Methanol Extract of Bitter Melon Alleviates UVB-Induced MMPs Expression via MAP Kinase and AP-1 Signaling in Human Dermal Fibroblasts in vitro.

Ultraviolet (UV) irradiation leads to photo-damage of the skin, which in turn induces expression of matrix metalloproteinases (MMPs) and reduces type I procollagen. Bitter melon (Momordica charantia L.) has been widely used as a traditional medicine. In this study, we tested the photo-protective effects of methanol extracts of bitter melon pulp (BM) and the mechanism of these effects in normal human dermal fibroblasts (NHDFs). The effects of BM were investigated by measuring the levels of MMP-1, -3 and -9, and type I procollagen following UVB irradiation. We found that BM alleviates UVB-induced MMP-1, -3 and -9 expression at 100 µg/mL (down to 52.0%, 73.5%, and 55.6%, respectively). However, cells treated with 100 µg/mL BM had weakly stimulated type I procollagen expression (up to 130.0%). Moreover, treatment with BM significantly reduced UVB-induced extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK), and p38 phosphorylation, which resulted in decreasing UVB-induced phosphorylation of c-Fos and c-Jun. Therefore, our results suggest that BM is a potential agent for regulating skin photoaging. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of Galla chinensis extracts on UVB-irradiated MMP-1 production in hairless mice.

Galla chinensis (GAC) is a natural traditional Chinese medicine that has been widely used in folk medicine. Although GAC compounds (mainly gallic acid and methyl gallate) possess strong antiviral, antibacterial, anticancer, and antioxidant activities, there is no report regarding topical or oral administration of GAC compounds on UVB irradiation-induced photoaging in hairless mice (SKH: HR-1). In the present study, we examined cell viability, intracellular reactive oxygen species (ROS), matrix metalloproteinase-1 (MMP-1), and interleukin-6 (IL-6) in skin fibroblasts and keratinocytes induced by UVB in vitro. We also studied skin damage by measuring skin thickness, elasticity, wrinkling and levels of protein MMP-1, elastin, procollagen type I, and transforming growth factor-ß1 (TGF-ß1) in hairless mouse skin chronically irradiated by UVB in vivo. GAC treatment significantly prevented skin photoaging by reducing the levels of ROS, MMP-1, and IL-6 and promoting production of elastin, procollagen type I, and TGF-ß1. According to the results of H&E staining and Masson's trichrome staining, GAC reduced skin thickness and wrinkle formation while it increased skin elasticity. The effects of GAC on UVB-induced skin photoaging may be due to suppressed MMP-1 expression. These findings could be referenced for the development of new agents that target UVB-induced photoaging.

Vigna angularis water extracts protect against ultraviolet b-exposed skin aging in vitro and in vivo.

Exposure to ultraviolet (UV) radiation induces various pathological changes, such as thickened skin and wrinkle formation. In particular, UVB irradiation increases matrix metalloproteinase (MMP)-1 production and collagen degradation, leading to premature aging, termed photoaging. The azuki bean (Vigna angularis; VA) has been widely used as a food product as well as a traditional medicine. However, its activity needs additional study to confirm its functional application in foods and cosmetics for protecting skin. In this study, hot-water extract from VA (VAE) and its active component, rutin, were investigated to determine their antiphotoaging effects. VAE was found to have antioxidant activity. In UVB-exposed normal human dermal fibroblasts cells with VAE and rutin treatments, MMP-1 production was significantly suppressed (90% and 47%, respectively). The effects of both topical and oral administration of VAE were tested in UVB-irradiated hairless mice. VAE suppressed wrinkle formation and skin thickness by promoting elastin, procollagen type I, and TGF-ß1 expression (118%, 156%, and 136%, respectively) and by diminishing MMP-1 production. These results suggest that VAE may be effective for preventing skin photoaging accelerated by UVB radiation.

Gallic acid regulates skin photoaging in UVB-exposed fibroblast and hairless mice.

Ultraviolet (UV) radiation is the primary factor in skin photoaging, which is characterized by wrinkle formation, dryness, and thickening. The mechanisms underlying skin photoaging are closely associated with degradation of collagen via upregulation of matrix metalloproteinase (MMP) activity, which is induced by reactive oxygen species (ROS) production. Gallic acid (GA), a phenolic compound, possesses a variety of biological activities including antioxidant and antiinflammatory activities. We investigated the protective effects of GA against photoaging caused by UVB irradiation using normal human dermal fibroblasts (NHDFs) in vitro and hairless mice in vivo. The production levels of ROS, interlukin-6, and MMP-1 were significantly suppressed, and type I procollagen expression was stimulated in UVB-irradiated and GA-treated NHDFs. GA treatment inhibited the activity of transcription factor activation protein 1. The effects of GA following topical application and dietary administration were examined by measuring wrinkle formation, histological modification, protein expression, and physiological changes such as stratum corneum hydration, transepidermal water loss, and erythema index. We found that GA decreased dryness, skin thickness, and wrinkle formation via negative modulation of MMP-1 secretion and positive regulation of elastin, type I procollagen, and transforming growth factor-ß1. Our data indicate that GA is a potential candidate for the prevention of UVB-induced premature skin aging.