title: Progesterone rapidly down-regulates the biosynthesis of 5-lipoxygenase products in human primary monocytes.
abstract: 5-Lipoxygenase (5-LO), the key enzyme in the biosynthesis of pro-inflammatory leukotrienes (LTs) from arachidonic acid, is regulated by androgens in human neutrophils and monocytes accounting for sex differences in LT formation. Here we show that progesterone suppresses the synthesis of 5-LO metabolites in human primary monocytes. 5-LO product formation in monocytes stimulated with Ca(2+)-ionophore A23187 or with lipopolysaccharide/formyl peptide was suppressed by progesterone at concentrations of 10-100 nM in cells from females and at 1 μM in cells from males. Progesterone down-regulated 5-LO product formation in a rapid and reversible manner, but did not significantly inhibit 5-LO activity in cell-free assays using monocyte homogenates. Also, arachidonic acid release and its metabolism to other eicosanoids in monocytes were not significantly reduced by progesterone. The inhibitory effect of progesterone on LTs was still observed when mitogen-activated protein kinases were pharmacologically blocked, stimulatory 1-oleoyl-2-acetyl-sn-glycerol was exogenously supplied, or extracellular Ca(2+) was removed by chelation. Instead, suppression of PKA by means of two different pharmacological approaches (i.e. H89 and a cell-permeable PKA inhibitor peptide) prevented inhibition of 5-LO product generation by progesterone, to a similar extent as observed for the PKA activators prostaglandin E2 and 8-Br-cAMP, suggesting the involvement of PKA. In summary, progesterone affects the capacity of human primary monocytes to generate 5-LO products and, in addition to androgens, may account for sex-specific effects on pro-inflammatory LTs.
authors: Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany. Electronic address: pergolacarlo@googlemail.com.
authors: Carlo
authors: C
authors: Pergola
authors: Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany. Electronic address: anja.schaible@gmx.de.
authors: Anja M
authors: AM
authors: Schaible
authors: Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany. Electronic address: felix.nikels@uni-jena.de.
authors: Felix
authors: F
authors: Nikels
authors: Interfakultäres Institut für Biochemie, University Tuebingen, 72076 Tuebingen, Germany. Electronic address: gabriele.dodt@uni-tuebingen.de.
authors: Gabriele
authors: G
authors: Dodt
authors: Institute for Clinical and Experimental Transfusion Medicine, University Medical Center Tuebingen, 72076 Tuebingen, Germany. Electronic address: hinnak.northoff@med.uni-tuebingen.de.
authors: Hinnak
authors: H
authors: Northoff
authors: Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University Jena, 07743 Jena, Germany. Electronic address: oliver.werz@uni-jena.de.
authors: Oliver
authors: O
authors: Werz
mesh_terms: D001094:Arachidonate 5-Lipoxygenase / Q000096:biosynthesis*; D016718:Arachidonic Acid / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D009000:Monocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D061251:Primary Cell Culture; D011374:Progesterone / Q000494:pharmacology*; D015398:Signal Transduction
chemical_list: D016718:Arachidonic Acid; D011374:Progesterone; D001094:Arachidonate 5-Lipoxygenase; D017868:Cyclic AMP-Dependent Protein Kinases; D002118:Calcium
keywords: 1-Oleoyl-2-acetyl-sn-glycerol (OAG) (PubChem CID: 6437085); 5-Lipoxygenase; 8-Br-cAMP (PubChem CID: 32014); Arachidonic acid; Ca(2+)-ionophore A23187 (PubChem CID: 11957499); Cinnamyl-3,4-dihydroxy-alpha-cyanocinnamate (CDC) (PubChem CID: 14840979); H89 (PubChem CID: 449241); Leukotriene; Monocytes; Progesterone; Prostaglandin E(2) (PubChem CID: 5280360); Sex differences; cPLA(2)α inhibitor RSC-3388, N-{(2S,4R)-4-(biphenyl-2-ylmethyl-isobutyl-amino)-1-[2-(2,4-difluorobenzoyl)-benzoyl]-pyrrolidin-2-ylmethyl}-3-[4-(2,4-dioxothiazolidin-5-ylidenemethyl)-phenyl]acrylamide (PubChem CID: 9833099)