MCTR3

Maresin conjugates in tissue regeneration 3 (MCTR3) is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid (DHA; ) in macrophages.^1,2 DHA is oxidized to maresin 1 (MaR1; ), which is converted to MCTR1 by glutathione S-transferase Mu 4 or leukotriene C₄ synthase, then to MCTR2 by γ-glutamyl transferase, and to MCTR3 by dipeptidase.³ MCTR3 accelerates tissue regeneration in planaria (1 and 100 nM) approximately as potently as MCTR2 and more potently than MCTR1.² Pretreatment with MCTR3 prior to E. coli administration in mice reduces neutrophil infiltration, shortens the inflammatory resolution period, and increases phagocytosis of E. coli by macrophages. When administered at a dose of 100 ng 12h post E. coli infection in a mouse model of peritonitis, MCTR3 selectively reduces the amount of the eicosanoids PGD₂ , PGE₂ , PGF_2α , and TXB₂ in the exudate.