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PubMed1988

Hyaluronic acid synthesis and secretion by rat liver fat storing cells (perisinusoidal lipocytes) in culture.

The ability of rat liver fat storing cells to synthesize and to secrete hyaluronic acid was examined in monolayer cultures. The cells produce [3H] glucosamine-labeled hyaluronic acid, of which about 80% are secreted into the medium. The synthesis rate per cell (mg DNA) of labeled total glycosaminoglycans and hyaluronic acid in the medium increases significantly with culture time, but hyaluronic acid expressed as fraction of total glycosaminoglycans declines from about 0.70 in early cultures (up to the 4th day) down to 0.20 in advanced cultures. Cycloheximide increases and beta-D-xylopyranoside decreases significantly the fraction of hyaluronic acid in the medium, colchicine up to 5 microM was without effect. The synthesis of hyaluronic acid is a newly recognized function of this special type of sinusoidal liver cells. The results suggest that fat storing cells are likely to be a major source of hyaluronic acid in normal and probably also in injured liver.

Animals↗

PubMed1981

[Role of hyaluronic acid in the virulence of group A streptococci].

The effect of hyaluronic acid and hyaluronidase on the virulent properties of group A streptococci in mice were studied. The passage of streptococci belonging to different serotypes in mice was accompanied by a considerable increase of their virulence and the accumulation of hyaluronic acid. The electron microscopy of the initial and passaged strains allowed one to reveal the presence of considerable differences in their cell wall structure. The passaged strains had a pronounced filamentous and sharply thickened medium layer containing hyaluronic acid. The treatment of passaged streptococci of the infected mice with hyaluronidase did not induce decrease of virulence in the passaged cultures. The data obtained indicate that hyaluronic acid is not a virulence factor for mice. Such virulence may be determined by some component, not yet identified, of the filamentous layer of the cell wall in group A streptococci.

Animals↗

PubMed1998

Degradation of hyaluronic acid, poly- and monosaccharides, and model compounds by hypochlorite: evidence for radical intermediates and fragmentation.

Degradation of hyaluronic acid by oxidants such as HO. and HOCl/CIO- is believed to be important in the progression of rheumatoid arthritis. While reaction of hyaluronic acid with HO. has been investigated extensively, reaction with HOCl/ClO- is less well defined. Thus, little is known about the site(s) of HOCl/ClO- attack, the intermediates formed, or the mechanism(s) of polymer degradation. In this study reaction of HOCl/ClO- with amides, sugars, polysaccharides, and hyaluronic acid has been monitored by UV-visible (220-340 nm) and EPR spectroscopy. UV-visible experiments have shown that HOCl/ClO- reacts preferentially with N-acetyl groups. This reaction is believed to give rise to transient chloramide (R-NCl-C(O)-R') species, which decompose rapidly to give radicals via either homolysis (to produce N. and Cl.) or heterolysis (one-electron reduction, to give N. and Cl.) of the N--C bond. The nature of the radicals formed has been investigated by EPR spin trapping. Reaction of HOCl/ClO- with hyaluronic acid, chondroitin sulphates A and C, N-acetyl sugars, and amides gave novel, carbon-centered, spin adducts, the formation of which is consistent with selective initial attack at the N-acetyl group. Thus, reaction with hyaluronic acid and chondroitin sulphate A, appears to be localized at the N-acetylglucosamine sugar rings. These carbon-centered radicals are suggested to arise from rapid rearrangement of initial nitrogen-centered radicals, formed from the N-acetyl chloramide, by reactions analogous to those observed with alkoxyl radicals. The detection of increasing yields of low-molecular-weight radical adducts from hyaluronic acid and chondroitin sulphate A with increasing HOCl/ClO-concentrations suggests that formation of the initial nitrogen-centered species on the N-acetylglucosamine rings, and the carbon-centered radicals derived from them, brings about polymer fragmentation.

Acetamides↗

PubMed1987

Hyaluronic acid in bronchoalveolar lavage in rats exposed to quartz.

Hyaluronic acid, a connective tissue component, in bronchoalveolar lavage fluid (BAL) is correlated with decreased lung volumes in sarcoidosis. To investigate whether hyaluronic acid could be a marker of fibrosis in another interstitial lung disease, silicosis, the level of the substance in BAL fluid from rats exposed to crystalline silica (n = 3), amorphous silica (n = 3), and in one sham injected rat was measured. There was an increase in the total number of alveolar cells recovered in the rats exposed to crystalline silica and also a pronounced increase in the proportions of neutrophils and lymphocytes. In addition, the concentration of hyaluronic acid was high in this group of rats, and electron microscopic investigation of the lungs showed fibrosis. Thus hyaluronate in BAL fluid in rats exposed to crystalline silica seems to be a possible marker of fibrotic changes.

Animals↗

PubMed1991

Cooperative enhancement of hyaluronic acid synthesis by combined use of IGF-I and EGF, and inhibition by tyrosine kinase inhibitor genistein, in cultured mesothelial cells from rabbit pericardial cavity.

We examined the combined effects of IGF-I and EGF on hyaluronic acid synthesis using cultured pericardial mesothelial cells from rabbit pericardial cavity. Combined exposure of pericardial cells to IGF-I and EGF cooperatively increased hyaluronic acid synthesis and the level of hyaluronic acid synthase activity over that seen with or without IGF-I or EGF alone, but did not significantly stimulate the sulfated glycosaminoglycan synthesis. Increase in the level of hyaluronic acid synthesis and hyaluronic acid synthase activity induced by these growth factors was blocked after pretreatment with a tyrosine-specific protein kinase inhibitor, genistein. Genistein had no direct inhibitory effect on hyaluronic acid synthase activity. These results suggest that cooperative enhancement of hyaluronic acid synthesis induced by combined use of IGF-I and EGF could be mediated by a receptor tyrosine kinase-involved transmembrane signaling process that is responsive to IGF-I and EGF.

Animals↗

PubMed1988

Analysis by high-performance gel permeation chromatography of hyaluronic acid in animal skins and rabbit synovial fluid.

The simultaneous analysis of the molecular weight and concentration of hyaluronic acid in biological samples using high-performance liquid chromatography with two gel permeation columns is described. The elution volumes of various molecular weights of hyaluronic acids were linearily related to the logarithms of their molecular weights up to 600,000. The concentration of hyaluronic acid could be determined in the range from 20 to 100 micrograms/ml, i.e., from 4 to 20 micrograms per 200 microliter injected. The method was applied to the analysis of several animal skin extracts and rabbit synovial fluid. Skin extracts from mouse, rat, guinea-pig and rabbit could be chromatographed without prior isolation and purification. Hyaluronic acids in skin were separated clearly from chondroitin sulphates and their concentrations were determined. The molecular weights were estimated simultaneously to be more than 10(6). Rabbit synovial fluids from intact joints and saline- and carrageenin-treated joints could be chromatographed directly. The chromatograms showed that the concentration of hyaluronic acid in carrageenin-treated synovial fluid is lower than that in saline-treated fluid and the molecular weight distribution is broader. This technique enabled the rapid analysis of hyaluronic acid present at low levels in biological samples.

Animals↗

PubMed2001

Hyaluronic acid secretion during carbon dioxide pneumoperitoneum and its association with port-site metastasis in a murine model.

BACKGROUND: The mechanism of port-site metastasis after laparoscopic cancer surgery is unclear. This study aimed to determine whether carbon dioxide (CO2) pneumoperitoneum caused an increase in hyaluronic acid, which is secreted from mesothelial cells of the peritoneal cavity, and to assess the risk for port-site metastasis using a murine pneumoperitoneal model. METHODS: Sandwich-binding protein assay was used to measure the concentration of hyaluronic acid in the peritoneal cavity at 6, 12, 18, 24, 48, and 72 h after CO2 pneumoperitoneum or laparotomy for 30 min. The concentrations of hyaluronic acid during pneumoperitoneum were compared among different gases (CO2, helium, air), intervals (5, 30, 60 min), and pressures (0-2, 4-6, 8-10 mmHg). To investigate the effects of exogenous hyaluronic acid, the development of port-site metastasis was examined using mouse adenocarcinoma cell-line colon 26 cells. RESULTS: The intraperitoneal concentration of hyaluronic acid after CO2 pneumoperitoneum had increased already at 6 h, had reached the maximum level at 24 h, and had begun to decrease at 72 h. The concentration of hyaluronic acid at 24 h and 48 h in the CO2 pneumoperitoneum group was higher than that in the laparotomy group. This increase in hyaluronic acid also was found during helium and air pneumoperitoneum, and the concentration of hyaluronic acid in the peritoneal cavity was at its maximum when CO2 pneumoperitoneum lasted 30 min at 4 to 6 mmHg. The frequency of port-site metastasis was the highest when hyaluronic acid was injected during CO2 pneumoperitoneum (100%). CONCLUSIONS: In a murine model, the intraperitoneal concentration of hyaluronic acid was significantly increased after CO2 pneumoperitoneum, and the increase was more evident than that after laparotomy. Increased hyaluronic acid during pneumoperitoneum may be associated with port-site metastasis after laparoscopic cancer surgery.

Adenocarcinoma↗

PubMed1975

Induction of hyaluronic acid synthetase activity in rat fibroblasts by medium change of confluent cultures.

Hyaluronic acid synthesis in cultured cells usually occurs during the growth phase. The relation between hyaluronic acid synthetase activity and cell proliferation is studied. The synthetase activity in rat fibroblasts is high during the growth phase, but low in the stationary phase. When the old medium of stationary cultures is renewed with fresh medium containing 20% calf serum, DNA synthesis occurs synchronously between 12 and 20 hours, followed by cell division. Under these conditions, the hyaluronic acid synthetase activity is significantly induced within two hours, reaching a maximum level at 5--8 hours, and then decreases gradually. This induction of the synthetase, which shows a high turnover rate, requires continued synthesis of both RNA and protein. Furthermore, the induction of both DNA and hyaluronic acid synthesis is found to be caused by calf serum added in the medium. However, dialysis and ultrafiltration of the serum permit us to concentrate an active fraction with a high molecular weight, which induces the synthetase activity, but not DNA synthesis.

Blood↗

PubMed1977

Hormonal control of hyaluronic acid production in fibroblasts and its relation to nucleic acid and protein synthesis.

Whole serum and elevated pH previously had been found to stimulate both cell multiplication and hyaluronic acid production by chick embryo fibroblasts in culture. In a study to determine whether cell multiplication and hyaluronic acid production both respond to a single well-defined substance, insulin was found to stimulate, and cortisol to inhibit both processes coordinately. It appears, therefore, that multiplication and differentiated function in fibroblasts respond to a common underlying regulatory signal. Inhibition of ribosomal RNA synthesis by actinomycin D does not prevent serum stimulation of hyaluronic acid production, but inhibition of total RNA synthesis does. If total RNA synthesis is inhibited only after the hyaluronic acid production has reached a new high level, it continues at that level for the next five hours. The stimulatory treatment causes an increase in the activity of the enzyme hyaluronate synthetase. Inhibition of protein synthesis prevents any increase in hyaluronic acid production, and reduces the basal level of production. Reduction of the availability of Mg2+ in the medium coordinately inhibits DNA synthesis and hyaluronic acid production. The results are discussed in the light of a model for coordinate control growth and metabolism based on the availability of Mg2+.

Cell Division↗

PubMed1992

In vivo degradation of fetal wound hyaluronic acid results in increased fibroplasia, collagen deposition, and neovascularization.

Fetal tissue repair occurs without acute inflammation, prominent fibroplasia, or marked neovascularization. The fetal wound extracellular matrix is rich in hyaluronic acid (HA), while collagen is deposited in an organized normal dermal pattern. In various biologic systems, including regeneration and development, the controlled accumulation and subsequent degradation of hyaluronic acid is associated with distinct cellular and matrix events. Therefore, it is hypothesized that the abundance of hyaluronic acid in fetal wounds may influence cellular and/or matrix events such that tissue repair is highly organized and adult-like scarring does not occur. To test this hypothesis, the hyaluronic acid content of fetal rabbit wounds was reduced by specific degradation with Streptomyces hyaluronidase. Control wounds were treated with either enzyme buffer (n = 12) or denatured enzyme solution (n = 8) and exhibited a normal fetal healing response with scattered peripheral fibroblasts, a matrix of hyaluronic acid, and no infiltrating collagen. In marked contrast, the hyaluronidase-treated wounds (n = 14) demonstrated increased fibroblast infiltration, collagen deposition, and capillary formation. A significant reduction in the hyaluronic acid content of the hyaluronidase-treated wounds was confirmed biochemically. Since the degradation of hyaluronic acid resulted in an altered healing response, this study demonstrates that hyaluronic acid affects the cellular and matrix events in fetal healing and may be partially responsible for the unique qualities of this regenerative repair process.

Animals↗

PubMed2002

Hyaluronic acid's biomechanical stabilization function in the temporomandibular joint.

Hyaluronic acid is one of the components of synovial fluid. According to what is already well known in national and international biomedical literature, hyaluronic acid in the context of the TMJ serves two important biomechanical tasks. The first is feeding the articular cartilage; the second is lubricating the components of the joint. These two functions served by the same element change each other according to the continuous alternation of values of pressure in the articular cavity. The authors propose to overcome this statement by demonstrating that hyaluronic acid plays a third function in the TMJ, which is the biomechanical function of stabilizing the articular components.

Biomechanical Phenomena↗

PubMed1985

[The role of protein and hyaluronic acid in the synovial fluid in animal joint lubrication].

The purpose of this investigation was to study the role of protein and hyaluronic acid of synovial fluid in the animal joint lubrication. The D-fraction (0.2 micron up to 0.8 micron) from the bovine synovial fluid showed the lowest friction coefficient and contained about 20% protein and 70% hyaluronic acid of the synovial fluid. Protein but not hyaluronic acid of this fraction had lubricating ability, and the protein but not hyaluronic acid could support the lubricating film thickness. By electron microscopic observation hyaluronic acid was 2,000A-5,000A formless mass and the protein complex that had lubricating ability was 200A-300A spherical particle. Through these results I presume that hyaluronic acid enclose the spherical protein particles in its network like a cage of the roller-bearing and the particles can rotate freely like rolling elements of the roller-bearing. It was suggested that the roller-bearing mechanism was performed along with elastohydrodynamic lubrication in animal joint.

Animals↗

PubMed1993

Capsular hyaluronic acid in Pasteurella multocida type A and its counterpart in type D.

Hyaluronic acid was demonstrated in the capsule extract of 39/39 Pasteurella multocida type A strains by sodium chloride gradient chromatography followed by Alcian blue staining, and by a turbidometric method using acidified horse serum. Treatment with hyaluronidase from various sources eliminated these reactions. An Alcian blue staining substance of closely similar chromatographic properties occurred in capsule extracts of 14/16 type D strains but it resisted hyaluronidase and was thought to be an acidic polysaccharide differing from the hyaluronic acid of type A. Turbidometric values were lower than with type A strains, but were unaltered by hyaluronidase treatment. The type D substance could be precipitated from capsule extract by acriflavin. Both type A and D strains were mucoid and displayed large capsule zones in stained preparations. Photomicrographic measurements showed that hyaluronidase treatment of cell suspensions markedly reduced capsule dimensions of type A but not type D strains. When type A strains were cross streaked against a hyaluronidase + Staphylococcus aureus, their growth became non-mucoid at the intersection: mucoid type D strains were unaffected. Neither hyaluronic acid nor the hyaluronidase resistant type D substance could be detected in type B or E strains.

Bacterial Capsules↗

PubMed1980

The mechanism of estrogen-induced increase in hyaluronic acid biosynthesis, with special reference to estrogen receptor in the mouse skin.

The increase in hyaluronic acid and water contents induced by estradiol treatment in the mouse skin was dependent on dose and the number of treatments of estradiol. The anti-estrogen administered together with estradiol blocked the increase in hyaluronic acid content produced by treatment with estradiol alone. It was suggested that the anti-estrogen may act as an antagonist by competing for the cytoplasmic estrogen receptor on increase in hyaluronic acid synthesis. It was observed that the sensitivity in increase in hyaluronic acid biosynthesis by estradiol was related to the age of the mouse and the content of the cytoplasmic estrogen receptor in the mouse skin. It was suggested that there was a possible relationship between the increase in hyaluronic acid and cytoplasmic estrogen receptor in the mouse skin.

Animals↗

PubMed2005

[Studies on hyaluronic acid as dendifier in Shuanghuanglian eye-drops].

OBJECTIVE: To study the possibility of hyaluronic acid as densifier of Shuanguangliao eye-drops. METHOD: The factors related with hyaluronic acid s viscosity, such as pH-value and storing temperature, are tested in this experiment. At the same time, we checked the stimulation, stability of the densifier. RESULT: There was not effect on viscosity of pH-value and storing temperature. No stimulation on the eye was found after densified with hyaluronic acid. The viscosity properties of hyaluronic acid are stablile. CONCLUSION: The hyaliuronic acid added to Shuanghuanglian eye-drops are stabiliable and it can be applied in eye-drops. The increased viscosity is benefit to extend the residence time of drug in eye.

Animals↗

PubMed1982

The hydrodynamic resistance of hyaluronic acid and its contribution to tissue permeability.

An experimental system was developed to measure flow rates and pressure drops across hyaluronic acid solutions. The solutions were contained by membranes in a test cell, and solvent was perfused through the cell at flow rates comparable to physiological conditions. The pressure drop was found to be proportional to a steady flow rate for concentrations up to 1.5%, confirming that Darcy's Law for porous media is valid for hyaluronic acid solutions (and indicating that the polymer chains did not pile up at one end of the test cell). From the flow data, the hydrodynamic permeability of each solution was calculated and found to be 50 times higher that whole tissue having the same hyaluronic acid concentration; hyaluronic acid on its own, therefore, is not the source of resistance to flow in tissue. The results for hyaluronic acid were then used to show that all the glycosaminoglycans together cannot cause the high resistance of ground substance in tissue, and it is argued that mucoproteins are the most likely source. A hydrodynamic model of the polymer chains was developed to predict solution permeability; the theoretical values agree closely with the experimental data.

Biomechanical Phenomena↗

PubMed1977

Proteins retained with hyaluronic acid during ultrafiltration of synovial fluid.

The identity of the proteins associated with hyaluronic acid after ultrafiltration of bovine synovial fluid was examined. With discontinuous filtration, alpha2 macro- and IgM globulins were retained in hyaluronic complex both from synovial fluid and from a similar mixture of hyaluronic acid and serum. With continuous filtration and stirring to prevent formation of gels, protein was retained with hyaluronic acid in similar proportions. This protein showed immunologic identity with serum albumin, but differed in amino acid composition. After comparison with results of gel filtration, it was concluded that the identity of the retained proteins can be determined by the concentration of hyaluronic acid without variation in other ionic conditions.

Albumins↗

PubMed1980

Permeability of hyaluronic acid solutions. The effects of matrix concentration, calcium, and pH.

The permeability of hyaluronic acid solutions was measured in a chamber closed at each end of semi-permeable membranes. Permeability was strongly concentration dependent below 1.0 gm% hyaluronic acid. Small changes in the ionic environment of 1.0 gm% hyaluronic acid solutions also altered permeability. The permeability of such solutions decreased by a factor of 4.7 in the presence of as little as 5 mM calcium ion and showed optimum permeability at pH 7.0. The pH optimum was not noted in hyaluronic acid preparations known to contain only small amounts of protein.

Calcium↗