title: Pentosan polysulfate promotes proliferation and chondrogenic differentiation of adult human bone marrow-derived mesenchymal precursor cells.
abstract: BACKGROUND
  This study was undertaken to determine whether the anti-osteoarthritis drug pentosan polysulfate (PPS) influenced mesenchymal precursor cell (MPC) proliferation and differentiation.
  
  
  METHODS
  Human MPCs were maintained in monolayer, pellet or micromass cultures (MMC) for up to 10 days with PPS at concentrations of 0 to 20 microg/ml. MPC viability and proliferation was assessed using the WST-1 assay and 3H-thymidine incorporation into DNA, while apoptosis was monitored by flow cytometry. Proteoglycan (PG) biosynthesis was determined by 35SO42- incorporation and staining with Alcian blue. Proteoglycan and collagen type I and collagen type II deposition in pellet cultures was also examined by Toluidine blue and immunohistochemical staining, respectively. The production of hyaluronan (HA) by MPCs in MMC was assessed by ELISA. The relative outcome of PPS, HA, heparin or dextran sulfate (DS) on PG synthesis was compared in 5-day MMC. Gene expression of MPCs in 7-day and 10-day MMC was examined using real-time PCR. MPC differentiation was investigated by co-culturing with PPS in osteogenic or adipogenic inductive culture media for 28 days.
  
  
  RESULTS
  Significant MPC proliferation was evident by day 3 at PPS concentrations of 1 to 5 microg/ml (P < 0.01). In the presence of 1 to 10 microg/ml PPS, a 38% reduction in IL-4/IFNgamma-induced MPC apoptosis was observed. In 5-day MMC, 130% stimulation of PG synthesis occurred at 2.5 microg/ml PPS (P < 0.0001), while 5.0 microg/ml PPS achieved maximal stimulation in the 7-day and 10-day cultures (P < 0.05). HA and DS at > or = 5 microg/ml inhibited PG synthesis (P < 0.05) in 5-day MMC. Collagen type II deposition by MMC was significant at > or = 0.5 microg/ml PPS (P < 0.001 to 0.05). In MPC-PPS pellet cultures, more PG, collagen type II but less collagen type I was deposited than in controls. Real-time PCR results were consistent with the protein data. At 5 and 10 microg/ml PPS, MPC osteogenic differentiation was suppressed (P < 0.01).
  
  
  CONCLUSIONS
  This is the first study to demonstrate that PPS promotes MPC proliferation and chondrogenesis, offering new strategies for cartilage regeneration and repair in osteoarthritic joints.
authors.affiliation: Proteobioactives Pty Ltd, 27/9 Powells Road, Brookvale, New South Wales 2100, Australia. peterghosh@proteobioactives.com.au
authors.forename: Peter
authors.initials: P
authors.lastname: Ghosh
authors.forename: Jiehua
authors.initials: J
authors.lastname: Wu
authors.forename: Susan
authors.initials: S
authors.lastname: Shimmon
authors.forename: Andrew Cw
authors.initials: AC
authors.lastname: Zannettino
authors.forename: Stan
authors.initials: S
authors.lastname: Gronthos
authors.forename: Silviu
authors.initials: S
authors.lastname: Itescu
mesh_terms: D000328:Adult; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D002469:Cell Separation; D019902:Chondrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D020219:Chondrogenesis / Q000187:drug effects* / Q000502:physiology; D003094:Collagen / Q000096:biosynthesis; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D015870:Gene Expression; D020869:Gene Expression Profiling; D006801:Humans; D006820:Hyaluronic Acid / Q000096:biosynthesis; D007150:Immunohistochemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D010426:Pentosan Sulfuric Polyester / Q000494:pharmacology*; D011509:Proteoglycans / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000893:Anti-Inflammatory Agents; D011509:Proteoglycans; D010426:Pentosan Sulfuric Polyester; D006820:Hyaluronic Acid; D003094:Collagen