11-trans LeukotrieneC4 (11-trans LTC4) is a C-11 double bond isomer of LTC4. LTC4 undergoes slow temperature-dependent isomerization to 11-trans LTC4 during storage. 11-trans LTC4 is produced in smaller amounts relative to LTC4 in ionophore-stimulated HMC-1 cells (a human mast cell line) and equine eosinophils, but not in human neutrophils or RBL-1 cells. It is nearly equipotent with LTC4 for contraction of guinea pig parenchymal and ileum. In a radioligand binding assay using guinea pig ileum as a cysteinyl leukotriene receptor preparation, the pKis for LTC4 and 11-trans LTC4 were determined to be 6.42 and 6.58, respectively.
LeukotrieneC4 (LTC4) is the parent cysteinyl-leukotriene produced by the LTC4 synthase-catalyzed conjugation of glutathione to LTA4. LTC4 is produced by neutrophils, macrophages, and mast cells, and by transcellular metabolism in platelets. It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A) and exhibits potent smooth muscle contracting activity. LTC4-induced bronchoconstriction and enhanced vascular permeability contribute to the pathogenesis of asthma and acute allergic hypersensitivity. The concentration of LTC4 required to produce marked contractions of lung parenchymal strips and isolated tracheal rings is about 1 nM. LTC4 methyl ester is a more lipid soluble form of LTC4. The biological activity of LTC4 methyl ester has not been reported.
Produced by neutrophils, macrophages, mast cells, and by transcellular metabolism in platelets, leukotrieneC4 (LTC4) is the parent cysteinyl leukotriene formed by the LTC4 synthase-catalyzed conjugation of glutathione to LTA4. It is one of the constituents of slow-reacting substance of anaphylaxis (SRS-A) and exhibits potent smooth muscle contracting activity. LTC4, however, is rapidly metabolized to LTD4 and LTE4, which makes the characterization of LTC4 pharmacology difficult. N-methyl LeukotrieneC4 (N-methyl LTC4) is a synthetic analog of LTC4 that is not readily metabolized to LTD4 and LTE4.It acts as a potent and selective CysLT2 receptor agonist exhibiting EC50 values of 122 and > 2,000 nM at the human CysLT2 and CysLT1 receptors, respectively. It has essentially the same potency as LTC4 at both the human and murine receptors CysLT2 receptors. N-methyl LTC4 is potent and active in vivo, causing vascular leak in mice overexpressing the human CysLT2 receptor but not in CysLT2 receptor knockout mice.
LeukotrieneC4 (14,15-LTC4) is an inflammatory mediator synthesized from arachidonic acid through the actions of 15- and 12-lipoxygenases (LOs), involving intermediates such as 15-HpETE and 14,15-LTA4. Unlike the majority of leukotrienes formed via the 5-LO pathway, 14,15-LTC4 is an eoxin predominantly produced by eosinophils, although mast cells and nasal polyps can also synthesize it. While its physiological roles are not well understood, 14,15-LTC4 exhibits limited contractile activity on guinea pig ileum and pulmonary parenchyma. However, it can increase vascular permeability in human endothelial cell monolayers in vitro with potency comparable to 5-LO-derived leukotrienes, contributing to plasma leakage characteristic of inflammation.
(S)-Verapamil hydrochloride is an inhibitor of leukotrieneC4 (LTC4) and calcein transport by MRP1,and leads to the death of potentially resistant tumor cells.
Verlukast is an (R)-enantiomer of MK-571 and a potent and selective LTD4 receptor antagonist. Verlukast showed [3H]leukotriene D4 binding in guinea-pig (IC50 = 3.1 +/- 0.5 nM) and human (IC50 = 8.0 +/- 3.0 nM) lung homogenates and dimethyl sulfoxide diffe
Maresin conjugates in tissue regeneration 1 (MCTR1) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is then converted to MCTR1 by glutathione S-transferase Mu 4 or leukotrieneC4 synthase. MCTR1 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR1 (50 ng mouse, i.p.) prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR1 reduces the amount of eicosanoids in the exudate.
Maresin conjugates in tissue regeneration 2 (MCTR2) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages at the site of inflammation. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotrieneC4 synthase then to MCTR2 by γ-glutamyl transferase. MCTR2 accelerates tissue regeneration in planaria (1 and 100 nM). Pretreatment with MCTR2 prior to E. coli administration reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR2 selectively reduced the amount of the eicosanoids PGD2 and PGF2α in the exudate.
Maresin conjugates in tissue regeneration 3 (MCTR3) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid in macrophages. DHA is oxidized to maresin 1 , which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotrieneC4 synthase, then to MCTR2 by γ-glutamyl transferase, and to MCTR3 by dipeptidase. MCTR3 accelerates tissue regeneration in planaria (1 and 100 nM) approximately as potently as MCTR2 and more potently than MCTR1. Pretreatment with MCTR3 prior to E. coli administration in mice reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR3 selectively reduces the amount of the eicosanoids PGD2 , PGE2 , PGF2α , and TXB2 in the exudate.
FTY720, an immune modulator, down-regulates sphingosine-1-phosphate (S1P) receptors, enhances the activity of sphingosine transporter Abcb1 and leukotrieneC4 transporter Abcc1, and inhibits cytosolic phospholipase A2 activity. Its efficacy relies on in vivo phosphorylation by sphingosine kinases, resulting in FTY720-phosphate which also down-regulates S1P receptors. NBD-FTY720, a fluorescently-labeled analog of FTY720, retains the hydroxy methyl side chain targeted for phosphorylation, suggesting potential phosphorylation in vivo.
1,6-O,O-Diacetylbritannilactone(OODBL) has anti-inflammatory activity, it has a potential therapeutic efficacy on inflammatory diseases especially allergic airway disease as a lead compound. OODBL has anti-asthmatic activity, it reduces leukotrieneC4 pro