Like the other glycosaminoglycans, chondroitin sulfates are negatively charged and highly hydrated. They attract positively charged sodium ions, which in turn induce water influx. Finally, chondroitin sulfate helps draw fluid into the proteoglycans and thus into the extracellular matrix (extracellular matrix, intercellular substance, ECM, ECM) of articular cartilage and synovium (synovial fluid). Chondroitin sulfate is the glycosaminoglycan with the highest water binding capacity.The intercellular substance of mature cartilage contains up to 75% water in addition to the main components collagen and proteoglycans. The water-binding capacity of the proteoglycans is essential for the formation of the viscous, firm material of the cartilage tissue, which is elastic in both compression and flexion. The ability to bind water maintains the internal tension of cartilage, which is the basis for cartilage’s mechanical properties, such as smooth motion, elasticity, and shock absorption.
Finally, chondroitin sulfates A, B as well as C, as components of proteoglycans, are important in maintaining cartilage function and health. This applies in particular to the cartilage tissue of joints and intervertebral discs. In addition to water, the intervertebral discs consist of collagenous connective tissue fibers and fibrocartilage. Chondroitin sulfate can promote the function of intervertebral discs and help prevent their degeneration.
CS protects existing cartilage from premature wear by inhibiting the activity of certain cartilage catabolic enzymes. Chondroitin sulfate inhibits the activity of collagenase and elastase, preventing the degradation of collagens (structural proteins of connective tissue) in the cartilage matrix. The collagen network is required for the internal binding of connective tissue and cartilage substance.
Chondroitin sulfate and osteoarthritis
Deficiency of chondroitin sulfate and other glycosaminoglycans leads to increased degradation of proteoglycans, collagens, and chondrocytes-cells derived from chondroblasts and resident in cartilage tissue-due to increased activity of catabolic enzymes. The result is a reduction in cartilage substance, which increases frictional resistance as well as abrasion and increases the risk of developing osteoarthritis.
In old age, the risk of osteoarthritis is particularly high. The ability to synthesize chondroitin sulfate itself diminishes. As a result, the body does not produce enough proteoglycans and collagen to keep cartilage healthy. In addition, the activity of cartilage-degrading enzymes can no longer be inhibited and increased catabolism of cartilage mass occurs. In old age, therefore, the additional supply of chondroitin sulfate plays an essential role.
Chondroitin sulfate, like glucosamine sulfate, is counted among the chondroprotectants (cartilage-protecting substances) used in degenerative joint diseases. They also belong to the SYSADOA (Symptomatic Slow Acting Drugs in Osteoarthritis) and are characterized by a lack of direct analgesic effect. Chondroitin sulfate and glucosamine sulfate act synergistically, i.e. in the same sense. They stimulate the formation of new cartilage while inhibiting the activity of cartilage-destroying enzymes. With the use of chondroprotectants, the regeneration of cartilage tissue can be promoted in osteoarthritis patients, further loss of cartilage mass can be prevented, and thus the disease process of osteoarthritis can be stopped.
Furthermore, they are believed to have anti-inflammatory (anti-inflammatory) properties. Several scientific studies show that chondroitin sulfate leads to the decrease of pain, swelling and improved joint function and mobility.
Because chondroitin sulfate is poorly absorbed when taken orally, osteoarthritis patients should take glucosamine sulfate, which is converted to chondroitin sulfate in the body, for treatment.