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Cancer is a complex disease, and blocking tumor angiogenesis has become one of the most promising approaches in cancer therapy. Here, an exopoly heteropolysaccharide (AQP70-2B) was firstly isolated from Akebia quinata. Monosaccharide composition indicated that the AQP70-2B was composed of rhamnose, glucose, galactose, and arabinose. The backbone of AQP70-2B consisted of →1)-l-Araf, →3)-l-Araf-(1→, →5)-l-Araf-(1→, →3,5)-l-Araf-(1→, →2,5)-l-Araf-(1→, →4)-d-Glcp-(1→, →6)-d-Galp-(1→, and →1)-d-Rhap residues. Based on the close relationship between selenium and anti-tumor activity, AQP70-2B was modified with selenium to obtain selenized polysaccharide Se-AQP70-2B. Then, a series of methods for analysis and characterization, especially scanning electron microscopy coupled with energy dispersive spectrometry (SEM-EDS), indicated that Se-AQP70-2B was successfully synthesized. Furthermore, zebrafish xenografts and anti-angiogenesis experiments indicated that selenization could improve the antitumor activity by inhibiting tumor cell proliferation and migration and blocking angiogenesis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A homogeneous polysaccharide, EJP90-1, was isolated from the leaves of E. japonica by hot water extraction in this study. EJP90-1 (7702 Da) was a heteropolysaccharide mainly consisting of →5)-linked-α-L-Araf-(1→, →4)-linked-β-D-Manp-(1→, →2,4)-linked-α-L-Rhap-(1→, →4)-linked-α-D-Xylp-(1→, →4)-linked-β-D-Galp-(1→, →2)-linked-β-D-Galp-(1→, →6)-linked-β-D-Glcp-(1→, α-D-Glcp-(4→, and t-linked-α-L-Araf. EJP90-1 was found to show moderate anti-tumor activity at the cellular level. In order to improve the anti-tumor activity and the potential applications of EJP90-1, a typical sodium selenite-nitric acid (Na 2 SeO 3 -HNO 3 ) modification on EJP90-1 was carried out. X-ray photoelectron spectroscopy (XPS) and energy dispersive spectrometer (EDS) analysis confirmed that Se was successfully introduced into the polymer chain of EJP90-1. The subsequent in vitro cytotoxicity evaluation showed the selenylation modification derivative (EJP90-1-Se) possessed significant antiproliferative activity against cancer cells (HepG2 and A549 cells) through inducing cell apoptosis. The anti-tumor activity of EJP90-1-Se was further confirmed by zebrafish models, which inhibited the proliferation and migration of HepG2 cells and the angiogenesis., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In this study, an inulin fructan (TMP50-2) with moderate anti-tumor activity was obtained from dandelion. To further improve the anti-tumor activity of TMP50-2, a monodisperse and stable spherical nanoparticle (Tw-TMP-SeNP, 50 nm) was fabricated. Physico-chemical analysis revealed that TMP50-2 and Tween 80 were tightly wrapped on the surface of SeNPs by forming CO⋯Se bonds or through hydrogen bonding interaction (OH⋯Se). In vitro anti-tumor assay showed that Tw-TMP-SeNP treatment could significantly inhibit the proliferation of cancer cells (HepG2, A549, and HeLa) in a dose-dependent manner, while HepG2 cells were more susceptible to Tw-TMP-SeNP with an IC 50 value of 46.8 μg/mL. The apoptosis induction of HepG2 cells by Tw-TMP-SeNP was evidenced by increasing the proportion of apoptotic cells ranging from 12.5% to 27.4%. Furthermore, in vivo zebrafish model confirmed the anti-tumor activity of Tw-TMP-SeNP by inhibiting the proliferation and migration of tumor cells as well as the angiogenesis of zebrafish embryos., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A water-soluble polysaccharide identified here as ADP80-2 was acquired from Angelica dahurica. ADP80-2 was a gluco-arabinan composed of arabinose and a trace of glucose with a molecular weight of 9950 g/mol. The backbone of ADP80-2 comprised →5)-α-L-Araf-(1→, →3, 5)-α-L-Araf-(1→, →6)-α-D-Glcp-(1→, with a terminal branch α-L-Araf-(1 → residue. In terms of immunoregulatory activity, ADP80-2 can significantly promote the phagocytosis, the production of nitric oxide (NO), and the secretion of cytokines (IL-6, IL-1β, and TNF-α) of macrophage. In addition to the cellular immunomodulatory activities, the chemokines related to immunoregulation were significantly increased in the zebrafish model after treated with ADP80-2. These biological results indicated that ADP80-2 with immunomodulatory effects was expected to be useful for the development of new immunomodulatory agents. Simultaneously, the discovery of ADP80-2 further revealed the chemical composition of A. dahurica used as a traditional Chinese medicine and spice., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In our continuous searching for natural active polysaccharides with immunomodulatory activity, an arabinofuranan (AQP70-3) was isolated and purified from the fruits of Akebia quinata (Houtt.) Decne. by using ion-exchange chromatography and gel permeation chromatography for the first time. AQP70-3 contained both α-l-Araf and β-l-Araf, and the absolute molecular weight was 1.06 × 10 4 g/mol. The backbone of AQP70-3 comprised →5)-α-l-Araf-(1→, →3,5)-α-l-Araf-(1→, and →2,5)-α-l-Araf-(1→, with branches of →1)-β-l-Arafand →3)-α-l-Araf-(1→ residues. Biological assay suggested that AQP70-3 can stimulate phagocytic activity and promote the levels of nitric oxide (NO), interleukin (IL)-6, IL-1β, and tumor necrosis factor-α (TNF-α) of RAW264.7 cells. Furthermore, AQP70-3 was found to increase the production of reactive oxygen species (ROS) and NO in zebrafish embryo model., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In our search for bioactive polysaccharides as immunomodulatory agents, an arabinofuranan (GMP90-1) was purified and characterized from the rinds of Garcinia mangostana L. GMP90-1 (absolute molecular weight: 5.30 × 10 3 g/mol) was found to be composed of arabinose, galactose, and rhamnose. The backbone of GMP90-1 was determined as (1→5)-linked α-l-Araf, (1→2,3,5)-linked α-l-Araf, (1→3,5)-linked α-l-Araf, (1→6)-linked β-d-Galp, and (1→2)-linked α-l-Rhap. Conformational analysis revealed GMP90-1 to exist as a rigid rod structure in sodium chloride solution. To explore its potential as immunomodulatory agents, an in vitro cell screening was performed and GMP90-1 was found to significantly enhance the phagocytic uptake of neutral red and improve the secreted level of nitric oxide (NO), interleukin (IL)-6, IL-1β, and tumor necrosis factor-α (TNF-α) of macrophages. Furthermore, the cellular immunomodulatory activities were confirmed by the in vivo zebrafish experiment, which suggested that GMP90-1 with immunomodulatory effects could be considered as a potential immunomodulatory for immune diseases., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A novel polysaccharide (ILP50-2) was extracted, isolated and purified from the leaves of Ilex latifolia Thunb. Its structure was characterized as a repeating unit consisting of α-L-Araf-(1→, →3)-α-L-Araf-(1→, →5)-α-L-Araf-(1→, →3,5)-α-L-Araf-(1→, →2)-α-L-Rhap-(1→, →2,4)-α-L-Rhap-(1→, β-D-Galp-(1→, →4)-β-D-Galp-(1→, →4)-β-D-Glcp-(1→, →6)-α-D-Manp-(1→, and →3,6)-α-D-Galp-(1→. The absolute molecular weight of ILP50-2 was 1.49 × 10 5 g/mol, which adapted a compact coil conformation in 0.1 M NaCl solution with R z of 25.4 nm. Furthermore, ILP50-2 exhibited immunoregulatory activity, mainly through enhancing the phagocytosis ability of macrophages and prompting the release of nitric oxide (NO) and cytokines tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β). Simultaneously, ILP50-2 was found to significantly increase the release of ROS and NO in zebrafish embryos, showing immunoregulatory effects in vivo., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)