Hyaluronan structure

Sobotka, L. Velebny, V. Ruzickova, J. Kusalova, M. Zadak, Z. In Hyaluronan Structure, Metabolism, Biological Activities, Therapeutic Applications Balazs, E.A. Hascall, V.C., Eds. Matrix Biology Institute Press Edgewater, NJ 2005, pp. 851-853. 

Cowman M.K., Matsuoka S. (2005) Experimental approaches to hyaluronan structure. Carbohydrate Research, 340,791-809. 

The studies by means of NMR and circular dichroism methods [29] made it possible to identify the presence of relatively rigid and more flexible structures alternating within a single hyaluronan chain with a balance between these structures. Extremely high viscosity of hyaluronan solutions was due, on the one hand to its structure and, on the other hand, was conditioned by specific and non-specific intermolecular interactions of macromolecules [29]. It all points to the fact that not only hydrophilic but also hydrophobic interactions play a significant role in stabilization of hyaluronan structure associated with the specific macromolecular structure. 

The problems of production and purification of hyaluronic acid are discussed in detail in Chapter 3. The comparable data of the commercial products are presented in Chapter 3 as well. The structure and rheological properties are discussed in Chapter 4. The discussion is united by a general idea about cooperative conformational transformations as the main phenomena that manifest bio-specificity of hyaluronic acid as well its unique effect of the relationships of biological properties from molecular mass. The physical and chemical methods of hyaluronan structural modification are presented in Chapter 5. It presents reactions of the macro-molecule cross-linking with bi-functional reagents as well as highly... 

Olczyk, P, et al., Hyaluronan Structure, metabolism, functions, and role in wound healing. Postepy Higieny I Medycyny Doswiadczalnej, 62 651-659,2008. 

The methylated derivatives served as the basis of elegant studies in which Jeanloz and his colleagues unequivocally established the structure of hyaluronan, dermatan sulfate, and the chondroitin sulfates. They also clarified many confusing issues, including the position of the sulfate groups in these polymers. In the course of this work, they proved that dermatan sulfate contained L-iduronic acid, a sugar not known before to occur in nature. 

Huntsman solvent-based collection and refining system, 15 506 Huron-Dow process, 14 42, 53 Huygens principle, 17 424 H values, 23 284 Hyaluronan, 20 577 Hyaluronic acid, 4 706 20 456 classification by structure, 4 723t function as ingredient in cosmetics, 7 829t... 

AJ Day. The structure and regulation of hyaluronan-binding proteins. Biochem Soc Trans 27 115-121, 1999. 

Kielty, C. M., Whittaker, S. P., Grant, M. E., and Shutdeworth, C. A. (1992). Type VI collagen microfibrils Evidence for a structural association with Hyaluronan. /. Cell Biol. 118, 979-990. 

Hyaluronan is present in the extracellular space and plays a structural role in cartilage and other tisanes. At nhvsinloaical concentrations the hvalumnan... 

Hyaluronan was identified by Karl Meyer11 in 1938 as a hexuronic acid-containing material that also provided the turgor for the vitreous of the eye. The name hyaluronic acid was proposed from the Greek hyalos (glassy, vitreous) and uronic acid. It required 20 years however before the chemical structure of HA was established.12 It was later found to be a present in virtually every vertebrate tissue, the highest concentrations occurring in the vitreous of the eye, in the synovial fluid in the joint capsule, and in the umbilical cord as Wharton s jelly. However, over 50% of total body HA is present in skin.13... 

Hyaluronan also occurs covalently bound to proteins such as inter-alpha trypsin inhibitor, a plasma protein that also functions as a stabilizer of HA-rich structures,21,22 such as the cumulus mass surrounding the mammalian ovum.23... 

Hyaluronan, despite the simplicity of its structure, has a surprisingly wide range of functions. In high concentrations, as found in the ECM of the dermis, it regulates water balance, osmotic pressure, functions as an ion exchange resin, and regulates ion flow. It functions as a sieve, to exclude certain molecules, to enhance the extracellular domain of cell surfaces, particularly the luminal surface of endothelial cells.28 It can also function as a lubricant and as a shock absorber. Hyaluronan can also act as a structural molecule, as in the vitreous of the eye, in joint fluid, and in Wharton s jelly. 

Scott, J.E., Secondary structures in hyaluronan solutions chemical and biological implications, in The Biology of Hyaluronan, Evered, D. and Whelan, J., Eds., John Wiley Sons, Chichester, 1989, p. 16. 

Scott, J.E. and Heatley, F., Biological properties of hyaluronan in aqueous solution are controlled and sequestered by reversible tertiary structures, defined by NMR spectroscopy, Biomacromolecules, 3, 547, 2002. 

Hyaluronan (HA) is a component of every tissue or tissue fluid in higher animals. The highest concentrations are found in cartilage, vitreous humor, and umbilical cord and even blood contains some HA. At physiologic pH, the molecule has been shown to adopt a helical structure and therefore the molecule can be modeled as a series of helical segments that are connected with flexible segments. However, based on results of solution studies, the molecular structure of HA appears to be more complicated. 

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