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A novel homogenous polysaccharide LPWF together with its three acid hydrolysis products LPWF1–3 were isolated and prepared from lotus plumule (germs of Nelumbo nucifera). LPWF was composed of rhamnose (Rha), arabinose (Ara), galactose (Gal), xylose (Xyl), and galacturonic acid (GalA) in the molar ratio of 7.3: 34.0: 7.0: 19.1: 32.6 with a molecular weight of 567.6 kDa. The structure of LPWF was elucidated by methylation and NMR analysis of LPWF1–3 and a follow-up structural assembling aided by high-resolution mass spectrometry mapping of oligosaccharides and ROSEY spectra. LPWF was characterized as an unusual pectin linked by rhamnogalacturonan I (RGI, composed of LPWF1–2) and xylogalacturonan (XGA, LPWF3). LPWF1 was an arabinan peeled from the RGI part with a 1,5-linked backbone branching on the O -2 position, while LPWF2 was the remaining part of RGI composed of Rha (36.1%), Gal (17.8%), and GalA (43.7%). LPWF3 was identified as the XGA part with a backbone of α-1,4-linked GalA and branches of mono-xylose substitutions on the O -3 of GalA. LPWF (25 μg/mL) demonstrated significant inhibitions on the expression of IL-1β, IL-6, and TNF-α in LPS-stimulated primary murine microglia cultures. LPWF1 and 2 showed selectively and significantly inhibitory activity against the expression of IL-1β. • Structure features of the pectin LPWF was determined by NMR and methylation. • Structural characterization of LPWF was elucidated by assembling three stepwise hydrolyzed fragments. • LPWF is speculated to be a linearly linked RGI and XGA pectin. • The pectin LPWF could significantly inhibit the expression of IL-1β, IL-6, and TNF-α. [ABSTRACT FROM AUTHOR]

Heparin, an old but first-line anticoagulant, has been used over a century. It is a heterogeneous, linear, highly sulfated, anionic glycosaminoglycan with a broad distribution in relative molecular weight and charge density. These structural properties allow heparin to selectively interact with multiple proteins, leading to heparin's various pharmacological functions, such as anticoagulant, anti-viral, anti-tumor and anti-inflammatory activities. Clinical data suggest that unfractionated heparin or low molecule weight heparin could decrease mortality in COVID-19 patients with sepsis-induced hypercoagulation through the anticoagulant, anti-viral and anti-inflammatory activities of these drugs. Thus, the non-anticoagulant activity of heparin has again aroused attention. This review highlights recent advances in the preparation of heparin-derived drugs and clinical research on its non-anticoagulant properties over the past decade, to further the development and utilization of these important drugs. [Display omitted] [ABSTRACT FROM AUTHOR]

Polyguluronic acid (PG) is a type of polysaccharide found in edible brown seaweeds. This study synthesized a new sulfated saccharide (SOGA) by sulfating PG-derived unsaturated oligoguluronic acid (OGA). The molecular weight and degree of sulfate-group substitution of SOGA were 1.6 kDa and 1.03, respectively. The structures of PG, OGA, and SOGA were elucidated using FT-IR and NMR spectroscopy. Furthermore, the immunomodulatory effects of PG, OGA, and SOGA on LPS-triggered RAW264.7 and BV2 cells were evaluated. SOGA, but not PG or OGA, significantly reduced the LPS-stimulated overproduction of proinflammatory mediators and suppressed the activation of corresponding signalling pathways. Also, SOGA could actively regulate immune balance by inhibiting apoptosis and pyroapoptosis. These results suggested that SOGA is a potential therapeutic agent for the prevention of diseases associated with immune disorders owing to its remarkable immunomodulatory effects, and that sulfate groups in the carbohydrate chain play a crucial role for its bioactivities. [Display omitted] [ABSTRACT FROM AUTHOR]

Low molecular weight heparins (LMWHs), depolymerized from unfractionated heparin (UFH), are widely used as anticoagulant drugs in clinic. The variable degradation methods result the different types of LMWHs, such as enoxaparin prepared by alkaline degradation following benzylation and nadroparin degraded by nitrous acid and subsequent reduction. They have different anticoagulant activities, molecular weight and special oligosaccharide sequences. Oligosaccharide analysis of the heparinase-catalyzed digestion products of heparin and LMWHs is an important way to explore the fine structural composition. In this work, a MHC-2D-LC-MS system using SAX followed by SEC and tandem to MS was applied to analyze the heparinase-products of LMWHs. 15 components of enoxaparin and 20 components of nadroparin were separated and unambiguously characterized with mass spectrum, including eight common disaccharides, and the special structural domains resistant to enzyme digestion which have the 3- O sulfated residue and/or characteristic terminal residues and the linkage region tetrasaccharides. • The platform of MHC 2D-LC linked to MS was applied to analyze digested LMWHs. • SAX is the first dimensional, SEC is the second dimensional chromatography. • 15 and 20 structural domains in enoxaparin and nadroparin were identified. • Common structural framework and special structural domains were observed. [ABSTRACT FROM AUTHOR]