Published online 4 April 2012
In China, osteoporosis is a disease that has reached epidemic proportions. Treatment using bone-growth stimulating hormones is limited to a two-year period because longer usage may lead to increased bone resorption. This prevalence places a dire need for more effective treatment.
Lingqiang Zhang at the Beijing Institute of Radiation Medicine, Ge Zhang and Ling Qin at the Chinese University of Hong Kong and co-workers have now developed a gene therapy for osteoporosis. The treatment uses small interfering RNAs (siRNAs) that are designed to target the gene Plekho1 in bone-forming cells.
Previous studies have shown that Plekho1 inhibits bone formation, so knocking down Plekho1 should increase bone formation. The RNA is delivered only to bone-forming cells through a specific amino acid sequence embedded in the delivery system.
The unique delivery system successfully inhibited Plekho1 in bone-forming cells for both normal mice and mice suffering from osteoporosis. Within nine weeks, the treatment helped build bone mass and increase bone density, thus effectively reversing osteoporosis. This novel delivery system could be used to transport other therapies that treat bone and muscle diseases.