Carboxymethyl chitosan perturbs inflammation profile and colonic microbiota balance in mice

Carboxymethyl chitosan (CMC) is widely used in food and medicine as a biodegradable polymer. However, its effects on inflammation profile and colon health are not well investigated. In the present study, CMC was given to mice to evaluate its possible effects on body weight, blood glucose level, inflammation factors, intestinal permeability and colon microbiota. Results showed that blood glucose level of CMC treated mice was relatively higher than control ones. Glucose tolerance test revealed that CMC treated mice presented higher peak glucose level and lower lag level. CMC treatment increased serum LDL-c level, decreased serum HDL-c and IL-10 level in the fat tissue. Moreover, CMC treatment downregulated the expression of tight junction protein, occludin and ZO-1, in colon as evaluated by Western blot. Colon microbiota analysis demonstrated that CMC treatment significantly decreased the OTUs and relative species abundance. The level of Enterobacteriaceae, Lachnospiraceae and several other bacteria were much higher in the colon content of CMC treated mice. The results collectively suggest that CMC treatment induces disturbance of glucose and fat metabolism, affects the inflammation profile, perturbs colon microbiota balance.