Resolvins are a group of polyhydroxylated metabolites of docosahexaenoic acid (DHA) found in the inflammatory exudates of aspirin-treated experimental animals. 17(R)-HDHA is the primary oxygenation product of DHA when exposed to aspirin-inhibited cyclooxygenase-2. 17(R)-HDHA serves as a precursor to resolvins and has intrinsic biological activity, such as the inhibition of TNFα-induced IL-1β expression in human glioma cells.
17(R)-Resolvin D3 (17(R)-RvD3) is an aspirin-triggered epimer of resolvin D3, produced from docosahexaenoic acid (DHA) through the action of COX-2 in the presence of aspirin, via a 17(R)-hydroperoxy DHA (17(R)-HDHA) intermediary. Identified in mouse inflammatory exudates, 17(R)-RvD3 notably inhibits the transmigration of isolated human polymorphonuclear cells (PMNs) and fosters the efferocytosis of apoptotic PMNs by macrophages. Furthermore, in a mouse model of zymosan-induced peritonitis, 17(R)-RvD3 administration (10 ng animal) significantly curtails neutrophil infiltration into the peritoneal cavity and modulates cytokine levels by reducing IL-6 and increasing IL-10 in the inflammatory exudate. It engages GPR32, evidenced by activation in a β-arrestin reporter assay and augments phagocytosis more effectively in CHO cells overexpressing GPR32 compared to controls. Additionally, 17(R)-RvD3 enhances the clearance of etoposide-induced tumor cell debris by monocyte-derived macrophages in H460 human lung carcinoma.