Hyaluronic acid sulfate

Only two mucoitin sulfates are well authenticated, one from gastric mucin and one from the cornea (hyaluronic acid sulfate). 

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Chondroitin and chondroitin sulfates (Fig. 21) are found in cartilage, skin, cornea, sclera, and bone. They show high viscosity and water retention and play a role in the connective tissue similar to that of hyaluronic acid. Sulfate groups contribute additional ion-binding capacity. 

Differentiation of hyaluronic acid from the other glycosauninoglycusono-glycans is difficult. This has been responsible in the past for the description of non-existent entities, such as mucoitin sulfate and hyaluronic acid sulfate. 

There are other glycosaminoglycans. Hyaluronic acid [9004-61-9] occurs both free and in noncovalent association with proteoglycan molecules. Heparin [9005-49-6] and heparan sulfate [39403-40-2] also known as heparitin sulfate [9050-30-0] occur in mast cells and in the aorta, Hver, and lungs. 

Highly purified hyaluronic acid, useful in medicine and cosmetic areas, has been prepared from body tissues by different treatments with the help of sodium dodecyl sulfate [199]. 

Proteoglycans linked to chondroitin sulfate by the Xyl-Ser O-glycosidic bond are prominent components of cartilage (see below). The repeating disaccharide is similar to that found in hyaluronic acid, containing... 

As shown in Figure 48-8, the keratan sulfates consist of repeating Gal-GlcNAc disaccharide units containing sulfate attached to the 6 position of GlcNAc or occasionally of Gal. Type 1 is abundant in cornea, and type II is found along with chondroitin sulfate attached to hyaluronic acid in loose connective tissue. Types I and II have different attachments to protein (Figure 48—8). 

Hyaluronic acid may be important in permitting tumor cells to migrate through the EGM. Tumor cells can induce fibroblasts to synthesize greatly increased amounts of this GAG, thereby perhaps facifitating their own spread. Some mmor cells have less heparan sulfate at their surfaces, and this may play a role in the lack of adhesiveness that these cells display. 

The intima of the arterial wall contains hyaluronic acid and chondroitin sulfate, dermatan sulfate, and heparan sulfate proteoglycans. Of these proteoglycans, dermatan sulfate binds plasma low-density lipoproteins. In addition, dermatan sulfate appears to be the major GAG synthesized by arterial smooth muscle cells. Because it is these cells that profiferate in atherosclerotic lesions in arteries, dermatan sulfate may play an important role in development of the atherosclerotic plaque. 

ECM, extracellular matrix HA, hyaluronic acid CS, chondroitin sulfate KS I, keratan sulfate I DS, dermatan sulfate HS, heparan sulfate. 

In various types of arthritis, proteoglycans may act as autoantigens, thus contributing to the pathologic feamres of these conditions. The amount of chondroitin sulfate in cartilage diminishes with age, whereas the amounts of keratan sulfate and hyaluronic acid increase. These changes may contribute to the development of osteoarthritis. Changes in the amounts of cer-... 

The major GAGs are hyaluronic acid, chondroitin 4- and 6-sulfates, keratan sulfates I and II, heparin, heparan sulfate, and dermatan sulfate. 

Chondroitin is quite similar to hyaluronic acid, with the exception that the 4-hydroxyl group of the IV-acetylglycopyranosylamine is now axial instead of equatorial (see formula 13 for hyaluronic acid). This polysaccharide may be sulfated at C-6 of the IV-acetylgalactopyranosylamine, to form chondroitin 6-sulfate. Chondroitin and chondroitin 6-sulfate have... 

Fig. 34.—Circular Dichroism of Glycosaminoglycans (a) Hyaluronic Acid (b) Heparan Sulfate from Normal Mammalian Tissue (c) Chondroitin 4-Sulfate (d) Dermatan Sulfate ...

Fig. 19 Structures of glycosaminoglycans (A) chondroitin-4-sulfate (B) heparin sulfate (C) dermatin sulfate (D) hyaluronic acid (E) chondroitin-6-sulfate (F) keratin sulfate. 

Hyaluronic Add Sulfate.—Meyer and Chaffee108 showed that this mucopolysaccharide of the cornea was a true derivative of hyaluronic acid, since it could be hydrolyzed enzymically by what is now known as hyaluronidase. ... 

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