title: Comparison of glucose derivatives effects on cartilage degradation.
abstract: BACKGROUND
  Glucosamine (GlcN) is a well-recognized candidate for treatment of osteoarthritis. However, it is currently used in derivative forms, such as glucosamine-hydrochloride (GlcN-HCl) or glucosamine sulfate (GlcN-S). However, the molecular mode of action remains unclear. In this study, we compared the effects of Glucose (Glc), Glucuronic acid (GlcA), Glucosamine hydrochloride (GlcN-HCl) and Glucosamine sulfate (GlcN-S) on cartilage degradation.
  
  
  METHODS
  Porcine cartilage explants were co-cultured with recombinant human IL-1beta and each tested substance for 3 days. HA, s-GAG and MMP-2 releases to media were measured using ELISA, dye-binding assay and gelatin zymography, respectively. Similar studies were performed in a human articular chondrocytes (HAC) monolayer culture, where cells were co-treated with IL-1beta and each reagent for 24 hours. Subsequently, cells were harvested and gene expression measured using RT-PCR. All experiments were carried out in triplicate. Student's t-tests were used for statistical analysis.
  
  
  RESULTS
  In cartilage explants treated with IL-1beta, GlcN-S had the highest chondroprotective activity of all four chemicals as shown by the inhibition of HA, s-GAG and MMP-2 released from cartilage. The anabolic (aggrecan core protein; AGG, SOX9) and catabolic (MMP-3, -13) genes in HACs treated with IL-1beta and with/without chemicals were studied using RT-PCR. It was found that, GlcN-HCl and GlcN-S could reduce the expression of both MMP-3 and -13 genes. The IL-1beta induced-MMP-13 gene expression was decreased maximally by GlcN-S, while the reduction of induced-MMP-3 gene expression was greatest with GlcN-HCl. Glc and GlcA reversed the effect of IL-1beta on the expression of AGG and SOX9, but other substances had no effect.
  
  
  CONCLUSIONS
  This study shows that glucosamine derivatives can alter anabolic and catabolic processes in HACs induced by IL-1beta. GlcN-S and GluN-HCl decreased induced MMP-3 and -13 expressions, while Glc and GlcA increased reduced-AGG and SOX9 expression. The chondroprotective study using porcine cartilage explant showed that GlcN-S had the strongest effect.
authors.affiliation: Department of Biochemistry, Chiang Mai University, Chiang Mai 50200, Thailand.
authors.forename: Thanyaluck
authors.initials: T
authors.lastname: Phitak
authors.forename: Peraphan
authors.initials: P
authors.lastname: Pothacharoen
authors.forename: Prachya
authors.initials: P
authors.lastname: Kongtawelert
mesh_terms: D053674:Aggrecans / Q000378:metabolism; D000818:Animals; D002357:Cartilage Diseases / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D002358:Cartilage, Articular / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D018920:Coculture Techniques; D005944:Glucosamine / Q000737:chemistry* / Q000494:pharmacology* / Q000627:therapeutic use; D005947:Glucose / Q000031:analogs & derivatives* / Q000494:pharmacology* / Q000627:therapeutic use; D020723:Glucuronic Acid / Q000494:pharmacology / Q000627:therapeutic use; D006025:Glycosaminoglycans / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000037:antagonists & inhibitors / Q000502:physiology; D053583:Interleukin-1beta / Q000037:antagonists & inhibitors / Q000502:physiology; D010003:Osteoarthritis / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D055758:SOX9 Transcription Factor / Q000378:metabolism; D034421:Sus scrofa
chemical_list: D053674:Aggrecans; D006025:Glycosaminoglycans; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; D020723:Glucuronic Acid; D005947:Glucose; D005944:Glucosamine