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PubMed1989

Early diagnosis and monitoring of transplanted human malignant mesothelioma by serum hyaluronic acid.

Serum concentrations of unhydrolyzed hyaluronic acid (HA) in nude mice bearing human malignant mesothelioma xenografts were determined by size-exclusion chromatography. HA rose to 8-16 micrograms/mL (controls: less than 1 micrograms/mL) by the fourth to fifth day after tumor (epithelial) transplantation, 3 to 5 days before palpability. Decreases in HA during late tumor growth are probably attributed to tumor necrosis, based on the observation that HA was 2.5 times less in necrotic than in viable tumor tissues. This serum biomarker, recognizable before physical detectability of xenografted tumors, should have applicability to monitoring experimental chemotherapy in mice and to early diagnosis and monitoring of human malignant mesothelioma.

Animals↗

PubMed2002

Behavior of fibroblasts on a porous hyaluronic acid incorporated collagen matrix.

A hyaluronic acid (HA) incorporated porous collagen matrix was fabricated at -70 degrees C by lyophilization. The HA incorporated collagen matrix showed increased pore size in comparison with collagen matrix. Biodegradability and mechanical properties of matrices were controllable by varying the ultraviolet (UV) irradiation time for cross-linking collagen molecules. Addition of HA to collagen matrix did not effect ultimate tensile stress after UV irradiation. HA incorporated collagen matrices demonstrated a higher resistance against the collagenase degradation than collagen matrix. In an in vitro investigation of cellular behavior using dermal fibroblasts on the porous matrix, HA incorporated collagen matrix induced increased dermal fibroblast migration and proliferation in comparison with collagen matrix. These results suggest that the HA incorporated collagen porous matrix assumes to enhance dermal fibroblast adaptation and regenerative potential.

Collagen↗

PubMed1990

Extracellular depolymerization of hyaluronic acid in cultured human skin fibroblasts.

The chain length of [3H]hyaluronic acid synthesized by cultivating human skin fibroblasts in the presence of [3H]glucosamine was investigated. [3H]Hyaluronic acid obtained from the matrix fraction was excluded from a Sepharose CL-2B column irrespective of the incubation period, whereas that from the medium was depolymerized into a constant chain length (Mr = 40,000). The reducing and non-reducing terminals of the depolymerized hyaluronic acid were N-acetylglucosamine and glucuronic acid, respectively. Prolonged incubation produced no oligosaccharides as shown by examination of hyaluronidase digests, suggesting the presence of a novel endo-beta-N-acetylglucosaminidase in cultured human skin fibroblasts.

Cells, Cultured↗

PubMed1998

Changes of tissue fluid hyaluronan (hyaluronic acid) in peripheral lymphedema.

Hyaluronan (hyaluronic acid or HA) is an important component of the extracellular matrix which is synthesized in the tissue, transported in lymph and catabolized mainly in lymph nodes and the liver. In 39 patients with chronic peripheral lymphedema, the HA content in lymphedematous interstitial fluid was measured using radioimmunoassay. For comparison, the concentration of HA in serum and normal tissue fluid were also determined. These samples were also tested for protein concentration. The results showed that the HA concentration in interstitial fluid of a lymphedema limb was 22 x 10(3) +/- 10(3) (aspiration) and 30 x 10(3) +/- 4 x 10(3) (wick) ng/ml which were significantly higher than that in interstitial fluid, serum and lymph of normal limbs (control) and interstitial fluid of limbs with venous edema (p < 0.001). The protein concentration in these fluids did not show significant differences between lymphedema and those with normal limbs. The findings suggest that HA stagnates in the limb with impaired lymph drainage which may exert a deleterious effect on the interstitium.

Arm↗

PubMed1986

Characterization of hyaluronic acid on tissue sections with hyaluronectin.

An affinity immunological procedure for hyaluronic acid detection on tissue sections is described. This new, sensitive, and specific technique is based on the high affinity of hyaluronectin for hyaluronic acid, utilizing anti-hyaluronectin-hyaluronectin immune complexes. Elimination of binding when the reagent was supplemented with hyaluronic acid or when Streptomyces hyaluronidase-digested tissue sections were used emphasizes the specificity of the assay. This technique made possible accurate HA localization in embryonic mesenchyme, in neural tissue, in kidney medulla, and in tumors.

Antibodies↗

PubMed1989

Sera of children with renal tumours contain low-molecular-mass hyaluronic acid.

The molecular mass of hyaluronic acid (HA) rather than its serum concentration alone may be a hallmark of certain types of malignancy. A radiometric assay was used to measure HA levels in 35 children with renal tumours [33 Wilms' tumours and 2 bone metastasizing renal tumours of childhood (BMRTC)] and 20 normal siblings of children with cancer. The HA level in the sera of normal children was barely detectable and had a molecular mass of 1-5 x 10(5). In both Wilms' and BMRTC patients, very high levels of HA were found in preoperative serum samples; these fell dramatically following surgical excision of the tumours. A novel finding of our study was the presence of low-molecular-mass HA (similar to the angiogenic fragments of HA) in the sera of BMRTC patients. In contrast, high-molecular-mass HA (which is not angiogenic) was found in the sera of Wilms' patients (2 x 10(6) kDa). Following surgery in BMRTC patients, not only did serum HA levels fall to a value within normal ranges, but also the HA which remained was of high molecular mass.

Adolescent↗

PubMed1999

Hyaluronic acid by atomic force microscopy.

Hyaluronic acid (HA) of different molecular weights has been examined by atomic force microscopy (AFM) in air. This technique allows 3-D surface images of soft samples without any pretreatment, such as shadowing or staining. In the present study we examined the supermolecular organization of HA chains when deposited on mica and graphite, to better understand the interchain and intrachain interactions of HA molecules in solution. The concentration of the solution deposited varied from 0.001 to 1 mg/ml. On both substrates, and independent of the concentration, high-molecular-mass HA formed networks in which molecules ran parallel for hundreds of nanometers, giving rise to flat sheets and tubular structures that separate and rejoin into similar neighboring aggregates. Accurate measurements of the thickness of the thinnest sheets were consistent with a monolayer of HA molecules, 0.3 nm thick, strongly indicating lateral aggregation forces between chains as well as rather strong hydrophilic interactions between mica and HA. The results agree with an existing model of HA tertiary structure in solution in which the network is stabilized by both hydrophilic and hydrophobic interactions. Our images support this model and indicate that hydrophobic interactions between chains may exert a pivotal role in aqueous solution.

Aluminum Silicates↗

PubMed1993

Peritoneal lavage fluid protease levels after in vivo administration of tolmetin in hyaluronic acid.

Tolmetin sodium in a hyaluronic acid carrier (tolmetin-HA) was previously shown to reduce adhesion formation and alter the rate and extent to which wound repair cells enter the peritoneal cavity after surgery. In this study, the effect of tolmetin-HA on the levels of protease activities present in lavage fluid from the peritoneal cavity was determined at various postsurgical times. Collagenase activity in peritoneal lavage fluid was suppressed at 6, 12, and 24 hr after administration of tolmetin-HA in comparison to control. Elastase activity levels were biphasic with peak levels at 6 and 72 hr in lavage fluid from controls compared to peak levels at 6 and 48 hr in lavage fluid from treated rabbits. Plasminogen activator activity present in lavage fluid was significantly decreased at 48 hr after surgery in the tolmetin-HA-treated rabbits compared to controls. However, no alteration in the level of plasminogen activator inhibitor activity was observed in either the tolmetin-HA-treated or control rabbits. These data suggest that tolmetin-HA treatment altered the levels of neutral protease activity present in the peritoneal cavity and may therefore effect the proteolytic potential in the peritoneal cavity after surgery.

Animals↗

PubMed1995

Synthesis and release of hyaluronic acid by Swiss 3T3 fibroblasts.

Hyaluronic acid (HA) and its synthesis were studied in intact Swiss 3T3 mouse fibroblasts and isolated membranes. HA chains in culture medium, attached to cells and in isolated membranes, were determined to possess average M(r) values of 5.2 x 10(6), 1.8 x 10(6) and 0.14 x 10(6) respectively. Log cells were determined to possess 680,000 HA molecules/cell, and to release 120,000 HA chains/h. The time required for intact cells to synthesize and release a complete HA chain was approximately 4 h, with elongation proceeding at a rate of 57 dimers/min. The amount of cell-associated HA of various cell populations correlated strongly with their rate of HA release into culture media and with the HA synthetase activity determined for their membranes. Prevention of protein synthesis with cycloheximide decreased the rate of HA synthesis of log cells and HA synthetase activity of isolated membranes by 50% within 2-3 h. Because of the similarity between the biological lifetime of HA synthetase and the time required to synthesize a HA chain, we propose a model where each synthetase makes only one HA chain; after synthesis of a complete HA chain, HA synthetase activity is terminated as its HA chain is released from the cell.

3T3 Cells↗

PubMed1998

Production of prostanoids via increased cyclo-oxygenase-2 expression in human amnion cells in response to low molecular weight hyaluronic acid fragment.

Increased concentrations of hyaluronic acid (HA) have been found in serum and at uterine cervix at term. In its native form, HA exists as a high molecular weight (MW) polymer, but during parturition a lower MW HA fragment accumulates. The aim of this study was to investigate the regulatory mechanisms responsible for increased amnion prostanoid production and cyclo-oxygenase (COX) expression in response to HA. Human term amnion cells in culture were exposed to native HA polymer (MW 2.2x106) and its fragment (MW 3.5x104). We have determined levels of prostanoids, prostaglandins E2 and F2alpha, in conditioned media using specific immunoassays. Expression of COX-1 and COX-2 was examined with Western blot. Results were analyzed for statistical significance with Mann-Whitney U-test. Human amnion cells treated with HA fragment (100 nmol/l) produced significantly more PGE2 (2.3+/-0.21 (mean+/-S.D.) pg/106 cells/24 h) than controls (0.34+/-0.03) or high MW HA-treated cells (1.2+/-0.21). Protein levels of COX-2, but not COX-1, were substantially increased in amnion cells treated with HA fragment. HA fragment-mediated prostanoid production is markedly diminished by pretreatment with indomethacin. Our results indicate that HA fragment, rather than physiologic native HA polymer, induces amnion cell-derived prostanoid production via increased COX-2 expression. COX-2-mediated prostanoid production is likely a key physiologic event in HA fragment-mediated cervical ripening and the labor onset.

Amnion↗

PubMed1995

Hyaluronic acid metabolism in keloid fibroblasts.

Hyaluronic acid (HA), an important component of the tissue extracellular matrix, is a ubiquitous glycosaminoglycan (GAG) that forms a pericellular coat on the surface of cells. It has been speculated that this pericellular HA boundary may localize cytokines, such as transforming growth factor-beta 1, which is known to stimulate collagen production. The purpose of this study was to examine the role of HA and its cell surface receptor (CD44), an active participant in HA degradation, as they relate to keloid formation. Dermal excisions from both normal patients (n = 13) and keloid patients (n = 13) were analyzed for HA content using an alcian blue staining technique. Fibroblast cell cultures were used to quantitate HA synthesis and CD44 receptor density. Histological analyses showed a greater HA content in keloid tissue compared with normal dermal tissue. In agreement with this observation, keloid fibroblasts were found to synthesize significantly more HA than normal dermal fibroblasts (2469 +/- 483 cpm versus 1122 +/- 256 cpm, P = .02). Treatment of keloid fibroblasts with triamcinolone acetonide reduced the level of HA synthesis to that of normal fibroblasts (1560 +/- 477 cpm versus 1293 +/- 264 cpm, P = .6). However, there was no significant difference in HA receptor density on keloid cells compared with normal skin fibroblasts. Therefore, the increased HA deposits found in keloids are attributable to increased synthesis rather than to decreased degradation mediated by the CD44 receptor.

Adolescent↗

PubMed1996

Hyaluronan (hyaluronic acid) in human saliva.

Hyaluronan (hyaluronic acid) is a glycosaminoglycan that functions as a constituent of ground substance, a mediator of cell proliferation and would healing, and that plays a prominent part in tumorigenesis as well as in embryogenesis. Its presence and possible role in saliva has been subjected to little study. Unstimulated and stimulated pure parotid and mixed saliva was obtained from 10 volunteers. The protein content of the samples was assayed and the hyaluronan concentration was evaluated by means of an enzyme immunosorbent-like assay using a hyaluronan-binding peptide. Stimulated whole saliva had the highest protein content (mean 1.26 mg/ml) followed by unstimulated parotid saliva (1.15 mg/ml), stimulated parotid saliva (0.95 mg/ml) and unstimulated whole saliva (0.93 mg/ml). Absolute hyaluronan concentrations were highest in unstimulated whole saliva (mean 459.2 ng (nanograms)/ml), and lowest in stimulated parotid saliva (82.7 ng/ml). When hyaluronan concentrations are expressed as ng/mg of protein, the highest are in the unstimulated whole saliva (mean 477.5 ng/mg protein) followed by stimulated parotid saliva (229.7 ng/mg), unstimulated parotid saliva (179.6 ng/mg) and stimulated whole saliva (159.9 ng/mg). There are wide variations in the levels of hyaluronan in human saliva depending on the type of saliva and the conditions at the time of collection. Regulation of hyaluronan metabolism represents an intricate balance between production and degradation, and it is unclear whether elevated concentrations of hyaluronan in response to tissue proliferation, regeneration or repair. The hyaluronan may contribute to the healing properties of saliva, assisting in protecting the oral mucosa and adding to the lubricating properties of saliva.

Adult↗

PubMed2004

Cross talk between COX-2 inhibitor and hyaluronic acid in osteoarthritic chondrocytes.

Both hyaluronic acid (HA) and cyclooxygenase-2 (COX-2) inhibitors are used in clinical practice in the treatment of osteoarthritis. There have been no reports regarding cross-talk between HA and COX-2 inhibitors in articular human chondrocytes. The purpose of this study was to investigate whether HA, COX-2 inhibitors or a combination of COX-2 inhibitors and HA have different effects in human articular between lower and highly degenerated chondrocytes. Isolated lower and highly degenerated chondrocytes were divided into 5 groups: ethanol (used as a control for the solvents), HA, COX-2 inhibitors, COX-2 inhibitors plus HA, or no additive. After incubating for 48 h, mitochondrial membrane potential analysis and western blotting of p38 and p44/42 mitogen-activated protein kinase (MAPK) were performed. Glycosaminoglycan, nitric oxide (NO) production and prostaglandin E2 (PGE2) concentrations were assessed. A combination of COX-2 inhibitors and HA resulted in dendritic, proliferating chondrocytes with strong red fluorescence enriched in the mitochondrial membrane, and indicated reduction of apoptosis in chondrocytes. COX-2 inhibitors alone, and a combination of COX-2 inhibitor and HA inhibited the activation of p38 in highly degenerated chondrocytes. A combination of COX-2 inhibitors and HA decreased NO production in highly degenerated chondrocytes. COX-2 inhibitors decreased PGE2 production, however, HA alone had no effect on PGE2 production. The present study demonstrated that COX-2 inhibitors and HA interacted synergistically the MAPK pathway and inhibition of NO production in highly degenerated chondrocytes. Administration of COX-2 inhibitors plus HA could be used as a new alternative way of treating osteoarthritis.

Adjuvants, Immunologic↗

PubMed1988

Hyaluronic acid in human articular cartilage. Age-related changes in content and size.

Total tissue content and molecular mass of hyaluronic acid was determined in papain digests of human articular cartilage using a sensitive radiosorbent assay [Laurent & Tengblad (1980) Anal. Biochem. 109, 386-394]. 1) Hyaluronic acid content increased from 0.5 microgram/mg wet wt. to 2.5 micrograms/mg wet wt. between the ages of 2.5 years and 86 years. 2) Hyaluronic acid chain size decreased from Mr 2.0 x 10(6) to 3.0 x 10(5) over the same age range. 3) There was no age-related change in the size of newly-synthesized hyaluronic acid, which was of very high molecular mass, in both immature and mature cartilage. The results are consistent with an age-related decrease in proteoglycan aggregate size and suggest that modification of the hyaluronic acid chain may take place in the extracellular matrix.

Adolescent↗

PubMed2006

[Treatment of sensorineural hearing loss in acute viral otitis media with intratympanic dexamethasone and hyaluronic acid in comparison with intravenous therapy].

BACKGROUND: Intratympanic dexamethasone with hyaluronic acid has shown to be an effective treatment of the inner ear damage in sudden hearing loss and Menière's disease. It is not known yet if the same applies to the toxic inner ear damage in acute viral otitis media. PATIENTS: Retrospectively, 26 patients who suffered from acute viral otitis media with sensorineural hearing loss were examined with regard to the improvement of their inner ear hearing loss. Twelve patients were treated with intravenous therapy only, consisting of hydroxyethyl starch, pentoxifylline and prednisolone. Fourteen patients additionally received intratympanic injections, consisting of dexamethasone and hyaluronic acid once acute inflammatory changes subsided. The inner ear hearing loss was evaluated by means of standard bone-conduction audiometry. RESULTS: Neither local nor systemic side effects of the intratympanic injections occurred. During treatment no significant difference in the improvement of bone-conduction thresholds in any frequency was seen between the two groups. CONCLUSIONS: Intratympanic injections of dexamethasone with hyaluronic acid do not result in any additional benefit on the sensorineural hearing loss in acute viral otitis media compared to intravenous therapy alone. A reason might be the post inflammatory changes of the round window membrane or the toxic nature of the acute viral infection affecting the inner ear.

Acute Disease↗

PubMed2006

Influence of hyaluronic acid on the time-dependent friction response of articular cartilage under different conditions.

Therapeutic lubricant injections of hyaluronic acid are a relatively recent treatment for osteoarthritis. Their efficacy, however, in vivo has been subject to much debate. Frictional properties of cartilage-cartilage contacts under both static and dynamic loading conditions have been investigated, using healthy cartilage and cartilage with a physically disrupted surface, with and without the addition of a therapeutic lubricant, hyaluronic acid. Most of the cartilage friction models produced typical time-dependent loading curves, with a rise in static friction with loading time. For the dynamic loading conditions the rise in friction with loading time was dependent on the spatial (and time) variation in the load on the cartilage plate. For sliding distances of 4 mm or greater, when the cartilage plate was unloaded during sliding, the dynamic friction remained low whereas, with shorter sliding distances, the dynamic friction increased with increasing loading time. Static friction was higher than dynamic friction (under the same tribological conditions). The 'damaged' cartilage models produced higher friction than healthy cartilage under equivalent tribological conditions. It was shown that hyaluronic acid was an effective boundary lubricant for articular cartilage under static conditions with both healthy and damaged cartilage surfaces. Hyaluronic acid was less effective under dynamic conditions. However, these dynamic conditions had low friction values with the control lubricant because of the effectiveness of the intrinsic biphasic lubrication of the cartilage. It was only under the tribological conditions in which the cartilage friction was higher and rising with increasing loading time because of depletion of the intrinsic biphasic lubrication, that the role of hyaluronic acid as an effective therapeutic lubricant was demonstrated.

Animals↗

PubMed2002

Effect of hyaluronic acid on intraocular pressure in rats.

PURPOSE: To study the effect of acute or chronic intracameral injection of hyaluronic acid on intraocular pressure (IOP) in rats. METHODS: Acute or chronic injections of hyaluronic acid were performed unilaterally in the rat eye's anterior chamber, whereas the contralateral eye was injected with saline solution. IOP was assessed daily or weekly by a tonometer in conscious rats. IOP was also assessed in both experimental groups at several intervals during the light-dark cycle. RESULTS: A single injection of hyaluronic acid induced an increase of IOP that lasted for 8 days (P < 0.01), whereas its chronic administration during 9 weeks induced a significant and sustained increase in IOP, compared with the eye injected with vehicle (P < 0.01). This hyaluronic acid-induced hypertension was significantly decreased by the application of 1 drop of brimonidine (0.2%), latanoprost (0.005%), or timolol (0.5%). Significant daily variations of IOP were observed in both control and hyaluronic acid-injected eyes, peaking during the dark phase (P < 0.001, ANOVA). CONCLUSIONS: These results suggest that the intracameral administration of hyaluronic acid could be a model of ocular hypertension in rats.

Animals↗

PubMed1991

Density-dependent expression of hyaluronic acid binding to vascular cells in vitro.

Alterations in glycosaminoglycans and their receptors have been associated with changes in cell proliferation during development, wound healing, regeneration, and remodeling. We have previously found a differential effect of hyaluronic acid on the attachment of vascular cells in vitro; endothelial cell (EC) attachment was improved on hyaluronic acid-coated substrates, whereas that of smooth muscle cells (SMC) was reduced (Orlidge and D'Amore, 1986). To determine if hyaluronic acid binding sites are involved in these different substrate preferences, we have studied specific hyaluronic acid binding to cultured bovine aortic EC and SMC. Since very large numbers of cells are required for these binding assays (3 x 10(6)/data point), and since the level of hyaluronate binding to fixed and native SMC and EC was similar, fixed cells were used throughout this study. The effect of cell density on hyaluronic acid binding was investigated. No significant difference was observed between hyaluronic acid binding to sparse and high density SMC. On the other hand, a more than threefold elevation in specific hyaluronic acid binding was observed on low density EC when compared to binding on high density EC. Hyaluronic acid binding was found to be specific; excesses of heparan sulfate and chondroitin sulfate had no effect on the levels of specific binding. Finally, the effect of cell passage on SMC binding of hyaluronic acid was measured. Specific binding was measured from 1st to 12th passage cells and was found to increase with passage number so that by passage 12, hyaluronic acid binding was fourfold that of 1st passage cells. These data support the concept that SMC may become less differentiated upon continuous culture. Our results indicate quantitative changes in the level of hyaluronic acid binding to vascular cells as a function of their growth state. Further, these data correlate well with in vivo observations which suggest a role for hyaluronic acid in vascular development.

Animals↗