This study investigates the bioactive products generated from omega-3 fatty acids, specifically docosahexaenoic acid (DHA), during the resolution phase of inflammation, which is initiated by aspirin treatment. The authors report the discovery of a novel family of bioactive compounds called resolvins, which are 17R-hydroxy-containing di- and tri-hydroxy-docosanoids. These resolvins are produced in exudates from mice treated with aspirin and DHA, and they exhibit potent anti-inflammatory properties. Resolvins are generated in various cell types, including murine brain, human microglial cells, and human neutrophils, and they inhibit cytokine expression and reduce leukocytic exudates in vivo. The study also demonstrates that aspirin-acetylated cyclooxygenase-2 (COX-2) converts DHA to 17R-hydroxydocosahexaenoic acid (17R-HDHA), which is a key step in the biosynthesis of resolvins. These findings suggest that resolvins play a crucial role in dampening inflammation and promoting resolution, providing a molecular basis for the beneficial effects of omega-3 fatty acids in various diseases.This study investigates the bioactive products generated from omega-3 fatty acids, specifically docosahexaenoic acid (DHA), during the resolution phase of inflammation, which is initiated by aspirin treatment. The authors report the discovery of a novel family of bioactive compounds called resolvins, which are 17R-hydroxy-containing di- and tri-hydroxy-docosanoids. These resolvins are produced in exudates from mice treated with aspirin and DHA, and they exhibit potent anti-inflammatory properties. Resolvins are generated in various cell types, including murine brain, human microglial cells, and human neutrophils, and they inhibit cytokine expression and reduce leukocytic exudates in vivo. The study also demonstrates that aspirin-acetylated cyclooxygenase-2 (COX-2) converts DHA to 17R-hydroxydocosahexaenoic acid (17R-HDHA), which is a key step in the biosynthesis of resolvins. These findings suggest that resolvins play a crucial role in dampening inflammation and promoting resolution, providing a molecular basis for the beneficial effects of omega-3 fatty acids in various diseases.