Abstract:
:Lipoxin B (LXB) was prepared by incubation of (15S)-15-hydroperoxy-5,8,11-cis-13-trans-icosatetraenoic acid (15-HPETE) with human leukocytes. Comparison with a number of trihydroxyicosatetraenes prepared by total synthesis showed that biologically derived LXB is (5S,14R,15S)-5,14,15-trihydroxy-6,10,12-trans-8-cis-icosatetraenoi c acid. Two isomers of LXB were identified by using an improved isolation procedure. These compounds were shown to be (5S,14R,15S)-5,14,15-trihydroxy-6,8,10,12-trans-icosatetraenoic acid (8-trans-LXB) and (5S,14S,15S)-5,14,15-trihydroxy-6,8,10,12-trans-icosatetraenoic acid [(14S)-8-trans-LXB]. Experiments with 18O2 showed that formation of LXB and its two isomers occurred with incorporation of molecular oxygen at C-5 but not at C-14. These results together with the finding that (15S)-hydroxy-5,8,11-cis-13-trans-icosatetraenoic acid (15-HETE) is a precursor of LXB compounds in activated leukocytes suggest that 15-hydroxy-5,6-epoxy-7,9,13-trans-11-cis-icosatetraenoic acid or its equivalent is a common intermediate in the biosynthesis of LXB and its two isomers.
journal_name
Proc Natl Acad Sci U S Aauthors
Serhan CN,Hamberg M,Samuelsson B,Morris J,Wishka DGdoi
10.1073/pnas.83.7.1983subject
Has Abstractpub_date
1986-04-01 00:00:00pages
1983-7issue
7eissn
0027-8424issn
1091-6490journal_volume
83pub_type
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