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PubMed1979

Biosynthesis of hyaluronic acid by Streptococcus.

Synthesis of hyaluronic acid was investigated in a cell-free system derived from a strain of Group A streptococci. Preparative procedures were improved so that an enzyme system 70 times more active than that previously reported was obtained. The hyaluronic acid synthesized could be separated into trichloroacetic acid-soluble and -insoluble fractions. On the basis of pulse-chase experiments, it was shown that the trichloroacetic acid-insoluble fraction is a precursor of the soluble fraction. The release of the trichloroacetic acid-insoluble hyaluronic acid is specifically blocked with p-chloromercuribenzoate, without inhibition of chain elongation. The addition of butanol to trichloroacetic acid resulted in solubilization of all of the hyaluronic acid. No detectable difference in molecular size was observed between the two hyaluronic acid fractions, both of which were estimated to be more than one million daltons in size. Testicular hyaluronidase digestion of either one of the two types of hyaluronic acid yielded no high molecular weight fragments, indicating that hyaluronic acid is not bound covalently to protein. However, following incubation of enzyme assay mixtures with UDP-[14C]GlcUA, even in the absence of UDP-GlcNAc, radioactive high molecular weight hyaluronic acid was obtained which suggests that the enzyme system elongates rather than initiates hyaluronic acid chains. Tunicamycin did not inhibit hyaluronic acid synthesis, indicating lack of participation of an intermediate of pyrophosphorylpolyisoprenol type. The results obtained are consistent with the hypothesis that chain elongation of hyaluronic acid proceeds by alternate addition of monosaccharides from UDP-sugars by a membrane-bound synthesizing system followed by release of completed hyaluronic acid chains.

Carbohydrates↗
PubMed2005

Angioedema acute hypersensitivity reaction to injectable hyaluronic acid.

BACKGROUND: Injectable hyaluronic acid was introduced to European markets in 1996 and has demonstrated a high safety profile. We describe the first reported case of angioedema-type hypersensitivity following injection of the upper lip with non-animal-stabilized hyaluronic acid (NASHA) gel. OBJECTIVE: To report a case and discuss a potential mechanism for and treatment of angioedema-type hypersensitivity following injection with NASHA gel into the upper lip. METHODS AND MATERIALS: Not applicable. RESULTS: Not applicable. CONCLUSION: Although injectable hyaluronic acid has a high safety profile, this reaction is dramatic. Treatments and potential mechanisms are discussed.

Adjuvants, Immunologic↗
PubMed1977

Molecular weight of hyaluronic acid from rabbit skin.

Hyaluronic acid was prepared from adult rabbit skin. Defatted skin powder suspended in 0.5 M NaCl was homogenized, and total glycosaminoglycans were precipitated from this 0.5 M NaCl extract with cetylpyridinium chloride, then redissolved successively with increasing concentrations of NaCl and finally 0.5 N NaOH. Hyaluronic acid, the major acid glycosaminoglycan in the 0.5 M NaCl extract, was purified and fractionated by DEAE-Sephadex chromatography. The molecular weights ranged from 1 X 10(4) to 7.2 X 10(4). Alternatively, hyaluronic acid was obtained from adult rabbit skin without mechanical powdering and homogenizing. Defatted skin pieces were suspended in water and heated at 100 degrees, then the extract was digested with pronase followed by DNase [EC 3.1.4.5]. Glycosaminoglycans were excluded in gel filtration with Sephadex G-75. Hyaluronic acid and dermatan sulfate, the two major glycosaminoglycans of this tissue, were separated by gel chromatography on Sepharose 4B. The molecular weight of this hyaluronic acid ranged from 1.6 X 10(5) to 1.3 X 10(6). Yields of hyaluronic acid by these two methods were similar. Hyaluronic acid was probably degraded by the mechanical treatments in the first method. Other factors affecting the viscosity of the tissue extract were examined.

Animals↗
PubMed1967

The equilibrium sedimentation of hyaluronic acid and of two synthetic polymers.

1. The method of equilibrium sedimentation has been investigated as an alternative to osmotic-pressure measurement for determining thermodynamic properties of polymer solutions at relatively high concentrations. 2. The simplifications that must be made in the theoretical treatment are discussed. 3. Measurements have been made on samples of polyethylene glycol, neutralized polymethacrylic acid and hyaluronic acid. With the first and third, values of the ;non-ideality coefficients' have been obtained that agree with those obtained from osmotic measurements on the same materials. 4. Evidence has been obtained of the presence in hyaluronic acid preparations of a fraction that has either a lower degree of thermodynamic non-ideality or a higher density increment than the bulk of the sample. This fraction is not protein.

Chemical Phenomena↗
PubMed1992

Analysis of the streptococcal hyaluronic acid synthase complex using the photoaffinity probe 5-azido-UDP-glucuronic acid.

The mucopolysaccharide, hyaluronic acid, is an important component of both mammals and pathogenic streptococci. This high molecular weight polymer is synthesized by a membrane-associated, multisubunit hyaluronate synthase which utilizes UDP-glucuronic acid and UDP-N-acetylglucosamine as substrates. Using the photoaffinity probe, [beta-32P]5-azido-UDP-glucuronic acid, three streptococcal membrane proteins (42, 33, and 27 kDa) specifically photoincorporated this probe. Labeling of these proteins was enhanced in the presence of UDP-N-acetylglucosamine, whereas UDP-galactose or UDP-glucose had no effect on incorporation. UDP-glucuronic acid inhibited the labeling of the three proteins in a dose-dependent manner. Detergent-solubilized membrane proteins from transposon-inactivated hyaluronic acid capsule mutants no longer incorporated the probe. This was also the case when membranes from stationary phase organisms were tested. Finally, glucuronic acid no longer was incorporated into high molecular weight hyaluronic acid with either the mutant or stationary phase preparations. Further biochemical analysis will be required to demonstrate the exact role each of the proteins play in hyaluronic acid biosynthesis.

Affinity Labels↗
PubMed1989

Elimination and subsequent metabolism of circulating hyaluronic acid in the fetus.

Hyaluronic acid differs from other glycosaminoglycans in its lack of covalently linked peptide, absence of sulphate groups, and the exceptional size of its single-chain polymers. These differences can be related to its distinct physical and functional properties, and may be pertinent to its greater abundance in early tissue development. In mature animals, the turnover of hyaluronic acid in tissues is reflected at least partly in the blood stream. The metabolism of circulating hyaluronic acid was therefore studied in fetal sheep after intravenous injection of [3H]acetylhyaluronic acid. Between 95% and 99% was removed within 6 min. Plasma radioactivity decayed by first-order kinetics, with a half-life between 0.8 and 1.25 min. The rate of elimination did not vary materially with hyaluronic acid fractions of widely disparate average Mr or with fetal age between 70 and 120 days. 3H2O was detected in plasma within 8-10 min. Labelled material found in urine from 10 min onward included polymers greater than or equal to 70,000 Mr, which indicates that urine may be a source of hyaluronic acid in amniotic fluid. Elimination from the plasma took place mainly in the liver, where labelled material was largely recovered in small metabolic residues as early as 28 min after injection. These were shown by high pressure liquid chromatography (h.p.l.c.) to include water, acetate, N-acetylglucosamine and a fraction tentatively identified as N-acetylglucosamine 1-phosphate. Tritium radioactivity was detected in hepatic lipids but not those of the spleen. Estimated plasma turnover was in the order of 10 micrograms/min per kg body weight. This is about 3-10 times that in adult animals and is consistent with an increased inflow of hyaluronic acid generated during the maturation of developing tissues.

Amniotic Fluid↗
PubMedDate not supplied

Acid mucopolysaccharide metabolism in leprosy. 1. Storage of hyaluronic acid and its possible significance in the pathogenesis of leprosy.

A histochemical analysis of 102 skin biopsies from a variety of leprosy types revealed the persistent presence of hyaluronic acid in lepra cells of lepromas. In contrast, the hyaluronic acid content of tuberculoid epithelioid cells showed a minimum amount of hyaluronic acid and hyaluronic acid tended to disappear from these granulomas as they aged. The macrophages of dimorphous leprosy occupied an intermediate position with respect to hyaluronic acid content and distribution, resembling the tuberculoid in BT cases and the lepromatous expression in BL cases. It is suggested that hyaluronic acid, in a manner similar to M. leprae and lipid, has a quantitatively varied distribution reflecting the immunopathologic spectrum of leprosy. This finding suggests that acid mucopolysaccharide may be significantly involved in that host/parasite interaction in leprosy.

Adolescent↗
PubMed1992

Hyaluronic acid--syneretic glycosaminoglycan.

Hyaluronic acid from different sources, umbilical cord, vitreous, rooster comb and streptococcus, all exhibit a unique hydration behavior. Each hyaluronic acid and each different salt form has a maximum non-freezable water content at a set concentration beyond which the bound (non-freezable) water decreases. This type of behavior indicates a syneretic process simply due to concentration alone.

Animals↗
PubMed2003

Augmentation of glans penis using injectable hyaluronic acid gel.

Recently, injectable hyaluronic acid gel has been widely used in soft-tissue augmentation. We performed this study to identify the feasibility of hyaluronic acid gel for the augmentation of the glans penis. In experiment I, 0.2 cm(3) of hyaluronic acid gel (HA) was injected into the dermis of the glans penis of 25 New Zealand white rabbits via a 30 G needle. At 3, 7, 14, 30, and 90 days after injection, histological changes of glans were studied, respectively. In experiment II, 0.5 cm(3) of HA was injected into the dermis of the glans penis of 14 Beagle dogs via a 27 G needle. At 6 months after injection, histological changes of the glans penis were also evaluated. At the time of autopsy, the lung, liver, and spleen were studied for systemic adverse reaction in each separate experiment. In experiment I, various sized cavities filled with amorphous basophilic materials were noted in the lamina propria and corpus spongiosum of the glans penis. All implants were positively stained on alcian blue. The intensity decreased in a time-dependent manner. Until 14 days, minimal inflammatory reactions were noted, but no signs of inflammation were identified at 90 days. With the gradual decrease of inflammation, fibrosis and deposition of collagen were noted. In experiment II, implants were well maintained at 6 months after injection in the lamina propria. Grade 1 of the inflammatory reaction was noted in one case. In both the experiments, all the specimens were free from any foreign body reaction and systemic adverse reactions. In conclusion, these results suggest that hyaluronic acid gel can be easily injected into the lamina propria of the glans penis and reside until 6 months. Injectable hyaluronic acid gel has a potential as a new bioimplant for the augmentation of the glans penis.

Animals↗
PubMed1983

Tissue structure and macromolecular diffusion in umbilical cord. Immobilization of endogenous hyaluronic acid.

Diffusion of endogenous hyaluronic acid and 125I-labelled albumin, monitored by desorption from umbilical cord (Wharton's jelly) slices, was studied in relation to tissue structure. Diffusion of hyaluronic acid was Fickian and some two orders of magnitude slower than that in free solution. After treatment of tissue with trypsin which removes proteoglycan(s) and degrades glycoprotein microfibrils, hyaluronic acid mobility through the collagen fibril network that remains is increased by an order of magnitude. These findings indicate that the mobility of hyaluronic acid in tissue is reduced both by the collagen network and by the presence of proteoglycan(s) and/or microfibrils. Estimates of the reduction in mobility due to physical entanglements with the fibrillar networks show that these play a major role. The mobility of hyaluronic acid found for intact tissue is sufficient for it to permeate the extracellular space within its metabolic turnover time. Labelled albumin diffusion is intact tissue, on the other hand, is reduced by only some 30% relative to free solution. This is consistent with the approximate 10% reduction found for the polysaccharide-free tissue (given by the excluded volume fraction) and the approximate 20% reduction expected for the polysaccharides in the interstitial fluid. Similar effects appear to be involved in the mobility of endogenous diffusible proteins in tissue.

Connective Tissue↗
PubMed1968

Fractionation of ahyaluronic acid preparation in a density gradient. Some properties of the hyaluronic acid.

1. Hyaluronic acid was isolated from ox synovial fluid by sedimentation equilibrium in a caesium chloride density gradient (Silpananta, Dunstone & Ogston, 1967). The product was almost free from chondroitin sulphate and from protein. 2. Its composition did not differ significantly from that of the carbohydrate part of the protein-containing material isolated by filtration. Its physicochemical properties and molecular configuration were similar, except for its viscosity, which showed markedly reduced concentration-dependence and shear-dependence. This suggests that the associated protein tends to form links between molecules of hyaluronic acid. 3. The accurate measurement of viscosity at very low velocity gradient, by use of the damping of oscillations in a Couette viscometer, is described. 4. A method is described for measuring, approximately, the thermodynamic non-ideality of a solute from the shape of its schlieren curve at sedimentation equilibrium in a density gradient. 5. A value for the partial specific volume of hyaluronic acid in dilute salt solution was calculated from its isopycnic density in a caesium chloride gradient.

Animals↗
PubMed2003

A prospective, randomized, parallel group study analyzing the effect of BTX-A (Botox) and nonanimal sourced hyaluronic acid (NASHA, Restylane) in combination compared with NASHA (Restylane) alone in severe glabellar rhytides in adult female subjects: treatment of severe glabellar rhytides with a hyaluronic acid derivative compared with the derivative and BTX-A.

BACKGROUND: Over the past 15 years, BTX-A has become the standard treatment for dynamic glabellar furrowing. Some individuals have resting glabellar rhytides that are sufficiently deep that they respond poorly to BTX-A alone. OBJECTIVE: To compare the efficacy of BTX-A combined with intradermal nonanimal stabilized hyaluronic acid (NASHA) with the efficacy of NASHA alone in females with moderate to severe glabellar rhytides. METHODS: This was a prospective randomized study of 38 subjects with moderate to severe glabellar rhytides. Half of the subjects were treated with BTX-A and NASHA and the other half with NASHA alone. Their response was assessed clinically and photographically. RESULTS: By comparison with the NASHA-alone group, the BTX-A plus NASHA group showed a better response both at rest and on maximum frown, and this response was maintained for longer. The median time for return to preinjection furrow status occurred at 18 weeks in the NASHA-alone group compared with 32 weeks for the BTX-A plus NASHA group.

Adult↗
PubMed1985

The effect of synovial fluid proteins in the degradation of hyaluronic acid induced by ascorbic acid.

The degradation of hyaluronic acid induced by ascorbic acid and the effect of synovial fluid proteins, such as ceruloplasmin, transferrin, and albumin, were investigated on the basis of the elution volume and the molecular weight of hyaluronic acid using high-performance gel permeation chromatography. Hyaluronic acid was degraded to less than one-third of the original molecular weight in the range of the physiological concentrations of ascorbic acid. Synovial fluid proteins protected against the ascorbate-dependent degradation of hyaluronic acid at their physiological concentrations. It is suggested that the inhibitory activity of ceruloplasmin mainly depends on the ferroxidase activity and that of transferrin is probably due to iron binding property.

Albumins↗