Docosapentaenoic acid derived metabolites and mediators-the new world of lipid mediator medicine in a nutshell

Recent years have seen the description and elucidation of a new class of anti-inflammatory and pro-resolving lipid mediators. The arachidonic acid (AA)-derived compounds in this class are called lipoxins and have been described in great detail since their discovery thirty years ago. The new players are mediators derived from fish oil omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), called resolvins, protectins and maresins. Taken together, these mediators are also called specialized pro-resolution mediators (SPMs). As compared to the AA/EPA/DHA-derived compounds, research regarding mediators formed from the n-3 and n-6 docosapentaenoic acids (DPAn-3 and DPAn-6) is sparse. However, mono- di- and trihydroxy derivates of the DPAs have anti-inflammatory properties as well, even though mechanisms of their anti-inflammatory action have not been fully elucidated. This review aims to summarize current knowledge regarding the DPA-derived SPMs and their actions.