1.
Structural characterization of a polysaccharide from Radix Hedysari and its protective effects against H2O2-induced injury in human gastric epithelium cells.
Xue, Z, Zhao, L, Wang, D, Chen, X, Liu, D, Liu, X, Feng, S
International journal of biological macromolecules. 2021;:503-515
Abstract
The gastroprotective effects of polysaccharides had become a hot topic in the field of functional polysaccharides research. Three polysaccharides, namely HPS-80-1, HPS-80-2, and HPS-80-3 were purified by DEAE-52 column chromatography. The thermodynamic characteristics, scanning electron microscopy, and Congo red experimental results of the above polysaccharides were greatly distinctive. Then a mature GES-1 oxidative stress cell model induced by H2O2 was established to screen out subsequent research subjects. It turned out that HPS-80-1 had a desirable protective effect, which was confirmed by analyses of cell cycle & apoptosis, and oxidative stress-related factors in the cell culture media, and so on. Furthermore, Structural features demonstrated that the backbone of HPS-80-1 appeared to mainly consist of →4)-α-D-Glcp-(1→, →4,6)-β-L-Glcp-(1→, and →6)-α-D-Galp-(1→, with branches at O-1, O-4, and O-6 position consisting of →2,4)-β-D-Rhap-(1→, →1)-α-D-Galp-(4→, and →3,4)-α-D-Manp-(1→. It was speculated that the excellent gastric mucosal protective activity of HPS-80-1 may be due to the high amount of glucose in the backbone. In addition, it was also related to the anti-inflammatory activity and antioxidant bases such as (1 → 4)-Glcp and (1 → 6)-Galp in the structure of HPS-80-1. These findings provide a scientific basis for further utilization of polysaccharides from Radix Hedysari.
2.
Manipulating Intratumoral Fenton Chemistry for Enhanced Chemodynamic and Chemodynamic-Synergized Multimodal Therapy.
Zhou, Y, Fan, S, Feng, L, Huang, X, Chen, X
Advanced materials (Deerfield Beach, Fla.). 2021;(48):e2104223
Abstract
Chemodynamic therapy (CDT) uses the tumor microenvironment-assisted intratumoral Fenton reaction for generating highly toxic hydroxyl free radicals (•OH) to achieve selective tumor treatment. However, the limited intratumoral Fenton reaction efficiency restricts the therapeutic efficacy of CDT. Recent years have witnessed the impressive development of various strategies to increase the efficiency of intratumoral Fenton reaction. The introduction of these reinforcement strategies can dramatically improve the treatment efficiency of CDT and further promote the development of enhanced CDT (ECDT)-based multimodal anticancer treatments. In this review, the authors systematically introduce these reinforcement strategies, from their basic working principles, reinforcement mechanisms to their representative clinical applications. Then, ECDT-based multimodal anticancer therapy is discussed, including how to integrate these emerging Fenton reinforcement strategies for accelerating the development of multimodal anticancer therapy, as well as the synergistic mechanisms of ECDT and other treatment methods. Eventually, future direction and challenges of ECDT and ECDT-based multimodal synergistic therapies are elaborated, highlighting the key scientific problems and unsolved technical bottlenecks to facilitate clinical translation.
3.
Intrinsic peroxidase-like catalytic activity of nitrogen-doped graphene quantum dots and their application in the colorimetric detection of H2O2 and glucose.
Lin, L, Song, X, Chen, Y, Rong, M, Zhao, T, Wang, Y, Jiang, Y, Chen, X
Analytica chimica acta. 2015;:89-95
Abstract
In this paper, the highly intrinsic peroxidase-like catalytic activity of nitrogen-doped graphene quantum dots (N-GQDs) is revealed. This activity was greatly dependent on pH, temperature and H2O2 concentration. The experimental results showed that the stable N-GQDs could be used for the detection of H2O2 and glucose over a wide range of pH and temperature, offering a simple, highly selective and sensitive approach for their colorimetric sensing. The linearity between the analyte concentration and absorption ranged from 20 to 1170 μM for H2O2 and 25 to 375 μM for glucose with a detection limit of 5.3 μM for H2O2 and 16 μM for glucose. This assay was also successfully applied to the detection of glucose concentrations in diluted serum and fruit juice samples.