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PubMed1993

Human neutrophil chemokinesis and polarization induced by hyaluronic acid derivatives.

Neutrophils and macrophages are known to undergo significant modifications in their morphology and basal metabolism in response to chemical factors, in particular changes in the shape, movement, phagocytic activity and degranulation. These phenomena often involve an increase in chemokinesis and cellular secretory activity, usually expressed in antimicrobial activity. Once activated, the cells can move quickly towards the source of the stimulus, where they produce and release great amounts of enzymes (e.g. proteases, hydrolases, lysozyme) and reactive oxygen metabolites (e.g. O2-., H2O2, OH.). This study has examined the ability of surfaces of selected biomaterials to influence neutrophil morphology and locomotion. The surface of two films derived from hyaluronic acid derivatives were compared with that of glass. The two hyaluronic acid derivatives, despite having a similar chemical structure, were shown to interact with human neutrophils in different ways. A hyaluronic acid ethyl ester stimulated the whole population of neutrophils to take up a non-spherical morphology (polarize) and to move with a velocity similar to that of N-formyl-methionine-leucine-phenylalanine-stimulated cells on a glass surface. In contrast, only 44% of the examined cells on the surface of hyaluronic acid benzyl ester were polarized and their mean speed was only slightly higher with respect to that found with non-stimulated cells on glass. Moreover, while on the benzyl ester and on glass a correlation between neutrophil circularity (i.e. the shape of the cell) and cell speed was found, the ethyl ester did not show any correlation.

Biocompatible Materials↗

PubMed1994

Metabolism of hyaluronic acid by liver endothelial cells: effect of ischemia-reperfusion in the isolated perfused rat liver.

Liver endothelial cells appear to be particularly vulnerable to cold ischemia reperfusion. However, their function has not yet been evaluated, except using electron microscopic changes and trypan blue exclusion (an index of cell death). Hyaluronic acid is a polysaccharide highly extracted by normal liver endothelial cells. We thus evaluated liver endothelial cell function by measuring hyaluronic acid elimination in a model of ischemia-reperfusion injury using isolated perfused Wistar rat livers. We compared the effects of two preservation solutions during cold ischemia (4 degrees C): normal saline with 2 mM CaCl2 (4 h and 8 h ischemia) and the University of Wisconsin solution (8 h and 24 h ischemia). Eliminations were measured during two 40-min periods before and after ischemia; during each period, hyaluronic acid (150 ng/ml) and also, to evaluate hepatocyte function, propranolol (100 ng/ml) were infused into the reservoir. We show that, whatever the preservation solution or time used, liver endothelial cell function is altered to a larger extent than hepatocyte function. University of Wisconsin solution does not appear to protect liver endothelial cells during preservation, particularly after 24 h of cold ischemia. Hyaluronic acid elimination can be a useful tool in the investigation of an ideal preservation solution to protect liver endothelial cells from ischemia-reperfusion damage.

Adenosine↗

PubMed2004

Cumulus expansion, nuclear maturation and connexin 43, cyclooxygenase-2 and FSH receptor mRNA expression in equine cumulus-oocyte complexes cultured in vitro in the presence of FSH and precursors for hyaluronic acid synthesis.

The aim of this study was to investigate cumulus expansion, nuclear maturation and expression of connexin 43, cyclooxygenase-2 and FSH receptor transcripts in equine cumuli oophori during in vivo and in vitro maturation in the presence of equine FSH (eFSH) and precursors for hyaluronic acid synthesis. Equine cumulus-oocyte complexes (COC) were cultured in a control defined medium supplemented with eFSH (0 to 5 micrograms/ml), Fetal Calf Serum (FCS), precursors for hyaluronic acid synthesis or glutamine according to the experiments. After in vitro maturation, the cumulus expansion rate was increased with 1 microgram/ml eFSH, and was the highest with 20% FCS. It was not influenced by precursors for hyaluronic acid synthesis or glutamine. The expression of transcripts related to cumulus expansion was analyzed in equine cumulus cells before maturation, and after in vivo and in vitro maturation, by using reverse transcription-polymerase chain reaction (RT-PCR) with specific primers. Connexin 43, cyclooxygenase-2 (COX-2) and FSH receptor (FSHr) mRNA were detected in equine cumulus cells before and after maturation. Their level did not vary during in vivo or in vitro maturation and was influenced neither by FSH nor by precursors for hyaluronic acid synthesis. Results indicate that previously reported regulation of connexin 43 and COX-2 proteins during equine COC maturation may involve post-transcriptional mechanisms.

Animals↗

PubMed1967

Fractionation of a hyaluronic acid preparation in a density gradient. The isolation and identification of a chondroitin sulphate.

1. Following the suggestion of Nichol, Ogston & Preston (1967) that hyaluronic acid, prepared by filtration from ox synovial fluid, contains a component of high density, such material has been detected and isolated by equilibrium sedimentation in a density gradient of caesium chloride. 2. This material (fraction III) has been characterized as a chondroitin sulphate-protein complex of average molecular weight about 250000. Its amino acid pattern is characteristic of such complexes present in cartilage. It contains a proportion of glucosamine (as well as galactosamine); this is not due to contamination with hyaluronic acid. 3. Preliminary findings on fraction I (low density) and fraction II (intermediate density) suggest that these consist chiefly of protein and hyaluronic acid respectively.

Amino Acids↗

PubMed1991

Assay of synovial fluid hyaluronic acid using high-performance liquid chromatography of hyaluronidase digests.

A high-performance liquid chromatographic method for the determination of hyaluronic acid levels in synovial fluids has been developed. The hyaluronidase sample digests, containing an internal standard (benzoic acid), were separated on a reversed-phase octadecylsilyl column eluted with 0.01 M tetrabutylammonium phosphate-acetonitrile (83:17, v/v) at pH 7.35. The determination was made on 1:10 diluted samples, by using a calibration curve from 50 to 500 micrograms/ml of human umbilical cord hyaluronic acid. For validation, the synovial fluids were simultaneously analysed by this method and a radiometric method: a high correlation was found between the two (correlation coefficient 0.94). The proposed method can be used to determine specifically the high hyaluronic acid levels of synovial fluids without interferences from other glycosaminoglycans or non-steroidal anti-inflammatory drug treatment.

Adolescent↗

PubMed1994

Rapid detection of hyaluronic acid capsules on group A streptococci by buoyant density centrifugation.

One of the virulence factors of group A streptococci is the hyaluronic acid polysaccharide capsule. A rapid method for ascertaining the status of the capsule phenotype in Streptococcus pyogenes is described. Bacteria with a capsule have a lower buoyant density than acapsular or hyaluronidase-treated cells. Early log phase cultures were underlaid with 65% Percoll and centrifuged at 500-1000 g for 5 min. Upon visual examination, encapsulated cells were observed at the interface, whereas acapsular cells appeared in the pellet. Cultures that produced at least 7 micrograms/ml of hyaluronic acid per A600 unit of cells were detected at the interface; this level of polysaccharide is only about 0.5%-4% of that found for most mucoid strains. Therefore, this procedure can detect capsules around strains that do not appear to be encapsulated by light microscopy or do not possess mucoid colony morphology. Furthermore, this method reduces dependence on other expensive assays that use labile radioactive reagents to detect hyaluronic acid.

Centrifugation, Density Gradient↗

PubMed1986

The affinity of newly synthesized proteoglycan for hyaluronic acid can be enhanced by exposure to mild alkali.

The affinities for hyaluronic acid of newly synthesized proteoglycan from post-confluent rabbit chondrocyte cultures and purified bovine proteoglycan monomer were compared. In mixtures prepared at pH 6.8 the newly synthesized proteoglycan had the lower affinity; however, in mixtures incubated at pH 8.5 for 24 h before addition of hyaluronic acid, the newly synthesized proteoglycan exhibited a markedly higher affinity than the bovine monomer. The results suggest that proteoglycan secreted without associated link protein [Plaas, Sandy & Muir (1983) Biochem. J. 214, 855-864] has a low affinity for hyaluronate and that this may be increased during subsequent extracellular processing.

Alkalies↗

PubMed1992

Secretion of hyaluronic acid from synovial fibroblasts is enhanced by histamine: a newly observed metabolic effect of histamine.

We obtained evidence for the presence of histamine H1 and H2 receptors in normal synovial fibroblasts. Histamine enhanced proliferation of these synovial fibroblasts and stimulated the release of hyaluronic acid from these tissues. The molecular weight of hyaluronic acid decreased with this stimulation. The release of lower molecular weight hyaluronic acid from the synovium by histamine may be an important factor in joint disease.

Adolescent↗

PubMed1992

Chemiluminescence high-performance liquid chromatography for the determination of hyaluronic acid, chondroitin sulphate and dermatan sulphate.

A sensitive chemiluminescence high-performance liquid chromatographic method has been developed for the determination of hyaluronic acid, chondroitin sulphate and dermatan sulphate as their unsaturated disaccharide-dansylhydrazine derivatives involving an effective sample clean-up system. The dansylhydrazones of the unsaturated disaccharides derived from the hyaluronic acid, chondroitin sulphate and dermatan sulphate by chondroitinase ABC and/or chondroitinase ACII, were separated by reversed-phase chromatography using a mixture of 0.1 M sodium acetate buffer (pH 6.0) and 80% acetonitrile on a column (250 mm x 4.0 mm I.D.) packed with amide-80 silica beads (5 microns diameter). For post-column elution in the chemiluminescence system, 1 mM bis[2-(3,6,9-trioxadecanyloxycarbonyl)-4-nitrophenyl]oxalate and 3mM hydrogen peroxide in acetonitrile were used. The detection limit of each glycosaminoglycan was 100 fmol. The method was applicable to the determination of the levels of hyaluronic acid, chondroitin sulphate and dermatan sulphate in rat peritoneal mast cells.

Animals↗

PubMed2001

Rheologic changes in the synovial fluid of patients with gonarthritis induced by intraarticular infiltration of hyaluronic acid.

The aim of the present study was to evaluate possible changes in synovial fluid viscosity in gonarthritic patients treated with intraarticular infiltration of hyaluronic acid. Thirty patients with radiologically proven (Stage III Kellgren) serious gonarthrosis, local pain and functional limitation were enrolled. All patients had reported at least 4-5 episodes of hydrarthrosis during the previous 12 months. Therefore, two different phases of their illness could be observed: a relatively silent phase of hydrarthrosis and a symptomatic phase. According to the protocol, one sample of synovial fluid was collected for evaluation of baseline viscosity (pretreatment); immediately afterwards, intraarticular administration of high molecular weight sodium hyaluronate (one 20 mg vial/week for 3 weeks) was initiated. During the entire treatment period and for 3 weeks following the end of treatment, intraarticular synovial fluid samples (one sample per week for 3 treatment weeks followed by a further 3 weeks as control) were collected to perform rheologic assessment and viscosimetric analysis. The results of this preliminary study show that exogenous administration of high molecular weight sodium hyaluronate induced normalization of hyaluronic acid viscosity values in patients with high and low baseline hyaluronic acid viscosity values.

Aged↗

PubMed1991

Hyaluronic acid in a cardiac myxoma: a biochemical and histological analysis.

Cardiac myxoma is the most common primary tumor of the heart. This tumor has a gelatinous stroma that is thought to be composed of glycosaminoglycans, the classical acid mucopolysaccharide ground substance. We examined both biochemically and histologically the hyaluronic acid in a case of cardiac myxoma using a newly developed hyaluronic acid-binding protein probe. We observed that hyaluronic acid was localized in the amorphous stroma and occurred at levels 30 times that found in normal atrial septum.

Heart Neoplasms↗

PubMed2003

Photocrosslinked hyaluronic acid hydrogels: natural, biodegradable tissue engineering scaffolds.

Ideally, rationally designed tissue engineering scaffolds promote natural wound healing and regeneration. Therefore, we sought to synthesize a biomimetic hydrogel specifically designed to promote tissue repair and chose hyaluronic acid (HA; also called hyaluronan) as our initial material. Hyaluronic acid is a naturally occurring polymer associated with various cellular processes involved in wound healing, such as angiogenesis. Hyaluronic acid also presents unique advantages: it is easy to produce and modify, hydrophilic and nonadhesive, and naturally biodegradable. We prepared a range of glycidyl methacrylate-HA (GMHA) conjugates, which were subsequently photopolymerized to form crosslinked GMHA hydrogels. A range of hydrogel degradation rates was achieved as well as a corresponding, modest range of material properties (e.g., swelling, mesh size). Increased amounts of conjugated methacrylate groups corresponded with increased crosslink densities and decreased degradation rates and yet had an insignificant effect on human aortic endothelial cell cytocompatibility and proliferation. Rat subcutaneous implants of the GMHA hydrogels showed good biocompatibility, little inflammatory response, and similar levels of vascularization at the implant edge compared with those of fibrin positive controls. Therefore, these novel GMHA hydrogels are suitable for modification with adhesive peptide sequences (e.g., RGD) and use in a variety of wound-healing applications.

Absorbable Implants↗

PubMed1993

Age-dependent change in the hyaluronic acid content of the human chorioretinal complex.

OBJECTIVE: Hyaluronic acid (HA) has a key role in the structure and organization of the extracellular matrix. We sought to identify the distribution of HA in human eye tissue with regard to age using a biotinylated HA-binding protein. METHODS: Fetal and adult (from donors ranging from 28 to 94 years of age) eye tissues were fixed less than 24 hours post mortem and embedded in JB-4 medium (Polysciences, Warrington, Pa). Sections of 2-microns thickness were used. Control sections were pretreated either with Streptomyces hyaluronidase or HA-binding protein inactivated by HA. The binding of the protein to HA was detected with avidinbiotin alkaline phosphatase and developed by incubation with naphthol as-mx phosphate and Texas Red Salt (Pierce, Rockford, Ill). RESULTS: Specific staining for HA was observed in fetal eyes in the choroid, Bruch's membrane, sclera, retinal pigment epithelium, and developing retina from the vitreoretinal interface to the inner plexiform layer. Specific staining decreased with age in the choroid, retinal pigment epithelium, and Bruch's membrane. Hyaluronic acid-specific staining was undetectable in tissues from donors over 50 years of age. CONCLUSIONS: The localization of HA in the chorioretinal complex and its disappearance after the fifth decade of life may play a role in aging and age-related retinal disorders.

Adult↗

PubMed1986

Decreased collagen and hyaluronic acid content in lesional skin of acrogeria.

Biochemical analysis of involved and uninvolved skin of a 16-year-old female with acrogeria showed that hyaluronic acid and collagen contents were decreased only in involved skin. Explant cultures from both involved and uninvolved skin synthesized mainly hyaluronic acid in similar amounts. Since the glycosaminoglycans and hydroxyproline excreted in the urine were not increased, we speculate that a localized rather than a systemic abnormality may be present in acrogeria. Decreased collagen and hyaluronic acid contents in the patient are discussed in relation to Werner's syndrome and type IV Ehlers-Danlos syndrome.

Adolescent↗

PubMed1981

The effect of chondroitin-sulfate and hyaluronic acid on glycosaminoglycan and collagen synthesis and secretion by cultured arterial endothelial cells.

The effect of the addition of chondroitin-sulfate or hyaluronic acid to the culture medium on the glycosaminoglycan and collagen content and on the glycosaminoglycan composition of pig arterial endothelial cells and of the culture medium has been studied by biochemical and morphological methods. Both chondroitin-sulfate and hyaluronic acid were found to be transported to the interior of the cultured cells and then degraded. CSA, in addition enhanced collagen synthesis within the cells, but not the rate of excretion. Hyaluronic acid did not influence collagen formation.

Animals↗

PubMed1994

Local increase in hyaluronic acid and interleukin-2 in the capsules surrounding silicone breast implants.

Connective tissue disease-like illness has been associated with silicone breast implants. However, no data are currently available on the immunopathology of the capsule surrounding the breast implants. Sera from women with breast implants were collected and assayed for interleukin-6 (IL-6), IL-2, and hyaluronic acid. Capsular biopsies were stained with a probe for HYA or with monoclonal antibodies specific for human macrophages (CD68), T cells (CD4), IL-6, and IL-2. Control specimens consisted of breast biopsies from women undergoing reduction mammoplasty. Our results revealed an increased local amount of hyaluronic acid in the capsule of patients with breast implants compared with control breast tissue. The HYA was localized extracellularly in areas containing fibrosis and cellular infiltrates. The infiltrating cells were determined to be primarily macrophages and T cells. No IL-6 was localized in any of the tissue sections. In contrast, large amounts of IL-2 were found in regions of infiltrating lymphocytes. No significant increase in IL-6, IL-2, or hyaluronic acid was found in the sera. The role of hyaluronic acid and cytokines in the inflammatory response in the capsules of silicone breast implants is discussed.

Breast↗

PubMed2000

Hyaluronic acid as an anti-angiogenic shield in the preovulatory rat follicle.

Angiogenesis in the preovulatory follicle is confined to the theca cell layers, and penetration of capillaries through the basement membrane into the granulosa cell layers does not occur until after ovulation. However, elevated expression of the angiogenic growth factor (VEGF) has been reported in the cumulus cells surrounding the oocyte, which are expelled from the follicle during ovulation. This spatial and temporal discrepancy between VEGF expression and angiogenesis was studied here in the rat ovarian follicle, and we showed that cumulus cells secrete to the follicular fluid, in addition to VEGF, material with antiangiogenic activity that blocks endothelial cell proliferation, migration, and capillary formation in vitro. Hyaluronic acid produced by the cumulus cells can account for this antiangiogenic activity. Degradation of hyaluronic acid by hyaluronidase restored proliferation and migration of endothelial cells directed toward the cumulus. Inhibition of hyaluronic acid synthesis with 6-diazo-5-oxo-1-norleucine restored endothelial proliferation and migration in vitro, and it also resulted in early penetration of capillaries across the follicular basement membrane in vivo. These results support the role of hyaluronic acid produced by the cumulus cells as a high-molecular-weight, antiangiogenic shield that prevents premature vascularization of the preovulatory follicle by blocking endothelial cell migration and proliferation.

Animals↗

PubMed1985

Hyaluronic acid synthesis in articular cartilage: an inhibition by hydrogen peroxide.

The synthesis of hyaluronic acid by bovine articular cartilage in culture was inhibited after treatment with xanthine oxidase and hypoxanthine. Through the use of catalase, superoxide dismutase and the specific iron chelator diethylenetriaminepentaacetic acid, the active species responsible for inhibition was shown to be hydrogen peroxide. Hydrogen peroxide generated by glucose oxidase was also inhibitory. Some recovery of hyaluronic synthesis was evident after a further period of culturing. Proteoglycan synthesis was inhibited in parallel with hyaluronic acid synthesis.

Animals↗