) gene. GGA (5 microM) induced a loss of the mitochondrial inner membrane potential (DeltaPsim) in 104C1 cells in 2 h, and their apoptotic cell death became evident in 6 h. On the other hand, 104C1/O4C cells were resistant to loss of DeltaPsim and showed intact morphology until at least 24 h after addition of 10 microM GGA. Dihydroethidine, superoxide-sensitive probe, was immediately oxidized 15 min after addition of GGA in both 104C1 and 104C1/O4C cells. The peroxide-sensitive probe 2',7'-dichlorofluorescin diacetate (H2-DCF-DA) was strongly oxidized in 104C1 cells 4 h after the addition of 2.5 microM GGA, but not in 104C1/O4C cells even in the presence of 10 microM GGA. The present results suggest that GGA induced a hyper-production of superoxide and subsequently peroxides, which in turn may have led to dissipation of the DeltaPsim and final apoptotic cell death in 104C1 cells.
Shidoji
Yoshihiro
Y
Molecular and Cellular Biology, Graduate School of Human Health Sciences, Siebold University of Nagasaki, Nagayo, Nagasaki 851-2195, Japan. shidoji@sun.ac.jp
Okamoto
Kyoko
K
Muto
Yasutoshi
Y
Komura
Sadaaki
S
Ohishi
Nobuko
N
Yagi
Kunio
K
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004224:Diterpenes / Q000494:pharmacology*; D005979:Glutathione Peroxidase / Q000235:genetics*; D006168:Guinea Pigs; D008856:Microscopy, Fluorescence; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase
D004224:Diterpenes; C040155:geranylgeranic acid; D000080662:Phospholipid Hydroperoxide Glutathione Peroxidase; D005979:Glutathione Peroxidase