Cellular glutathione peroxidase as a predominant scavenger of hydroperoxyeicosatetraenoic acids in rabbit alveolar macrophages.
The cytosol of rabbit lung alveolar macrophages contains a high amount of peroxidase, which reduces 5-hydroperoxyeicosatetraenoic acid (5-HPETE) to 5-hydroxyeicosatetraenoic acid (5-HETE) in the presence of glutathione. This peroxidase was purified 69-fold to homogeneity with overall recovery of activity of 18.5%. The molecular mass of the enzyme was approximately 80 kDa by gel filtration, and emerged as a single band at 23.1 kDa under reducing condition by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The amino-terminal sequence of the purified peroxidase was completely identical to the sequence deduced from cellular glutathione peroxidase (cGPx) gene of rabbit liver. No other activity that reduces 5-HPETE to 5-HETE was observed during purification. These results suggest that cGPx plays an important role in metabolism of lipid hydroperoxides, especially HPETE, in lung alveolar macrophages.
Chiba
N
N
Japan Energy Research Center Co., Ltd., Tokyo.
Imai
H
H
Narashima
K
K
Arai
M
M
Oshima
G
G
Kunimoto
M
M
Nakagawa
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D005979:Glutathione Peroxidase / Q000378:metabolism*; D066298:In Vitro Techniques; D015289:Leukotrienes / Q000378:metabolism*; D016676:Macrophages, Alveolar / Q000201:enzymology* / Q000378:metabolism; D008969:Molecular Sequence Data; D011817:Rabbits; D017421:Sequence Analysis
D015289:Leukotrienes; C047629:8-hydroperoxyeicosatetraenoic acid; D005979:Glutathione Peroxidase