Connective tissue cartilage

TGF-Ps are pleiotrophic cytokines. They are capable of inhibiting the cell cycle and, hence, cell growth of several cell types, most notably epithelial and haematopoietic cells. These factors, however, stimulate the growth of other cell types, most notably cells that give rise to connective tissue, cartilage and bone. They induce the synthesis of extracellular matrix proteins and modulate the expression of matrix proteases. They also serve as a powerful chemoattractant for monocytes... 

Structure. Collagen is a widespread protein that provides a structural framework of intercellular tissue support in connective tissue, cartilage, bone and other tissues. Elastin is a stretchable support protein. Keratin is the tough protein of fingemails and hair. 

Hyaluronate (4 to 80x10 ) D-Glucosamine D-Glucuronate None Connective tissues, cartilage, synovial uid, vitreous humor, umbilical cord... 

Fibrous proteins, being insoluble in water often have a structural or protective function. The most familiar fibrous proteins are the keratins and collagen. a-Keratin (Figure 25.18) is based on the a-helix secondary structure and is the protein structural component of hair, wool, nails, claws, quills, horns, and the outer layer of skin. P-Keratin is based on the P-sheet secondary structure and occurs in silk as fibroin. L-Cysteine is especially abundant in keratins, where it can account for more than 20% of the amino acids present. Collagen occurs mainly in connective tissue (cartilage and tendons) and has a triple helix structure. 

The internal framework in mammals consists of connective tissue, cartilage and bone. These structures contain and bound the groupings of specialized epithelial cells—which are localized into organs which is turn are integrated to form the complete organism. From a biochemical point of view, the body framework is a network of connective tissue modified in certain regions to form cartilage and bone. 

Close (1934) has classifled the various regions of the body according to water content (a) Extracellular body fluids, plasma, lymph, cerebro-spinal and synovial fluids (b) cellular tissues rich in nuclei, glands, muscles, grey nervous tissue (c) supporting tissues poor in nuclei, connective tissue, cartilage, bone, white nervous tissue. 

Chondroitin Sulfate, along with hyaluronic acid, forms part of the structure of connective tissue. Cartilage has the highest content of chondroitin. Several polysaccharides of this type have been isolated and designated as chondroitin sulfate A, B, and C. The formula shown represents chondroitin sulfate C, which is composed of glucuronic acid and N-acetylgalactosamine 6-sulfate. In type A, the sulfate is bound in the 4-position, while chondroitin sulfate B contains the L-iduronic acid mentioned above. 

Collagen is a rigid, inextensible fibrous protein that is a principal constituent of connective tissue in animals, including tendons, cartilage, bones, teeth, skin, and blood vessels. The high tensile strength of collagen fibers in these struc-... 

Once formed, an acyl CoA is a substrate for further nucleophilic acyl substitution reactions. For example, iV-acetylglucosamine, a component of cartilage and other connective tissues, is synthesized by an aminolysis reaction between... 

The salicylates and nonsteroidal anti-inflammatory drug (NSAIDs) are important in the treatment of arthritic conditions. For example, the salicylates and NSAIDs are used in the treatment of rheumatoid arthritis (a chronic disease characterized by inflammatory changes within the body s connective tissue) and osteoarthritis (a noninflammatory joint disease resulting in degeneration of the articular cartilage and... 

RA is a chronic systemic disease that produces inflammatory changes throughout the connective tissue in the body. It affects joints and other organ systems of the body. Destruction of articular cartilage occurs, affecting joint structure and mobility. RA primarily affects individuals between 20 and 40 years of age. 

Ascorbic acid—vitamin C—is an essential nutrient that the human body cannot manufacture from other compounds. It is needed for the formation of collagen, the protein that makes up connective tissue, and is essential to muscles, bones, cartilage, and blood vessels. It is a strong antioxidant, preventing damage from oxygen free radicals. 

Hyaluronic acid consists of an unbranched chain of repeating disaccharide units containing GlcUA and GlcNAc. Hyaluronic acid is present in bacteria and is widely distributed among various animals and tissues, including synovial fluid, the vitreous body of the eye, cartilage, and loose connective tissues. 

The various cell types are distributed differently within various types of connective tissue fibroblasts often found lying close to collagen fibres, whilst macrophages and mast cells usually appear in clusters around blood vessels. Additionally, whereas fibroblasts are widespread, macrophages are absent from some types of connective tissue, tendons for example. Specialized cells also occur within particular locations for example osteoblasts and osteoclasts (bone), chondrocytes (cartilage), adipocytes (fat tissue) and haemopoietic cells (bone marrow). 

W. A. Horton J. T. Hecht, Chondrodysplasias Disorders ot Cartilage Matrix Proteins. In Connective Tissue and Its Heritable Disorders, P. M. Royce, B. Steinmann, Eds. Wiley-Liss New York, 2002 pp 909-937. 

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