Protectin D1-d₅is intended for use as an internal standard for the quantification of protectin D1 by GC- or LC-MS. Protectin D1 is a specialized pro-resolving mediator (SPM) synthesized from docosahexaenoic acid .¹DHA is oxidized to 16S,17S-epoxy protectin, which is converted to protectin D1 enzymatically. Protectin D1 increases phagocytosis of apoptotic polymorphonuclear leukocytes (PMNs) by macrophages in a non-phlogistic manner and is generatedin vitroduring macrophage-apoptotic interactions.²It enhances phagocytosis in mice after 24 hours, but not at the initiation or peak of inflammation. It also decreases PMN infiltration in a zymosan-induced mouse model of inflammation when administered at a dose of 300 ng per animal. Protectin D1 (200 µg, i.v.) inhibits increases in neutrophil counts in bronchoalveolar fluid (BALF) and lung myeloperoxidase activity in a mouse model of pulmonary injury and inflammation induced by intratracheal LPS instillation.³It also decreases pulmonary edema and promotes neutrophil apoptosis in BALF.

1.Rodriguez, A.R., and Spur, B.W.Total synthesis of pro-resolving and tissue-regenerative protectin sulfido-conjugatesTetrahedron Lett.56(42)5811-5815(2015) 2.Schwab, J.M., Chiang, N., Arita, M., et al.Resolvin E1 and protectin D1 activate inflammation-resolution programmesNature447(7146)869-874(2007) 3.Li, X., Li, C., Liang, W., et al.Protectin D1 promotes resolution of inflammation in a murine model of lipopolysaccharide-induced acute lung injury via enhancing neutrophil apoptosisChin. Med. J. (Engl.)127(5)810-814(2014)