Novel strategies have been proposed for articular cartilage damage occurring during osteoarthritis (OA) and -among these- Extracorporeal Shock Wave Therapy (ESWT), intra-articular injections of Platelet-Rich Plasma (PRP) or Hyaluronic Acid (HA) revealed encouraging results.
Thanks to our previous experience on in vitro models of human tendon derived cells, we established here primary cultures of human chondrocytes derived from cartilage explants and measured the in vitro effects of ESW, PRP and HA therapies. After molecular/morphological cell characterization, we assessed those effects on the functional activities of the chondrocyte cell cultures, at the protein and molecular levels.
Our preliminary data suggest that ESWT significantly prevent the progressive dedifferentiation that spontaneously occurs during prolonged chondrocyte culture. We then attested the efficiency of all such treatments to stimulate the expression of markers of chondrogenic potential such as SOX9 and COL2A, to increase the Ki67 proliferation index as well as to antagonize the traditional marker of chondrosenescence p16INK4a (known as Cdkn2a). Furthermore, all our samples showed an ESW- and HA-mediated enhancement of migratory and anti-inflammatory activity onto the cytokine-rich environment characterizing OA.
Taken together, if confirmed, those results suggest a regenerative effect of such therapies on primary human chondrocytes in vitro.
Moreover, we also plan to investigate the ESW treatment effects on the chondrocyte surface expression of major hyaluronan cell receptor CD44, which could enhance the HA benefits in patients affected by OA.
The last step of this project will require an application in vivo of our observations derived from this cell model. In particular, clinical protocols will be studied in order to better define the correct combination of such therapies able to provide novel cues to improve in vivo articular cartilage repair.
