Enhanced production of inducible nitric oxide synthase by β-glucans in mice

Abstract

We have already demonstrated that various activities including NO (nitric oxide) synthesis in vivo and in vitro significantly differ between triple helical (SPG) and single helical (alkaline-treated SPG, SPG-OH) beta-glucans. It was previously suggested that the single helical conformer of beta-glucan (SPG-OH) was dominant in cytokine production and subsequent NO synthesis in vitro. In this study, we analyzed production of inducible nitric oxide synthase (iNOS) induced by beta-glucans in vitro and in vivo. The iNOS production was enhanced in proteose peptone-induced peritoneal macrophages (PMs) cultured with SPG-OH in the presence of IFN-gamma for 24 h, and SPG-OH-induced PMs. Moreover, SPG-OH was effective for iNOS production not only in isolated macrophages but also in tissue macrophages, whereas SPG was less effective. These findings suggest that a single helical conformer is essential for iNOS production, and that NO synthesis by beta-glucans is closely related to iNOS production.

Time and concentration dependency of MacroGard® induced apoptosis

“…In both mammals and fish, β-glucan recognition results in the activation of macrophages, which induces phagocytosis, leukocyte migration and the production of cytokines (e.g. IL-1, TNFα), nitric oxide (NO) and reactive oxygen species, as well as the enhancement of complement activity [9][10][11][12][13][14][15][16][17].…”

β-Glucan from Lentinus edodes Inhibits Nitric Oxide and Tumor Necrosis Factor-α Production and Phosphorylation of Mitogen-activated Protein Kinases in Lipopolysaccharide-stimulated Murine RAW 264.7 Macrophages

“…Currently, another two important ␤-glucans, Schizophyllan (SPG) 3 and Lentinan (LNT), having the main chain of (1,3)-␤-glucan with one ␤-(1,6)-glucose branch at every five main-chain glucose residues are clinically used as antitumor agents (22,23). Yadomae and co-workers have demonstrated that SPG could not enhance NO or TNF-␣ secretion, but the alkaline-treated SPG (SPG-OH) could induce NO and TNF-␣ synthesis in vitro and in vivo (24,25). Moreover, SPG-OH augmented NO production in the presence of cytokines such as TNF-␣, IL-1␣, IL-6, GM-CSF, especially in the presence of interferon-␥ (IFN-␥) in vitro.…”

Hepatoprotective Effects of Paramylon, a .BETA.-1,3-D-Glucan Isolated from Euglena gracilis Z, on Acute Liver Injury Induced by Carbon Tetrachloride in Rats

“…-glucans are acknowledged to be one of the immune response modifiers [6]. Studies conducted over the past decade have shown that -glucans inhibit tumor development [28,38], enhance defense against bacterial infection [15,24], activate macrophages [8], induce production of cytokines [10,34], nitric oxide (NO) and arachidonic acid metabolites [14,21], increase hematopoiesis [35], exert radioprotective effects [12], are effective against burns [9,37], improve wound healing by inducing the macrophage release of wound growth factors [40] and lower serum lipids [4,23]. Among the several mechanisms proposed for the protective effects of -glucans, the major one is related to antioxidant capacity of the molecules [1,20], which has been further proven by Kogan et al [16] using electron paramagnetic response spectroscopy.…”