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Anomalous migration of hyaluronic acid oligomers in capillary electrophoresis: correlation to susceptibility to hyaluronidase.

During high-resolution capillary electrophoresis analysis in an electrolyte solution containing a neutral polymer, small oligomers of regularly arranged acidic polysaccharides such as hyaluronic acid and N-acetylneuraminic acid polymers showed reversal of the migration order. This anomalous migration was well correlated with their reported biological activity. In the present study, we analyzed hyaluronidase action on the purified hyaluronic acid oligomers using capillary electrophoresis and found that hydrolytic and transglycosylation actions by hyaluronidase were dependent on the molecular sizes of hyaluronic acid oligomers, and well correlated to their migration profiles. Furthermore, fluorescent polarization technique was employed for understanding the relationship between molecular size of hyaluronic acid oligomers and their electromigrations.

Animals↗

Hyaluronic acid enhances peripheral nerve regeneration in vivo.

Hyaluronic acid has been shown to enhance peripheral nerve regeneration in vitro. It has been proposed that, during the fibrin matrix phase of regeneration, hyaluronic acid organizes the extracellular matrix into a hydrated open lattice, thereby facilitating migration of the regenerating axons. Hyaluronic acid solutions and saline control solutions were injected into a nerve guide spanning a transected gap in the sciatic nerve of Sprague-Dawley rats (five in each group). Nerve conduction velocities were measured at 4 weeks by electromyography (EMG) before sacrifice of the animals. These studies demonstrated increased conduction velocities in the hyaluronic acid group compared with control animals (P = 0.006). After the animals were sacrificed, regenerated axon cables were quantified histologically, and axon branching was delineated by retrograde tracer analysis. In addition, the hyaluronic acid group showed an increase in myelinated axon counts at 4 weeks (P= 0.03). An increase in retrograde flow was demonstrated in the hyaluronic acid groups compared with animals receiving saline solution.

Animals↗

Hyaluronic acid in middle ear surgery.

The efficacy of hyaluronic acid when utilized in tympanoplasty was investigated in a multicenter, randomized, prospective patient blinded study. Of the 117 patients who completed the study, a majority (76) were treated with myringoplasty, 26 with myringoplasty combined with ossiculoplasty, and 15 with ossiculoplasty alone. The patients were evaluated by the operating surgeon up to 3 months following surgery, when the final assessment was made. The patients were divided into three groups: group 1 was treated with hyaluronic acid, 1 percent; group 2 with hyaluronic acid, 1.9 percent; and group 3 constituted the control where no hyaluronic acid was used at all. In the two test groups, utilizing hyaluronic acid, no gelatinous sponge was allowed to be left in the middle ear after surgery, whereas the control group was operated according to standard principles. The three groups were compared after the termination of the study as regards quality of healing and their hearing results. It could be concluded that the healing process within the middle ear and the tympanic membrane, as well as the hearing ability, was similar in all three groups. Thus no statistically significant differences could be obtained between the patient groups in which hyaluronic acid had been utilized in any concentration and the control group operated according to standard routine. This finding does not exclude, however, that hyaluronic acid might have a place in tympanoplastic surgery of today, since the long-term results were not evaluated here.

Adolescent↗

Increased urinary hyaluronic acid and interstitial cystitis.

PURPOSE: We compared urinary levels of hyaluronic acid in patients who met the National Institute for Diabetes, and Digestive and Kidney Diseases criteria for interstitial cystitis and in age matched healthy female controls. MATERIALS AND METHODS: Urinary hyaluronic acid was measured by solid phase radiometric assay using hyaluronic acid binding protein. Hyaluronic acid and symptom scores were compared in interstitial cystitis patients who gave multiple urine samples during treatment. Since hyaluronic acid changed with treatment in some patients, 17 samples from untreated interstitial cystitis patients were selected and compared with 17 control samples. RESULTS: Mean plus or minus standard deviation urinary hyaluronic acid concentrations were similar in the 2 groups (interstitial cystitis group 574 +/- 496, controls 512 +/- 324 ng./ml., p = 0.77). When normalized to creatinine urinary hyaluronic acid was significantly higher in interstitial cystitis patients (interstitial cystitis group 674 +/- 220, controls 446 +/- 220 ng./mg. creatinine, p = 0.0019). Urinary creatinine concentrations did not differ significantly (interstitial cystitis group 842 +/- 715, controls 1,162 +/- 516 mg./l., p = 0.12). CONCLUSIONS: Urinary hyaluronic acid was higher in interstitial cystitis patients than healthy controls. Since bladder hyaluronic acid is below the epithelium, this finding may indicate leakage across the epithelium into the urine in interstitial cystitis patients.

Adult↗

Intracochlear insertion of electrodes using hyaluronic acid in cochlear implant surgery.

Hyaluronic acid has been proposed as a lubricant for improving the outcome of cochlear implant surgery. We describe a method which includes coating the electrodes with a thin layer of hyaluronic acid as well as using a droplet of the lubricant on the cochleostomy to provide additional magnification, like a lens, that facilitates the insertion of the electrode array. The use of hyaluronic acid reduces trauma to the cochlea and avoids contaminating perilymph by blood or by saline used during the operation. It is an efficacious and reliable method for cochlear implant surgery.

Cochlear Implantation↗

Effects of adenosine 3':5'-cyclic monophosphate and serum on synthesis of hyaluronic acid in confluent rat fibroblasts.

A small amount of hyaluronic acid is synthesized in confluent cultures of rat fibroblasts, which have a high content of cyclic AMP. Addition of calf serum caused a rapid decrease in the cellular cyclic AMP content and large increases in hyaluronic acid synthetase activity and hyaluronic acid production. Addition of cyclic AMP also caused a marked increase in hyaluronic acid synthetase activity within 2h and then increased hyaluronic acid production. The effects of cyclic AMP and serum on hyaluronic acid synthesis were additive. Prostaglandin E2, which increased the cyclic AMP by stimulating adenylate cyclase, was as effective as cyclic AMP in increasing hyaluronic acid synthetase activity, but AMP was far less effective than cyclic AMP. These results indicate that cyclic AMP itself stimulates the mucopolysaccharide synthesis and that the effect of serum is not due to a decrease in cyclic AMP in the cells.

Animals↗

Streptococcal bacteriophage 12/12-borne hyaluronidase and its characterization as a lyase (EC 4.2.99.1) by means of streptococcal hyaluronic acid and purified bacteriophage suspensions.

Hyaluronic acid was obtained from filtrates of heat-killed cultures of Streptococcus pyogenes group A, strain K56, by simple ethanol precipitation and treatment with an adsorbent. The hyaluronic acid is pure as judged from chemical and sedimentation analyses. Particles of streptococcal bacteriophage 12/12 were isolated from phage-lysed group A streptococci by polyethylene glycol precipitation and isopyenic centrifugation. Electron micrographs of negatively stained preparations showed a typical Bradley group B virus with a long, flexible, cross-striated tail and a knob- or star-like structure at the distal tip of the tail. The hyaluronic acid is depolymerized upon incubation with the phage 12/12 virions. After extensive digestion, a mixture of at least four oligosaccharides is formed, the two smallest of which are a tetra- and octasaccharide terminating in reducing N-acetyl-D-glucosamine. The tetrasaccharide shows an absorption maximum at 231.5 nm with a molar extinction coefficient epsilon = 4820 litres X mole-1 X cm-1, and it is therefore concluded that the bacteriophage-borne hyaluronidase catalyses a beta-elimination. Accordingly it is classified as a hyaluronate lyase (EC 4.2.99.1).

Bacteriophages↗

Treatment of interstitial cystitis with Cystistat: a hyaluronic acid product.

OBJECTIVE: To determine whether intravesical hyaluronic acid id effective in reducing the urinary frequency and pain associated with interstitial cystitis/painful bladder syndrome (IC/PBS). MATERIAL AND METHODS: In a prospective, unblinded, uncontrolled pilot study, 20 patients (age range 34-80 years), all suffering from IC/PBS, received weekly bladder instillations of hyaluronic acid for 1 month and monthly instillations for a further 2 months. Patients were then offered further monthly instillations and all were subsequently evaluated after 3 years. Patient outcomes assessed were urinary frequency, use of analgesics and pain. RESULTS: All patients completed the 3 months of hyaluronic acid treatment with mean decreases in nocturia and pain of 40% and 30%, respectively, and decrease in analgesic use. Thirteen patients (65%) responded to treatment (responders) and continued therapy, while seven patents withdrew, six because of a lack of response and one due to cystectomy. In the 13 patients who continued hyaluronic acid instillations, four complete responders(30%) ceased therapy after a strong positive response (36%, 60% and 81% decreases compared to baseline in day-time voids, night-time voids and scores, respectively) which was maintained in the absence of continuous therapy, while after 3 years seven partial responders (35%) were still on therapy (25% and 43% decreases compared to baseline in day-time voids and pain scores, respectively). Two patients developed other diseases during follow-up and showed no response to long-term therapy. Hyaluronic acid was will tolerated by all patients. CONCLUSION: Hyaluronic acid safely reduced the pain and, to lesser degree, the urinary frequency associated with IC.

Adjuvants, Immunologic↗

Hyaluronic acid and type III procollagen peptide in jejunal perfusion fluid as markers of connective tissue turnover.

Hyaluronic acid (hyaluronate, HA) and type III procollagen N-terminal peptide were measured in jejunal perfusion fluid in an attempt to elucidate the turnover of connective tissue components in the small bowel in health and disease. In healthy controls (n = 16) the average concentration of hyaluronic acid in jejunal perfusion fluid was 12.2 +/- 2 micrograms/L (mean +/- SEM); the mean serum concentration was 22 +/- 7 micrograms/L. The type III procollagen N-terminal peptide concentration in jejunal fluid was 0.12 +/- 0.02 micrograms/L; the mean serum concentration was 12 +/- 0.7 micrograms/L. The albumin concentration in perfusion fluid was, on average, 0.04% of the serum values. Patients with celiac disease (n = 7) and Crohn's disease (n = 10) had normal serum levels of HA and type III procollagen N-terminal peptide. The jejunal secretion rate of HA was significantly increased in both disease groups and on average about three times higher than that in controls. The secretion rate of type III procollagen N-terminal peptide was not altered in celiac disease but increased more than three times in Crohn's disease. Habitual alcoholics investigated after alcohol withdrawal also had significantly increased jejunal secretion of HA but not of type III procollagen N-terminal peptide. In contrast, patients with alcoholic liver cirrhosis and similar ethanol intake had normal secretion of both substances. The findings of the study indicate that the secretion of HA into the jejunal lumen in health is considerable, possibly reflecting the rapid turnover of the intestinal mucosa. The enhanced jejunal secretion of HA in patients with celiac disease and Crohn's disease may be indicative of enhanced connective tissue response due to inflammation, but signs compatible with enhanced jejunal synthesis of type III collagen are only found in Crohn's disease. The HA secretion data in alcoholics might reflect (a) the active regeneration of the intestinal mucosa when ethanol is discontinued and (b) a possible role of the liver in this activity.

Adult↗

Safety data of injectable nonanimal stabilized hyaluronic acid gel for soft tissue augmentation.

BACKGROUND: Nonanimal hyaluronic acid gel was recently developed for soft tissue augmentation and volume expansion and has been shown to offer several advantages in comparison to other augmentation materials. There are rare reports of adverse events believed to be secondary to trace amounts of proteins in the hyaluronic acid raw material. OBJECTIVE: To determine the safety profile of nonanimal stabilized hyaluronic acid gel (Restylane, Perlane, Restylane Fine Lines, Q-Med AB, Uppsala, Sweden) for soft tissue augmentation using a retrospective review of all adverse events data from Europe, Canada, Australia, South American, and Asia from 1999 and 2000. RESULTS: Data from an estimated 144,000 patients treated in 1999 indicated the major reaction to injectable hyaluronic acid was localized hypersensitivity reactions, occurring in approximately 1 of every 1400 patients treated. In 1999 there was an adverse event reported for 1 of every 650 patients (0.15%) treated. These were temporary events that included redness, swelling, localized granulomatous reactions, bacterial infection, as well as acneiform and cystic lesions. For 2000 there was an estimated 262,000 patients treated with hyaluronic acid gel. The total number of adverse events was 144, corresponding to one adverse event for every 1800 patients (0.06%) treated. The major adverse event was again hypersensitivity, occurring in 1 of every 5000 patients treated. CONCLUSION: According to the reported worldwide adverse events data, hypersensitivity to nonanimal hyaluronic acid gel is the major adverse event and is most likely secondary to impurities of bacterial fermentation. According to data from 2000, the incidence of hypersensitivity appears to be declining after the introduction of a more purified hyaluronic acid raw material.

Gels↗

Inhibition of tumor metastasis in vivo by combination of paclitaxel and hyaluronic acid.

There is little information about the inhibitory effects of hyaluronic acid with paclitaxel on tumor metastasis and ascites formation. The aim of present study is to determine whether the combined administration of hyaluronic acid (HA) with paclitaxel can produce additional or synergistic therapeutic effects in the control of Lewis lung carcinoma (LLC) migration and ascites formation of U14 cervical tumor. The anti-metastasis effect of hyaluronic acid alone, paclitaxel alone and paclitaxel-hyaluronic acid combination were examined in a mouse model bearing LLC cells. i.v. Paclitaxel-hyaluronic acid, in the ratio of 1:3 (w/w), significantly reduced the migration of LLC cells in a synergistic fashion. In the experiment with mice bearing U14 tumor cells, i.p. paclitaxel-hyaluronic acid markedly improved the life span of mice and significantly decreased ascites formation when compared to paclitaxel alone or hyalunonan alone. We also analyzed the serum proteome of mice with lung neoplasm before and after treatment with paclitaxel-hyaluronic acid. Proteomic analysis on LLC mice was studied using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry. The results showed that i.v. administration of hyaluronic acid in combination with paclitaxel had significantly up-regulated the expression of vitamin D(3) binding proteins (DBP), which is a macrophage-stimulating activator. In conclusion, the in vivo anti-metastasis effect was associated with the synergistic therapeutic effects of hyaluronic acid-paclitaxel combination and a significant promotion of immune proteins expression. These results demonstrated that the combination of paclitaxel and hyaluronic acid may be an effective way to inhibit tumor migration.

Amino Acid Sequence↗

Hyaluronic acid metabolism in inflamed mesenterium of guinea pig.

Hyaluronic acid is known to play an important role in tissue remodeling and inflammatory process. To clarify the metabolism of hyaluronic acid in peritonitis, the biosynthesis of glycosaminoglycans in mesenterium was investigated in caseinate-induced peritonitis in guinea pig. Mesenterium showed acute inflammatory changes with polymorphonuclear leukocyte infiltration and produced much hyaluronic acid with a high molecular weight. Radioautography of inflamed tissue incubated with (3H)glucosamine demonstrated that radioactivity was incorporated predominantly by mesothelial cells and fibroblasts in the submesothelial cell layer. Intraperitoneal injection of human recombinant interleukin-1 alpha induced intraperitoneal accumulation of hyaluronic acid and its production by mesenterium. Heatlabile stimulating factor(s) for the biosynthesis of hyaluronic acid was present in the peritoneal fluid of inflamed guinea pigs. These results indicate that mesenterium is a hyaluronic acid-producing tissue and inflammatory changes of mesenterium are essential for the initiation and/or stimulation of hyaluronic acid production.

Animals↗

Reaction of unsaturated uronic acid residues with mercuric salts. Cleavage of the hyaluronic acid disaccharide 2-acetamido-2-deoxy-3-O-(beta-D-gluco-4-enepyranosyluronic acid)-D-glucose.

Degradation of connective-tissue polysaccharides with bacterial or fungal eliminases and subsequent characterization of the reaction products are now part of standard methodology for the analysis of these compounds. However, the scope of preparative and analytical work based on the use of eliminases has been limited by the lack of procedures for specific removal of the unsaturated uronic acid residues generated in the eliminase reactions. In the present investigation, we have shown that these residues are cleaved by mercuric salts under mild conditions that are not likely to affect other structures in an oligo- or poly-saccharide molecule. Thus the disaccharide generated from hyaluronic acid by digestion with chondroitinase AC or ABC was cleaved into a keto acid and free N-acetylglucosamine within 10 min at room temperature upon exposure to 14 mM-mercuric acetate at pH 5. The reaction of the disaccharide with mercuric salts was used for ready determination of the distribution of radioactivity between the glucuronic acid and N-acetylglucosamine moieties in radioactive hyaluronic acid that had been synthesized by IMR-90 fibroblasts from 3H-labelled monosaccharides. When the precursor was [3H]galactose, over 95% of the incorporated radioactivity was found in the glucuronic acid moiety. In contrast, cells grown in the presence of [3H]glucosamine synthesized a polysaccharide in which almost all of the label was located in the N-acetylglucosamine units. It is apparent from these experiments that the reaction of unsaturated uronic acid residues with mercuric salts provides a new tool with potential for many applications in the study of the structure and metabolism of connective-tissue polysaccharides.

Cell Line↗

Fate of exogenous hyaluronic acid in the middle ear.

The fate of exogenous high-molecular-weight hyaluronic acid applied in the middle ear was studied in rats. Tritium-labelled hyaluronic acid was deposited, and its disappearance through the eustachian tube was followed by analysis of nasopharyngeal secretions. Radioactivity in the secretions reached a peak after three hours and approached zero after 12 hours, indicating that almost all hyaluronic acid had been removed. The middle ears were all empty when opened 24 hours after the deposition of hyaluronic acid. The fate of hyaluronic acid after obstruction of the eustachian tube was followed both with radioactive hyaluronic acid and subsequent autoradiography and by direct analysis of the hyaluronic acid concentration and the hyaluronic acid molecular weight distribution. Radioactive hyaluronic acid was confined to the obstructed middle ear, and no uptake into surrounding tissues could be detected between three hours and four days after the deposition. The amount of hyaluronic acid deposited could be recovered to about the same extent for up to six days. Analysis of the molecular weight distribution of the deposited material indicated only a slow degradation, if any, during the same time period.

Animals↗

Influence of retinoic acid on the ultrastructure and hyaluronic acid synthesis of adult human epidermis in whole skin organ culture.

Normal human skin was maintained in organ culture under chemically defined conditions. All-trans retinoic acid was added to the culture medium at the final concentration of 5 mumol/l. After 5 days in culture samples were either harvested for electron microscopy or labeled with 3H-glucosamine for 24 h. After labeling, epidermis was separated from dermis and both tissue compartments were analyzed for the content of 3H-labeled glycosaminoglycans (GAGs) using CPC-precipitation and thin layer chromatography after enzymatic degradation into specific disaccharides. Retinoic acid caused a marked change in the epidermal tissue architecture. The epidermal cells were flattened and contained fewer desmosomes and tonofilaments than control explants. Retinoic acid induced accumulation of fine granular material in the intercellular spaces in the upper, and less dense, flocculent material in the lower epidermis. The analysis of 3H-glycosaminoglycans showed that in the epidermis retinoic acid elevated the amount of labeled hyaluronate by 70%, whereas sulfated GAGs were not significantly increased. In dermis the incorporation of 3H-glucosamine into neither hyaluronate nor sulfated GAGs was stimulated by the retinoic acid. It is concluded that retinoic acid significantly modifies the differentiation of normal adult human epidermis by decreasing cytoskeleton components and by inducing the synthesis of new intercellular material, at least a part of which is hyaluronic acid. As a consequence, the cohesion between the epidermal cells was apparently weakened.

Chromatography, Thin Layer↗

Photoimmobilization of sulfated hyaluronic acid for antithrombogenicity.

Anticoagulant polymer sulfated hyaluronic acid was patterned immobilized on a poly(ethylene terephthalate) (PET) film in a specific pattern by photolithography. Hyaluronic acid was sulfated by a sulfur trioxide-pyridine complex. The polymer was coupled with azidoaniline. The derivatized polymer was cast on a PET film from aqueous solution. After drying, the film was photoirradiated in the presence or absence of a photomask. The micropatterning was confirmed by staining with a dye, brilliant green. Since the anticoagulant polymer has negative charges, the cationic dye was adsorbed on the regions where the anticoagulant polymer was immobilized. Platelet adhesion was reduced on the sulfated hyaluronic acid-immobilized areas. The immobilized sulfated hyaluronic acid significantly reduced thrombus formation.

Blood Coagulation↗

Hyaluronic acid modulates proliferation of mouse dermal fibroblasts in culture.

When the concentration of hyaluronic acid was monitored in primary cultures of mouse skin dermal fibroblasts, there was an increase in hyaluronic acid proportional to the increase in cell number during the logarithmic growth phase. The concentration reached the maximum value 2 days before the cells became confluent, and then decreased gradually. Hyaluronic acid added at 1 mg ml-1 during the logarithmic phase either promoted or inhibited cell growth, depending on the density of cells at the time when hyaluronic acid was added. Hyaluronic acid (1 mg ml-1) added to subconfluent or postconfluent cultures induced a transient DNA synthesis with a consequent increase (greater than 20%) in cell number. The effects appeared to be specific, since neither hyaluronic acid oligosaccharides nor some other types of glycosaminoglycan (chondroitin, chondroitin sulphates, heparan sulphates and heparin) had any similar effects. Dibutyryl adenosine 3',5'-cyclic monophosphate (dbcAMP), at 1 mM, added to subconfluent or postconfluent cultures had promoting effects successively on hyaluronic acid synthesis and on cell growth. An increase in hyaluronic acid synthesis also occurred when dbcAMP was added to day 1 cultures in the logarithmic growth phase, but the effect on cell growth was reversed; there was an inhibition rather than a promotion. The pattern of cell density-dependent variation of the dbcAMP effect is quite similar to that observed with exogenously added hyaluronic acid. Therefore, we propose that hyaluronic acid added exogenously or supplied endogenously by increased synthesis may act as a modulator of mouse dermal fibroblast proliferation.

Animals↗

Insulin-like growth factor I (IGF-I) enhances hyaluronic acid synthesis in rabbit pericardium.

We examined which substances stimulate hyaluronic acid synthesis in rabbit pericardium and pericardial cells. (1) The addition of 10% (v/v) pericardial fluid to the incubation medium of the pericardium enhanced hyaluronic acid synthesis to about 2.5-times over the control, suggesting that there were some stimulating factors of the hyaluronic acid synthesis in the pericardial fluid. (2) The addition of 100 ng/ml insulin-like growth factor-I (IGF-I) to the incubation medium caused an approx. 2-fold increase of hyaluronic acid synthesis over the control in the pericardium. (3) IGF-I stimulated the hyaluronic acid synthesis in pericardial cells in a dose-dependent manner, but did not significantly stimulate the sulfated glycosaminoglycan synthesis. (4) The increase in the hyaluronic acid synthesis induced by IGF-I (100 ng/ml) or pericardial fluid was blocked by the copresence of monoclonal anti-IGF-I antibody. (5) IGF-I caused possible induction of the hyaluronic acid synthase activity and general protein and RNA synthesis before the initiation of DNA synthesis in pericardial cells. These results suggest a new biological action of IGF-I that stimulates hyaluronic acid synthesis in pericardium or the pericardial cavity of heart.

Animals↗