Enzymatically extracted ulvans restrict viruses via STING signaling and type I interferon after cellular entry.

Ulvans, abundant natural polysaccharides produced by Ulvales, have been recognized for antiviral activities, though the underlying mechanisms are not fully understood. In this study, we focused on two polysaccharides and one oligosaccharide, which were extracted enzymatically from Ulva prolifera and named as PR1 (13.5 kDa), PR2 (7.

Fucoidan MF4 from Fucus vesiculosus inhibits Lewis lung cancer via STING-TBK1-IRF3 pathway.

Fucoidan, a sulfated polysaccharide of marine origin found in brown algae and sea cucumbers, has been identified as a neuroprotective compound. In this study, a novel fucoidan MF4 was extracted from Fucus vesiculosus and isolated using Q-Sepharose fast-flow ion-exchange chromatography. The physicochemical properties of MF4 were characterized.

The STING-mediated antiviral effect of fucoidan from Durvillaea antarctica.

Fucoidans have attracted increasing attention due to their minimal toxicity and various biological activities, such as antioxidant, anti-inflammatory, anti-tumor and immunomodulatory effects. In this study, the antiviral effect and mechanism of fucoidan (FU) derived from Durvillaea antarctica were explored in vitro. The results demonstrated that FU effectively inhibited the infection of both RNA virus (VSV) and DNA virus (HSV-1).

Design and syntheses of a bimolecular STING agonist based on the covalent STING antagonist.

Cyclic GMP-AMP synthase and stimulator of interferon genes (cGAS-STING) signaling stimulators, an essential innate immunity component, monitor invading pathogen DNA and damaged self-DNA, making them an appealing target for drug development. The natural STING agonist, 2'3'-cGAMP, mounts and stabilizes the STING homodimer to trigger an antiviral or antitumor immune responses. However, cyclic-dinucleotide-based STING agonists show limited clinical effects owing to their short half-lives.

Silica Nanoparticles with Virus-Mimetic Spikes Enable Efficient siRNA Delivery In Vitro and In Vivo.

Oligonucleotide-based therapy has experienced remarkable development in the past 2 decades, but its broad applications are severely hampered by delivery vectors. Widely used viral vectors and lipid nanovectors are suffering from immune clearance after repeating usage or requiring refrigerated transportation and storage, respectively. In this work, amino-modified virus-mimetic spike silica nanoparticles (NH-SSNs) were fabricated using a 1-pot surfactant-free approach with controlled spike lengths, which were demonstrated with excellent delivery performance and biosafety in nearly all cell types and mice.

Chitosan coated pH/redox-responsive hyaluronic acid micelles for enhanced tumor targeted co-delivery of doxorubicin and siPD-L1.

The complex tumor microenvironment (TME) makes it difficult for single chemotherapy to achieve satisfactory therapeutic effects. Here, chitosan-coated hyaluronic acid micelles (R/C/D@HAssOA) that co-delivers doxorubicin (DOX) and programmed death-ligand 1 small interfering RNA (siPD-L1) are developed to enhance anti-tumor effect by combination of immunotherapy and chemotherapy. The pH/reduction dual-responsive co-delivery micelles R/C/D@HAssOA are spherical particles about 180 nm, and have good drug loading performance, stability, biocompatibility, and TME-responsive drug release properties.

Low molecular-weight polyguluronate phosphate: An immunostimulant by activating splenocyte/macrophage invitro and improving immune response invivo.

The substituents and backbones are two main factors affecting immune activities of polysaccharides. In the present study, we firstly evaluated the immunostimulating effects of phosphorylated, sulfated, H-phosphonated and nitrated derivatives of low-molecular-weight polymannuronate (LPM) and polyguluronate (LPG) on splenocytes and peritoneal macrophages in vitro. The results showed that the phosphate group was the best substituent to enhance the immune activities, and LPG phosphate (LPGP) had much better activity than LPM phosphate (LPMP).

Inhibition of Histone H3 Lysine-27 Demethylase Activity Relieves Rheumatoid Arthritis Symptoms Repression of IL6 Transcription in Macrophages.

Rheumatoid arthritis (RA) occurs in about 5 per 1,000 people and can lead to severe joint damage and disability. However, the knowledge of pathogenesis and treatment for RA remains limited. Here, we found that histone demethylase inhibitor GSK-J4 relieved collagen induced arthritis (CIA) symptom in experimental mice model, and the underlying mechanism is related to epigenetic transcriptional regulation in macrophages.

The anti-inflammatory activity of specific-sized hyaluronic acid oligosaccharides.

Severe acute inflammatory conditions may cause tissue damage, sepsis, and death. As a critical component of the extracellular matrix, hyaluronic acid (HA) has been reported to possess pro- and anti-inflammatory properties via Toll-like receptors (TLRs). In this study, we prepared different sizes and structures of HA oligosaccharides and derivatives and investigated the effects on inflammation in vitro and in vivo.

Alginate-chitosan oligosaccharide-ZnO composite hydrogel for accelerating wound healing.

Moist, breathable and antibacterial microenvironment can promote cell proliferation and migration, which is beneficial to wound healing. Here, we fabricated a novel sodium alginate-chitosan oligosaccharide‑zinc oxide (SA-COS-ZnO) composite hydrogel by spontaneous Schiff base reaction, using aldehydated sodium alginate (SA), chitosan oligosaccharide (COS), and zinc oxide (ZnO) nanoparticles, which can provide a moist and antibacterial environment for wound healing. The porosity and swelling degree of SA-COS-ZnO hydrogel are 80% and 150%, respectively, and its water vapor permeability is 682 g/m/24h.

Sulfated polymannuroguluronate TGC161 ameliorates leukopenia by inhibiting CD4 T cell apoptosis.

Polysaccharides have aroused considerable interest due to their diverse biological activities and low toxicity. In this study, we evaluated the effect of marine polysaccharide sulfated polymannuroguluronate (TGC161) on the leukopenia induced by chemotherapy. It is found that TGC161 ameliorates the leukopenia.

Application prospect of polysaccharides in the development of anti-novel coronavirus drugs and vaccines.

Since the outbreak of the novel coronavirus disease COVID-19, caused by the SARS-CoV-2 virus, it has spread rapidly worldwide and poses a great threat to public health. This is the third serious coronavirus outbreak in <20 years, following SARS in 2002-2003 and MERS in 2012. So far, there are almost no specific clinically effective drugs and vaccines available for COVID-19.

Preparation, Characterization, and Inhibition of Hyaluronic Acid Oligosaccharides in Triple-Negative Breast Cancer.

Hyaluronic acid (hyaluronan, HA) is a critical component of the extracellular matrix and plays an important biological function of interacting with different molecules and receptors. In this study, both odd- and even-numbered HA oligosaccharides (HAOs) with specific degrees of polymerization (DP) were prepared by different hydrochloric acid hydrolyses, and their structures were characterized by means of HPLC, ESI-MS, and NMR. The data show that the odd-numbered HAOs (DP3-11) have a glucuronic acid reducing end, while the even-numbered HAOs (DP2-10) have an -acetylglucosamine reducing end.

Epirubicin-loaded marine carrageenan oligosaccharide capped gold nanoparticle system for pH-triggered anticancer drug release.

Gold nanoparticles (AuNPs) and the pH stimuli-responsive drug delivery system have been extensively applied in cancer treatment. Carrageenan derived from marine red algae shows a promising application prospect for drug delivery as a nanomaterial for its biodegradability, abundance, and non-toxicity. Carrageenan oligosaccharide (CAO) was used as a biocompatible reductant for green synthesis of CAO-AuNPs, and the obtained CAO-AuNPs were further used as a delivery system for pH-triggered delivery of epirubicin (EPI).

Glycosaminoglycans from a Sea Snake (): Extraction, Structural Characterization and Antioxidant Activity.

Sea snakes have wide application prospects in medicine, health food and other fields. Several novel polysaccharides were successfully obtained from the skin and the meat of a sea snake (). The structures of polysaccharides LSP3 and LMP3, which were extracted and purified from , were determined to be new and highly heterogenic glycosaminoglycans (GAGs) by means of FT-IR, ESI-MS/MS and NMR.

Preparation and structural characterization of regioselective 4-O/6-O-desulfated chondroitin sulfate.

The sulfation pattern plays a crucial role in chondroitin sulfate (CS) biological activity, and preparation of CS with defined structure is essential for accurate pharmacological study. In this study, we focused on the preparation of regioselective 4-O/6-O-desulfated CS derived from porcine, employing a dimethyl sulfoxide-methanol (DMSO-MeOH) method and an N-methyl-N-(trimethylsilyl) -trifluoroacetamide (MTSTFA) method CS, respectively. Results showed that the sulfate at C4 position (4-O-S) of N-acetylgalactosamine (GalNAc) was selectively removed by the DMSO-MeOH method, and the sulfate at C6 position (6-O-S) of GalNAc was selectively removed by the MTSTFA method.