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Structurally different water-insoluble (1→3),(1→6) β-D-glucans were isolated from aqueous and alkaline extracts of the mushroom-forming ascomycete Cookeina tricholoma, a wild edible mushroom found in Brazilian Amazon forest. The structures showed different substitution patterns, which may influence their extractability and consequently their conformation in solution, and different MW (4.3×10(5)Da, 3.7×10(5)Da and 8.2×10(5)Da, for ICW-Ct, IHW-Ct and IK2-Ct, respectively). The main-chains are composed of (1→3)-linked β-D-Glcp units O-6 substituted by side chains with different lengths of (1→6)-linked β-d-Glcp units (ICW-Ct and IHW-Ct) or by a combination of (1→6)-linked β-D-Glcp units and single units of β-D-Glcp (IK2-Ct). β-D-glucans with similar MW and showing only (1→6)-linked β-D-Glcp units as side chains (ICW-Ct and IHW-Ct) showed significant inhibition of neurogenic pain, 69±11 and 57±11% at the dose of 10mgkg(-1), respectively, in the model of nociception induced by intraplantar injection of formalin., (Copyright © 2016. Published by Elsevier Ltd.)

A glucan was extracted with hot water from the basidiomycete Pleurotus pulmonarius and shown to have a (1-->3)-linked beta-D-glucopyranosyl main-chain substituted at O-6 of every third unit by single beta-D-glucopyranosyl non-reducing end units. This was shown by mono- and bidimensional nuclear magnetic resonance (NMR) spectroscopy, methylation analysis, and a controlled Smith degradation. The glucan was tested for its effects on the acetic acid-induced writhing reaction in mice, a typical model for quantifying inflammatory pain. It caused a marked and dose-dependent anti-inflammatory response, demonstrated by the inhibition of leukocyte migration to injured tissues (82 +/- 6%) with an ID50 of 1.19 (0.74-1.92) mg/kg. Furthermore, animals previously treated with the glucan (3 mg/kg i.p.), showed a reduction of 85 +/- 5% of writhes, after receiving the acetic acid injection. Furthermore, in the formalin test, the glucan (3-30 mg/kg, i.p.) also caused significant inhibition of both the early (neurogenic pain) and the late phases (inflammatory pain) of formalin-induced licking. However, it was more potent and effective in relation to the late phase of the formalin test, with mean ID(50) values for the neurogenic and the inflammatory phases of > 30 and 12.9 (6.7-24.6) mg/kg and the inhibitions observed were 43 +/- 5% and 96 +/- 4%, respectively. These data showed that the glucan had potent anti-inflammatory and analgesic (antinociceptive) activities, possibly by the inhibition of pro-inflammatory cytokines.

The Ascomycete Cordyceps militaris, an entomopathogenic fungus, is one of the most important traditional Chinese medicines. Studies related to its pharmacological properties suggest that this mushroom can exert interesting biological activities. Aqueous (CW and HW) and alkaline (K5) extracts containing polysaccharides were prepared from this mushroom, and a β-D-glucan was purified. This polymer was analysed by GC-MS and NMR spectrometry, showing a linear chain composed of β-D-Glcp (1→3)-linked. The six main signals in the 13C-NMR spectrum were assigned by comparison to reported data. The aqueous (CW, HW) extracts stimulated the expression of IL-1β, TNF-α, and COX-2 by THP-1 macrophages, while the alkaline (K5) extract did not show any effect. However, when the extracts were added to the cells in the presence of LPS, K5 showed the highest inhibition of the pro-inflammatory genes expression. This inhibitory effect was also observed for the purified β-(1→3)-D-glucan, that seems to be the most potent anti-inflammatory compound present in the polysaccharide extracts of C. militaris. In vivo, β-(1→3)-D-glucan also inhibited significantly the inflammatory phase of formalin-induced nociceptive response, and, in addition, it reduced the migration of total leukocytes but not the neutrophils induced by LPS. In conclusion, this study clearly demonstrates the anti-inflammatory effect of β-(1→3)-D-glucan. [ABSTRACT FROM AUTHOR]