Combination Effect of Titrated Extract of Centella asiatica and Astaxanthin in a Mouse Model of Phthalic Anhydride-Induced Atopic Dermatitis

PURPOSE: In our previous study, we demonstrated that both titrated extract of Centella asiatica (TECA) and astaxanthin (AST) have anti-inflammatory effects in a 5% phthalic anhydride (PA) mouse model of atopic dermatitis (AD). The increasing prevalence of AD demands new therapeutic approaches for treating the disease. We investigated the therapeutic efficacy of the ointment form of TECA, AST and a TECA + AST combination in a mouse model of AD to see whether a combination of the reduced doses of 2 compounds could have a synergistic effect. METHODS: An AD-like lesion was induced by the topical application of 5% PA to the dorsal ear and back skin of an Hos:HR-1 mouse. After AD induction, TECA (0.5%), AST (0.5%) and the TECA (0.25%) + AST (0.25%) combination ointment (20 μg/cm2) were spread on the dorsum of the ear or back skin 3 times a week for 4 weeks. We evaluated dermatitis severity, histopathological changes and changes in protein expression by Western blotting for inducible nitric oxide synthase (iNOS), cyclocxygenase (COX)-2, and nuclear factor (NF)-κB activity. We also measured the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and immunoglobulin E (IgE) in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA). RESULTS: PA-induced skin morphological changes and ear thickness were significantly reduced by TECA, AST and TECA + AST treatments, but these inhibiting effects were more pronounced in the TECA + AST treatment. TECA, AST and the TECA+AST reatments inhibited the expression of iNOS and COX-2; NF-κB activity; and the release of TNF-α, IL-6 and IgE. However, the TECA+AST treatment showed additive or synergistic effects on AD. CONCLUSIONS: Our results demonstrate that the combination of TECA and AST could be a promising therapeutic agent for AD by inhibiting NF-κB signaling.

Anti-inflammatory effect of Centella asiatica phytosome in a mouse model of phthalic anhydride-induced atopic dermatitis.

BACKGROUND: Centella asiatica phytosome (CA phytosome) has potent antioxidant and anti-inflammatory properties. However, its anti-dermatitic effect has not yet been reported. PURPOSE: We investigated the effects of CA phytosome on inflammatory reponses by macrophages in an atopic dermatitis (AD) mouse model. STUDY DESIGN: The effects of CA phytosome on atopic dermatitis were examined by using phthalic anhydride (PA)-induced AD mouse model and RAW 264.7 murine macrophages. METHODS: An AD-like lesion was induced by a topical application of 5% phthalic anhydride (PA) to the dorsal skin or ear of HR-1 mice. After AD induction, 100 µl (20 µl/cm2) of 0.2% and 0.4% CA phytosome was spread on the dorsal skin and ear of the mice three times a week for four weeks. We evaluated histopathological changes and changes in protein expression by Western blotting for iNOS and COX-2; NF-κB activity was determined by EMSA. We also measured TNF-α, IL-1ß, and IgE concentration in the blood of AD mice by ELISA. RESULTS: Histological analysis showed that CA phytosome inhibited infiltration of inflammatory cells. CA phytosome treatment inhibited the expression of iNOS and COX-2, activity of NF-κB, and release of TNF-α, IL-1ß, and IgE. In addition, CA phytosome (5, 10, and 20 µg/ml) potently inhibited LPS (1 µg/ml)-induced NO production as well as iNOS and COX-2 expression in RAW 264.7 macrophage. Furthermore, CA phytosome inhibited LPS-induced DNA binding activities of NF-κB, and this was associated with the discontinuation of IκBα degradation and subsequent decreases in the translocation of p65 and p50 into the nucleus. CONCLUSION: From our data, CA phytosome application, which operates via NF-κB signaling inhibition, seems to be a promising AD treatment. Herein, we investigated the effects of Centella asiatica phytosome (CA phytosome) on inflammatory responses by macrophages in an atopic dermatitis (AD) mouse model. An AD-like lesion was induced by the topical application of 5% phthalic anhydride (PA) to the dorsal skin or ear of HR-1 mice. After AD induction, 100 µl (20 µl/cm2) of 0.2% and 0.4% CA phytosome was spread on the dorsal skin and ear of the mice three times a week for four weeks. We evaluated dermatitis severity, histopathological changes, and changes in protein expression by Western blotting for iNOS and COX-2; NF-κB activity was determined by gel electromobility shift assay (EMSA). We also measured TNF-α, IL-1ß, and IgE concentration in the blood of AD mice by enzyme-linked immunosorbent assay (ELISA). CA phytosome attenuated the development of PA-induced AD. Histological analysis showed that CA phytosome inhibited hyperkeratosis, proliferation of mast cells, and infiltration of inflammatory cells. Furthermore, CA phytosome treatment inhibited the expression of iNOS and COX-2, activity of NF-κB, and release of TNF-α, IL-1ß, and IgE. In addition, CA phytosome (5, 10, and 20 µg/ml) potently inhibited lipopolysaccharide (LPS) (1 µg/ml)-induced NO production as well as iNOS and COX-2 expression in RAW 264.7 macrophage cells. Furthermore, CA phytosome inhibited LPS-induced DNA binding activities of NF-κB, and this was associated with the discontinuation of IκBα degradation and subsequent decreases in the translocation of p65 and p50 into the nucleus. From our data, CA phytosome application, which operates via NF-κB signaling inhibition, seems to be a promising AD treatment.

Imidazole Antifungal Drugs Inhibit the Cell Proliferation and Invasion of Human Breast Cancer Cells

Breast cancer is currently the most prevalent cancer in women, and its incidence increases every year. Azole antifungal drugs were recently found to have antitumor efficacy in several cancer types. They contain an imidazole (clotrimazole and ketoconazole) or a triazole (fluconazole and itraconazole) ring. Using human breast adenocarcinoma cells (MCF-7 and MDA-MB-231), we evaluated the effects of azole drugs on cell proliferation, apoptosis, cell cycle, migration, and invasion, and investigated the underlying mechanisms. Clotrimazole and ketoconazole inhibited the proliferation of both cell lines while fluconazole and itraconazole did not. In addition, clotrimazole and ketoconazole inhibited the motility of MDA-MB-231 cells and induced G₁-phase arrest in MCF-7 and MDA-MB-231 cells, as determined by cell cycle analysis and immunoblot data. Moreover, Transwell invasion and gelatin zymography assays revealed that clotrimazole and ketoconazole suppressed invasiveness through the inhibition of matrix metalloproteinase 9 in MDA-MB-231 cells, although no significant changes in invasiveness were observed in MCF-7 cells. There were no significant changes in any of the observed parameters with fluconazole or itraconazole treatment in either breast cancer cell line. Taken together, imidazole antifungal drugs showed strong antitumor activity in breast cancer cells through induction of apoptosis and G₁ arrest in both MCF-7 and MDA-MB-231 cells and suppression of invasiveness via matrix metalloproteinase 9 inhibition in MDA-MB-231 cells. Imidazole drugs have well-established pharmacokinetic profiles and known toxicity, which can make these generic drugs strong candidates for repositioning as antitumor therapies.