The extract of buds of Chrysanthemum morifolium ramat alleviated UVB-induced skin photoaging by regulating MAPK and Nrf2/ARE pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Chrysanthemum morifolium Ramat. is a commonly used Chinese herb and food homologous plant with traditional effects such as anti-inflammatory, antifebrile, antibacterial and antiviral. AIM OF STUDY: Photoaging is one of the main causes of accelerated skin aging. Chrysanthemum morifolium Ramat. has reported to alleviate photodamage. In this study, we investigated the protective effect of the extract of buds of Chrysanthemum morifolium Ramat. (CE) on UVB-induced photoaging and further mechanism. MATERIALS AND METHODS: The extract of buds of chrysanthemum was analyzed by HPLC-Q-TOF-MS/MS. Antioxidant activity was assessed by DPPH and ABTS assay. Cell viability examined by cell counting kit-8 assay. The ROS level was detected by fluorescent probe DCFH-DA. Protein expression evaluated by Western blotting. The skin tissue investigated by immunohistochemistry. RESULTS: CE significantly reversed the decrease of cell viability that induced by UVB in HaCaT and HFF-1 cells. Further analysis showed that CE alleviated photoaging by inhibiting the expression of mitogen-activated protein kinase (MAPK) and activating the NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway to promote the expression of antioxidant enzymes. Moreover, CE effectively improved the reduced skin hydration, disordered collagen and thickening epidermis caused by UVB in mice. CONCLUSIONS: All results demonstrated that CE had therapeutic effect on UVB-induced photoaging and provided theoretical basis for its further developing as a natural functional product with anti-photoaging effect.

Adsorption of sulfur into an alkynyl-based covalent organic framework for mercury removal.

Highly efficient removal of Hg(ii) has been previously achieved through the adsorption by functionalized covalent organic frameworks (COFs). Among these COFs, thioether groups need to be deliberately introduced into the pores of COFs through either a bottom-up synthesis or post-synthesis strategy. Herein, we report a simple mercury removal strategy that used a stable alkynyl (-C[triple bond, length as m-dash]C-) based covalent organic framework (TP-EDDA COF) as an adsorbent for Hg(ii) removal. Sulfur vapor was first adsorbed by the TP-EDDA COF due to the van der Waals interaction between adsorbed sulfur and alkynyl groups. The Hg(ii) removal capability was then evaluated for the sulfur loaded TP-EDDA COF. Our results exhibited a good Hg(ii) removal performance for the sulfur loaded TP-EDDA COF. It was deduced that s⋯π interaction between sulfur atom and the alkynyl groups of the COF skeleton caused an increase in the electron density of sulfur and the electronegative sulfur atoms acted as a soft acid to accept soft-basic Hg(ii). This strategy provides a convenient platform for COFs to cope with environmental issues.