Skin aging appears to be principally related to a decrease in the levels of type I collagen, the primary component of the skin dermis. Asiaticoside, a saponin component isolated from Centella asiatica, has been shown to induce type I collagen synthesis in human dermal fibroblast cells. However, the mechanism underlying asiaticoside-induced type I collagen synthesis, especially at a molecular level, remains only partially understood. In this study, we have attempted to characterize the action mechanism of asiaticoside in type I collagen synthesis. Asiaticoside was determined to induce the phosphorylation of both Smad 2 and Smad 3. In addition, we detected the asiaticoside-induced binding of Smad 3 and Smad 4. In a consistent result, the nuclear translocation of the Smad 3 and Smad 4 complex was induced via treatment with asiaticoside, pointing to the involvement of asiaticoside in Smad signaling. In addition, SB431542, an inhibitor of the TGFbeta receptor I (TbetaRI) kinase, which is known to be an activator of the Smad pathway, was not found to inhibit both Smad 2 phosphorylation and Type 1 collagen synthesis induced by asiaticoside. Therefore, our results show that asiaticoside can induce type I collagen synthesis via the activation of the TbetaRI kinase-independent Smad pathway.

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protocols that tailor the absorption spectrum of the active material. [1][2][3][4][5][6] While such efforts have resulted in a library of active materials, they have also presented challenges for commercial viability due to the different processes and costs associated with employing distinct active materials to display different colors. Their use has also resulted in varied performances among devices of different colors, adding to the difficulty for practical implementation. Furthermore, challenges in organic synthesis have limited the achievable types of color and their spectral purity. In this work, we introduce a strategy that enables a single active material that absorbs uniformly across the visible range to display different colors with high spectral purity and consistent device performances through the implementation of a color filtering (CF) electrode. The electrode consists of a Ag-TiO x -Ag Fabry-Perot (FP) resonant cavity, where the thickness of the TiO x layer determines the spectral position of the transmission peak and the inner Ag layer functions as an electrical contact. The electrode also functions as a mirror for all wavelengths of light except that within the resonant band (i.e., the spectral transparency window) of the CF. Therefore, light that has not been selectively transmitted may reflect back into the active material, contributing to additional charge generation. This implies that the short-circuit current density, which is largely a function of the optical absorption, must be higher for a CF-integrated OPV compared to a transparent OPV, under the condition that the two devices show similar peak transmission efficiencies.The use of photonic structures as optical filters in OPVs or inorganic solar cells has been previously reported in the form of distributed Bragg reflectors, [7][8][9] photonic arrays, [10][11][12] and plasmonic resonators. [13][14][15] While such filters enable various colors to be transmitted or reflected through tuning of the characteristic dimension of the filter components, in many cases they suffer from increased fabrication costs and duration because of the structural complexity. Moreover, photonic structures employing low-loss dielectrics exhibit poor electrical conductivity, precluding their use as an electrode. Finally, the structural anisotropy intrinsic to 1D or 3D photonic structures can result in asymmetric responses for light incident from above and below the device. Such behavior can complicate design schemes for creating bidirectional colored windows.Colorful, semitransparent organic photovoltaic cells (OPVs) are increasing in demand due to their applicability in aesthetically fashioned powergenerating windows. The traditional method of generating different colors in OPVs has been through employing different active materials exhibiting distinct absorption spectra. This can complicate fabrication processes for production and cause deviations in device performance among differently colored OPVs. Herein, semitransparent and colorful OPVs with a single broadban...

Semitransparent colorful organic solar cells (OSC) provide exciting opportunities for harnessing sunlight as colored windows. Previously, color filter (CF) electrodes on (OSC) were demonstrated via vacuum-deposition techniques, resulting in deposition-induced damage. Thus, we present CF integrated organic photovoltaics (CF-OPVs) using solution-processed TiO2–AcAc as the dielectric component. The noninvasive processing substantially expands the range of usable active materials, allowing the device to display pure and vibrant colors that are independent of the inherent color of the active material and show superior optical and photovoltaic characteristics. These results provide practical pathways to realizing colored semitransparent solar cells.

1 Tumor necrosis factor (TNF)-a is known to induce the expression of CCL11 and CCR3 via the activation of NF-kB. CCL11 (eotaxin), the C-C chemokine, is a potent chemoattractant for eosinophils and Th2 lymphocytes, and CCR3 is the receptor for CCL11. 2 In order to determine the effects of rosmarinic acid on the TNF-a-induced upregulation of CCL11 and CCR3 in human dermal fibroblasts, we performed an enzyme-linked immunosorbent assay for CCL11 and a Western blot assay for CCR3. The TNF-a-induced expression of CCL11 and CCR3 genes was attenuated by rosmarinic acid. 3 In our NF-kB luciferase reporter system, TNF-a-induced NF-kB activation was observed to be reduced by rosmarinic acid. In accordance with this result, rosmarinic acid also inhibited TNF-ainduced phosphorylation and degradation of IkB-a, as well as nuclear translocation of NF-kB heterodimer induced by TNF-a. This suggests that rosmarinic acid downregulates the expression of CCL11 and CCR3 via the inhibition of NF-kB activation signaling. 4 Using the NF-kB luciferase reporter system, Western blot analysis, and IKK-b activity assay, we determined that rosmarinic acid inhibits IKK-b activity in NF-kB signaling, which upregulates the expression of CCL11 and CCR3. Additionally, TNF-a-induced secretion of soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 molecules was found to be attenuated by rosmarinic acid. 5 Our results show that rosmarinic acid inhibits the expression of CCL11 and CCR3 by suppressing the IKK-b activity in NF-kB activation signaling. Further, these results suggest that rosmarinic acid might inhibit the expression of NF-kB promoter-related genes.