Objective:To evaluate the efficacy of boswellic acid against monosodium urate crystal-induced inflammation in mice.Methods:The mice were divided into four experimental groups.GroupⅠserved as control;mice in groupⅡwere injected with monosodium urate crystal;groupⅢconsisted of monosodium urate crystal-induced mice who were treated with boswellic acid(30mg/kg/b.w.);groupⅣcomprised monosodium urate crystal-induced mice who were treated with indomethacin(3mg/kg/b.w.).Paw volume and levels/activities of lysosomal enzymes,lipid peroxidation,anti-oxidant status and inflammatory mediator TNF-αwere determined in control and monosodium urate crystal-induced mice.In addition,the levels ofβ-glucuronidase and lactate dehydrogenase were also measured in monosodium urate crystal-incubated polymorphonuclear leucocytes(PMNL)in vitro.Results:The activities of lysosomal enzymes,lipid peroxidation,and tumour necrosis factor-αlevels and paw volume were increased significantly in monosodium urate crystal-induced mice,whereas the activities of antioxidant status were in turn decreased.However,these changes were modulated to near normal levels upon boswellic acid administration.In vitro,boswellic acid reduced the level ofβ-glucuronidase and lactate dehydrogenase in monosodium urate crystal-incubated PMNL in concentration dependent manner when compared with control cells.Conclusions:The results obtained in this study further strengthen the anti-inflammatory/antiarthritic effect of boswellic acid,which was already well established by several investigators. Objective: To evaluate the efficacy of boswellic acid against monosodium urate crystal-induced inflammation in mice. Methods: The mice were divided into four experimental groups. Group I regulated as control; mice in group II were injected with monosodium urate crystal; group IIIconsisted of monosodium urate crystal-induced mice who were treated with boswellic acid (30 mg / kg / bw); group IV comprised monosodium urate crystal-induced mice who were treated with indomethacin (3 mg / kg / bw). Paw volume and levels / activities of lysosomal enzymes, lipid peroxidation, anti- oxidant status and inflammatory mediator TNF-αwere determined in control and monosodium urate crystal-induced mice. In addition, the levels of β-glucuronidase and lactate dehydrogenase were also measured in monosodium urate crystal-laid polymorphonuclear leucocytes (PMNL) in vitro. Results: The activities of lysosomal enzymes, lipid peroxidation, and tumor necrosis factor-α levels and paw volume were increased significantly in monosodium urate crystal-induced mice, whereas the activities of antioxidant status were in turn decreased. Despite these changes were modulated to near normal levels upon boswellic acid administration.In vitro, boswellic acid reduced the level of β- glucuronidase and lactate dehydrogenase in monosodium urate crystal- induced PMNL in concentration dependent manner when compared with control cells. Conclusions: The results obtained in this study further strengthen the anti-inflammatory / antiarthritic effect of boswellic acid, which was already well established by several investigators.