Format

Send to

Choose Destination
See comment in PubMed Commons below
Osteoarthritis Cartilage. 2007 Jun;15(6):646-55. Epub 2007 Mar 6.

Glucosamine promotes chondrogenic phenotype in both chondrocytes and mesenchymal stem cells and inhibits MMP-13 expression and matrix degradation.

Author information

1
Cartilage Biology and Orthopaedics Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA.

Abstract

OBJECTIVES:

Glucosamine (GlcN), a natural amino monosaccharide, is a constituent of glycosaminoglycans (GAGs) found in hyaline cartilage. GlcN salts constitute a new class of nutraceutical components with putative chondroprotective activity, which may target chondrocytes as well as chondroprogenitors cells, such as mesenchymal stem cells (MSCs), during cartilage turnover and repair. In the present study, we examined the effects of GlcN on chondrogenesis of human MSCs (hMSCs) and the phenotype of normal and osteoarthritic human articular chondrocytes, using an in vitro pellet culture model maintained in a defined medium.

METHODS:

hMSCs and normal and osteoarthritic human chondrocytes grown as pellet cultures, stimulated or not with interleukin-1beta (IL-1beta), were treated with varying doses of GlcN. Expression of cartilage matrix genes and cartilage degrading enzymes was determined by semiquantitative and quantitative real-time reverse transcription polymerase chain reaction (RT-PCR), and by histological staining of cartilage markers, as well as sulfated GAG (sGAG) analysis and Western blotting.

RESULTS:

Chondrocytes grown in the presence of serum for 11 days showed decreased expression of the cartilage matrix genes, collagen type II (collagen II) and aggrecan, as early as day 3, which was reversed with GlcN treatment by day 11. Both hMSCs and chondrocytes grown as pellet cultures in defined medium and treated with 100 microM GlcN exhibited enhanced expression of collagen II and aggrecan as well as increased content of sGAG, when compared to control untreated pellets. However, high doses of GlcN (10-20mM) were inhibitory. GlcN treatment partially blocked IL-1beta mediated downregulation of collagen II and aggrecan expression and inhibited expression of the matrix degrading enzyme, matrix metalloproteinase 13 (MMP-13), in both chondrocytes and hMSCs undergoing chondrogenesis.

CONCLUSIONS:

These observations suggest that GlcN treatment enhances hMSC chondrogenesis and maintains cartilage matrix gene expression in chondrocytes, which may account for some of the reported chondroprotective properties of GlcN on cartilage.

PMID:
17337215
DOI:
10.1016/j.joca.2007.01.014
[Indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center