PAF C-18:1 is a naturally occurring phospholipid produced by cells upon stimulation and plays a role in the establishment and maintenance of the inflammatory response. It is less potent than PAF C-16 and PAF C-18 in the induction of neutrophil chemotaxis, but is equipotent to PAF C-16 and PAF C-18 in promoting eosinophil migration. PAF C-18:1 activates the PAF receptor and has been used in antibody binding experiments to determine the importance of an acyl linkage at the sn-2 position for recognition at this receptor.
PAF C-16 is a naturally occurring phospholipid produced upon stimulation through two distinct pathways known as the remodeling and 'de novo' pathways. It is a potent mediator of neutrophil migration and the production of reactive oxygen species and IL-6. Pathological processes involving PAF include necrotizing enterocolitis
2-O-methyl PAF C-16 is a synthetic analog of platelet-activating factor (PAF) featuring a methyl group attached via an ether linkage at the sn-2 position. While the specific biological activities of 2-O-methyl PAF C-16 remain undercharacterized, studies with its C-18 counterpart have demonstrated its ability to modulate various biological processes. These processes include reducing plasma membrane fluidity and hindering the invasiveness of tumor cells in embryonic chick hearts. Furthermore, in rat astrocytes, the C-18 analog prompts the release of significant amounts of nitric oxide (NO) through a mechanism that involves the activation of nitric oxide synthase (NOS).
Oxidized low-density lipoprotein (oxLDL) encompasses low molecular weight entities that facilitate monocyte differentiation and activate polymorphonuclear leukocytes. A substance, recently isolated and purified from oxLDL and identified as azelaoyl PC, exemplifies this. Similarly, Butanoyl PAF, a compound closely related to azelaoyl PC, maintains over 10% of the agonist potency of platelet-activating factor (PAF). Notably, Butanoyl PAF's concentration in oxLDL surpasses that of enzymatically generated PAF by more than 100-fold, making it a significant signalling molecule within oxLDL.