Anticoagulant Activity of Sulfated Schizophyllan

Sulfated schizophylians with lower anticoagulant activity and higher anti-HIV activity were prepared. Those with sulfur contents above 6% showed anticoagulant activity irrespective of molecular weight. The activity was correlated with sulfur content. The triple helical structure of sulfated schizophylians did not affect their anticoagulant activity. A sulfated schizophyllan with a sulfur content of 5.0% showed low anticoagulant activity and good anti-HIV activity. These results indicate that the latter sulfated schizophyllan (sulfur content, 5%) would be useful as an anti-HIV agent for treatment of HIV-infected hemophiliacs.     

In vitro anti-influenza virus activities of sulfated polysaccharide fractions from <Emphasis Type="Italic">Gracilaria lemaneiformis</Emphasis>

In this paper, in vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were investigated. Cytotoxicities and antiviral activities of Gracilaria lemaneiformis polysaccharides (PGL), Gracilaria lemaneiformis polysaccharide fraction-1 (GL-1), Gracilaria lemaneiformis polysaccharide fraction-2 (GL-2) and Gracilaria lemaneiformis polysaccharide fraction-3 (GL-3) were studied by the Methyl thiazolyl tetrazolium (MTT) method, and the inhibitory effect against Human influenza virus H1-364 induced cytopathic effect (CPE) on MDCK cells were observed by the CPE method. In addition, the antiviral mechanism of PGL was explored by Plaque forming unit (PFU), MTT and CPE methods. The results showed: i) Cytotoxicities were not significantly revealed, and H1-364 induced CPE was also reduced treated with sulfated polysaccharide fractions from Gracilaria lemaneiformis; ii) Antiviral activities were associated with the mass percentage content of sulfate groups in polysaccharide fractions, which was about 13%, in polysaccharides (PGL and GL-2) both of which exhibited higher antiviral activity; iii) A potential antiviral mechanism to explain these observations is that viral adsorption and replication on host cells were inhibited by sulfated polysaccharides from Gracilaria lemaneiformis. In conclusion, Anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were revealed, and the antiviral activities were associated with content of sulfate groups in polysaccharide fractions.     

Sea urchin arylsulfatase,an extracellular matrix component,is involved in gastrulation during embryogenesis

Arylsulfatases (Arses) have been regarded as lysosomal enzymes because of their hydrolytic activities on synthetic aromatic substrates and their lysosomal localization of their enzymatic activities. Using sea urchin embryos, we previously demonstrated that the bulk of Hemicentrotus Ars (HpArs) does not exhibit enzyme activity and is located on the apical surface of the epithelial cells co-localizing with sulfated polysaccharides. Here we show that HpArs strongly binds to sulfated polysaccharides and that repression of the synthesis by HpArs-morpholino results in retardation of gastrulation in the sea urchin embryo. Accumulation of HpArs protein and sulfated polysaccharides on the apical surface of the epithelial cells in sea urchin larvae is repressed by treatment with β-aminopropionitrile (BAPN), suggesting that deposition of HpArs and sulfated polysaccharides is dependent on the crosslinking of proteins such as collagen-like molecules. We suggest that HpArs functions by binding to components of the extracellular matrix.     

Controlled sulfatation of natural anionic bacterial polysaccharides can yield agents with specific regenerating activity in vivo

The regenerating activities of chemically modified anionic bacterial polysaccharides by O-sulfonation were investigated using a in vivo model of rat injured muscle regeneration. Glucuronan (GA), a linear homopolysaccharide of -->4)-beta-D-GlcpA-(1--> residues partially acetylated at the C-3 and/or the C-2 position, and glucoglucuronan (GGA), a linear heteropolysaccharide of -->3)-beta-D-GlcpA-(1-->4)-beta-D-Glcp-(1--> residues were sulfated. SO3-DMF sulfatation complex provided polysaccharides with different sulfur contents, however, a depolymerization occurred because we did not use large excess of pyridine to obtain pure modified polysaccharides. A regenerating activity on injured extensor digitorum longus (EDL) muscles on rats was obtained with these two sulfated anionic polymers. The position of sulfate groups on glucoglucuronan (primary or secondary alcohol) seems to have no influence on the biological activity by opposition to the degree of sulfatation both for the glucuronans and the glucoglucuronans. The yield of acetate groups in the glucuronan polymer modulated the specific activity.     

Effect of Sulfated Modification on the Molecular Characteristics and Biological Activities of Polysaccharides from Hypsizigus marmoreus

The effect of sulfated modification on polysaccharides from Hypsizigus marmoreus was examined by determining their molecular structures and bioactivities. The sulfation, which was implemented by using an orthogonal array design, produced polysaccharides with varying degrees of substitution (DS) ranging from 0.11 to 1.06. The sulfated polysaccharides exhibited a lower average molecular weight (M _w) and considerably higher radius of gyration (R _g) than those of native polysaccharide, suggesting that the conformation of the sulfated polysaccharides had been changed towards a more extended type. The inhibitory activity toward cancer cell growth was enhanced by treating with the sulfated polysaccharides by up to 34%, as compared to the native polysaccharide. In addition, treating with the sulfated polysaccharides increased the nitric oxide (NO) and cytokine (IL-1β and TNF-α) release to levels comparable to those detected in the positive control, lipopolysaccharide (LPS), suggesting that the sulfated polysaccharides might have strong immunomodulatory activity.     

Sulfated polysaccharides from brown seaweeds Saccharina japonica and Undaria pinnatifida: isolation, structural characteristics, and antitumor activity

During the last decade brown seaweeds attracted much attention as a source of polysaccharides, namely laminarans, alginic acids, and sulfated polysaccharides—fucoidans, with various structures and biological activities.In this study, sulfated polysaccharides were isolated from brown seaweeds Saccharina japonica (formerly named Laminaria) and Undaria pinnatifida and their antitumor activity was tested against human breast cancer T-47D and melanoma SK-MEL-28 cell lines.The sulfated polysaccharide form S. japonica was highly branched partially acetylated sulfated galactofucan, built up of (1→3)-α-l-fucose residues. The sulfated polysaccharide from U. pinnatifida was partially acetylated highly sulfated galactofucan consisting of (1→3)- or (1→3);(1→4)-α-l-fucose residues.Fucoidans from S. japonica and U. pinnatifida distinctly inhibited proliferation and colony formation in both breast cancer and melanoma cell lines in a dose-dependent manner. These results indicated that the use of sulfated polysaccharides from brown seaweeds S. japonica and U. pinnatifida might be a potential approach for cancer treatment.     

Antiviral Activities of Marine Pseudomonas Polysaccharides and Their Oversulfated Derivatives

A marine Pseudomonas species WAK-1 strain simultaneously produces extracellular glycosaminoglycan and sulfated polysaccharide. Among the antiviral activities tested for these polysaccharides, the latter showed anti-HSV-1 activity in RPMI 8226 cells (50% effective concentration is 1.4 μg/ml). Oversulfated derivatives of these polysaccharides prepared by dicyclohexylcarbodiimide-mediated reaction for both polysaccharides showed antiviral activities against influenza virus type A (for glycosaminoglycan, 50% effective concentration is 11.0 μg/ml; for another, 2.9 μg/ml). Glycosaminoglycan, sulfated polysaccharide, and their chemically synthesized oversulfated derivatives did not show antiviral activities against influenza virus type B and human immunodeficiency virus type 1. No cytotoxicity of these products was noted against host cells at the 50% cytotoxic concentration of 100 μg/ml, except that naturally occurring sulfated polysaccharide had 50% cytotoxicity against MT-4 cells at 8–21 μg/ml. Received May 1, 1998; accepted July 24, 1998.     

Study of antioxidant activities of sulfated polysaccharides from Laminaria japonica

The composition, molecular weight and in vitro antioxidant activity of various sulfated polysaccharides obtained by anion exchange chromatography, acid hydrolysis and radical process degradation of the crude sulfated polysaccharide extracted from Laminaria japonica were compared. The low sulfated F-A2, with a peak-molecular weight (Mp) of 5–15 kDa, 14.5% sulfated ester and 21.8% glucuronic acid, exhibited a very strong antioxidant activity on superoxide and hydroxyl radicals, with activity even higher than that of large molecular weight fractions F-A and F-B. However, highly sulfated fractions with a peak-molecular weight below 15 kDa had much lower antioxidant activities than other fractions. These results indicated that the sulfate group of the low molecular weight fractions represents a physical block for the reaction with oxygen radicals. The chemical properties and antioxidant activities of sulfated polysaccharide fractions obtained by radical process degradation of crude sulfated polysaccharide were quite different from those obtained by acid hydrolysates. By radical process degradation, the high molecular weight was decreased to give LM2 (Mp 8 kDa) and LM1 (Mp 1.5 kDa), with a yield of 40% and 15%, respectively. LM2 was enriched with fucose and sulfated ester, while containing low amounts of glucuronic acid. The antioxidant activity showed that LM2 was unable to scavenge either superoxide or hydroxyl radical, which suggested that radical process degradation targeted mainly ascopyllan-like species rich in glucuronic acid, while the fraction rich in sulfated l-fucose remained unchanged. However, LM1 with Mp 1.5 kDa still retained apparent scavenging ability for superoxide radical, although it contained no glucuronic acid and certain amounts of galactose and mannose as main neutral sugars. These result suggest that the antioxidant activity of sulfated polysaccharides is apparently related not only to molecular weight and sulfated ester content, as previously determined, but also to glucuronic acid and fucose content.     

Sulfated galactofucan from <Emphasis Type="Italic">Lobophora variegata</Emphasis>: Anticoagulant and anti-inflammatory properties

Sulfated polysaccharides (fucans and fucoidans) from brown algae show several biological activities, including anticoagulant and anti-inflammatory activities. We have extracted a sulfated heterofucan from the brown seaweed Lobophora variegata by proteolytic digestion, followed by acetone fractionation, molecular sieving, and ion-exchange chromatography. Chemical analyses and ¹³C-NMR and IR spectroscopy showed that this fucoidan is composed of fucose, galactose, and sulfate at molar ratios of 1:3:2. We compared the anticoagulant activity of L. variegata fucoidan with those of a commercial sulfated polysaccharide (also named fucoidan) from Fucus vesiculosus and heparin. The experimental inflammation models utilized in this work revealed that fucoidan from L. variegata inhibits leukocyte migration to the inflammation site. Ear swelling caused by croton oil was also inhibited when sulfated polysaccharides from F. vesiculosus and L. variegata were used. The precise mechanism of different action between homo-and heterofucans is not clear; nevertheless, the polysaccharides studied here may have therapeutic potential in inflammatory disorders. Published in Russian in Biokhimiya, 2008, Vol. 73, No. 9, pp. 1265–1273.     

Sulfated polysaccharides from marine green algae Ulva conglobata and their anticoagulant activity

Sulfated polysaccharides from the green algae Ulva conglobata were isolated and prepared by extraction in hot water, precipitation with ethanol and purification by ion-exchange and size-exclusion column chromatography. The characterizations of the sulfated polysaccharides were defined, and containing 23.04–35.20% sulfate ester groups, 10.82–14.91% uronic acid and 3.82–4.51% protein. Gas chromatography analysis shows that the sulfated polysaccharides from Ulva conglobata are mainly consisted of rhamnose with variable contents of glucose and fucose, trace amounts of xylose, glactose and mannose. The anticoagulant properties of the sulfated polysaccharides were compared with those of heparin by studying the activated partial thromboplastin time using normal human plasma. The sulfated polysaccharide from Ulva conglobata collected in Qingdao, China is the most potent among the sulfated polysaccharides tested. The mechanism of anticoagulant activity mediated by the sulfated polysaccharides is due to the direct inhibition of thrombin and the potentiation of heparin cofactor II.     

In Vitro Anti-influenza Virus Activities of Sulfated Polysaccharide Fractions from Gracilaria lemaneiformis

In this paper, in vitro anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were investigated. Cytotoxicities and antiviral activities of Gracilaria lemaneiformis polysaccharides (PGL), Gracilaria lemaneiformis polysaccharide fraction-1 (GL-1), Gracilaria lemaneiformis polysaccharide fraction-2 (GL-2) and Gracilaria lemaneiformis polysaccharide fraction-3 (GL-3) were studied by the Methyl thiazolyl tetrazolium (MTT) method, and the inhibitory effect against Human influenza virus H1-364 induced cytopathic effect (CPE) on MDCK cells were observed by the CPE method. In addition, the antiviral mechanism of PGL was explored by Plaque forming unit (PFU), MTT and CPE methods. The results showed: i) Cytotoxicities were not significantly revealed, and H1-364 induced CPE was also reduced treated with sulfated polysaccharide fractions from Gracilaria lemaneiformis; ii) Antiviral activities were associated with the mass percentage content of sulfate groups in polysaccharide fractions, which was about 13%, in polysaccharides (PGL and GL-2) both of which exhibited higher antiviral activity; iii) A potential antiviral mechanism to explain these observations is that viral adsorption and replication on host cells were inhibited by sulfated polysaccharides from Gracilaria lemaneiformis. In conclusion, Anti-influenza virus activities of sulfated polysaccharide fractions from Gracilaria lemaneiformis were revealed, and the antiviral activities were associated with content of sulfate groups in polysaccharide fractions.     

Synthesis of sulfated oligosaccharide glycosides having high anti-HIV activity and the relationship between activity and chemical structure.

Sulfated laminara-oligosaccharide glycosides having high anti-human immunodeficiency virus (HIV) activities were synthesized from laminara-tetraose, -pentaose and -hexaose. The oligosaccharide glycosides were synthesized by treating peracetylated beta-oligosaccharides with various alcohols and Lewis acid catalysts. The effects of the number of glucose residues and the alkyl chain-length on anti-HIV activity were examined. The anti-HIV activity of sulfated dodecyl laminara-pentaosides and -hexaosides increased with increasing degree of sulfation (DS) and the pentaoside having an almost fully-sulfated saccharide portion had the highest activity, whereas for the hexaoside a somewhat lower DS manifested the highest activity. Sulfated laminara-oligosaccharide glycosides having fluoroalkyl-containing aglycons of high hydrophobicity showed potent inhibitory effects against HIV infection. In contrast, hydrophilic substituents containing oligo(ethyleneoxy) groups as aglycons in the sulfated oligosaccharides did not show high anti-HIV activity.     

多糖抗病毒作用研究进展Ⅱ.硫酸多糖抗病毒作用

硫酸多糖的抗病毒活性,包括抗艾滋病毒HIV1活性,在近年得以阐明。本文综述了硫酸多糖的抗病毒作用、抗病毒机理及其构效关系。硫酸多糖具有广阔的临床应用前景,其抗病毒作用值得深入研究。     

Evaluating the possible anticoagulant and antioxidant effects of sulfated polysaccharides from the tropical green alga Caulerpa cupressoides var. flabellata

Seaweeds are a source of several biopolymers widely used in cosmetics, food, and pharmaceuticals. Among them are sulfated polysaccharides, which have several biological/pharmacological activities, such as antioxidant and anticoagulant activities. In the present study, four sulfated polysaccharides, denominated CCB-F0.3, CCB-F0.5, CCB-F1.0, and CCB-F2.0, were obtained from the chlorophyte Caulerpa cupressoides var. flabellata through proteolytic digestion, followed by acetone fractionation and molecular sieving in Sephadex G-100. Chemical analyses showed that CCB-F0.5 had the highest sulfate/sugar ratio (0.73), whereas CCB-F1.0 exhibited the lowest ratio (0.23). Polysaccharides from C. cupressoides displayed a heterogeneous constitution of monosaccharides, with galactose as the main sugar unit (except for CCB-F2.0). The presence of sulfated polysaccharides was confirmed by electrophoretic and infrared analyses. Sulfated polysaccharides showed no activity in superoxide and hydroxyl radical scavenging; however, they did demonstrate total antioxidant capacity and ferrous chelating activity. Caulerpa polysaccharides also exhibited anticoagulant activity in the intrinsic (activated partial thromboplastin time (aPTT) test) and extrinsic pathway (prothrombin time (PT) test). In the aPTT test, all polysaccharides displayed considerable dose-dependent activity. A significant result was the aPTT activity of the polysaccharides CCB-F0.3 and CCB-F0.5, which was similar to that of Clexane?, a commercial low molecular weight heparin. In addition, CCB-F0.3 and CCB-F0.5 showed PT activity. Sulfated polysaccharides from C. cupressoides are therefore promising antioxidant agents in preventing the formation of reactive oxygen species and for their possible use in anticoagulant therapy.     

Antiviral polysaccharides isolated from Hong Kong brown seaweed <Emphasis Type="Italic">Hydroclathrus clathratus</Emphasis>

Two relatively pure polysaccharides H3-a1 and H3-b1 had been isolated from the brown seaweed Hydroclathrus clathratus. They were characterized by HPLC, ultraviolet scanning, gas chromatography, infrared spectroscopy and elemental analysis, and shown to be two different sulfated polysaccharides with different monosaccharide content, but both with high relative molecular mass. They contained some proteins and uronic acid respectively. The sulfate content and bioactivity of these polysaccharides varied during purification. The fractions derived from the hot water extract also exhibited low anticoagulant effect. This is the first time that the antiherpetic and anticoagulant activities were evaluated for the polysaccharides from the Hong Kong brown seaweed Hydroclathrus clathratus.     

Sulfated polysaccharides from marine sponges: conspicuous distribution among different cell types and involvement on formation of in vitro cell aggregates

Marine sponges (Porifera) display an ancestral type of cell-cell adhesion, based on carbohydrate-carbohydrate interaction. The aim of the present work was to investigate further details of this adhesion by using, as a model, the in vitro aggregation of dissociated sponge cells. Our results showed the participation of sulfated polysaccharides in this cell-cell interaction, as based on the following observations: (1) a variety of sponge cells contained similar sulfated polysaccharides as surface-associated molecules and as intracellular inclusions; (2) ³⁵S-sulfate metabolic labeling of dissociated sponge cells revealed that the majority (two thirds) of the total sulfated polysaccharide occurred as a cell-surface-associated molecule; (3) the aggregation process of dissociated sponge cells demanded the active de novo synthesis of sulfated polysaccharides, which ceased as cell aggregation reached a plateau; (4) the typical well-organized aggregates of sponge cells, known as primmorphs, contained three cell types showing sulfated polysaccharides on their cell surface; (5) collagen fibrils were also produced by the primmorphs in order to fill the extracellular spaces of their inner portion and the external layer surrounding their entire surface. Our data have thus clarified the relevance of sulfated polysaccharides in this system of in vitro sponge cell aggregation. The molecular basis of this system has practical relevance, since the culture of sponge cells is necessary for the production of molecules with biotechnological applications.     

Micropattern immobilization of polysaccharide

Two types of polysaccharides, sulfated hyaluronic acid and heparin, were pattern-immobilized on a poly(ethylene terephthalate) and polystyrene film, respectively, in a specific pattern by photolithography. Sulfated hyaluronic acid was prepared from hylaronic acid by the treatment of sulfur trioxide/pyridine complex. Heparin was purchased and used without further treatment. The polysaccharides were coupled with azidoaniline. The derivatized polysaccharides were cast on a film from aqueous solution. After drying, the film was photo-irradiated in the presence or absence of a photomask. The micropatterning was confirmed by staining with a cationic dye. Platelet adhesion was reduced on the sulfated hyaluronic acid-immobilized areas. The immobilized sulfated hyaluronic acid significantly reduced thrombus formation. On the other hand, cells were cultured on the heparin-immobilized film. In the presence of fibroblast growth factor (FGF), the growth of mouse fibroblast STO cells was enhanced only on the heparin-immobilized regions. This result indicated that micropattern-immobilized heparin activated FGF for cell growth activity.     

Review: Prospects for the Use of Extracts and Polysaccharides from Marine Algae to Prevent and Treat the Diseases Caused by Helicobacter pylori

Helicobacter pylori possesses a broad spectrum of pathogenic factors that allow it to survive and colonize the gastric mucosa, and thus, the pathogenetic targets, which have the same diversity, require search for and the development of alternative, effective, and innocuous means for the eradication of H. pylori. In recent years, fucoidans have been extensively studied due to the numerous interesting biological activities, including the anti‐adhesive, anti‐oxidative, antitoxic, immunomodulatory, anticoagulant, and anti‐infection effects. This review summarizes the data on the effects of extracts and sulfated polysaccharides of marine algae, mainly fucoidans, on pathogenic targets in Helicobacter infection. The pathogenetic targets for therapeutic agents after H. pylori infection, such as flagellas, urease, and other enzymes, including adhesins, cytotoxin A (VacA), phospholipase, and L‐8, are characterized here. The main target for the sulfated polysaccharides of seaweed is cell receptors of the gastric mucosa. This review presents the published data about the pleiotropic anti‐inflammatory effects of polysaccharides on the gastric mucosa. It is known that fucoidan and other sulfated polysaccharides from algae have anti‐ulcer effects, prevent the adhesion of H. pylori to, and reduce the formation of biofilm. The authors speculate that the effect of sulfated polysaccharides on the infectious process caused by H. pylori is related to their action on innate and adaptive immunity cells, and also anti‐oxidant and antitoxic potential. Presented in the review are materials indicated for the study of extracts and sulfated polysaccharides from seaweed during H. pylori infection, as these compounds are characterized by multimodality actions. Based on the analysis of literary materials in recent years, the authors concluded that fucoidan can be attributed to the generation of new candidates to create drugs intended for the inclusion in the scheme of eradication therapy of H. pylori infection.     

Inhibitory effect of sulfated galactans from the marine alga Bostrychia montagnei on herpes simplex virus replication in vitro.

Sulfated polysaccharides exhibit many biological properties such as antiviral and anticoagulant activities. Herein, we report the antiviral activity of sulfated galactans extracted from the red sea-weed Bostrychia montagnei against herpes simplex virus types 1 (strain F and the thymidine kinase-deficient strains Field and B2006) and 2 (strain G). Two crude extracts obtained with cold and hot water as well as some fractions obtained by anion exchange chromatography, inhibited significantly the replication of the different strains of herpesviruses as determined by plaque reduction assays. The inhibitory effect of the compounds studied here took place only when they were added during the adsorption period. They were found to be highly selective antiviral substances, causing no impairment of Vero cell viability. Furthermore, they had no direct inactivating effect on virions by incubation in a virucidal assay. The antiviral activity could be correlated with the molecular weight and sulfate content of the polysaccharides. Although sulfated polysaccharides are generally endowed with anticoagulant properties, the results of the activated partial thromboplastin time and the thrombine time assays indicated that the natural sulfated polysaccharides from Bostrychia montagnei have very low anticoagulant activity, confirming that there is no relation between the antiviral and anticoagulant properties.     

Replication-competent gamma-retrovirus Mo-MuLV expressing green fluorescent protein as efficient tool for screening of inhibitors of retroviruses that use heparan sulfate as primary cell receptor

The effect of sulfated polysaccharides on the efficiency of the infection of mouse transplantable fibroblast SC-1 and NIH-3T3 cell lines by replication-competent recombinant Moloney murine leukemia virus (Mo-MuLV), which carries the eGFP gene, was investigated. It was found that sulfated polysaccharides have no cytostatic and cytotoxic effects on SC-1 and NIH-3T3 cells in the concentration range of 0.01–100 μg/mL and have virucidal activity against Mo-MuLV. Polysaccharides in the indicated concentrations inhibit Mo-MuLV infection that prevents the further development of viral infection. It was shown that sulfated polysaccharides are also effective inhibitors of other retroviruses, including lentiviruses, which use sulfated polysaccharides as primary cell receptors.