Hyaluronan Function in OA
Osteoarthritis, the most common type of arthritis, causes pain, disability and decreased quality of life for over 20 million people in the United States alone. Osteoarthritis (OA) results from damage and degeneration of joint cartilage. Maintenance of healthy joints depends on preserving the normal balance of cartilage breakdown and replacement. Disruption of this balance leads to cartilage loss and osteoarthritis.
Hyaluronan is a very large molecule made by cartilage cells and is known for its ability to interact with proteins found in joint tissues. It has been thought to primarily function as a structural component of the matrix which surrounds cartilage. Recent studies, including Dr. Li’s, suggest that hyaluronan may function as a signaling molecule, influencing the behavior of the cartilage cells and enhancing their ability to maintain healthy cartilage.
Dr. Li uses a genetic approach to remove hyaluronan from the developing articular cartilage of mice. Her studies show that loss of hyaluronan during embryonic development prevents the formation normal joint cartilage, demonstrating for the first time a genetic requirement for hyaluronan in joint cartilage development. These exciting observations suggest that 1) hyaluronan may also be required for maintenance of healthy articular cartilage in adults, and 2) that loss of hyaluronan during adulthood may lead to the onset of osteoarthritis.
In this project, Dr. Li will directly test these hypotheses. There is no cure for osteoarthritis, and little is known about the genetic causes of this disabling disease. This study will provide insight into new targets for future therapies by identifying hyaluronan as a required genetic signal necessary for osteoarthritis prevention, and by clarifying its role in maintaining cartilage health.