Yeast ß-glucan-based nanoparticles loading methotrexate promotes osteogenesis of hDPSCs and periodontal bone regeneration under the inflammatory microenvironment.

The regeneration of absorbed alveolar bone and reconstruction of periodontal support tissue are huge challenges in the clinical treatment of periodontitis due to the limited regenerative capacity of alveolar bone. It is essential to regulate inflammatory reaction and periodontal cell differentiation. Based on the anti-inflammatory effect of baker's yeast ß-glucan (BYG) with biosafety by targeting macrophages, the BYG-based nanoparticles loading methotrexate (cBPM) were fabricated from polyethylene glycol-grafted BYG through chemical crosslinking for treatment of periodontitis. In our findings, cBPM promoted osteogenesis of human dental pulp stem cells (hDPSCs) under inflammatory microenvironment, characterized by the enhanced expression of osteogenesis-related Runx2 and activation of mitogen-activated protein kinase/extracellular signal-regulated protein kinase (MAPK/Erk) pathway in vitro. Animal experiments further demonstrate that cBPM effectively promoted periodontal bone regeneration and achieved in a better effect of recovery indicated by 19.2 % increase in tissue volume, 7.1 % decrease in trabecular separation, and a significant increase in percent bone volume and trabecular thickness, compared with the model group. Additionally, cBPM inhibited inflammation and repaired alveolar bone by transforming macrophage phenotype from inflammatory M1 to anti-inflammatory M2. This work provides an alternative strategy for the clinical treatment of periodontitis through BYG-based delivery nanoplatform of anti-inflammatory drugs.

Effect of the ß-glucan from Lentinus edodes on colitis-associated colorectal cancer and gut microbiota.

Colorectal cancer is the third most common cancer in the world, and therapies with safety are in great need. In this study, the ß-glucan isolated from Lentinus edodes was successfully fractionated into three fractions with different weight-average molecular weight (Mw) by ultrasonic degradation and used for the treatment of colorectal cancer. In our findings, the ß-glucan was successfully degraded with the Mw decreased from 2.56 × 106 Da to 1.41 × 106 Da, exhibiting the triple helix structure without conformation disruption. The in vitro results indicate that ß-glucan fractions inhibited colon cancer cell proliferation, induced colon cancer cell apoptosis, and reduced inflammation. The in vivo results based on Azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model demonstrate that the lower-molecular weight ß-glucan fraction showed stronger anti-inflammatory and anti-colon cancer activities by reconstructing intestinal mucosal barrier, increasing short chain fatty acids (SCFAs) content, regulating metabolism of gut microbiota, and rebuilding the gut microbiota structure with the increased Bacteroides and the decreased Proteobacteria at the phylum level, as well as with the decreased Helicobacter and the increased Muribaculum at the genus level. These findings provide scientific basis for using the ß-glucan to regulate gut microbiota as an alternative strategy in the clinical treatment of colon cancer.

Structural characteristics, biological, rheological and thermal properties of the polysaccharide and the degraded polysaccharide from raspberry fruits.

A native polysaccharide (RCPI) with sugar content of 79.94 ±â€¯0.57% was isolated from raspberry fruits. A degraded polysaccharide (DRCPI) with sugar content of 83.82 ±â€¯0.71% was obtained from the crude polysaccharides after degradation by Fe2+-H2O2 treatment. The molecular weights of RCPI and DRCPI were determined to be 411,000 and 8010 Da, respectively. GC analysis revealed that both RCPI and DRCPI were composed of the same monosaccharides (rhamnose, arabinose, xylose, mannose, glucose, galactose, and galacturonic acid) in different molar ratios. IR and NMR spectroscopy confirmed that RCPI and DRCPI possessed similar structural characteristics, although DRCPI displayed higher antioxidant activities and greater thermal stability. Furthermore, DRCPI exhibited excellent rheological properties. These data provide evidence to support the application of raspberry-derived polysaccharides in functional foods.

Characterization, antioxidant and hypoglycemic activities of degraded polysaccharides from blackcurrant (Ribes nigrum L.) fruits.

In this study, the degradation of polysaccharides from blackcurrant (BCP) was investigated. Two low-molecular-weight polysaccharides (DBCP-1, DBCP-2) were obtained using Fe2+ with different concentrations of H2O2 solution. IR spectra showed DBCPs had obvious characteristic peaks of polysaccharides. GC analysis confirmed DBCPs were composed of the same monosaccharide units as BCP but with different molar ratios. NMR analysis indicated DBCPs and BCP had similar glycosidic linkage patterns. The surface area of fragmented structure in DBCPs was reduced compared to BCP, and they had no triple helix structure. The results of bioactivity assays indicated that DBCPs exhibited higher antioxidant, α-amylase and α-glucosidase inhibitory activities than BCP, and the degraded polysaccharides with the lower molecular weight possessed higher bioactivities. These results suggested that Fe2+-H2O2 degradation did not change the main structure of polysaccharide and the degree of degradation could play a key role in the bioactivities of the polysaccharides.