The intracellular pathway of cartilage proteoglycan biosynthesis was investigated in isolated chondrocytes using a protein A-gold electron microscopy immunolocalization procedure. Proteoglycans contain a protein core to which chondroitin sulfate and keratan sulfate chains and oligosaccharides are added in posttranslational processing. Specific antibodies have been used in this study to determin...

Sulfated mucopolysaccharides, such as heparin, heparan sulfate, chondroitin sulfates and dermatan sulfate, have been shown to be normal constituents of animal tissues and body fluids. Their biological functions are not yet known with certainty. A role as lubricants in the living organism was ascribed to these sulfated mucopolysaccharides due to their highly viscous and elastic properties in sol...

Mouse chondrocytes were allowed to differentiate from 11-day dissociated limb-bud mesenchymal cells cultured at high density. Over a period of 5 days in culture these cells differentiated from a culture containing a population of mesenchymal cells and myoblasts into one containing cartilage nodules. Chondrogenesis, as demonstrated by the sulfated proteoglycans (PGS) synthesized, was monitored q...

Osteoarthritis (OA) is a leading cause of disability in the United States. Current treatment focuses on symptom relief and improving a patient's overall function. Pharmacological treatments aim to correct symptomatic complaints as well as structural problems in OA. Glucosamine (sulfate or hydrochloride) and chondroitin sulfate have been linked as an optional treatment in OA for several years. T...

The glycosaminoglycan chondroitin sulfate is essential in human health and disease but exactly how sulfation dictates its 3D-structure at the atomic level is unclear. To address this, we have purified homogenous oligosaccharides of unsulfated chondroitin (with and without (15)N-enrichment) and analysed them by high-field NMR to make a comparison published chondroitin sulfate and hyaluronan 3D-s...

After tissue injury, fibroblast migration from the peri-wound collagenous stroma into the fibrin-laden wound is critical for granulation tissue formation and subsequent healing. Recently we found that fibroblast transmigration from a collagen matrix into a fibrin matrix required the presence of fibronectin. Several integrins-alpha 4 beta 1, alpha 5 beta 1, and alpha v beta 3-with known fibronec...

We have examined the effects of beta-xylosides, which act as exogenous acceptors for glycosaminoglycan chain initiation, on the morphology and proteoglycan biosynthesis of PC12 pheochromocytoma cells, and on monolayer, aggregate and explant cultures of early postnatal rat cerebellum. PC12 cells cultured for 13 days in the presence of nerve growth factor (NGF) and beta-xyloside, and labeled duri...

Microsomal preparations from chondroitin 6-sulfate-producing chick embryo epiphyseal cartilage, and from chondroitin 4-sulfate-producing mouse mastocytoma cells, were incubated with UDP-[14C]glucuronic acid and UDP-N-acetylgalactosamine to form non-sulfated proteo[14C]chondroitin. Aliquots of the incubations were then incubated with 3'-phosphoadenylylphosphosulfate (PAPS) in the presence or abs...