Effects of glucosamine hydrochloride on the production of prostaglandin E2, nitric oxide and metalloproteases by chondrocytes and synoviocytes in osteoarthritis.
OBJECTIVES: To determine the response of glucosamine hydrochloride on chondrocytes and synoviocytes in terms of prostaglandin E2 (PGE2), nitric oxide (NO) and matrix metalloproteases (MMPs). METHODS: Chondrocytes and synoviocytes were prepared from joint specimens of patients who underwent total knee arthroplasty for osteoarthritis (OA). Chondrocytes from patients with femoral neck fracture were served as a normal control. Culture cells were stimulated by 5 ng/ml of IL-1beta and treated with various concentration of glucosamine hydrochloride (from 1 microg/ml to 500 microg/ml). PGE2, NO, MMP-1, MMP-3, and MMP-13 levels were evaluated in the culture supernatant. Further, the expression of COX-2 mRNA was studied by semiquantitative PCR. RESULTS: With IL-1beta stimulation, the levels of these mediators increased dramatically, except for NO from synoviocytes. After stimulation, levels of these mediators in OA chondrocytes were higher than synoviocytes and normal chondrocytes, and the level of MMP-3 was higher than those of MMP-1 and MMP-13. Glucosamine hydrochloride at a concentration of 100 microg/ml suppressed PGE2 production, and partly suppressed NO production. It also suppressed the production of MMPs from normal chondrocytes and synoviocytes but not from OA chondrocytes. CONCLUSION: Glucosamine modulates the metabolism of chondrocytes and synoviocytes and its mode of action differs between cells and conditions.