Purification and characterization of turanose, a sucrose isomer and its anti-inflammatory effects in dextran sulfate sodium (DSS)-induced colitis model

The prevalence of inflammatory bowel disease (IBD) is increasing worldwide, and the key risk factor is high sugar diet. The objective of this study was to investigate anti-inflammatory effects of turanose on IBD in a dextran sulfate sodium (DSS)-induced colitis mouse model. An amylosucrase from Neisseria sicca (NsiAS) was newly identified and successfully expressed. This enzyme exhibited optimal activity at 45 °C and pH 8.5. By utilizing this recombinant enzyme expressed in the E. coli host, turanose yield maximally reached 47% from 2.0 M sucrose. Colitis was induced with two 5-d cycles of 2.5% DSS in drinking water with a 10-d inter-cycle interval. Mice were fed AIN93G diet with 25% and 50% turanose replacement. Improved disease activity index scores, colon length, histopathological features, and myeloperoxidase activity were observed in the turanose supplemented group. Meanwhile, decreases in micro RNA (miR)-21 expression, histone acetylation, expression of pro-inflammatory cytokines, and phosphorylated ERK and STAT3 were observed in colon tissues. Notably, miR-21 and histone acetylation levels were found to positively correlated with expression of tumor necrosis factor α. In conclusion, turanose can attenuate colitis via regulatory effects on miRNA-21 expression and histone acetylation-related proinflammatory mediators. These findings also support further exploration of turanose as a potential therapeutic sugar substitute for patients with IBD.