The lipoxygenase pathway has been implicated in the growth, migration, and contraction of vascular smooth muscle cells (VSMCs). However, the precise type of lipoxygenase present in the vascular wall has not been characterized. In this study, we used a specific reverse-transcriptase polymerase chain reaction method with 2 sets of specific primers on total RNA and polyA (+)RNA of normal human VSM...

Lipoxin A4 (LXA4) is a potent endogenous lipoxygenase-derived eicosanoid with antiinflammatory and proresolving properties. Supraphysiological levels of LXA4 are generated during infection by Toxoplasma gondii, which in turn reduces interleukin (IL) 12 production by dendritic cells, thus dampening Th1-type cell-mediated immune responses and host immunopathology. In the present work, we sought e...

Ferrous lipoxygenases seem to be activated through a feedback control mechanism via FA hydroperoxides generated from PUFAs by partially existing ferric lipoxygenases. However, during leukotriene synthesis, feedback activation of ferrous 5-lipoxygenase in the presence of arachidonic acid (AA) was not observed. In the present study, we examined the feedback activation of ferrous 5-lipoxygenase in...

The signal molecules that regulate pancreatic cancer growth are still poorly understood. We have previously reported that 5-lipoxygenase not expressed in normal pancreatic ductal cells, but was markedly upregulated and involved cell proliferation and survival in human pancreatic cancer. Pancreatic cancer cells produce a large amount of growth factors, which are important for maintaining pancrea...

The ability of 19 structural analogs of propyl gallate to inhibit purified soybean seed (Glycine max [L.] Merr. var. Ransom) lipoxygenase-2 (EC 1.13.11.12) was determined. The results indicate that the o-dihydroxy and not the ester function of propyl gallate is essential for inhibition of lipoxygenase. Catechol thus represents the minimum inhibitory structure. Among those compounds possessing a...

Leukotrienes are lipid messengers involved in autocrine and paracrine cellular signaling. They are synthesized from arachidonic acid by the 5-lipoxygenase pathway. Current models of this enzymatic pathway recognize that a key step in initiating leukotriene synthesis is the calcium-mediated movement of enzymes, including 5-lipoxygenase, to intracellular membranes. However, 5-lipoxygenase can be ...

in the recent years, the role of lox enzymes in the cause of neoplastic diseases such as colorectal, skin, pancreatic and renal cancers has been confirmed. a new series of 1,3,4-thiadiazole derivatives bearing 2-pyridyl moiety was synthesized and their cytotoxicity was assessed using mtt protocol. enzyme inhibitory activity of prepared compounds was also tested against 15-lipoxygenase-1 as nove...

OBJECTIVE Vasorelaxation of rabbit aorta is mediated by factors released from the vascular endothelium. In the aortic endothelium, arachidonic acid (AA) is metabolized via the 15-lipoxygenase pathway to the vasodilatory compounds 11,12,15-trihydroxyeicosatrienoic acid (THETA) and 15-hydroxy-11,12-epoxyeicosatrienoic acid (HEETA). Interleukin-13 (IL-13) increases 15-lipoxygenase expression and a...

Interleukin-13 and interferon-γ are important effectors of T-helper cells. Interleukin-13 increases expression of the arachidonic acid-metabolizing enzyme, 15-lipoxygenase-1, in a variety of cell types. 15-lipoxygenase-1 is dramatically elevated in the airways of subjects with asthma. Studies in animals indicate that 15-lipoxygenase-1 contributes to the development of allergic airway inflammati...