What is cartilage?
Cartilage is a connective tissue found in many parts of the body, including between the joints. It plays an important role in joints by cushioning the bones and protecting them from rubbing against each other. Normally cartilage forms a smooth surface over the end of each articulating bone, but with increasing age cartilage starts to disintegrate first forming pits and then becoming worn away leaving unprotected bone rubbing together. Aging and injury can cause rapid degeneration of the cartilage and also, with age, less cartilage is produced. Loss of cartilage causes osteoarthritis, which is also known as wear and tear of joints with erosion of the bone causing pain, inflammation and loss of movement in the affected joint.
Cartilage is composed of specialised cells called chondrocytes and an extracellular matrix containing a combination of proteins like collagen and elastin, and proteoglycans like chondroitin. Proteoglycans are formed from glycosaminoglycans (GAG) which are a complex carbohydrates combined with protein. GAGs are important components of connective tissue particularly cartilage and tendons as they are part of the extracellular matrix that gives tensile strength to cartilage. They also attract water molecules, which keeps cartilage hydrated and flexible and this helps to maintain its role as the “shock absorbers” of the joints.
Dietary supplements for bones
Glucosamine is a precursor for making glycosaminoglycans (GAG) which are a major component of cartilage, and is naturally produced by the body. Glucosamine and chondroitin are building blocks for the synthesis of cartilage by the body. The production of glucosamine and chondroitin slows down with age and therefore the levels of GAGs are reduced. Dietary supplements containing glucosamine and chondroitin contribute to the synthesis of cartilage, which helps slow down the destruction of articular cartilage and the progression of osteoarthritis and may help relieve symptoms of osteoarthritis.