Collagen Defect May Trigger Osteoarthritis
(HealthDayNews, 2/21/05)

As a graduate student at Duke University, Leonidas Alexopoulos, now of M.I.T., examined the relationship between collagen and osteoarthritis, the “wear and tear” form of the disease. Alexopoulos and team studied three groups of mice: one had normal type VI collagen genes; a second had genetically altered genes in which the researchers had eliminated the type VI collagen genes from both parents; and the final group had just one parent whose type VI collagen gene had been removed. After 6 months, the investigators assessed the pericellular matrix (PCM), a narrow tissue surrounding the cartilage on the joint's surface, which along with several types of collagen form a chondron, a structure that seems to buffer these cartilage cells from other cartilage. The researchers found that 73 % of mice with both parents lacking type VI collagen genes exhibited signs of mild to moderate arthritis; whereas, 40 % of those with one parent lacking the gene and only 13 % of those with normal collagen VI production, showed these signs. These findings indicate that low levels of type VI collagen may increase the risk of developing arthritis; however, scientists note that there are numerous types of collagen—a protein found throughout the body in muscle, connective tissue, cartilage and bone—and their exact effects on arthritis will require further investigation.