Maresin 2, a Specialized Pro-Resolution Lipid Mediator, Reduces Pain and Inflammation Induced by Venom in Mice.

The venom of (BjV) induces intense and prolonged pain, which is not alleviated by antivenom, along with hemorrhage and inflammation. In this study, we investigated the effects of the specialized pro-resolving lipid mediator (SPM) maresin 2 (MaR2) in a murine model of BjV-evoked pain and inflammation. Mice received a single intraperitoneal (i.p.) injection of MaR2 30 min before the intraplantar BjV injection. MaR2 treatment significantly attenuated mechanical (electronic aesthesiometer) and thermal (hot plate) hyperalgesia in a dose-dependent manner. Additionally, MaR2 restored the balance for the hind-paw static weight distribution. When BjV (0.01, 0.1, and 1 μg) stimulus was administered intraperitoneally, pre-treatment with MaR2 (0.3, 1, or 3 ng) ameliorated mechanical and thermal hyperalgesia in a dose-dependent manner. Moreover, MaR2 (3 ng) effectively reduced the levels of myeloperoxidase activity and cytokines (TNF-α, IL-1β, and IL-6) and superoxide anion (O) production induced by intraplantar injection of BjV while enhancing total antioxidant levels (ABTS scavenging). For the peritonitis model induced by BjV, MaR2 pretreatment decreased leukocyte recruitment, hemorrhage, nitric oxide (NO), and O generation and gp91phox and inducible nitric oxide synthase (iNOS) mRNA expression. In conclusion, this study presents the first evidence that MaR2 effectively mitigated BjV-induced pain, hemorrhage, and inflammation.