Anti-inflammatory activities of Dangyuja (Citrus grandis Osbeck) in concanavalin A stimulated murine splenocytes and 12-O-tetradecanoylphorbol-13-acetate-induced murine skin edema.

Dangyuja (Citrus grandis Osbeck), a citrus cultivated in southern Korea, has been used in traditional medicine for its anti-inflammatory effect. In this study, we investigated the anti-inflammatory potential of extract of Citrus grandis Osbeck (ECGO). In in vitro assays, ECGO treatment of concanavalin A (10µg/ml, for 24h) stimulated splenocytes showed significant reduction in CD44/CD62L+ T cell population and a marked decrease in the production of inflammatory cytokines IL-2, IFN-γ and IL-4. Interestingly, in vivo assays of ECGO topical treatment (100µg/20µl/ear) significantly mitigated the TPA (4µg/20µl/ear) induced edema induction and Myeloperoxidase activity. Anti-inflammatory potential of ECGO were further evidenced through its potent decrease in expression of inducible nitric oxide, cyclooxygenase-2, IL-1ß and TNF-α and suppressed homing of CD3+ T cells and F4/80+ macrophages to site of inflammation. This study emphasizes the possibility of developing ECGO as an alternative natural topical agent to combat inflammatory diseases.

Citrus hallabong [(Citrus unshiu × C. sinensis) × C. reticulata)] exerts potent anti-inflammatory properties in murine splenocytes and TPA-induced murine ear oedema model.

CONTEXT: Hallabong [(Citrus unshiu × C. sinensis) X C. reticulata)] (Rutaceae) is a hybrid citrus cultivated in temperate regions of South Korea. Its fruit is well-known for pharmacological properties. OBJECTIVE: This study examined the anti-inflammatory effect of 80% ethanol extract of Hallabong (HE) on concanavalin A (Con A)-stimulated splenocytes and mouse oedema model induced by 12-O-tetradecanoylphorbal acetate (TPA). MATERIALS AND METHODS: Murine splenocytes treated with HE were stimulated with Con A (10 µg/mL, for 24 h) were evaluated for T-cell population and production of inflammatory cytokines IL-2, IL-4 and IFN-γ. Anti-inflammatory effect of topically applied HE (100 µg/20 µL) on TPA (4 µg/20 µL/ear)-induced ear oedema was investigated in mouse model. RESULTS: HE-treated Con A-stimulated murine splenocytes showed a marked decrease in CD44/CD62L+ memory T-cell population, an important marker for anti-inflammatory activity, and a significant inhibition in the production of IL-2 and IFN-γ. HE treatment had reduced the mouse skin oedema (47%) and myeloperoxidase (MPO) activity significantly (40%) in TPA-challenged tissues. More importantly, immunohistochemical localization revealed the suppressed (p < 0.05) expression of inducible nitric oxide (iNOS), cyclooxygenase-2 (COX2). HE decreased the infiltration of CD3+ T cells and F4/80+ macrophages to the site of inflammation and a topical application of HE significantly suppressed the expression of TNF-α (20.2%). DISCUSSION AND CONCLUSION: A topical application of HE can exert a potential anti-inflammatory effect and HE can be explored further as a putative alternative therapeutic agent for inflammatory oedema.