Kollagenet

Kollagenet is a family of structurally related proteins that form the main component of connective tissues in animals. It provides tensile strength and structural support in tendons, bones, skin, cartilage, blood vessels, and organs. Kollagen proteins are produced by a wide range of cells, including fibroblasts, chondrocytes, and osteoblasts, and are secreted into the extracellular matrix where they assemble into fibrils and networks.

Most kollagen types share a common triple-helix structure formed by three polypeptide chains rich in glycine, proline, and hydroxyproline. The collagen gene family is large, with several major types serving different tissue roles. Type I collagen is the most abundant in the body and predominates in skin, bone, and tendon; type II is prominent in cartilage; type III occurs in reticular fibers of skin and blood vessels; type IV forms the basement membrane. Post-translational modifications and cross-linking by lysyl oxidase help stabilize collagen fibrils.

Biosynthesis begins with the production of procollagen inside cells, followed by secretion, extracellular processing of propeptides, and assembly into mature fibrils. This process is dependent on vitamin C, and disruptions can lead to weakened collagen networks. Disorders affecting kollagen synthesis or structure include conditions such as Ehlers-Danlos syndrome and osteogenesis imperfecta, while aging is associated with gradual collagen degradation and reduced tissue elasticity.

Dietary kollagen and collagen-derived supplements are marketed for joint and skin health, though evidence on their efficacy varies. Kollagen-based materials are also used in medical and dental applications, as scaffolds for tissue engineering and wound healing.