How to get stem cells to repair damaged cartilage
Osteoarthritis – the most common type of arthritis is a degenerative joint disease that develops as a result of injuries or physical wear of joints in elderly people. The result of the inflammatory process in osteoarthritis is the thinning of cartilage covering the articular surfaces and acting as shock absorbers for the skeleton. This is manifested by difficulties in flexing the joints and pain.
A group of researchers working under the leadership of Peter G. Schultz from the Scripps Research Institute screened 22,000 compounds that make up cartilage tissue and identified one – cartogenin – inducing the acquisition of chondrocyte characteristics by mesenchymal stem cells (adult stem cells capable of differentiating into connective tissue cells). This molecule activated the genes responsible for the synthesis of cartilage tissue components: aggrecan and type II collagen.
Experiments on mice with simulated osteoarthritis have shown that cartogenin injections reduce the concentration of oligomeric matrix protein of cartilage. In the joints of people with osteoarthritis, an excess of this protein is usually detected, the level of which is considered an indicator of the severity of the disease. Cartogenin therapy for 42 days restored the animals' ability to transfer weight to the diseased joint.
During laboratory experiments, it was found that cartogenin suppresses the activity in mesenchymal stem cells of a protein known as filamin A. This leads to the release of other compounds that regulate the activity of genes in such a way that cells turn into functional chondrocytes. Apparently, in the conditions of the body, this protects the cartilage tissue from damage and promotes its recovery.
The researchers hope that the mechanism they discovered will help millions of people who develop osteoarthritis in old age. Given the current trend towards the aging of the population, this discovery is of great importance.
Article by Kristen Johnson et al. A Stem Cell–Based Approach to Cartage Repair is published in the preliminary on-line version of the journal Science.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of ScienceNews: Stem cell treatment spurs cartilage growth.
06.04.2012