Possible Interaction: Arachidonic Acid and Leukotriene B4

“The substance has been shown to modulate arachidonic acid metabolism by enhancing the production and release of prostacyclin and prostaglandin E2 from tissues and whole blood, and inhibiting leukotriene B4 generation in leukocytes.”

“Production of LTB4 by trichomonads was time dependent and increased twofold when arachidonic acid (100 microM) was added but was not decreased when eicosanoid inhibitors were present.”

“ LTB4 stimulation of arachidonic acid incorporation into PI was greater than into PC, whereas the stimulation of palmitic acid but not by arachidonic acid.”

“When peripheral and synovial PMNs from the same RA patient were compared, arachidonic acidinduced LTB4 synthesis in synovial fluid PMNs was increased 1.7–7.2 fold, whereas the response to Ca ionophore A23187 stimulation was similar.”

“Production of 5-hydroxy-6,8,11,14-eicosatetraenoic acid and release of free arachidonic acid were also dose-dependently inhibited by exogenous LTB4.”

“Microsomal 20-OH LTB4 formation was also inhibited 30% by arachidonic acid , a known CYP4F2 substrate, and 50% by prostaglandin A1 but was unaffected by lauric acid, palmitic acid, and PGF2alpha.”

“The addition of AA dose-dependently reversed the H23-induced inhibition of LTB4 , 5-HETE, and 12-HETE production by PMN, suggesting inhibition at the phospholipase A2 (PLA2) level.”

“These data demonstrate that [3H]LTB4 binding to PMNL is decreased by PLD-derived lipids and suggests that intracellular arachidonic acid may modulate PMNL responsiveness to LTB4 activation.”

“When arachidonic acid was added to the cell suspension, it significantly stimulated LTB4 synthesis, especially in patients with active disease.”

“We observed a pronounced inhibition of the formation of leukotriene B4 and 5-hydroxyeicosatetraenoic acid from either added [1-14C] or endogenously liberated arachidonic acid.”