Preventive actions of a high dose of glucosamine on adjuvant arthritis in rats.
OBJECTIVE
Glucosamine, a naturally occurring amino monosaccharide has been used to treat or prevent osteoarthritis in humans. In this study, we evaluated the effect of glucosamine on rat adjuvant arthritis, a model of rheumatoid arthritis.


METHODS
Adjuvant arthritis was induced in male Wistar rats by injection of Freund's complete adjuvant (FCA) into the right hind paw, and 300 mg/kg of glucosamine, an extra-dose compared with a regular dose for osteoarthritis patients (1.5 g/day, approximately 25 mg/kg), was orally administered once a day to the arthritic rats for 22 days.


RESULTS
Glucosamine significantly suppressed the increase in arthritis score (p < 0.05) after day 10 of adjuvant injection, and inhibited the swelling of FCA-injected right and -uninjected left hind paws (p < 0.01) after day 18. In addition, histopathological examination of the arthritic joints revealed that glucosamine suppressed synovial hyperplasia, cartilage destruction and inflammatory cell infiltration. Furthermore, glucosamine reduced the production of nitric oxide and prostaglandin E(2) in plasma (p < 0.05).


CONCLUSIONS
These observations suggest that glucosamine is able to suppress the progression of adjuvant arthritis in rats. Glucosamine may be expected as a novel anti-inflammatory agent for treatment of rheumatoid arthritis.
Hua
J
J
Department of Host Defense and Biochemical Research, School of Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
Suguro
S
S
Hirano
S
S
Sakamoto
K
K
Nagaoka
I
I
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D001169:Arthritis, Experimental / Q000517:prevention & control*; D001172:Arthritis, Rheumatoid / Q000517:prevention & control*; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005620:Freund's Adjuvant / Q000494:pharmacology; D005944:Glucosamine / Q000378:metabolism / Q000494:pharmacology*; D007249:Inflammation; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013583:Synovial Membrane / Q000378:metabolism; D013997:Time Factors
D000893:Anti-Inflammatory Agents; D009569:Nitric Oxide; D005620:Freund's Adjuvant; D015232:Dinoprostone; D005944:Glucosamine