Calcium ionophore enables soluble agonists to stimulate macrophage 5-lipoxygenase.

Transient exposure to calcium ionophore enables in vitro fertilization in sterile mouse models

Mammalian sperm acquire fertilizing capacity in the female tract in a process called capacitation. At the molecular level, capacitation requires protein kinase A activation, changes in membrane potential and an increase in intracellular calcium. Inhibition of these pathways results in loss of fertilizing ability in vivo and in vitro. We demonstrated that transient incubation of mouse sperm with...

Inhibition of alveolar macrophage 5-lipoxygenase metabolism by auranofin.

We have examined the effect of the oral gold compound auranofin (AF) on calcium ionophore A23187-induced arachidonic acid metabolism in the rat alveolar macrophage. Both reverse-phase high performance liquid chromatographic and radioimmunoassay analyses revealed that AF dose-dependently inhibited leukotriene B4 and 5-hydroxyeicosatetraenoic acid synthesis in a parallel fashion with an IC50 appr...

5-Hydroxyeicosanoids selectively stimulate the human neutrophil 15- lipoxygenase to use endogenous substrate

When human neutrophils, prelabeled with [3H]arachidonic acid, were incubated with 5S,15S-dihydroxyeicosatetraenoic acid (5,15-diHETE), a dose-dependent increase in the 15-lipoxygenase product [3H]-15-HETE was observed relative to untreated cells. Typically, a fivefold increase in [3H]-15-HETE formation was obtained upon exposure of these cells to 3 muM 5,15-diHETE. There was no appreciable enha...

5-Lipoxygenase metabolites of arachidonic acid stimulate isolated osteoclasts to resorb calcified matrices.

Bone resorption requires cooperation between osteoclasts and mononuclear accessory cells by mechanisms which have not been elucidated. Since multinucleated cells in giant cell tumors of bone have many phenotypic and functional characteristics of normal osteoclasts, we have examined the interaction between the bone-resorbing multinucleated cells and the distinct mononuclear stromal cells from th...

TLR Agonists Stimulate Nlrp3-Dependent