1.Hyperoside protects human primary melanocytes against H2O2-induced oxidative damage.
Yang B1, Yang Q2, Yang X1, Yan HB1, Lu QP3. Mol Med Rep. 2016 Apr 12. doi: 10.3892/mmr.2016.5107. [Epub ahead of print]
Cuscutae semen has been shown to have beneficial effects in the treatment of vitiligo, recorded in the Chinese Pharmacopoeia, whereas the effects of its constituent compounds remains to be elucidated. Using a tetrazolium bromide assay, the present study found that hyperoside (0.5‑200 µg/ml) significantly increased the viability of human melanocytes in a time‑ and dose‑dependent manner. The present study used a cell model of hydrogen peroxide (H2O2)‑induced oxidative damage to examine the effect of hyperoside on human primary melanocytes. The results demonstrated that hyperoside pretreatment for 2 h decreased cell apoptosis from 54.03±9.11 to 17.46±3.10% in the H2O2‑injured melanocytes. The levels of oxidative stress in the mitochondrial membrane potential of the melanocytes increased following hyperoside pretreatment. The mRNA and protein levels of B‑cell lymphoma‑2/Bcl‑2‑associated X protein and caspase 3 were regulated by hyperoside, and phosphoinositide 3‑kinase/AKT and mitogen‑activated protein kinase signaling were also mediated by hyperoside.
2.Paeonol enhances thrombus recanalization by inducing vascular endothelial growth factor 165 via ERK1/2 MAPK signaling pathway.
Ye S1, Liu X2, Mao B1, Yang L1, Liu N1. Mol Med Rep. 2016 Apr 15. doi: 10.3892/mmr.2016.5135. [Epub ahead of print]
Paeonol (2'-hydroxy-4'-methoxyacetophenone) is the major active compound of Mautan cortex and has been demonstrated to inhibit platelet aggregation in previous studies. The current study aimed to elucidate the underlying molecular mechanism of paeonol in recanalizing thrombi. The presence of indicators of prothrombotic state (PTS) in the serum of the model animals were determined by enzyme‑linked immunosorbent assay (ELISA) assay and the cytotoxicity of paeonol on human umbilical vein endothelial cell (HUVEC) cultures was estimated by 3‑(4,5 dimethylthiazol‑2‑yl)-2,5-diphenyltetrazolium bromide assay. The possible underlying signaling pathway involved in the interaction between paeonol and vascular endothelial growth factor 165 (VEGF165) was investigated using western blotting. The levels of 6‑keto‑prostaglandin F1α, fibronectin, and VEGF165 in serum were significantly upregulated by the treatment of paeonol while the levels of fibrinogen, D‑dimer, and thromboxane B2 were significantly downregulated (P<0.
3.Cellulose nanocrystal-poly(oligo(ethylene glycol) methacrylate) brushes with tunable LCSTs.
Grishkewich N1, Akhlaghi SP1, Zhaoling Y1, Berry R2, Tam KC3. Carbohydr Polym. 2016 Jun 25;144:215-22. doi: 10.1016/j.carbpol.2016.02.044. Epub 2016 Feb 18.
This paper reports on the synthesis of poly(oligoethylene glycol) methyl ether acrylate (POEGMA) grafted cellulose nanocrystals (CNCs) via surface initiated atom transfer radical polymerization (ATRP). An ATRP initiator (α-Bromoisobutyryl bromide) was covalently bonded to the surface of CNCs, followed by copolymerizing di(ethylene glycol) methyl ether methacrylate (MEO2MA) and oligoethylene glycol methyl ether methacrylate (OEGMA300) monomers from the surface using Cu(I)Br/2,2-dipyridal. Multiple POEGMA-g-CNC systems with varying MEO2MA/OEGMA300 content were synthesized, and they displayed a range of lower critical solution temperatures (LCSTs) in aqueous medium. μDSC endotherms and microstructural analysis indicated the collapse of POEGMA chains, followed by the aggregation of nanoparticles above their LCSTs. Cloud point measurements demonstrated a hysteresis in the heating and cooling of the POEGMA-g-CNC systems. It was found that the LCST of the nanoparticles could be tuned to between 23.