Effects of glucosamine sulfate on intracellular UDP-hexosamine and UDP-glucuronic acid levels in bovine primary chondrocytes.
2007 (English)In: Osteoarthritis and Cartilage, ISSN 1063-4584, E-ISSN 1522-9653, Vol. 15, no 7, 773-779 p., 17320421Article in journal (Refereed) Published
OBJECTIVE: To analyze the effects of exogenously added glucose (Glc), glucosamine (GlcN) and glucosamine sulfate (GS) on the intracellular UDP-hexoses (UDP-Hex), UDP-N-acetylhexosamines (UDP-HexN) and UDP-glucuronic acid (UDP-GlcA) levels in bovine primary chondrocytes.
METHODS: Chondrocytes were incubated with different concentrations of Glc, GlcN and GS either in high- or low-glucose DMEM for up to 120min to analyze the intracellular levels of UDP-Hex, UDP-GlcA and UDP-HexN by a reversed-phase high-performance liquid chromatography-electrospray ionization mass spectrometry analysis. Glycosaminoglycan (GAG) synthesis rate and aggrecan mRNA expression levels were quantified using (35)S-sulfate incorporation assay and quantitative real-time RT-PCR, respectively. The cells were cultivated for 2 days or 8 days before UDP-sugar analysis.
RESULTS: Levels of UDP-HexN and UDP-GlcA were unchanged at 10microM concentration of GS in low-glucose DMEM, while addition of 1mM GlcN or GS in low-glucose DMEM for 10min increased UDP-HexN level. The highest intracellular level of UDP-HexN was reached at 30min after addition of 1mM GS to the cells. The intracellular contents of UDP-HexN and UDP-GlcA related to UDP-Hex were higher after prolonged cultivation of chondrocytes for 8 days compared with 2-day-old cultures. Aggrecan mRNA expression and GAG synthesis remained at control level after the cells were treated with 10, 100microM or 1mM of GS for 24h.
CONCLUSION: Physiologically relevant level of GS could not increase the intracellular UDP-HexN and UDP-GlcA levels in bovine primary chondrocyte, while longer-time culture itself appeared to increase the intracellular UDP-HexN and UDP-GlcA levels.
Place, publisher, year, edition, pages
Saunders Elsevier, 2007. Vol. 15, no 7, 773-779 p., 17320421
Chondrocyte, glucosamine sulphate, UDP-sugar, proteoglycan, osteoarthritis
Cell and Molecular Biology Medicinal Chemistry Orthopedics Biochemistry and Molecular Biology
Research subject Biochemistry; cellforskning; Orthopaedics
IdentifiersURN: urn:nbn:se:umu:diva-106637DOI: 10.1016/j.joca.2007.01.010PubMedID: 17320421OAI: oai:DiVA.org:umu-106637DiVA: diva2:843100