Thirty million Americans suffer from osteoarthritis, a disease that causes debilitating joint pain. Salk scientists have discovered a potential new therapy that could reverse the disease.
The research, out in the peer-reviewed journal Protein & Cell, is all about cartilage, said Salk scientist and co-first author Paloma Martinez-Redondo.
“(Cartilage) acts as a cushion between the two bones," Martinez-Redondo said. "So, when we have to move any joint, in this case the knee, we’d have a cushion here that would prevent the erosion between the two bones.”
Osteoarthritis causes cartilage in joints to thin out, which leads to painful bone-on-bone contact. Over time, it’s harder for our bodies to repair that cartilage, due to issues like aging. So, Martinez-Redondo and her partner investigated whether two proteins — alpha-KLOTHO and TGF beta receptor 2 — associated with reducing aging and with cartilage production could help.
These proteins are naturally produced in the body. Instead of trying them out individually, the scientists combined the proteins and tested the combined protein therapy in rats and in human cells.
“We have previous studies showing these two proteins could help us ... not only to prevent the pathology but also to improve the repair," Martinez-Redondo said. "But it was also lucky, because we tried putting them together and they worked better together.”
In animal models, scientists saw cartilage grow back, reversing the effects of osteoarthritis. It also showed signs of stopping the disease from coming back.
“From the very first time we tested this drug combination on just a few animals, we saw a huge improvement,” said Isabel Guillen-Guillen, also a Salk scientist and the paper’s co-first author. “We kept checking more animals and seeing the same encouraging results.”
And when scientists tested out the proteins in human cartilage cells, there were also promising results.
“That’s not the same as showing how these drugs affect the knee joint in humans, but we think it’s a good sign that this could potentially work for patients,” Martinez-Redondo said.
Martinez-Redondo said currently patients can get access to therapies that only either relieve or are intrusive, involving cell or even entire joint replacement.
She said this type of therapy aims to reverse the disease naturally. Now, these scientists plan on taking the results to human clinical trial.