ABSTRACT
SCOPE: Chronic UVB exposure causes skin disorders and cancer through DNA strand breaks and oxidation of numerous functional groups of proteins and lipids in the skin. In this study, we investigated the effects of Thai banana (Musa AA group, "Khai," and Musa ABB group, "Namwa") on the prevention of UVB-induced skin damage when fed to male ICR mice. METHODS AND RESULTS: Mice were orally fed banana (Khai or Namwa) fruit pulps at dose of 1mg/g body weight/day for 12weeks. The shaved backs of the mice were irradiated with UVB for 12weeks. The intensity dose of UVB-exposure was increased from 54mJ/cm2/exposure at week 1 to 126mJ/cm2/exposure at week 12. A significant increase in skin thickness, lipid peroxidation, protein oxidation end products, and expression of MMP-1 was observed in UVB-irradiated mouse skin. A reduction in the accumulation of oxidation end products was found in the skin of UVB-irradiated mice receiving Khai. This occurred in conjunction with a reduction in MMP-1 expression, inhibition of epidermal thickening, and induction of γ-GCS expression. CONCLUSION: The dietary intake of Khai prevented skin damage from chronic UVB exposure by increased γ-GCS expression and reduced oxidation end products included carbonyls, malondialdehyde and 4-hydroxynonenal.
Subject(s)
Musa/metabolism , Skin/radiation effects , Ultraviolet Rays/adverse effects , Administration, Oral , Animals , Dose-Response Relationship, Radiation , Epidermis/pathology , Epidermis/radiation effects , Lipid Peroxidation , Male , Matrix Metalloproteinase 13/metabolism , Mice , Mice, Inbred ICR , Oxidation-Reduction , Skin/injuries , Skin/metabolism , ThailandABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Artocarpus altilis (Moreceae) has been widely used as a traditional folk medicine in Southeast Asia for the treatment of many diseases, including skin disorders, such as ulcers and dermatitis. AIM OF THE STUDY: The present study aimed to investigate the ability of an artocarpin-enriched extract to prevent ultraviolet radiation B-induced photodamage. MATERIALS AND METHODS: The content of artocarpin in the extract was determined by high performance liquid chromatography (HPLC). A DPPH assay was used to evaluate the free radical scavenging activity of the extract, which was compared with those of l-ascorbic acid and α-tocopherol. Cytotoxicity and proliferation of cells treated with the extract were determined using XTT and BrdU assays, respectively. Human skin fibroblasts and keratinocytes were pretreated with the extract for 24h and later irradiated with ultraviolet radiation B at 128 J/cm(2). The levels of TNF-α and IL-6 released from ultraviolet radiation B-irradiated keratinocytes and, MMP-1 and type-I procollagen produced by ultraviolet radiation B-irradiated fibroblasts were measured by ELISA and/or western blotting. The hairless skin of male mice (outbred ICR) was treated with the extract or l-ascorbic acid solution prior to exposure to ultraviolet radiation B irradiation. The dose of ultraviolet B irradiation was consecutively increased to 18, 36, 54, and 72 J/cm(2) at weeks 1-4, 4-7, 7-10, and 10-12, respectively. The epidermal thickness and collagen content in the skin of ultraviolet radiation B-irradiated mice were evaluated. RESULTS: The extract concentration of 50 µg/mL was not toxic and did not inhibit the proliferation of fibroblasts. The pretreatment of fibroblasts with 50 µg/mL extract prior to ultraviolet radiation B irradiation attenuated MMP-1 production but did not affect type-I procollagen production. The extract also decreased the ultraviolet radiation B-induced production of TNF-α and IL-6 in keratinocytes. Moreover, the topical administration of the extract suppressed epidermal thickening and collagen loss in chronically ultraviolet radiation B-exposed skin in mice. CONCLUSIONS: The experimental study revealed that A. altilis extract suppresses structural alterations in skin damaged by ultraviolet radiation B irradiation. This suppression was, at least partially, mediated by decrease in MMP-1 production in fibroblasts and TNF-α and IL-6 productions in keratinocytes.
Subject(s)
Artocarpus , Dermatologic Agents/pharmacology , Plant Extracts/pharmacology , Skin/drug effects , Skin/radiation effects , Ultraviolet Rays/adverse effects , Animals , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Cultured , Collagen/metabolism , Female , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/radiation effects , Humans , Interleukin-6/metabolism , Keratinocytes/drug effects , Keratinocytes/metabolism , Keratinocytes/radiation effects , Matrix Metalloproteinase 1/metabolism , Mice, Inbred ICR , Middle Aged , Skin/cytology , Skin/metabolism , Tumor Necrosis Factor-alpha/metabolism , WoodABSTRACT
Chitosan/silk fibroin (CS/SF) blend films were prepared and evaluated for feasibility of using the films as biomaterial for skin tissue engineering application. Fourier transform infrared spectroscopy and differential scanning calorimetry analysis indicated chemical interaction between chitosan and fibroin. Chitosan enhanced ß-sheet conformation of fibroin and resulted in shifting of thermal degradation of the films. Flexibility, swelling index, and enzyme degradation were also increased by the chitosan content of the blend films. Biocompatibility of the blend films was determined by cultivation with fibroblast cells. All films showed no cytotoxicity by XTT assay. Fibroblast cells spread on CS/SF films via dendritic extensions, and cell-cell interactions were noted. Cell proliferation on CS/SF films was also demonstrated, and their phenotype was examined by the expression of collagen type I gene. These results showed possibility of using the CS/SF films as a supporting material for further study on skin tissue engineering.
