Profiling in resolving inflammatory exudates identifies novel anti-inflammatory and pro-resolving mediators and signals for termination.

A highly orchestrated inflammatory response and its completion, termed resolution, are essential for ongoing health. Thus, complete understanding of the cellular and molecular events that govern natural resolution is vital. Using an unbiased systems approach to profile self-limited inflammatory exudates, we identified a novel genus of specialized pro-resolving lipid mediators (SPMs) comprised of three new families coined the resolvins, protectins and most recently the maresins biosynthesized from omega-3 fatty acids. These join the lipoxin- and aspirin-triggered lipoxins as anti-inflammatory and pro-resolving lipid mediators formed from arachidonic acid with the genus. SPMs have proven stereoselective, and control both the duration and magnitude of inflammation. Mapping these endogenous resolution circuits provides new avenues to probe the molecular basis of many widely occurring diseases where uncontrolled inflammation is characteristic. The focus of this JIM review is to depict recent advances from studies by the authors and colleagues on the biosynthesis and actions of these novel anti-inflammatory, pro-resolving and protective lipid mediators. Together these findings indicate that defective mechanisms and pathways in resolution may underlie our current appreciation of the inflammatory phenotype(s) that characterize some prevalent human diseases.