Chondroitin sulfate is not digested at all in the mouse small intestine but may suppress interleukin 6 expression induced by tumor necrosis factor-a

Salmon nasal cartilage proteoglycan (PG) was orally administered to mice. The PG digest was recovered from the small intestine, and its sugar chain size and unsaturated disaccharide content were examined. The elution position of the PG digest following Sepharose CL-4B chromatography was consistent with that of actinase-digested PG prior to administration. The PG digest was incubated with chondroitinase ABC, which resulted in the elution pattern of the unsaturated disaccharides being identical to that of the degraded product of actinase-digested PG. The core protein of PG was digested in the mouse small in-testine, but chondroitin sulfate, which is the sugar chain of PG, was not degraded at all. Then, the effects of chondroitin 4-and 6-sulfates on human colon cancer cells were examined. These chondroitin sulfates were found to suppress the expression of interleukin-6 induced by TNF-a. Overall, the chondroitin sulfate chain may act on the intestinal epithelium and suppress inflammation of the intestinal tract.(c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Salmon nasal cartilage proteoglycan (PG) was orally administered to mice, and its effects on the small intestine were examined. The PG digest recovered from the intestine showed consistent properties with the actinase-digested PG prior to administration. Chondroitin sulfate, a sugar chain of PG, was found to be resistant to digestion in the mouse small intestine, and chondroitin sulfates showed a suppressive effect on colon cancer cells.