Protectin D1-d5 is 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 .1 DHA 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 generated in vitro during macrophage-apoptotic interactions.2 It 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.3 It 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)