Selective incorporation of ( sup 15 S)-hydroxyeicosatetraenoic acid in phosphatidylinositol of human neutrophils: Agonist-induced deacylation and transformation of stored hydroxyeicosanoids

Journal Article · Wed Aug 01 00:00:00 EDT 1990 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.87.16.6248· OSTI ID:6621195

Brezinski, M E; Serhan, C N ^[1]

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1. Brigham and Women's Hospital, Boston, MA (USA)

The uptake and mobilization of (15S)-hydroxy-5,8,11-cis-13-trans-eicosatetraenoic acid (15-HETE), a major product of arachidonic acid metabolism, was examined with human neutrophils. Upon exposure to labeled 15-HETE, PMNs rapidly (15 sec to 20 min) incorporated approximately 20% of the label into phosphatidylinositol, while less than 4% was associated with other phospholipid classes and neutral lipids. This pattern was distinct from that of either labeled arachidonate or labeled(5S)-hydroxy-8,11,14-cis-6-trans-eicosatetraenoic acid (5-HETE), which within 20 min were predominantly associated with triglycerides and phosphatidylcholine. After reversed-phase HPLC, greater than 98% of the label in phosphatidylinositol, isolated from PMNs, was released with phospholipase A2. Upon exposure to either chemotactic peptide (FMLP), phorbol 12-myristate 13-acetate, or an ionophore (A23187), 15-HETE-labeled PMNs released 15-HETE from phosphatidylinositol and displayed an impaired ability to generate leukotriene B4 (LTB4), 20-OH-LTB4, and 20-COOH-LTB4. Deacylated (3H)15-HETE was converted to (5S,15S)-dihydroxy-6,13-trans-8,11-cis-eicosatetraenoic acid (5,15-DHETE), lipoxin A4, and lipoxin B4, each carrying 3H label. PMNs labeled with 5-HETE also released and transformed this HETE when stimulated. However, the profile of labeled products differed between PMNs with either esterified 15-HETE or 5-HETE. When activated, 5-HETE-labeled PMNs generated both 5,20-DHETE and 5,15-DHETE but not labeled lipoxins. Threshold aggregation induced by FMLP with 15-HETE-labeled PMNs was inhibited, while the threshold response was relatively unimpaired with either A23187 or phorbol 12-myristate 13-acetate-induced aggregation. Results indicate that 15-HETE is esterified into phosphatidylinositol of PMNs, which can be mobilized and transformed upon exposure of the cells to a second signal.

• OSTI ID: 6621195
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (USA) Vol. 87:16; ISSN 0027-8424; ISSN PNASA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
560300 -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
ARACHIDONIC ACID
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIOSYNTHESIS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARBOXYLESTERASES
CARBOXYLIC ACIDS
CARCINOGENS
CHEMICAL REACTIONS
CHROMATOGRAPHY
EICOSANOIC ACID
ENZYMES
ESTERASES
ESTERIFICATION
ESTERS
HYDROGEN COMPOUNDS
HYDROLASES
IN VITRO
ISOTOPE APPLICATIONS
ISOTOPE DILUTION
LEUKOCYTES
LIPASES
LIPIDS
LIQUID COLUMN CHROMATOGRAPHY
MAMMALS
MAN
MATERIALS
METABOLISM
MONOCARBOXYLIC ACIDS
NEUTROPHILS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHORBOL ESTERS
PHOSPHOLIPIDS
PRIMATES
SEPARATION PROCESSES
SYNTHESIS
TRACER TECHNIQUES
TRIGLYCERIDES
TRITIUM COMPOUNDS
UPTAKE
VERTEBRATES