Lysosomal Glycosidases in Degradation of Human Articular Cartilage

Joint diseases cause serious medical problems for several million people world-wide and therefore the World Health Organization has designated years 2000-2010 as the Decade of the Bone and Joint (Popko et al.2011). Osteoarthritis (OA) is the most common, and increasingly prevalent, human joint disorder (Dieppe, 2000). It has been estimated that in 1990 12 % of Americans, nearly 21 million people had clinical symptoms of osteoarthritis (Lawrence et al., 1998). Rheumatoid arthritis (RA) affects about 0.3 to 1.5% of the world population(Chikanza et.al., 1998). Juvenile idiopatic arthritis (JIA) is one of the most common rheumatic diseases in children, which causes pain and functional disability. According to a 2008 study performed by the National Arthritis Data Workgroup, there were close to 3000,000 children in the U.S.A. with some form of juvenile arthritis (Giannini et al., 2010). Lyme arthritis (LA) caused by spirochete Borrelia burgdorferi, is increasing in prevalence disease involving the musculoskeletal system, particularly affecting knee joints (Pancewicz et. al.2009). RA and JIA are chronic autoimmune inflammatory diseases primarily affecting the synovial membrane, leading to joint damage and destruction. OA is the most common joint disorder and a major public health problem in western populations (Lawrence et al. 1998). Clinical and epidemiological studies on OA have recognized a series of etiologic factors including local factors (such as malformations or joint injuries) and systemic factors (such as overweight, race, gender, or metabolic diseases). OA is associated with a loss of proper balance between synthesis and degradation of the macromolecules that gives articular cartilage its biomechanical and functional properties. Concomitantly in OA, changes occur in the structure and metabolism of the synovium and subchondral bone of the joint.