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The present study evaluated the antinociceptive effect of (1-->3),(1-->6)-linked [beta]-glucan (GL) isolated from Pleurotus pulmonarius (Fr.) Quel. in mice and its possible mechanism of action. Intraperitoneal administration of GL inhibited glutamate-induced licking with an ID(50) of 0.34 mg/kg and inhibition of 96% ± 3%. The treatment of animals with GL (1 mg/kg i.p.) inhibited nociception induced by intrathecal injection of N-methyl-D-aspartic acid, [alpha]-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, kainate and interleukin -1[beta] in 67% ± 13%, 89% ± 11%, 74% ± 9%, and 75% ± 7%, respectively, but not the nociceptive response induced by (±)-1-aminocyclopentane-trans-1,3-dicarboxylic acid, substance P, and tumor necrosis factor-[alpha]. Moreover, GL (30 mg/kg i.p.) also reduced mechanical allodynia caused by partial sciatic nerve ligation for 2 hours, with inhibition of 47% ± 10% observed 0.5 hours after treatment. When given chronically (twice a day) over 7 days, GL reversed the mechanical allodynia caused by partial sciatic nerve ligation (inhibition of 45% ± 13% to 60% ± 8%). Interestingly, GL did not affect the locomotor activity of mice in an open field test with doses that produce antinociceptive effects. Our findings show that GL inhibits acute and neuropathic pain in mice through mechanisms that involve the inhibition of ionotropic glutamate receptors and the interleukin -1[beta] pathway. PERSPECTIVE: This article presents the antinociceptive activity of GL in acute and neuropathic pain with participation of ionotropic glutamate receptors and pro-inflammatory cytokines (interleukin-1[beta]). After further experiments, this compound may represent a new pharmacological agent for the treatment of clinical pain. [ABSTRACT FROM AUTHOR]

Bacteria from the genus Herbaspirillum are endophytes responsible for nitrogen fixation in gramineous plants of economic importance such as maize, sugarcane, sorghum, rice, and wheat. Some species are known to produce plant growth substances. In contrast, Herbaspirillum rubrisubalbicans strains are known to be mild plant pathogens. The molecular communication between the plant and the microbes might involve lipopolysaccharides present in the outer membrane of these gram-negative bacteria. Phenol-water extraction was used to obtain lipopolysaccharides from 7 strains of Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95, and M2) and H. rubrisubalbicans (M1 and M4). The electrophoretic profiles and chemical composition of the lipopolysaccharides obtained in the phenol and aqueous extracts were shown herein. Les bactéries du genre Herbaspirillum sont des endophytes responsables de la fixation d’azote chez les graminées d’importance économique telles le maïs, la canne à sucre, le sorgho, le riz et le blé. Quelques espèces sont connues pour produire des substances favorisant la croissance végétale. Au contraire, les souches de Herbaspirillum rubrisubalbicans sont des pathogènes végétaux bénins. La communication moléculaire entre les végétaux et les microbes peut impliquer des lipopolysaccharides présents sur le membrane externe de ces bactéries négatives à gram. Une extraction phénol-eau a été utilisée pour obtenir les lipopolysaccharides de 7 souches de Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95 et M2) et de H. rubrisubalbicans (M1 et M4). Les profils en électrophorèse et la composition chimique des LPS obtenus des extraits phénoliques et aqueux sont présentés ici. [ABSTRACT FROM AUTHOR]

Abstract: Pulp from peaches contained polygalacturonic acid and arabinogalactan as main polysaccharides, which were isolated and characterised. The polygalacturonic acid (AE-CWI) contained 95% GalA and its 13C NMR spectrum showed signals at δ 98.9, 78.0, 71.4, 69.1, 68.4, and 175.1 from C-1, C-4, C-5, C-3, C-2, and C-6 respectively, from (1→4)-linked α-GalpA units. Methylation-MS analysis of carboxy-reduced material (AE-CWI-CR) gave 90% of 2,3,6-Me3-galactitol acetate. The arabinogalactan (AE-AG) was composed mainly of Ara (41%) and Gal (50%) and was characterised (methylation analysis and 13C NMR) as a type II-arabinogalactan. It induced peritoneal macrophage activation in mice, ∼70% of cells treated with this fraction (1–50μg/mL) having morphology of activated cells. However, NO production in macrophages treated with AE-AG was not affected. This suggests a new biological activity for peach polysaccharides. [Copyright &y& Elsevier]

Abstract: Cold aqueous extraction of basidiocarps (fruiting bodies) of the edible mushroom Lentinus edodes (shiitake) gave rise to a heteropolysaccharide, whose chemical structure, antinociceptive and anti-inflammatory properties were determined. Its chemical structure was based on monosaccharide composition, methylation analysis, and NMR spectroscopy (1H, 13C, HSQC, HSQC-TOCSY, HSQC-NOESY, and coupled HMQC). It was found to be a fucomannogalactan with a main chain of (1→6)-linked α-d-galactopyranosyl units, partially substituted at O-2 by single-unit β-d-Manp or α-l-Fucp side chains. The polysaccharide produced a marked and dose-related effect when assessed against acetic acid-induced visceral nociception. Prevention of peritoneal capillary permeability and leukocyte infiltration caused by the acetic acid was similar in potency and effectiveness. [Copyright &y& Elsevier]

Abstract: The gum exudate polysaccharide from the trunk of nectarine (PPNEC) was compared with that of peach, being composed of Ara, Xyl, Man, Gal, and uronic acids in 37:13:2:42:6 molar ratio and had M w 3.93×106 gmol−1, compared with 5.61×106 gmol−1 for peach gum polysaccharide. Methylation analysis of PPNEC indicated a highly branched structure with relatively high amounts of di- (16%) and tri-O-substituted (9%) Galp units and nonreducing end-units of Araf (26%) and Xylp (17%). Combination with 13C NMR data, showed the presence of α-l-Araf (nonreducing end, 3-O-, 5-O-, and 2,5-di-O-subst.), β-l-Arap (4-O- and 2,4-di-O-subst.), β-d-Galp (3-O-, 2,3-di-O-, 3,6-di-O-, and 3,4,6-tri-O-subst.), and α- and/or β-d-Xylp nonreducing end-units. A signal appeared from 4-O-Me-α-d-GlcpA units. PPNEC had structures similar to those of polysaccharide from peach tree gum, although in different proportions and with a lower M w. [Copyright &y& Elsevier]