Glucosamine sulfate modulates dysregulated activities of human osteoarthritic chondrocytes in vitro

Osteoarthritis Cartilage. 2000 May;8(3):207-12. doi: 10.1053/joca.1999.0291.

Abstract

Objective: The efficacy of glucosamine sulfate (GS) in the symptomatic treatment of patients with osteoarthritis (OA) is suggested to be mediated by still unknown effects on the altered OA cartilage.

Design: Using human OA chondrocytes in culture, the effects of GS on protein synthesis, caseinase, collagenase, phospholipase A2 (PLA2) and protein kinase C (PKC) activities as well as production of nitric oxide and cyclic AMP were studied in both cells and culture medium.

Results: GS significantly reduced PLA2 activity, and more modestly collagenase activity, in the OA chondrocytes in a dose-dependent manner. By contrast, PLA2 and collagenase activity of the culture medium was not modified. No effects on caseinase activity was seen. GS significantly and dose-dependently increased protein synthesis. GS did not modify nitric oxide and cAMP production but significantly increased PKC production.

Conclusion: GS modified cultured OA chondrocyte metabolism by acting on PKC, cellular PLA2, protein synthesis and possibly collagenase activation. Extrapolation of the effect to the in-vivo situation remains hypothetical but they might represent some possible mechanisms of action of the drug in human.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caseins / drug effects
  • Cells, Cultured
  • Chondrocytes / drug effects*
  • Collagenases / drug effects
  • Culture Media
  • Cyclic AMP / metabolism
  • Dose-Response Relationship, Drug
  • Glucosamine / pharmacology*
  • Humans
  • Nitric Oxide / metabolism
  • Osteoarthritis / metabolism*
  • Phospholipases A / drug effects
  • Phospholipases A2
  • Protein Biosynthesis
  • Protein Kinase C / drug effects

Substances

  • Caseins
  • Culture Media
  • Nitric Oxide
  • Cyclic AMP
  • Protein Kinase C
  • Phospholipases A
  • Phospholipases A2
  • Collagenases
  • Glucosamine