Vertical inhibition of the PI3K/Akt/mTOR pathway for the treatment of osteoarthritis

J Cell Biochem. 2013 Feb;114(2):245-9. doi: 10.1002/jcb.24362.


Osteoarthritis is characterized by degenerative alterations of articular cartilage including both the degradation of extracellular matrix and the death of chondrocytes. The PI3K/Akt pathway has been demonstrated to involve in both processes. Inhibition of its downstream target NF-kB reduces the degradation of extracellular matrix via decreased production of matrix metalloproteinases while inhibition of mTOR increased autophagy to reduce chondrocyte death. However, mTOR feedback inhibits the activity of the PI3K/Akt pathway and inhibition of mTOR could result in increased activity of the PI3K/Akt/NF-kB pathway. We proposed that the use of dual inhibitors of PI3K and mTOR could be a promising approach to more efficiently inhibit the PI3K/Akt pathway than rapamycin or PI3K inhibitor alone and produce better treatment outcome.

MeSH terms

  • Autophagy
  • Cell Proliferation / drug effects
  • Extracellular Matrix / drug effects
  • Extracellular Matrix / metabolism
  • Humans
  • Molecular Targeted Therapy
  • NF-kappa B / metabolism
  • Oncogene Protein v-akt* / antagonists & inhibitors
  • Oncogene Protein v-akt* / metabolism
  • Osteoarthritis* / metabolism
  • Osteoarthritis* / pathology
  • Phosphatidylinositol 3-Kinases* / metabolism
  • Phosphoinositide-3 Kinase Inhibitors
  • Signal Transduction
  • Sirolimus / pharmacology
  • TOR Serine-Threonine Kinases* / antagonists & inhibitors
  • TOR Serine-Threonine Kinases* / metabolism


  • NF-kappa B
  • Phosphoinositide-3 Kinase Inhibitors
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • Oncogene Protein v-akt
  • Sirolimus