Anti-inflammatory Constituents from Branches of Corylus hallaisanensis Nakai.

Development of bioactive ingredients from natural sources has long been the research project of our laboratory. In this study, the extract from Corylus hallaisanensis Nakai branches was investigated and their anti-inflammatory constituents were identified. The prepared ethanol extract was successively partitioned into n-hexane, ethyl acetate, n-butanol and aqueous layers. Upon anti-inflammatory screenings, ethyl acetate fraction exhibited good nitric oxide production inhibitory activity in lipopolysaccharide-induced RAW 264.7 cells. Further phytochemical studies for the ethyl acetate fractions led to isolation of four constituents such as β-sitosterol (1), 3,3’,4’-tri-O-methylellagic acid (2), carpinontriol A (3) and carpinontriol B (4). All of the compounds were isolated for the first time from this plant. The isolates 2, 3 and 4 showed considerable inhibition on the production of nitric oxide in the RAW 264.7 cell without causing cell toxicities. And compounds 3 and 4 reduced the production of interleukin-6, an inflammatory cytokine, in dose-dependent manner in RAW 264.7 cells. Based on these results, C. hallaisanensis extracts could be potentially applicable as anti-inflammatory agents in pharmaceutical or cosmetic industries.

Chemical compositions and anti-inflammatory activities of essential oils from Aster spathulifolius and Vitex rotundifolia maxim.

The essential oils were prepared from Aster spathulifolius (ASE) and Vitex rotundifolia (VRE) by hydrodistillation and their chemical compositions were investigated by GC–MS. Analysis of ASE provided 15 components and eight of which were identified sesquiterpene compounds. The major components in ASE included germacrene D (35.1 %), trans-caryophyllene (15.9 %) and trans-phytol (14.9 %). On the other hand, VRE provided manoyl oxide (14.3%), α-terpineol (13.1 %) and α-pinene (10.0 %) as major ingredients. To assess the anti-inflammatory effects of the essential oils, the production of nitric oxide (NO) and tumor necrosis factor (TNF)-α were monitored using lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. In this test, ASE and VRE were appeared to suppress both NO and TNF-α synthesis in dose-dependent manner. The results indicate that VRE and ASE could be useful in cosmetic applications as natural products possessing antiinflammatory efficacy

Melanogenesis Inhibitory Activity in the Extracts of Oreocnide fruticosa (Gaudich.) Hand-Mazz. Branches.

Development of anti-melanogenic agents from natural sources has long been the research project of our laboratory. In this study, ethyl acetate extracts of Oreocnide fruticosa (Gaudich.) Hand.-Mazz. branches (OBE) were examined for their melanin synthesis inhibitory activities using B16 melanoma cells. Our results indicated that OBE down-regulates melanin production in a dose-dependent pattern. To clarify the target of OBE action in melanogenesis, we performed Western blotting for the key melanogenic enzymes; tyrosinase, tyrosinase related protein-1 (TRP-1) and TRP-2. The results showed that OBE efficiently inhibited tyrosinase, TRP-1 and TRP-2 in a dose-dependent manner. Therefore, OBE is a good candidate for the further study including identification of the effective chemical constituents as well as their working mechanism for the application of whitening agent in the human skin.

Inhibitory Effect of Ulva fasciata and Desmarestia viridis on the Production of Nitric Oxide, Prostaglandin E2, and Pro-inflammatory Cytokines in RAW 264.7 Cells.

Nitric oxide (NO) and prostaglandin (PG)E2, known inflammatory mediators, are critically involved in the pathogenesis of a large number of human inflammatory diseases. Therefore, a search of inducible nitric oxide synthases (iNOS) and cyclooxygenase 2 (COX-2) selective inhibitors is a useful strategy to find functional substances to alleviate inflammatory disease. In our search for anti-inflammatory ingredients, we found that extracts of Ulva fasciata (UFE) and Desmarestia viridis (DVE) inhibit the generation of NO and PGE2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. U. fasciata and D. viridis were extracted with 80% ethanol and then partitioned successively with ethyl acetate. The ethyl acetate fractions are effective dose-dependent inhibitors of LPS-induced NO and PGE2 synthesis in RAW 264.7 cells. To test the inhibitory effects of UFE and DVE on pro-inflammatory cytokines, we performed ELISA assays for tumor necrosis factor (TNF)-α, IL (interleukin)-1β, and IL(interleukin)-6 in LPS-stimulated RAW 264.7 macrophage cells. In these assays, the UFE and DVE showed a dose-dependent decrease in the production of TNF-α, IL-1β, and IL-6. As a preliminary study of the anti-inflammatory mechanism, we determined, using the Western blot analysis, whether or not UFE and DVE inhibit the degradation of I-kappa-B-alpha (IκB-α). Our results indicate that UFE and DVE indeed prevent the degradation of IκB-α, in a dose-dependent manner. Based on these results, we suggest that extracts of U. fasciata and D. viridis be considered candidates for anti-inflammatory agents for human use.

Down-regulation of tyrosinase, TRP-1, TRP-2 and MITF expressions by citrus press-cakes in murine B16 F10 melanoma

Objective: To investigate the suitability of citrus-press cakes, by-products of the juice industry as a source for the whitening agents for cosmetic industry. Methods:Ethylacetate extracts of citrus-press cakes (CCE) were examined for their anti-melanogenic potentials in terms of the inhibition of melanin production and mechanisim of melanogenesis by using Western Blot analysis with tyrosinese, tyrosinase-related protein-1 (TRP-1), TRP2, and microphthalmia-associated transcription factor (MITF) proteins. To apply the topical agents, citrus-press cakes was investigated the safety in human skin cell line. Finally flavonoid analysis of CCE was also determined by HPLC analysis. Results: Results indicated that CCE were shown to down-regulate melanin content in a dose-dependent pattern. The CCE inhibited tyrosinase, TRP-2, and MITF expressions in a dose-dependent manner. To test the applicability of CCE to human skin, we used MTT assay to assess the cytotoxic effects of CCE on human keratinocyte HaCaT cells. The CCE exhibited low cytotoxicity at 50 μg/mL. Characterization of the citrus-press cakes for flavonoid contents using HPLC showed varied quantity of rutin, narirutin, and hesperidin. Conclusions:Considering the anti-melanogenic activity and human safety, CCE is considered as a potential anti-melanogenic agent and may be effective for topical application for treating hyperpigmentation disorders.