Methods of inducing chondrogenesis in mesenchymal stem cells using synthetic triterpenoids

Abstract

The present invention relates to methods for enhancing differentiation of mesenchymal stem cells into chondrocytes and/or inducing chondrogenesis. The invention also relates to applications in the treatment of diseases which can affect cartilage (chondrodystrophies). The present invention also relates to methods of treatment comprising establishing a population of chondrocytes from a population of mesenchymal stem cells, which have been induced to differentiate with a synthetic triterpenoid, and administering the population of cells to a patient.

What is claimed is: 
     
         1 . A method of inducing differentiation of a mesenchymal stem cell into a chondrocyte, comprising contacting a mesenchymal stem cell with a sufficient amount of a synthetic triterpenoid to induce chondrogenesis, wherein the synthetic triterpenoid is a compound of the formula: 
       
         
           
           
               
               
           
         
       
       wherein Y is:
 —CN or —C(O)R, wherein R is hydroxy, amino, alkoxy (C≦8) , alkylamino (C≦8) , substituted alkylamino (C≦8) , or heteroaryl (C≦8) ; 
 
       or a pharmaceutically-acceptable salt or tautomer of the formula. 
     
     
         2 . The method of  claim 1 , wherein the mesenchymal stem cell is a bone marrow-derived mesenchymal stem cell. 
     
     
         3 . The method of  claim 1 , wherein the mesenchymal stem cell was isolated prior to contacting with the synthetic triterpenoid. 
     
     
         4 . The method of  claim 1 , wherein R is hydroxy, methoxy, ethyl-amino, or 
       
         
           
           
               
               
           
         
       
     
     
         5 . The method of  claim 4 , wherein the synthetic triterpenoid is CDDO-Im. 
     
     
         6 . The method of  claim 4 , wherein the synthetic triterpenoid is CDDO-EA. 
     
     
         7 . The method of  claim 1 , further comprising contacting the mesenchymal stem cell with a differentiating medium. 
     
     
         8 . The method of  claim 1 , further comprising contacting the mesenchymal stem cell with a co-factor. 
     
     
         9 . The method of  claim 1 , wherein the stem cell is contacted with the synthetic triterpenoid in vitro. 
     
     
         10 . The method of  claim 1 , wherein the stem cell is contacted with the synthetic triterpenoid in vivo. 
     
     
         11 . The method of  claim 1 , wherein the sufficient amount of the synthetic triterpenoid is from 1 nM to 1 μM. 
     
     
         12 . The method of  claim 1 , further comprising incubating the mesenchymal stem cell with a growth factor. 
     
     
         13 . The method of  claim 12 , wherein the growth factor is TGF-β1, TGF-β2, TGF-β1.2, VEGF, insulin-like growth factor I or II, BMP2, BMP4, or BMP7. 
     
     
         14 . The method of  claim 12 , wherein the growth factor is parathyroid hormone, calcitonin, interleukin-6, or interleukin-11. 
     
     
         15 . The method of  claim 1 , further comprising culturing the mesenchymal stem cell before or after contacting it with the synthetic triterpenoid. 
     
     
         16 . The method of  claim 1 , further comprising purifying the mesenchymal stem cell before or after contacting it with the synthetic triterpenoid. 
     
     
         17 . The method of  claim 1 , further comprising implanting the resulting chondrocyte in vivo. 
     
     
         18 . The method of  claim 1 , further comprising implanting the resulting chondrocyte to a patient as part of a treatment for a cartilage-related disease. 
     
     
         19 . The method of  claim 18 , wherein the cartilage-related disease is osteoarthritis, achondrogenesis, chondrodysplasia, SED congenita, Langer-Saldino achondrogenesis, Kniest dysplasia, Stickler syndrome type I, or spondyloepimetaphyseal dysplasia Strudwick type. 
     
     
         20 . The method of  claim 1 , further comprising inducing within the mesenchymal stem cell the expression of a cellular marker associated with chondrogenesis. 
     
     
         21 . The method of  claim 20 , wherein the cellular marker is SOX9, COL2A1, or aggrecan. 
     
     
         22 . The method of  claim 1 , further comprising increasing or up-regulating within the mesenchymal stem cell the level of TGF-β, BMP2, BMP4, SMAD3, SMAD4, SMAD6, SMAD7, TIMP-1 or TIMP-2. 
     
     
         23 . The method of  claim 1 , further comprising decreasing or down-regulating within the mesenchymal stem cell the level of MMP-9.