Immunomodulatory Effects of Xylooligosaccharides

Abstract

Xylooligosaccharides (XOs) are considered as food ingredients, and exhibit the prebiotic effects related to gut modulation. However, no related research is available to explain their immunomodulatory effects. This report elucidated their immunomodulatory effects through the variations of proinflammatory mediators in vitro. We found that XOs (0.1 − 100 μg/mL) induced tumor necrosis factor alpha (TNF-α), IL-1β, IL-6 and nitric oxide (NO) production in un-stimulated macrophages, RAW264.7 cells. Furthermore, pre-and post-treated XOs (0.1 − 100 μg/mL) dose-dependently suppressed TNF-α, IL-1β, IL-6 and NO production and induced IL-10 production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells without exerting cytotoxicity. Of note is that prostaglandin E 2 (PGE 2 ) production didn't change significantly through the XOs treatment. These data demonstrate that XOs potently down-regulates the LPS-induced inflammatory response. The in vitro assessment of inflammatory mediators should be useful in further characterization of the effects of XOs on immunomodulation.

Engineering the Xylan Utilization System in Bacillus subtilis for Production of Acidic Xylooligosaccharides

“…Figure 6A shows the products generated by in vitro reaction with the recombinant XynC on the MeGX n used in the medium for the MR44 culture. XynC generated aldouronate products with m/z values that corresponded to those for the sodium salts of MeGX 4 to MeGX 18 and that were similar to those previously documented (16). Figure 6B shows the products accumulated by MR44 in the medium, with an m/z profile qualitatively similar to that observed for products generated by recombinant XynC in vitro.…”

“…Aldouronates, acidic xylooligosaccharides (U-XOS) containing one or more methylglucuronate residues linked ␣-1,2 to xylose residues in the ␤-1,4-xylan backbone in methylglucuronoxylans, have been shown to have a range of immunomodulating and antimicrobial activities (4,5,40,41). These have received increasing attention for additional applications, including the production of pentosan polysulfate (PPS).…”

“…In strain MR42, XynA is the only xylanase secreted, resulting in the expected limit for a GH11 endoxylanase of MeGX 4 . As seen in MALDI-TOF MS provided profiles supporting the common identities of the products generated by XynC and strain MR44, in which the gene encoding the GH11 XynA was deleted, indicating that XynC is the only endoxylanase activity other than XynA that is secreted by B. subtilis subsp.…”

“…Strain 168 showed the accumulation of MeGX 3 as the most prominent aldouronate, along with products with TLC mobilities corresponding to those of MeGX 4 and MeGX 5 , as well as small amounts of xylose (Fig. 5).…”

“…Neutral forms of these ␤-1,4-linked xylooligosaccharides have been reported to serve as prebiotics (1)(2)(3) and anti-inflammatory agents (4). Aldouronates, acidic xylooligosaccharides (U-XOS and U-AXOS, where U represents uronate) in which some xylose (X) residues are substituted with ␣-1,2-linked 4-O-methylglucuronate (MeG), have been shown to exhibit anti-inflammatory and other immunomodulating activities (5).…”