Antioxidant and anti-inflammatory activities of the phenolic extracts of Sapium sebiferum (L.) Roxb. leaves

Ethnopharmacological relevance: The leaves of Sapium sebiferum have long been used in Traditional Chinese Medicine (TCM) for the treatment of eczema, shingles, edema, swelling, ascites, scabs, and snakebites, among other maladies. Aim of this study: The present study aimed to investigate the antioxidant and anti-inflammatory effects of the phenolic extracts of Sapium sebiferum leaves using in vitro and in vivo models. Materials and methods: The in vitro antioxidant activities of the extracts were measured using common chemical methods (total phenolic content; total flavonoid content; scavenging of DPPH center dot, ABTS+center dot, superoxide, and nitrite radicals; reducing power; beta-carotene bleaching; and FTC assays). The in vivo topical anti-inflammatory activities were tested using the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced dermatitis animal model. The SOD and CAT activities and the GSH content of ear tissue were also determined using test kits. Results: The extracts of Sapium sebiferum leaves exhibited strong in vitro antioxidant activities. They also showed significant (P < 0.001) and dose-dependent anti-inflammatory activities in an acute dermatitis model at the doses of 0.03 mg/ear, 0.1 mg/ear, and 0.3 mg/ear. The application of Sapium sebiferum leaf extracts increased the SOD and CAT activities and the GSH content relative to those of the TPA treatment group. The anti-inflammatory effect of the Sapium sebiferum leaf extract was positively correlated with its antioxidant activity. Conclusion: These results demonstrate that Sapium sebiferum leaf extract is an effective anti-inflammatory agent in the TPA-induced dermatitis model, and its anti-inflammatory effect is related, at least in part, to its antioxidant activity. (C) 2013 Elsevier Ireland Ltd. All rights reserved.