Antimicrobial hydrogels composed of chitosan and sulfated polysaccharides of red microalgae

Sulfated polysaccharides obtained from red microalgae proved to be as potent antiviral agents against various viruses. The huge molecular weight of these polysaccharides contributed much to the difficulty in explaining and understanding the mechanism of their activity against internal steps in the replication cycle of these viruses. In the present study we used microscopic Fourier-Transform Infrared Spectroscopy (FTIR) to investigate: (a) possible penetration of these polysaccharides into the treated cells, (b) effect of the polysaccharides treatment on some metabolic changes in these cells. Our results show a rapid accumulation of carbohydrates in the treated Vero cells. The carbohydrates level in these cells increases continuously after treatment during the entire experiment time period. In addition, we noted a gradual shift of PO2-ionized symmetric stretching peak of Vero cells to the position found in primary cells as a result of the continuous treatment with the microalgal polysaccharides.

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The Fine Structure of the Sheath of Volvox Carteri f. Weismannia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079231 ◽

1977 ◽

Vol 35 ◽

pp. 346-347

Author(s):

Regina Birchem

Keyword(s):

Developmental Stages ◽

Ruthenium Red ◽

Sulfated Polysaccharides ◽

Volvox Carteri ◽

High Voltage Electron Microscopy ◽

Ultrastructural Studies ◽

Voltage Electron ◽

Sheath Formation ◽

And Inversion ◽

Sheath Material

Spheroids of the green colonial alga Volvox consist of biflagellate Chlamydomonad-like cells embedded in a transparent sheath. The sheath, important as a substance through which metabolic materials, light, and the sexual inducer must pass to and from the cells, has been shown to have an ordered structure (1,2). It is composed of both protein and carbohydrate (3); studies of V. rousseletii indicate an outside layer of sulfated polysaccharides (4).Ultrastructural studies of the sheath material in developmental stages of V. carteri f. weismannia were undertaken employing variations in the standard fixation procedure, ruthenium red, diaminobenzidine, and high voltage electron microscopy. Sheath formation begins after the completion of cell division and inversion of the daughter spheroids. Golgi, rough ER, and plasma membrane are actively involved in phases of sheath synthesis (Fig. 1). Six layers of ultrastructurally differentiated sheath material have been identified.

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Further Studies on the Mechanisms for the Antithrombotic Effects of Sulfated Polysaccharides in Rabbits

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647027 ◽

1988 ◽

Vol 60 (02) ◽

pp. 188-192 ◽

Cited By ~ 15

Author(s):

F A Ofosu ◽

F Fernandez ◽

N Anvari ◽

C Caranobe ◽

F Dol ◽

...

Keyword(s):

Antithrombin Iii ◽

Ex Vivo ◽

Thrombus Formation ◽

Minimum Weight ◽

Sulfated Polysaccharides ◽

Pentosan Polysulfate ◽

Heparin Cofactor Ii ◽

Thrombin Inhibition ◽

The Relationship ◽

Prothrombin Activation

SummaryA recent study (Fernandez et al., Thromb. Haemostas. 1987; 57: 286-93) demonstrated that when rabbits were injected with the minimum weight of a variety of glycosaminoglycans required to inhibit tissue factor-induced thrombus formation by —80%, exogenous thrombin was inactivated —twice as fast in the post-treatment plasmas as the pre-treatment plasmas. In this study, we investigated the relationship between inhibition of thrombus formation and the extent of thrombin inhibition ex vivo. We also investigated the relationship between inhibition of thrombus formation and inhibition of prothrombin activation ex vivo. Four sulfated polysaccharides (SPS) which influence coagulation in a variety of ways were used in this study. Unfractionated heparin and the fraction of heparin with high affinity to antithrombin III potentiate the antiproteinase activity of antithrombin III. Pentosan polysulfate potentiates the activity of heparin cofactor II. At less than 10 pg/ml of plasma, all three SPS also inhibit intrinsic prothrombin activation. The fourth agent, dermatan sulfate, potentiates the activity of heparin cofactor II but fails to inhibit intrinsic prothrombin activation even at concentrations which exceed 60 pg/ml of plasma. Inhibition of thrombus formation by each sulfated polysaccharides was linearly related to the extent of thrombin inhibition achieved ex vivo. These observations confirm the utility of catalysis of thrombin inhibition as an index for assessing antithrombotic potential of glycosaminoglycans and other sulfated polysaccharides in rabbits. With the exception of pentosan polysulfate, there was no clear relationship between inhibition of thrombus formation and inhibition of prothrombin activation ex vivo.

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Faculty Opinions recommendation of Novel sulfated polysaccharides disrupt cathelicidins, inhibit RAGE and reduce cutaneous inflammation in a mouse model of rosacea.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718430977.793495885 ◽

2014 ◽

Author(s):

Uwe Wollina

Keyword(s):

Mouse Model ◽

Sulfated Polysaccharides ◽

Cutaneous Inflammation

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The Potential of Fucose-Containing Sulfated Polysaccharides As Scaffolds for Biomedical Applications

Current Medicinal Chemistry ◽

10.2174/0929867326666181213093718 ◽

2019 ◽

Vol 26 (35) ◽

pp. 6399-6411 ◽

Cited By ~ 2

Author(s):

Cláudia Nunes ◽

Manuel A. Coimbra

Keyword(s):

Tissue Regeneration ◽

Cell Walls ◽

Biomedical Applications ◽

Structural Features ◽

Therapeutic Agents ◽

Sulfated Polysaccharides ◽

Clinical Use ◽

Health Related ◽

Pathogen Inhibition ◽

Health Applications

Marine environments have a high quantity and diversity of sulfated polysaccharides. In coastal regions brown algae are the most abundant biomass producers and their cell walls have fucosecontaining sulfated polysaccharides (FCSP), known as fucans and/or fucoidans. These sulfated compounds have been widely researched for their biomedical properties, namely the immunomodulatory, haemostasis, pathogen inhibition, anti-inflammatory capacity, and antitumoral. These activities are probably due to their ability to mimic the carbohydrate moieties of mammalian glycosaminoglycans. Therefore, the FCSP are interesting compounds for application in health-related subjects, mainly for developing scaffolds for delivery systems or tissue regeneration. FCSP showed potential for these applications also due to their ability to form stable 3D structures with other polymers able to entrap therapeutic agents or cell and growth factors, besides their biocompatibility and biodegradability. However, for the clinical use of these biopolymers well-defined reproducible molecules are required in order to accurately establish relationships between structural features and human health applications.

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