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Green tea polyphenols (GTPs) are regarded as anticancer substance and have been revealed to play significant roles in the development of malignant melanoma. However, the mechanisms by which GTPs perform anti-carcinogenic activity are not well elucidated. Cellular function assays revealed that GTPs inhibited melanoma cell proliferation, migration, invasion, EMT, and promoted apoptosis in vitro. Circ_MITF expression was elevated in melanoma tissues and cells, but was decreased by GTPs in cells. Functional experiments indicated circ_MITF overexpression reversed the anticancer effects of GTPs on melanoma cells. Then the underlying mechanism analysis suggested that circ_MITF served as a sponge for miR-30e-3p to up-regulate the level of HDAC2. MiR-30e-3p re-expression attenuated the regulatory effects of circ_MITF on GTPs-treated melanoma cells. Silencing of miR-30e-3p promoted the malignant phenotypes in GTPs-treated melanoma cells, which were reversed by HDAC2 knockdown. Pre-clinically, administration of GTPs suppressed the expression of downstream target genes, and repressed tumorigenesis of xenografts in nude mice. In all, GTPs suppressed melanoma progression by regulating circ_MITF/miR-30e-3p/HDAC2 axis, providing a potential therapeutic strategy for human malignant melanoma intervention. This article is protected by copyright. All rights reserved.

Background and purpose Cocamide monoethanolamide (CMEA) is commonly used as a surfactant-foam booster in cosmetic formulations. Upon contact with the eye or other sensitive skin areas, CMEA elicits stinging and lasting irritation. We hypothesized a specific molecular interaction with TRPV1 channels by which CMEA caused eye irritation. Experimental approach Eye irritancy was evaluated using eye-wiping tests in rabbits and mice. Intracellular Ca2+ concentrations and action potentials were measured using Ca2+ imaging and current clamp respectively. Voltage clamp, site-direct mutagenesis and molecular modelling were used to identify binding pockets for CMEA on TRPV1 channels. Key results CMEA-induced eye irritation is ameliorated by selective ablation of TRPV1 channels.Rodents exhibit much stronger responses to CMEA than rabbits. In trigeminal ganglion neurons, CMEA induced Ca2+ influx and neuronal excitability, effects mitigated by a TRPV1 channel inhibition and absent in TRPV1 knockout neurons. In HEK-293 cells expressing TRPV1 channels, CMEA increased whole-cell currents by increasing channel open probability (EC50 = 10.2 μM), without affecting TRPV2, TRPV3, TRPV4, and TRPA1 channel activities. Lauric acid monoethanolamide (LAMEA), the most abundant constituent of CMEA, was the most efficacious and potent TRPV1 channel activator, binding to the capsaicin-binding pocket of the channel. The T550I mutants of rabbit and human TRPV1 channels exhibit much lower sensitivity to LAMEA. Conclusions and implication CMEA directly activates TRPV1 channels to produce eye irritation. Rabbits, the standard animal used for eye irritancy tests are poor models for evaluating human eye irritants structurally related to CMEA. Our study identifies potential alternatives to CMEA as non-irritating surfactants.

Hyperoside has been reported to possess anti‐inflammatory properties. Here, we confirmed that hyperoside exhibits potential therapeutic properties against periodontitis via promotion of proliferation and osteogenic differentiation of rat bone mesenchymal stem cells through activation of the NF‐κB signaling pathway. Therefore, our study provides evidence that hyperoside may have potential as a novel therapeutic option for periodontitis treatment., Hyperoside, as an active compound, widely exists in a large number of Chinese herbal medicines and has been reported to possess anti‐inflammatory and diuretic properties. However, the effects and underlying mechanisms of hyperoside on periodontitis have not been previously reported. In this study, we found that hyperoside ameliorates symptoms of periodontitis in a rat model, with improvements in alveolar bone resorption, relief of inflammatory infiltration, increase in orderly arrangement of collagen fibers and increase of osteogenic differentiation. In addition, hyperoside promoted proliferation, up‐regulated EdU‐positive cells, decreased cell‐cycle distribution and increased the protein expression of Ki67 and PCNA in rat bone mesenchymal stem cells (rBMSCs), as revealed by Cell Counting Kit‐8, EdU, flow cytometry and western blot analysis. Moreover, hyperoside significantly promoted osteogenic differentiation, as shown by quantitative RT‐PCR, western blot and alizarin red staining assays. Furthermore, hyperoside activated the nuclear factor‐κB (NF‐κB) signaling pathway in rBMSCs, similar to the results observed in vivo. Finally, BMS345541, an inhibitor of the NF‐κB signaling pathway, could reverse the effects of hyperoside on the biological functions in rBMSCs. In conclusion, our results suggest that hyperoside has potential therapeutic properties against periodontitis via promotion of proliferation and osteogenic differentiation of rBMSCs via activation of the NF‐κB signaling pathway.

The conjugation of hydrophilic low-fouling polymers to therapeutic molecules and particles is an effective approach to improving their aqueous stability and solubility, and extending their pharmacokinetics. Recent concerns over the immunogenicity of poly(ethylene glycol) has highlighted the importance of identifying alternative low fouling polymers. Herein, we report a new class of synthetic water-soluble homo-fluoropolymers with a sulfoxide side-chain structure. The incorporation of fluorine enables direct imaging of the homopolymer by 19 F MRI, negating the need for additional synthetic steps to attach an imaging moiety. These self-reporting fluoropolymers show outstanding imaging sensitivity and as such represent a new class of low-fouling polymer for bioconjugation and in vivo tracking.

Two‐dimensional material (2D) that possesses atomic thin geometry and remarkable properties is a star material for the fundamental researches and advanced applications. Defects in 2D materials are critical and fundamental to understand the chemical, physical, and optical properties. Photoluminescence arises in 2D materials owing to various physical phenomena including activator/dopant‐induced luminescence and defect‐related emissions, and so forth. With the advanced transmission electron microscopy (TEM) technologies, such as aberration correction and low voltage technologies, the morphology, chemical compositions and electronic structures of defects in 2D material could be directly characterized at the atomic scale. In this review, we introduce the applications of state‐of‐the‐art TEM technologies on the studies of the role of atomic defects in the photoluminescence characteristics in 2D material. The challenges in spatial and time resolution are also discussed. It is proved that TEM is a powerful tool to pinpoint the relationship between the defects and the photoluminescence characteristics.