Seafood, red meat and other zinc-rich food may increase a person's risk of arthritis, new research suggests.
The Korean study found that the cartilage can be destroyed by molecular changes involved in processing zinc - a naturally-occurring metallic element. When the cartilage breaks down in osteoarthritis, the bones rub together, resulting in swelling and stiffness.
Osteoarthritis typically affects the joints and is the most common type of arthritis, with some 1 million people visiting their doctor each year in search of relief from the condition.
According to the researchers, the results came somewhat as a surprise.
"No evidence available to date clearly indicated that zinc plays a causal role in osteoarthritis," Jang Soo Chun of the Gwangju Institute of Science and Technology in Korea said in a statement.
Chun confirmed that their study revealed the entire series of molecular events in the osteoarthritis zinc pathway, from zinc influx into cells to cartilage destruction. They examined cartilage from osteoarthritis patients as well as a mouse model of the disease. In doing so, they discovered abnormally high levels of a protein called ZIP8, which is found in the plasma membrane of cartilage cells.
"Our findings suggest that local depletion of zinc or pharmacological inhibition of ZIP8 function in cartilage tissue would be effective therapeutic approaches for the treatment of osteoarthritis," Chun said. "We are hopeful that this research will lead to the discovery and rapid development of novel drugs to suppress the progression of this debilitating disease."
