Ultraviolet B-induced Photoaging Research Articles

Ethanol extract of Dalbergia odorifera protects skin keratinocytes against ultraviolet B-induced photoaging by suppressing production of reactive oxygen species.

Dalbergia odorifera T. Chen (Leguminosae), an indigenous medicinal herb, has been widely used in northern and eastern Asia to treat diverse diseases. Here, we investigated the anti-senescent effects of ethanolic extracts of Dalbergia odorifera (EEDO) in ultraviolet (UV) B-irradiated skin cells. EEDO significantly inhibited UVB-induced senescence of human keratinocytes in a concentration-dependent manner, concomitant with inhibition of reactive oxygen species (ROS) generation. UVB-induced increases in the levels of p53 and p21, biomarkers of cellular senescence, were almost completely abolished in the presence of EEDO. Sativanone, a major constituent of EEDO, also attenuated UVB-induced senescence and ROS generation in keratinocytes, indicating that sativanone is an indexing (marker) molecule for the anti-senescence properties of EEDO. Finally, treatment of EEDO to mice exposed to UVB significantly reduced ROS levels and the number of senescent cells in the skin. Thus, EEDO confers resistance to UVB-induced cellular senescence by inhibiting ROS generation in skin cells.

Dietary supplementation with a fermented barley and soybean mixture attenuates UVB-induced skin aging and dehydration in hairless mouse skin

This study evaluated the protective effects of dietary supplementation with a fermented barley and soybean mixture (BS) on ultraviolet (UV) B-induced photoaging in hairless mice. Skin aging-related parameters and protein levels related to skin wrinkles and moisturization in mice were analyzed. The BS reduced wrinkle formation, skin thickening, transepidermal water loss, and matrix metalloproteinases-1 expression in skin. Skin hydration and pH were increased in the BS group. BS attenuated filaggrin expression as well as free amino acid and glycerol production. BS increased superoxide dismutase activity as well as increased expression of nuclear factor (erythroid-derived 2)-like 2, procollagen type-I, and decreased erythema. These results suggest that BS protects against photoaging induced by UVB in vivo, indicating the potential of such mixtures as anti-photoaging dietary supplementation.

Oral administration of Lactobacillus plantarum HY7714 protects hairless mouse against ultraviolet B-induced photoaging.

Ultraviolet (UV) irradiation alters multiple molecular pathways in the skin, thereby inducing skin damage, including photoaging. In recent years, probiotics have gained interest due to their beneficial effects on skin health, such as inhibiting atopic dermatitis and improving skin immunity or inflammation. However, little is known about the effects of probiotics on UVBinduced photoaging. In this study, we evaluated the effect of Lactobacillus plantarum HY7714 against UVB-induced photoaging in human dermal fibroblasts and hairless mice. The results showed that L. plantarum HY7714 treatment effectively rescued UVB-reduced procollagen expression through the inhibition of UVB-induced matrix metalloproteinase (MMP)-1 expression in human dermal fibroblasts. Data from a western blot showed that L. plantarum HY7714 inhibited the phosphorylation of Jun N-terminal kinase, thereby suppressing the UVB-induced phosphorylation and expression of c-Jun. Oral administration of L. plantarum HY7714 clearly inhibited the number, depth, and area of wrinkles in hairless mouse skin. Histological data showed that L. plantarum HY7714 significantly inhibited UVB-induced epidermal thickness in mice. Western blot and zymography data also revealed that L. plantarum HY7714 effectively inhibited MMP-13 expression as well as MMP-2 and -9 activities in dermal tissue. Collectively, these results provide further insight regarding the skin biological actions of L. plantarum HY7714, a potential skin anti-photoaging agent.

EGb-761 prevents ultraviolet B-induced photoaging via inactivation of mitogen-activated protein kinases and proinflammatory cytokine expression

BackgroundEGb-761 is an antioxidant and anticarcinogen; however, its role as a photoprotector remains unknown. ObjectiveTo determine whether EGb-761 photoprotects human dermal fibroblasts and BALB/c mice skin against ultraviolet B (UVB) light irradiation. MethodsTo simulate chronic photodamage, shaved BALB/c mice were exposed to UVB irradiation (90mJ/cm2) thrice weekly for 3 months. EGb-761 (2mg/cm2) was topically applied 1h before irradiation to evaluate its effect. The mechanisms by which EGb-761 protects the skin from photodamage were evaluated by immunohistochemical analysis, enzyme-linked immunosorbent assay (ELISA), and Western blotting. ResultsIn BALB/c mice, the signs of photoaging or photodamage, such as coarse wrinkle formation, epidermal hyperplasia, and elastic fiber degeneration, markedly reduced with the topical application of EGb-761. Western blot and ELISA revealed that the activation of MMP-1 in cultured fibroblasts markedly diminished after pretreatment with EGb-761. In addition, EGb-761 inhibited UVB-induced overexpression by the fibroblasts of the proinflammatory cytokines, such as interleukin (IL)-1α, IL-1β, IL-6, and tumor necrosis factor-α. The phosphorylation of the mitogen-activated protein kinase (MAPK) signal transduction pathway components, including extracellular signal-regulated kinase, C-Jun N-terminal kinase, and p38, which are induced by UV irradiation, was significantly inhibited in vivo and in vitro. EGb-761 also diminished the generation of UVB-induced reactive oxygen species (ROS). ConclusionsEGb-761 photoprotects mice and cultured fibroblasts, inhibits the UVB-induced phosphorylation of MAPK pathway components, and reduces the expression of the proinflammatory cytokines by suppressing ROS generation. Thus, topically applied EGb-761 may be a promising photoprotective agent.

Sauchinone, a Lignan from <i>Saururus chinensis</i>, Protects Human Skin Keratinocytes against Ultraviolet B-Induced Photoaging by Regulating the Oxidative Defense System

Ultraviolet (UV) radiation from sunlight induces matrix metalloproteinase (MMP) expression, which are responsible for collagenous extracellular matrix proteins breakdown in skin, causing photoaging. Sauchinone is reported to have various bioactivity such as antioxidative, hepatoprotective, and anti-inflammatory effects. In the present study, we investigated the protective effect of sauchinone against UVB (50 mJ/cm(2))-induced photoaging in HaCaT human epidermal keratinocytes. Sauchinone, at 5-40 µM, significantly protected keratinocytes against UVB-induced damage as assessed by cell viability and toxicity assay. Additionally, sauchinone, at 20-40 µM, prevented the upregulation of MMP-1 proteins and reduction of type 1 collagen induced by UVB. Other assays revealed that, in keratinocytes, sauchinone decreased reactive oxygen species (ROS) production and increased glutathione levels and heme oxygenase-1. Sauchinone also inhibited UVB-induced phosphorylation of mitogen-activated protein kinase (MAPK) signaling pathways. These results demonstrated that sauchinone protects skin keratinocytes through inhibition of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 MAPK signaling via upregulation of oxidative defense enzymes.