A disease of the joints, osteoarthritis affects more than 30 million adults and is the fifth-leading cause of disability in the United States. In a new study, scientists have discovered the cellular pathway that leads to osteoarthritis and have identified a commonly used anti-depressant (paroxetine) that inhibits this pathway. The team found that paroxetine not only slows down cartilage degeneration, but also promotes cartilage health in both mice and human cartilage in vitro. The drug may be the first-ever treatment for this debilitating, degenerative disease. “Osteoarthritis destroys joint cartilage and results in pain and disability,” said Fadia Kamal, PhD, Assistant Professor of Orthopedics and Rehabilitation at Penn State College of Medicine. “Patients live with this pain until their cartilage is extremely degenerated. Unfortunately, an invasive artificial joint replacement surgery is the only treatment orthopedists are currently able to offer. There has been a dire need to identify novel therapeutic targets, [and] approaches or agents that can actively halt or reverse the osteoarthritis disease process.” In previous research, Dr. Kamal and her colleagues found that increased production and activity of a particular enzyme, G protein-coupled receptor kinase 2 (GRK2), led to harmful cell growth in heart and kidney disease. Dr. Kamal, who holds doctorate degrees in cell physiology and pharmacy, explained that osteoarthritis is similarly driven by uncontrolled growth of cartilage cells, a process called chondrocyte hypertrophy, but how this proliferation occurs had been a mystery. Given their knowledge of the role of GRK2 in heart and kidney disease, Dr. Kamal and her team decided to investigate the enzyme in osteoarthritis patients.Login Or Register To Read Full Story