Hyaluronic acid polymerization

Polymeric carbohydrates are usually encountered as distributions, so high resolution is rarely important. Of all biological macromolecules, carbohydrates are particularly amenable to analysis by GPC because hydrophobic interactions are typically weak. A section below is devoted to the analyses of carboxymethylcellulose and xanthan. Other examples of polysaccharides of interest are hyaluronic acid,62 polymers of (l-glucose,121125 heparin,126127 cellulose and chitin,128 and Mucorales extracellular polysaccharides.129... 

The maintenance of the normal, anomalous viscosity index of synovial fluid is essential for its proper function as a lubricant between joint surfaces. The concentration and the degree of polymerization of hyaluronic acid in synovial fluids of patients with rheumatoid arthritis and other degenerative joint diseases have been the subjects of widespread investigation. Ragan and Meyer (R1) ascribed the changes in synovial fluid in... 

The lower degree of polymerization of hyaluronic acid present in rheumatoid fluids (B3, BIO, B13, B18) undoubtedly impairs the effectiveness of the fluid as a lubricant between joints. Another factor contributing to this may be the lower concentration of hyaluronic acid found in certain rheumatoid effusions. Special viscosity and elastic properties are exhibited by hyaluronic acid in synovial fluid in concentrations in excess of 0.2 g/lOO ml (Bll) the concentration of hyaluronic acid in inflamed joint fluids of rheumatoid arthritis is generally less than this value. In a recent investigation, Hamerman and Sandson (H4) found that, apart from a reduced anomalous viscosity, the hyaluronate-protein complexes of synovial fluid differed from normal and showed increases in both protein content and amounts of basic amino acids. 

Local treatment of rheumatoid arthritis with hydrocortisone usually results in restoration to normal of the qualitative hyaluronic acid changes occurring in joint fluids (J9, S23). The increase in viscosity and hyaluro-nate concentration of synovial fluid after treatment with hydrocortisone is believed to result either from the influence of the hormone on synthesis of hyaluronic acid, or, indirectly from its anti-inflammatory action (J9, S23). The molecular sizes of hyaluronate in rheumatoid fluids usually show a continuous but skewed distribution treatment with hydrocortisone was found to reduce the less polymerized fractions, which were marked in severe cases (Nl). 

There are many kinds of natural biodegradable polymers. They are classified into three types according to their chemical structures, i.e., polysaccharides, polypeptides/proteins and polynucleotides/nucleic acids. Among them, polysaccharides, such as cellulose, chitin/chitosan, hyaluronic acid and starch, and proteins, such as silk, wool, poly( y-glutamic acid), and poly(e-lysin), are well known and particularly important industrial polymeric materials. 

In disaccharides and polymeric carbohydrates, the ether-type radicals such as 7 and 8 have the radical site proximate to the glycosidic linkage and therefore play a major role in its scission (see below). In glucosamine [20] and N-acetylglucosamine [21] as well as in their related polymers chitin, chitosan and hyaluronic acid, one must further consider radicals of the type 9-11. Thus, one may expect that in addition to the behaviour shown by the prototypical carbohydrate radicals, reactions such as are observed with amino acids (c/. [22]) and peptides (c/. [23-25]), may also play a role. 

The mean degree of polymerization of hyaluronic acid in synovial fluid is below normal in the pathological condition (B18, B34,... 

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