chrysin and Dermatitis--Atopic

Gamma irradiation is a useful technology to change the physical and biological properties of natural molecules. In this study, we investigated whether gamma irradiation improve properties of chrysin as an anti-inflammatory candidates. Chrysin was converted into two compounds (CM1 and CM2) by gamma irradiation. We determined the therapeutic potential of these compounds in bone marrow-derived macrophages and 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions in Balb/c mice. The structural changes to chrysin led to the reduction of cytotoxicity without loss of anti-inflammatory properties in BMDMs. Purified CM2 inhibited lipopolysaccharide (LPS)-induced overexpression of nitric oxide, tumor necrosis factor-α, interleukin (IL)-6, and surface molecules without cytotoxicity in BMDMs, while CM1 revealed strong cytotoxicity. Furthermore, treatment with CM2 significantly alleviated AD-like skin symptoms and clinical signs in DNCB-induced AD mice model. The suppression of AD mediated by CM2 treatment was accompanied by decrease inflammatory T cell cytokines (IFN-γ, IL-5, IL-4, and IL-17). The chemical structure of CM2 and structural transformation mechanism were determined by nuclear magnetic resonance and mass spectrometry. Our study findings provide evidence that CM2 produced by gamma irradiation of chrysin can be an attractive therapeutic agent for AD.

Topics: Animals; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Disease Models, Animal; Female; Flavonoids; Gamma Rays; Irritants; Lymph Nodes; Mice, Inbred BALB C; Mice, Inbred C57BL; T-Lymphocytes

We previously reported the inhibitory effect of chrysin, a natural flavonoid plentifully contained in propolis, vegetables and fruits, on the mast cell-mediated allergic reaction. In this study, we evaluated the effect of chrysin on atopic dermatitis (AD) and defined underlying mechanisms of action. We used an AD model in BALB/c mice by the repeated local exposure of 2,4-dinitrochlorobenzene (DNCB) and house dust mite (Dermatophagoides farinae extract, DFE) to the ears. Repeated alternative treatment of DNCB/DFE caused AD-like skin lesions. Oral administration of chrysin diminished AD symptoms such as ear thickness and histopathological analysis, in addition to serum IgE and IgG2a levels. Chrysin decreased infiltration of mast cells, and reduced serum histamine level. Chrysin also suppressed AD by inhibiting the inflammatory responses of Th1, Th2, and Th17 cells in mouse lymph node and ear. Interestingly, chrysin significantly inhibited the production of cytokines, Th2 chemokines, CCL17 and CCL22 by the down-regulation of p38 MAPK, NF-κB, and STAT1 in tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated human keratinocytes (HaCaT). Chrysin also inhibited TNF-α/IFN-γ-stimulated IL-33 expression in HaCaT cells and mouse primary keratinocytes. Taken together, the results indicate that chrysin suppressed AD symptoms, suggesting that chrysin might be a candidate for the treatment of AD and skin allergic diseases.

Topics: Animals; Cytokines; Dermatitis, Atopic; Female; Flavonoids; Histamine; Humans; Immunoglobulin E; Keratinocytes; Mast Cells; Mice; Mice, Inbred BALB C; Th1 Cells; Th2 Cells; Tumor Necrosis Factor-alpha