We also found a higher degree of genetic polymorphism in a non-waxy phenotype than in other low amylose types, supporting MK-2206 the hypothesis that low amylose types recently originated from non-waxy type.”
vera acemannan is a polysaccharide composed by a backbone of beta-(1 -> 4)-linked D-mannose residues interspersed by few glucose residues, acetylated in O-2,O-3, and O-6 containing side chains constituted by O-6-linked single alpha-D-galactose and alpha-L-arabinose residues. This structural features are rather similar to mannans from other sources, namely coffee and locust bean gum. However. Aloe vera acemannan and coffee mannans present immunostimulatory activity but locust bean gum does not. In order to know more about the structural features of a commercial HKI-272 order preparation of Aloe vera presenting comparable immunostimulatory activity to that observed for coffee mannans, this preparation was submitted to sugar and methylation analysis. To gain further
insight to the structural details of the mannans, focusing in the study of acetylation pattern, a specific hydrolysis with an endo-beta-(1 -> 4)-D-mannanase was performed and the resulting oligosaccharides (OS) were fractionated by size exclusion chromatography and characterized by ESI-MS, ESI-MS/MS and MALDI-MS. The majority of the OS obtained for acemannan had a ratio of two acetyl groups per sugar residue. The observation of OS highly acetylated as well as non-acetylated OS, allowed to infer a non-homogeneous distribution of the acetyl groups. Also, it was observed OS presenting fully acetylated arabinose residues.
The occurrence of a high abundance of acetylated residues shows that this polysaccharide contains odd acetylation content. These unusual features are reinforced by the presence of acetylated side chains, only previously observed in chemically acetylated mannans with immunostimulatory activity prepared from coffee residue. The comparison with other galactomannans allowed to infer that lower branching, ASP2215 cost shorter chains, and higher acetylation seems to promote the immunostimulatory activity attributed to these polysaccharides. (C) 2012 Elsevier Ltd. All rights reserved.”
“Th2 cytokines such as interleukin- 13 (IL- 13) have both, stimulatory and inhibitory effects on effector functions of macrophages. Reactive nitrogen species are classicaly induced in Th1 cytokines and/or lipopolysaccharides (LPS) activated macrophages and this response is inhibited by IL-13. In contrast, IL- 13 primes macrophages to produce NO in response to LPS when IL- 13 treatment happens prior to LPS exposure. This mechanism occurs through a complex signalling pathway, which involves the scavenger receptor CD36, the LPS receptor CD14 and the nuclear receptor PPAR gamma. The enhancement of NO production is the consequence of iNOS induction at mRNA and protein levels.