Myristic acid reduces skin inflammation and nociception.

This study evaluated the inhibitory effect of myristic acid (MA) on models of inflammation and nociception. The in vitro anti-inflammatory activities of MA were assessed on LPS-stimulated macrophages, membrane stabilization assay, and inhibition of protein denaturation, whereas the inhibitory activity of MA on in vivo inflammation was assessed on TPA-induced ear edema using acute and chronic assays in mice. The inhibitory effect of MA on nociception was assessed using three in vivo models. MA exerted in vitro anti-inflammatory activity by the increase (58%) in the production of IL-10 in LPS-stimulated macrophages. In the in vivo assay, MA showed good anti-inflammatory effects on the acute (ED50 = 62 mg/kg) and chronic (ED50 = 77 mg/kg) TPA-induced ear edema. The antinociceptive activity of MA was related to the participation of the nitrergic system in the formalin-induced paw licking test. PRACTICAL APPLICATIONS: Previous studies with different plant extracts containing MA, as one of their major components, have demonstrated anti-inflammatory and antinociceptive actions. However, the anti-inflammatory and antinociceptive actions of myristic acid have not been previously reported. The results suggest that MA induced anti-inflammatory effects in LPS-stimulated macrophages through the participation of IL-10. The antinociceptive effects of MA are attributed to the participation of the nitrergic system.

Anti-inflammatory activity of standardized dichloromethane extract of Salvia connivens on macrophages stimulated by LPS.

CONTEXT: A previous study demonstrated that the chloroform extract of Salvia connivens Epling (Lamiaceae) has anti-inflammatory activity. OBJECTIVE: Identification of the active components in the dicholorometane extract (DESC), and, standardization of the extract based in ursolic acid. MATERIAL AND METHODS: DESC was prepared by percolation with dichlromethane and after washed with hot hexane, its composition was determined by CG-MS and NMR, and standardized by HPLC. The anti-inflammatory activity was tested on acute TPA-induced mouse ear oedema at doses of 2.0 mg/ear. The cell viability of macrophages was evaluated by MTT method, and pro- and anti-inflammatory interleukin levels were measured using an ELISA kit. RESULTS: Ursolic acid, oleanolic acid, dihydroursolic acid and eupatorin were identified in DESC, which was standardized based on the ursolic acid concentration (126 mg/g). The anti-inflammatory activities of DESC, the acid mixture, and eupatorin (2 mg/ear) were 60.55, 57.20 and 56.40% inhibition, respectively, on TPA-induced ear oedema. The IC50 of DESC on macrophages was 149.4 µg/mL. DESC (25 µg/mL) significantly reduced TNF-α (2.0-fold), IL-1ß (2.2-fold) and IL-6 (2.0-fold) in macrophages stimulated with LPS and increased the production of IL-10 (1.9-fold). DISCUSSION: Inflammation is a basic response to injuries, and macrophages are involved in triggering inflammation. Macrophage cells exhibit a response to LPS, inducing inflammatory mediators, and DESC inhibits the biosynthesis of the pro-inflammatory and promote anti-inflammatory cytokines. CONCLUSION: DESC has an anti-inflammatory effect; reduced the levels of IL-1ß, Il-6 and TNF-α; and increases IL-10 in macrophages stimulated with LPS. Ursolic acid is a good phytochemical marker.