Leukotriene B₄ Metabolism and p70S6 Kinase 1 Inhibitors: PF-4708671 but Not LY2584702 Inhibits CYP4F3A and the ω-Oxidation of Leukotriene B₄ In Vitro and In Cellulo

Autor: Cyril Martin, Anne-Sophie Archambault, Caroline Turcotte, Michel Laviolette, Véronique Provost, Julie S. Lefebvre, Nicolas Flamand
Rok vydání: 2016
Předmět:
0301 basic medicine
Leukotriene B4
Neutrophils
Kinase Inhibitors
lcsh:Medicine
Pathology and Laboratory Medicine
Biochemistry
Piperazines
chemistry.chemical_compound
White Blood Cells
Animal Cells
Medicine and Health Sciences
Enzyme Inhibitors
lcsh:Science
Immune Response
Liquid Chromatography
Multidisciplinary
Chromatographic Techniques
Imidazoles
Ribosomal Protein S6 Kinases
70-kDa

hemic and immune systems
respiratory system
lipids (amino acids
peptides
and proteins)

Cellular Types
Oxidation-Reduction
Research Article
Noncompetitive Inhibitors
Immune Cells
Inflammatory Diseases
Immunology
Biology
Biosynthesis
Research and Analysis Methods
03 medical and health sciences
Enzyme activator
Signs and Symptoms
In vivo
Diagnostic Medicine
Humans
Cytochrome P450 Family 4
Protein Kinase Inhibitors
PI3K/AKT/mTOR pathway
Inflammation
Blood Cells
lcsh:R
Biology and Life Sciences
Lipid signaling
Metabolism
Cell Biology
In vitro
biological factors
High Performance Liquid Chromatography
respiratory tract diseases
Enzyme Activation
030104 developmental biology
chemistry
Enzymology
lcsh:Q
Zdroj: PLoS ONE
PLoS ONE, Vol 12, Iss 1, p e0169804 (2017)
ISSN: 1932-6203
Popis: LTB4 is an inflammatory lipid mediator mainly biosynthesized by leukocytes. Since its implication in inflammatory diseases is well recognized, many tools to regulate its biosynthesis have been developed and showed promising results in vitro and in vivo, but mixed results in clinical trials. Recently, the mTOR pathway component p70S6 kinase 1 (p70S6K1) has been linked to LTC4 synthase and the biosynthesis of cysteinyl-leukotrienes. In this respect, we investigated if p70S6K1 could also play a role in LTB4 biosynthesis. We thus evaluated the impact of the p70S6K1 inhibitors PF-4708671 and LY2584702 on LTB4 biosynthesis in human neutrophils. At a concentration of 10 μM, both compounds inhibited S6 phosphorylation, although neither one inhibited the thapsigargin-induced LTB4 biosynthesis, as assessed by the sum of LTB4, 20-OH-LTB4, and 20-COOH-LTB4. However, PF-4708671, but not LY2584702, inhibited the ω-oxidation of LTB4 into 20-OH-LTB4 by intact neutrophils and by recombinant CYP4F3A, leading to increased LTB4 levels. This was true for both endogenously biosynthesized and exogenously added LTB4. In contrast to that of 17-octadecynoic acid, the inhibitory effect of PF-4708671 was easily removed by washing the neutrophils, indicating that PF-4708671 was a reversible CYP4F3A inhibitor. At optimal concentration, PF-4708671 increased the half-life of LTB4 in our neutrophil suspensions by 7.5 fold, compared to 5 fold for 17-octadecynoic acid. Finally, Michaelis-Menten and Lineweaver-Burk plots indicate that PF-4708671 is a mixed inhibitor of CYP4F3A. In conclusion, we show that PF-4708671 inhibits CYP4F3A and prevents the ω-oxidation of LTB4 in cellulo, which might result in increased LTB4 levels in vivo.
Databáze: OpenAIRE