The Japanese researchers examined the impact of oral supplementation of glucosamine oligomers called chito-oligosaccharides (COS) derived from crab shells in inflammatory bowel disease (IBD) in female mice.
The results, published in the journal Carbohydrate Polymers, suggested COS improved colon length shortening and tissue injury and inhibited inflammation in the colonic mucosa by suppressing the activation of inflammatory cells.
"These data suggest that COS have anti-inflammatory effects in an experimental model of IBD, and could be new functional foods for IBD patients," the researchers wrote.
"The present study suggested that oral administration of COS suppressed loss in body weight, shortened colon length, and increased the colon weight/colon length ratio. Moreover, oral administration of COS prolonged the survival time in this experimental model of IBD," they added.
The term IBD covers ulcerative colitis (UC) and Crohn's disease, characterised by chronic inflammation of the gut. There is thought to have been an increase in people suffering from IBD in recent decades, perhaps due to changes in diet.
The mice were split randomly into four groups of eight. The first group was given tap water and a regular powdered diet, the second 3% dextran sulfate sodium (DSS) in tap water and a powdered diet, the third 3% DSS in tap water and a powdered diet containing 2% COS and the final group was given 3% DSS in water and 2% glucosamine in the diet.
The scientists said the mice given DSS had colons significantly decreased in length compared to the tap water control group. However when comparing the colon length of the DSS group with the COS group, the COS saw colon lengths "suppressed significantly". Conversely there was no difference when they compared that of the DSS and glucosamine groups.
Examining tissue damage
Looking at the changes to tissue that can arise after continued inflammation, the researchers observed erosions, shortening or destruction of crypts (intestinal glands) and severe edema, or tissue build up, in the DSS group.
Meanwhile, in the glucosamine group some erosion was recorded while shortening or destruction of crypts was suppressed and edema was suppressed slightly. The results were most significant, however, in the COS group where shortening and destruction of crypts and edema were, "suppressed markedly".
"These results suggest that oral administration of COS suppresses colon damage in our experimental model of IBD," they wrote.
"Glucosamine also suppressed colon damage in the present study, but its suppressive effect was not as great as that of COS."
Source: Carbohydrate Polymers
"Anti-inflammatory effects of orally administered glucosamine oligomer in an experimental model of inflammatory bowel disease"
Authors: K. Azuma,T. Osaki, S. Kurozumi, M. Kiyose, T. Tsuka, Y. Murahata, T. Imagawa, N. Itoh, S. Minami, K. Sato, Y. Okamoto