Modulation of vascular function and anti-aggregation effect induced by (1 -> 3) (1 -> 6)-(beta-D-glucan of &ITSaccharomyces cerevisiae&IT and its carboxymethylated derivative in rats

Background: beta-D-GIucans are polysaccharides found in the cell walls of yeasts, such as Saccharomyces cerevisiae, and they have been studied because of their beneficial effects on health, mainly in terms of immunomodulation. However, information on the action of these polymers on vascular and platelet function is still scarce. This study evaluate the effect of (1 -> 3) (1 -> 6) beta-D-glucan (pG-Sc) and its carboxymethylated derivative (CM-G) on vascular and platelet function in rats. Methods: The animals received daily oral treatments with beta G-Sc (20 mg/kg) and CM-G (20 mg/kg) for eight days. Next, cytokine quantification, vascular reactivity and adenosine diphosphate (ADP)- and collagen-induced platelet aggregation studies were performed. In vitro platelet aggregation and P-selectin exposition assays were conducted using 100 and 300 mu g/mL CM-G. Results: The CM-G-treated group had less IL-8 than did the control. In reactivity experiments, CM-G and pG-Sc treatments did not change the contractile response of the vessel induced by PHE. Moreover, only CM-G improved the vasorelaxation response to Nitroprusside (SPN, a nitric oxide donor). The in vitro aggregation studies showed that at the highest concentration (300 mu g/mL), CM-G inhibited the agonist- induced platelet aggregation with an effect similar to that of acetylsalicylic acid and without affecting P-selectin exposition. The treatments with beta G-Sc or CM-G inhibited the platelet aggregation stimulated by ADP, but only beta G-Sc treatment was effective in affect the collagen-stimulated aggregation. Conclusions: These findings suggest that CM-G modulate positively the vascular function, mainly in responses NO-dependent. CM-G and beta G-Sc have an anti-aggregation effect, being CM-G more selective to ADP-induced platelet aggregation. (C) 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Sp. z o.o. All rights reserved.