Excessive Glucose and Fructose Intake Aggravates the Pathogenesis of Rat Experimental Colitis

Ulcerative colitis (UC) is a relapsing and remitting disease that causes chronic inflammation and ulceration of colonic tissue, especially in the rectum region. Although sugars are rapidly digested and absorbed and can be efficiently utilized as energy in the body, they are also known to promote inflammation. Herein, we aimed to examine the effects of special diets containing excess glucose (Glu) or fructose (Fru) on the pathogenesis of dextran sulfate sodium (DSS)-induced UC in Wistar rats. The model rats (termed UC rats or UCR) were divided into three groups: DSS group, UCR fed a regular diet; DSS + Glu group, UCR fed a special diet mixed with glucose at 63% calories; DSS + Fru group, UCR fed a special diet mixed with fructose at 63% calories. The DSS + Glu and DSS + Fru groups exhibited a lower weight and colon length than the DSS group. The DSS + Fru group had a lower diet and DSS intake than the other two groups. The microscopic findings revealed that the DSS + Glu and DSS + Fru groups tended to have higher severity scores than the DSS group. The DSS + Fru group tended to have higher serum and colonic tissue concentrations of inflammatory cytokines than the DSS + Glu group. Collectively, these findings suggest that excessive glucose and fructose intake can aggravate intestinal inflammation.